Detecting surface runoff location in a small catchment using distributed and simple observation method

NASA Astrophysics Data System (ADS)

Dehotin, Judicaël; Breil, Pascal; Braud, Isabelle; de Lavenne, Alban; Lagouy, Mickaël; Sarrazin, Benoît

2015-06-01

Surface runoff is one of the hydrological processes involved in floods, pollution transfer, soil erosion and mudslide. Many models allow the simulation and the mapping of surface runoff and erosion hazards. Field observations of this hydrological process are not common although they are crucial to evaluate surface runoff models and to investigate or assess different kinds of hazards linked to this process. In this study, a simple field monitoring network is implemented to assess the relevance of a surface runoff susceptibility mapping method. The network is based on spatially distributed observations (nine different locations in the catchment) of soil water content and rainfall events. These data are analyzed to determine if surface runoff occurs. Two surface runoff mechanisms are considered: surface runoff by saturation of the soil surface horizon and surface runoff by infiltration excess (also called hortonian runoff). The monitoring strategy includes continuous records of soil surface water content and rainfall with a 5 min time step. Soil infiltration capacity time series are calculated using field soil water content and in situ measurements of soil hydraulic conductivity. Comparison of soil infiltration capacity and rainfall intensity time series allows detecting the occurrence of surface runoff by infiltration-excess. Comparison of surface soil water content with saturated water content values allows detecting the occurrence of surface runoff by saturation of the soil surface horizon. Automatic records were complemented with direct field observations of surface runoff in the experimental catchment after each significant rainfall event. The presented observation method allows the identification of fast and short-lived surface runoff processes at a small spatial and temporal resolution in natural conditions. The results also highlight the relationship between surface runoff and factors usually integrated in surface runoff mapping such as topography, rainfall parameters, soil or land cover. This study opens interesting prospects for the use of spatially distributed measurement for surface runoff detection, spatially distributed hydrological models implementation and validation at a reasonable cost.

Atmospheric deposition and storm induced runoff of heavy metals from different impermeable urban surfaces.

PubMed

Wicke, Daniel; Cochrane, Thomas A; O'Sullivan, Aisling D

2012-01-01

Contaminants deposited on impermeable surfaces migrate to stormwater following rainfall events, but accurately quantifying their spatial and temporal yields useful for mitigation purposes is challenging. To overcome limitations in current sampling methods, a system was developed for rapid quantification of contaminant build-up and wash-off dynamics from different impervious surfaces. Thin boards constructed of concrete and two types of asphalt were deployed at different locations of a large carpark to capture spatially distributed contaminants from dry atmospheric deposition over specified periods of time. Following experimental exposure time, the boards were then placed under a rainfall simulator in the laboratory to generate contaminant runoff under controlled conditions. Single parameter effects including surface roughness and material composition, number of antecedent dry days, rain intensity, and water quality on contaminant build-up and wash-off yields could be investigated. The method was applied to quantify spatial differences in deposition rates of contaminants (TSS, zinc, copper and lead) at two locations varying in their distance to vehicle traffic. Results showed that boards exposed at an unused part of the carpark >50 m from vehicular traffic captured similar amounts of contaminants compared with boards that were exposed directly adjacent to the access route, indicating substantial atmospheric contaminant transport. Furthermore, differences in contaminant accumulation as a function of surface composition were observed. Runoff from asphalt boards yielded higher zinc loads compared with concrete surfaces, whereas runoff from concrete surfaces resulted in higher TSS concentrations attributed to its smoother surfaces. The application of this method enables relationships between individual contaminant behaviour and specific catchment characteristics to be investigated and provides a technique to derive site-specific build-up and wash-off functions required for modelling contaminant loads from impermeable surfaces.

The effect of the runoff size on the pesticide concentration in runoff water and in FOCUS streams simulated by PRZM and TOXSWA.

PubMed

Adriaanse, Paulien I; Van Leerdam, Robert C; Boesten, Jos J T I

2017-04-15

Within the European Union the exposure of aquatic organisms to pesticides is assessed by simulations with the so-called FOCUS Surface Water Scenarios. Runoff plays an important role in these scenarios. As little is known about the effect of runoff size on the exposure, we investigated the effect of runoff size on the concentration in the runoff water and in streams simulated with the PRZM and TOXSWA models for two FOCUS runoff scenarios. For weakly sorbing pesticides (K F,oc <100Lkg -1 ) the pesticide concentration in the runoff water decreased exponentially with increasing daily runoff size. The runoff size hardly affected the pesticide concentration in the runoff water of strongly sorbing pesticides (K F,oc ≥1000Lkg -1 ). For weakly sorbing pesticides the concentration in the FOCUS stream reached a maximum at runoff sizes of about 0.3 to 1mm. The concentration increased rapidly when the runoff size increased from 0 to 0.1mm and gradually decreased when runoff exceeded 1mm. For strongly sorbing pesticides the occurrence of the maximum concentration in the stream is clearly less pronounced and lies approximately between 1 and 20mm runoff. So, this work indicates that preventing small runoff events (e.g. by vegetated buffer strips) reduces exposure concentrations strongly for weakly sorbing pesticides. A simple metamodel was developed for the ratio between the concentrations in the stream and in the runoff water. This model predicted the ratios simulated by TOXSWA very well and it demonstrated that (in addition to runoff size and concentration in runoff) the size of the pesticide-free base flow and pesticide treatment ratio of the catchment determine the stream concentration to a large extent. Copyright © 2016 Elsevier B.V. All rights reserved.

Nutrient losses from manure and fertilizer applications as impacted by time to first runoff event.

PubMed

Smith, D R; Owens, P R; Leytem, A B; Warnemuende, E A

2007-05-01

Nutrient losses to surface waters following fertilization contribute to eutrophication. This study was conducted to compare the impacts of fertilization with inorganic fertilizer, swine (Sus scrofa domesticus) manure or poultry (Gallus domesticus) litter on runoff water quality, and how the duration between application and the first runoff event affects resulting water quality. Fertilizers were applied at 35 kg P ha-1, and the duration between application and the first runoff event varied between 1 and 29 days. Swine manure was the greatest risk to water quality 1 day after fertilization due to elevated phosphorus (8.4 mg P L-1) and ammonium (10.3 mg NH4-N L-1) concentrations; however, this risk decreased rapidly. Phosphorus concentrations were 2.6 mg L-1 29 days after fertilization with inorganic fertilizer. This research demonstrates that manures might be more environmentally sustainable than inorganic fertilizers, provided runoff events do not occur soon after application.

Use of a geomorphological transfer function to model design floods in small hillside catchments in semiarid Tunisia

NASA Astrophysics Data System (ADS)

Nasri, S.; Cudennec, C.; Albergel, J.; Berndtsson, R.

2004-02-01

In the beginning of the 1990s, the Tunisian Ministry of Agriculture launched an ambitious program for constructing small hillside reservoirs in the northern and central region of the country. At present, more than 720 reservoirs have been created. They consist of small compacted earth dams supplied with a horizontal overflow weir. Due to lack of hydrological data and the area's extreme floods, however, it is very difficult to design the overflow weirs. Also, catchments are very sensitive to erosion and the reservoirs are rapidly silted up. Consequently, prediction of flood volumes for important rainfall events becomes crucial. Few hydrological observations, however, exist for the catchment areas. For this purpose a geomorphological model methodology is presented to predict shape and volume of hydrographs for important floods. This model is built around a production function that defines the net storm rainfall (portion of rainfall during a storm which reaches a stream channel as direct runoff) from the total rainfall (observed rainfall in the catchment) and a transfer function based on the most complete possible definition of the surface drainage system. Observed rainfall during 5-min time steps was used in the model. The model runoff generation is based on surface drainage characteristics which can be easily extracted from maps. The model was applied to two representative experimental catchments in central Tunisia. The conceptual rainfall-runoff model based on surface topography and drainage network was seen to reproduce observed runoff satisfactory. The calibrated model was used to estimate runoff from 5, 10, 20, and 50 year rainfall return periods regarding runoff volume, maximum runoff, as well as the general shape of the runoff hydrograph. Practical conclusions to design hill reservoirs and to extrapolate results using this model methodology for ungauged small catchments in semiarid Tunisia are made.

A field study of colloid transport in surface and subsurface flows

NASA Astrophysics Data System (ADS)

Zhang, Wei; Tang, Xiang-Yu; Xian, Qing-Song; Weisbrod, Noam; Yang, Jae E.; Wang, Hong-Lan

2016-11-01

Colloids have been recognized to enhance the migration of strongly-sorbing contaminants. However, few field investigations have examined combined colloid transport via surface runoff and subsurface flows. In a headwater catchment of the upper Yangtze River, a 6 m (L) by 4 m (W) sloping (6°) farmland plot was built by cement walls to form no-flow side boundaries. The plot was monitored in the summer of 2014 for the release and transport of natural colloids via surface runoff and subsurface flows (i.e., the interflow from the soil-mudrock interface and fracture flow from the mudrock-sandstone interface) in response to rain events. The water sources of the subsurface flows were apportioned to individual rain events using a two end-member model (i.e., mobile pre-event soil water extracted by a suction-cup sampler vs. rainwater (event water)) based on δ18O measurements. For rain events with high preceding soil moisture, mobile pre-event soil water was the main contributor (generally >60%) to the fracture flow. The colloid concentration in the surface runoff was 1-2 orders of magnitude higher than that in the subsurface flows. The lowest colloid concentration was found in the subsurface interflow, which was probably the result of pore-scale colloid straining mechanisms. The rainfall intensity and its temporal variation govern the dynamics of the colloid concentrations in both surface runoff and subsurface flows. The duration of the antecedent dry period affected not only the relative contributions of the rainwater and the mobile pre-event soil water to the subsurface flows but also the peak colloid concentration, particularly in the fracture flow. The <10 μm fine colloid size fraction accounted for more than 80% of the total suspended particles in the surface runoff, while the colloid size distributions of both the interflow and the fracture flow shifted towards larger diameters. These results highlight the need to avoid the application of strongly-sorbing agrochemicals (e.g., pesticides, phosphorus fertilizers) immediately before rainfall following a long no-rain period because their transport in association with colloids may occur rapidly over long distances via both surface runoff and subsurface flows with rainfall.

A comparative study of the grain-size distribution of surface dust and stormwater runoff quality on typical urban roads and roofs in Beijing, China.

PubMed

Shen, Zhenyao; Liu, Jin; Aini, Guzhanuer; Gong, Yongwei

2016-02-01

The deposition of pollutants on impervious surfaces is a serious problem associated with rapid urbanization, which results in non-point-source pollution. Characterizing the build-up and wash-off processes of pollutants in urban catchments is essential for urban planners. In this paper, the spatial variation and particle-size distributions of five heavy metals and two nutrients in surface dust were analyzed, and the runoff water first-flush effect (FF30) and event-mean concentrations (EMCs) of 10 common constituents were characterized. The relationships between runoff variables and stormwater characteristics were examined from three typical urban impervious surfaces in Beijing, China. Dust on road surfaces with smaller grain sizes had higher pollutant concentrations, whereas concentrations of Mn, Zn, Fe, and TP in roof surface dust increased with grain size. Particles with grain sizes of 38-74 and 125-300 μm contributed most to the total pollutant load in roads, while particles with the smallest grain sizes (<38 μm) contributed most on roofs (23.46-41.71 %). Event-mean concentrations (EMCs) and FF30 values for most runoff pollutants tended to be higher on roofs than on roads. The maximum intensity (I max) and the antecedent dry days (ADD) were critical parameters for EMCs in roads, while ADD was the only dominant parameter for EMCs on our studied roof. The rainfall intensity (RI) and maximum intensity (I max) were found to be the parameters with the strongest correlation to the first-flush effect on both roads and roofs. Significant correlations of total suspended solids (TSS) concentration in runoff with grain-size fractions of surface dust indicated that coarser particles (74-300 μm) are most likely to contribute to the solid-phase pollutants, and finer particles (<38 μm) are likely the main source of dissolved pollutants.

[Characteristics of nutrient loss by runoff in sloping arable land of yellow-brown under different rainfall intensities].

PubMed

Chen, Ling; Liu, De-Fu; Song, Lin-Xu; Cui, Yu-Jie; Zhang, Gei

2013-06-01

In order to investigate the loss characteristics of N and P through surface flow and interflow under different rainfall intensities, a field experiment was conducted on the sloping arable land covered by typical yellow-brown soils inXiangxi River watershed by artificial rainfall. The results showed that the discharge of surface flow, total runoff and sediment increased with the increase of rain intensity, while the interflow was negatively correlated with rain intensity under the same total rainfall. TN, DN and DP were all flushed at the very beginning in surface flow underdifferent rainfall intensities; TP fluctuated and kept consistent in surface flow without obvious downtrend. While TN, DN and DP in interflow kept relatively stable in the whole runoff process, TP was high at the early stage, then rapidly decreased with time and kept steady finally. P was directly influenced by rainfall intensity, its concentration in the runoff increased with the increase of the rainfall intensity, the average concentration of N and P both exceeded the threshold of eutrophication of freshwater. The higher the amount of P loss was, the higher the rain intensity. The change of N loss was the opposite. The contribution rate of TN loss carried by surface flow increased from 36.5% to 57.6% with the increase of rainfall intensity, but surface flow was the primary form of P loss which contributed above 90.0%. Thus, it is crucial to control interflow in order to reduce N loss. In addition, measures should be taken to effectively manage soil erosion to mitigate P loss. The proportion of dissolved nitrogen in surface flow elevated with the decrease of rainfall intensity, but in interflow, dissolved form was predominant. P was exported mainly in the form of particulate under different rainfall intensities and runoff conditions.

Temporal variations in baseflow for the Little River Experimental Watershed in South Georgia

USDA-ARS?s Scientific Manuscript database

Hydrology is the driving force of sediment, nutrient, and pesticide movement. Separation of streamflow hydrographs into rapid surface runoff and baseflow can vastly improve our understanding of watershed processes. Data collected at the Little River Experimental Watershed (LREW) in the South Atlanti...

Rain, Snow, and Spring Runoff Revisited.

ERIC Educational Resources Information Center

Bohren, Craig F.

1995-01-01

Explores the theory behind the correlation between warm rain, rapid snowmelt, and the subsequent runoff using the concepts of enthalpy, thermal transfer, and energy transfer. Concludes that rapid runoff is not a consequence of rain per se but of the high humidities associated with the rain. (JRH)

Climatic Models Ensemble-based Mid-21st Century Runoff Projections: A Bayesian Framework

NASA Astrophysics Data System (ADS)

Achieng, K. O.; Zhu, J.

2017-12-01

There are a number of North American Regional Climate Change Assessment Program (NARCCAP) climatic models that have been used to project surface runoff in the mid-21st century. Statistical model selection techniques are often used to select the model that best fits data. However, model selection techniques often lead to different conclusions. In this study, ten models are averaged in Bayesian paradigm to project runoff. Bayesian Model Averaging (BMA) is used to project and identify effect of model uncertainty on future runoff projections. Baseflow separation - a two-digital filter which is also called Eckhardt filter - is used to separate USGS streamflow (total runoff) into two components: baseflow and surface runoff. We use this surface runoff as the a priori runoff when conducting BMA of runoff simulated from the ten RCM models. The primary objective of this study is to evaluate how well RCM multi-model ensembles simulate surface runoff, in a Bayesian framework. Specifically, we investigate and discuss the following questions: How well do ten RCM models ensemble jointly simulate surface runoff by averaging over all the models using BMA, given a priori surface runoff? What are the effects of model uncertainty on surface runoff simulation?

Remote sensing investigations at a hazardous-waste landfill

USGS Publications Warehouse

Stohr, C.; Su, W.-J.; DuMontelle, P.B.; Griffin, R.A.

1987-01-01

In 1976 state licensed landfilling of industrial chemicals was begun above an abandoned, underground coal mine in Illinois. Five years later organic chemical pollutants were discovered in a monitoring well, suggesting migration 100 to 1000 times faster than predicted by laboratory tests. Remote sensing contributed to the determination of the causes of faster-than-predicted pollutant migration at the hazardous-waste landfill. Aerial and satellite imagery were employed to supplement field studies of local surface and groundwater hydrology, and to chronicle site history. Drainage impediments and depressions in the trench covers collected runoff, allowing rapid recharge of surface waters to some burial trenches. These features can be more effectively identified by photointerpretation than by conventional field reconnaissance. A ground-based, post-sunset survey of the trench covers that showed that a distinction between depressions which hold moisture at the surface from freely-draining depressions which permit rapid recharge to the burial trenches could be made using thermal infrared imagery.In 1976 state licensed landfilling of industrial chemicals was begun above an abandoned, underground coal mine in Illinois. Five years later organic chemical pollutants were discovered in a monitoring well, suggesting migration 100 to 1000 times faster than predicted by laboratory tests. Remote sensing contributed to the determination of the causes of faster-than-predicted pollutant migration at the hazardous-waste landfill. Aerial and satellite imagery were employed to supplement field studies of local surface and groundwater hydrology, and to chronicle site history. Drainage impediments and depressions in the trench covers collected runoff, allowing rapid recharge of surface waters to some burial trenches.

Spatial multi-criteria analysis for selecting potential sites for aquifer recharge via harvesting and infiltration of surface runoff in north Jordan

NASA Astrophysics Data System (ADS)

Steinel, Anke; Schelkes, Klaus; Subah, Ali; Himmelsbach, Thomas

2016-11-01

In (semi-)arid regions, available water resources are scarce and groundwater resources are often overused. Therefore, the option to increase available water resources by managed aquifer recharge (MAR) via infiltration of captured surface runoff was investigated for two basins in northern Jordan. This study evaluated the general suitability of catchments to generate sufficient runoff and tried to identify promising sites to harvest and infiltrate the runoff into the aquifer for later recovery. Large sets of available data were used to create regional thematic maps, which were then combined to constraint maps using Boolean logic and to create suitability maps using weighted linear combination. This approach might serve as a blueprint which could be adapted and applied to similar regions. The evaluation showed that non-committed source water availability is the most restricting factor for successful water harvesting in regions with <200 mm/a rainfall. Experiences with existing structures showed that sediment loads of runoff are high. Therefore, the effectiveness of any existing MAR scheme will decrease rapidly to the point where it results in an overall negative impact due to increased evaporation if maintenance is not undertaken. It is recommended to improve system operation and maintenance, as well as monitoring, in order to achieve a better and constant effectiveness of the infiltration activities.

Surface runoff and tile drainage transport of phosphorus in the midwestern United States.

PubMed

Smith, Douglas R; King, Kevin W; Johnson, Laura; Francesconi, Wendy; Richards, Pete; Baker, Dave; Sharpley, Andrew N

2015-03-01

The midwestern United States offers some of the most productive agricultural soils in the world. Given the cool humid climate, much of the region would not be able to support agriculture without subsurface (tile) drainage because high water tables may damage crops and prevent machinery usage in fields at critical times. Although drainage is designed to remove excess soil water as quickly as possible, it can also rapidly transport agrochemicals, including phosphorus (P). This paper illustrates the potential importance of tile drainage for P transport throughout the midwestern United States. Surface runoff and tile drainage from fields in the St. Joseph River Watershed in northeastern Indiana have been monitored since 2008. Although the traditional concept of tile drainage has been that it slowly removes soil matrix flow, peak tile discharge occurred at the same time as peak surface runoff, which demonstrates a strong surface connection through macropore flow. On our research fields, 49% of soluble P and 48% of total P losses occurred via tile discharge. Edge-of-field soluble P and total P areal loads often exceeded watershed-scale areal loadings from the Maumee River, the primary source of nutrients to the western basin of Lake Erie, where algal blooms have been a pervasive problem for the last 10 yr. As farmers, researchers, and policymakers search for treatments to reduce P loading to surface waters, the present work demonstrates that treating only surface runoff may not be sufficient to reach the goal of 41% reduction in P loading for the Lake Erie Basin. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Runoff initiation from falling raindrops - comparison of smooth impervious surface and asphalt pavements. Effects of surface inclination and texture.

NASA Astrophysics Data System (ADS)

Nezlobin, David; Pariente, Sarah; Lavee, Hanoch; Sachs, Eyal; Levenberg, Eyal

2017-04-01

The processes of runoff initiation on smooth impervious surfaces and various asphalt pavements are investigated in laboratory rain simulator experiments and outdoor sprinkling tests. Visual and FLIR observations indicate that runoff initiation is associated with coalescence of drop clusters on the surface and complex changes in micro-connectivity. Depending on surface inclination, several morphological regimes of flow initiation have been observed. In the case of very small inclination the runoff initiation is governed by critical merging of drop clusters on the surface and develops in broad flows (very abrupt, but delayed). For larger inclinations, the runoff occurs in rivulets or strongly directed flow threads. On asphalt pavements the runoff initiation is also strongly affected by pavement SVF (Surface Void Fraction), texture and even by the asphalt hydrophobicity. A simplified bi-level model of the pavement surface may explain principal differences in the runoff initiation on asphalts with small, intermediate and large SVF values. For small SVF (standard fresh asphalts) the runoff develops on the upper surface level, and filling of the surface voids is not always required (especially for the large inclinations). For intermediate SVF (considerably deteriorated asphalts) the runoff develops as well on the upper surface level, but only after considerable filling of the surface voids. Finally, on severely deteriorated asphalts (very large SVFs) the runoff develops on the "bottom" level of asphalt surface, after only partial filling of the surface voids. Other factors, such as drops splash and splitting, also affect the process of runoff initiation and explain rather considerable differences (sometimes of 2-3 mm rain depth) in the runoff thresholds on various non-porous asphalt pavements. Similar phenomena can be probably observed on certain types of rock outcrops.

Microorganisms in stormwater; a summary of recent investigations

USGS Publications Warehouse

Mallard, Gail E.

1980-01-01

All storm runoff contains a variety of bacteria, including total coliform, fecal coliform, and fecal streptococci, which are derived from the land over which the water flows. Most total coliform are native soil organisms, whereas the fecal coliform and fecal streptococci originate from the feces of wild and domestic animals. Urban runoff has been reported to contain pathogenic organisms, but this probably presents little direct threat to human health because the runoff is not ingested. Runoff water can, however, have other negative effects such as contamination of surface water, which may result in beach closures, or contamination of shellfish. This type of contamination is generally of short duration because indicator bacteria and pathogens die out rapidly in the aquatic environment. Similarly, bacteria and viruses deposited on soil by stormwater are inactivated by drying, competition from soil microflora, and a variety of other processes. Every storm producing runoff is unique in the number and type of microorganisms because these vary from site to site, from storm to storm, and during the course of the storm. Stormwater to be examined for microorganisms must be collected in sterile containers and processed immediately. (USGS)

Using Automatic Control Approach In Detention Storages For Storm Water Management In An Urban Watershed

NASA Astrophysics Data System (ADS)

Goyal, A.; Yadav, H.; Tyagi, H.; Gosain, A. K.; Khosa, R.

2017-12-01

Increased imperviousness due to rapid urbanization have changed the urban hydrological cycle. As watersheds are urbanized, infiltration and groundwater recharge have decreased, surface runoff hydrograph shows higher peak indicating large volumes of surface runoff in lesser time durations. The ultimate panacea is to reduce the peak of hydrograph or increase the retention time of surface flow. SWMM is widely used hydrologic and hydraulic software which helps to simulate the urban storm water management with the provision to apply different techniques to prevent flooding. A model was setup to simulate the surface runoff and channel flow in a small urban catchment. It provides the temporal and spatial information of flooding in a catchment. Incorporating the detention storages in the drainage network helps achieve reduced flooding. Detention storages provided with predefined algorithms were for controlling the pluvial flooding in urban watersheds. The algorithm based on control theory, automated the functioning of detention storages ensuring that the storages become active on occurrence of flood in the storm water drains and shuts down when flooding is over. Detention storages can be implemented either at source or at several downstream control points. The proposed piece of work helps to mitigate the wastage of rainfall water, achieve desirable groundwater and attain a controlled urban storm water management system.

Stormwater Infrastructure at Risk: Predicting the Impacts of Increased Imperviousness due to Infill Development in a Semi-arid Urban Neighborhood

NASA Astrophysics Data System (ADS)

Hogue, T. S.; Panos, C.; McCray, J. E.; Gilliom, R.

2017-12-01

This research investigates the impacts of infill development (or "redevelopment") on urban stormwater runoff and explores avenues for re-inventing stormwater management strategies for the City of Denver, Colorado. As a rapidly developing city, Denver is facing a cycle of increasing population and redevelopment in the form of infill (where under-utilized parcels within the City are redeveloped into high-density residential land uses). Infill development increases stormwater runoff by introducing more impervious surfaces, including roofs and driveways, which produce more runoff (additional stormwater). However, there is debate on the impact of infill patterns on runoff behavior, peak flows, and flood frequency events. We used a calibrated, high-resolution PCSWMM model to simulate three redevelopment scenarios within the 1000-acre Berkeley neighborhood of northwest Denver. The scenarios utilized future predictions of redevelopment to simulate increases in imperviousness by 1.1, 4.5, and 8.7 percent by 2024, 2034, and 2044, respectively, for a range of design storms. Results predict that, on average, for each 1% increase in impervious area due to infill development, surface runoff volume will increase by 1.28% in the Berkeley neighborhood. Results demonstrate the limitations of the existing storm sewer network as pipes throughout the catchment reach capacity for events larger than the 2-yr storm for all three scenarios. Spatial maps of the catchment pinpoint subcatchments and sewer nodes of concern, namely surrounding a rapidly growing business corridor and the local Interstate. Overall, results indicate the infrastructure of the Berkeley neighborhood may be at risk, and that current stormwater capture policies may need to be revisited to accommodate both future infill development and climate change. This research provides a quantitative basis for implementing potential changes as well as examining the possibility of using the additional stormwater from redevelopment for beneficial use within Denver.

Geologic framework and hydrogeologic characteristics of the Edwards Aquifer outcrop, Comal County, Texas

USGS Publications Warehouse

Small, T.A.; Hanson, J.A.

1994-01-01

In Comal County, the Edwards aquifer is probably most vulnerable to surface contamination in the rapidly urbanizing areas on the Edwards aquifer outcrop. Possible contamination can result from spills, leakage of hazardous materials, or runoff onto the intensely faulted and fractured, karstic limestone outcrops characteristic of the recharge zone.

Variability of Snow Ablation: Consequences for Runoff Generation at the Process Scale and Lessons for Large Cold Regions Catchments

NASA Astrophysics Data System (ADS)

Pomeroy, J. W.; Carey, S. K.; Granger, R. J.; Hedstrom, N. R.; Janowicz, R.; Pietroniro, A.; Quinton, W. L.

2002-12-01

The supply of water to large northern catchments such as the Mackenzie and Yukon Rivers is dominated by snowmelt runoff from first order mountain catchments. In order to understand the timing, peak and duration of the snowmelt freshet at larger scale it is important to appreciate the spatial and temporal variability of snowmelt and runoff processes at the source. For this reason a comprehensive hydrology study of a Yukon River headwaters catchment, Wolf Creek Research Basin, near Whitehorse, has focussed on the spatial variability of snow ablation and snowmelt runoff generation and the consequences for the water balance in a mountain tundra zone. In northern mountain tundra, surface energetics vary with receipt of solar radiation, shrub vegetation cover and initial snow accumulation. Therefore the timing of snowmelt is controlled by aspect, in that south facing slopes become snow-free 4-5 weeks before the north facing. Runoff generation differs widely between the slopes; there is normally no spring runoff generated from the south facing slope as all meltwater evaporates or infiltrates. On the north facing slope, snowmelt provides substantial runoff to hillside macropores which rapidly route water to the stream channel. Macropore distribution is associated with organic terrain and discontinuous permafrost, which in turn result from the summer surface energetics. Therefore the influence of small-scale snow redistribution and energetics as controlled by topography must be accounted for when calculating contributing areas to larger scale catchments, and estimating the effectiveness of snowfall in generating streamflow. This concept is quite distinct from the drainage controlled contributing area that has been found useful in temperate-zone hydrology.

Suitability of a Saccharomyces cerevisiae-based assay to assess the toxicity of pyrimethanil sprayed soils via surface runoff: comparison with standard aquatic and soil toxicity assays.

PubMed

Gil, Fátima N; Moreira-Santos, Matilde; Chelinho, Sónia; Pereira, Carla; Feliciano, Joana R; Leitão, Jorge H; Sousa, José P; Ribeiro, Rui; Viegas, Cristina A

2015-02-01

The present study is aimed at evaluating whether a gene expression assay with the microbial eukaryotic model Saccharomyces cerevisiae could be used as a suitable warning tool for the rapid preliminary screening of potential toxic effects on organisms due to scenarios of soil and water contamination with pyrimethanil. The assay consisted of measuring changes in the expression of the selected pyrimethanil-responsive genes ARG3 and ARG5,6 in a standardized yeast population. Evaluation was held by assessing the toxicity of surface runoff, a major route of pesticide exposure in aquatic systems due to non-point-source pollution, which was simulated with a pyrimethanil formulation at a semifield scale mimicking worst-case scenarios of soil contamination (e.g. accident or improper disposal). Yeast cells 2-h exposure to the runoff samples led to a significant 2-fold increase in the expression of both indicator genes. These results were compared with those from assays with organisms relevant for the aquatic and soil compartments, namely the nematode Caenorhabditis elegans (reproduction), the freshwater cladoceran Daphnia magna (survival and reproduction), the benthic midge Chironomus riparius (growth), and the soil invertebrates Folsomia candida and Enchytraeus crypticus (survival and reproduction). Under the experimental conditions used to simulate accidental discharges into soil, runoff waters were highly toxic to the standard test organisms, except for C. elegans. Overall, results point out the usefulness of the yeast assay to provide a rapid preview of the toxicity level in preliminary screenings of environmental samples in situations of inadvertent high pesticide contamination. Advantages and limitations of this novel method are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

Modeling the Hydrologic Effects of Large-Scale Green Infrastructure Projects with GIS

NASA Astrophysics Data System (ADS)

Bado, R. A.; Fekete, B. M.; Khanbilvardi, R.

2015-12-01

Impervious surfaces in urban areas generate excess runoff, which in turn causes flooding, combined sewer overflows, and degradation of adjacent surface waters. Municipal environmental protection agencies have shown a growing interest in mitigating these effects with 'green' infrastructure practices that partially restore the perviousness and water holding capacity of urban centers. Assessment of the performance of current and future green infrastructure projects is hindered by the lack of adequate hydrological modeling tools; conventional techniques fail to account for the complex flow pathways of urban environments, and detailed analyses are difficult to prepare for the very large domains in which green infrastructure projects are implemented. Currently, no standard toolset exists that can rapidly and conveniently predict runoff, consequent inundations, and sewer overflows at a city-wide scale. We demonstrate how streamlined modeling techniques can be used with open-source GIS software to efficiently model runoff in large urban catchments. Hydraulic parameters and flow paths through city blocks, roadways, and sewer drains are automatically generated from GIS layers, and ultimately urban flow simulations can be executed for a variety of rainfall conditions. With this methodology, users can understand the implications of large-scale land use changes and green/gray storm water retention systems on hydraulic loading, peak flow rates, and runoff volumes.

Rapid runoff via shallow throughflow and deeper preferential flow in a boreal catchment underlain by frozen silt (Alaska, USA)

USGS Publications Warehouse

Koch, Joshua C.; Ewing, Stephanie A.; Striegl, Robert G.; McKnight, Diane M.

2013-01-01

In high-latitude catchments where permafrost is present, runoff dynamics are complicated by seasonal active-layer thaw, which may cause a change in the dominant flowpaths as water increasingly contacts mineral soils of low hydraulic conductivity. A 2-year study, conducted in an upland catchment in Alaska (USA) underlain by frozen, well-sorted eolian silt, examined changes in infiltration and runoff with thaw. It was hypothesized that rapid runoff would be maintained by flow through shallow soils during the early summer and deeper preferential flow later in the summer. Seasonal changes in soil moisture, infiltration, and runoff magnitude, location, and chemistry suggest that transport is rapid, even when soils are thawed to their maximum extent. Between June and September, a shift occurred in the location of runoff, consistent with subsurface preferential flow in steep and wet areas. Uranium isotopes suggest that late summer runoff erodes permafrost, indicating that substantial rapid flow may occur along the frozen boundary. Together, throughflow and deep preferential flow may limit upland boreal catchment water and solute storage, and subsequently biogeochemical cycling on seasonal to annual timescales. Deep preferential flow may be important for stream incision, network drainage development, and the release of ancient carbon to ecosystems

[Runoff loss of soil mineral nitrogen and its relationship with grass coverage on Loess slope land].

PubMed

Zhang, Yali; Li, Huai'en; Zhang, Xingchang; Xiao, Bo

2006-12-01

In a simulated rainfall experiment on Loess slope land, this paper determined the rainfall, surface runoff and the effective depth of interaction (EDI) between rainfall and soil mineral nitrogen, and studied the effects of grass coverage on the EDI and the runoff loss of soil mineral nitrogen. The results showed that with the increase of EDI, soil nitrogen in deeper layers could be released into surface runoff through dissolution and desorption. The higher the grass coverage, the deeper the EDI was. Grass coverage promoted the interaction between surface runoff and surface soil. On the slope land with 60%, 80% and 100% of grass coverage, the mean content of runoff mineral nitrogen increased by 34.52%, 32.67% and 6.00%, while surface runoff decreased by 4.72%, 9.84% and 12.89%, and eroded sediment decreased by 83.55%, 87.11% and 89.01%, respectively, compared with bare slope land. The total runoff loss of soil mineral nitrogen on the lands with 60%, 80%, and 100% of grass coverage was 95.73%, 109.04%, and 84.05% of that on bare land, respectively. Grass cover had dual effects on the surface runoff of soil mineral nitrogen. On one hand, it enhanced the influx of soil mineral nitrogen to surface runoff, and on the other hand, it markedly decreased the runoff, resulting in the decrease of soil mineral nitrogen loss through runoff and sediment. These two distinct factors codetermined the total runoff loss of soil mineral nitrogen.

Inevitable end-of-21st-century trends toward earlier surface runoff timing in California's Sierra Nevada Mountains

NASA Astrophysics Data System (ADS)

Schwartz, M. A.; Hall, A. D.; Sun, F.; Walton, D.; Berg, N.

2015-12-01

Hybrid dynamical-statistical downscaling is used to produce surface runoff timing projections for California's Sierra Nevada, a high-elevation mountain range with significant seasonal snow cover. First, future climate change projections (RCP8.5 forcing scenario, 2081-2100 period) from five CMIP5 global climate models (GCMs) are dynamically downscaled. These projections reveal that future warming leads to a shift toward earlier snowmelt and surface runoff timing throughout the Sierra Nevada region. Relationships between warming and surface runoff timing from the dynamical simulations are used to build a simple statistical model that mimics the dynamical model's projected surface runoff timing changes given GCM input or other statistically-downscaled input. This statistical model can be used to produce surface runoff timing projections for other GCMs, periods, and forcing scenarios to quantify ensemble-mean changes, uncertainty due to intermodel variability and consequences stemming from choice of forcing scenario. For all CMIP5 GCMs and forcing scenarios, significant trends toward earlier surface runoff timing occur at elevations below 2500m. Thus, we conclude that trends toward earlier surface runoff timing by the end-of-the-21st century are inevitable. The changes to surface runoff timing diagnosed in this study have implications for many dimensions of climate change, including impacts on surface hydrology, water resources, and ecosystems.

Nutrient transport in surface runoff and interflow from an aspen-birch forest

Treesearch

D.R. Timmons; E.S. Verry; R.E. Burwell; R.F. Holt

1977-01-01

Nutrients transported in surface runoff and interflow from an undisturbed aspen-birch (Populus tremuloides Michx., and Betula papyrifera Marsh.) forest (6.48 ha) in northern Minnesota were measured for 3 years. Surface runoff from snowmelt accounted for 97% of the average annual surface runoff and for 57% of the average annual...

Experimental study on soluble chemical transfer to surface runoff from soil.

PubMed

Tong, Juxiu; Yang, Jinzhong; Hu, Bill X; Sun, Huaiwei

2016-10-01

Prevention of chemical transfer from soil to surface runoff, under condition of irrigation and subsurface drainage, would improve surface water quality. In this paper, a series of laboratory experiments were conducted to assess the effects of various soil and hydraulic factors on chemical transfer from soil to surface runoff. The factors include maximum depth of ponding water on soil surface, initial volumetric water content of soil, depth of soil with low porosity, type or texture of soil and condition of drainage. In the experiments, two soils, sand and loam, mixed with different quantities of soluble KCl were filled in the sandboxes and prepared under different initial saturated conditions. Simulated rainfall induced surface runoff are operated in the soils, and various ponding water depths on soil surface are simulated. Flow rates and KCl concentration of surface runoff are measured during the experiments. The following conclusions are made from the study results: (1) KCl concentration in surface runoff water would decrease with the increase of the maximum depth of ponding water on soil surface; (2) KCl concentration in surface runoff water would increase with the increase of initial volumetric water content in the soil; (3) smaller depth of soil with less porosity or deeper depth of soil with larger porosity leads to less KCl transfer to surface runoff; (4) the soil with finer texture, such as loam, could keep more fertilizer in soil, which will result in more KCl concentration in surface runoff; and (5) good subsurface drainage condition will increase the infiltration and drainage rates during rainfall event and will decrease KCl concentration in surface runoff. Therefore, it is necessary to reuse drained fertile water effectively during rainfall, without polluting groundwater. These study results should be considered in agriculture management to reduce soluble chemical transfer from soil to surface runoff for reducing non-point sources pollution.

Flood damage claims reveal insights about surface runoff in Switzerland

NASA Astrophysics Data System (ADS)

Bernet, D. B.; Prasuhn, V.; Weingartner, R.

2015-12-01

A few case studies in Switzerland exemplify that not only overtopping water bodies frequently cause damages to buildings. Reportedly, a large share of the total loss due to flooding in Switzerland goes back to surface runoff that is formed and is propagating outside of regular watercourses. Nevertheless, little is known about when, where and why such surface runoff occurs. The described process encompasses surface runoff formation, followed by unchannelised overland flow until a water body is reached. It is understood as a type of flash flood, has short response times and occurs diffusely in the landscape. Thus, the process is difficult to observe and study directly. A promising source indicating surface runoff indirectly are houseowners' damage claims recorded by Swiss Public Insurance Companies for Buildings (PICB). In most of Switzerland, PICB hold a monopoly position and insure (almost) every building. Consequently, PICB generally register all damages to buildings caused by an insured natural hazard (including surface runoff) within the respective zones. We have gathered gapless flood related claim records of most of all Swiss PICB covering more than the last two decades on average. Based on a subset, we have developed a methodology to differentiate claims related to surface runoff from other causes. This allows us to assess the number of claims as well as total loss related to surface runoff and compare these to the numbers of overtopping watercourses. Furthermore, with the good data coverage, we are able to analyze surface runoff related claims in space and time, from which we can infer spatial and temporal characteristics of surface runoff. Although the delivered data of PICB are heterogeneous and, consequently, time-consuming to harmonize, our first results show that exploiting these damage claim records is feasible and worthwhile to learn more about surface runoff in Switzerland.

Analysis of factors controlling soil phosphorus loss with surface runoff in Huihe National Nature Reserve by principal component and path analysis methods.

PubMed

He, Jing; Su, Derong; Lv, Shihai; Diao, Zhaoyan; Bu, He; Wo, Qiang

2018-01-01

Phosphorus (P) loss with surface runoff accounts for the P input to and acceleration of eutrophication of the freshwater. Many studies have focused on factors affecting P loss with surface runoff from soils, but rarely on the relationship among these factors. In the present study, rainfall simulation on P loss with surface runoff was conducted in Huihe National Nature Reserve, in Hulunbeier grassland, China, and the relationships between P loss with surface runoff, soil properties, and rainfall conditions were examined. Principal component analysis and path analysis were used to analyze the direct and indirect effects on P loss with surface runoff. The results showed that P loss with surface runoff was closely correlated with soil electrical conductivity, soil pH, soil Olsen P, soil total nitrogen (TN), soil total phosphorus (TP), and soil organic carbon (SOC). The main driving factors which influenced P loss with surface runoff were soil TN, soil pH, soil Olsen P, and soil water content. Path analysis and determination coefficient analysis indicated that the standard multiple regression equation for P loss with surface runoff and each main factor was Y = 7.429 - 0.439 soil TN - 6.834 soil pH + 1.721 soil Olsen-P + 0.183 soil water content (r = 0.487, p < 0.01, n = 180). Soil TN, soil pH, soil Olsen P, and soil water content and the interactions between them were the main factors affecting P loss with surface runoff. The effect of physical and chemical properties of undisturbed soils on P loss with surface runoff was discussed, and the soil water content and soil Olsen P were strongly positive influences on the P loss with surface runoff.

Multiple modes of water quality impairment by fecal contamination in a rapidly developing coastal area: southwest Brunswick County, North Carolina.

PubMed

Cahoon, Lawrence B; Hales, Jason C; Carey, Erin S; Loucaides, Socratis; Rowland, Kevin R; Toothman, Byron R

2016-02-01

Fecal contamination of surface waters is a significant problem, particularly in rapidly developing coastal watersheds. Data from a water quality monitoring program in southwest Brunswick County, North Carolina, gathered in support of a regional wastewater and stormwater management program were used to examine likely modes and sources of fecal contamination. Sampling was conducted at 42 locations at 3-4-week intervals between 1996 and 2003, including streams, ponds, and estuarine waters in a variety of land use settings. Expected fecal sources included human wastewater systems (on-site and central), stormwater runoff, and direct deposition by animals. Fecal coliform levels were positively associated with rainfall measures, but frequent high fecal coliform concentrations at times of no rain indicated other modes of contamination as well. Fecal coliform levels were also positively associated with silicate levels, a groundwater source signal, indicating that flux of fecal-contaminated groundwater was a mode of contamination, potentially elevating FC levels in impacted waters independent of stormwater runoff. Fecal contamination by failing septic or sewer systems at many locations was significant and in addition to effects of stormwater runoff. Rainfall was also linked to fecal contamination by central sewage treatment system failures. These results highlight the importance of considering multiple modes of water pollution and different ways in which human activities cause water quality degradation. Management of water quality in coastal regions must therefore recognize diverse drivers of fecal contamination to surface waters.

Runoff production in a small agricultural catchment in Lao PDR : influence of slope, land-use and observation scale.

NASA Astrophysics Data System (ADS)

Patin, J.; Ribolzi, O.; Mugler, C.; Valentin, C.; Mouche, E.

2009-04-01

We study the surface and sub-surface hydrology of a small agricultural catchment (60ha) located in the Luang Prabang province of Lao PDR. This catchment is representative of the rural mountainous south east Asia. It exhibits steep slopes (up to 100% and more) under a monsoon climate. After years of traditional slash and burn cultures, it is now under high land pressures due to population resettling and environment preservation policies. This evolution leads to rapid land-use changes such as shifting cultivation reduction or growing of teak forest instead of classical crops. This catchment is a benchmark site of the Managing Soil Erosion Consortium since 1998. The international consortium aims to understand the effects of agricultural changes on the catchment hydrology and soil erosion in south east Asia. The Huay Pano catchment is subdivided into small sub-catchments that are gauged and monitored. Differ- ent agricultural practices where tested along the years. At a smaller scale, plot of 1m2 are instrumented to follow runoff and detachment of soil under natural rainfall along the monsoon season. Our modeling work aims to develop a distributed hydrological model integrating experimental data at the different scales. One of the objective is to understand the impact of land-use, soil properties (slope, crust, etc) and rainfall (dry and wet seasons) on surface and subsurface flows. We present here modeling results of the runoff plot experiments (1m2 scale) performed from 2002 to 2007. The plots distribution among the catchment and over the years gives a good representativity of the different runoff responses. The role of crust, slope and land-use on runoff is examined. Finally we discuss how this plot scale will be integrated in a sub-catchment model, with a particular attention on the observed paradox: how to explain that runoff coefficients at the catchment scale are much slower than at the plot scale ?

Effects of rainfall intensity and slope gradient on runoff and sediment yield characteristics of bare loess soil.

PubMed

Wu, Lei; Peng, Mengling; Qiao, Shanshan; Ma, Xiao-Yi

2018-02-01

Soil erosion is a universal phenomenon on the Loess Plateau but it exhibits complex and typical mechanism which makes it difficult to understand soil loss laws on slopes. We design artificial simulated rainfall experiments including six rainfall intensities (45, 60, 75, 90, 105, 120 mm/h) and five slopes (5°, 10°, 15°, 20°, 25°) to reveal the fundamental changing trends of runoff and sediment yield on bare loess soil. Here, we show that the runoff yield within the initial 15 min increased rapidly and its trend gradually became stable. Trends of sediment yield under different rainfall intensities are various. The linear correlation between runoff and rainfall intensity is obvious for different slopes, but the correlations between sediment yield and rainfall intensity are weak. Runoff and sediment yield on the slope surface both presents an increasing trend when the rainfall intensity increases from 45 mm/h to 120 mm/h, but the increasing trend of runoff yield is higher than that of sediment yield. The sediment yield also has an overall increasing trend when the slope changes from 5° to 25°, but the trend of runoff yield is not obvious. Our results may provide data support and underlying insights needed to guide the management of soil conservation planning on the Loess Plateau.

Soil Erosion in agro-industrially used Landscapes between High and Anti-Atlas

NASA Astrophysics Data System (ADS)

Peter, K. D.; Ries, J. B.; Marzolff, I.; d'Oleire-Oltmanns, S.

2012-04-01

The Souss basin is characterised by high population dynamics and changing land use. Extensive plantations of citrus fruits, bananas and vegetables in monocropping, mainly for the European market, replace the traditional mixed agriculture with small-area olive orchards and cereal fields. A precipitation of around 200 mm enforces the irrigation of cultivation by deep wells. The spatial vicinity of highly engineered irrigation areas, which are often created by land-levelling measures, and housing estates with highly active gully systems and rapid badland development presents a risk to both the agro-industrial land use and the population settlements. It is investigated whether the levelling measures influence surface runoff and soil erosion and thereby affect the further gully development. The influences of surface characteristics on runoff and soil erosion are analysed. Therefore 91 rainfall simulation experiments using a small portable rainfall simulator and 33 infiltrations by means of a single ring infiltrometer are carried out on seven test sites nearby the city of Taroudant. The rainfall simulations (30 minutes, 40 mm h-1) show an average runoff coefficient of between 54 and 59 % on test sites with land-levelling measures and average runoff coefficients ranging between 36 and 48 % on mostly non-levelled test sites. The average of soil erosion lies on levelled test sites between 52.1 and 81.8 g m-2, on non-levelled test-sites between 13.2 und 23.2 g m-2 per 30 minutes. Accordingly, all the test sites have a rather low infiltration capacity. This can also be confirmed by the low average infiltration depth of only 15.5 cm on levelled test sites. There is often a clear borderline at horizons with a high bulk density caused by compaction. In contrast, on non-levelled test sites, the average infiltration depth reaches 22.2 cm. Reinforcing factors for runoff and soil erosion are slope and soil crusts. Vegetation cover has a reducing influence on surface process activity. Medium rock fragment cover shows high rates of runoff and soil erosion. Hitherto collected data show an explicit difference between levelled and non-levelled test sites. Land-levelling measures clearly influence the generation of surface runoff and soil erosion and consequently, advance the further gully development.

[Effects of slopes on nitrogen transport along with runoff from sloping plots on a lateritic red soil amended with sewage sludge].

PubMed

Chen, Yan-Hui; Chen, Ming-Hua; Wang, Guo; Chen, Wen-Xiang; Yang, Shun-Cheng; Chai, Peng

2010-10-01

The effects of different slopes on nitrogen transport along with runoff from sloping plots amended with sewage sludge on a lateritic red soil were studied under simulated rainfall conditions. When the sludge was broadcasted and mixed with surface soils (BM), the MTN (total nitrogen of mixing sample), STN (total nitrogen of settled sample), TPN (total particulate nitrogen), TSN (total suspended nitrogen), TDN (total dissolved nitrogen) and NH4(+) -N concentrations and nitrogen loss amounts in runoff of all treatments were highest at 1 day or 18 days after application. The highest concentrations and the loss amounts of MTN and STN in the slope runoff for the BM treatment increased with slope degree, showing increasing pollution risks to the surface waters. The STN concentration and loss amounts from the 25 degrees plots were 126.1 mg x L(-1) and 1788.6 mg x m(-2), respectively, being 4.6 times and 5.8 times of the corresponding values from the 10 degrees plots, respectively. Then the concentrations and the loss amounts of nitrogen (except NO3(-) -N) from the BM plots diminished rapidly first and then tended to be stable with dwindling differences between the slopes. The loss of MTN and STN in early runoff (1 day and 18 days) accounted for 68.6% -73.4% and 62.3% -66.7% of the cumulative loss amounts during the experimental period for all the broadcasted treatments. Runoff loss coefficients of MTN increased in the order of 20 degrees > 25 degrees > 15 degrees > 10 degrees. Nitrogen was largely lost in dissolved species while large portion of NH4(+) -N was lost with particulates.

Modeling of storm runoff and pollutant wash off processes during storm event in rapidly urbanizing catchment

NASA Astrophysics Data System (ADS)

Qin, H. P.; Yu, X. Y.; Khu, S. T.

2009-04-01

Many urban catchments in developing countries are undergoing fast economic growth, population expansion and land use/cover change. Due to the mixture of agricultural/industrial/residential land use or different urbanization level as well as lack of historical monitoring data in the developing area, storm-water runoff pollution modeling is faced with challenges of considerable spatial variations and data insufficiency. Shiyan Reservoir catchment is located in the rapidly urbanizing coastal region of Southeast China. It has six sub-catchments with largely different land use patterns and urbanization levels. A simple semi-distributed model was used to simulate the storm-water runoff pollution process during storm event in the catchment. The model adopted modified IHACRES model and exponential wash-off functions to describe storm-runoff and pollutant wash-off processes, respectively, in each of six sub-catchments. Temporary hydrological and water quality monitoring sites were set at the downstream section of each sub-catchment in Feb-May 2007, spanning non-rain and rain seasons. And the model was calibrated for storm-runoff and water quality data during two typical storm events with rainfall amount of 10mm/4hr and 73mm/5hr, respectively. The results indicated that the Nash-Sutcliffe (NS) coefficients are greater than 0.65 and 0.55 respectively for storm-runoff model calibration and validation. However although NS coefficients can reach 0.7~0.9 for pollutant wash-off model calibration based on measured data in each storm event, the simulation data can not fit well with the measured data in model validation. According to field survey observation, many litters and residuals were found to distribute in disorder in some sub-catchments or their drainage systems and to instantaneously wash off into the surface water when the rainfall amount and intensity are large enough. In order to improve storm-water runoff pollution simulation in the catchment, the variations of pollutant source and wash off processes in different storm intensity should be consider in future monitoring and model development. Keywords: storm runoff; wash off; urbanization; catchment modeling; litter; residual

Modeling the Effect of Summertime Heating on Urban Runoff Temperature

NASA Astrophysics Data System (ADS)

Thompson, A. M.; Gemechu, A. L.; Norman, J. M.; Roa-Espinosa, A.

2007-12-01

Urban impervious surfaces absorb and store thermal energy, particularly during warm summer months. During a rainfall/runoff event, thermal energy is transferred from the impervious surface to the runoff, causing it to become warmer. As this higher temperature runoff enters receiving waters, it can be harmful to coldwater habitat. A simple model has been developed for the net energy flux at the impervious surfaces of urban areas to account for the heat transferred to runoff. Runoff temperature is determined as a function of the physical characteristics of the impervious areas, the weather, and the heat transfer between the moving film of runoff and the heated impervious surfaces that commonly exist in urban areas. Runoff from pervious surfaces was predicted using the Green- Ampt Mein-Larson infiltration excess method. Theoretical results were compared to experimental results obtained from a plot-scale field study conducted at the University of Wisconsin's West Madison Agricultural Research Station. Surface temperatures and runoff temperatures from asphalt and sod plots were measured throughout 15 rainfall simulations under various climatic conditions during the summers of 2004 and 2005. Average asphalt runoff temperatures ranged from 23.2°C to 37.1°C. Predicted asphalt runoff temperatures were in close agreement with measured values for most of the simulations (average RMSE = 4.0°C). Average pervious runoff temperatures ranged from 19.7° to 29.9°C and were closely approximated by the rainfall temperature (RMSE = 2.8°C). Predicted combined asphalt and sod runoff temperatures using a flow-weighted average were in close agreement with observed values (average RMSE = 3.5°C).

Rainfall-runoff properties of tephra: Simulated effects of grain-size and antecedent rainfall

NASA Astrophysics Data System (ADS)

Jones, Robbie; Thomas, Robert E.; Peakall, Jeff; Manville, Vern

2017-04-01

Rain-triggered lahars (RTLs) are a significant and often persistent secondary volcanic hazard at many volcanoes around the world. Rainfall on unconsolidated volcaniclastic material is the primary initiation mechanism of RTLs: the resultant flows have the potential for large runout distances (> 100 km) and present a substantial hazard to downstream infrastructure and communities. RTLs are frequently anticipated in the aftermath of eruptions, but the pattern, timing and scale of lahars varies on an eruption-by-eruption and even catchment-by-catchment basis. This variability is driven by a set of local factors including the grain size distribution, thickness, stratigraphy and spatial distribution of source material in addition to topography, vegetation coverage and rainfall conditions. These factors are often qualitatively discussed in RTL studies based on post-eruption lahar observations or instrumental detections. Conversely, this study aims to move towards a quantitative assessment of RTL hazard in order to facilitate RTL predictions and forecasts based on constrained rainfall, grain size distribution and isopach data. Calibrated simulated rainfall and laboratory-constructed tephra beds are used within a repeatable experimental set-up to isolate the effects of individual parameters and to examine runoff and infiltration processes from analogous RTL source conditions. Laboratory experiments show that increased antecedent rainfall and finer-grained surface tephra individually increase runoff rates and decrease runoff lag times, while a combination of these factors produces a compound effect. These impacts are driven by increased residual moisture content and decreased permeability due to surface sealing, and have previously been inferred from downstream observations of lahars but not identified at source. Water and sediment transport mechanisms differ based on surface grain size distribution: a fine-grained surface layer displayed airborne remobilisation, accretionary pellet formation, rapid surface sealing and infiltration-excess overland flow generation whilst a coarse surface layer demonstrated exclusively rainsplash-driven particle detachment throughout the rainfall simulations. This experimental protocol has the potential to quantitatively examine the effects of a variety of individual parameters in RTL initiation under controlled conditions.

Mechanisms of surface runoff genesis on a subsurface drained soil affected by surface crusting: A field investigation

NASA Astrophysics Data System (ADS)

Augeard, Bénédicte; Kao, Cyril; Chaumont, Cédric; Vauclin, Michel

Artificial drainage has been subject to widespread criticism because of its impact on water quality and because there is suspicion that it may have detrimental effects on flood genesis. The present work aims at a better understanding of the mechanisms controlling infiltration and surface runoff genesis, particularly in soils with artificial drainage and affected by surface crusting. A field experiment was conducted during one drainage season (November 2003-March 2004) in the Brie region (80 km east of Paris, France) on a subsurface drained silty soil. Water table elevation and surface runoff were monitored above the drain and at midpoint between drains. Soil water pressure head was measured at various depths and locations between the midpoint and the drain. Soil surface characteristics (microtopography and degree of structural and sedimentary crust development) were recorded regularly on the experimental site and on other plots of various drainage intensities. The results show that the first surface runoff events were induced by high water table. However, runoff was higher at midpoint between the drains because water table reached the soil surface at that point, thus considerably reducing infiltration capacity compared to that above the drain. Comparing different plots, the area with older drainage installation (1948) yielded the most surface runoff. Wider drain spacing, smaller drain depth and possible plugging may have led to a greater area of saturated soil between drains. During the winter period, the impact of raindrops induced the formation of a structural crust on the soil surface. Furthermore, the development of the sedimentary crust, which was favored by water actually flowing on the soil surface during the high water table periods could be correlated with surface runoff volume. The formation of this crust had a significant impact on runoff occurrence at the end of the winter. Therefore, poorly drained fields presented more favorable conditions for both Horton type runoff and saturation excess runoff. Drainage effectively reduces surface runoff occurrences not only by lowering the water table in winter but also by limiting soil surface sealing.

Prairie and turf buffer strips for controlling runoff from paved surfaces.

PubMed

Steinke, K; Stier, J C; Kussow, W R; Thompson, A

2007-01-01

Eutrophication of surface waters due to nonpoint source pollution from urban environments has raised awareness of the need to decrease runoff from roads and other impervious surfaces. These concerns have led to precautionary P application restrictions on turf and requirements for vegetative buffer strips. The impacts of two plant communities and three impervious/pervious surface ratios were assessed on runoff water quality and quantity. A mixed forb/grass prairie and a Kentucky bluegrass (Poa pratensis L.) blend were seeded and runoff was monitored and analyzed for total volume, total P, soluble P, soluble organic P, bioavailable P, total suspended solids, and total organic suspended solids. Mean annual runoff volumes, all types of mean annual P nutrient losses, and sediment loads were not significantly affected by treatments because over 80% of runoff occurred during frozen soil conditions. Total P losses from prairie and turf were similar, averaging 1.96 and 2.12 kg ha(-1) yr(-1), respectively. Vegetation appeared to be a likely contributor of nutrients, particularly from prairie during winter dormancy. When runoff occurred during non-frozen soil conditions turf allowed significantly (P < or = 0.10) lower runoff volumes compared with prairie vegetation and the 1:2 and 1:4 impervious/pervious surface ratios had less runoff than the 1:1 ratio (P < or = 0.05). In climates where the majority of runoff occurs during frozen ground conditions, vegetative buffers strips alone are unlikely to dramatically reduce runoff and nutrient loading into surface waters. Regardless of vegetation type or size, natural nutrient biogeochemical cycling will cause nutrient loss in surface runoff waters, and these values may represent baseline thresholds below which values cannot be obtained.

Do upslope impervious surfaces impact the run-on/runoff relationship?

USDA-ARS?s Scientific Manuscript database

Development of watersheds previously managed for agricultural uses for commercial and residential uses results in the replacement of pervious soil surfaces with impervious surfaces. Characteristics of runoff generated on new upslope impervious surfaces may differ from runoff generated on the predeve...

Use of isotopically labeled fertilizer to trace nitrogen fertilizer contributions to surface, soil, and ground water

USGS Publications Warehouse

Wilkison, D.H.; Blevins, D.W.; Silva, S.R.

2000-01-01

The fate and transport of a single N fertilizer application through plants, soil, runoff, and the unsaturated and saturated zones was determined for four years at a field site under continuous corn (Zea mays L.) management. Claypan soils, which underlie the site, were hypothesized to restrict the movement of agrichemicals from the soil surface to ground water. However, N fertilizer moved rapidly through preferential flow paths in the soil and into the underlying glacial till aquifer. Most N transport occurred during the fall and winter when crops were not available to use excess N. Forty months after application, 33 percent of the fertilizer had been removed by grain harvests, 30 percent had been transpired to the atmosphere, and 33 percent had migrated to ground water. Although runoff volumes were 50 percent greater than infiltration, less than 2 percent of the fertilizer was lost to runoff. Small measured denitrification rates and large measured dissolved oxygen concentrations in ground water favor the long-term stability of NO3-1 in ground water. Successive fertilizer applications, in areas that lack the ability to moderate N concentrations through consumptive N reactions, risk the potential of N-saturated ecosystems.

Transport of oxytetracycline, chlortetracycline, and ivermectin in surface runoff from irrigated pasture.

PubMed

Bair, Daniel A; Popova, Ina E; Tate, Kenneth W; Parikh, Sanjai J

2017-09-02

The transport of oxytetracycline, chlortetracycline, and ivermectin from manure was assessed via surface runoff on irrigated pasture. Surface runoff plots in the Sierra Foothills of Northern California were used to evaluate the effects of irrigation water application rates, pharmaceutical application conditions, vegetative cover, and vegetative filter strip length on the pharmaceutical discharge in surface runoff. Experiments were designed to permit the maximum potential transport of pharmaceuticals to surface runoff water, which included pre-irrigation to saturate soil, trimming grass where manure was applied, and laying a continuous manure strip perpendicular to the flow of water. However, due to high sorption of the pharmaceuticals to manure and soil, less than 0.1% of applied pharmaceuticals were detected in runoff water. Results demonstrated an increase of pharmaceutical transport in surface runoff with increased pharmaceutical concentration in manure, the concentration of pharmaceuticals in runoff water remained constant with increased irrigation flow rate, and no appreciable decrease in pharmaceutical runoff was produced with the vegetative filter strip length increased from 30.5 to 91.5 cm. Most of the applied pharmaceuticals were retained in the manure or within the upper 5 cm of soil directly beneath the manure application sites. As this study evaluated conditions for high transport potential, the data suggest that the risk for significant chlortetracycline, oxytetracycline, and ivermectin transport to surface water from cattle manure on irrigated pasture is low.

A method of determining surface runoff by

Treesearch

Donald E. Whelan; Lemuel E. Miller; John B. Cavallero

1952-01-01

To determine the effects of watershed management on flood runoff, one must make a reliable estimate of how much the surface runoff can be reduced by a land-use program. Since surface runoff is the difference between precipitation and the amount of water that soaks into the soil, such an estimate must be based on the infiltration capacity of the soil.

Seasonal variability of salinity, temperature, turbidity and suspended chlorophyll in the Tweed Estuary.

PubMed

Uncles, R J; Bloomer, N J; Frickers, P E; Griffiths, M L; Harris, C; Howland, R J; Morris, A W; Plummer, D H; Tappin, A D

2000-05-05

Results are presented from a campaign of measurements that were undertaken to examine seasonal variability in physical and chemical fluxes and processes within the Tweed Estuary during the period September 1996-August 1997. The study utilised monthly surveys, each of approximately 1 week duration. This article interprets a subset of the salinity, temperature, turbidity [suspended particulate matter (SPM) levels] and chlorophyll a data. Measurements discussed here were obtained throughout the estuary during high-speed transects that covered the region between the tidal river and the coastal zone. Longitudinal distributions of surface salinity depended strongly on freshwater runoff. During high runoff the surface salinity was low and the freshwater-saltwater interface (FSI) was located close to the mouth. The reverse was true at times of low runoff. Salinity stratification was generally strong. During the surveys, river runoff temperatures ranged from approximately 2 to 18 degrees C and coastal waters (approximately 33 salinity) from approximately 6 to 15 degrees C. Turbidity was low throughout the campaign (SPM < 30 mg l(-1)). Because of rapid flushing times (one or two tides), turbidity tended to mix conservatively between river and coastal waters. Higher coastal turbidity was associated with stronger wind events, and higher fluvial turbidity with spate events. Suspended chlorophyll a levels were usually low throughout the estuary (typically < 2 microg l(-1)) and showed large spatial variability. Because of the rapid flushing of the estuary, it is hypothesised that it was not possible for several algal cell divisions to occur before algae were flushed to the coastal zone. A 'bloom' occurred during the May 1997 survey, when chlorophyll a levels reached 14 microg l(-1). Higher chlorophyll a concentrations at that time occurred at very low salinities, indicating that these waters and algae were largely fluvially derived, and may have resulted from increasing springtime solar irradiation.

Mitigation of nutrient losses via surface runoff from rice cropping systems with alternate wetting and drying irrigation and site-specific nutrient management practices.

PubMed

Liang, X Q; Chen, Y X; Nie, Z Y; Ye, Y S; Liu, J; Tian, G M; Wang, G H; Tuong, T P

2013-10-01

Resource-conserving irrigation and fertilizer management practices have been developed for rice systems which may help address water quality concerns by reducing N and P losses via surface runoff. Field experiments under three treatments, i.e., farmers' conventional practice (FCP), alternate wetting and drying (AWD), and AWD integrated with site-specific nutrient management (AWD + SSNM) were carried out during two rice seasons at two sites in the southwest Yangtze River delta region. Across site years, results indicated that under AWD irrigation (i.e., AWD and AWD + SSNM), water inputs were reduced by 13.4~27.5 % and surface runoff was reduced by 30.2~36.7 % compared to FCP. When AWD was implemented alone, total N and P loss masses via surface runoff were reduced by 23.3~30.4 % and 26.9~31.7 %, respectively, compared to FCP. However, nutrient concentrations of surface runoff did not decrease under AWD alone. Under AWD + SSNM, total N and P loss masses via surface runoff were reduced to a greater extent than AWD alone (39.4~47.6 % and 46.1~48.3 % compared to FCP, respectively), while fertilizer inputs and N surpluses significantly decreased and rice grain yields increased relative to FCP. Therefore, by more closely matching nutrient supply with crop demand and reducing both surface runoff and nutrient concentrations of surface runoff, our results demonstrate that integration of AWD and SSNM practices can mitigate N and P losses via surface runoff from rice fields while maintaining high yields.

Transport of trace metals in runoff from soil and pond ash feedlot surfaces

USGS Publications Warehouse

Vogel, J.R.; Gilley, J.E.; Cottrell, G.L.; Woodbury, B.L.; Berry, E.D.; Eigenbert, R.A.

2011-01-01

The use of pond ash (fly ash that has been placed in evaporative ponds for storage and subsequently dewatered) for feedlot surfaces provides a drier environment for livestock and furnishes economic benefits. However, pond ash is known to have high concentrations of trace elements, and the runoff water-quality effects of feedlot surfaces amended with pond ash are not well defined. For this study, two experimental units (plots) were established in eight feedlot pens. Four of the pens contained unamended soil surfaces, and the remaining four pens had pond-ash amended surfaces. Before each test, unconsolidated surface material was removed from four of the plots for each of the amendment treatments, resulting in eight unamended plots and eight pond-ash amended plots. Concentrations for 23 trace elements were measured in cattle feedlot surface material and in the runoff water from three simulated rainfall events. Trace element concentrations in surface material and runoff did not differ between surface consolidation treatments. Amending the feedlot surface material with pond ash resulted in a significant increase in concentration for 14 of the 17 trace elements. Runoff concentrations for 21 trace elements were affected by pond-ash amendment. Sixteen of 21 trace element concentrations that differed significantly were greater in runoff from unamended soil surfaces. Concentrations in runoff were significantly correlated with concentrations in feedlot surface material for boron, manganese, molybdenum, selenium, and uranium.

Modeling phosphorus losses from soils amended with cattle manures and chemical fertilizers.

PubMed

Wang, Zhaozhi; Zhang, T Q; Tan, C S; Vadas, P; Qi, Z M; Wellen, C

2018-05-22

While applied manure/fertilizer is an important source of P loss in surface runoff, few models simulate the direct transfer of phosphorus (P) from soil-surface-applied manure/fertilizer to surface runoff. The SurPhos model was tested with 2008-2010 growing season daily surface runoff data from clay loam experimental plots subject to different manure/fertilizer applications. Model performance was evaluated on the basis of the coefficient of determination (R 2 ), Nash-Sutcliffe efficiency (NSE), percent bias (PBIAS), and the ratio of the root mean square error to the standard deviation of observed values (RSR). The model offered an acceptable performance in simulating soil labile P dynamics (R 2  = 0.75, NSE = 0.55, PBIAS = 10.43%, and RSR = 0.67) and dissolved reactive P (DRP) loss in surface runoff (R 2  ≥ 0.74 and NSE ≥ 0.69) for both solid and liquid cattle manure, as well as inorganic fertilizer. Simulated direct P loss in surface runoff from solid and liquid cattle manure accounted for 39% and 40% of total growing season DRP losses in surface runoff. To compensate for the unavailability of daily surface runoff observations under snow melt condition, the whole four years' (2008-2011) daily surface runoff predicted by EPIC (Environmental Policy Integrated Climate) was used as SurPhos input. The accuracy of simulated DRP loss in surface runoff under the different manure/fertilizer treatments was acceptable (R 2  ≥ 0.55 and NSE ≥ 0.50). For the solid cattle manure treatment, of all annual DRP losses, 19% were derived directly from the manure. Beyond offering a reliable prediction of manure/fertilizer P loss in surface runoff, SurPhos quantified different sources of DRP loss and dynamic labile P in soil, allowing a better critical assessment of different P management measures' effectiveness in mitigating DRP losses. Copyright © 2018 Elsevier B.V. All rights reserved.

Adhesion of and to soil in runoff as influenced by polyacrylamide.

PubMed

Bech, Tina B; Sbodio, Adrian; Jacobsen, Carsten S; Suslow, Trevor

2014-11-01

Polyacrylamide (PAM) is used in agriculture to reduce soil erosion and has been reported to reduce turbidity, nutrients, and pollutants in surface runoff water. The objective of this work was to determine the effect of PAM on the concentration of enteric bacteria in surface runoff by comparing four enteric bacteria representing phenotypically different motility and hydrophobicity from three soils. Results demonstrated that bacterial surface runoff was differentially influenced by the PAM treatment. Polyacrylamide treatment increased surface runoff for adhered and planktonic cells from a clay soil; significantly decreased surface runoff of adhered bacteria, while no difference was observed for planktonic bacteria from the sandy loam; and significantly decreased the surface runoff of planktonic cells, while no difference was observed for adhered bacteria from the clay loam. Comparing strains from a final water sample collected after 48 h showed a greater loss of while serovar Poona was almost not detected. Thus, (i) the PAM efficiency in reducing the concentration of enteric bacteria in surface runoff was influenced by soil type and (ii) variation in the loss of enteric bacteria highlights the importance of strain-specific properties that may not be captured with general fecal indicator bacteria. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Geologic framework and hydrogeologic characteristics of the Edwards aquifer outcrop (Barton Springs segment), northeastern Hays and southwestern Travis Counties, Texas

USGS Publications Warehouse

Small, Ted A.; Hanson, John A.; Hauwert, Nico M.

1996-01-01

In the Barton Springs segment of the Edwards aquifer, the aquifer probably is most vulnerable to surface contamination in the rapidly urbanizing areas on the Edwards aquifer outcrop. Contamination can result from spills or leakage of hazardous materials; or runoff on the intensely faulted and fractured, karstic limestone outcrops characteristic of the recharge zone.

Analyzing the causes of urban waterlogging and sponge city technology in China

NASA Astrophysics Data System (ADS)

Ning, Yun-Fang; Dong, Wen-Yi; Lin, Lu-Sheng; Zhang, Qian

2017-03-01

With the rapid development of social economy in China, increased urban population, and rapid urbanization cause serious problems, for example, a heavy rain in the city inevitably leads to waterlogging, which poses a great threat to the livelihood and property security. Disaster due to urban flood is a key problem that restricts the development of urban ecology in China. The reason is the sharp increase of impermeable surface ratio in urban areas, leading to a decrease in rainfall infiltration and increase in surface runoff. To effectively solve the urban waterlogging, China proposed the construction of sponge city. This paper analyzes and summarizes the reasons for the formation of urban waterlogging, and introduces the concept of the sponge city technology to prevent waterlogging.

Characteristics of storm runoff and sediment dispersal in the San Pedro Channel, southern California.

PubMed

Ahn, J H; Grant, S B

2007-01-01

In-site measurements of particle size spectra were obtained from three offshore cruises to evaluate the physical consequences of increased sediment transport and deposition offshore which was caused by episodic storm runoff water from the Santa Ana River watershed, a highly urbanised coastal watershed in southern California. Of the total annual runoff discharge to the coastal ocean, 89.2% occurred in the 2003/2004 winter season, and 0.22 Mt of sediment mass was transported during the storm events. The runoff plume at surface taken offshore by cross-shore currents progressed rapid aggregation and sedimentation, while the initially high concentration of suspended sediment discharged from the river outlet was dominated by small particles. Vertical profiles of particle size spectra revealed two separated plumes near the river outlet and turbidity plume along the bottom consisted of an abundance of very fine and dense particles. It would appear to support the theory that even if the storm runoff does not carry a high concentration of sediment being capable of generating negative buoyancy, sediment deposition on the shelf might mobilise in dense, fluid mud transported offshore by gravity. In a coastal pollution context, sediment particle size spectra information may offer potentially useful means of characterising particle-associated pollutants for purposes of source tracking and environmental interpretation.

Imposing constraints on parameter values of a conceptual hydrological model using baseflow response

NASA Astrophysics Data System (ADS)

Dunn, S. M.

Calibration of conceptual hydrological models is frequently limited by a lack of data about the area that is being studied. The result is that a broad range of parameter values can be identified that will give an equally good calibration to the available observations, usually of stream flow. The use of total stream flow can bias analyses towards interpretation of rapid runoff, whereas water quality issues are more frequently associated with low flow condition. This paper demonstrates how model distinctions between surface an sub-surface runoff can be used to define a likelihood measure based on the sub-surface (or baseflow) response. This helps to provide more information about the model behaviour, constrain the acceptable parameter sets and reduce uncertainty in streamflow prediction. A conceptual model, DIY, is applied to two contrasting catchments in Scotland, the Ythan and the Carron Valley. Parameter ranges and envelopes of prediction are identified using criteria based on total flow efficiency, baseflow efficiency and combined efficiencies. The individual parameter ranges derived using the combined efficiency measures still cover relatively wide bands, but are better constrained for the Carron than the Ythan. This reflects the fact that hydrological behaviour in the Carron is dominated by a much flashier surface response than in the Ythan. Hence, the total flow efficiency is more strongly controlled by surface runoff in the Carron and there is a greater contrast with the baseflow efficiency. Comparisons of the predictions using different efficiency measures for the Ythan also suggest that there is a danger of confusing parameter uncertainties with data and model error, if inadequate likelihood measures are defined.

What controls the very quick runoff response in the Meuse basin?

NASA Astrophysics Data System (ADS)

Bouaziz, Laurène; Hrachowitz, Markus; Schellekens, Jaap; Weerts, Albrecht; Savenije, Hubert

2017-04-01

Currently, the hydrological model used in the operational forecasting system of the river Meuse is lumped and does not account for the heterogeneity of the landscape, topography and vegetation. Previous studies have shown the importance of model structure distribution in different hydrological response units (HRUs) to improve model simulations. These HRUs take into account the different dominant runoff generation processes that occur in different parts of the landscape. The conceptualization of a runoff response with a very rapid time scale is essential to model the rapid runoff generated by very high intensity rainfall events. The parameterization of this rapid runoff response in the different sub-catchments of the Meuse is very sensitive due to the non-linearity of this threshold process and to the spatio-temporal variability of high-intensity rain events. In this study, we formulate several hypotheses on what controls the very quick runoff response in the Meuse basin and we try to use additional sources of data to test the a-priori assumptions that we made in the conceptualization of the HRUs in our hydrological model and to facilitate model parameterization. We hypothesize that by using appropriate runoff signatures, we may be able to assess the importance of the threshold response in the different catchments. The selection of specific storm events is useful to split the runoff in different time scales to improve the a-priori estimation of the very rapid runoff parameterization. Linking these differences to topographic and physiographic properties of the catchment like soil texture and land use may help us to explain the difference in observed spatial patterns. Especially the assessment of the fraction of roads and paved areas that cross the different hydrological response units may help to explain the observed spatial patterns. Additionally, we believe that deriving permanent and temporary wet areas using the Modified Normalized Difference Water Index (MNDWI) may guide us in strengthening or adapting the assumptions we made concerning the HRU classes.

Input and fate of anthropogenic estrogens and gadolinium in surface water and sewage plants in the hydrological basin of Prague (Czech Republic).

PubMed

Morteani, Giulio; Möller, Peter; Fuganti, Andrea; Paces, Tomas

2006-06-01

The concentration of the estrogens 17beta-estradiol, estriol, estrone, 17alpha-ethinylestradiol, mestranol and norethisterone and of the anthropogenic gadolinium (Gd(ant)) has been determined in the creeks and rivers, sewage treatment plants and water works of the city of Prague. The rapid degradation of estrogens in surface water allows the estrogen concentration gradient to be used as a very precise and sensitive guideline by which to pin-point sewage leaks into surface run-off water. The rather conservative behavior of Gd(ant) in surface and ground water documents in the present case the presence of sewage water in the surface water cycle.

Assessment of Runoff Toxicity from Coated Surfaces

EPA Science Inventory

Presented in this paper are results from a field and laboratory study of the potential runoff toxicity from coated surfaces. The study results qualified and quantified the types and concentrations of pollutants in runoff from surfaces sealed with a variety of products. Coatings a...

Simulating high frequency water quality monitoring data using a catchment runoff attenuation flux tool (CRAFT).

PubMed

Adams, Russell; Quinn, Paul F; Perks, Matthew; Barber, Nicholas J; Jonczyk, Jennine; Owen, Gareth J

2016-12-01

High resolution water quality data has recently become widely available from numerous catchment based monitoring schemes. However, the models that can reproduce time series of concentrations or fluxes have not kept pace with the advances in monitoring data. Model performance at predicting phosphorus (P) and sediment concentrations has frequently been poor with models not fit for purpose except for predicting annual losses. Here, the data from the Eden Demonstration Test Catchments (DTC) project have been used to calibrate the Catchment Runoff Attenuation Flux Tool (CRAFT), a new, parsimonious model developed with the aim of modelling both the generation and attenuation of nutrients and sediments in small to medium sized catchments. The CRAFT has the ability to run on an hourly timestep and can calculate the mass of sediments and nutrients transported by three flow pathways representing rapid surface runoff, fast subsurface drainage and slow groundwater flow (baseflow). The attenuation feature of the model is introduced here; this enables surface runoff and contaminants transported via this pathway to be delayed in reaching the catchment outlet. It was used to investigate some hypotheses of nutrient and sediment transport in the Newby Beck Catchment (NBC) Model performance was assessed using a suite of metrics including visual best fit and the Nash-Sutcliffe efficiency. It was found that this approach for water quality models may be the best assessment method as opposed to using a single metric. Furthermore, it was found that, when the aim of the simulations was to reproduce the time series of total P (TP) or total reactive P (TRP) to get the best visual fit, that attenuation was required. The model will be used in the future to explore the impacts on water quality of different mitigation options in the catchment; these will include attenuation of surface runoff. Copyright © 2016 Elsevier B.V. All rights reserved.

Surface Runoff of Pesticides from a Clay Loam Field in Sweden.

PubMed

Larsbo, Mats; Sandin, Maria; Jarvis, Nick; Etana, Ararso; Kreuger, Jenny

2016-07-01

Pesticides stored at or close to the soil surface after field application can be mobilized and transported off the field when surface runoff occurs. The objective of our study was to quantify the potential pesticide losses in surface runoff from a conventionally managed agricultural field in a Swedish climate. This was achieved by measuring surface runoff volumes and concentrations in runoff of six spring-applied pesticides and autumn-applied glyphosate and its metabolite aminomethylphosphonic acid (AMPA). Measurements were performed for 3 yr both during the growing seasons and during intervening winter snowmelt periods on a clay loam field close to Uppsala. During growing seasons, surface runoff was generated on only five occasions during one 25-d period in 2012 when the infiltration capacity of the soil may have been reduced by structural degradation due to large cumulative rainfall amounts after harrowing. Concentrations in surface runoff exceeded Swedish water quality standards in all samples during this growing season for diflufenican and pirimicarb. Surface runoff was generated during three snowmelt periods during the winter of 2012-2013. All of the applied pesticides were found in snowmelt samples despite incorporation of residues by autumn plowing, degradation, and leaching into the soil profile during the period between spraying and sampling. Concentrations of glyphosate ranged from 0.12 to 7.4 μg L, and concentrations of AMPA ranged from 0 to 2.7 μg L. Our results indicate that temporal changes in hydraulic properties during the growing season and when the soil freezes during winter affect pesticide losses through surface runoff. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

EVALUATION OF TOXICS IN RUNOFF FROM COATED SURFACES

EPA Science Inventory

Presented in this paper are results from a field and laboratory study of the potential runoff toxicity from coated surfaces. The study results qualified and quantified the types and concentrations of pollutants in runoff from surfaces sealed with a variety of products. Coatings a...

Watershed Analysis for Runoff and Erosion Potential on Santa Cruz Watershed: Impact of Climate and Land Cover Changes

EPA Science Inventory

Many empirical studies have established the significant relationship between climate and runoff: climate change may potentially increase or decrease the surface runoff. Increased surface runoff can also increase the risk of soil erosion. Land cover change can alter rainfall-runof...

A laboratory study of colloid and solute transport in surface runoff on saturated soil

NASA Astrophysics Data System (ADS)

Yu, Congrong; Gao, Bin; Muñoz-Carpena, Rafael; Tian, Yuan; Wu, Lei; Perez-Ovilla, Oscar

2011-05-01

SummaryColloids in surface runoff may pose risks to the ecosystems not only because some of them (e.g., pathogens) are toxic, but also because they may facilitate the transport of other contaminants. Although many studies have been conducted to explore colloid fate and transport in the environment, current understanding of colloids in surface runoff is still limited. In this study, we conducted a range of laboratory experiments to examine the transport behavior of colloids in a surface runoff system, made of a soil box packed with quartz sand with four soil drainage outlets and one surface flow outlet. A natural clay colloid (kaolinite) and a conservative chemical tracer (bromide) were applied to the system under a simulated rainfall event (64 mm/h). Effluent soil drainage and surface flow samples were collected to determine the breakthrough concentrations of bromide and kaolinite. Under the experimental conditions tested, our results showed that surface runoff dominated the transport processes. As a result, kaolinite and bromide were found more in surface flow than in soil drainage. Comparisons between the breakthrough concentrations of bromide and kaolinite showed that kaolinite had lower mobility than bromide in the subsurface flow (i.e., soil drainage), but behaved almost identical to bromide in the surface runoff. Student's t-test confirmed the difference between kaolinite and bromide in subsurface flow ( p = 0.02). Spearman's test and linear regression analysis, however, showed a strong 1:1 correlation between kaolinite and bromide in surface runoff ( p < 0.0001). Our result indicate that colloids and chemical solutes may behave similarly in overland flow on bare soils with limited drainage when surface runoff dominates the transport processes.

Phosphorus runoff from incorporated and surface-applied liquid swine manure and phosphorus fertilizer.

PubMed

Daverede, I C; Kravchenko, A N; Hoeft, R G; Nafziger, E D; Bullock, D G; Warren, J J; Gonzini, L C

2004-01-01

Excessive fertilization with organic and/or inorganic P amendments to cropland increases the potential risk of P loss to surface waters. The objective of this study was to evaluate the effects of soil test P level, source, and application method of P amendments on P in runoff following soybean [Glycine max (L.) Merr.]. The treatments consisted of two rates of swine (Sus scrofa domestica) liquid manure surface-applied and injected, 54 kg P ha(-1) triple superphosphate (TSP) surface-applied and incorporated, and a control with and without chisel-plowing. Rainfall simulations were conducted one month (1MO) and six months (6MO) after P amendment application for 2 yr. Soil injection of swine manure compared with surface application resulted in runoff P concentration decreases of 93, 82, and 94%, and P load decreases of 99, 94, and 99% for dissolved reactive phosphorus (DRP), total phosphorus (TP), and algal-available phosphorus (AAP), respectively. Incorporation of TSP also reduced P concentration in runoff significantly. Runoff P concentration and load from incorporated amendments did not differ from the control. Factors most strongly related to P in runoff from the incorporated treatments included Bray P1 soil extraction value for DRP concentration, and Bray P1 and sediment content in runoff for AAP and TP concentration and load. Injecting manure and chisel-plowing inorganic fertilizer reduced runoff P losses, decreased runoff volumes, and increased the time to runoff, thus minimizing the potential risk of surface water contamination. After incorporating the P amendments, controlling erosion is the main target to minimize TP losses from agricultural soils.

Characterizing dry deposition of mercury in urban runoff

USGS Publications Warehouse

Fulkerson, M.; Nnadi, F.N.; Chasar, L.S.

2007-01-01

Stormwater runoff from urban surfaces often contains elevated levels of toxic metals. When discharged directly into water bodies, these pollutants degrade water quality and impact aquatic life and human health. In this study, the composition of impervious surface runoff and associated rainfall was investigated for several storm events at an urban site in Orlando, Florida. Total mercury in runoff consisted of 58% particulate and 42% filtered forms. Concentration comparisons at the start and end of runoff events indicate that about 85% of particulate total mercury and 93% of particulate methylmercury were removed from the surface before runoff ended. Filtered mercury concentrations showed less than 50% reduction of both total and methylmercury from first flush to final flush. Direct comparison between rainfall and runoff at this urban site indicates dry deposition accounted for 22% of total inorganic mercury in runoff. ?? 2007 Springer Science+Business Media B.V.

Water resources

NASA Technical Reports Server (NTRS)

Salomonson, V. V.; Rango, A.

1973-01-01

The application of ERTS-1 imagery to the conservation and control of water resources is discussed. The effects of exisiting geology and land use in the water shed area on the hydrologic cycle and the general characteristics of runoff are described. The effects of floods, snowcover, and glaciers are analyzed. The use of ERTS-1 imagery to map surface water and wetland areas to provide rapid inventorying over large regions of water bodies is reported.

Rapid response tools and datasets for post-fire modeling: Linking Earth Observations and process-based hydrological models to support post-fire remediation

Treesearch

M. E. Miller; M. Billmire; W. J. Elliot; K. A. Endsley; P. R. Robichaud

2015-01-01

Preparation is key to utilizing Earth Observations and process-based models to support post-wildfire mitigation. Post-fire flooding and erosion can pose a serious threat to life, property and municipal water supplies. Increased runoff and sediment delivery due to the loss of surface cover and fire-induced changes in soil properties are of great concern. Remediation...

Changes in baseflow conditions over a 42 year observation period for the Little River Experimental Watershed in South Georgia

Treesearch

David D. Bosch; Randall G. Williams; Timothy C. Strickland; Jeff G. Arnold; Peter G. Allen

2016-01-01

Hydrology is the driving force of sediment, nutrient, and pesticide movement. Separation of streamflow hydrographs into rapid surface runoff and baseflow can vastly improve our understanding of chemical transport. In addition, characterizing these two components of streamflow can also greatly improve overall watershed hydrologic budgets which are critical for accurate...

Assessment of surface runoff depth changes in S\\varǎţel River basin, Romania using GIS techniques

NASA Astrophysics Data System (ADS)

Romulus, Costache; Iulia, Fontanine; Ema, Corodescu

2014-09-01

S\\varǎţel River basin, which is located in Curvature Subcarpahian area, has been facing an obvious increase in frequency of hydrological risk phenomena, associated with torrential events, during the last years. This trend is highly related to the increase in frequency of the extreme climatic phenomena and to the land use changes. The present study is aimed to highlight the spatial and quantitative changes occurred in surface runoff depth in S\\varǎţel catchment, between 1990-2006. This purpose was reached by estimating the surface runoff depth assignable to the average annual rainfall, by means of SCS-CN method, which was integrated into the GIS environment through the ArcCN-Runoff extension, for ArcGIS 10.1. In order to compute the surface runoff depth, by CN method, the land cover and the hydrological soil classes were introduced as vector (polygon data), while the curve number and the average annual rainfall were introduced as tables. After spatially modeling the surface runoff depth for the two years, the 1990 raster dataset was subtracted from the 2006 raster dataset, in order to highlight the changes in surface runoff depth.

Mechanism of the surface runoff generation processes of a permafrost watershed in the Qinghai-Tibet plateau

NASA Astrophysics Data System (ADS)

Genxu, W.

2017-12-01

There is a lack of knowledge about how to quantify runoff generation and the hydrological processes operating in permafrost catchments on permafrost-dominant catchments. To understand the mechanism of runoff generation processes in permafrost catchments, a typical headwater catchment with continuous permafrost on the Tibetan Plateau was measured. A new approach is presented in this study to account for runoff processes on the spring thawing period and autumn freezing period, when runoff generation clearly differs from that of non-permafrost catchments. This approach introduces a soil temperature-based water saturation function and modifies the soil water storage curve with a soil temperature threshold. The results show that surface soil thawing induced saturation excess runoff and subsurface interflow account for approximately 66-86% and 14-34% of total spring runoff, respectively, and the soil temperature significantly affects the runoff generation pattern, the runoff composition and the runoff coefficient with the enlargement of the active layer. The suprapermafrost groundwater discharge decreases exponentially with active layer frozen processes during autumn runoff recession, whereas the ratio of groundwater discharge to total runoff and the direct surface runoff coefficient simultaneously increase. The bidirectional freezing of the active layer controls and changes the autumn runoff processes and runoff composition. The new approach could be used to further develop hydrological models of cold regions dominated by permafrost.

A study of the effect of controlled drainage on surface runoff

USDA-ARS?s Scientific Manuscript database

There is uncertainty about the impact of drainage water management (DWM) on surface runoff, and concern that DWM may increase runoff. To examine this concern, water was applied by sprinkler irrigation to 8 plots which were individually equipped with instrumentation to measure both surface and subsur...

Impact of land-use on water pollution in a rapidly urbanizing catchment in China

NASA Astrophysics Data System (ADS)

Khu, Soon-Thiam; Qin, Huapeng

2010-05-01

Many catchments in developing countries are undergoing fast urbanization which is usually characterized by population increase, economic growth as well as drastic changes of land-use from natural/rural to urban area. During the urbanization process, some catchments experience water quality deterioration due to rapid increase of pollution loads. Nonpoint source pollution resulting from storm water runoff has been recognized as one of the major causes of pollutants in many cities in developing countries. The composition of land-use for a rapidly urbanizing catchment is usually heterogeneous, and this may result in significant spatial variations of storm runoff pollution and increase the difficulties of water quality management in the catchment. The Shiyan Reservoir catchment, a typical rapidly urbanizing area in China, is chosen as the study area, and temporary monitoring sites were set at the outlets of its 6 sub-catchments to synchronously measured rainfall, runoff and water quality during 4 storm events. Three indicators, event pollutant loads per unit area (EPL), event mean concentration (EMC) and pollutant loads transported by the first 50% of runoff volume (FF50), were used to describe the runoff pollution for different pollutants (such as COD, BOD, NH3-N, TN, TP and SS) in each sub-catchment during the storm events; and the correlations between runoff pollution spatial variations and land-use patterns were tested by Spearman's rank correlation analysis. The results indicated that similar spatial variation trends were found for different pollutants (EPL or EMC) in light storm events, which strongly correlate with the proportion of residential land-use; however, they have different trends in heavy storm events, which correlate with the different proportional combination of residential, industrial, agricultural and bare land-use. It is also shown that it is necessary to consider some pervious land-use types in runoff pollution monitoring or management for a rapidly urbanizing area, particularly in heavy storm.

Land cover effects on thresholds for surface runoff generation in Eastern Madagascar

NASA Astrophysics Data System (ADS)

van Meerveld, Ilja H. J.; Prasad Ghimire, Chandra; Zwartendijk, Bob W.; Ravelona, Maafaka; Lahitiana, Jaona; Bruijnzeel, L. Adrian

2016-04-01

Reforestation and natural regrowth in the tropics are promoted for a wide range of benefits, including carbon sequestration, land rehabilitation and streamflow regulation. However, their effects on runoff generation mechanisms and streamflow are still poorly understood. Evaporative losses (transpiration and interception) likely increase with forest regrowth, while infiltration rates are expected to increase and surface runoff occurrence is, therefore, expected to decrease. As part of a larger project investigating the effects of land use on hydrological processes in upland Eastern Madagascar, this presentation reports on a comparison of the thresholds for surface runoff generation at a degraded grassland site, a young secondary forest site (5-7 years; LAI 1.83) and a mature secondary forest site (ca. 20 years; LAI 3.39). Surface runoff was measured on two (young and mature secondary forest) or three (degraded site) 3 m by 10 m plots over a one-year period (October 2014-September 2015). Soil moisture was measured at four (degraded site) to six depths (both forests), while perched groundwater levels were measured in piezometers installed at 30 cm below the soil surface. Soil hydraulic conductivity was measured in situ at the surface and at 10-20 and 20-30 cm depths at three locations in each plot. Porosity, moisture content at field capacity and bulk density were determined from soil cores taken at 2.5-7.5, 12.5-17.5 and 22.5-27.5 cm depth. The porosity and texture of the different plots were comparable. The hydraulic conductivity of the soil differed between the different land uses and declined sharply at 20-30 cm below the soil surface. Total surface runoff during the study period was 11% of incident rainfall at the degraded site vs. 2% for the two secondary forest sites. Maximum monthly runoff coefficients were 22%, 3.5% and 2.7% for the degraded site, the young forest site and the mature forest site, respectively, but individual event runoff coefficients could be as high as 45%, 12%, and 10%, respectively. Initial analyses indicate that a threshold rainfall amount was required before surface runoff occurs. Comparison of surface runoff occurrence with perched groundwater levels and soil moisture data showed that surface runoff was generated once the top-soil (0-20 cm) became saturated because of impeded drainage to the low hydraulic conductivity deeper layers. Thresholds for saturation overland flow generation were higher at the two forested sites compared to the degraded grassland due to their greater percolation to deeper layers, faster shallow lateral flow, and larger available storage in the top layers. The detailed analyses of the soil moisture and rainfall thresholds for surface runoff generation and their temporal variation will be used to develop a bucket-based conceptual model for runoff generation at these upland tropical sites. Key words: Runoff plot, rainfall threshold, soil moisture, saturation overland flow, secondary forest, soil hydraulic conductivity, Madagascar, p4ges project

Modeling urban storm rainfall runoff from diverse underlying surfaces and application for control design in Beijing.

PubMed

Ouyang, Wei; Guo, Bobo; Hao, Fanghua; Huang, Haobo; Li, Junqi; Gong, Yongwei

2012-12-30

Managing storm rainfall runoff is paramount in semi-arid regions with urban development. In Beijing, pollution prevention in urban storm runoff and storm water utilization has been identified as the primary strategy for urban water management. In this paper, we sampled runoff during storm rainfall events and analyzed the concentration of chemical oxygen demand (COD), total suspended solids (TSS) and total phosphorus (TP) in the runoff. Furthermore, the first flush effect of storm rainfall from diverse underlying surfaces was also analyzed. With the Storm Water Management Model (SWMM), the different impervious rates of underlying surfaces during the storm runoff process were expressed. The removal rates of three typical pollutants and their interactions with precipitation and underlying surfaces were identified. From these rates, the scenarios regarding the urban storm runoff pollution loading from different designs of underlying previous rates were assessed with the SWMM. First flush effect analysis showed that the first 20% of the storm runoff should be discarded, which can help in utilizing the storm water resource. The results of this study suggest that the SWMM can express in detail the storm water pollution patterns from diverse underlying surfaces in Beijing, which significantly affected water quality. The scenario analysis demonstrated that impervious rate adjustment has the potential to reduce runoff peak and decrease pollution loading. Copyright © 2012 Elsevier Ltd. All rights reserved.

Using Rapid Indicators for Enterococcus to assess the Risk of Illness after Exposure to Urban Runoff Contaminated Marine Water

EPA Science Inventory

BACKGROUND: Traditional fecal indicator bacteria (FIB) measurement is too slow (>18 h) for timely swimmer warnings. OBJECTIVES: Assess relationship of rapid indicator methods (qPCR) to illness at a marine beach impacted by urban runoff. METHODS: We measured baseline and two...

Nonlinear and threshold-dominated runoff generation controls DOC export in a small peat catchment

NASA Astrophysics Data System (ADS)

Birkel, C.; Broder, T.; Biester, H.

2017-03-01

We used a relatively simple two-layer, coupled hydrology-biogeochemistry model to simultaneously simulate streamflow and stream dissolved organic carbon (DOC) concentrations in a small lead and arsenic contaminated upland peat catchment in northwestern Germany. The model procedure was informed by an initial data mining analysis, in combination with regression relationships of discharge, DOC, and element export. We assessed the internal model DOC processing based on stream DOC hysteresis patterns and 3-hourly time step groundwater level and soil DOC data for two consecutive summer periods in 2013 and 2014. The parsimonious model (i.e., few calibrated parameters) showed the importance of nonlinear and rapid near-surface runoff generation mechanisms that caused around 60% of simulated DOC load. The total load was high even though these pathways were only activated during storm events on average 30% of the monitoring time—as also shown by the experimental data. Overall, the drier period 2013 resulted in increased nonlinearity but exported less DOC (115 kg C ha-1 yr-1 ± 11 kg C ha-1 yr-1) compared to the equivalent but wetter period in 2014 (189 kg C ha-1 yr-1 ± 38 kg C ha-1 yr-1). The exceedance of a critical water table threshold (-10 cm) triggered a rapid near-surface runoff response with associated higher DOC transport connecting all available DOC pools and subsequent dilution. We conclude that the combination of detailed experimental work with relatively simple, coupled hydrology-biogeochemistry models not only allowed the model to be internally constrained but also provided important insight into how DOC and tightly coupled pollutants or trace elements are mobilized.

Rapid fluvial incision of a late Holocene lava flow: Insights from LiDAR, alluvial stratigraphy, and numerical modeling

USGS Publications Warehouse

Sweeney, Kristin; Roering, Joshua J.

2016-01-01

Volcanic eruptions fundamentally alter landscapes, paving over channels, decimating biota, and emplacing fresh, unweathered material. The fluvial incision of blocky lava flows is a geomorphic puzzle. First, high surface permeability and lack of sediment should preclude geomorphically effective surface runoff and dissection. Furthermore, past work has demonstrated the importance of extreme floods in driving incision via column toppling and plucking in columnar basalt, but it is unclear how incision occurs in systems where surface blocks are readily mobile. We examine rapid fluvial incision of the Collier lava flow, an andesitic Holocene lava flow in the High Cascades of Oregon. Since lava flow emplacement ∼1600 yr ago, White Branch Creek has incised bedrock gorges up to 8 m deep into the coherent core of the lava flow and deposited >0.2 km3 of sediment on the lava flow surface. Field observation points to a bimodal discharge regime in the channel, with evidence for both annual snowmelt runoff and outburst floods from Collier glacier, as well as historical evidence of vigorous glacial meltwater. To determine the range of discharge events capable of incision in White Branch Creek, we used a mechanistic model of fluvial abrasion. We show that the observed incision implies that moderate flows are capable of both initiating channel formation and sustaining incision. Our results have implications for the evolution of volcanic systems worldwide, where glaciation and/or mass wasting may accelerate fluvial processes by providing large amounts of sediment to otherwise porous, sediment-starved landscapes.

Ground-water sapping processes, Western Desert, Egypt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, W.; Arvidson, R.E.; Sultan, M.

1997-01-01

Depressions of the Western Desert of Egypt (specifically, Kharga, Farafra, and Kurkur regions) are mainly occupied by shales that are impermeable, but easily erodible by rainfall and runoff, whereas the surrounding plateaus are composed of limestones that are permeable and more resistant to fluvial erosion under semiarid to arid conditions. A computer simulation model was developed to quantify the ground-water sapping processes, using a cellular automata algorithm with coupled surface runoff and ground-water flow for a permeable, resistant layer over an impermeable, friable unit. Erosion, deposition, slumping, and generation of spring-derived tufas were parametrically modeled. Simulations using geologically reasonable parametersmore » demonstrate that relatively rapid erosion of the shales by surface runoff, ground-water sapping, and slumping of the limestones, and detailed control by hydraulic conductivity inhomogeneities associated with structures explain the depressions, escarpments, and associated landforms and deposits. Using episodic wet pulses, keyed by {delta}{sup 18}O deep-sea core record, the model produced tufa ages that are statistically consistent with the observed U/Th tufa ages. This result supports the hypothesis that northeastern African wet periods occurred during interglacial maxima. This {delta}{sup 18}O-forced model also replicates the decrease in fluvial and sapping activity over the past million years. 65 refs., 21 figs., 2 tabs.« less

Model-based calculations of surface mass balance of mountain glaciers for the purpose of water consumption planning: focus on Djankuat Glacier (Central Caucasus)

NASA Astrophysics Data System (ADS)

Rybak, O. O.; Rybak, E. A.

2018-01-01

Mountain glaciers act as regulators of run-off in the summer period, which is very crucial for economy especially in dynamically developing regions with rapidly growing population, such as Central Asia or the Northern Caucasus in Russia. In overall, glaciers stabilize water consumption in comparatively arid areas and provide conditions for sustainable development of the economy in mountainous regions and in the surrounding territories. A proper prediction of the glacial run-off is required to elaborate strategies of the regional development. This goal can be achieved by implementation of mathematical modeling methods into planning methodologies. In the paper, we consider one of the first steps in glacier dynamical modeling - surface mass balance simulation. We focus on the Djankuat Glacier in the Central Caucasus, where regular observations have been conducted during the last fifty years providing an exceptional opportunity to calibrate and to validate a mathematical model.

Modeling phosphorus losses from soils amended with cattle manure and chemical fertilizers

USDA-ARS?s Scientific Manuscript database

While applied manure/fertilizer is an important source of P loss in surface runoff, few models simulate the direct transfer of phosphorus (P) from soil-surface-applied manure/fertilizer to runoff. The SurPhos model was tested with 2008-2010 growing season, daily surface runoff data from clay loam ex...

Exploiting Soil Moisture, Precipitation, and Streamflow Observations to Evaluate Soil Moisture/Runoff Coupling in Land Surface Models

NASA Astrophysics Data System (ADS)

Crow, W. T.; Chen, F.; Reichle, R. H.; Xia, Y.; Liu, Q.

2018-05-01

Accurate partitioning of precipitation into infiltration and runoff is a fundamental objective of land surface models tasked with characterizing the surface water and energy balance. Temporal variability in this partitioning is due, in part, to changes in prestorm soil moisture, which determine soil infiltration capacity and unsaturated storage. Utilizing the National Aeronautics and Space Administration Soil Moisture Active Passive Level-4 soil moisture product in combination with streamflow and precipitation observations, we demonstrate that land surface models (LSMs) generally underestimate the strength of the positive rank correlation between prestorm soil moisture and event runoff coefficients (i.e., the fraction of rainfall accumulation volume converted into stormflow runoff during a storm event). Underestimation is largest for LSMs employing an infiltration-excess approach for stormflow runoff generation. More accurate coupling strength is found in LSMs that explicitly represent subsurface stormflow or saturation-excess runoff generation processes.

[Research on evaluation of water quality of Beijing urban stormwater runoff].

PubMed

Hou, Pei-Qiang; Ren, Yu-Fen; Wang, Xiao-Ke; Ouyang, Zhi-Yun; Zhou, Xiao-Ping

2012-01-01

The natural rainwater and stormwater runoff samples from three underlying surfaces (rooftop, campus road and ring road) were sampled and analyzed from July to October, 2010 in Beijing. Eight rainfall events were collected totally and thirteen water quality parameters were measured in each event. Grey relationship analysis and principal component analysis were applied to assess composite water quality and identify the main pollution sources of stormwater runoff. The results show that the composite water quality of ring road runoff is mostly polluted, and then is rooftop runoff, campus road runoff and rainwater, respectively. The composite water quality of ring road runoff is inferior to V class of surface water, while rooftop runoff, campus road runoff and rainwater are in II class of surface water. The mean concentration of TN and NH4(+)-N in rainwater and runoff is 5.49-11.75 mg x L(-1) and 2.90-5.67 mg x L(-1), respectively, indicating that rainwater and runoff are polluted by nitrogen (N). Two potential pollution sources are identified in ring road runoff: (1) P, SS and organic pollutant are possibly related to debris which is from vehicle tyre and material of ring road; (2) N and dissolved metal have relations with automobile exhaust emissions and bulk deposition.

Joint variability of global runoff and global sea surface temperatures

USGS Publications Warehouse

McCabe, G.J.; Wolock, D.M.

2008-01-01

Global land surface runoff and sea surface temperatures (SST) are analyzed to identify the primary modes of variability of these hydroclimatic data for the period 1905-2002. A monthly water-balance model first is used with global monthly temperature and precipitation data to compute time series of annual gridded runoff for the analysis period. The annual runoff time series data are combined with gridded annual sea surface temperature data, and the combined dataset is subjected to a principal components analysis (PCA) to identify the primary modes of variability. The first three components from the PCA explain 29% of the total variability in the combined runoff/SST dataset. The first component explains 15% of the total variance and primarily represents long-term trends in the data. The long-term trends in SSTs are evident as warming in all of the oceans. The associated long-term trends in runoff suggest increasing flows for parts of North America, South America, Eurasia, and Australia; decreasing runoff is most notable in western Africa. The second principal component explains 9% of the total variance and reflects variability of the El Ni??o-Southern Oscillation (ENSO) and its associated influence on global annual runoff patterns. The third component explains 5% of the total variance and indicates a response of global annual runoff to variability in North Aflantic SSTs. The association between runoff and North Atlantic SSTs may explain an apparent steplike change in runoff that occurred around 1970 for a number of continental regions.

Precipitation Phase Partitioning during Inland Penetrating Atmospheric River events: Role of Initial Land Surface Conditions

NASA Astrophysics Data System (ADS)

Rudisill, W. J.; Flores, A. N.; FitzGerald, K.; Masarik, M. T.

2017-12-01

In the Western US, the occurrence (or lack thereof) of a handful of cool-season Atmospheric River (AR) events exerts significant controls on the seasonal water budget in many watersheds. The occurrence of these ARs can serve to alleviate drought and can also lead to significant flooding. In winter seasons, ARs typically bring warmer than average conditions and both rain and snow. To date, there has been little effort to understand how the land surface hydrological states prior to and during the arrival of ARs, acting on the surface water and energy balance, impact the onset, extent, and evolution of precipitation intensity and phase during AR events. While precipitation arriving as snow can contribute to seasonal snowpacks that lead to runoff later in hot/dry seasons, liquid precipitation can contribute to more rapid runoff or deplete existing snowpacks. The latter case, in which latent and advected heat from fallen rain causes snowmelt, is a key mechanism of flood and landslide-producing runoff in the Western United States. Motivated by an extensive, flood producing AR in 2010, we examine the sensitivity of hydrometeor phase to land surface forcings (sensible/latent heating, short/longwave radiation) using the WRF (Weather Research and Forecasting) model in Central Idaho. Specifically, we evaluate whether pre-existing snow covered area extent, snow water equivalent (SWE), and cold-content influence the partitioning of precipitation into solid and liquid phases during inland AR events. Our experimental design leverages a long-term coupled land-atmosphere simulation with WRF over the study domain in order to evaluate how a set of particular AR events evolve when exposed to initial land surface states capturing a broad range of climatological conditions during the past 30 years.

Runoff of pyrethroid insecticides from concrete surfaces following simulated and natural rainfalls.

PubMed

Jiang, Weiying; Haver, Darren; Rust, Michael; Gan, Jay

2012-03-01

Intensive residential use of insecticides has resulted in their ubiquitous presence as contaminants in urban surface streams. For pest eradication, urban hard surfaces such as concrete are often directly treated with pesticides, and wind/water can also carry pesticides onto hard surfaces from surrounding areas. This study expanded on previous bench-scale studies by considering pesticide runoff caused by irrigation under dry weather conditions and rain during the wet season, and evaluated the effects of pesticide residence time on concrete, single versus recurring precipitations, precipitation intensity, and concrete surface conditions, on pesticide transferability to runoff water. Runoff from concrete 1 d after pesticide treatment contained high levels of bifenthrin (82 μg/L) and permethrin (5143 μg/L for cis and 5518 μg/L for trans), indicating the importance of preventing water contact on concrete after pesticide treatments. Although the runoff transferability quickly decreased as the pesticide residence time on concrete increased, detectable residues were still found in runoff water after 3 months (89 d) exposure to hot and dry summer conditions. ANOVA analysis showed that precipitation intensities and concrete surface conditions (i.e., acid wash, silicone seal, stamping, and addition of microsilica) did not significantly affect the pesticide transferability to runoff. For concrete slabs subjected to natural rainfalls during the winter wet season, pesticide levels in the runoff decreased as the time interval between pesticide application and the rain event increased. However, bifenthrin and permethrin were still detected at 0.15-0.17 and 0.75-1.15 μg/L in the rain runoff after 7 months (221 d) from the initial treatment. In addition, pesticide concentrations showed no decrease between the two rainfall events, suggesting that concrete surfaces contaminated by pesticides may act as a reservoir for pesticide residues, leading to sustained urban runoff contamination. Copyright © 2011 Elsevier Ltd. All rights reserved.

Natural flood risk management in flashy headwater catchments: managing runoff peaks, timing, water quality and sediment regimes

NASA Astrophysics Data System (ADS)

Wilkinson, Mark; Addy, Steve; Ghimire, Sohan; Kenyon, Wendy; Nicholson, Alex; Quinn, Paul; Stutter, Marc; Watson, Helen

2013-04-01

Over the past decade many European catchments have experienced an unusually high number of flood events. A large number of these events are the result of intense rainfall in small headwater catchments which are dominated by surface runoff generation, resulting in flash flooding of local communities. Soil erosion and related water quality issues, among others, are typically associated with such rapid runoff generation. The hazard of flooding is increasing owing to impacts of changing climatic patterns (including more intense summer storms), intensification of agriculture within rural catchments and continued pressure to build on floodplains. Concurrently, the cost of constructing and maintaining traditional flood defences in small communities outweigh the potential benefits. Hence, there is a growing interest in more cost effective natural approaches that also have multipurpose benefits in terms of sediment, water quality, and habitat creation. Many catchments in Europe are intensively farmed and there is great potential for agriculture to be part of the solution to flood risk management. Natural flood management (NFM) is the alteration, restoration or use of landscape features with the aim of reducing flood risk by slowing down, storing (and filtering) rapid surface runoff. NFM includes measures such as temporarily storing water in ponds/wetlands, increasing soil infiltration, planting trees on floodplains and within catchments, re-meandering and wood placements in streams/ditches. In this presentation we highlight case studies from densely instrumented research sites across the UK (which could be typical of many European catchments) where NFM measures have been installed in small scale flashy catchments. The presentation will give an overview of the function of these measures in these catchments and how other multiple benefits are being accrued. Study catchments include the headwater catchments of the Bowmont (3 to 8 km2) and Belford Burn (6 km2) catchments. These catchments are known for their rapid runoff generation and have downstream local communities at risk of flash flooding. In Bowmont, NFM measures are currently being put in place to restore river bars and to store water more effectively on the flood plains during these flashy events. For example, Apex engineered wood structure in the river channel and riparian zones are designed to trap sediment and log bank protection structures are being installed to stop bank erosion. Tree planting in the catchment is also taking place. In the Belford catchment storage ponds and woody debris have been installed over the past five years to help to reduce the flood risk to the village of Belford. A dense instrumentation network has provided data for analysis and modelling which shows evidence of local scale flood peak reductions along with the collection of large amounts of sediment. A modelling study carried out (using a pond network model) during an intense summer storm showed that 30 small scale pond features used in sequence could reduce the flood peak by ~35% at the local scale. Findings show that managing surface runoff and local ditch flow at local scale headwater catchments is a cost effective way of managing flashy catchment for flood risk and sediment control. Working with catchment stakeholders is vital. Information given by the local community post flooding has been useful in placing NFM measures throughout the catchments. Involving the local communities in these projects and giving them access to the data and model outputs has helped to develop these projects further.

High frequency monitoring of pesticides in runoff water to improve understanding of their transport and environmental impacts.

PubMed

Lefrancq, Marie; Jadas-Hécart, Alain; La Jeunesse, Isabelle; Landry, David; Payraudeau, Sylvain

2017-06-01

Rainfall-induced peaks in pesticide concentrations can occur rapidly. Low frequency sampling may therefore largely underestimate maximum pesticide concentrations and fluxes. Detailed storm-based sampling of pesticide concentrations in runoff water to better predict pesticide sources, transport pathways and toxicity within the headwater catchments is lacking. High frequency monitoring (2min) of seven pesticides (Dimetomorph, Fluopicolide, Glyphosate, Iprovalicarb, Tebuconazole, Tetraconazole and Triadimenol) and one degradation product (AMPA) were assessed for 20 runoff events from 2009 to 2012 at the outlet of a vineyard catchment in the Layon catchment in France. The maximum pesticide concentrations were 387μgL -1 . Samples from all of the runoff events exceeded the legal limit of 0.1μgL -1 for at least one pesticide (European directive 2013/39/EC). High resolution sampling used to detect the peak pesticide levels revealed that Toxic Units (TU) for algae, invertebrates and fish often exceeded the European Uniform principles (25%). The point and average (time or discharge-weighted) concentrations indicated up to a 30- or 4-fold underestimation of the TU obtained when measuring the maximum concentrations, respectively. This highlights the important role of sampling methods for assessing peak exposure. High resolution sampling combined with concentration-discharge hysteresis analyses revealed that clockwise responses were predominant (52%), indicating that Hortonian runoff is the prevailing surface runoff trigger mechanism in the study catchment. The hysteresis patterns for suspended solids and pesticides were highly dynamic and storm- and chemical-dependent. Intense rainfall events induced stronger C-Q hysteresis (magnitude). This study provides new insights into the complexity of pesticide dynamics in runoff water and highlights the ability of hysteresis analysis to improve understanding of pesticide supply and transport. Copyright © 2017 Elsevier B.V. All rights reserved.

High frequency monitoring of pesticides in runoff water from a vineyard: ecotoxicological and hysteresis pattern analysis

NASA Astrophysics Data System (ADS)

Lefrancq, Marie; Jadas-Hécart, Alain; La Jeunesse, Isabelle; Landry, David; Payraudeau, Sylvain

2017-04-01

Rainfall-induced peaks in pesticide concentrations can occur rapidly; therefore, low frequency sampling may largely underestimate maximum pesticide concentrations and fluxes. Detailed storm-based sampling of pesticide concentrations in runoff water to better predict pesticide sources, transport pathways and toxicity within the headwater catchments is actually lacking. High frequency monitoring (2 min) of dissolved concentrations and loads for seven pesticides (Dimetomorph, Fluopicolide, Glyphosate, Iprovalicarb, Tebuconazole, Tetraconazole and Triadimenol) and one degradation product (AMPA) were assessed for 20 runoff events from 2009 to 2012 at the outlet of a vineyard catchment in the Layon catchment in France. The pesticide concentrations reached 387 µg/L. All of the runoff events exceeded the mandated acceptable concentrations of 0.1 µg/L for each pesticide (European directive 2013/39/EC). High resolution sampling used to detect the peak pesticide levels revealed that Toxic Units (TU) for algae, invertebrates and fish often exceeded the European Uniform principles (25%). The instantaneous and average (time or discharge-weighted) concentrations indicated an up to 30- or 4-fold underestimation of the TU obtained when measuring the maximum concentrations, respectively, highlighting the important role of the sampling methods for assessing peak exposure. High resolution sampling combined with concentration-discharge hysteresis analyses revealed that clockwise responses were predominant (52%), indicating that Hortonian runoff is the prevailing surface runoff trigger mechanism in the study catchment. The hysteresis patterns for suspended solids and pesticides were highly dynamic and storm- and chemical-dependent. Intense rainfall events induced stronger C-Q hysteresis (magnitude). This study provides new insights into the complexity of pesticide dynamics in runoff water and highlights the ability of hysteresis analysis to improve the understanding of pesticide supply and transport.

[Characteristics of soil phosphorus runoff under different rainfall intensities in the typical vegetable plot of Taihu Basin].

PubMed

Yang, Li-Xia; Yang, Gui-Shan; Yuan, Shao-Feng; Wu, Ye

2007-08-01

Experiments of field runoff plots, which were conducted at vegetable plots in Hongsheng town of Wuxi city--the typical region of Taihu Basin, were designed to assess the effects of different rainfall intensities on soil phosphorus runoff loss from vegetable plots by artificial rainfall simulations. Results showed that there was a relationship of power function between initial runoff-generation time and rainfall intensity. Runoff amount slowly increased under small rainfall intensity, but rapidly increased with rainfall intensity increase. The concentrations of total phosphorus (TP) and particulate phosphorus (PP) were higher at the early stage, then gradually decreased with time and finally reached a comparative steady stage under 0.83, 1.17 and 1.67 mm x min(-1). However they indicated no obvious trend except wavy undulation under 2.50 mm x min(-1). In the course of rainfall-runoff, dissolved phosphorus (DP) gently varied and accounted for 20% - 32% of TP. PP was 68% - 80% of TP and its change trend was consistent with TP. Therefore, PP was main loss form of soil phosphorus runoff. Comparison of different phosphorous loss rate under different rainfall intensities suggested that loss rate of TP and DP under 2.50 mm x min(-1) was 20 times and 33 times higher than that under 0.83 mm x min(-1), which showed that loss rate of PP and DP increased with the increase of rainfall intensities. Results indicated that lots of inorganic dissolved phosphorus (DIP) of phosphorous fertilizer was discharged into water environment by using fertilizer in soil surface before rainfall, which increased loss of DP and greatly aggravated degree of water eutrophication.

Direct measurements of meltwater runoff on the Greenland ice sheet surface

NASA Astrophysics Data System (ADS)

Smith, Laurence C.; Yang, Kang; Pitcher, Lincoln H.; Overstreet, Brandon T.; Chu, Vena W.; Rennermalm, Åsa K.; Ryan, Jonathan C.; Cooper, Matthew G.; Gleason, Colin J.; Tedesco, Marco; Jeyaratnam, Jeyavinoth; van As, Dirk; van den Broeke, Michiel R.; van de Berg, Willem Jan; Noël, Brice; Langen, Peter L.; Cullather, Richard I.; Zhao, Bin; Willis, Michael J.; Hubbard, Alun; Box, Jason E.; Jenner, Brittany A.; Behar, Alberto E.

2017-12-01

Meltwater runoff from the Greenland ice sheet surface influences surface mass balance (SMB), ice dynamics, and global sea level rise, but is estimated with climate models and thus difficult to validate. We present a way to measure ice surface runoff directly, from hourly in situ supraglacial river discharge measurements and simultaneous high-resolution satellite/drone remote sensing of upstream fluvial catchment area. A first 72-h trial for a 63.1-km2 moulin-terminating internally drained catchment (IDC) on Greenland's midelevation (1,207–1,381 m above sea level) ablation zone is compared with melt and runoff simulations from HIRHAM5, MAR3.6, RACMO2.3, MERRA-2, and SEB climate/SMB models. Current models cannot reproduce peak discharges or timing of runoff entering moulins but are improved using synthetic unit hydrograph (SUH) theory. Retroactive SUH applications to two older field studies reproduce their findings, signifying that remotely sensed IDC area, shape, and supraglacial river length are useful for predicting delays in peak runoff delivery to moulins. Applying SUH to HIRHAM5, MAR3.6, and RACMO2.3 gridded melt products for 799 surrounding IDCs suggests their terminal moulins receive lower peak discharges, less diurnal variability, and asynchronous runoff timing relative to climate/SMB model output alone. Conversely, large IDCs produce high moulin discharges, even at high elevations where melt rates are low. During this particular field experiment, models overestimated runoff by +21 to +58%, linked to overestimated surface ablation and possible meltwater retention in bare, porous, low-density ice. Direct measurements of ice surface runoff will improve climate/SMB models, and incorporating remotely sensed IDCs will aid coupling of SMB with ice dynamics and subglacial systems.

Direct measurements of meltwater runoff on the Greenland ice sheet surface.

PubMed

Smith, Laurence C; Yang, Kang; Pitcher, Lincoln H; Overstreet, Brandon T; Chu, Vena W; Rennermalm, Åsa K; Ryan, Jonathan C; Cooper, Matthew G; Gleason, Colin J; Tedesco, Marco; Jeyaratnam, Jeyavinoth; van As, Dirk; van den Broeke, Michiel R; van de Berg, Willem Jan; Noël, Brice; Langen, Peter L; Cullather, Richard I; Zhao, Bin; Willis, Michael J; Hubbard, Alun; Box, Jason E; Jenner, Brittany A; Behar, Alberto E

2017-12-12

Meltwater runoff from the Greenland ice sheet surface influences surface mass balance (SMB), ice dynamics, and global sea level rise, but is estimated with climate models and thus difficult to validate. We present a way to measure ice surface runoff directly, from hourly in situ supraglacial river discharge measurements and simultaneous high-resolution satellite/drone remote sensing of upstream fluvial catchment area. A first 72-h trial for a 63.1-km 2 moulin-terminating internally drained catchment (IDC) on Greenland's midelevation (1,207-1,381 m above sea level) ablation zone is compared with melt and runoff simulations from HIRHAM5, MAR3.6, RACMO2.3, MERRA-2, and SEB climate/SMB models. Current models cannot reproduce peak discharges or timing of runoff entering moulins but are improved using synthetic unit hydrograph (SUH) theory. Retroactive SUH applications to two older field studies reproduce their findings, signifying that remotely sensed IDC area, shape, and supraglacial river length are useful for predicting delays in peak runoff delivery to moulins. Applying SUH to HIRHAM5, MAR3.6, and RACMO2.3 gridded melt products for 799 surrounding IDCs suggests their terminal moulins receive lower peak discharges, less diurnal variability, and asynchronous runoff timing relative to climate/SMB model output alone. Conversely, large IDCs produce high moulin discharges, even at high elevations where melt rates are low. During this particular field experiment, models overestimated runoff by +21 to +58%, linked to overestimated surface ablation and possible meltwater retention in bare, porous, low-density ice. Direct measurements of ice surface runoff will improve climate/SMB models, and incorporating remotely sensed IDCs will aid coupling of SMB with ice dynamics and subglacial systems. Copyright © 2017 the Author(s). Published by PNAS.

Direct measurements of meltwater runoff on the Greenland ice sheet surface

PubMed Central

Smith, Laurence C.; Yang, Kang; Pitcher, Lincoln H; Overstreet, Brandon T.; Chu, Vena W.; Rennermalm, Åsa K.; Ryan, Jonathan C.; Cooper, Matthew G.; Gleason, Colin J.; Tedesco, Marco; Jeyaratnam, Jeyavinoth; van As, Dirk; van den Broeke, Michiel R.; van de Berg, Willem Jan; Noël, Brice; Langen, Peter L.; Cullather, Richard I.; Zhao, Bin; Hubbard, Alun; Box, Jason E.; Jenner, Brittany A.; Behar, Alberto E.

2017-01-01

Meltwater runoff from the Greenland ice sheet surface influences surface mass balance (SMB), ice dynamics, and global sea level rise, but is estimated with climate models and thus difficult to validate. We present a way to measure ice surface runoff directly, from hourly in situ supraglacial river discharge measurements and simultaneous high-resolution satellite/drone remote sensing of upstream fluvial catchment area. A first 72-h trial for a 63.1-km2 moulin-terminating internally drained catchment (IDC) on Greenland’s midelevation (1,207–1,381 m above sea level) ablation zone is compared with melt and runoff simulations from HIRHAM5, MAR3.6, RACMO2.3, MERRA-2, and SEB climate/SMB models. Current models cannot reproduce peak discharges or timing of runoff entering moulins but are improved using synthetic unit hydrograph (SUH) theory. Retroactive SUH applications to two older field studies reproduce their findings, signifying that remotely sensed IDC area, shape, and supraglacial river length are useful for predicting delays in peak runoff delivery to moulins. Applying SUH to HIRHAM5, MAR3.6, and RACMO2.3 gridded melt products for 799 surrounding IDCs suggests their terminal moulins receive lower peak discharges, less diurnal variability, and asynchronous runoff timing relative to climate/SMB model output alone. Conversely, large IDCs produce high moulin discharges, even at high elevations where melt rates are low. During this particular field experiment, models overestimated runoff by +21 to +58%, linked to overestimated surface ablation and possible meltwater retention in bare, porous, low-density ice. Direct measurements of ice surface runoff will improve climate/SMB models, and incorporating remotely sensed IDCs will aid coupling of SMB with ice dynamics and subglacial systems. PMID:29208716

Runoff phosphorus losses as related to phosphorus source, application method, and application rate on a Piedmont soil.

PubMed

Tarkalson, David D; Mikkelsen, Robert L

2004-01-01

Land application of animal manures and fertilizers has resulted in an increased potential for excessive P losses in runoff to nutrient-sensitive surface waters. The purpose of this research was to measure P losses in runoff from a bare Piedmont soil in the southeastern United States receiving broiler litter or inorganic P fertilizer either incorporated or surface-applied at varying P application rates (inorganic P, 0-110 kg P ha(-1); broiler litter, 0-82 kg P ha(-1)). Rainfall simulation was applied at a rate of 76 mm h(-1). Runoff samples were collected at 5-min intervals for 30 min and analyzed for reactive phosphorus (RP), algal-available phosphorus (AAP), and total phosphorus (TP). Incorporation of both P sources resulted in P losses not significantly different than the unfertilized control at all application rates. Incorporation of broiler litter decreased flow-weighted concentration of RP in runoff by 97% and mass loss of TP in runoff by 88% compared with surface application. Surface application of broiler litter resulted in runoff containing between 2.3 and 21.8 mg RP L(-1) for application rates of 8 to 82 kg P ha(-1), respectively. Mass loss of TP in runoff from surface-applied broiler litter ranged from 1.3 to 8.5 kg P ha(-1) over the same application rates. Flow-weighted concentrations of RP and mass losses of TP in runoff were not related to application rate when inorganic P fertilizer was applied to the soil surface. Results for this study can be used by P loss assessment tools to fine-tune P source, application rate, and application method site factors, and to estimate extreme-case P loss from cropland receiving broiler litter and inorganic P fertilizers.

Water-quality characteristics in runoff for three discovery farms in North Dakota, 2008-12

USGS Publications Warehouse

Nustad, Rochelle A.; Rowland, Kathleen M.; Wiederholt, Ronald

2015-01-01

Consistent patterns in water quality emerged at each individual farm, but similarities among farms also were observed. Suspended sediment, total phosphorus, and ammonia concentrations generally decreased downstream from feeding areas, and were primarily affected by surface runoff processes such as dilution, settling out of sediment, or vegetative uptake. Because surface runoff affects these constituents, increased annual surface runoff volume tended to result in increased loads and yields. No significant change in nitrate plus nitrite concentration were observed downstream from feeding areas because additional processes such as high solubility, nitrification, denitrification, and surface-groundwater interaction affect nitrate plus nitrite. For nitrate plus nitrite, increases in annual runoff volume did not consistently relate to increases in annual loads and yields. It seems that temporal distribution of precipitation and surface-groundwater interaction affected nitrate plus nitrite loads and yields. For surface drainage sites, the primary form of nitrogen was organic nitrogen whereas for subsurface drainage sites, the primary form of nitrogen was nitrate plus nitrite nitrogen.

Simulation of torrential rain as a means for assessment of surface runoff coefficients and calculation of recurrent design events in alpine catchments

NASA Astrophysics Data System (ADS)

Markart, Gerhard; Kohl, Bernhard; Sotier, Bernadette; Klebinder, Klaus; Schauer, Thomas; Bunza, Günther

2010-05-01

Simulation of heavy rain is an established method for studying infiltration characteristics, runoff and erosion behaviour in alpine catchments. Accordingly for characterization and differentiation of various runoff producing areas in alpine catchments transportable spray irrigation installations for large plots have been developed at the BFW, Department of Natural Hazards and Alpine Timberline, in Innsbruck, Austria. One installation has been designed for assessment of surface runoff coefficients under convective torrential rain with applicable precipitation intensities between 30 and 120 mm*h-1 and a plot size between 50 and 100 m2. The second device is used for simulation of persistent rain events (rain intensity about 10 mm*h-1, plot size: 400-1200 m2). Very reasonable results have been achieved during the comparison with spray irrigations from other institutions (e.g. Bavarian Environmental Agency in Munich) in the field. Rain simulations at BFW are mostly combined with comprehensive additional investigations on land-use, vegetation cover, soil physical characteristics, soil humidity, hydrogeology and other features of the test-sites. This allows proper interpretation of the achieved runoff data. At the moment results from more than 280 rain simulations are available from about 25 catchments / regions of the Eastern Alps at the BFW. Results show that the surface runoff coefficient, when runoff is constant at the test site (φconst) increases only slightly between rain intensities from 30 to 120 mm*h-1 (increment is 6%). Therefore φconst shall be used for assessment of runoff behaviour of runoff contributing areas, because it is less dependent form system conditions than φtot. BFW-data have been consolidated with results of the LfU (Bavarian Environmental Agency in Munich) in a data base and formed the basis for the development of a simple code of practice for assessment of surface runoff coefficients in torrential rain. The manual is freely available under: http://bfw.ac.at/rz/bfwcms.web?dok=4342 (in German language). The runoff contributing areas delineated by use of the manual in the field can be compiled in digital surface runoff coefficient maps and surface roughness maps. These maps in Austria form the basis for calculation of recurrent design events by use of precipitation/runoff models (P/R-models) like ZEMOKOST (optimized runtime method after Zeller = ZEller MOdified by KOhl and STepanek) or HEC-HMS. The result is substantial information on runoff disposition in each sub-catchment and hydrographs showing peak runoff and runoff freight. The code of practice for assessment of surface runoff coefficients has become the standard procedure in Austria to derive input parameters for P/R-models in practice. Recent investigations done at the Institute of Geography at the University of Berne show that the code of practice is suitable for application in catchments at the northern edge of the Swiss Alps too.

Evaluation of nitrogen and phosphorus transport with runoff from fairway turf managed with hollow tine core cultivation and verticutting.

PubMed

Rice, Pamela J; Horgan, Brian P

2013-07-01

Enrichment of surface waters with excess nutrients is associated with increased algal blooms, euthrophication and hypoxic zones, as reported in the northern Gulf of Mexico. A source of nutrients to surface waters results from fertilizer runoff. Management strategies used to maintain turf on golf courses and recreational fields often include aerification and application of fertilizer. Although research exists on benefits of core cultivation and verticutting (VC) to reduce thatch and the transport of applied chemicals with runoff, there are no studies reporting the effect of coupling these management practices with the goal of further reduction of off-site transport of fertilizer with runoff. We hypothesized that the addition of VC to hollow tine core cultivation (HTCC) would enhance infiltration of precipitation, reduce runoff and nutrient transport with runoff and therefore influence concentrations of nutrients in surface waters receiving runoff from turf managed as a golf course fairway. Greater runoff and mass of soluble phosphorus and ammonium nitrogen transported with runoff were measured from plots managed with HTCC+VC than HTCC; however, the reverse was noted for nitrate nitrogen. Only a portion of the observed trends proved to be statistically significant. Our research showed no reduction or enhancement of risk associated with surface water concentrations of phosphorus or nitrogen, resulting from runoff from creeping bentgrass turf that was managed with HTCC+VC compared to HTCC. Data obtained in this research will be useful to grounds superintendents when selecting best management practices and to scientists seeking data relating runoff to land management for watershed-scale modeling. Published by Elsevier B.V.

Transport of three veterinary antimicrobials from feedlot pens via simulated rainfall runoff.

PubMed

Sura, Srinivas; Degenhardt, Dani; Cessna, Allan J; Larney, Francis J; Olson, Andrew F; McAllister, Tim A

2015-07-15

Veterinary antimicrobials are introduced to wider environments by manure application to agricultural fields or through leaching or runoff from manure storage areas (feedlots, stockpiles, windrows, lagoons). Detected in manure, manure-treated soils, and surface and ground water near intensive cattle feeding operations, there is a concern that environmental contamination by these chemicals may promote the development of antimicrobial resistance in bacteria. Surface runoff and leaching appear to be major transport pathways by which veterinary antimicrobials eventually contaminate surface and ground water, respectively. A study was conducted to investigate the transport of three veterinary antimicrobials (chlortetracycline, sulfamethazine, tylosin), commonly used in beef cattle production, in simulated rainfall runoff from feedlot pens. Mean concentrations of veterinary antimicrobials were 1.4 to 3.5 times higher in surface material from bedding vs. non-bedding pen areas. Runoff rates and volumetric runoff coefficients were similar across all treatments but both were significantly higher from non-bedding (0.53Lmin(-1); 0.27) than bedding areas (0.40Lmin(-1); 0.19). In keeping with concentrations in pen surface material, mean concentrations of veterinary antimicrobials were 1.4 to 2.5 times higher in runoff generated from bedding vs. non-bedding pen areas. Water solubility and sorption coefficient of antimicrobials played a role in their transport in runoff. Estimated amounts of chlortetracycline, sulfamethazine, and tylosin that could potentially be transported to the feedlot catch basin during a one in 100-year precipitation event were 1.3 to 3.6ghead(-1), 1.9ghead(-1), and 0.2ghead(-1), respectively. This study demonstrates the magnitude of veterinary antimicrobial transport in feedlot pen runoff and supports the necessity of catch basins for runoff containment within feedlots. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

Stormwater runoff plumes in the Southern California Bight: A comparison study with SAR and MODIS imagery.

PubMed

Holt, Benjamin; Trinh, Rebecca; Gierach, Michelle M

2017-05-15

Stormwater runoff is the largest source of pollution in the Southern California Bight (SCB), resulting from untreated runoff and pollutants from urban watersheds entering the coastal waters after rainstorms. We make use of both satellite SAR and MODIS-Aqua ocean color imagery to examine two different components of runoff plumes, the surface slick and the sediment discharge. We expand on earlier satellite SAR studies by examining an extensive collection of multi-platform SAR imagery, spanning from 1992 to 2014, that provides a more comprehensive view of the plume surface slick characteristics, illustrated with distribution maps of the extent and flow direction of the plumes. The SAR-detected surface plumes are compared with coincident rain and runoff measurements, and with available measured shoreline fecal bacteria loads. We illustrate differences in the detection of SAR surface plumes with the sediment-related discharge plumes derived from MODIS imagery. A conceptual satellite stormwater runoff monitoring approach is presented. Copyright © 2017 Elsevier Ltd. All rights reserved.

Simulated rain events on an urban roadway to understand the dynamics of mercury mobilization in stormwater runoff.

PubMed

Eckley, Chris S; Branfireun, Brian

2009-08-01

This research focuses on mercury (Hg) mobilization in stormwater runoff from an urban roadway. The objectives were to determine: how the transport of surface-derived Hg changes during an event hydrograph; the influence of antecedent dry days on the runoff Hg load; the relationship between total suspended sediments (TSS) and Hg transport, and; the fate of new Hg input in rain and its relative importance to the runoff Hg load. Simulated rain events were used to control variables to elucidate transport processes and a Hg stable isotope was used to trace the fate of Hg inputs in rain. The results showed that Hg concentrations were highest at the beginning of the hydrograph and were predominantly particulate bound (HgP). On average, almost 50% of the total Hg load was transported during the first minutes of runoff, underscoring the importance of the initial runoff on load calculations. Hg accumulated on the road surface during dry periods resulting in the Hg runoff load increasing with antecedent dry days. The Hg concentrations in runoff were significantly correlated with TSS concentrations (mean r(2)=0.94+/-0.09). The results from the isotope experiments showed that the new Hg inputs quickly become associated with the surface particles and that the majority of Hg in runoff is derived from non-event surface-derived sources.

Colloidal mobilization of arsenic from mining-affected soils by surface runoff.

PubMed

Gomez-Gonzalez, Miguel Angel; Voegelin, Andreas; Garcia-Guinea, Javier; Bolea, Eduardo; Laborda, Francisco; Garrido, Fernando

2016-02-01

Scorodite-rich wastes left as a legacy of mining and smelting operations pose a threat to environmental health. Colloids formed by the weathering of processing wastes may control the release of arsenic (As) into surface waters. At a former mine site in Madrid (Spain), we investigated the mobilization of colloidal As by surface runoff from weathered processing wastes and from sediments in the bed of a draining creek and a downstream sedimentation-pond. Colloids mobilized by surface runoff during simulated rain events were characterized for their composition, structure and mode of As uptake using asymmetric flow field-flow fractionation coupled to inductively plasma mass spectrometry (AF4-ICP-MS) and X-ray absorption spectroscopy (XAS) at the As and Fe K-edges. Colloidal scorodite mobilized in surface runoff from the waste pile is acting as a mobile As carrier. In surface runoff from the river bed and the sedimentation pond, ferrihydrite was identified as the dominant As-bearing colloidal phase. The results from this study suggest that mobilization of As-bearing colloids by surface runoff may play an important role in the dispersion of As from metallurgical wastes deposited above ground and needs to be considered in risk assessment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Surface-water hydrology and runoff simulations for three basins in Pierce County, Washington

USGS Publications Warehouse

Mastin, M.C.

1996-01-01

The surface-water hydrology in Clear, Clarks, and Clover Creek Basins in central Pierce County, Washington, is described with a conceptual model of the runoff processes and then simulated with the Hydrological Simulation Program-FORTRAN (HSPF), a continuous, deterministic hydrologic model. The study area is currently undergoing a rapid conversion of rural, undeveloped land to urban and suburban land that often changes the flow characteristics of the streams that drain these lands. The complex interactions of land cover, climate, soils, topography, channel characteristics, and ground- water flow patterns determine the surface-water hydrology of the study area and require a complex numerical model to assess the impact of urbanization on streamflows. The U.S. Geological Survey completed this investigation in cooperation with the Storm Drainage and Surface Water Management Utility within the Pierce County Department of Public Works to describe the important rainfall-runoff processes within the study area and to develop a simulation model to be used as a tool to predict changes in runoff characteristics resulting from changes in land use. The conceptual model, a qualitative representation of the study basins, links the physical characteristics to the runoff process of the study basins. The model incorporates 11 generalizations identified by the investigation, eight of which describe runoff from hillslopes, and three that account for the effects of channel characteristics and ground-water flow patterns on runoff. Stream discharge was measured at 28 sites and precipitation was measured at six sites for 3 years in two overlapping phases during the period of October 1989 through September 1992 to calibrate and validate the simulation model. Comparison of rainfall data from October 1989 through September 1992 shows the data-collection period beginning with 2 wet water years followed by the relatively dry 1992 water year. Runoff was simulated with two basin models-the Clover Creek Basin model and the Clear-Clarks Basin model-by incorporating the generalizations of the conceptual model into the construction of two HSPF numerical models. Initially, the process-related parameters for runoff from glacial-till hillslopes were calibrated with numerical models for three catchment sites and one headwater basin where streamflows were continuously measured and little or no influence from ground water, channel storage, or channel losses affected runoff. At one of the catchments soil moisture was monitored and compared with simulated soil moisture. The values for these parameters were used in the basin models. Basin models were calibrated to the first year of observed streamflow data by adjusting other parameters in the numerical model that simulated channel losses, simulated channel storage in a few of the reaches in the headwaters and in the floodplain of the main stem of Clover Creek, and simulated volume and outflow of the ground-water reservoir representing the regional ground-water aquifers. The models were run for a second year without any adjustments, and simulated results were compared with observed results as a measure of validation of the models. The investigation showed the importance of defining the ground-water flow boundaries and demonstrated a simple method of simulating the influence of the regional ground-water aquifer on streamflows. In the Clover Creek Basin model, ground-water flow boundaries were used to define subbasins containing mostly glacial outwash soils and not containing any surface drainage channels. In the Clear-Clarks Basin model, ground-water flow boundaries outlined a recharge area outside the surface-water boundaries of the basin that was incorporated into the model in order to provide sufficient water to balance simulated ground-water outflows to the creeks. A simulated ground-water reservoir used to represent regional ground-water flow processes successfully provided the proper water balance of inflows and outfl

Nutrient loss with runoff from fairway turf: an evaluation of core cultivation practices and their environmental impact.

PubMed

Rice, Pamela J; Horgan, Brian P

2011-11-01

The presence of excess nutrients in surface waters can result in undesirable environmental and economic consequences, including nuisance algal blooms and eutrophication. Fertilizer use in highly managed turf systems has raised questions concerning the contribution of nutrients to surrounding surface waters. Experiments were designed to quantify phosphorus and nitrogen transport with runoff from turf plots maintained as a golf course fairway to identify which cultural practice, solid tine (ST) or hollow tine (HT) core cultivation, maximized phosphorus and nitrogen retention at the site of fertilizer application. Simulated precipitation and collection of resulting runoff were completed 26 ± 13 h following granular fertilizer application (18-3-18: N-P₂O₅-K₂O) and 63 d and 2 d following core cultivation. Runoff volumes were reduced in fairway turf plots aerated with HT relative to ST (63 d: 10%, 2 d: 55% reduction). Analysis of the runoff revealed a reduction in soluble phosphorus, ammonium nitrogen, and nitrate nitrogen losses with runoff from plots managed with HT; a 5 to 27% reduction after 63 d; and a 39 to 77% reduction at 2 d. Golf course runoff-to-surface water scenarios were used to calculate estimated environmental concentrations (EECs) of nitrogen and phosphorus in surface water receiving runoff from turf managed with ST or HT core cultivation. Surface water concentrations of phosphorus remained above the U.S. Environmental Protection Agency's water quality criteria to limit eutrophication, with the exception of concentrations associated with HT core cultivation at 2 d. Regardless of management practice (ST or HT) and time between core cultivation and runoff (63 d or 2 d), all EECs of nitrogen were below levels associated with increased algal growth. Understanding nutrient transport with runoff and identifying strategies that reduce off-site transport will increase their effectiveness at intended sites of application and minimize undesirable effects to surrounding surface water resources. Copyright © 2011 SETAC.

Runoff processes in catchments with a small scale topography

NASA Astrophysics Data System (ADS)

Feyen, H.; Leuenberger, J.; Papritz, A.; Gysi, M.; Flühler, H.; Schleppi, P.

1996-05-01

How do runoff processes influence nitrogen export from forested catchments? To support nitrogen balance studies for three experimental catchments (1500m 2) in the Northern Swiss prealps water flow processes in the two dominating soil types are monitored. Here we present the results for an experimental wetland catchment (1500m 2) and for a delineated sloped soil plot (10m 2), both with a muck humus topsoil. Runoff measurements on both the catchment and the soil plot showed fast reactions of surface and subsurface runoff to rainfall inputs, indicating the dominance of fast-flow paths such as cracks and fissures. Three quarters of the runoff from the soil plot can be attributed to water flow in the gleyic, clayey subsoil, 20% to flow in the humic A horizon and only 5% to surface runoff. The water balance for the wetland catchment was closed. The water balance of the soil plot did not close. Due to vertical upward flow from the saturated subsoil into the upper layers, the surface runoff plus subsurface runoff exceeded the input (precipitation) to the plot.

On the estimate of the Vegetation effects on the surface runoff through a plot scale rainfall simulator in Sardinia, Italy.

NASA Astrophysics Data System (ADS)

Corona, R.; Montaldo, N.; Cortis, C.; Albertson, J. D.

2012-04-01

In semi-arid regions with the Mediterranean climate of cool, wet winters and hot, dry summers, precipitation timing and amount, vegetation growth, and surface runoff are tightly intertwined. In the experimental site of Sardinia, the main source of water is surface reservoirs that are recharged by surface runoff in the rainy winter season. However, changes in climate are expected to bring both an overall decrease in winter precipitation and increased interannual variability of precipitation to this region. These changes may affect characteristics of the water-limited vegetation growth such as timing and production, and consequently change the amount of overland flow and reservoir recharge. Currently, there is little research on the combination of these effects; therefore, the goal of this research is to assess the runoff response of the land surface with varying vegetation states to ultimately predict how changes in the climate of Mediterranean watersheds may affect the needs of water resource management. A 4 m by 4 m rainfall simulator was designed, constructed, and tested as the first stage of this research. The rainfall simulator consisted of four independent lines of low-cost pressure washing nozzles operated at a pressure of 80 mbar, with the number of nozzles determining the rainfall intensity delivered to the plot. The rainfall intensity of the simulator varies from approximately 26 to 52 mm/h with a coefficient of uniformity ranging from 0.40 to 0.59. Measurements taken include surface runoff using a tipping bucket flow meter and soil moisture throughout the plot. Literature models for surface runoff predictions (Philips, Horton, Green Ampt, Soil conservation Service model, bucket model) are widely tested highlighting the typical hortonian behavior of this soil. The simulator was used to monitor changes in the surface runoff throughout the seasons (July 2010, August 2010, June 2011, July 2011, December 2011, January 2012) as the vegetation changes. Results shows the great impact of changes in vegetation cover on soil runoff processes: the increase of LAI from values of 0 to 1.5 produces a decrease of surface runoff of the 50%.

A 3-step framework for understanding the added value of surface soil moisture measurements for large-scale runoff prediction via data assimilation - a synthetic study in the Arkansas-Red River basin

NASA Astrophysics Data System (ADS)

Mao, Y.; Crow, W. T.; Nijssen, B.

2017-12-01

Soil moisture (SM) plays an important role in runoff generation both by partitioning infiltration and surface runoff during rainfall events and by controlling the rate of subsurface flow during inter-storm periods. Therefore, more accurate SM state estimation in hydrologic models is potentially beneficial for streamflow prediction. Various previous studies have explored the potential of assimilating SM data into hydrologic models for streamflow improvement. These studies have drawn inconsistent conclusions, ranging from significantly improved runoff via SM data assimilation (DA) to limited or degraded runoff. These studies commonly treat the whole assimilation procedure as a black box without separating the contribution of each step in the procedure, making it difficult to attribute the underlying causes of runoff improvement (or the lack thereof). In this study, we decompose the overall DA process into three steps by answering the following questions (3-step framework): 1) how much can assimilation of surface SM measurements improve surface SM state in a hydrologic model? 2) how much does surface SM improvement propagate to deeper layers? 3) How much does (surface and deeper-layer) SM improvement propagate into runoff improvement? A synthetic twin experiment is carried out in the Arkansas-Red River basin ( 600,000 km2) where a synthetic "truth" run, an open-loop run (without DA) and a DA run (where synthetic surface SM measurements are assimilated) are generated. All model runs are performed at 1/8 degree resolution and over a 10-year period using the Variable Infiltration Capacity (VIC) hydrologic model at a 3-hourly time step. For the DA run, the ensemble Kalman filter (EnKF) method is applied. The updated surface and deeper-layer SM states with DA are compared to the open-loop SM to quantitatively evaluate the first two steps in the framework. To quantify the third step, a set of perfect-state runs are generated where the "true" SM states are directly inserted in the model to assess the maximum possible runoff improvement that can be achieved by improving SM states alone. Our results show that the 3-step framework is able to effectively identify the potential as well as bottleneck of runoff improvement and point out the cases where runoff improvement via assimilation of surface SM is prone to failure.

Seasonal patterns in nutrients, carbon, and algal responses in wadeable streams within three geographically distinct areas of the United States, 2007-08

USGS Publications Warehouse

Lee, Kathy E.; Lorenz, David L.; Petersen, James C.; Greene, John B.

2012-01-01

The U.S. Geological Survey determined seasonal variability in nutrients, carbon, and algal biomass in 22 wadeable streams over a 1-year period during 2007 or 2008 within three geographically distinct areas in the United States. The three areas are the Upper Mississippi River Basin (UMIS) in Minnesota, the Ozark Plateaus (ORZK) in southern Missouri and northern Arkansas, and the Upper Snake River Basin (USNK) in southern Idaho. Seasonal patterns in some constituent concentrations and algal responses were distinct. Nitrate concentrations were greatest during the winter in all study areas potentially because of a reduction in denitrification rates and algal uptake during the winter, along with reduced surface runoff. Decreases in nitrate concentrations during the spring and summer at most stream sites coincided with increased streamflow during the snowmelt runoff or spring storms indicating dilution. The continued decrease in nitrate concentrations during summer potentially is because of a reduction in nitrate inputs (from decreased surface runoff) or increases in biological uptake. In contrast to nitrate concentrations, ammonia concentrations varied among study areas. Ammonia concentration trends were similar at UMIS and USNK sampling sites with winter peak concentrations and rapid decreases in ammonia concentrations by spring or early summer. In contrast, ammonia concentrations at OZRK sampling sites were more variable with peak concentrations later in the year. Ammonia may accumulate in stream water in the winter under ice and snow cover at the UMIS and USNK sites because of limited algal metabolism and increased mineralization of decaying organic matter under reducing conditions within stream bottom sediments. Phosphorus concentration patterns and the type of phosphorus present changes with changing hydrologic conditions and seasons and varied among study areas. Orthophosphate concentrations tended to be greater in the summer at UMIS sites, whereas total phosphorus concentrations at most UMIS and USNK sites peaked in the spring during runoff and then decreased through the remainder of the sampling period. Total phosphorus and orthophosphate concentrations in OZRK streams peaked during summer indicating a runoff-based source of both nutrients. Orthophosphate concentrations may increase in streams in the late summer when surface runoff composes less of total streamflow, and when groundwater containing orthophosphate becomes a more dominant source in streams during lower flows. Seston chlorophyll a concentrations were greatest early in the growing season (spring), whereas the spring runoff events coincided with reductions in benthic algal chlorophyll a biomass likely because of scour of benthic algae from the channel bottom that are entrained in the water column during that period. Nitrate, ammonia, and orthophosphate concentrations also decreased during that same period, indicating dilution in the spring during runoff events. The data from this study indicate that the source of water (surface runoff or groundwater) to a stream and the intensity of major runoff events are important factors controlling instream concentrations. Biological processes appear to affect nutrient concentrations during more stable lower flow periods in later summer, fall, and winter when residence time of water in a channel is longer, which allows more time for biological uptake and transformations. Management of nutrient conditions in streams is challenging and requires an understanding of multiple factors that affect in-stream nutrient concentrations and biological uptake and growth.

Using a hybrid model to predict solute transfer from initially saturated soil into surface runoff with controlled drainage water.

PubMed

Tong, Juxiu; Hu, Bill X; Yang, Jinzhong; Zhu, Yan

2016-06-01

The mixing layer theory is not suitable for predicting solute transfer from initially saturated soil to surface runoff water under controlled drainage conditions. By coupling the mixing layer theory model with the numerical model Hydrus-1D, a hybrid solute transfer model has been proposed to predict soil solute transfer from an initially saturated soil into surface water, under controlled drainage water conditions. The model can also consider the increasing ponding water conditions on soil surface before surface runoff. The data of solute concentration in surface runoff and drainage water from a sand experiment is used as the reference experiment. The parameters for the water flow and solute transfer model and mixing layer depth under controlled drainage water condition are identified. Based on these identified parameters, the model is applied to another initially saturated sand experiment with constant and time-increasing mixing layer depth after surface runoff, under the controlled drainage water condition with lower drainage height at the bottom. The simulation results agree well with the observed data. Study results suggest that the hybrid model can accurately simulate the solute transfer from initially saturated soil into surface runoff under controlled drainage water condition. And it has been found that the prediction with increasing mixing layer depth is better than that with the constant one in the experiment with lower drainage condition. Since lower drainage condition and deeper ponded water depth result in later runoff start time, more solute sources in the mixing layer are needed for the surface water, and larger change rate results in the increasing mixing layer depth.

Impact of Grassed Waterways and Compost Filter Socks on the Quality of Surface Runoff from Corn Fields

USDA-ARS?s Scientific Manuscript database

Surface runoff from cropland frequently has high concentrations of nutrients and herbicides, particularly in the first few events after application. Grassed waterways can control erosion while transmitting this runoff offsite, but are generally ineffective in removing dissolved agrochemicals. In thi...

The impact of runoff and surface hydrology on Titan's climate

NASA Astrophysics Data System (ADS)

Faulk, Sean; Lora, Juan; Mitchell, Jonathan

2017-10-01

Titan’s surface liquid distribution has been shown by general circulation models (GCMs) to greatly influence the hydrological cycle. Simulations from the Titan Atmospheric Model (TAM) with imposed polar methane “wetlands” reservoirs realistically produce many observed features of Titan’s atmosphere, whereas “aquaplanet” simulations with a global methane ocean are not as successful. In addition, wetlands simulations, unlike aquaplanet simulations, demonstrate strong correlations between extreme rainfall behavior and observed geomorphic features, indicating the influential role of precipitation in shaping Titan’s surface. The wetlands configuration is, in part, motivated by Titan’s large-scale topography featuring low-latitude highlands and high-latitude lowlands, with the implication being that methane may concentrate in the high-latitude lowlands by way of runoff and subsurface flow. However, the extent to which topography controls the surface liquid distribution and thus impacts the global hydrological cycle by driving surface and subsurface flow is unclear. Here we present TAM simulations wherein the imposed wetlands reservoirs are replaced by a surface runoff scheme that allows surface liquid to self-consistently redistribute under the influence of topography. To isolate the singular impact of surface runoff on Titan’s climatology, we run simulations without parameterizations of subsurface flow and topography-atmosphere interactions. We discuss the impact of surface runoff on the surface liquid distribution over seasonal timescales and compare the resulting hydrological cycle to observed cloud and surface features, as well as to the hydrological cycles of the TAM wetlands and aquaplanet simulations. While still idealized, this more realistic representation of Titan’s hydrology provides new insight into the complex interaction between Titan’s atmosphere and surface, demonstrates the influence of surface runoff on Titan’s global climate, and lays the groundwork for further surface hydrology developments in Titan GCMs.

Pan-Arctic distributions of continental runoff in the Arctic Ocean.

PubMed

Fichot, Cédric G; Kaiser, Karl; Hooker, Stanford B; Amon, Rainer M W; Babin, Marcel; Bélanger, Simon; Walker, Sally A; Benner, Ronald

2013-01-01

Continental runoff is a major source of freshwater, nutrients and terrigenous material to the Arctic Ocean. As such, it influences water column stratification, light attenuation, surface heating, gas exchange, biological productivity and carbon sequestration. Increasing river discharge and thawing permafrost suggest that the impacts of continental runoff on these processes are changing. Here, a new optical proxy was developed and implemented with remote sensing to determine the first pan-Arctic distribution of terrigenous dissolved organic matter (tDOM) and continental runoff in the surface Arctic Ocean. Retrospective analyses revealed connections between the routing of North American runoff and the recent freshening of the Canada Basin, and indicated a correspondence between climate-driven changes in river discharge and tDOM inventories in the Kara Sea. By facilitating the real-time, synoptic monitoring of tDOM and freshwater runoff in surface polar waters, this novel approach will help understand the manifestations of climate change in this remote region.

Critical review: Copper runoff from outdoor copper surfaces at atmospheric conditions.

PubMed

Hedberg, Yolanda S; Hedberg, Jonas F; Herting, Gunilla; Goidanich, Sara; Odnevall Wallinder, Inger

2014-01-01

This review on copper runoff dispersed from unsheltered naturally patinated copper used for roofing and facades summarizes and discusses influencing factors, available literature, and predictive models, and the importance of fate and speciation for environmental risk assessment. Copper runoff from outdoor surfaces is predominantly governed by electrochemical and chemical reactions and is highly dependent on given exposure conditions (size, inclination, geometry, degree of sheltering, and orientation), surface parameters (age, patina composition, and thickness), and site-specific environmental conditions (gaseous pollutants, chlorides, rainfall characteristics (amount, intensity, pH), wind direction, temperature, time of wetness, season). The corrosion rate cannot be used to assess the runoff rate. The extent of released copper varies largely between different rain events and is related to dry and wet periods, dry deposition prior to the rain event and prevailing rain and patina characteristics. Interpretation and use of copper runoff data for environmental risk assessment and management need therefore to consider site-specific factors and focus on average data of long-term studies (several years). Risk assessments require furthermore that changes in copper speciation, bioavailability aspects, and potential irreversible retention on solid surfaces are considered, factors that determine the environmental fate of copper runoff from outdoor surfaces.

Why can postwildfire runoff and erosion vary from negligible to extreme?

NASA Astrophysics Data System (ADS)

Noske, P.; Nyman, P.; Lane, P. N. J.; Van der Sant, R.; Sheridan, G. J.

2016-12-01

Soil surface properties vary with aridity, as does runoff and erosion after wildfire. Here we draw on studies conducted in different upland eucalypt forests of Victoria Australia, to compare and contrast the hydrological effects of wildfire. The study central to this presentation was conducted in two small (0.2-0.3 ha) dry forested headwater catchments burned during the 2009 Black Saturday wildfire. Surface runoff ratios during rainfall events approached 0.45 in the first year postwildfire. High runoff ratios in these dry forests were attributed to wildfire-induced soil water repellency and inherently low hydraulic conductivity. Average annual sediment yields peaked at 10 t ha-1 during the first year before declining dramatically to background levels, suggesting high-magnitude erosion processes may become limited by sediment availability on hillslopes. Surface runoff and erosion differed substantially between the equatorial and polar-facing catchments; this was most likely due to higher rates of infiltration and surface roughness on polar-facing slopes. Data collected from a plot scale study from 5 different burned forest locations of differing aridity produced a range of runoff ratios that support the findings of the central study. Additional data from burned catchments supporting wetter forests are also presented to further illustrate the contrast in rates of runoff and recovery from a different forest type. Results show that rates of postwildfire erosion and runoff in eucalypt forests in south-east Australia are highly variable. Large differences in erosion and runoff occur with relatively small changes in aridity.

Evaluating GCM land surface hydrology parameterizations by computing river discharges using a runoff routing model: Application to the Mississippi basin

NASA Technical Reports Server (NTRS)

Liston, G. E.; Sud, Y. C.; Wood, E. F.

1994-01-01

To relate general circulation model (GCM) hydrologic output to readily available river hydrographic data, a runoff routing scheme that routes gridded runoffs through regional- or continental-scale river drainage basins is developed. By following the basin overland flow paths, the routing model generates river discharge hydrographs that can be compared to observed river discharges, thus allowing an analysis of the GCM representation of monthly, seasonal, and annual water balances over large regions. The runoff routing model consists of two linear reservoirs, a surface reservoir and a groundwater reservoir, which store and transport water. The water transport mechanisms operating within these two reservoirs are differentiated by their time scales; the groundwater reservoir transports water much more slowly than the surface reservior. The groundwater reservior feeds the corresponding surface store, and the surface stores are connected via the river network. The routing model is implemented over the Global Energy and Water Cycle Experiment (GEWEX) Continental-Scale International Project Mississippi River basin on a rectangular grid of 2 deg X 2.5 deg. Two land surface hydrology parameterizations provide the gridded runoff data required to run the runoff routing scheme: the variable infiltration capacity model, and the soil moisture component of the simple biosphere model. These parameterizations are driven with 4 deg X 5 deg gridded climatological potential evapotranspiration and 1979 First Global Atmospheric Research Program (GARP) Global Experiment precipitation. These investigations have quantified the importance of physically realistic soil moisture holding capacities, evaporation parameters, and runoff mechanisms in land surface hydrology formulations.

Hydrological Cycle in the Heihe River Basin and Its Implication for Water Resource Management in Inland River Basins (Invited)

NASA Astrophysics Data System (ADS)

Li, X.; Cheng, G.; Tian, W.; Zhang, Y.; Zhou, J.; Pan, X.; Ge, Y.; Hu, X.

2013-12-01

Inland river basins take about 11.4% of the land area of the world and most of them are distributed over arid regions. Understanding the hydrological cycle of inland river basin is important for water resource management in water scarcity regions. This paper illustrated hydrological cycle of a typical inland river basin in China, the Heihe River Basin (HRB). First, water balance in upper, middle and lower reaches of the HRB was conceptualized by analyzing dominant hydrological processes in different parts of the river basin. Then, we used a modeling approach to study the water cycle in the HRB. In the upper reaches, we used the GBHM-SHAW, a distributed hydrological model with a new frozen soil parameterization. In the middle and lower reaches, we used the GWSiB, a three-dimensionally coupled land surface-groundwater model. Modeling results were compared with water balance observations in different landscapes and cross-validated with other results to ensure the reliability. The results show that the hydrological cycle in HRB has some distinctive characteristics. Mountainous area generates almost all of the runoff for the whole river basin. High-elevation zones have much larger runoff/precipitation ratio. Cryospheric hydrology plays an important role. Although snow melting and glacier runoff take less than 25% of total runoff, these processes regulate inter-annual variation of runoff and thus provide stable water resource for oases downstream. Forest area contributes almost no runoff but it smoothes runoff and reduces floods by storing water in soil and releasing it out slowly. In the middle reaches, artificial hydrological cycle is much more dominated than natural one. River water and groundwater, recharged by runoff from mountainous area, is the water resource to support the agriculture and nurture the riparian ecosystem. Precipitation, approximately 150 mm in average, is only a supplement to agriculture use but sufficient to sustain desert vegetation. Water resources are redistributed by very developed and extensive irrigation system. Irrigation water balance is complex because of strong interactions among surface, ground, river and irrigation water. Lower reaches is an extremely arid environment. Water availability in lower reaches has a great impact on the evolution of natural ecosystem and vice versa the landscape change reshapes the hydrological cycle. After the water resource reallocation project implemented in 2000, the water delivered to lower reaches has increased by 36%. Of all the available water resource, about 10% is used to sustain a terminal lake and other water bodies, 20% is used for irrigation to support very rapidly increased farmlands, 40-50% is used to nurture the natural oasis, and other water is lost due to evaporation. The features of hydrological cycle in the HRB is very typical for inland river basins in China's arid region. In this region, air temperature is rising and precipitation is most likely to increase. Accelerating glacier retreat will also produce more water. However, water demand increases more rapidly due to quickly developing economy and growing population. Therefore, how to turn our understanding of hydrological cycle in this environmental fragile region into more rational water resource management is a grand challenge.

Multivariate analysis for stormwater quality characteristics identification from different urban surface types in macau.

PubMed

Huang, J; Du, P; Ao, C; Ho, M; Lei, M; Zhao, D; Wang, Z

2007-12-01

Statistical analysis of stormwater runoff data enables general identification of runoff characteristics. Six catchments with different urban surface type including roofs, roadway, park, and residential/commercial in Macau were selected for sampling and study during the period from June 2005 to September 2006. Based on univariate statistical analysis of data sampled, major pollutants discharged from different urban surface type were identified. As for iron roof runoff, Zn is the most significant pollutant. The major pollutants from urban roadway runoff are TSS and COD. Stormwater runoff from commercial/residential and Park catchments show high level of COD, TN, and TP concentration. Principal component analysis was further done for identification of linkages between stormwater quality and urban surface types. Two potential pollution sources were identified for study catchments with different urban surface types. The first one is referred as nutrients losses, soil losses and organic pollutants discharges, the second is related to heavy metals losses. PCA was proved to be a viable tool to explain the type of pollution sources and its mechanism for different urban surface type catchments.

Urban Land: Study of Surface Run-off Composition and Its Dynamics

NASA Astrophysics Data System (ADS)

Palagin, E. D.; Gridneva, M. A.; Bykova, P. G.

2017-11-01

The qualitative composition of urban land surface run-off is liable to significant variations. To study surface run-off dynamics, to examine its behaviour and to discover reasons of these variations, it is relevant to use the mathematical apparatus technique of time series analysis. A seasonal decomposition procedure was applied to a temporary series of monthly dynamics with the annual frequency of seasonal variations in connection with a multiplicative model. The results of the quantitative chemical analysis of surface wastewater of the 22nd Partsjezd outlet in Samara for the period of 2004-2016 were used as basic data. As a result of the analysis, a seasonal pattern of variations in the composition of surface run-off in Samara was identified. Seasonal indices upon 15 waste-water quality indicators were defined. BOD (full), suspended materials, mineralization, chlorides, sulphates, ammonium-ion, nitrite-anion, nitrate-anion, phosphates (phosphorus), iron general, copper, zinc, aluminium, petroleum products, synthetic surfactants (anion-active). Based on the seasonal decomposition of the time series data, the contribution of trends, seasonal and accidental components of the variability of the surface run-off indicators was estimated.

Runoff quality from no-till cotton fertilized with broiler litter in subsurface bands.

PubMed

Adeli, A; Tewolde, H; Shankle, M W; Way, T R; Brooks, J P; McLaughlin, M R

2013-01-01

Surface broadcast of broiler litter to no-till row crops exposes the litter and its nutrients to risks of loss in runoff water and volatilization and may limit the potential benefit of litter to the crops. Subsurface banding of litter could alleviate these risks. A field study was conducted in 2008 and 2009 on an upland Falkner silt loam soil to determine the effect of broiler litter placement on runoff nutrient losses from no-till cotton ( L.). Treatments included surface broadcast broiler litter applied manually, subsurface-banded litter applied by tractor-drawn equipment, and no broiler litter, all in combination with or without winter wheat ( L.) cover crop residue. Broiler litter rate was 5.6 Mg ha. The experimental design was a randomized complete block with a split-plot arrangement of treatments replicated three times. In 2008, simulated rainfall was used to generate runoff 27 d after litter application. Subsurface-banded litter reduced runoff total C, N, P, NH, NO, Cu, Zn and water-soluble P (WP) concentrations by 72, 64, 51, 49, 70, 36, 65, and 77%, respectively, compared with surface broadcast. The reductions were greater in 2009 where runoff occurred 1 d after litter application. Bacterial runoff was decreased by one log with subsurface-banded litter compared to surface broadcast. Except for C, NH, N, and WP, the presence of winter cover crop residue did not affect the load or runoff nutrient concentrations in either year. The results indicate that subsurface banding litter to no-till cotton substantially reduces nutrient and bacterial losses in runoff compared with surface broadcasting. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

EPA Permeable Surface Research - Poster

EPA Science Inventory

EPA recognizes permeable surfaces as an effective post-construction infiltration-based Best Management Practice to mitigate the adverse effects of stormwater runoff. The professional user community conceptually embraces permeable surfaces as a tool for making runoff more closely...

EPA Permeable Surface Research

EPA Science Inventory

EPA recognizes permeable surfaces as an effective post-construction infiltration-based Best Management Practice to mitigate the adverse effects of stormwater runoff. The professional user community conceptually embraces permeable surfaces as a tool for making runoff more closely...

Soil Erodibility Parameters Under Various Cropping Systems of Maize

NASA Astrophysics Data System (ADS)

van Dijk, P. M.; van der Zijp, M.; Kwaad, F. J. P. M.

1996-08-01

For four years, runoff and soil loss from seven cropping systems of fodder maize have been measured on experimental plots under natural and simulated rainfall. Besides runoff and soil loss, several variables have also been measured, including rainfall kinetic energy, degree of slaking, surface roughness, aggregate stability, soil moisture content, crop cover, shear strength and topsoil porosity. These variables explain a large part of the variance in measured runoff, soil loss and splash erosion under the various cropping systems. The following conclusions were drawn from the erosion measurements on the experimental plots (these conclusions apply to the spatial level at which the measurements were carried out). (1) Soil tillage after maize harvest strongly reduced surface runoff and soil loss during the winter; sowing of winter rye further reduced winter erosion, though the difference with a merely tilled soil is small. (2) During spring and the growing season, soil loss is reduced strongly if the soil surface is partly covered by plant residues; the presence of plant residue on the surface appeared to be essential in achieving erosion reduction in summer. (3) Soil loss reductions were much higher than runoff reductions; significant runoff reduction is only achieved by the straw system having flat-lying, non-fixed plant residue on the soil surface; the other systems, though effective in reducing soil loss, were not effective in reducing runoff.

Spatial heterogeneity of mobilization processes and input pathways of herbicides into a brook in a small agricultural catchment

NASA Astrophysics Data System (ADS)

Doppler, Tobias; Lück, Alfred; Popow, Gabriel; Strahm, Ivo; Winiger, Luca; Gaj, Marcel; Singer, Heinz; Stamm, Christian

2010-05-01

Soil applied herbicides can be transported from their point of application (agricultural field) to surface waters during rain events. There they can have harmful effects on aquatic species. Since the spatial distribution of mobilization and transport processes is very heterogeneous, the contributions of different fields to the total load in a surface water body may differ considerably. The localization of especially critical areas (contributing areas) can help to efficiently minimize herbicide inputs to surface waters. An agricultural field becomes a contributing area when three conditions are met: 1) herbicides are applied, 2) herbicides are mobilized on the field and 3) the mobilized herbicides are transported rapidly to the surface water. In spring 2009, a controlled herbicide application was performed on corn fields in a small (ca 1 km2) catchment with intensive crop production in the Swiss plateau. Subsequently water samples were taken at different locations in the catchment with a high temporal resolution during rain events. We observed both saturation excess and hortonian overland flow during the field campaign. Both can be important mobilization processes depending on the intensity and quantity of the rain. This can lead to different contributing areas during different types of rain events. We will show data on the spatial distribution of herbicide loads during different types of rain events. Also the connectivity of the fields with the brook is spatially heterogeneous. Most of the fields are disconnected from the brook by internal sinks in the catchment, which prevents surface runoff from entering the brook directly. Surface runoff from these disconnected areas can only enter the brook rapidly via macropore-flow into tile drains beneath the internal sinks or via direct shortcuts to the drainage system (maintenance manholes, farmyard or road drains). We will show spatially distributed data on herbicide concentration in purely subsurface systems which shows how important such input pathways can be.

Rainfall timing effect on concentrations of testosterone and estradiol in surface runoff from broiler litter applied to grassed plots

USDA-ARS?s Scientific Manuscript database

Broiler litter contains the sex hormones testosterone and estradiol, which may contaminate surface runoff following litter application to grasslands. This study was conducted to evaluate the effect of runoff occurring at different times after litter application and under different environmental con...

Evaluating the Soil Vulnerability Index (SVI), an index to characterize inherent vulnerability of croplands to runoff and leaching

USDA-ARS?s Scientific Manuscript database

Soil erosion and nutrient loss from surface runoff and sub-surface flows are critical problems for croplands in the United States. Assessing cropland vulnerability to runoff and leaching is needed for watershed or regional land use and land management planning and conservation resources allocation. ...

Transport of dissolved trace elements in surface runoff and leachate from a coastal plain soil after poultry litter application

USDA-ARS?s Scientific Manuscript database

The application of poultry (Gallus gallus domesticus) litter to agricultural soils may exacerbate losses of trace elements in runoff water, an emerging concern to water quality. We evaluated trace elements (arsenic, cadmium, copper, lead, manganese, mercury, selenium and zinc) in surface runoff and ...

Meltwater flux and runoff modeling in the abalation area of jakobshavn Isbrae, West Greenland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mernild, Sebastian Haugard; Chylek, Petr; Liston, Glen

2009-01-01

The temporal variability in surface snow and glacier melt flux and runoff were investigated for the ablation area of lakobshavn Isbrae, West Greenland. High-resolution meteorological observations both on and outside the Greenland Ice Sheet (GrIS) were used as model input. Realistic descriptions of snow accumulation, snow and glacier-ice melt, and runoff are essential to understand trends in ice sheet surface properties and processes. SnowModel, a physically based, spatially distributed meteorological and snow-evolution modeling system was used to simulate the temporal variability of lakobshavn Isbrre accumulation and ablation processes for 2000/01-2006/07. Winter snow-depth observations and MODIS satellite-derived summer melt observations weremore » used for model validation of accumulation and ablation. Simulations agreed well with observed values. Simulated annual surface melt varied from as low as 3.83 x 10{sup 9} m{sup 3} (2001/02) to as high as 8.64 x 10{sup 9} m{sup 3} (2004/05). Modeled surface melt occurred at elevations reaching 1,870 m a.s.l. for 2004/05, while the equilibrium line altitude (ELA) fluctuated from 990 to 1,210 m a.s.l. during the simulation period. The SnowModel meltwater retention and refreezing routines considerably reduce the amount of meltwater available as ice sheet runoff; without these routines the lakobshavn surface runoff would be overestimated by an average of 80%. From September/October through May/June no runoff events were simulated. The modeled interannual runoff variability varied from 1.81 x 10{sup 9} m{sup 3} (2001/02) to 5.21 x 10{sup 9} m{sup 3} (2004/05), yielding a cumulative runoff at the Jakobshavn glacier terminus of {approx}2.25 m w.eq. to {approx}4.5 m w.eq., respectively. The average modeled lakobshavn runoff of {approx}3.4 km{sup 3} y{sup -1} was merged with previous estimates of Jakobshavn ice discharge to quantify the freshwater flux to Illulissat Icefiord. For both runoff and ice discharge the average trends are similar, indicating increasing (insignificant) influx of freshwater to the Illulissat Icefiord for the period 2000/01-2006/07. This study suggests that surface runoff forms a minor part of the overall Jakobshavn freshwater flux to the fiord: around 7% ({approx}3.4 km{sup 3} y{sup -1}) of the average annual freshwater flux of {approx}51.0 km{sup 3} y{sup -1} originates from the surface runoff.« less

Nutrient loss in leachate and surface runoff from surface-broadcast and subsurface-banded broiler litter

USDA-ARS?s Scientific Manuscript database

Subsurface band application of poultry litter has been shown to reduce the transport of nutrients from fields in surface runoff, compared to the conventional surface broadcast application. Little in situ research has been conducted to determine effects of surface broadcast application and subsurfac...

Urban Runoff and Nutrients Loading Control from Sustainable BMPs (Invited)

NASA Astrophysics Data System (ADS)

Xiao, Q.

2009-12-01

Climate change alters hydrodynamic and nutrient dynamic in both large and small geographic scales. These changes in our freshwater system directly affect drinking water, food production, business, and all aspects of our life. Along with climate change is increasing urbanization which alters natural landscape. Urban runoff has been identified as one of many potential drivers of the decline of pelagic fishes in san Francisco Bay-Delta region. Recent found of Pyrethroids in American River has increased scientists, public, and policy makers’ concern about our fresh water system. Increasing our understanding about the fundamental hydrodynamic, nutrient dynamics, and the transport mechanics of runoff and nutrients are important for future water resource and ecosystem management. Urbanization has resulted in significantly increasing the amount of impervious land cover. Most impervious land covers are hydrophobic that alters surface runoff because of the effects on surface retention storage, rainfall interception, and infiltration. Large volumes of excess storm runoff from urbanized areas cause flooding, water pollution, groundwater recharge deficits, destroyed habitat, beach closures, and toxicity to aquatic organisms. Parking lot alone accounts for more than 11% of these impervious surfaces. Contrast to impervious parking lot, turfgrass can accouter for 12% of urban land in California. Irrigated urban landscapes create considerable benefits to our daily living. However, the use of fertilizers and pesticides has caused environmental problems. Preventing fertilizers and pesticides from entering storm drains is an important goal for both landscape and storm runoff managers. Studies of urban runoff have found that the most fertilizers and pesticides are from dry weather runoff which conveys pollutants to sidewalks, streets, and storm drains. Controlling surface runoff is critical to preventing these pollutants from entering storm drains and water bodies. Large scale construction of runoff retention basins and treatment facilities to meet TMDL (Total Maximum Daily Load) regulations are not cost-effective or practical. An alternative approach is to control runoff and nutrients on-site through installation of decentralized BMPs that detain and infiltrate runoff before it reaches storm drains. Recent developed green-infrastructure which integrating engineered soil and trees to reduce runoff and nutrients loading is a self-sustained best management practice (BMP). This BMP has been testing and used in urban runoff control. In Davis, CA this type of BMPs were installed in a parking lot and a residential property to evaluate the system’s effectiveness on reducing storm runoff and pollutant loading from the parking lot and irrigated landscape. Storm runoff and pollutant loading were measured and monitored during February 2007 thru May 2009 from the parking lot. The BMP reduced surface runoff and nutrients by 88.8% and 95.3%, respectively. In the residential irrigated landscape, the dry-weather runoff was monitored during 2007 irrigation season, the BMP captured almost all dry weather runoff. The performance of these BMPs demonstrated their potential use for reducing runoff and nutrients loading. Control urban runoff from these 23% landscape (i.e., parking lot and irrigated turf grass) could largely alter the runoff and nutrients transport and their dynamic in our water system.

Spatial variations of storm runoff pollution and their correlation with land-use in a rapidly urbanizing catchment in China.

PubMed

Qin, Hua-Peng; Khu, Soon-Thiam; Yu, Xiang-Ying

2010-09-15

The composition of land use for a rapidly urbanizing catchment is usually heterogeneous, and this may result in significant spatial variations of storm runoff pollution and increase the difficulties of water quality management. The Shiyan Reservoir catchment, a typical rapidly urbanizing area in China, is chosen as a study area, and temporary monitoring sites were set at the downstream of its 6 sub-catchments to synchronously measure rainfall, runoff and water quality during 4 storm events in 2007 and 2009. Due to relatively low frequency monitoring, the IHACRES and exponential pollutant wash-off simulation models are used to interpolate the measured data to compensate for data insufficiency. Three indicators, event pollutant loads per unit area (EPL), event mean concentration (EMC) and pollutant loads transported by the first 50% of runoff volume (FF50), were used to describe the runoff pollution for different pollutants in each sub-catchment during the storm events, and the correlations between runoff pollution spatial variations and land-use patterns were tested by Spearman's rank correlation analysis. The results indicated that similar spatial variation trends were found for different pollutants (EPL or EMC) in light storm events, which strongly correlate with the proportion of residential land use; however, they have different trends in heavy storm events, which correlate with not only the residential land use, but also agricultural and bare land use. And some pairs of pollutants (such as COD/BOD, NH(3)-N/TN) might have the similar source because they have strong or moderate positive spatial correlation. Moreover, the first flush intensity (FF50) varies with impervious land areas and different interception ratio of initial storm runoff volume should be adopted in different sub-catchments. Copyright 2010 Elsevier B.V. All rights reserved.

Dairy heifer manure management, dietary phosphorus, and soil test P effects on runoff phosphorus.

PubMed

Jokela, William E; Coblentz, Wayne K; Hoffman, Patrick C

2012-01-01

Manure application to cropland can contribute to runoff losses of P and eutrophication of surface waters. We conducted a series of three rainfall simulation experiments to assess the effects of dairy heifer dietary P, manure application method, application rate, and soil test P on runoff P losses from two successive simulated rainfall events. Bedded manure (18-21% solids) from dairy heifers fed diets with or without supplemental P was applied on a silt loam soil packed into 1- by 0.2-m sheet metal pans. Manure was either surface-applied or incorporated (Experiment 1) or surface-applied at two rates (Experiment 2) to supply 26 to 63 kg P ha. Experiment 3 evaluated runoff P from four similar nonmanured soils with average Bray P1-extractable P levels of 11, 29, 51, and 75 mg kg. We measured runoff quantity, total P (TP), dissolved reactive P (DRP), and total and volatile solids in runoff collected for 30 min after runoff initiation from two simulated rain events (70 mm h) 3 or 4 d apart. Manure incorporation reduced TP and DRP concentrations and load by 85 to 90% compared with surface application. Doubling the manure rate increased runoff DRP and TP concentrations an average of 36%. In the same experiment, P diet supplementation increased water-extractable P in manure by 100% and increased runoff DRP concentration threefold. Concentrations of solids, TP, and DRP in runoff from Rain 2 were 25 to 75% lower than from Rain 1 in Experiments 1 and 2. Runoff DRP from nonmanured soils increased quadratically with increasing soil test P. These results show that large reductions in P runoff losses can be achieved by incorporation of manure, avoiding unnecessary diet P supplementation, limiting manure application rate, and managing soils to prevent excessive soil test P levels. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

[Characterization and source apportionment of pollutants in urban roadway runoff in Chongqing].

PubMed

Zhang, Qian-Qian; Wang, Xiao-Ke; Hao, Li-Ling; Hou, Pei-Qiang; Ouyang, Zhi-Yun

2012-01-01

By investigating surface runoff from urban roadway in Chongqing, we assessed the characteristics of surface runoff pollution and the effect of rainfall intensity and antecedent dry weather period on water quality. Using multivariate statistical analysis of data of runoff quality, potential pollutants discharged from urban roadway runoff were identified. The results show that the roadway runoff has high levels of COD, TP and TN, the EMC were 60.83-208.03 mg x L(-1), 0.47-1.01 mg x L(-1) and 2.07-5.00 mg x L(-1) respectively, being the main pollutants; The peaks of pollutant concentration are ahead of or synchronous with the peak of runoff volume; the peaks of pollutant concentrations are mostly occurred within 10 minutes of rainfall. The heavy metal concentrations fluctuate dentately during runoff proceeding. Two potential pollution sources to urban roadway runoff apportioned by using principal component analysis are: vehicle's traffic loss and atmospheric dry and wet deposition, and municipal wastes.

Effect of climate change on runoff of Campylobacter and Cryptosporidium from land to surface water.

PubMed

Sterk, Ankie; Schijven, Jack; de Roda Husman, Ana Maria; de Nijs, Ton

2016-05-15

Faeces originating from wildlife, domestic animals or manure-fertilized fields, is considered an important source of zoonotic pathogens to which people may be exposed by, for instance, bathing or drinking-water consumption. An increase in runoff, and associated wash-off of animal faeces from fields, is assumed to contribute to the increase of disease outbreaks during periods of high precipitation. Climate change is expected to increase winter precipitation and extreme precipitation events during summer, but has simultaneously also other effects such as temperature rise and changes in evapotranspiration. The question is to what extent the combination of these effects influence the input of zoonotic pathogens to the surface waters. To quantitatively analyse the impacts of climate change on pathogen runoff, pathogen concentrations reaching surface waters through runoff were calculated by combining an input model for catchment pathogen loads with the Wageningen Lowland Runoff Simulator (WALRUS). Runoff of Cryptosporidium and Campylobacter was evaluated under different climate change scenarios and by applying different scenarios for sources of faecal pollution in the catchments, namely dairy cows and geese and manure fertilization. Model evaluation of these scenarios shows that climate change has little overall impact on runoff of Campylobacter and Cryptosporidium from land to the surface waters. Even though individual processes like runoff fluxes, pathogen release and dilution are affected, either positively or negatively, the net effect on the pathogen concentration in surface waters and consequently also on infection risks through recreation seems limited. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Modeling the risk of phosphorus runoff following single and split phosphorus fertilizer applications in two contrasting catchments.

PubMed

Burkitt, Lucy L; Dougherty, Warwick J; Corkrey, Ross; Broad, Shane T

2011-01-01

The potential loss of P in runoff is a function of the combined effects of fertilizer-soil interactions and climatic characteristics. In this study, we applied a Bayesian approach to experimental data to model the annualized long-term risk of P runoff following single and split P fertilizer applications using two example catchments with contrasting rainfall/runoff patterns. Split P fertilizer strategies are commonly used in intensive pasture production in Australia and our results showed that three applications of 13.3 kg P ha(-1) resulted in a greater risk of P runoff compared with a single application of 40 kg P ha(-1) when long-term surface runoff data were incorporated into a Bayesian P risk model. Splitting P fertilizer applications increased the likelihood of a coincidence of fertilizer application and runoff occurring. We found that the overall risk of P runoff is also increased in catchments where the rainfall/runoff pattern is less predictable, compared with catchments where rainfall/runoff is winter dominant. The findings of our study also question the effectiveness of current recommendations to avoid applying fertilizer if runoff is likely to occur in the next few days, as we found that total P concentrations at the half-life were still very high (18.2 and 8.2 mg P L(-1)) following single and split P treatments, respectively. Data from the current study also highlight that omitting P fertilizer on soils that already have adequate soil test P concentrations is an effective method of reducing P loss in surface runoff. If P fertilizer must be applied, we recommend less frequent applications and only during periods of the year when the risk of surface P runoff is low.

Runoff and solute mobilization processes in a semiarid headwater catchment

NASA Astrophysics Data System (ADS)

Hughes, Justin D.; Khan, Shahbaz; Crosbie, Russell S.; Helliwell, Stuart; Michalk, David L.

2007-09-01

Runoff and solute transport processes contributing to streamflow were determined in a small headwater catchment in the eastern Murray-Darling Basin of Australia using hydrometric and tracer methods. Streamflow and electrical conductivity were monitored from two gauges draining a portion of the upper catchment area (UCA) and a saline scalded area, respectively. Runoff in the UCA was related to the formation of a seasonally perched aquifer in the near-surface zone (0-0.4 m). A similar process was responsible for runoff generation in the saline scalded area. However, saturation in the scald area was related to the proximity of groundwater rather than low subsurface hydraulic conductivity. Because of higher antecedent water content, runoff commenced earlier in winter from the scald than did the UCA. Additionally, areal runoff from the scald was far greater than from the UCA. Total runoff from the UCA was higher than the scald (15.7 versus 3.5 mL), but salt export was far lower (0.6 and 5.4 t for the UCA and scald area, respectively) since salinity of the scald runoff was far higher than that from the UCA, indicating the potential impact of saline scalded areas at the catchment scale. End-member mixing analysis modeling using six solutes indicated that most runoff produced from the scald was "new" (40-71%) despite the proximity of the groundwater surface and the high antecedent moisture levels. This is a reflection of the very low hydraulic conductivity of soils in the study area. Nearly all chloride exported to the stream from the scald emanated from the near-surface zone (77-87%). Runoff and solute mobilization processes depend upon seasonal saturation occurring in the near-surface zone during periods of low evaporative demand and generation of saturated overland flow.

Simulation of Runoff Concentration on Arable Fields and the Impact of Adapted Tillage Practises

NASA Astrophysics Data System (ADS)

Winter, F.; Disse, M.

2012-04-01

Conservational tillage can reduce runoff on arable fields. Due to crop residues remaining on the fields a seasonal constant ground cover is achieved. This additional soil cover not only decreases the drying of the topsoil but also reduces the mechanical impact of raindrops and the possibly resulting soil crust. Further implications of the mulch layer can be observed during heavy precipitation events and occurring surface runoff. The natural roughness of the ground surface is further increased and thus the flow velocity is decreased, resulting in an enhanced ability of runoff to infiltrate into the soil (so called Runon-Infiltration). The hydrological model system WaSiM-ETH hitherto simulates runoff concentration by a flow time grid in the catchment, which is derived from topographical features of the catchment during the preprocessing analysis. The retention of both surface runoff and interflow is modelled by a single reservoir in every discrete flow time zone until the outlet of a subcatchment is reached. For a more detailed analysis of the flow paths in catchments of the lower mesoscale (< 1 km2) the model was extended by a kinematic wave approach for the surface runoff concentration. This allows the simulation of small-scale variation in runoff generation and its temporal distribution in detail. Therefore the assessment of adapted tillage systems can be derived. On singular fields of the Scheyern research farm north-west of Munich it can be shown how different crops and tillage practises can influence runoff generation and concentration during single heavy precipitation events. From the simulation of individual events in agricultural areas of the lower mesoscale hydrologically susceptible areas can be identified and the positive impact of an adapted agricultural management on runoff generation and concentration can be quantifed.

Surface runoff and nitrogen (N) loss in a bamboo (Phyllostachys pubescens) forest under different fertilization regimes.

PubMed

Zhang, Qichun; Shamsi, Imran Haider; Wang, Jinwen; Song, Qiujin; Xue, Qiaoyun; Yu, Yan; Lin, Xianyong; Hussain, Sayed

2013-07-01

Nitrogen (N) losses from agricultural fields have been extensively studied. In contrast, surface runoff and N losses have rarely been considered for bamboo forests that are widespread in regions such as southern China. The thriving of bamboo industries has led to increasing fertilizer use in bamboo forests. In this study, we evaluated surface runoff and N losses in runoff following different fertilization treatments under field conditions in a bamboo (Phyllostachys pubescens) forest in the catchment of Lake Taihu in Jiangsu, China. Under three different fertilization regimes, i.e., control, site-specific nutrient management (SSNM), and farmer's fertilization practice (FFP), the water runoff rate amounted to 356, 361, and 342 m(3) ha(-1) and accounted for 1.91, 1.98, and 1.85% of the water input, respectively, from June 2009 to May 2010. The total N losses via surface runoff ranged from 1.2 to 1.8 kg ha(-1). Compared with FFP, the SSNM treatment reduced total nitrogen (TN) and dissolved nitrogen (DN) losses by 31 and 34%, respectively. The results also showed that variations in N losses depended mainly on runoff fluxes, not N concentrations. Runoff samples collected from all treatments throughout the year showed TN concentrations greater than 0.35 mg L(-1), with the mean TN concentration in the runoff from the FFP treatment reaching 8.97 mg L(-1). The loss of NO3(-)-N was greater than the loss of NH4(+)-N. The total loss of dissolved organic nitrogen (DON) reached 23-41% of the corresponding DN. Therefore, DON is likely the main N species in runoff from bamboo forests and should be emphasized in the assessment and management of N losses in bamboo forest.

Wildfire impacts on the processes that generate debris flows in burned watersheds

USGS Publications Warehouse

Parise, M.; Cannon, S.H.

2012-01-01

Every year, and in many countries worldwide, wildfires cause significant damage and economic losses due to both the direct effects of the fires and the subsequent accelerated runoff, erosion, and debris flow. Wildfires can have profound effects on the hydrologic response of watersheds by changing the infiltration characteristics and erodibility of the soil, which leads to decreased rainfall infiltration, significantly increased overland flow and runoff in channels, and movement of soil. Debris-flow activity is among the most destructive consequences of these changes, often causing extensive damage to human infrastructure. Data from the Mediterranean area and Western United States of America help identify the primary processes that result in debris flows in recently burned areas. Two primary processes for the initiation of fire-related debris flows have been so far identified: (1) runoff-dominated erosion by surface overland flow; and (2) infiltration-triggered failure and mobilization of a discrete landslide mass. The first process is frequently documented immediately post-fire and leads to the generation of debris flows through progressive bulking of storm runoff with sediment eroded from the hillslopes and channels. As sediment is incorporated into water, runoff can convert to debris flow. The conversion to debris flow may be observed at a position within a drainage network that appears to be controlled by threshold values of upslope contributing area and its gradient. At these locations, sufficient eroded material has been incorporated, relative to the volume of contributing surface runoff, to generate debris flows. Debris flows have also been generated from burned basins in response to increased runoff by water cascading over a steep, bedrock cliff, and incorporating material from readily erodible colluvium or channel bed. Post-fire debris flows have also been generated by infiltration-triggered landslide failures which then mobilize into debris flows. However, only 12% of documented cases exhibited this process. When they do occur, the landslide failures range in thickness from a few tens of centimeters to more than 6 m, and generally involve the soil and colluvium-mantled hillslopes. Surficial landslide failures in burned areas most frequently occur in response to prolonged periods of storm rainfall, or prolonged rainfall in combination with rapid snowmelt or rain-on-snow events. ?? 2011 Springer Science+Business Media B.V.

Hydrological Footprints of Urban Developments in the Lake Simcoe Watershed, Canada: A Combined Paired-Catchment and Change Detection Modeling Approach

NASA Astrophysics Data System (ADS)

Oni, S. K.; Futter, M. N.; Buttle, J. M.; Dillon, P.

2014-12-01

Urban sprawl and regional climate variability are major stresses on surface water resources in many places. The Lake Simcoe watershed (LSW) Ontario, Canada, is no exception. The LSW is predominantly agricultural but is experiencing rapid population growth due to its proximity to the greater Toronto area. This has led to extensive land use changes which have impacted its water resources and altered runoff patterns in some rivers draining to the lake. Here, we use a paired-catchment approach, hydrological change detection modelling and remote sensing analysis of satellite images to evaluate the impacts of land use change on the hydrology of the LSW (1994 to 2008). Results show that urbanization increased up to 16% in Lovers Creek, the most-urban impacted catchment. Annual runoff from Lovers Creek increased from 239 to 442 mm/yr in contrast to the reference catchment (Black River at Washago) where runoff was relatively stable with an annual mean of 474 mm/yr. Increased annual runoff from Lovers Creek was not accompanied by an increase in annual precipitation. Discriminant function analysis suggests that early (1992-1997; pre-major development) and late (2004-2009; fully urbanized) periods for Lovers Creek separated mainly based on model parameter sets related to runoff flashiness and evapotranspiration. As a result, parameterization in either period cannot be used interchangeably to produce credible runoff simulations in Lovers Creek due to greater scatter between the parameters in canonical space. Separation of early and late period parameter sets for the reference catchment was based on climate and snowmelt related processes. This suggests that regional climatic variability could be influencing hydrologic change in the reference catchment whereas urbanization amplified the regional natural hydrologic changes in urbanizing catchments of the LSW.

Observed and simulated hydrologic response for a first-order catchment during extreme rainfall 3 years after wildfire disturbance

USGS Publications Warehouse

Ebel, Brian A.; Rengers, Francis K.; Tucker, Gregory E.

2016-01-01

Hydrologic response to extreme rainfall in disturbed landscapes is poorly understood because of the paucity of measurements. A unique opportunity presented itself when extreme rainfall in September 2013 fell on a headwater catchment (i.e., <1 ha) in Colorado, USA that had previously been burned by a wildfire in 2010. We compared measurements of soil-hydraulic properties, soil saturation from subsurface sensors, and estimated peak runoff during the extreme rainfall with numerical simulations of runoff generation and subsurface hydrologic response during this event. The simulations were used to explore differences in runoff generation between the wildfire-affected headwater catchment, a simulated unburned case, and for uniform versus spatially variable parameterizations of soil-hydraulic properties that affect infiltration and runoff generation in burned landscapes. Despite 3 years of elapsed time since the 2010 wildfire, observations and simulations pointed to substantial surface runoff generation in the wildfire-affected headwater catchment by the infiltration-excess mechanism while no surface runoff was generated in the unburned case. The surface runoff generation was the result of incomplete recovery of soil-hydraulic properties in the burned area, suggesting recovery takes longer than 3 years. Moreover, spatially variable soil-hydraulic property parameterizations produced longer duration but lower peak-flow infiltration-excess runoff, compared to uniform parameterization, which may have important hillslope sediment export and geomorphologic implications during long duration, extreme rainfall. The majority of the simulated surface runoff in the spatially variable cases came from connected near-channel contributing areas, which was a substantially smaller contributing area than the uniform simulations.

Grass mulching effect on infiltration, surface runoff and soil loss of three agricultural soils in Nigeria.

PubMed

Adekalu, K O; Olorunfemi, I A; Osunbitan, J A

2007-03-01

Mulching the soil surface with a layer of plant residue is an effective method of conserving water and soil because it reduces surface runoff, increases infiltration of water into the soil and retard soil erosion. The effectiveness of using elephant grass (Pennisetum purpureum) as mulching material was evaluated in the laboratory using a rainfall simulator set at rainfall intensities typical of the tropics. Six soil samples, two from each of the three major soil series representing the main agricultural soils in South Western Nigeria were collected, placed on three different slopes, and mulched with different rates of the grass. The surface runoff, soil loss, and apparent cumulative infiltration were then measured under each condition. The results with elephant grass compared favorably with results from previous experiments using rice straw. Runoff and soil loss decreased with the amount of mulch used and increased with slope. Surface runoff, infiltration and soil loss had high correlations (R = 0.90, 0.89, and 0.86, respectively) with slope and mulch cover using surface response analysis. The mean surface runoff was correlated negatively with sand content, while mean soil loss was correlated positively with colloidal content (clay and organic matter) of the soil. Infiltration was increased and soil loss was reduced greatly with the highest cover. Mulching the soils with elephant grass residue may benefit late cropping (second cropping) by increasing stored soil water for use during dry weather and help to reduce erosion on sloping land.

Pan-Arctic distributions of continental runoff in the Arctic Ocean

PubMed Central

Fichot, Cédric G.; Kaiser, Karl; Hooker, Stanford B.; Amon, Rainer M. W.; Babin, Marcel; Bélanger, Simon; Walker, Sally A.; Benner, Ronald

2013-01-01

Continental runoff is a major source of freshwater, nutrients and terrigenous material to the Arctic Ocean. As such, it influences water column stratification, light attenuation, surface heating, gas exchange, biological productivity and carbon sequestration. Increasing river discharge and thawing permafrost suggest that the impacts of continental runoff on these processes are changing. Here, a new optical proxy was developed and implemented with remote sensing to determine the first pan-Arctic distribution of terrigenous dissolved organic matter (tDOM) and continental runoff in the surface Arctic Ocean. Retrospective analyses revealed connections between the routing of North American runoff and the recent freshening of the Canada Basin, and indicated a correspondence between climate-driven changes in river discharge and tDOM inventories in the Kara Sea. By facilitating the real-time, synoptic monitoring of tDOM and freshwater runoff in surface polar waters, this novel approach will help understand the manifestations of climate change in this remote region. PMID:23316278

Transport of lincomycin to surface and ground water from manure-amended cropland.

PubMed

Kuchta, Sandra L; Cessna, Allan J; Elliott, Jane A; Peru, Kerry M; Headley, John V

2009-01-01

Livestock manure containing antimicrobials becomes a possible source of these compounds to surface and ground waters when applied to cropland as a nutrient source. The potential for transport of the veterinary antimicrobial lincomycin to surface waters via surface runoff and to leach to ground water was assessed by monitoring manure-amended soil, simulated rainfall runoff, snowmelt runoff, and ground water over a 2-yr period in Saskatchewan, Canada, after fall application of liquid swine manure to cropland. Liquid chromatography tandem mass spectrometry was used to quantify lincomycin in all matrix extracts. Initial concentrations in soil (46.3-117 mug kg(-1)) were not significantly different (p > 0.05) for manure application rates ranging from 60,000 to 95,000 L ha(-1) and had decreased to nondetectable levels by mid-summer the following year. After fall manure application, lincomycin was present in all simulated rainfall runoff (0.07-2.7 mug L(-1)) and all snowmelt runoff (0.038-3.2 mug L(-1)) samples. Concentrations in snowmelt runoff were not significantly different from those in simulated rainfall runoff the previous fall. On average, lincomycin concentrations in ephemeral wetlands dissipated by 50% after 31 d. Concentrations of lincomycin in ground water were generally <0.005 mug L(-1). This study demonstrates that the management practice of using livestock manure from confined animal feeding operations as a plant nutrient source on cropland may result in antimicrobial transport to surface and ground waters.

Responses of Surface Runoff to Climate Change and Human Activities in the Arid Region of Central Asia: A Case Study in the Tarim River Basin, China

NASA Astrophysics Data System (ADS)

Xu, Changchun; Chen, Yaning; Chen, Yapeng; Zhao, Ruifeng; Ding, Hui

2013-04-01

Based on hydrological and climatic data and land use/cover change data covering the period from 1957 to 2009, this paper investigates the hydrological responses to climate change and to human activities in the arid Tarim River basin (TRB). The results show that the surface runoff of three headstreams (Aksu River, Yarkant River and Hotan River) of the Tarim River exhibited a significant increasing trend since 1960s and entered an even higher-runoff stage in 1994. In the contrary, the surface runoff of Tarim mainstream displayed a persistent decreasing trend since 1960s. The increasing trend of surface runoff in the headstreams can be attributed to the combined effects of both temperature and precipitation changes during the past five decades. But, the decreasing trend of surface runoff in the mainstream and the observed alterations of the temporal and spatial distribution patterns were mainly due to the adverse impacts of human activities. Specifically, increasingly intensified water consumption for irrigation and the associated massive constructions of water conservancy projects were responsible for the decreasing trend of runoff in the mainstream. And, the decreasing trend has been severely jeopardizing the ecological security in the lower reaches. It is now unequivocally clear that water-use conflicts among different sectors and water-use competitions between upper and lower reaches are approaching to dangerous levels in TRB that is thus crying for implementing an integrated river basin management scheme.

Responses of surface runoff to climate change and human activities in the arid region of central Asia: a case study in the Tarim River basin, China.

PubMed

Xu, Changchun; Chen, Yaning; Chen, Yapeng; Zhao, Ruifeng; Ding, Hui

2013-04-01

Based on hydrological and climatic data and land use/cover change data covering the period from 1957 to 2009, this paper investigates the hydrological responses to climate change and to human activities in the arid Tarim River basin (TRB). The results show that the surface runoff of three headstreams (Aksu River, Yarkant River and Hotan River) of the Tarim River exhibited a significant increasing trend since 1960s and entered an even higher-runoff stage in 1994. In the contrary, the surface runoff of Tarim mainstream displayed a persistent decreasing trend since 1960s. The increasing trend of surface runoff in the headstreams can be attributed to the combined effects of both temperature and precipitation changes during the past five decades. But, the decreasing trend of surface runoff in the mainstream and the observed alterations of the temporal and spatial distribution patterns were mainly due to the adverse impacts of human activities. Specifically, increasingly intensified water consumption for irrigation and the associated massive constructions of water conservancy projects were responsible for the decreasing trend of runoff in the mainstream. And, the decreasing trend has been severely jeopardizing the ecological security in the lower reaches. It is now unequivocally clear that water-use conflicts among different sectors and water-use competitions between upper and lower reaches are approaching to dangerous levels in TRB that is thus crying for implementing an integrated river basin management scheme.

Pollutant loads of surface runoff in Wuhan City Zoo, an urban tourist area.

PubMed

Zhao, Jian-wei; Shan, Bao-qing; Yin, Cheng-qing

2007-01-01

The pollutant loads of surface runoff in an urban tourist area have been investigated for two years in the Wuhan City Zoo, China. Eight sampling sites, including two woodlands, three animal yards, two roofs and one road, were selected for sampling and study. The results indicate that pollutants ranked in a predictable order of decreasing load (e.g. animal yard > roof > woodland > road), with animal yards acting as the key pollution source in the zoo. Pollutants were transported mainly by particulate form in runoff. Particulate nitrogen and particulate phosphorous accounted on average for 61%, 78% of total pollutant, respectively, over 13 monitored rainfall events. These results indicate the treatment practices should be implemented to improve particulate nutrient removal. Analysis of the M(V) curve indicate that no first flush effect existed in the surface runoff from pervious areas (e.g. woodland, animal ground yard), whereas a first flush effect was evident in runoff from impervious surfaces (e.g. animal cement yard, roof, road).

An R package for the design, analysis and operation of reservoir systems

NASA Astrophysics Data System (ADS)

Turner, Sean; Ng, Jia Yi; Galelli, Stefano

2016-04-01

We present a new R package - named "reservoir" - which has been designed for rapid and easy routing of runoff through storage. The package comprises well-established tools for capacity design (e.g., the sequent peak algorithm), performance analysis (storage-yield-reliability and reliability-resilience-vulnerability analysis) and release policy optimization (Stochastic Dynamic Programming). Operating rules can be optimized for water supply, flood control and amenity objectives, as well as for maximum hydropower production. Storage-depth-area relationships are in-built, allowing users to incorporate evaporation from the reservoir surface. We demonstrate the capabilities of the software for global studies using thousands of reservoirs from the Global Reservoir and Dam (GRanD) database fed by historical monthly inflow time series from a 0.5 degree gridded global runoff dataset. The package is freely available through the Comprehensive R Archive Network (CRAN).

Rainfall Driven Sorting of Soils and Manure in Beef Feedlot Pens, Implications for Steroid Hormone Transport

NASA Astrophysics Data System (ADS)

Bryson, R.; Harter, T.

2009-12-01

Previous research has documented elevated estrogenic and androgenic activity in surface waters receiving cattle feedlot effluent, while current research shows that significant concentrations of hydrophobic steroid hormones are transported in the solid phase of feedlot pen surface runoff. Accumulated manure in beef feedlot pens includes organic matter ranging from colloidal particles to partially digested feed, forming a complex soil-manure conglomerate at the pen surface. We hypothesized that the transport of solid phase particles in rainfall runoff on beef feedlots would be influenced but not limited by shield layer development. Soils and manure at a beef feedlot were evaluated before and after rainfall-runoff events to determine changes in soil composition and structure. Runoff samples were also collected during an hour of runoff and analyzed for suspended solids. Results indicate that rainfall actively sorts the soil and manure components through raindrop impact, depression storage and runoff. However, transport of solid phase constituents was found to be elevated throughout the hydrograph. This suggests that the surface shield layer conceptualization applied to other soils should be modified before application to the soil-manure conglomerate found in beef feedlot pens.

A model for phosphorus transformation and runoff loss for surface-applied manures.

PubMed

Vadas, P A; Gburek, W J; Sharpley, A N; Kleinman, P J A; Moore, P A; Cabrera, M L; Harmel, R D

2007-01-01

Agricultural P transport in runoff is an environmental concern. An important source of P runoff is surface-applied, unincorporated manures, but computer models used to assess P transport do not adequately simulate P release and transport from surface manures. We developed a model to address this limitation. The model operates on a daily basis and simulates manure application to the soil surface, letting 60% of manure P infiltrate into soil if manure slurry with less than 15% solids is applied. The model divides manure P into four pools, water-extractable inorganic and organic P, and stable inorganic and organic P. The model simulates manure dry matter decomposition, and manure stable P transformation to water-extractable P. Manure dry matter and P are assimilated into soil to simulate bioturbation. Water-extractable P is leached from manure when it rains, and a portion of leached P can be transferred to surface runoff. Eighty percent of manure P leached into soil by rain remains in the top 2 cm, while 20% leaches deeper. This 2-cm soil layer contributes P to runoff via desorption. We used data from field studies in Texas, Pennsylvania, Georgia, and Arkansas to build and validate the model. Validation results show the model accurately predicted cumulative P loads in runoff, reflecting successful simulation of the dynamics of manure dry matter, manure and soil P pools, and storm-event runoff P concentrations. Predicted runoff P concentrations were significantly related to (r2=0.57) but slightly less than measured concentrations. Our model thus represents an important modification for field or watershed scale models that assess P loss from manured soils.

Runoff losses of excreted chlortetracycline, sulfamethazine, and tylosin from surface-applied and soil-incorporated beef cattle feedlot manure.

PubMed

Amarakoon, Inoka D; Zvomuya, Francis; Cessna, Allan J; Degenhardt, Dani; Larney, Francis J; McAllister, Tim A

2014-03-01

Veterinary antimicrobials in land-applied manure can move to surface waters via rain or snowmelt runoff, thus increasing their dispersion in agro-environments. This study quantified losses of excreted chlortetracycline, sulfamethazine, and tylosin in simulated rain runoff from surface-applied and soil-incorporated beef cattle ( L.) feedlot manure (60 Mg ha, wet wt.). Antimicrobial concentrations in runoff generally reflected the corresponding concentrations in the manure. Soil incorporation of manure reduced the concentrations of chlortetracycline (from 75 to 12 μg L for a 1:1 mixture of chlortetracycline and sulfamethazine and from 43 to 17 μg L for chlortetracycline alone) and sulfamethazine (from 3.9 to 2.6 μg L) in runoff compared with surface application. However, there was no significant effect of manure application method on tylosin concentration (range, 0.02-0.06 μg L) in runoff. Mass losses, as a percent of the amount applied, for chlortetracycline and sulfamethazine appeared to be independent of their respective soil sorption coefficients. Mass losses of chlortetracycline were significantly reduced with soil incorporation of manure (from 6.5 to 1.7% when applied with sulfamethazine and from 6.5 to 3.5% when applied alone). Mass losses of sulfamethazine (4.8%) and tylosin (0.24%) in runoff were not affected by manure incorporation. Although our results confirm that cattle-excreted veterinary antimicrobials can be removed via surface runoff after field application, the magnitudes of chlortetracycline and sulfamethazine losses were reduced by soil incorporation of manure immediately after application. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Biological soil crust and disturbance controls on surface hydrology in a semi-arid ecosystem

USGS Publications Warehouse

Faist, Akasha M; Herrick, Jeffrey E.; Belnap, Jayne; Van Zee, Justin W; Barger, Nichole N

2017-01-01

Biological soil crust communities (biocrusts) play an important role in surface hydrologic processes in dryland ecosystems, and these processes may then be dramatically altered with soil surface disturbance. In this study, we examined biocrust hydrologic responses to disturbance at different developmental stages on sandy soils on the Colorado Plateau. Our results showed that all disturbance (trampling, scalping and trampling+scalping) of the early successional light cyanobacterial biocrusts generally reduced runoff. In contrast, trampling well-developed dark-cyano-lichen biocrusts increased runoff and sediment loss relative to intact controls. Scalping did not increase runoff, implying that soil aggregate structure was important to the infiltration process. Well-developed, intact dark biocrusts generally had lower runoff, low sediment loss, and highest aggregate stability whereas the less-developed light biocrusts were highest in runoff and sediment loss when compared to the controls. These results suggest the importance of maintaining the well-developed dark biocrusts, as they are beneficial for lowering runoff and reducing soil loss and redistribution on the landscape. These data also suggest that upslope patches of light biocrust may either support water transport to downslope vegetation patches or alternatively this runoff may place dark biocrust patches at risk of disruption and loss, given that light patches increase runoff and thus soil erosion potential.

Grain size distribution of road-deposited sediment and its contribution to heavy metal pollution in urban runoff in Beijing, China.

PubMed

Zhao, Hongtao; Li, Xuyong; Wang, Xiaomei; Tian, Di

2010-11-15

Pollutant washoff from road-deposited sediment (RDS) is an increasing problem associated with the rapid urbanization of China that results in urban non-point source pollution. Here, we analyzed the RDS grain size distribution and its potential impact on heavy metal pollution in urban runoff from impervious surfaces of urban villages, colleges and residences, and main traffic roads in the Haidian District, Beijing, China. RDS with smaller grain size had a higher metal concentration. Specifically, particles with the smallest grain size (<44 μm) had the highest metal concentration in most areas (unit: mg/kg): Cd 0.28-1.31, Cr 57.9-154, Cu 68.1-142, Ni 25.8-78.0, Pb 73.1-222 and Zn 264-664. Particles with smaller grain size (<250 μm) contributed more than 80% of the total metal loads in RDS washoff, while suspended solids with a grain size <44 μm in runoff water accounted for greater than 70% of the metal mass in the total suspended solids (TSS). The heavy metal content in the TSS was 2.21-6.52% of that in the RDS. These findings will facilitate our understanding of the importance of RDS grain size distribution in heavy metal pollution caused by urban storm runoff. Copyright © 2010 Elsevier B.V. All rights reserved.

Using insurance data to learn more about damages to buildings caused by surface runoff

NASA Astrophysics Data System (ADS)

Bernet, Daniel; Roethlisberger, Veronika; Prasuhn, Volker; Weingartner, Rolf

2015-04-01

In Switzerland, almost forty percent of total insurance loss due to natural hazards in the last two decades was caused by flooding. Those flood damages occurred not only within known inundation zones of water courses. Practitioners expect that roughly half of all flood damages lie outside of known inundation zones. In urban areas such damages may simply be caused by drainage system overload for instance. However, as several case studies show, natural and agricultural land play a major role in surface runoff formation leading to damages in rural and peri-urban areas. Although many damages are caused by surface runoff, the whole process chain including surface runoff formation, propagation through the landscape and damages to buildings is not well understood. Therefore, within the framework of a project, we focus our research on this relevant process. As such flash flood events have a very short response time and occur rather diffusely in the landscape, this process is very difficult to observe directly. Therefore indirect data sources with the potential to indicate spatial and temporal distributions of the process have to be used. For that matter, post-flood damage data may be a profitable source. Namely, insurance companies' damage claim records could provide a good picture about the spatial and temporal distributions of damages caused by surface runoff and, thus, about the process itself. In our research we analyze insurance data records of flood damage claims systematically to infer main drivers and influencing factors of surface runoff causing damages to buildings. To demonstrate the potential and drawbacks of using data from insurance companies in relation to damages caused by surface runoff, a case study is presented. A well-documented event with data from a public as well as a private insurance company is selected. The case study focuses on the differences of the datasets as well as the associated problems and advantages respectively. Furthermore, the analysis of the data, especially the crucial identification of damages caused by surface runoff opposed to damages caused by other processes such as riverine flooding, drainage system surcharges etc. are discussed.

The assessment of land use change impact on watersheds runoff using SWAT: case study of Urmia Lake in Iran

NASA Astrophysics Data System (ADS)

Jabbari, Anahita; Jarihani, Ben; Rezaie, Hossein

2015-04-01

Lake Urmia, long counted among the world's largest saltwater lakes, contains only 5% of the amount of water it did just 20 years ago. The decline is generally blamed on a combination of drought, increased water diversion for irrigated agriculture within the lake's watershed and land use mismanagement. It has been believed that land use changes in Lake Urmia basin is one of the most important factors in shrinkage of Urmia Lake in recent decades. Transforming the traditional agricultural practices (i.e., wheat) to the more water consuming practices (i.e., apple orchards) is one of the most important reasons increased agricultural water consumption in the watershed. In this study we assessed the effect of the land use changes of watershed in hydrological runoff processing in the Nazloo chai watershed, one of the most important river basins of the Urmia Lake basin. Actually the rapid and at the same time unreasonable transformations of land use in farm lands of Urmia lake sub basins, extremely has been raised the amount of blue water (surface or groundwater) consumption in watershed which leads to dramatic decrement of watershed runoff amounts. One of the most unfavorable consequences of land use change was changing the blue and green (rainwater insofar as it does not become runoff) water usage patterns in watershed, in addition to water use increment. The soil and water assessment tool (SWAT), one of the most important and reliable models which was used to model the rainfall runoff, has been used in current study. The land use maps were extracted from Landsat images archives for the most severe turning points in respect of land use change in the recent 30 years. After calibrating the model, several land use patterns of historical data were used in the model to produce the runoff. The results showed the strong relation between land use change and runoff reduction in the Lake Urmia basin.

Untreated runoff quality from roof and road surfaces in a low intensity rainfall climate.

PubMed

Charters, Frances J; Cochrane, Thomas A; O'Sullivan, Aisling D

2016-04-15

Sediment and heavy metals in stormwater runoff are key pollutants of urban waterways, and their presence in stormwater is driven by climatic factors such as rainfall intensity. This study describes the total suspended solids (TSS) and heavy metal concentrations found in runoff from four different urban surfaces within a residential/institutional catchment, in a climate where rainfall is typically of low intensity (<5.1mm·h(-1)). The results were compared to untreated runoff quality from a compilation of international studies. The road runoff had the highest TSS concentrations, while copper and galvanized roof runoff had the highest copper and zinc concentrations, respectively. Pollutant concentrations were found to be significantly different between surfaces; quantification and prediction of pollutant contributions from urban surfaces should thus take account of the different surface materials, instead of being aggregated into more generalized categories such as land use. The TSS and heavy metal concentrations were found to be at the low to medium end of ranges observed internationally, except for total copper and zinc concentrations generated by dissolution of copper and galvanized roofing material respectively; these concentrations were at least as high as those reported internationally. TSS wash-off from the roofs was seen to be a source-limited process, where all available TSS is washed off during the rain event despite the low intensity rainfall, whereas both road TSS and heavy metals wash-off from roof and road surfaces appeared to all be transport-limited and therefore some carryover of pollutants occurs between rain events. A first flush effect was seen from most surfaces for TSS, but not for heavy metals. This study demonstrates that in low intensity rainfall climates, quantification of untreated runoff quality from key individual surface types in a catchment are needed to enable development of targeted and appropriately sized stormwater treatment systems. Copyright © 2016 Elsevier B.V. All rights reserved.

Particle size distribution variance in untreated urban runoff and its implication on treatment selection.

PubMed

Charters, Frances J; Cochrane, Thomas A; O'Sullivan, Aisling D

2015-11-15

Understanding the particle size distribution (PSD) of sediment in urban runoff assists in the selection of appropriate treatment systems for sediment removal as systems vary in their ability to remove sediment across different particle size fractions. Variation in PSD in runoff from individual urban surfaces both during and across multiple rain events is not well understood and it may lead to performance uncertainty in treatment systems. Runoff PSDs in international literature were compiled to provide a comparative summary of PSDs from different urban surfaces. To further assess both intra-event and inter-event PSD variation, untreated runoff was collected from road, concrete roof, copper roof, and galvanized roof surfaces within an urban catchment exposed to the same rainfall conditions and analysed for PSD and total suspended solids (TSS). Road runoff had the highest TSS concentrations, while copper roofs had high initial TSS that reduced to very low levels under steady state conditions. Despite variation in TSS concentrations, the median particle diameter of the TSS was comparable across the surfaces. Intra-event variation was generally not significant, but substantial inter-event variation was observed, particularly for coarser road and concrete roof surfaces. PSD variation for each surface contributed to a wide range in predicted treatment performance and suggests that short-retention treatment devices carry a high performance risk of not being able to achieve adequate TSS removal across all rain events. Copyright © 2015 Elsevier Ltd. All rights reserved.

Approach and case-study of green infrastructure screening analysis for urban stormwater control.

PubMed

Eaton, Timothy T

2018-03-01

Urban stormwater control is an urgent concern in megacities where increased impervious surface has disrupted natural hydrology. Water managers are increasingly turning to more environmentally friendly ways of capturing stormwater, called Green Infrastructure (GI), to mitigate combined sewer overflow (CSO) that degrades local water quality. A rapid screening approach is described to evaluate how GI strategies can reduce the amount of stormwater runoff in a low-density residential watershed in New York City. Among multiple possible tools, the L-THIA LID online software package, using the SCS-CN method, was selected to estimate relative runoff reductions expected with different strategies in areas of different land uses in the watershed. Results are sensitive to the relative areas of different land uses, and show that bioretention and raingardens provide the maximum reduction (∼12%) in this largely residential watershed. Although commercial, industrial and high-density residential areas in the watershed are minor, larger runoff reductions from disconnection strategies and porous pavement in parking lots are also possible. Total stormwater reductions from various combinations of these strategies can reach 35-55% for individual land uses, and between 23% and 42% for the entire watershed. Copyright © 2017. Published by Elsevier Ltd.

Forms of phosphorus transfer in runoff under no-tillage in a soil treated with successive swine effluents applications.

PubMed

Lourenzi, Cledimar Rogério; Ceretta, Carlos Alberto; Tiecher, Tadeu Luis; Lorensini, Felipe; Cancian, Adriana; Stefanello, Lincon; Girotto, Eduardo; Vieira, Renan Costa Beber; Ferreira, Paulo Ademar Avelar; Brunetto, Gustavo

2015-04-01

Successive swine effluent applications can substantially increase the transfer of phosphorus (P) forms in runoff. The aim of this study was to evaluate P accumulation in the soil and transfer of P forms in surface runoff from a Hapludalf soil under no-tillage subjected to successive swine effluent applications. This research was carried out in the Agricultural Engineering Department of the Federal University of Santa Maria, Brazil, from 2004 to 2007, on a Typic Hapludalf soil. Swine effluent rates of 0, 20, 40, and 80 m3 ha(-1) were broadcast over the soil surface prior to sowing of different species in a crop rotation. Soil samples were collected in stratified layers, and the levels of available P were determined. Samples of water runoff from the soil surface were collected throughout the period, and the available, soluble, particulate, and total P were measured. Successive swine effluent applications led to increases in P availability, especially in the soil surface, and P migration through the soil profile. Transfer of P forms was closely associated with runoff, which is directly related to rainfall volume. Swine effluent applications also reduced surface runoff. These results show that in areas with successive swine effluent applications, practices that promote higher water infiltration into the soil are required, e.g., crop rotation and no-tillage system.

Total pollution effect of urban surface runoff.

PubMed

Luo, Hongbing; Luo, Lin; Huang, Gu; Liu, Ping; Li, Jingxian; Hu, Sheng; Wang, Fuxiang; Xu, Rui; Huang, Xiaoxue

2009-01-01

For pollution research with regard to urban surface runoff, most sampling strategies to date have focused on differences in land usage. With single land-use sampling, total surface runoff pollution effect cannot be evaluated unless every land usage spot is monitored. Through a new sampling strategy known as mixed stormwater sampling for a street community at discharge outlet adjacent to river, this study assessed the total urban surface runoff pollution effect caused by a variety of land uses and the pollutants washed off from the rain pipe system in the Futian River watershed in Shenzhen City of China. The water quality monitoring indices were COD (chemical oxygen demand), TSS (total suspend solid), TP (total phosphorus), TN (total nitrogen) and BOD (biochemical oxygen demand). The sums of total pollution loads discharged into the river for the four indices of COD, TSS, TN, and TP over all seven rainfall events were very different. The mathematical model for simulating total pollution loads was established from discharge outlet mixed stormwater sampling of total pollution loads on the basis of four parameters: rainfall intensity, total land area, impervious land area, and pervious land area. In order to treat surface runoff pollution, the values of MFF30 (mass first flush ratio) and FF30 (first 30% of runoff volume) can be considered as split-flow control criteria to obtain more effective and economical design of structural BMPs (best management practices) facilities.

Effects of soil surface roughness on interrill erosion processes and sediment particle size distribution

USDA-ARS?s Scientific Manuscript database

Soil surface roughness significantly impacts runoff and erosion under rainfall. Few previous studies on runoff generation focused on the effects of soil surface roughness on the sediment particle size distribution (PSD), which greatly affects interrill erosion and sedimentation processes. To address...

Contrasting effects of microbiotic crusts on runoff in desert surfaces

NASA Astrophysics Data System (ADS)

Kidron, Giora J.; Monger, H. Curtis; Vonshak, Ahuva; Conrod, William

2012-02-01

Microbiotic crusts (MCs) play an important role in surface hydrology by altering runoff yield. In order to study the crust's role on water redistribution, rainfall and runoff were measured during 1998-2000 at three sites within the northern Chihuahuan Desert, New Mexico, USA: the Sevilleta National Wildlife Refuge (SEV), the White Sands National Monument (WS), and the Jornada Experimental Range (JER). Whereas quartz and gypsum sand characterize the SEV and WS sites, respectively, both of which have high infiltration rates, silty alluvial deposits characterize the JER site. Runoff was measured in four pairs of 1.8-6.4 m 2 plots having MCs, one of which was scalped in each pair. No runoff was generated at WS, whether on the crusted or the scalped plots. Runoff was however generated at SEV and JER, being higher on the crusted plots at SEV and lower on the JER plots. The results were explained by the combined effect of (a) parent material and (b) the crust properties, such as species composition, microrelief (surface roughness) and exopolysaccharide (EPS) content (reflected in the ratio of carbohydrates to chlorophyll). Whereas the effective rainfall, the fines and the EPS content were found to explain runoff initiation, the effective rainfall and the crust microrelief were found to explain the amount of runoff at SEV and JER where runoff generation took place. The findings attest to the fundamental role of the parent material and the crust's species composition and properties on runoff and hence to the complex interactions and the variable effects that MCs have on dryland hydrology.

Runoff of pharmaceuticals and personal care products following application of biosolids to an agricultural field.

PubMed

Topp, Edward; Monteiro, Sara C; Beck, Andrew; Coelho, Bonnie Ball; Boxall, Alistair B A; Duenk, Peter W; Kleywegt, Sonya; Lapen, David R; Payne, Michael; Sabourin, Lyne; Li, Hongxia; Metcalfe, Chris D

2008-06-15

Municipal biosolids are a source of nutrients for crop production. Beneficial Management Practices (BMPs) can be used to minimize the risk of contamination of adjacent water resources with chemical or microbial agents that are of public or environmental health concern. In this field study, we applied biosolids slurry at a commercial rate using either subsurface injection or broadcast application followed by incorporation. Precipitation was simulated at 1, 3, 7, 22, 36 and 266 days post-application on 2 m(2) microplots to evaluate surface runoff of 9 model pharmaceuticals and personal care products (PPCPs), atenolol, carbamazepine, cotinine, gemfibrozil, naproxen, ibuprofen, acetaminophen, sulfamethoxazole and triclosan. In runoff from the injected plots, concentrations of the model PPCPs were generally below the limits of quantitation. In contrast, in the broadcast application treatment, the concentrations of atenolol, carbamazepine, cotinine, gemfibrozil, naproxen, sulfamethoxazole and triclosan on the day following application ranged from 70-1477 ng L(-1) in runoff and generally declined thereafter with first order kinetics. The total mass of PPCPs mobilized in surface runoff per m(2) of the field ranged from 0.63 microg for atenolol to 21.1 microg for ibuprofen. For ibuprofen and acetaminophen, concentrations in runoff first decreased and then increased, suggesting that these drugs were initially chemically or physically sequestered in the biosolids slurry, and subsequently released in the soil. Carbamazepine and triclosan were detected at low concentrations in a runoff event 266 days after broadcast application. Overall, this study showed that injection of biosolids slurry below the soil surface could effectively eliminate surface runoff of PPCPs.

Groundwater sapping processes, Western Desert, Egypt.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, W.; Arvidson, R.E.; Sultan, M.

1997-01-01

Depressions of the Western Desert of Egypt (specifically, Kharga, Farafra, and Kurkur regions) are mainly occupied by shales that are impermeable, but easily erodible by rainfall and runoff, whereas the surrounding plateaus are composed of limestones that are permeable and more resistant to fluvial erosion under semiarid to arid conditions. Scallop-shaped escarpment edges and stubby-looking channels that cut into the plateau units are suggestive of slumping of limestones by ground-water sapping at the limestone-shale interfaces, removal of slump blocks by weathering and fluvial erosion, and consequent scarp retreat. Spring-derived tufa deposits found near the limestone escarpments provide additional evidence formore » possible ground-water sapping during previous wet periods. A computer simulation model was developed to quantify the ground-water sapping processes, using a cellular automata algorithm with coupled surface runoff and ground-water flow for a permeable, resistant layer over an impermeable, friable unit. Erosion, deposition, slumping, and generation of spring-derived tufas were parametrically modeled. Simulations using geologically reasonable parameters demonstrate that relatively rapid erosion of the shales by surface runoff, ground-water sapping, and slumping of the limestones, and detailed control by hydraulic conductivity inhomogeneities associated with structures explain the depressions, escarpments, and associated landforms and deposits. Using episodic wet pulses, keyed by {delta}{sup 18}O deep-sea core record, the model produced tufa ages that are statistically consistent with the observed U/Th tufa ages. This result supports the hypothesis that northeastern African wet periods occurred during interglacial maxima. The {delta}{sup 18}O-forced model also replicates the decrease in fluvial and sapping activity over the past million years, as northeastern Africa became hyperarid. The model thus provides a promising predictive tool for studying long-term landform evolution that involves surface and subsurface processes and climatic change.« less

Hydrological heterogeneity in agricultural riparian buffer strips

NASA Astrophysics Data System (ADS)

Hénault-Ethier, Louise; Larocque, Marie; Perron, Rachel; Wiseman, Natalie; Labrecque, Michel

2017-03-01

Riparian buffer strips (RBS) may protect surface water and groundwater in agricultural settings, although their effectiveness, observed in field-scale studies, may not extend to a watershed scale. Hydrologically-controlled leaching plots have often shown RBS to be effective at buffering nutrients and pesticides, but uncontrolled field studies have sometimes suggested limited effectiveness. The limited RBS effectiveness may be explained by the spatiotemporal hydrological heterogeneity near non-irrigated fields. This hypothesis was tested in conventional corn and soy fields in the St. Lawrence Lowlands of southern Quebec (Canada), where spring melt brings heavy and rapid runoff, while summer months are hot and dry. One field with a mineral soil (Saint-Roch-de-l'Achigan) and another with an organic-rich soil (Boisbriand) were equipped with passive runoff collectors, suction cup lysimeters, and piezometers placed before and after a 3 m-wide RBS, and monitored from 2011 to 2014. Soil topography of the RBS was mapped to a 1 cm vertical precision and a 50 cm sampling grid. On average, surface runoff intersects the RBS perpendicularly, but is subject to substantial local heterogeneity. Groundwater saturates the root zones, but flows little at the time of snowmelt. Groundwater flow is not consistently perpendicular to the RBS, and may reverse, flowing from stream to field under low water flow regimes with stream-aquifer connectivity, thus affecting RBS effectiveness calculations. Groundwater flow direction can be influenced by stratigraphy, local soil hydraulic properties, and historical modification of the agricultural stream beds. Understanding the spatiotemporal heterogeneity of surface and groundwater flows is essential to correctly assess the effectiveness of RBS in intercepting agro-chemical pollution. The implicit assumption that water flows across vegetated RBS, from the field to the stream, should always be verified.

Surface water hydrology and the Greenland Ice Sheet

NASA Astrophysics Data System (ADS)

Smith, L. C.; Yang, K.; Pitcher, L. H.; Overstreet, B. T.; Chu, V. W.; Rennermalm, A. K.; Cooper, M. G.; Gleason, C. J.; Ryan, J.; Hubbard, A.; Tedesco, M.; Behar, A.

2016-12-01

Mass loss from the Greenland Ice Sheet now exceeds 260 Gt/year, raising global sea level by >0.7 mm annually. Approximately two-thirds of this total mass loss is now driven by negative ice sheet surface mass balance (SMB), attributed mainly to production and runoff of meltwater from the ice sheet surface. This new dominance of runoff as a driver of GrIS total mass loss will likely persist owing to anticipated further increases in surface melting, reduced meltwater storage in firn, and the waning importance of dynamical mass losses (ice calving) as the ice sheets retreat from their marine-terminating margins. It also creates the need and opportunity for integrative research pairing traditional surface water hydrology approaches with glaciology. As one example, we present a way to measure supraglacial "runoff" (i.e. specific discharge) at the supraglacial catchment scale ( 101-102 km2), using in situ measurements of supraglacial river discharge and high-resolution satellite/drone mapping of upstream catchment area. This approach, which is standard in terrestrial hydrology but novel for ice sheet science, enables independent verification and improvement of modeled SMB runoff estimates used to project sea level rise. Furthermore, because current SMB models do not consider the role of fluvial watershed processes operating on the ice surface, inclusion of even a simple surface routing model materially improves simulations of runoff delivered to moulins, the critical pathways for meltwater entry into the ice sheet. Incorporating principles of surface water hydrology and fluvial geomorphology and into glaciological models will thus aid estimates of Greenland meltwater runoff to the global ocean as well as connections to subglacial hydrology and ice sheet dynamics.

Enhanced terrestrial weathering/runoff and surface ocean carbonate production during the recovery stages of the Paleocene-Eocene thermal maximum

NASA Astrophysics Data System (ADS)

Kelly, D. Clay; Zachos, James C.; Bralower, Timothy J.; Schellenberg, Stephen A.

2005-12-01

The carbonate saturation profile of the oceans shoaled markedly during a transient global warming event known as the Paleocene-Eocene thermal maximum (PETM) (circa 55 Ma). The rapid release of large quantities of carbon into the ocean-atmosphere system is believed to have triggered this intense episode of dissolution along with a negative carbon isotope excursion (CIE). The brevity (120-220 kyr) of the PETM reflects the rapid enhancement of negative feedback mechanisms within Earth's exogenic carbon cycle that served the dual function of buffering ocean pH and reducing atmospheric greenhouse gas levels. Detailed study of the PETM stratigraphy from Ocean Drilling Program Site 690 (Weddell Sea) reveals that the CIE recovery period, which postdates the CIE onset by ˜80 kyr, is represented by an expanded (˜2.5 m thick) interval containing a unique planktic foraminiferal assemblage strongly diluted by coccolithophore carbonate. Collectively, the micropaleontological and sedimentological changes preserved within the CIE recovery interval reflect a transient state when ocean-atmosphere chemistry fostered prolific coccolithophore blooms that suppressed the local lysocline to relatively deeper depths. A prominent peak in the abundance of the clay mineral kaolinite is associated with the CIE recovery interval, indicating that continental weathering/runoff intensified at this time as well (Robert and Kennett, 1994). Such parallel stratigraphic changes are generally consonant with the hypothesis that enhanced continental weathering/runoff and carbonate precipitation helped sequester carbon during the PETM recovery period (e.g., Dickens et al., 1997; Zachos et al., 2005).

Simulating pesticide transport in urbanized catchments: a new spatially-distributed dynamic pesticide runoff model

NASA Astrophysics Data System (ADS)

Tang, Ting; Seuntjens, Piet; van Griensven, Ann; Bronders, Jan

2016-04-01

Urban areas can significantly contribute to pesticide contamination in surface water. However, pesticide behaviours in urban areas, particularly on hard surfaces, are far less studied than those in agricultural areas. Pesticide application on hard surfaces (e.g. roadsides and walkways) is of particular concern due to the high imperviousness and therefore high pesticide runoff potential. Experimental studies have shown that pesticide behaviours on and interactions with hard surfaces are important factors controlling the pesticide runoff potential, and therefore the magnitude and timing of peak concentrations in surface water. We conceptualized pesticide behaviours on hard surfaces and incorporated the conceptualization into a new pesticide runoff model. The pesticide runoff model was implemented in a catchment hydrological model WetSpa-Python (Water and Energy Transfer between Soil, Plants and Atmosphere, Python version). The conceptualization for pesticide processes on hard surfaces accounts for the differences in pesticide behaviour on different hard surfaces. Four parameters are used to describe the partitioning and wash-off of each pesticide on hard surfaces. We tested the conceptualization using experimental dataset for five pesticides on two types of hard surfaces, namely concrete and asphalt. The conceptualization gave good performance in accounting for the wash-off pattern for the modelled pesticides and surfaces, according to quantitative evaluations using the Nash-Sutcliffe efficiency and percent bias. The resulting pesticide runoff model WetSpa-PST (WetSpa for PeSTicides) can simulate pesticides and their metabolites at the catchment scale. Overall, it includes four groups of pesticide processes, namely pesticide application, pesticide interception by plant foliage, pesticide processes on land surfaces (including partitioning, degradation and wash-off on hard surface; partitioning, dissipation, infiltration and runoff in soil) and pesticide processes in depression storage (including degradation, infiltration and runoff). Processes on hard surfaces employs the conceptualization described in the paragraph above. The WetSpa-PST model can account for various spatial details of the urban features in a catchment, such as asphalt, concrete and roof areas. The distributed feature also allows users to input detailed pesticide application data of both non-point and point origins. Thanks to the Python modelling framework prototype used in the WetSpa-Python model, processes in the WetSpa-PST model can be simulated at different time steps depending on data availability and the characteristic temporal scale of each process. This helps to increase the computational accuracy during heavy rainfall events, especially for the associated fast transport of pesticides into surface water. Overall, the WetSpa-PST model has good potential in predicting effects of management options on pesticide releases from heavily urbanized catchments.

Combination of geochemical and hydrobiological tracers for the analysis of runoff generating processes in a lowland catchment

NASA Astrophysics Data System (ADS)

Faber, Claas; Wu, Naicheng; Ulrich, Uta; Fohrer, Nicola

2015-04-01

Since lowlands are characterised by flat topography and low hydraulic gradients, groundwater inflow has a large influence to streamflow generation in such catchments. In catchments with intense agricultural land use, artificial drainages are often another major contributor to streamflow. They shorten the soil passage and thus change the matter retention potential as well as runoff dynamics of a catchment. Contribution of surface runoff to streamflow is usually less important in volume. However, due to high concentrations of agrochemicals, surface runoff can constitute an important entry pathway into water bodies, especially if strong precipitation events coincide with fertilizer or pesticide application. The DFG funded project "Separating surface runoff from tile drainage flow in agricultural lowland catchments based on diatoms to improve modelled runoff components and phosphorous transport" investigates prevalent processes in this context in a 50 km² lowland catchment (Kielstau, Schleswig-Holstein, Germany) with the goal of improving existing models. End Member Mixing Analysis (EMMA) is used in the project to determine the relative importance of groundwater, tile drainage and surface runoff to streamflow at daily time steps. It became apparent that geochemical tracers are suitable for distinguishing surface runoff, but are weak for the separation of tile drainage and groundwater influence. We attribute this to the strong and complex interaction between soil water and shallow groundwater tables in the catchment. Recent studies (e.g. Pfister et al. 2011, Tauro et al. 2013) show the potential of diatoms as indicators for hydrological processes. Since we found diatoms to be suitable for the separation of tile drainage and stream samples (Wu et al., unpublished data) in our catchment, we are able to include diatom derived indices (e.g. density, species moisture indices, diversity indices) as traces in EMMA. Our results show that the inclusion of diatom data in the EMMA dataset improves the ability to distinguish tile drainage, groundwater and surface runoff influence to streamflow in our agriculturally dominated lowland catchment. Keywords: tile drainage, surface runoff, groundwater, hydrograph separation, EMMA, dia-toms, water quality, lowland catchments References: Pfister L, Wetzel CE, Martínez-Carreras N, Frentress J, Ector L, Hoffmann L, McDonnell JJ. 2011. Do diatoms run downhill? Using biodiversity of terrestrial and aquatic diatoms to identify hydrological connectivity between aquatic zones in Luxembourg. AGU Fall Meeting. Tauro F, Martínez-Carreras N, Wetzel CE, Hissler C, Barnich F, Frentress J, Ector L, Hoff-mann L, McDonnell JJ, Pfister L. 2013. Fluorescent diatoms as hydrological tracers: a proof of concept percolation experiment. EGU abstract, EGU2013-7687-4.

Simulation of Runoff Hydrograph on Soil Surfaces with Different Microtopography Using a Travel Time Method at the Plot Scale

PubMed Central

Zhao, Longshan; Wu, Faqi

2015-01-01

In this study, a simple travel time-based runoff model was proposed to simulate a runoff hydrograph on soil surfaces with different microtopographies. Three main parameters, i.e., rainfall intensity (I), mean flow velocity (v m) and ponding time of depression (t p), were inputted into this model. The soil surface was divided into numerous grid cells, and the flow length of each grid cell (l i) was then calculated from a digital elevation model (DEM). The flow velocity in each grid cell (v i) was derived from the upstream flow accumulation area using v m. The total flow travel time through each grid cell to the surface outlet was the sum of the sum of flow travel times along the flow path (i.e., the sum of l i/v i) and t p. The runoff rate at the slope outlet for each respective travel time was estimated by finding the sum of the rain rate from all contributing cells for all time intervals. The results show positive agreement between the measured and predicted runoff hydrographs. PMID:26103635

Simulation of Runoff Hydrograph on Soil Surfaces with Different Microtopography Using a Travel Time Method at the Plot Scale.

PubMed

Zhao, Longshan; Wu, Faqi

2015-01-01

In this study, a simple travel time-based runoff model was proposed to simulate a runoff hydrograph on soil surfaces with different microtopographies. Three main parameters, i.e., rainfall intensity (I), mean flow velocity (vm) and ponding time of depression (tp), were inputted into this model. The soil surface was divided into numerous grid cells, and the flow length of each grid cell (li) was then calculated from a digital elevation model (DEM). The flow velocity in each grid cell (vi) was derived from the upstream flow accumulation area using vm. The total flow travel time through each grid cell to the surface outlet was the sum of the sum of flow travel times along the flow path (i.e., the sum of li/vi) and tp. The runoff rate at the slope outlet for each respective travel time was estimated by finding the sum of the rain rate from all contributing cells for all time intervals. The results show positive agreement between the measured and predicted runoff hydrographs.

The use of simulated rainfall to study the discharge process and the influence factors of urban surface runoff pollution loads.

PubMed

Qinqin, Li; Qiao, Chen; Jiancai, Deng; Weiping, Hu

2015-01-01

An understanding of the characteristics of pollutants on impervious surfaces is essential to estimate pollution loads and to design methods to minimize the impacts of pollutants on the environment. In this study, simulated rainfall equipment was constructed to investigate the pollutant discharge process and the influence factors of urban surface runoff (USR). The results indicated that concentrations of total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (COD) appeared to be higher in the early period and then decreased gradually with rainfall duration until finally stabilized. The capacity and particle size of surface dust, rainfall intensity and urban surface slopes affected runoff pollution loads to a variable extent. The loads of TP, TN and COD showed a positive relationship with the surface dust capacity, whereas the maximum TSS load appeared when the surface dust was 0.0317 g·cm⁻². Smaller particle sizes (<0.125 mm) of surface dust generated high TN, TP and COD loads. Increases in rainfall intensity and surface slope enhanced the pollution carrying capacity of runoff, leading to higher pollution loads. Knowledge of the influence factors could assist in the management of USR pollution loads.

The Effects of Reduced Tillage on Phosphate Transport from Agricultural Land.

DTIC Science & Technology

1981-01-01

SOLUBLE INORGANIC I’IIOSPIORUS IN RUNOFF ................................................... 12 .F.ECT OF PHOSPHATE FERTILI ZATION ON LOSSES OF AVAILABLE...an reverse side if necessary end identifY by block number) Conservation Tillage Soil Loss Phosphorus Loss Surface Runoff 20 AMThAC? fCinf--- mbb iV...tillage (primarily no till) versus conventional tillage on surface runoff , soil loss and phosphorus loss. The data show that conservation tillage

Urban rainwater runoff quantity and quality - A potential endogenous resource in cities?

PubMed

Angrill, Sara; Petit-Boix, Anna; Morales-Pinzón, Tito; Josa, Alejandro; Rieradevall, Joan; Gabarrell, Xavier

2017-03-15

Rainwater harvesting might help to achieve self-sufficiency, but it must comply with health standards. We studied the runoff quantity and quality harvested from seven urban surfaces in a university campus in Barcelona according to their use (pedestrian or motorized mobility) and materials (concrete, asphalt and slabs). An experimental rainwater harvesting system was used to collect the runoff resulting from a set of rainfall events. We estimated the runoff coefficient and initial abstraction of each surface and analyzed the physicochemical and microbiological properties, and hydrocarbon and metal content of the samples. Rainfall intensity, surface material and state of conservation were essential parameters. Because of low rainfall intensity and surface degradation, the runoff coefficient was variable, with a minimum of 0.41. Concrete had the best quality, whereas weathering and particulate matter deposition led to worse quality in asphalt areas. Physicochemical runoff quality was outstanding when compared to superficial and underground water. Microorganisms were identified in the samples (>1 CFU/100 mL) and treatment is required to meet human consumption standards. Motorized traffic mostly affects the presence of metals such as zinc (31.7 μg/L). In the future, sustainable mobility patterns might result in improved rainwater quality standards. Copyright © 2016 Elsevier Ltd. All rights reserved.

Estimation of runoff mitigation by morphologically different cover crop root systems

NASA Astrophysics Data System (ADS)

Yu, Yang; Loiskandl, Willibald; Kaul, Hans-Peter; Himmelbauer, Margarita; Wei, Wei; Chen, Liding; Bodner, Gernot

2016-07-01

Hydrology is a major driver of biogeochemical processes underlying the distinct productivity of different biomes, including agricultural plantations. Understanding factors governing water fluxes in soil is therefore a key target for hydrological management. Our aim was to investigate changes in soil hydraulic conductivity driven by morphologically different root systems of cover crops and their impact on surface runoff. Root systems of twelve cover crop species were characterized and the corresponding hydraulic conductivity was measured by tension infiltrometry. Relations of root traits to Gardner's hydraulic conductivity function were determined and the impact on surface runoff was estimated using HYDRUS 2D. The species differed in both rooting density and root axes thickness, with legumes distinguished by coarser axes. Soil hydraulic conductivity was changed particularly in the plant row where roots are concentrated. Specific root length and median root radius were the best predictors for hydraulic conductivity changes. For an intensive rainfall simulation scenario up to 17% less rainfall was lost by surface runoff in case of the coarsely rooted legumes Melilotus officinalis and Lathyrus sativus, and the densely rooted Linum usitatissimum. Cover crops with coarse root axes and high rooting density enhance soil hydraulic conductivity and effectively reduce surface runoff. An appropriate functional root description can contribute to targeted cover crop selection for efficient runoff mitigation.

Estrogen Transport in Surface Runoff from Agricultural Fields Treated with Two Application Methods of Dairy Manure.

PubMed

Mina, Odette; Gall, Heather E; Saporito, Louis S; Kleinman, Peter J A

2016-11-01

This study compares two methods of dairy manure application-surface broadcast and shallow disk injection-on the fate and transport of natural estrogens in surface runoff from 12 field plots in central Pennsylvania. Ten natural surface runoff events were sampled over a 9-mo period after fall manure application. Results show that the range of estrogen concentrations observed in surface runoff from the broadcast plots was several orders of magnitude higher (>5000 ng L) than the concentrations in runoff from the shallow disk injection plots (<10 ng L). Additionally, the transport dynamics differed, with the majority of the estrogen loads from the surface broadcast plots occurring during the first rainfall event after application, whereas the majority of the loads from the shallow disk injection plots occurred more than 6 mo later during a hail storm event. Total estrogen loads were, on average, two orders of magnitude lower for shallow disk injection compared with surface broadcast. Independent of the method of manure application, 17α-estradiol and estrone were preserved in the field for as long as 9 mo after application. Overall, injection of manure shows promise in reducing the potential for off-site losses of hormones from manure-amended soils. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Scalability of grid- and subbasin-based land surface modeling approaches for hydrologic simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tesfa, Teklu K.; Ruby Leung, L.; Huang, Maoyi

2014-03-27

This paper investigates the relative merits of grid- and subbasin-based land surface modeling approaches for hydrologic simulations, with a focus on their scalability (i.e., abilities to perform consistently across a range of spatial resolutions) in simulating runoff generation. Simulations produced by the grid- and subbasin-based configurations of the Community Land Model (CLM) are compared at four spatial resolutions (0.125o, 0.25o, 0.5o and 1o) over the topographically diverse region of the U.S. Pacific Northwest. Using the 0.125o resolution simulation as the “reference”, statistical skill metrics are calculated and compared across simulations at 0.25o, 0.5o and 1o spatial resolutions of each modelingmore » approach at basin and topographic region levels. Results suggest significant scalability advantage for the subbasin-based approach compared to the grid-based approach for runoff generation. Basin level annual average relative errors of surface runoff at 0.25o, 0.5o, and 1o compared to 0.125o are 3%, 4%, and 6% for the subbasin-based configuration and 4%, 7%, and 11% for the grid-based configuration, respectively. The scalability advantages of the subbasin-based approach are more pronounced during winter/spring and over mountainous regions. The source of runoff scalability is found to be related to the scalability of major meteorological and land surface parameters of runoff generation. More specifically, the subbasin-based approach is more consistent across spatial scales than the grid-based approach in snowfall/rainfall partitioning, which is related to air temperature and surface elevation. Scalability of a topographic parameter used in the runoff parameterization also contributes to improved scalability of the rain driven saturated surface runoff component, particularly during winter. Hence this study demonstrates the importance of spatial structure for multi-scale modeling of hydrological processes, with implications to surface heat fluxes in coupled land-atmosphere modeling.« less

Ponds' water balance and runoff of endorheic watersheds in the Sahel

NASA Astrophysics Data System (ADS)

Gal, Laetitia; Grippa, Manuela; Kergoat, Laurent; Hiernaux, Pierre; Mougin, Eric; Peugeot, Christophe

2015-04-01

The Sahel has been characterized by a severe rainfall deficit since the mid-twentieth century, with extreme droughts in the early seventies and again in the early eighties. These droughts have strongly impacted ecosystems, water availability, fodder resources, and populations living in these areas. However, an increase of surface runoff has been observed during the same period, such as higher "summer discharge" of Sahelian's rivers generating local floods, and a general increase in pond's surface in pastoral areas of central and northern Sahel. This behavior, less rain but more surface runoff is generally referred to as the "Sahelian paradox". Various hypotheses have been put forward to explain this paradoxical situation. The leading role of increase in cropped areas, often cited for cultivated Sahel, does not hold for pastoral areas in central and northern Sahel. Processes such as degradation of vegetation subsequent to the most severe drought events, soils erosion and runoff concentration on shallow soils, which generate most of the water ending up in ponds, seem to play an important role. This still needs to be fully understood and quantified. Our study focuses on a model-based approach to better understand the hydrological changes that affected the Agoufou watershed (Gourma, Mali), typical of the central, non-cultivated Sahel. Like most of the Sahelian basins, the Agoufou watershed is ungauged. Therefore we used indirect data to provide the information required to validate a rainfall-runoff model approach. The pond volume was calculated by combining in-situ water level measurements with pond's surface estimations derived by remote sensing. Using the pond's water balance equation, the variations of pond volume combined to estimates of open water bodies' evaporation and infiltration determined an estimation for the runoff supplying the pond. This estimation highlights a spectacular runoff increase over the last sixty years on the Agoufou watershed. The runoff proxy derived for the Agoufou pond is used to evaluate results from the KINEROS2 model (KINematic runoff and EROSion). This model is specifically designed to simulate surface runoff in semi-arid watersheds. It describes the processes of runoff, infiltration and erosion by taking into account land cover and soil characteristics. We show that rain intensity, soil hydrological properties (hydraulic conductivity and Manning's roughness coefficient), contributing source area areas and land use-land cover were the major factors to take into account to correctly simulate runoff over the present period (2006-2010). This will help to simulate the past evolution of the Agoufou watershed and better understand the key mechanisms of the Sahelian paradox in non-cultivated Sahel. Finally, we will discuss the application of the SWOT and Sentinel-2 future satellites, which will provide water level and pond's surface, to obtain large-scale estimates of water balance in ungauged Sahelian basins.

[Research on stormwater runoff quality of mountain city by source area monitoring].

PubMed

Li, Li-Qing; Shan, Bao-Qing; Zhao, Jian-Wei; Guo, Shu-Gang; Gao, Yong

2012-10-01

Stormwater runoff samples were collected from 10 source areas in Mountain City, Chongqing, during five rain events in an attempt to investigate the characteristics of runoff quality and influencing factors. The outcomes are expected to offer practical guidance of sources control of urban runoff pollution. The results indicated that the stormwater runoff of Mountain City presented a strong first flush for almost all events and constituents. The runoff quality indices were also influenced by the rainfall intensity. The concentration of TSS, COD, TN and TP decreased as the rainfall intensity increased. The concentrations of COD and TP in stormwater runoff were highly correlated with TSS concentrations. Suspended solid matter were not only the main pollutant of stormwater runoff but also served as the vehicle for transport of organic matter and phosphorus. Organic matter and phosphorus in stormwatrer runoff were mainly bound to particles, whereas nitrogen was predominantly dissolved, with ammonia and nitrate. A significant difference of stormwater runoff quality was observed among the ten monitored source areas. The highest magnitude of urban stormwater runoff pollution was expected in the commercial area and the first trunk road, followed by the minor road, residential area, parking lot and roof. Urban surface function, traffic volume, population density, and street sweeping practice are the main factors determining spatial differentiation of urban surface runoff quality. Commercial area, the first trunk road and residential area with high population density are the critical sources areas of urban stormwater runoff pollution.

The Influence of Runoff and Surface Hydrology on Titan's Weather and Climate

NASA Astrophysics Data System (ADS)

Faulk, S.; Lora, J. M.; Mitchell, J.; Moon, S.

2017-12-01

Titan's surface liquid distribution has been shown by general circulation models (GCMs) to greatly influence the hydrological cycle, producing characteristic weather and seasonal climate patterns. Simulations from the Titan Atmospheric Model (TAM) with imposed polar methane "wetlands" reservoirs realistically produce observed cloud features and temperature profiles of Titan's atmosphere, whereas "aquaplanet" simulations with a global methane ocean are not as successful. In addition, wetlands simulations, unlike aquaplanet simulations, demonstrate strong correlations between extreme rainfall behavior and observed geomorphic features, indicating the influential role of precipitation in shaping Titan's surface. The wetlands configuration is, in part, motivated by Titan's large-scale topography featuring low-latitude highlands and high-latitude lowlands, with the implication being that methane may concentrate in the high-latitude lowlands by way of runoff and subsurface flow of a global or regional methane table. However, the extent to which topography controls the surface liquid distribution and thus impacts the global hydrological cycle by driving surface and subsurface flow is unclear. Here we present TAM simulations wherein the imposed wetlands reservoirs are replaced by a surface runoff scheme that allows surface liquid to self-consistently redistribute under the influence of topography. We discuss the impact of surface runoff on the surface liquid distribution over seasonal timescales and compare the resulting hydrological cycle to observed cloud and surface features, as well as to the hydrological cycles of the TAM wetlands and aquaplanet simulations. While still idealized, this more realistic representation of Titan's hydrology provides new insight into the complex interaction between Titan's atmosphere and surface, demonstrates the influence of surface runoff on Titan's global climate, and lays the groundwork for further surface hydrology developments in Titan GCMs, including infiltration and subsurface flow.

Silage storage runoff characterization: Annual nutrient loading rate and first flush analysis of bunder silos

USDA-ARS?s Scientific Manuscript database

Silage runoff produced during the preservation and storage of dairy forage in horizontal bunkers is a source of nutrient loss from the farmstead and a threat to surface water quality. This research evaluated the runoff characteristics from six dairy bunker facilities to determine runoff water qualit...

The effect of vegetation and soil texture on the nature of organics in runoff from a catchment supplying water for domestic consumption.

PubMed

Awad, John; van Leeuwen, John; Abate, Dawit; Pichler, Markus; Bestland, Erick; Chittleborough, David J; Fleming, Nigel; Cohen, Jonathan; Liffner, Joel; Drikas, Mary

2015-10-01

The influence of vegetation and soil texture on the concentration and character of dissolved organic matter (DOM) present in runoff from the surface and sub-surface of zero order catchments of the Myponga Reservoir-catchment (South Australia) was investigated to determine the impacts of catchment characteristics and land management practices on the quality of waters used for domestic supply. Catchments selected have distinct vegetative cover (grass, native vegetation or pine) and contrasting texture of the surface soil horizon (sand or clay loam/clay). Water samples were collected from three slope positions (upper, middle, and lower) at soil depths of ~30 cm and ~60 cm in addition to overland flows. Filtered (0.45 μm) water samples were analyzed for dissolved organic carbon (DOC) and UV-visible absorbance and by F-EEM and HPSEC with UV and fluorescence detection to characterize the DOM. Surface and sub-surface runoff from catchments with clay soils and native vegetation or grass had lower DOC concentrations and lower relative abundances of aromatic, humic-like and high molecular weight organics than runoff from sandy soils with these vegetative types. Sub-surface flows from two catchments with Pinus radiata had similar DOC concentrations and DOM character, regardless of marked variation in surface soil texture. Runoff from catchments under native vegetation and grass on clay soils resulted in lower DOC concentrations and hence would be expected to have lower coagulant demand in conventional treatment for potable water supply than runoff from corresponding sandy soil catchments. However, organics in runoff from clay catchments would be more difficult to remove by coagulation. Surface waters from the native vegetation and grass catchments were generally found to have higher relative abundance of organic compounds amenable to removal by coagulation compared with sub-surface waters. Biophysical and land management practices combine to have a marked influence on the quality of source water used for domestic supply. Copyright © 2015 Elsevier B.V. All rights reserved.

Pesticides on residential outdoor surfaces: environmental impacts and aquatic toxicity.

PubMed

Jiang, Weiying; Luo, Yuzhou; Conkle, Jeremy L; Li, Juying; Gan, Jay

2016-07-01

Pesticides are routinely applied to residential impervious outdoor surfaces for structural pest control. This residential usage has been linked to the occurrence of toxic levels of pesticides in urban water bodies. It is believed that run-off water transports particles that have sorbed hydrophobic pesticides. However, concentrations of particle-bound pesticides have not been directly measured on impervious surfaces, and the role of these particles as a source of contamination is unknown. Pesticides were detected in 99.4% of samples, with >75% of samples containing at least five pesticides. Assuming all particles were transferred with run-off, the run-off amount of pesticide during each rainfall would be >5 mg. We also used the US EPA Storm Water Management Model and estimated that 43 and 65% of the pesticides would be washed off during two rainfall events, with run-off concentrations ranging from 10.0 to 54.6 ng L(-1) and from 13.3 to 109.1 ng L(-1) respectively. The model-predicted pesticide run-off concentrations were similar to the levels monitored in urban run-off and sediments. Most (78%) particle samples contained aggregate toxicities above the Hyalella azteca LC50 . The results suggest that loose particles on residential impervious surfaces are not only carriers but also an important source of hydrophobic pesticides in urban run-off and contribute to downstream aquatic toxicities. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Stormwater runoff pollutant loading distributions and their correlation with rainfall and catchment characteristics in a rapidly industrialized city.

PubMed

Li, Dongya; Wan, Jinquan; Ma, Yongwen; Wang, Yan; Huang, Mingzhi; Chen, Yangmei

2015-01-01

Fast urbanization and industrialization in developing countries result in significant stormwater runoff pollution, due to drastic changes in land-use, from rural to urban. A three-year study on the stormwater runoff pollutant loading distributions of industrial, parking lot and mixed commercial and residential catchments was conducted in the Tongsha reservoir watershed of Dongguan city, a typical, rapidly industrialized urban area in China. This study presents the changes in concentration during rainfall events, event mean concentrations (EMCs) and event pollution loads per unit area (EPLs). The first flush criterion, namely the mass first flush ratio (MFFn), was used to identify the first flush effects. The impacts of rainfall and catchment characterization on EMCs and pollutant loads percentage transported by the first 40% of runoff volume (FF40) were evaluated. The results indicated that the pollutant wash-off process of runoff during the rainfall events has significant temporal and spatial variations. The mean rainfall intensity (I), the impervious rate (IMR) and max 5-min intensity (Imax5) are the critical parameters of EMCs, while Imax5, antecedent dry days (ADD) and rainfall depth (RD) are the critical parameters of FF40. Intercepting the first 40% of runoff volume can remove 55% of TSS load, 53% of COD load, 58% of TN load, and 61% of TP load, respectively, according to all the storm events. These results may be helpful in mitigating stormwater runoff pollution for many other urban areas in developing countries.

Stormwater Runoff Pollutant Loading Distributions and Their Correlation with Rainfall and Catchment Characteristics in a Rapidly Industrialized City

PubMed Central

Li, Dongya; Wan, Jinquan; Ma, Yongwen; Wang, Yan; Huang, Mingzhi; Chen, Yangmei

2015-01-01

Fast urbanization and industrialization in developing countries result in significant stormwater runoff pollution, due to drastic changes in land-use, from rural to urban. A three-year study on the stormwater runoff pollutant loading distributions of industrial, parking lot and mixed commercial and residential catchments was conducted in the Tongsha reservoir watershed of Dongguan city, a typical, rapidly industrialized urban area in China. This study presents the changes in concentration during rainfall events, event mean concentrations (EMCs) and event pollution loads per unit area (EPLs). The first flush criterion, namely the mass first flush ratio (MFFn), was used to identify the first flush effects. The impacts of rainfall and catchment characterization on EMCs and pollutant loads percentage transported by the first 40% of runoff volume (FF40) were evaluated. The results indicated that the pollutant wash-off process of runoff during the rainfall events has significant temporal and spatial variations. The mean rainfall intensity (I), the impervious rate (IMR) and max 5-min intensity (Imax5) are the critical parameters of EMCs, while Imax5, antecedent dry days (ADD) and rainfall depth (RD) are the critical parameters of FF40. Intercepting the first 40% of runoff volume can remove 55% of TSS load, 53% of COD load, 58% of TN load, and 61% of TP load, respectively, according to all the storm events. These results may be helpful in mitigating stormwater runoff pollution for many other urban areas in developing countries. PMID:25774922

Storm water runoff concentration matrix for urban areas.

PubMed

Göbel, P; Dierkes, C; Coldewey, W G

2007-04-01

The infrastructure (roads, sidewalk, commercial and residential structures) added during the land development and urbanisation process is designed to collect precipitation and convey it out of the watershed, typically in existing surface water channels, such as streams and rivers. The quality of surface water, seepage water and ground water is influenced by pollutants that collect on impervious surfaces and that are carried by urban storm water runoff. Heavy metals, e.g. lead (Pb), zinc (Zn), copper (Cu), cadmium (Cd), polycyclic aromatic hydrocarbons (PAH), mineral oil hydrocarbons (MOH) and readily soluble salts in runoff, contribute to the degradation of water. An intensive literature search on the distribution and concentration of the surface-dependent runoff water has been compiled. Concentration variations of several pollutants derived from different surfaces have been averaged. More than 300 references providing about 1300 data for different pollutants culminate in a representative concentration matrix consisting of medians and extreme values. This matrix can be applied to long-term valuations and numerical modelling of storm water treatment facilities.

Quantification of chemical transport processes from the soil to surface runoff.

PubMed

Tian, Kun; Huang, Chi-Hua; Wang, Guang-Qian; Fu, Xu-Dong; Parker, Gary

2013-01-01

There is a good conceptual understanding of the processes that govern chemical transport from the soil to surface runoff, but few studies have actually quantified these processes separately. Thus, we designed a laboratory flow cell and experimental procedures to quantify the chemical transport from soil to runoff water in the following individual processes: (i) convection with a vertical hydraulic gradient, (ii) convection via surface flow or the Bernoulli effect, (iii) diffusion, and (iv) soil loss. We applied different vertical hydraulic gradients by setting the flow cell to generate different seepage or drainage conditions. Our data confirmed the general form of the convection-diffusion equation. However, we now have additional quantitative data that describe the contribution of each individual chemical loading process in different surface runoff and soil hydrological conditions. The results of this study will be useful for enhancing our understanding of different geochemical processes in the surface soil mixing zone. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Surface models for coupled modelling of runoff and sewer flow in urban areas.

PubMed

Ettrich, N; Steiner, K; Thomas, M; Rothe, R

2005-01-01

Traditional methods fail for the purpose of simulating the complete flow process in urban areas as a consequence of heavy rainfall and as required by the European Standard EN-752 since the bi-directional coupling between sewer and surface is not properly handled. The new methodology, developed in the EUREKA-project RisUrSim, solves this problem by carrying out the runoff on the basis of shallow water equations solved on high-resolution surface grids. Exchange nodes between the sewer and the surface, like inlets and manholes, are located in the computational grid and water leaving the sewer in case of surcharge is further distributed on the surface. Dense topographical information is needed to build a model suitable for hydrodynamic runoff calculations; in urban areas, in addition, many line-shaped elements like houses, curbs, etc. guide the runoff of water and require polygonal input. Airborne data collection methods offer a great chance to economically gather densely sampled input data.

Runoff potentiality of a watershed through SCS and functional data analysis technique.

PubMed

Adham, M I; Shirazi, S M; Othman, F; Rahman, S; Yusop, Z; Ismail, Z

2014-01-01

Runoff potentiality of a watershed was assessed based on identifying curve number (CN), soil conservation service (SCS), and functional data analysis (FDA) techniques. Daily discrete rainfall data were collected from weather stations in the study area and analyzed through lowess method for smoothing curve. As runoff data represents a periodic pattern in each watershed, Fourier series was introduced to fit the smooth curve of eight watersheds. Seven terms of Fourier series were introduced for the watersheds 5 and 8, while 8 terms of Fourier series were used for the rest of the watersheds for the best fit of data. Bootstrapping smooth curve analysis reveals that watersheds 1, 2, 3, 6, 7, and 8 are with monthly mean runoffs of 29, 24, 22, 23, 26, and 27 mm, respectively, and these watersheds would likely contribute to surface runoff in the study area. The purpose of this study was to transform runoff data into a smooth curve for representing the surface runoff pattern and mean runoff of each watershed through statistical method. This study provides information of runoff potentiality of each watershed and also provides input data for hydrological modeling.

[Research on spatial differentiation of urban stormwater runoff quality by source area monitoring].

PubMed

Li, Li-Qing; Zhu, Ren-Xiao; Guo, Shu-Gang; Yin, Cheng-Qing

2010-12-01

Runoff samples were collected from 14 source areas in Hanyang district during four rain events in an attempt to investigate the spatial differentiation and influencing factors of urban stormwater runoff quality. The outcomes are expected to offer practical guidance in sources control of urban runoff pollution. The results revealed that particle-bound proportion of chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) in stormwater runoff were 58% +/- 17%, 65% +/- 13% and 92% +/- 6%, respectively. The fractions of ammonia, nitrate and dissolved organic nitrogen were homogeneous in dissolved nitrogen composition. Urban surface function, traffic volume, land use, population density, and street sweeping practice are the main factors determining spatial differentiation of urban surface runoff quality. The highest magnitude of urban stormwater runoff pollution was expected in the old urban residential area, followed by general residential with restaurants, commercial and transport area, new developments and green land. In addition, the magnitude of road stormwater runoff pollution is positively correlated to traffic volume, in the following order: the first trunk road > the second trunk road > minor road. Street sweeping and critical source areas controls should be implemented to mitigate the adverse effects of urban stormwater runoff on receive waters.

Runoff Potentiality of a Watershed through SCS and Functional Data Analysis Technique

PubMed Central

Adham, M. I.; Shirazi, S. M.; Othman, F.; Rahman, S.; Yusop, Z.; Ismail, Z.

2014-01-01

Runoff potentiality of a watershed was assessed based on identifying curve number (CN), soil conservation service (SCS), and functional data analysis (FDA) techniques. Daily discrete rainfall data were collected from weather stations in the study area and analyzed through lowess method for smoothing curve. As runoff data represents a periodic pattern in each watershed, Fourier series was introduced to fit the smooth curve of eight watersheds. Seven terms of Fourier series were introduced for the watersheds 5 and 8, while 8 terms of Fourier series were used for the rest of the watersheds for the best fit of data. Bootstrapping smooth curve analysis reveals that watersheds 1, 2, 3, 6, 7, and 8 are with monthly mean runoffs of 29, 24, 22, 23, 26, and 27 mm, respectively, and these watersheds would likely contribute to surface runoff in the study area. The purpose of this study was to transform runoff data into a smooth curve for representing the surface runoff pattern and mean runoff of each watershed through statistical method. This study provides information of runoff potentiality of each watershed and also provides input data for hydrological modeling. PMID:25152911

Effects of land use/land cover and climate changes on surface runoff in a semi-humid and semi-arid transition zone in northwest China

NASA Astrophysics Data System (ADS)

Yin, Jing; He, Fan; Jiu Xiong, Yu; Qiu, Guo Yu

2017-01-01

Water resources, which are considerably affected by land use/land cover (LULC) and climate changes, are a key limiting factor in highly vulnerable ecosystems in arid and semi-arid regions. The impacts of LULC and climate changes on water resources must be assessed in these areas. However, conflicting results regarding the effects of LULC and climate changes on runoff have been reported in relatively large basins, such as the Jinghe River basin (JRB), which is a typical catchment (> 45 000 km2) located in a semi-humid and arid transition zone on the central Loess Plateau, northwest China. In this study, we focused on quantifying both the combined and isolated impacts of LULC and climate changes on surface runoff. We hypothesized that under climatic warming and drying conditions, LULC changes, which are primarily caused by intensive human activities such as the Grain for Green Program, will considerably alter runoff in the JRB. The Soil and Water Assessment Tool (SWAT) was adopted to perform simulations. The simulated results indicated that although runoff increased very little between the 1970s and the 2000s due to the combined effects of LULC and climate changes, LULC and climate changes affected surface runoff differently in each decade, e.g., runoff increased with increased precipitation between the 1970s and the 1980s (precipitation contributed to 88 % of the runoff increase). Thereafter, runoff decreased and was increasingly influenced by LULC changes, which contributed to 44 % of the runoff changes between the 1980s and 1990s and 71 % of the runoff changes between the 1990s and 2000s. Our findings revealed that large-scale LULC under the Grain for Green Program has had an important effect on the hydrological cycle since the late 1990s. Additionally, the conflicting findings regarding the effects of LULC and climate changes on runoff in relatively large basins are likely caused by uncertainties in hydrological simulations.

The genetic structure of the chloride ion runoff on the example of karst and non-karst geosystems of Arkhangelsk oblast

NASA Astrophysics Data System (ADS)

Khayrullina, D. N.; Kurzhanova, A. A.

2018-01-01

This paper deals with the estimate the structure of the chloride ion runoff from the karst (on the example of the Sula river basin) and non-karst (on the example of the Vaga river basin) geosystems of Arkhangelsk oblast. The contribution of the surface component predominates in the structure of the chloride ion runoff.For example, the input of surface ion runoff is 49% (for the Sula river basin), 55% (for the Vaga river basin). In time aspect the highest values of variability of the components of the chloride ion runoff are noted for karst geosystems and vary from 38.5% to 55.4% and from 24.7% to 42.9% - for non-karst geosystems.Finally, there is prevalence of the local factors influence because the atmospheric component decreases while ion runoff increases.

Phosphorus runoff from waste water treatment biosolids and poultry litter applied to agricultural soils.

PubMed

White, John W; Coale, Frank J; Sims, J Thomas; Shober, Amy L

2010-01-01

Differences in the properties of organic phosphorus (P) sources, particularly those that undergo treatment to reduce soluble P, can affect soil P solubility and P transport in surface runoff. This 2-yr field study investigated soil P solubility and runoff P losses from two agricultural soils in the Mid-Atlantic region after land application of biosolids derived from different waste water treatment processes and poultry litter. Phosphorus speciation in the biosolids and poultry litter differed due to treatment processes and significantly altered soil P solubility and dissolved reactive P (DRP) and bioavailable P (FeO-P) concentrations in surface runoff. Runoff total P (TP) concentrations were closely related to sediment transport. Initial runoff DRP and FeO-P concentrations varied among the different biosolids and poultry litter applied. Over time, as sediment transport declined and DRP concentrations became an increasingly important component of runoff FeO-P and TP, total runoff P was more strongly influenced by the type of biosolids applied. Throughout the study, application of lime-stabilized biosolids and poultry litter increased concentrations of soil-soluble P, readily desorbable P, and soil P saturation, resulting in increased DRP and FeO-P concentrations in runoff. Land application of biosolids generated from waste water treatment processes that used amendments to reduce P solubility (e.g., FeCl(3)) did not increase soil P saturation and reduced the potential for DRP and FeO-P transport in surface runoff. These results illustrate the importance of waste water treatment plant process and determination of specific P source coefficients to account for differential P availability among organic P sources.

Effects of cattle manure on erosion rates and runoff water pollution by faecal coliforms.

PubMed

Ramos, M C; Quinton, J N; Tyrrel, S F

2006-01-01

The large quantities of slurry and manure that are produced annually in many areas in which cattle are raised could be an important source of organic matter and nutrients for agriculture. However, the benefits of waste recycling may be partially offset by the risk of water pollution associated with runoff from the fields to which slurry or manure has been applied. In this paper, the effects of cattle manure application on soil erosion rates and runoff and on surface water pollution by faecal coliforms are analysed. Rainfall simulations at a rate of 70 mm h(-1) were conducted in a sandy loam soil packed into soil flumes (2.5m long x 1m wide) at a bulk density of 1400 kg m(-3), with and without cattle slurry manure applied on the surface. For each simulation, sediment and runoff rates were analysed and in those simulations with applied slurry, presumptive faecal coliform (PFC) concentrations in the runoff were evaluated. The application of slurry on the soil surface appeared to have a protective effect on the soils, reducing soil detachment by up to 70% but increasing runoff volume by up to 30%. This practice implies an important source of pollution for surface waters especially if rainfall takes place within a short period after application. The concentrations of micro-organisms (presumptive faecal coliforms (PFCs)) found in water runoff ranged from 1.9 x 10(4) to 1.1 x 10(6) PFC 100mL(-1), depending on the initial concentration in the slurry, and they were particularly high during the first phases of the rainfall event. The result indicates a strong relationship between the faecal coliforms transported by runoff and the organic matter in the sediment.

Prediction of Estrogen Runoff and Transport Driven by Rainfalls from Swine Spray Fields

NASA Astrophysics Data System (ADS)

Lee, B.; Reckhow, K. H.; Kullman, S. W.

2010-12-01

Animal waste-borne steroidal hormones, which are referred to as natural steroidal estrogens, are recognized pollutants to surface water systems. Steroidal estrogens exhibit strong potency, even at very low concentrations, as endocrine disrupting chemicals on aquatic organisms. In North Carolina, the swine concentrated animal feeding operations (CAFOs) have been a major source for the release of estrogens to watersheds. Release is a direct result of the land application of the generated waste as an organic fertilizer. However, data regarding the estrogen loss and transport through the surface runoff and soil erosion to the water bodies after the spray-fields application has been up till now very limited. We have developed a decision support tool that can help predict and ultimately manage the potential mobilization and transport of estrogens from CAFOs, through the processes of surface runoff transport and sediment loss, into adjacent water bodies. Our decision support tool was built using a dynamic Bayesian Network (DBN) framework. The developed DBN model integrates the processes of a sediment loss and a surface runoff by using the modified universal soil loss equation (MUSLE) and the SCS-CN curve runoff models. Estrogen mobility is assessed as a function of rainfall intensity and land use management with consideration to the temporal distribution of both. The DBN is used to model the estrogen concentration in the runoff process, to determine the degree of off-site movement of estrogens, and to verify the potential environmental significance of the estrogen inputs into the stream. We believe that our modeling framework is particularly useful for use in field situations where estrogen runoff data are not available or are scarce. The DBN model also provides a means to handle the uncertainties of mathematical sediment and runoff models as a dynamic probability model.

Effects of rainfall and surface flow on chemical diffusion from soil to runoff water

USDA-ARS?s Scientific Manuscript database

Although basic processes of diffusion and convection have been used to quantify chemical transport from soil to surface runoff, there are little research results actually showing how these processes were affected by rainfall and surface flow. We developed a laboratory flow cell and a sequence of exp...

Nutrient Loss in Runoff from Turf: Effect on Surface Water Quality

USDA-ARS?s Scientific Manuscript database

Excess nutrients in surface waters may result in enhanced algal blooms and plant growth that can lead to eutrophication and a decline in water quality. The applicatin of fertilizer to golf courses may be a source of nutrients to surface waters. Runoff studies were conducted to measure applied nitrog...

Vegetated Treatment Systems for Removing Contaminants Associated with Surface Water Toxicity in Agriculture and Urban Runoff.

PubMed

Anderson, Brian S; Phillips, Bryn M; Voorhees, Jennifer P; Cahn, Michael

2017-05-15

Urban stormwater and agriculture irrigation runoff contain a complex mixture of contaminants that are often toxic to adjacent receiving waters. Runoff may be treated with simple systems designed to promote sorption of contaminants to vegetation and soils and promote infiltration. Two example systems are described: a bioswale treatment system for urban stormwater treatment, and a vegetated drainage ditch for treating agriculture irrigation runoff. Both have similar attributes that reduce contaminant loading in runoff: vegetation that results in sorption of the contaminants to the soil and plant surfaces, and water infiltration. These systems may also include the integration of granulated activated carbon as a polishing step to remove residual contaminants. Implementation of these systems in agriculture and urban watersheds requires system monitoring to verify treatment efficacy. This includes chemical monitoring for specific contaminants responsible for toxicity. The current paper emphasizes monitoring of current use pesticides since these are responsible for surface water toxicity to aquatic invertebrates.

Using diatoms, hydrochemical and stable isotope tracers to infer runoff generation processes

NASA Astrophysics Data System (ADS)

Martínez-Carreras, N.; Wetzel, C. E.; Frentress, J.; Hlúbiková, D.; Ector, L.; McDonnell, J. J.; Hoffmann, L.; Pfister, L.

2012-04-01

Imaginative techniques are needed to improve our understanding of runoff generation processes. In this context, the hydrological community calls to cut across disciplines looking for new and exciting advances in knowledge. In this study, hydrologists and ecologists have worked together to use not only hydrochemical and stable isotope tracers, but also diatoms to infer runoff generation processes. Diatoms, one of the most common and divers algal group, can be easily transported by flowing water due to their small size (~10-200 μm). They are present in most terrestrial habitats and their diversified species distributions are largely controlled by physico-geographical factors (e.g. light, temperature, pH and moisture). Thus, hydrological systems largely control diatom species community composition and distribution. This study was conducted in the schistose Weierbach catchment (0.45 km2, NW Luxembourg). Its runoff regime is characterised by seasonal variation and a delayed shallow groundwater component originating from a saprolite zone. The catchment was instrumented with piezometers, suction cups, an automatic streamwater sampler, a sequential rainfall sampler, and soil moisture and temperature sensors. Samples collected bi-weekly and during storm runoff events allowed the characterisation of the different end-members. Chemical and isotopic hydrograph separations of stream discharge were used to determine not only the geographic sources of water, but also the fractions of old and new water contributing to streamflow. Diatoms intra-storm variability was also analysed and samples of diatoms from various terrestrial and subaerial substrates (bryophytes, litter and leaves), as well as from aquatic habitats (epilithon, epipelon and drift samples) were regularly collected. Diatoms were then used to constrain assumptions and to confirm or reject the hypothesis of existing surface runoff during rainfall-runoff events and to document the intermittent character of hydrological connectivity between upland, riparian and aquatic zones. As an advantage, diatoms do not seem to be subject to some inherent limitations of the classical tracer-based hydrograph separation techniques, such as unrealistic mixing assumptions, unstable end-member solutions and temporally varying input concentrations. Results suggested a substantial contribution of soil water during winter events in the Weierbach catchment, whereas groundwater played a more significant role during summer events. Even though overland flow remained insignificant during most of the sampled events, terrestrial diatom abundance increased with precipitation in all sampled events suggesting a rapid connectivity between soil surface and stream water. We hypothesise the mobilization and flushing away of terrestrial diatoms through a subsurface network of macropores in the shallow soils.

Runoff simulations from the Greenland ice sheet at Kangerlussuaq from 2006-2007 to 2007/08. West Greenland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mernild, Sebastian Haugard; Hasholt, Bent; Van Den Broeke, Michiel

2009-01-01

This study focuses on runoff from a large sector of the Greenland Ice Sheet (GrIS) - the Kangerlussuaq drainage area, West Greenland - for the runoff observation period 2006/07 to 2007/08. SnowModel, a state-of-the-art snow-evolution modeling system, was used to simulate winter accumulation and summer ablation processes, including runoff. Independent in situ end-of-winter snow depth and high-resolution runoff observations were used for validation of simulated accumulation and ablation processes. Runoff was modeled on both daily and hourly time steps, filling a data gap of runoff exiting part of the GrIS. Using hourly meteorological driving data instead of smoothed daily-averaged datamore » produced more realistic meteorological conditions in relation to snow and melt threshold surface processes, and produced 6-17% higher annual cumulative runoff. The simulated runoff series yielded useful insights into the present conditions of inter-seasonal and inter-annual variability of Kangerlussuaq runoff, and provided an acceptable degree of agreement between simulated and observed runoff. The simulated spatial runoff distributions, in some areas of the GrIS terminus, were as high as 2,750 mm w.eq. of runoff for 2006/07, while only 900 mm w.eq was simulated for 2007/08. The simulated total runoff from Kangerlussuaq was 1.9 km{sup 3} for 2006/07 and 1.2 km{sup 3} for 2007/08, indicating a reduction of 35-40% caused by the climate conditions and changes in the GrIS freshwater storage. The reduction in runoff from 2006/07 to 2007/08 occurred simultaneously with the reduction in the overall pattern of satellite-derived GrIS surface melt from 2007 to 2008.« less

Factors affecting phosphorus transport at a conventionally-farmed site in Lancaster County, Pennsylvania, 1992-95

USGS Publications Warehouse

Galeone, Daniel G.

1996-01-01

The U.S. Geological Survey and the Bureau of Land and Water Conservation of the Pennsylvania Department of Environmental Protection conducted a cooperative study to determine the effects of manure application and antecedent soil-phosphorus concentrations on the transport of phosphorus from the soil of a typical farm site in Lancaster County, Pa., from September 1992 to March 1995. The relation between concentrations of soil phosphorus and phosphorus transport needs to be identified because excessive phosphorus concentrations in surface-water bodies promote eutrophication.The objective of the study was to quantify and determine the significance of chemical, physical, and hydrologic factors that affected phosphorus transport. Three study plots less than 1 acre in size were tilled and planted in silage corn. Phosphorus in the form of liquid swine and dairy manure was injected to a depth of 6-8 inches on two of the three study plots in May 1993 and May 1994. Plot 1 received no inputs of phosphorus from manure while plots 2 and 3 received an average of 56 and 126 kilograms of phosphorus per acre, respectively, from the two manure applications. No other fertilizer was applied to any of the study plots. From March 30, 1993, through December 31, 1993, and March 10, 1994, through August 31, 1994 (the study period), phosphorus and selected cations were measured in precipitation, manure, soil, surface runoff, subsurface flow (at 18 inches below land surface), and corn plants before harvest. All storm events that yielded surface runoff and subsurface flow were sampled. Surface runoff was analyzed for dissolved (filtered through a 0.45-micron filter) and total concentrations. Subsurface flow was only analyzed for dissolved constituents. Laboratory soil-flask experiments and geochemical modeling were conducted to determine the maximum phosphate retention capacity of sampled soils after manure applications and primary mineralogic controls in the soils that affect phosphate equilibrium processes.Physical characteristics, such as particle-size distributions in soil, the suspended sediment and particle-size distribution in surface runoff, and surface topography, were quantified. Hydrologic characteristics, such as precipitation intensity and duration, volumes of surface runoff, and infiltration rates of soil, were also monitored during the study period. Volumes of surface runoff differed by plot.Volumes of surface runoff measured during the study period from plots 1 (0.43 acres), 2 (0.23 acres), and 3 (0.28 acres) were 350,000, 350,000, and 750,000 liters per acre, respectively. About 90 percent of the volume of surface runoff occurred after October 1993 because of the lack of intense precipitation from March 30, 1993, through November 30, 1993. For any one precipitation amount, volumes of surface runoff increased with an increase in the maximum intensity of precipitation and decreased with an increase in storm duration. The significantly higher volume of surface runoff for plot 3 relative to plots 1 and 2 was probably caused by lower infiltration rates on plot 3.Soil concentrations of plant-available phosphorus (PAP) for each study plot were high (31-60 parts per million) to excessive (greater than 60 parts per million) for each depth interval (0-6, 6-12, and 12- 24 inches) and sampling period except for some samples collected at depths of 12-24 inches. The high levels of PAP before manure applications made it difficult to detect any changes in the concentration of soil PAP caused by manure applications. Manure applications to the study area prior to this study resulted in relatively high concentrations of soil PAP; however, the manure applications to plot 3 during the study period did cause an increase in the soil concentration of PAP after the second manure application. The percentages of total phosphorus in plant-available and inorganic forms were about 5 and 80 percent, respectively, in the 0-24--inch depth interval of soil on the study plots. Concentrations of total phosphorus on sand, silt, and clay particles from soil were 700, 1,000, and 3,400 parts per million, respectively. About 70 percent of the total mass of phosphorus in soil to a depth of 24 inches was associated with silt and clay particles.Soil-flask experiments indicated that soils from the study plots were not saturated with respect to phosphorus. Soils had the capacity to retain 694 to 1,160 milligrams of phosphorus per kilogram of soil. The measured retention capacity probably exceeded the actual retention capacity of soil because laboratory conditions optimized the contact time between soil and test solutions.Geochemical modeling indicated that the primary mineralogical controls on the concentration of dissolved phosphorus in surface runoff and subsurface flow were aluminum and iron oxides and strengite (if it exists). Aluminum and iron oxides bind phosphate in solution and strengite is an iron-phosphate mineral. The mineralization of organic phosphorus into dissolved inorganic forms could also supply phosphorus to surface runoff and subsurface flow.Phosphorus inputs to the plots during the study period were from precipitation and manure. Phosphorus inputs from precipitation were negligible. The loads of phosphorus to the plots from manure applications in May 1993 and May 1994 were 112 and 251 kilograms per acre for plots 2 and 3, respectively; about 60 percent of the load occurred in 1994.Phosphorus outputs in surface runoff differed between study plots. The cumulative yields of total phosphorus during the study period for plots 1, 2, and 3 were 1.12, 1.24, and 1.69 kilograms per acre, respectively. Differences between plots were primarily evident for dissolved yields of phosphorus. The percentage of the total phosphorus output in surface runoff that was in the dissolved phase varied from 6 percent for plot 1 to 26 percent for plot 3.The cumulative yields of dissolved phosphorus from plots 2 and 3 were 135 and 500 percent greater, respectively, than the dissolved yield from plot 1. Even though volumes of surface runoff were different on the plots, the primary cause of the difference between plots in the yield of dissolved phosphorus in surface runoff was differences in the concentration of dissolved phosphorus. After the second manure application, concentrations of dissolved phosphorus in surface runoff on plots 2 and 3 were significantly higher than the concentration for plot 1.An increase in the concentration of dissolved phosphorus in subsurface flow from plots 2 and 3 was measured after manure applications. The mean concentrations of dissolved phosphorus in subsurface flow after the first manure application were 0.29, 0.57, and 1.45 milligrams per liter of phosphorus for plots 1, 2, and 3, respectively.The loss of dissolved phosphorus in surface runoff was related to the soil concentration of PAP. The model relating dissolved phosphorus in surface runoff to soil PAP indicated that concentrations of dissolved phosphorus in surface runoff would exceed 0.1 milligram per liter if soil concentrations of PAP exceeded 9 parts per million; this PAP concentration was exceeded by each study plot. Over 50 percent of the variation of dissolved phosphorus in surface runoff was explained by soil concentrations of PAP in the 0-6-inch depth interval.The loss of suspended phosphorus in surface runoff was primarily affected by the particle-size distribution of suspended sediment in surface runoff. Surface runoff was enriched with fines relative to the soil matrix. Generally, over 90 percent of sediment in runoff was comprised of silt and clay particles; only 50-60 percent of particle sizes from the intact soil matrix were in the silt- to clay-size range. Concentrations of suspended phosphorus in surface runoff were not significantly related to soil concentrations of total phosphorus in the 0-6-inch depth interval.Concentrations of dissolved phosphorus in subsurface flow were also related to soil concentrations of PAP. The relation indicated that dissolved concentrations of phosphorus in subsurface flow would exceed 0.1 milligram per liter if soil concentrations of PAP in the 0-6-inch depth interval of soil were greater than 49 parts per million; this PAP concentration was exceeded by each study plot.The significant relation of high concentrations of dissolved phosphorus in water to soil concentrations of PAP indicated that soils with comparable concentrations of soil PAP would be potential sources of dissolved phosphorus to surface water and subsurface water tables. The percentage of the total phosphorus lost from a system in the dissolved form increased as soil concentrations of PAP increased. This indicates that best-management practices to reduce phosphorus losses from this system not only need to target suspended forms of phosphorus but also dissolved forms. Practices aimed at reducing the loss of dissolved phosphorus from the system increase in importance with an increase in soil concentrations of PAP.

Simulation and assessment of urbanization impacts on runoff metrics: insights from landuse changes

NASA Astrophysics Data System (ADS)

Zhang, Yongyong; Xia, Jun; Yu, Jingjie; Randall, Mark; Zhang, Yichi; Zhao, Tongtiegang; Pan, Xingyao; Zhai, Xiaoyan; Shao, Quanxi

2018-05-01

Urbanization-induced landuse changes alter runoff regimes in complex ways. In this study, a detailed investigation of the urbanization impacts on runoff regimes is provided by using multiple runoff metrics and with consideration of landuse dynamics. A catchment hydrological model is modified by coupling a simplified flow routing module of the urban drainage system and landuse dynamics to improve long-term urban runoff simulations. Moreover, multivariate statistical approach is adopted to mine the spatial variations of runoff metrics so as to further identify critical impact factors of landuse changes. The Qing River catchment as a peri-urban catchment in the Beijing metropolitan area is selected as our study region. Results show that: (1) the dryland agriculture is decreased from 13.9% to 1.5% of the total catchment area in the years 2000-2015, while the percentages of impervious surface, forest and grass are increased from 63.5% to 72.4%, 13.5% to 16.6% and 5.1% to 6.5%, respectively. The most dramatic landuse changes occur in the middle and downstream regions; (2) The combined landuse changes do not alter the average flow metrics obviously at the catchment outlet, but slightly increase the high flow metrics, particularly the extreme high flows; (3) The impacts on runoff metrics in the sub-catchments are more obvious than those at the catchment outlet. For the average flow metrics, the most impacted metric is the runoff depth in the dry season (October ∼ May) with a relative change from -10.9% to 11.6%, and the critical impact factors are the impervious surface and grass. For the high flow metrics, the extreme high flow depth is increased most significantly with a relative change from -0.6% to 10.5%, and the critical impact factors are the impervious surface and dryland agriculture; (4) The runoff depth metrics in the sub-catchments are increased because of the landuse changes from dryland agriculture to impervious surface, but are decreased because of the landuse changes from dryland agriculture or impervious surface to grass or forest. The results of this study provide useful information for urban planning such as Sponge City design.

Urbanization and climate change implications in flood risk management: Developing an efficient decision support system for flood susceptibility mapping.

PubMed

Mahmoud, Shereif H; Gan, Thian Yew

2018-04-26

The effects of urbanization and climate change impact to the flood risk of two governorates in Egypt were analyzed. Non-parametric change point and trend detection algorithms were applied to the annual rainfall, rainfall anomaly, and temperature anomaly of both study sites. Next, change points and trends of the annual and monthly surface runoff data generated by the Curve Number method over 1948-2014 were also analyzed to detect the effects of urbanization on the surface runoff. Lastly, a GIS decision support system was developed to delineate flood susceptibility zones for the two governorates. The significant decline in annual rainfall and rainfall anomaly after 1994 at 8.96 and 15.3 mm/decade respectively was likely due to climate change impact, especially significant warming trend since 1976 at 0.16 °C/decade, though that could partly be attributed to rapid urbanization. Since 1970, effects of urbanization to flood risk are clear, because despite a decline in rainfall, the annual surface runoff and runoff anomaly show positive trends of 12.7 and of 14.39 mm/decade, respectively. Eleven flood contributing factors have been identified and used in mapping flood susceptibility zones of both sites. In the El-Beheira governorate, 9.2%, 17.9%, 32.3%, 28.3% and 12.3% of its area are categorized as very high, high, moderate, low and very low susceptibility to flooding, respectively. Similarly, in Alexandria governorate, 15.9%, 33.5%, 41%, 8.8% and 0.8% of its area are categorized as very high, high, moderate, low and very low susceptibility to flooding, respectively. Very high and high susceptible zones are located in the northern, northwestern and northeastern parts of the Beheira governorates, and in the northeastern and northwestern parts of Alexandria. The flood related information obtained in this study will be useful to assist mitigating potential flood damages and future land use planning of both governorates of Egypt. Copyright © 2018 Elsevier B.V. All rights reserved.

Sorption, Leaching, and Surface Runoff of Beef Cattle Veterinary Pharmaceuticals under Simulated Irrigated Pasture Conditions

PubMed Central

Popova, Inna E.; Bair, Daniel A.; Tate, Kenneth W.; Parikh, Sanjai J.

2014-01-01

The use of veterinary pharmaceuticals in beef cattle has led to concerns associated with the development of antibiotic resistance in bacteria and endocrine disruption in aquatic organisms. Despite the potential negative consequences, data on the transport and mitigation of pharmaceuticals in grazed watersheds with irrigated pasture are scarce. The objective of this study was to assess the transport of common beef cattle pharmaceuticals (i.e., oxytetracycline, chlortetracycline, ivermectin) via surface runoff and leachate from manure amended to grass-vegetated soil boxes under irrigated pasture conditions. The transport of pharmaceuticals from animal manure in surface runoff and soil leachate was relatively low and appears to be limited by desorption and transport of pharmaceuticals entrained in the manure. In surface runoff, less than 4.2% of applied pharmaceuticals in manure (initial concentration: 0.2 mg kg−1 of manure) were detected after three weeks of irrigation. Concentrations of pharmaceuticals in surface runoff and leachate never exceeded 0.5 µg L−1. The major portion of pharmaceuticals (up to 99%) was retained in the manure or in the soil directly beneath the manure application site. Based on the minimal transport of oxytetracycline, chlortetracycline, and ivermectin, the risk of significant transport for these targeted beef cattle pharmaceuticals to surface water and groundwater from manure on irrigated pasture appears to be relatively low. PMID:24216368

The geomicrobiology of the Greenland Ice Sheet: impact on DOC export (Invited)

NASA Astrophysics Data System (ADS)

Wadham, J. L.; Stibal, M.; Lawson, E. C.; Barnett, M. J.; Hasan, F.; Telling, J.; Anesio, A.; Lis, G.; Cullen, D.; Butler, C.; Tranter, M.; Nienow, P. W.

2010-12-01

The Greenland Ice Sheet (GrIS) is the largest mass of ice in the northern hemisphere, and contributes ~370 km3 in runoff annually to the Arctic Ocean. While recent work has highlighted runoff increases of up to 100% from the GrIS over the next century, very little is known about the associated impacts upon rates of sediment-bound and dissolved organic carbon export from the ice sheet to the coastal ocean. This is relevant given recent work that has suggested that the high proportion of labile dissolved organic carbon (DOC) present in glacial runoff may be important in sustaining the productivity of ecosystems downstream. Here we report the phylogenetic and functional diversity of micro-organisms inhabiting the surface and basal regions of the Greenland Ice Sheet (at Leverett Glacier, SW Greenland), and whose activity influences the biogeochemical composition of runoff. Real time PCR data on runoff, together with 16S-rRNA bacterial clone libraries on sediments, demonstrate a subglacial microbial community that contrasts phylogenetically and functionally with the ice sheet surface ecosystem. We envisage that large sectors of the subglacial environment are microbially active, with overridden paleosols and in-washed surface organic matter providing a carbon substrate for a range of metabolic pathways. This includes methanogenesis which proceeds at rates similar to deep ocean sediments and via a CO2/H2 pathway. These subglacial microbial communities serve to chemically modify the DOC composition of meltwater inputs from the ice sheet surface and modulate the reactivity of bulk DOC exported in runoff. Evidence for subglacial microbial influences on DOC in runoff includes elevated concentrations of dissolved carbohydrates (e.g. glucose and fructose of up to 1 μmol/L), which are preferentially exported during subglacial outburst events. We examine the temporal changes in DOC export in runoff from the ice sheet over a full melt season, and consider how changes in total runoff over the coming century may perturb this contribution.

Water-quality characteristics of urban runoff and estimates of annual loads in the Tampa Bay area, Florida, 1975-80

USGS Publications Warehouse

Lopez, M.A.; Giovannelli, R.F.

1984-01-01

Rainfall, runoff, and water quality data were collected at nine urban watersheds in the Tampa Bay area from 1975 to 1980. Watershed drainage area ranged from 0.34 to 0.45 sq mi. Land use was mixed. Development ranged from a mostly residential watershed with a 19% impervious surface, to a commercial-residential watershed with a 61% impervious surface. Average biochemical oxygen demand concentrations of base flow at two sites and of stormwater runoff at five sites exceeded treated sewage effluent standards. Average coliform concentrations of stormwater runoff at all sites were several orders of magnitude greater than standards for Florida Class III receiving water (for recreation or propagation and management of fish and wildlife). Average concentrations of lead and zinc in stormwater runoff were consistently higher than Class III standards. Stormwater-runoff loads and base-flow concentrations of biochemical oxygen demand, chemical oxygen demand, total nitrogen, total organic nitrogen, total phosphorus, and lead were related to runoff volume, land use, urban development, and antecedent daily rainfall by multiple linear regression. Stormwater-runoff volume was related to pervious area, hydraulically connected impervious surfaces, storm rainfall, and soil-infiltration index. Base-flow daily discharge was related to drainage area and antecedent daily rainfall. The flow regression equations of this report were used to compute 1979 water-year loads of biochemical oxygen demand, chemical oxygen demand, total nitrogen, total organic nitrogen, total phosphorus , and total lead for the nine Tampa Bay area urban watersheds. (Lantz-PTT)

"Efficiency Space" - A Framework for Evaluating Joint Evaporation and Runoff Behavior

NASA Technical Reports Server (NTRS)

Koster, Randal

2014-01-01

At the land surface, higher soil moisture levels generally lead to both increased evaporation for a given amount of incoming radiation (increased evaporation efficiency) and increased runoff for a given amount of precipitation (increased runoff efficiency). Evaporation efficiency and runoff efficiency can thus be said to vary with each other, motivating the development of a unique hydroclimatic analysis framework. Using a simple water balance model fitted, in different experiments, with a wide variety of functional forms for evaporation and runoff efficiency, we transform net radiation and precipitation fields into fields of streamflow that can be directly evaluated against observations. The optimal combination of the functional forms the combination that produces the most skillful stream-flow simulations provides an indication for how evaporation and runoff efficiencies vary with each other in nature, a relationship that can be said to define the overall character of land surface hydrological processes, at least to first order. The inferred optimal relationship is represented herein as a curve in efficiency space and should be valuable for the evaluation and development of GCM-based land surface models, which by this measure are often found to be suboptimal.

Modelling surface runoff and water fluxes over contrasted soils in pastoral Sahel: evaluation of the ALMIP2 land surface models over the Gourma region in Mali

USDA-ARS?s Scientific Manuscript database

Land surface processes play an important role in West African monsoon variability and land –atmosphere coupling has been shown to be particularly important in the Sahel. In addition, the evolution of hydrological systems in this region, and particularly the increase of surface water and runoff coeff...

Pollution characteristics of surface runoff under different restoration types in manganese tailing wasteland.

PubMed

Wang, Jun; Cheng, Qingyu; Xue, Shengguo; Rajendran, Manikandan; Wu, Chuan; Liao, Jiaxin

2018-04-01

A great deal of manganese and associated heavy metals (such as Ni, Cu, Zn, Cd, Pb, etc.) was produced in manganese mining, smelting, and other processes and weathering and leaching of waste slag, which entered rainwater runoff by different means under the action of rainfall runoff. It caused heavy metal pollution in water environment to surrounding areas, and then environmental and human health risks were becoming increasingly serious. In the Xiangtan manganese mine, we studied the characteristics of nutritional pollutants and heavy metals by using the method of bounded runoff plots on the manganese tailing wasteland after carrying out some site treatments using three different approaches, such as (1) exposed tailings, the control treatment (ET), (2) external-soil amelioration and colonization of Cynodon dactylon (Linn.) Pers. turf (EC), and (3) external-soil amelioration and seedling seeding propagation of Cynodon dactylon (Linn.) Pers. (ES). The research showed that the maximum runoff occurred in 20,140,712 rainfall events, and the basic law of runoff was EC area > ET area > ES area in the same rainfall event. The concentration of total suspended solids (TSS) and chemical oxygen demand (COD) of three ecological restoration areas adopted the following rule: ET area > EC area > ES area. Nitrogen (N) existed mainly in the form of water soluble while phosphorus (P) was particulate. The highest concentrations of total nitrogen (TN) and total phosphorus (TP) were 11.57 ± 2.99 mg/L in the EC area and 1.42 ± 0.56 mg/L in the ET area, respectively. Cr, Ni, Pb, Zn, Mn, and Cu in surface runoff from three restoration types all exceeded the class V level of the environmental quality standard for surface water except Cu in EC and ES areas. Pollution levels of heavy metals in surface runoff from three restoration areas are shown as follows: ET area > EC area > ES area. There was a significant positive correlation between TSS and runoff, COD, and TP. And this correlation was significant between total dissolved nitrogen (TDN), TN, total dissolved phosphorus (TDP), and TP. The six heavy metals (Cu, Ni, Pb, Zn, Mn, and Cr) in surface runoff of different ecological restoration areas were strongly related to each other, and were significantly related to the TSS.

Nutrient Runoff Losses from Liquid Dairy Manure Applied with Low-Disturbance Methods.

PubMed

Jokela, William; Sherman, Jessica; Cavadini, Jason

2016-09-01

Manure applied to cropland is a source of phosphorus (P) and nitrogen (N) in surface runoff and can contribute to impairment of surface waters. Tillage immediately after application incorporates manure into the soil, which may reduce nutrient loss in runoff as well as N loss via NH volatilization. However, tillage also incorporates crop residue, which reduces surface cover and may increase erosion potential. We applied liquid dairy manure in a silage corn ( L.)-cereal rye ( L.) cover crop system in late October using methods designed to incorporate manure with minimal soil and residue disturbance. These include strip-till injection and tine aerator-band manure application, which were compared with standard broadcast application, either incorporated with a disk or left on the surface. Runoff was generated with a portable rainfall simulator (42 mm h for 30 min) three separate times: (i) 2 to 5 d after the October manure application, (ii) in early spring, and (iii) after tillage and planting. In the postmanure application runoff, the highest losses of total P and dissolved reactive P were from surface-applied manure. Dissolved P loss was reduced 98% by strip-till injection; this result was not statistically different from the no-manure control. Reductions from the aerator band method and disk incorporation were 53 and 80%, respectively. Total P losses followed a similar pattern, with 87% reduction from injected manure. Runoff losses of N had generally similar patterns to those of P. Losses of P and N were, in most cases, lower in the spring rain simulations with fewer significant treatment effects. Overall, results show that low-disturbance manure application methods can significantly reduce nutrient runoff losses compared with surface application while maintaining residue cover better than incorporation by tillage. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Phosphorus mitigation during springtime runoff by amendments applied to grassed soil.

PubMed

Uusi-Kämppä, J; Turtola, E; Närvänen, A; Jauhiainen, L; Uusitalo, R

2012-01-01

Permanent grass vegetation on sloping soils is an option to protect fields from erosion, but decaying grass may liberate considerable amounts of dissolved reactive P (DRP) in springtime runoff. We studied the effects of freezing and thawing of grassed soil on surface runoff P concentrations by indoor rainfall simulations and tested whether the peak P concentrations could be reduced by amending the soil with P-binding materials containing Ca or Fe. Forty grass-vegetated soil blocks (surface area 0.045 m, depth 0.07 m) were retrieved from two permanent buffer zones on a clay and loam soil in southwest Finland. Four replicates were amended with either: (i) gypsum from phosphoric acid processing (CaSO × 2HO, 6 t ha), (ii) chalk powder (CaCO, 3.3 t ha), (iii) Fe-gypsum (6 t ha) from TiO processing, or (iv) granulated ferric sulfate (Fe[SO], 0.7 t ha), with four replicates serving as untreated controls. Rainfall (3.3 h × 5 mm h) was applied on presaturated samples set at a slope of 5% and the surface runoff was analyzed for DRP, total dissolved P (TDP), total P (TP), and suspended solids. Rainfall simulation was repeated twice after the samples were frozen. Freezing and thawing of the samples increased the surface runoff DRP concentration of the control treatment from 0.19 to 0.46 mg L, up to 2.6-3.7 mg L, with DRP being the main P form in surface runoff. Compared with the controls, surface runoff from soils amended with Fe compounds had 57 to 80% and 47 to 72% lower concentrations of DRP and TP, respectively, but the gypsum and chalk powder did not affect the P concentrations. Thus, amendments containing Fe might be an option to improve DRP retention in, e.g., buffer zones. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Hydrological Response to Land Cover Changes and Human Activities in Arid Regions Using a Geographic Information System and Remote Sensing

PubMed Central

Mahmoud, Shereif H.; Alazba, A. A.

2015-01-01

The hydrological response to land cover changes induced by human activities in arid regions has attracted increased research interest in recent decades. The study reported herein assessed the spatial and quantitative changes in surface runoff resulting from land cover change in the Al-Baha region of Saudi Arabia between 1990 and 2000 using an ArcGIS-surface runoff model and predicted land cover and surface runoff depth in 2030 using Markov chain analysis. Land cover maps for 1990 and 2000 were derived from satellite images using ArcGIS 10.1. The findings reveal a 26% decrease in forest and shrubland area, 28% increase in irrigated cropland, 1.5% increase in sparsely vegetated land and 0.5% increase in bare soil between 1990 and 2000. Overall, land cover changes resulted in a significant decrease in runoff depth values in most of the region. The decrease in surface runoff depth ranged from 25-106 mm/year in a 7020-km2 area, whereas the increase in such depth reached only 10 mm/year in a 243-km2 area. A maximum increase of 73 mm/year was seen in a limited area. The surface runoff depth decreased to the greatest extent in the central region of the study area due to the huge transition in land cover classes associated with the construction of 25 rainwater harvesting dams. The land cover prediction revealed a greater than twofold increase in irrigated cropland during the 2000-2030 period, whereas forest and shrubland are anticipated to occupy just 225 km2 of land area by 2030, a significant decrease from the 747 km2 they occupied in 2000. Overall, changes in land cover are predicted to result in an annual increase in irrigated cropland and dramatic decline in forest area in the study area over the next few decades. The increase in surface runoff depth is likely to have significant implications for irrigation activities. PMID:25923712

SHEPHERD CREEK, CINCINNATI, OH: USING TRADABLE CREDITS TO CONTROL EXCESS STORMWATER RUNOFF

EPA Science Inventory

The problem of managing stormwater runoff grows apace with continued urbanization, yet the management tools for this growing non-point source problem have not fully kept up. The rapid growth of stormwater utilities around the nation is an important step toward providing an ef...

Groundwater flood of a river terrace in southwest Wisconsin, USA

NASA Astrophysics Data System (ADS)

Gotkowitz, Madeline B.; Attig, John W.; McDermott, Thomas

2014-09-01

Intense rainstorms in 2008 resulted in wide-spread flooding across the Midwestern United States. In Wisconsin, floodwater inundated a 17.7-km2 area on an outwash terrace, 7.5 m above the mapped floodplain of the Wisconsin River. Surface-water runoff initiated the flooding, but results of field investigation and modeling indicate that rapid water-table rise and groundwater inundation caused the long-lasting flood far from the riparian floodplain. Local geologic and geomorphic features of the landscape lead to spatial variability in runoff and recharge to the unconfined sand and gravel aquifer, and regional hydrogeologic conditions increased groundwater discharge from the deep bedrock aquifer to the river valley. Although reports of extreme cases of groundwater flooding are uncommon, this occurrence had significant economic and social costs. Local, state and federal officials required hydrologic analysis to support emergency management and long-term flood mitigation strategies. Rapid, sustained water-table rise and the resultant flooding of this high-permeability aquifer illustrate a significant aspect of groundwater system response to an extreme precipitation event. Comprehensive land-use planning should encompass the potential for water-table rise and groundwater flooding in a variety of hydrogeologic settings, as future changes in climate may impact recharge and the water-table elevation.

Hydrologic conditions controlling runoff generation immediately after wildfire

USGS Publications Warehouse

Ebel, Brian A.; Moody, John A.; Martin, Deborah A.

2012-01-01

We investigated the control of postwildfire runoff by physical and hydraulic properties of soil, hydrologic states, and an ash layer immediately following wildfire. The field site is within the area burned by the 2010 Fourmile Canyon Fire in Colorado, USA. Physical and hydraulic property characterization included ash thickness, particle size distribution, hydraulic conductivity, and soil water retention curves. Soil water content and matric potential were measured indirectly at several depths below the soil surface to document hydrologic states underneath the ash layer in the unsaturated zone, whereas precipitation and surface runoff were measured directly. Measurements of soil water content showed that almost no water infiltrated below the ash layer into the near-surface soil in the burned site at the storm time scale (i.e., minutes to hours). Runoff generation processes were controlled by and highly sensitive to ash thickness and ash hydraulic properties. The ash layer stored from 97% to 99% of rainfall, which was critical for reducing runoff amounts. The hydrologic response to two rain storms with different rainfall amounts, rainfall intensity, and durations, only ten days apart, indicated that runoff generation was predominantly by the saturation-excess mechanism perched at the ash-soil interface during the first storm and predominantly by the infiltration-excess mechanism at the ash surface during the second storm. Contributing area was not static for the two storms and was 4% (saturation excess) to 68% (infiltration excess) of the catchment area. Our results showed the importance of including hydrologic conditions and hydraulic properties of the ash layer in postwildfire runoff generation models.

A three-component hydrograph separation based on geochemical tracers in a tropical mountainous headwater catchment in northern Thailand

NASA Astrophysics Data System (ADS)

Hugenschmidt, C.; Ingwersen, J.; Sangchan, W.; Sukvanachaikul, Y.; Duffner, A.; Uhlenbrook, S.; Streck, T.

2014-02-01

Land-use change in the mountainous parts of northern Thailand is reflected by an increased application of agrochemicals, which may be lost to surface and groundwater. The close relation between flow paths and contaminant transport within hydrological systems requires recognizing and understanding the dominant hydrological processes. To date, the vast majority of studies on runoff generation have been conducted in temperate regions. Tropical regions suffer from a general lack of data, and little is known about runoff generation processes. To fill this knowledge gap, a three-component hydrograph separation based on geochemical tracers was carried out in a steep, remote and monsoon-dominated study site (7 km2) in northern Thailand. Silica and electrical conductivity (EC) were identified as useful tracers and were applied to calculate the fractions of groundwater (similar to pre-event water), shallow subsurface flow and surface runoff on stormflow. K+ was a useful indicator for surface runoff dynamics, and Ca2+ provided insights into groundwater behaviour. Nevertheless, neither measure was applicable for the quantification of runoff components. Cl- and further parameters (e.g. Na+, K+, and Mg2+) were also not helpful for flow path identification, nor were their concentrations distinguishable among the components. Groundwater contributed the largest fractions to stormflow (62-80%) throughout all events, followed by shallow subsurface flow (17-36%) and surface runoff (2-13%). Our results provide important insights into the dynamics of the runoff processes in the study area and may be used to assess the transport pattern of contaminants (i.e. agrochemicals) here.

Nutrients and sediment in frozen-ground runoff from no-till fields receiving liquid-dairy and solid-beef manures

USGS Publications Warehouse

Komiskey, Matthew J.; Stuntebeck, Todd D.; Frame, Dennis R.; Madison, Fred W.

2011-01-01

Nutrients and sediment in surface runoff from frozen agricultural fields were monitored within three small (16.0 ha [39.5 ac] or less), adjacent basins at a no-till farm in southwest Wisconsin during four winters from 2003 to 2004 through 2006 to 2007. Runoff depths and flow-weighted constituent concentrations were compared to determine the impacts of surface-applied liquid-dairy or solid-beef manure to frozen and/or snow-covered ground. Despite varying the manure type and the rate and timing of applications, runoff depths were not significantly different among basins within each winter period. Sediment losses were low (generally less than 22 kg ha−1 [20 lb ac−1] in any year) and any statistical differences in sediment concentrations among basins were not related to the presence or absence of manure or the amount of runoff. Concentrations and losses of total nitrogen and total phosphorus were significantly increased in basins that had either manure type applied less than one week preceding runoff. These increases occurred despite relatively low application rates. Lower concentrations and losses were measured in basins that had manure applied in fall and early winter and an extended period of time (months) had elapsed before the first runoff event. The highest mean, flow-weighted concentrations of total nitrogen (31.8 mg L−1) and total phosphorus (10.9 mg L−1) occurred in winter 2003 to 2004, when liquid-dairy manure was applied less than one week before runoff. On average, dissolved phosphorus accounted for over 80% of all phosphorus measured in runoff during frozen-ground periods. The data collected as part of this study add to the limited information on the quantity and quality of frozen-ground runoff at field edges, and the results highlight the importance of manure management decisions during frozen-ground periods to minimize nutrients lost in surface runoff.

HYSEP: A Computer Program for Streamflow Hydrograph Separation and Analysis

USGS Publications Warehouse

Sloto, Ronald A.; Crouse, Michele Y.

1996-01-01

HYSEP is a computer program that can be used to separate a streamflow hydrograph into base-flow and surface-runoff components. The base-flow component has traditionally been associated with ground-water discharge and the surface-runoff component with precipitation that enters the stream as overland runoff. HYSEP includes three methods of hydrograph separation that are referred to in the literature as the fixed interval, sliding-interval, and local-minimum methods. The program also describes the frequency and duration of measured streamflow and computed base flow and surface runoff. Daily mean stream discharge is used as input to the program in either an American Standard Code for Information Interchange (ASCII) or binary format. Output from the program includes table,s graphs, and data files. Graphical output may be plotted on the computer screen or output to a printer, plotter, or metafile.

Assessing the long-term effects of land use changes on runoff patterns and food production in a large lake watershed with policy implications.

PubMed

Sun, Zhandong; Lotz, Tom; Chang, Ni-Bin

2017-12-15

Effects of land use development on runoff patterns are salient at a hydrological response unit scale. However, quantitative analysis at the watershed scale is still a challenge due to the complex spatial heterogeneity of the upstream and downstream hydrological relationships and the inherent structure of drainage systems. This study aims to use the well-calibrated Soil and Water Assessment Tool (SWAT) to assess the response of hydrological processes under different land use scenarios in a large lake watershed (Lake Dongting) in the middle Yangtze River basin in China. Based on possible land use changes, scale-dependent land use scenarios were developed and parameters embedded in SWAT were calibrated and validated for hydrological systems analysis. This approach leads to the simulation of the land use change impacts on the hydrological cycle. Results indicated that evapotranspiration, surface runoff, groundwater flow, and water yield were affected by the land use change scenarios in different magnitudes. Overall, changes of land use and land cover have significant impacts on runoff patterns at the watershed scale in terms of both the total water yield (i.e., groundwater flow, surface runoff, and interflow, minus transmission losses) and the spatial distribution of runoff. The changes in runoff distribution were resulted in opposite impacts within the two land use scenarios including forest and agriculture. Water yield has a decrease of 1.8 percent in the forest-prone landscape scenario and an increase of 4.2 percent in the agriculture-rich scenario during the simulated period. Surface runoff was the most affected component in the hydrological cycle. Whereas surface runoff as part of water yield has a decrease of 8.2 percent in the forest- prone landscape scenario, there is an increase of 8.6 percent in the agriculture-rich landscape scenario. Different runoff patterns associated with each land use scenario imply the potential effect on flood or drought mitigation policy. Based on the results, key areas were identified to show that hydrological extreme mitigation and flood control can be coordinated by some land use regulations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Identification of soil P fractions that are associated with P loss from surface runoff under various cropping systems and fertilizer rates on sloped farmland

PubMed Central

Li, Xinghua; Wang, Baona; Yang, Tewu; Zhu, Duanwei; Nie, Zhongnan; Xu, Junchi

2017-01-01

Soil phosphorus (P) fractions and runoff P concentration were measured to understand the fate of soil P entering surface runoff water during summer cropping season of different double cropping systems under two fertilizer regimes. The dominant form of runoff P was particulate P (PP). Runoff total P (TP) was higher at the vegetative growth stage and lower at the crop reproductive stage. TP and PP were derived mainly from soil Olsen-P, Al-P and Fe-P and amounts increased with sediment content in runoff water. Runoff P discharge was closely related to the changes in soil P forms. Soil Olsen-P, mainly consisting of some Ca2-P and Al-P, was increased by elevating fertilizer rate. Along with crop growth, there were active interconversions among Olsen-P, Org-P, Fe-P and O-Al-P in the soil, and some available P converted into Ca10-P, with O-Fe-P possibly being a transitional form for this conversion. The oilseed rape/corn system had less runoff TP at the early stage, and wheat/sweet potato system had a lower runoff P at the late stage. Intercropping corn with sweet potato in the field with oilseed rape as a previous crop may be helpful for alleviating runoff P load during the summer in this region. PMID:28650990

Identification of soil P fractions that are associated with P loss from surface runoff under various cropping systems and fertilizer rates on sloped farmland.

PubMed

Li, Xinghua; Wang, Baona; Yang, Tewu; Zhu, Duanwei; Nie, Zhongnan; Xu, Junchi

2017-01-01

Soil phosphorus (P) fractions and runoff P concentration were measured to understand the fate of soil P entering surface runoff water during summer cropping season of different double cropping systems under two fertilizer regimes. The dominant form of runoff P was particulate P (PP). Runoff total P (TP) was higher at the vegetative growth stage and lower at the crop reproductive stage. TP and PP were derived mainly from soil Olsen-P, Al-P and Fe-P and amounts increased with sediment content in runoff water. Runoff P discharge was closely related to the changes in soil P forms. Soil Olsen-P, mainly consisting of some Ca2-P and Al-P, was increased by elevating fertilizer rate. Along with crop growth, there were active interconversions among Olsen-P, Org-P, Fe-P and O-Al-P in the soil, and some available P converted into Ca10-P, with O-Fe-P possibly being a transitional form for this conversion. The oilseed rape/corn system had less runoff TP at the early stage, and wheat/sweet potato system had a lower runoff P at the late stage. Intercropping corn with sweet potato in the field with oilseed rape as a previous crop may be helpful for alleviating runoff P load during the summer in this region.

Modeling the Impact of Soil and Water Conservation on Surface and Ground Water Based on the SCS and Visual Modflow

PubMed Central

Wang, Hong; Gao, Jian-en; Zhang, Shao-long; Zhang, Meng-jie; Li, Xing-hua

2013-01-01

Soil and water conservation measures can impact hydrological cycle, but quantitative analysis of this impact is still difficult in a watershed scale. To assess the effect quantitatively, a three-dimensional finite-difference groundwater flow model (MODFLOW) with a surface runoff model–the Soil Conservation Service (SCS) were calibrated and applied based on the artificial rainfall experiments. Then, three soil and water conservation scenarios were simulated on the sand-box model to assess the effect of bare slope changing to grass land and straw mulching on water volume, hydraulic head, runoff process of groundwater and surface water. Under the 120 mm rainfall, 60 mm/h rainfall intensity, 5 m2 area, 3° slope conditions, the comparative results indicated that the trend was decrease in surface runoff and increase in subsurface runoff coincided with the land-use converted from bare slope to grass land and straw mulching. The simulated mean surface runoff modulus was 3.64×10−2 m3/m2/h in the bare slope scenario, while the observed values were 1.54×10−2 m3/m2/h and 0.12×10−2 m3/m2/h in the lawn and straw mulching scenarios respectively. Compared to the bare slope, the benefits of surface water reduction were 57.8% and 92.4% correspondingly. At the end of simulation period (T = 396 min), the simulated mean groundwater runoff modulus was 2.82×10−2 m3/m2/h in the bare slope scenario, while the observed volumes were 3.46×10−2 m3/m2/h and 4.91×10−2 m3/m2/h in the lawn and straw mulching scenarios respectively. So the benefits of groundwater increase were 22.7% and 60.4% correspondingly. It was concluded that the soil and water conservation played an important role in weakening the surface runoff and strengthening the underground runoff. Meanwhile the quantitative analysis using a modeling approach could provide a thought for the study in a watershed scale to help decision-makers manage water resources. PMID:24244427

Evaluation of an Infiltration Model with Microchannels

NASA Astrophysics Data System (ADS)

Garcia-Serrana, M.; Gulliver, J. S.; Nieber, J. L.

2015-12-01

This research goal is to develop and demonstrate the means by which roadside drainage ditches and filter strips can be assigned the appropriate volume reduction credits by infiltration. These vegetated surfaces convey stormwater, infiltrate runoff, and filter and/or settle solids, and are often placed along roads and other impermeable surfaces. Infiltration rates are typically calculated by assuming that water flows as sheet flow over the slope. However, for most intensities water flow occurs in narrow and shallow micro-channels and concentrates in depressions. This channelization reduces the fraction of the soil surface covered with the water coming from the road. The non-uniform distribution of water along a hillslope directly affects infiltration. First, laboratory and field experiments have been conducted to characterize the spatial pattern of flow for stormwater runoff entering onto the surface of a sloped surface in a drainage ditch. In the laboratory experiments different micro-topographies were tested over bare sandy loam soil: a smooth surface, and three and five parallel rills. All the surfaces experienced erosion; the initially smooth surface developed a system of channels over time that increased runoff generation. On average, the initially smooth surfaces infiltrated 10% more volume than the initially rilled surfaces. The field experiments were performed in the side slope of established roadside drainage ditches. Three rates of runoff from a road surface into the swale slope were tested, representing runoff from 1, 2, and 10-year storm events. The average percentage of input runoff water infiltrated in the 32 experiments was 67%, with a 21% standard deviation. Multiple measurements of saturated hydraulic conductivity were conducted to account for its spatial variability. Second, a rate-based coupled infiltration and overland model has been designed that calculates stormwater infiltration efficiency of swales. The Green-Ampt-Mein-Larson assumptions were implemented to calculate infiltration along with a kinematic wave model for overland flow that accounts for short-circuiting of flow. Additionally, a sensitivity analysis on the parameters implemented in the model has been performed. Finally, the field experiments results have been used to quantify the validity of the coupled model.

Distribution of pesticides in dust particles in urban environments.

PubMed

Richards, Jaben; Reif, Ruben; Luo, Yuzhuo; Gan, Jay

2016-07-01

In regions with a mild climate, pesticides are often used around homes for pest control. Recent monitoring studies have linked pesticide use in residential areas to aquatic toxicity in urban surface water ecosystems, and suggested dust particles on paved surfaces as an important source of pesticides. To test the hypothesis that dust on hard surfaces is a significant source of pesticides, we evaluated spatial and temporal patterns of current-use insecticides in Southern California, and further explored their distribution as a function of particle sizes. Pyrethroid insecticides were detected in dust from the driveway, curb gutter and street at 53.5-94.8%, with median concentrations of 1-46 ng g(-1). Pyrethroid residues were uniformly distributed in areas adjacent to a house, suggesting significant redistribution. The total levels of pyrethroids in dust significantly (p < 0.01) decreased from October to February, suggesting rainfalls as a major mechanism to move pesticide residues offsite. Fipronil as well as its degradation products, were detected at 50.6-75.5%, and spatial and temporal patterns of fipronil residues suggested rapid transformations of fipronil to its biologically active intermediates. Moreover, pyrethroids were found to be enriched in fine particles that have a higher mobility in runoff than coarse particles. Results from this study highlight the widespread occurrence of pesticides in outdoor dust around homes and the potential contribution to downstream surface water contamination via rain-induced runoff. Copyright © 2016 Elsevier Ltd. All rights reserved.

CONTROLLING EXCESS STORM WATER RUNOFF WITH TRADABLE CREDITS

EPA Science Inventory

Development that increases the impervious surface in a watershed causes excess storm water runoff (SWR) that has been identified as a major contributor to stream and riparian habitat degradation. Reduction of storm water runoff can be achieved through establishment of a number of...

Herbicide volatilization trumps runoff losses, a multi-year investigation

USDA-ARS?s Scientific Manuscript database

Surface runoff and volatilization are two processes critical to herbicide off-site transport. To determine the relevance of these off-site transport mechanisms, runoff and turbulent vapor fluxes were simultaneously monitored on the same site for eight years. Site location, herbicide formulations, ...

A MULTIDISCIPLINARY APPROACH TO MANAGING STORMWATER RUNOFF IN AN URBAN WATERSHED

EPA Science Inventory

Increased impervious surface (e.g., roofs, pavement) due to urbanization can lead to excess runoff throughout a watershed, overwhelming the existing stormwater infrastructure. High volumes of runoff, delivered to receiving streams over short durations at high flow rates, negative...

Assessing the Impact of Urbanization on Direct Runoff Using Improved Composite CN Method in a Large Urban Area.

PubMed

Li, Chunlin; Liu, Miao; Hu, Yuanman; Shi, Tuo; Zong, Min; Walter, M Todd

2018-04-17

Urbanization is one of the most widespread anthropogenic activities, which brings a range of physical and biochemical changes to hydrological system and processes. Increasing direct runoff caused by land use change has become a major challenge for urban ecological security. Reliable prediction of the quantity and rate of surface runoff is an inherently difficult and time-consuming task for large ungauged urban areas. In this study, we combined Geographic Information System and remote sensing technology with an improved Soil Conservation Service curve number model to evaluate the effects of land use change on direct runoff volume of the four-ring area in Shenyang, China, and analyzed trends of direct runoff at different scales. Through analyzing trends of direct runoff from 1984 to 2015 at different scales, we explored how urbanization and other potential factors affect direct runoff changes. Total direct runoff volume increased over time, and trends varied from the inner urban area to suburban area. Zones 1 and 2 had a tendency toward decreasing direct runoff volume and risks, while Zones 3 and 4 showed gradual increases at both regional and pixel scales. The most important influence on direct runoff change was urban surface change caused by urbanization. This study presents a framework for identifying hotspots of runoff increase, which can provide important guidance to urban managers in future green infrastructure planning, in the hopes of improving the security of urban water ecological patterns.

Rainfall-induced runoff from exposed streambed sediments: an important source of water pollution.

PubMed

Frey, S K; Gottschall, N; Wilkes, G; Grégoire, D S; Topp, E; Pintar, K D M; Sunohara, M; Marti, R; Lapen, D R

2015-01-01

When surface water levels decline, exposed streambed sediments can be mobilized and washed into the water course when subjected to erosive rainfall. In this study, rainfall simulations were conducted over exposed sediments along stream banks at four distinct locations in an agriculturally dominated river basin with the objective of quantifying the potential for contaminant loading from these often overlooked runoff source areas. At each location, simulations were performed at three different sites. Nitrogen, phosphorus, sediment, fecal indicator bacteria, pathogenic bacteria, and microbial source tracking (MST) markers were examined in both prerainfall sediments and rainfall-induced runoff water. Runoff generation and sediment mobilization occurred quickly (10-150 s) after rainfall initiation. Temporal trends in runoff concentrations were highly variable within and between locations. Total runoff event loads were considered large for many pollutants considered. For instance, the maximum observed total phosphorus runoff load was on the order of 1.5 kg ha. Results also demonstrate that runoff from exposed sediments can be a source of pathogenic bacteria. spp. and spp. were present in runoff from one and three locations, respectively. Ruminant MST markers were also present in runoff from two locations, one of which hosted pasturing cattle with stream access. Overall, this study demonstrated that rainfall-induced runoff from exposed streambed sediments can be an important source of surface water pollution. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Assessing the Impact of Urbanization on Direct Runoff Using Improved Composite CN Method in a Large Urban Area

PubMed Central

Li, Chunlin; Liu, Miao; Hu, Yuanman; Shi, Tuo; Zong, Min; Walter, M. Todd

2018-01-01

Urbanization is one of the most widespread anthropogenic activities, which brings a range of physical and biochemical changes to hydrological system and processes. Increasing direct runoff caused by land use change has become a major challenge for urban ecological security. Reliable prediction of the quantity and rate of surface runoff is an inherently difficult and time-consuming task for large ungauged urban areas. In this study, we combined Geographic Information System and remote sensing technology with an improved Soil Conservation Service curve number model to evaluate the effects of land use change on direct runoff volume of the four-ring area in Shenyang, China, and analyzed trends of direct runoff at different scales. Through analyzing trends of direct runoff from 1984 to 2015 at different scales, we explored how urbanization and other potential factors affect direct runoff changes. Total direct runoff volume increased over time, and trends varied from the inner urban area to suburban area. Zones 1 and 2 had a tendency toward decreasing direct runoff volume and risks, while Zones 3 and 4 showed gradual increases at both regional and pixel scales. The most important influence on direct runoff change was urban surface change caused by urbanization. This study presents a framework for identifying hotspots of runoff increase, which can provide important guidance to urban managers in future green infrastructure planning, in the hopes of improving the security of urban water ecological patterns. PMID:29673182

Measurement of surface water runoff from plots of two different sizes

NASA Astrophysics Data System (ADS)

Joel, Abraham; Messing, Ingmar; Seguel, Oscar; Casanova, Manuel

2002-05-01

Intensities and amounts of water infiltration and runoff on sloping land are governed by the rainfall pattern and soil hydraulic conductivity, as well as by the microtopography and soil surface conditions. These components are closely interrelated and occur simultaneously, and their particular contribution may change during a rainfall event, or their effects may vary at different field scales. The scale effect on the process of infiltration/runoff was studied under natural field and rainfall conditions for two plot sizes: small plots of 0·25 m2 and large plots of 50 m2. The measurements were carried out in the central region of Chile in a piedmont most recently used as natural pastureland. Three blocks, each having one large plot and five small plots, were established. Cumulative rainfall and runoff quantities were sampled every 5 min. Significant variations in runoff responses to rainfall rates were found for the two plot sizes. On average, large plots yielded only 40% of runoff quantities produced on small plots per unit area. This difference between plot sizes was observed even during periods of continuous runoff.

Variability common to global sea surface temperatures and runoff in the conterminous United States

USGS Publications Warehouse

McCabe, Gregory J.; Wolock, David M.

2014-01-01

Singular value decomposition (SVD) is used to identify the variability common to global sea surface temperatures (SSTs) and water-balance-modeled water-year (WY) runoff in the conterminous United States (CONUS) for the 1900–2012 period. Two modes were identified from the SVD analysis; the two modes explain 25% of the variability in WY runoff and 33% of the variability in WY SSTs. The first SVD mode reflects the variability of the El Niño–Southern Oscillation (ENSO) in the SST data and the hydroclimatic effects of ENSO on WY runoff in the CONUS. The second SVD mode is related to variability of the Atlantic multidecadal oscillation (AMO). An interesting aspect of these results is that both ENSO and AMO appear to have nearly equivalent effects on runoff variability in the CONUS. However, the relatively small amount of variance explained by the SVD analysis indicates that there is little covariation between runoff and SSTs, suggesting that SSTs may not be a viable predictor of runoff variability for most of the conterminous United States.

Tillage impact on herbicide loss by surface runoff and lateral subsurface flow

USDA-ARS?s Scientific Manuscript database

There is worldwide interest in conservation tillage practices because they can reduce surface runoff, agrichemical, and sediment loss from farm fields. Since these practices typically increase infiltration, their use may increase subsurface transport of water-soluble contaminants. Thus, to assess lo...

CONTROLLING STORM WATER RUNOFF WITH TRADABLE CREDITS FOR IMPERVIOUS SURFACES

EPA Science Inventory

Storm water flow off impervious surface in a watershed can lead to stream degradation, habitat alteration, low base flows and toxic leading. We show that a properly designed tradable runoff credit (TRC) system creates economic incentives for landowners to employ best management p...

Managing urban runoff in residential neighborhoods: Nitrogen and phosphorus in lawn irrigation driven runoff.

PubMed

Toor, Gurpal S; Occhipinti, Marti L; Yang, Yun-Ya; Majcherek, Tammy; Haver, Darren; Oki, Lorence

2017-01-01

Sources and mechanisms of nutrient transport in lawn irrigation driven surface runoff are largely unknown. We investigated the transport of nitrogen (N) and phosphorus (P) in lawn irrigation driven surface runoff from a residential neighborhood (28 ha) of 56% impervious and 44% pervious areas. Pervious areas encompassing turfgrass (lawns) in the neighborhood were irrigated with the reclaimed water in common areas during the evening to late night and with the municipal water in homeowner's lawns during the morning. The stormwater outlet pipe draining the residential neighborhood was instrumented with a flow meter and Hach autosampler. Water samples were collected every 1-h and triple composite samples were obtained at 3-h intervals during an intensive sampling period of 1-week. Mean concentrations, over 56 sampling events, of total N (TN) and total P (TP) in surface runoff at the outlet pipe were 10.9±6.34 and 1.3±1.03 mg L-1, respectively. Of TN, the proportion of nitrate-N was 58% and other-N was 42%, whereas of TP, orthophosphate-P was 75% and other-P was 25%. Flow and nutrient (N and P) concentrations were lowest from 6:00 a.m. to noon, which corresponded with the use of municipal water and highest from 6:00 p.m. to midnight, which corresponded with the use of reclaimed water. This data suggests that N and P originating in lawn irrigation driven surface runoff from residential catchments is an important contributor of nutrients in surface waters.

Managing urban runoff in residential neighborhoods: Nitrogen and phosphorus in lawn irrigation driven runoff

PubMed Central

Occhipinti, Marti L.; Yang, Yun-Ya; Majcherek, Tammy; Haver, Darren; Oki, Lorence

2017-01-01

Sources and mechanisms of nutrient transport in lawn irrigation driven surface runoff are largely unknown. We investigated the transport of nitrogen (N) and phosphorus (P) in lawn irrigation driven surface runoff from a residential neighborhood (28 ha) of 56% impervious and 44% pervious areas. Pervious areas encompassing turfgrass (lawns) in the neighborhood were irrigated with the reclaimed water in common areas during the evening to late night and with the municipal water in homeowner’s lawns during the morning. The stormwater outlet pipe draining the residential neighborhood was instrumented with a flow meter and Hach autosampler. Water samples were collected every 1-h and triple composite samples were obtained at 3-h intervals during an intensive sampling period of 1-week. Mean concentrations, over 56 sampling events, of total N (TN) and total P (TP) in surface runoff at the outlet pipe were 10.9±6.34 and 1.3±1.03 mg L–1, respectively. Of TN, the proportion of nitrate–N was 58% and other–N was 42%, whereas of TP, orthophosphate–P was 75% and other–P was 25%. Flow and nutrient (N and P) concentrations were lowest from 6:00 a.m. to noon, which corresponded with the use of municipal water and highest from 6:00 p.m. to midnight, which corresponded with the use of reclaimed water. This data suggests that N and P originating in lawn irrigation driven surface runoff from residential catchments is an important contributor of nutrients in surface waters. PMID:28604811

Phosphorus runoff losses from subsurface-applied poultry litter on coastal plain soils.

PubMed

Kibet, Leonard C; Allen, Arthur L; Kleinman, Peter J A; Feyereisen, Gary W; Church, Clinton; Saporito, Lou S; Way, Thomas R

2011-01-01

The application of poultry litter to soils is a water quality concern on the Delmarva Peninsula, as runoff contributes P to the eutrophic Chesapeake Bay. This study compared a new subsurface applicator for poultry litter with conventional surface application and tillage incorporation of litter on a Coastal Plain soil under no-till management. Monolith lysimeters (61 cm by 61 cm by 61 cm) were collected immediately after litter application and subjected to rainfall simulation (61 mm h(-1) 1 h) 15 and 42 d later. In the first rainfall event, subsurface application of litter significantly lowered total P losses in runoff (1.90 kg ha(-1)) compared with surface application (4.78 kg ha(-1)). Losses of P with subsurface application were not significantly different from disked litter or an unamended control. By the second event, total P losses did not differ significantly between surface and subsurface litter treatments but were at least twofold greater than losses from the disked and control treatments. A rising water table in the second event likely mobilized dissolved forms of P in subsurface-applied litter to the soil surface, enriching runoff water with P. Across both events, subsurface application of litter did not significantly decrease cumulative losses of P relative to surface-applied litter, whereas disking the litter into the soil did. Results confirm the short-term reduction of runoff P losses with subsurface litter application observed elsewhere but highlight the modifying effect of soil hydrology on this technology's ability to minimize P loss in runoff.

The Effects Of Urban Landscape Patterns On Rainfall-Runoff Processes At Small Scale

NASA Astrophysics Data System (ADS)

Chen, L.

2016-12-01

Many studies have indicated that urban landscape change may alter rainfall-runoff processes. However, how urban landscape pattern affect this process is little addressed. In this study, the hydrological effects of landscape pattern on rainfall-runoff processes at small-scale was explored. Twelve residential blocks with independent drainage systems in Beijing were selected as case study areas. Impervious metrics of these blocks, i.e., total impervious area (TIA) and directly connected impervious area (DCIA), were identified. A drainage index describing catchment general drainage load and the overland flow distance, Ad, was estimated and used as one of the landscape spatial metrics. Three scenarios were designed to test the potential influence of impervious surface pattern on runoff processes. Runoff variables including total and peak runoff depth (Qt and Qp) were simulated under different rainfall conditions by Storm Water Management Model (SWMM). The relationship between landscape patterns and runoff variables were analyzed, and further among the three scenarios. The results demonstrated that, in small urban blocks, spatial patterns have inherent influences on rainfall-runoff processes. Specifically, (1) Imperviousness acts as effective indicators in predicting both Qt and Qp. As rainfall intensity increases, the major affecting factor changes from DCIA to TIA for both Qt and Qp; (2) Increasing the size of drainage area dominated by each drainage inlet will benefit the block peak flow mitigation; (3) Different spatial concentrations of impervious surfaces have inherent influences on Qp, when impervious surfaces located away from the outlet can reduce the peak flow discharge. These findings may provide insights into the role of urban landscape patterns in driving rainfall-runoff responses in urbanization, which is essential for urban planning and stormwater management.

Environmental and Cultural Impact Proposed Tennessee Colony Reservoir, Trinity River, Texas. Volume V. Appendix G.

DTIC Science & Technology

1972-01-01

allocation. Pri- marily it is concerned with any land use that increases surface water runoff and soil compaction, two phenomena that decrease recharge... runoff . Forested filter strips between range and reser- voir boundary should be developed as a land use for water quality control and quail habitat. High...shown on Plates G-10 and G-11) some measures will also be necessary to prevent fertilizer pollution of the reservoir from excessive surface runoff . G

Occurrence of alachlor and its sulfonated metabolite in rivers and reservoirs of the midwestern United States: The importance of sulfonation in the transport of chloroacetanilide herbicides

USGS Publications Warehouse

Thurman, E.M.; Goolsby, D.A.; Aga, D.S.; Pomes, M.L.; Meyer, M.T.

1996-01-01

Alachlor and its metabolite, 2-[(2',6'-diethylphenyl)- (methoxymethyl)amino]-2-oxoethanesulfonate (ESA), were identified in 76 reservoirs in the midwestern United States using immunoassay, liquid chromatography, and gas chromatography/mass spectrometry. The median concentration of ESA (0.48 ??g/L) exceeded the median concentration of alachlor (<0.05 ??g/L), with highest values in the upper Midwest. ESA also was detected in the Mississippi River from the mouth to the headwaters at concentrations of 0.2-1.5 ??g/L, exceeding the concentration of alachlor. In a field runoff study, alachlor rapidly formed ESA. It is hypothesized that a glutathione conjugate forms, which later oxidizes in soil to ESA. The removal of the chlorine atom lessens the toxicity of the parent compound and increases runoff potential. It is hypothesized further that sulfonic acid metabolites of other chloroacetanilides, including acetochlor, butachlor, metolachlor, and propachlor, also occur in surface water.

Effects of Changing Climate During the Snow Ablation Season on Seasonal Streamflow Forecasts

NASA Astrophysics Data System (ADS)

Gutzler, D. S.; Chavarria, S. B.

2017-12-01

Seasonal forecasts of total surface runoff (Q) in snowmelt-dominated watersheds derive most of their prediction skill from the historical relationship between late winter snowpack (SWE) and subsequent snowmelt runoff. Across the western US, however, the relationship between SWE and Q is weakening as temperatures rise. We describe the effects of climate variability and change during the springtime snow ablation season on water supply outlooks (forecasts of Q) for southwestern rivers. As snow melts earlier, the importance of post-snow rainfall increases: interannual variability of spring season precipitation accounts for an increasing fraction of the variability of Q in recent decades. The results indicate that improvements to the skill of S2S forecasts of spring season temperature and precipitation would contribute very significantly to water supply outlooks that are now based largely on observed SWE. We assess this hypothesis using historical data from several snowpack-dominated basins in the American Southwest (Rio Grande, Pecos, and Gila Rivers) which are undergoing rapid climate change.

Effect of surface incorporation of broiler litter applied to no-till cotton on runoff quality.

PubMed

Adeli, A; Shankle, M W; Tewolde, H; Brooks, J P; Sistani, K R; McLaughlin, M R; Rowe, D E

2011-01-01

Surface application of broiler litter to no-till cotton could lead to degradation of water quality. Incorporation of broiler litter into the top surface soil (0.05 m) could alleviate this risk. A 2-yr field study was conducted on a silt loam upland soil to determine the effect of incorporation of broiler litter into the soil surface on nutrient and bacterial transport in runoff. The experimental design was a randomized complete block with four treatments and three replications. Treatments were (i) unfertilized control; (ii) surface-appliedbroiler litter at 7.8 Mg ha(-1) without incorporation; (iii) surface-applied broiler litter at 7.8 Mg ha(-1) with immediate incorporation; and (iv) inorganic fertilizer N (urea ammonium nitrate, 32% N) and inorganic fertilizer P (triple superphosphate) at the recommended rate. Phosphorus was surface appliedat 25 kg ha(-1) and N was injected at 101 kg ha(-1) into the soil using a commercial liquid fertilizer applicator. Runoff was collected from small runoff plots (2.4 m by 1.6 m) established at the bottom side of main plots (13.7 m by 6.0 m). Incorporation of broiler litter reduced total N (TN), NO3-N, water soluble P (WSP), and total P (TP) concentrations in runoffby 35, 25, 61, and 64%, respectively, and litter-associated bacteria by two to three orders of magnitude compared with unincorporated treatment. No significant difference in total suspended solids (TSS) in runoffwas obtained between incorporated and unincorporated treatments. Incorporation of broiler litter into the surface soil in the no-till system immediately after application minimized the potential risk for surface nutrient losses and bacteria transport in runoff.

Concentrations of polycyclic aromatic hydrocarbons (PAHs) and azaarenes in runoff from coal-tar- and asphalt-sealcoated pavement

USGS Publications Warehouse

Mahler, Barbara J.; Van Metre, Peter C.; Foreman, William T.

2014-01-01

Coal-tar-based sealcoat, used extensively on parking lots and driveways in North America, is a potent source of PAHs. We investigated how concentrations and assemblages of PAHs and azaarenes in runoff from pavement newly sealed with coal-tar-based (CT) or asphalt-based (AS) sealcoat changed over time. Samples of simulated runoff were collected from pavement 5 h to 111 d following application of AS or CT sealcoat. Concentrations of the sum of 16 PAHs (median concentrations of 328 and 35 μg/L for CT and AS runoff, respectively) in runoff varied relatively little, but rapid decreases in concentrations of azaarenes and low molecular weight PAHs were offset by increases in high molecular weight PAHs. The results demonstrate that runoff from CT-sealcoated pavement, in particular, continues to contain elevated concentrations of PAHs long after a 24-h curing time, with implications for the fate, transport, and ecotoxicological effects of contaminants in runoff from CT-sealcoated pavement.

Using the Sacramento soil moisture accounting model to provide short-term forecasts of surface runoff for daily decision making in nutrient management

USDA-ARS?s Scientific Manuscript database

Managing the timing of fertilizer and manure application is critical to protecting water quality in agricultural watersheds. When fertilizers and manures are applied at inopportune times (e.g., just prior to a rainfall event that produces surface runoff) the risk of surface water contamination is un...

Assessment of Water Quality of Runoff from Sealed Asphalt Surfaces

EPA Science Inventory

This report discusses the results of runoff tests from recently-sealed asphalt surfaces conducted at EPA's Urban Watershed Research Facility (UWRF) in Edison, New Jersey. Both bench-scale panels and full-scale test plots were evaluated. Full-scale tests were performed on an asp...

Sorption, Leaching, and Surface Runoff of Beef Cattle Veterinary Pharmaceuticals under Simulated Irrigated Pasture Conditions.

PubMed

Popova, Inna E; Bair, Daniel A; Tate, Kenneth W; Parikh, Sanjai J

2013-07-01

The use of veterinary pharmaceuticals in beef cattle has led to concerns associated with the development of antibiotic resistance in bacteria and endocrine disruption in aquatic organisms. Despite the potential negative consequences, data on the transport and mitigation of pharmaceuticals in grazed watersheds with irrigated pasture are scarce. The objective of this study was to assess the transport of common beef cattle pharmaceuticals (oxytetracycline, chlortetracycline, and ivermectin) via surface runoff and leachate from manure amended to grass-vegetated soil boxes under irrigated pasture conditions. The transport of pharmaceuticals from animal manure in surface runoff and soil leachate was relatively low and appears to be limited by desorption and transport of pharmaceuticals entrained in the manure. In surface runoff, less than 4.2% of applied pharmaceuticals in manure (initial concentration: 0.2 mg kg of manure) was detected after 3 wk of irrigation. Concentrations of pharmaceuticals in surface runoff and leachate never exceeded 0.5 μg L. The major portion of pharmaceuticals (up to 99%) was retained in the manure or in the soil directly beneath the manure application site. Based on the minimal transport of oxytetracycline, chlortetracycline, and ivermectin, the risk of significant transport for these targeted beef cattle pharmaceuticals to surface water and groundwater from manure on irrigated pasture appears to be relatively low. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Antibiotic losses in leaching and surface runoff from manure-amended agricultural land.

PubMed

Dolliver, Holly; Gupta, Satish

2008-01-01

A 3-yr field study quantified leaching and runoff losses of antibiotics from land application of liquid hog (chlortetracycline and tylosin) and solid beef (chlortetracycline, monensin, and tylosin) manures under chisel plowing and no-tillage systems. The study was conducted in southwestern Wisconsin, a karst area with steep, shallow, macroporous soils. Relative mass losses of chlortetracycline, monensin, and tylosin were <5% of the total amount applied with manure. Chlortetracycline was only detected in runoff, whereas monensin and tylosin were detected in leachate and runoff. Highest concentrations of monensin and tylosin in the leachate were 40.9 and 1.2 microg L(-1), respectively. Highest chlortetracycline, monensin, and tylosin concentrations in runoff were 0.5, 57.5, and 6.0 microg L(-1), respectively. For all three antibiotics, >90% of detections and 99% of losses occurred during the non-growing season due to fall manure application and slow degradation of antibiotics at cold temperatures. During years of high snowmelt, runoff accounted for nearly 100% of antibiotic losses, whereas during years of minimal snowmelt, runoff accounted for approximately 40% of antibiotic losses. Antibiotic losses were generally higher from the no-tillage compared with chisel plow treatment due to greater water percolation as a result of macroporosity and greater runoff due to lack of surface roughness in the no-tillage plots during the non-growing season. The results from this study suggest that small quantities of dissolved antibiotics could potentially reach surface and ground waters in the Upper Midwestern USA from manure-amended shallow macroporous soils underlain with fractured bedrock.

Effects of climate and land cover on hydrology in the southeastern U.S.: Potential impacts on watershed planning

USGS Publications Warehouse

LaFontaine, Jacob H.; Hay, Lauren E.; Viger, Roland; Regan, R. Steve; Markstrom, Steven

2015-01-01

The hydrologic response to statistically downscaled general circulation model simulations of daily surface climate and land cover through 2099 was assessed for the Apalachicola-Chattahoochee-Flint River Basin located in the southeastern United States. Projections of climate, urbanization, vegetation, and surface-depression storage capacity were used as inputs to the Precipitation-Runoff Modeling System to simulate projected impacts on hydrologic response. Surface runoff substantially increased when land cover change was applied. However, once the surface depression storage was added to mitigate the land cover change and increases of surface runoff (due to urbanization), the groundwater flow component then increased. For hydrologic studies that include projections of land cover change (urbanization in particular), any analysis of runoff beyond the change in total runoff should include effects of stormwater management practices as these features affect flow timing and magnitude and may be useful in mitigating land cover change impacts on streamflow. Potential changes in water availability and how biota may respond to changes in flow regime in response to climate and land cover change may prove challenging for managers attempting to balance the needs of future development and the environment. However, these models are still useful for assessing the relative impacts of climate and land cover change and for evaluating tradeoffs when managing to mitigate different stressors.

Response Characteristics of Dissolved Organic Carbon Flushing in a Subarctic Alpine Catchment

NASA Astrophysics Data System (ADS)

Carey, S. K.

2002-12-01

Dissolved organic carbon (DOC) is an important part of ecosystem-scale carbon balances and in the transport of contaminants as it interacts with other dissolved substances including trace metals. It also can be used as a surrogate hydrological tracer in permafrost regions as near-surface waters are often DOC enriched due to the presence of thick organic soils. In a small subarctic alpine catchment within the Wolf Creek Research Basin, Yukon, Canada, DOC was studied in the summer of 2001 and spring of 2002 to determine the role frost (both permanent and seasonal), snowmelt and summer storms on DOC flushing. Peak DOC concentrations occurred during the snowmelt period, approximately one week prior to peak discharge. However, peak discharge took place several weeks after snow on south facing exposures had melted. Within the hillslopes, DOC concentrations were three to five times greater in wells underlain with permafrost compared with seasonal frost. Groundwater DOC concentrations declined during snowmelt, yet remained at levels above the streamflow. After peaking, streamflow DOC concentrations declined exponentially suggesting a simple flushing mechanism, however there did not appear to be a relation between DOC and topographic position. Following melt, permafrost underlain slopes had near-surface water tables and retained elevated levels of DOC, whereas slopes without permafrost had rapidly declining water tables at upslope locations with low DOC concentrations at all positions except near-stream riparian zones. The influence of summer rainstorms on DOC was monitored on three occasions. In each case DOC peaked on the ascending limb of the runoff hydrograph and declined exponentially on the receding limb and hysteretic behavior occurred between discharge and DOC during all events. Patterns of DOC within the hillslopes and streams suggest that runoff from permafrost-underlain slopes control DOC flushing within the stream during both snowmelt and summer periods. This flushing mechanism conforms with conceptual models of runoff generation in discontinuous permafrost catchments whereby water tables within permafrost-underlain slopes rise into porous organic-layers, whereupon DOC is leached into the water and rapidly conveyed to the stream.

Erosivity, surface runoff, and soil erosion estimation using GIS-coupled runoff-erosion model in the Mamuaba catchment, Brazil.

PubMed

Marques da Silva, Richarde; Guimarães Santos, Celso Augusto; Carneiro de Lima Silva, Valeriano; Pereira e Silva, Leonardo

2013-11-01

This study evaluates erosivity, surface runoff generation, and soil erosion rates for Mamuaba catchment, sub-catchment of Gramame River basin (Brazil) by using the ArcView Soil and Water Assessment Tool (AvSWAT) model. Calibration and validation of the model was performed on monthly basis, and it could simulate surface runoff and soil erosion to a good level of accuracy. Daily rainfall data between 1969 and 1989 from six rain gauges were used, and the monthly rainfall erosivity of each station was computed for all the studied years. In order to evaluate the calibration and validation of the model, monthly runoff data between January 1978 and April 1982 from one runoff gauge were used as well. The estimated soil loss rates were also realistic when compared to what can be observed in the field and to results from previous studies around of catchment. The long-term average soil loss was estimated at 9.4 t ha(-1) year(-1); most of the area of the catchment (60%) was predicted to suffer from a low- to moderate-erosion risk (<6 t ha(-1) year(-1)) and, in 20% of the catchment, the soil erosion was estimated to exceed > 12 t ha(-1) year(-1). Expectedly, estimated soil loss was significantly correlated with measured rainfall and simulated surface runoff. Based on the estimated soil loss rates, the catchment was divided into four priority categories (low, moderate, high and very high) for conservation intervention. The study demonstrates that the AvSWAT model provides a useful tool for soil erosion assessment from catchments and facilitates the planning for a sustainable land management in northeastern Brazil.

Rainfall-runoff model for prediction of waterborne viral contamination in a small river catchment

NASA Astrophysics Data System (ADS)

Gelati, E.; Dommar, C.; Lowe, R.; Polcher, J.; Rodó, X.

2013-12-01

We present a lumped rainfall-runoff model aimed at providing useful information for the prediction of waterborne viral contamination in small rivers. Viral contamination of water bodies may occur because of the discharge of sewage effluents and of surface runoff over areas affected by animal waste loads. Surface runoff is caused by precipitation that cannot infiltrate due to its intensity and to antecedent soil water content. It may transport animal feces to adjacent water bodies and cause viral contamination. We model streamflow by separating it into two components: subsurface flow, which is produced by infiltrated precipitation; and surface runoff. The model estimates infiltrated and non-infiltrated precipitation and uses impulse-response functions to compute the corresponding fractions of streamflow. The developed methodologies are applied to the Glafkos river, whose catchment extends for 102 km2 and includes the city of Patra. Streamflow and precipitation observations are available at a daily time resolution. Waterborne virus concentration measurements were performed approximately every second week from the beginning of 2011 to mid 2012. Samples were taken at several locations: in river water upstream of Patras and in the urban area; in sea water at the river outlet and approximately 2 km south-west of Patras; in sewage effluents before and after treatment. The rainfall-runoff model was calibrated and validated using observed streamflow and precipitation data. The model contribution to waterborne viral contamination prediction was benchmarked by analyzing the virus concentration measurements together with the estimated surface runoff values. The presented methodology may be a first step towards the development of waterborne viral contamination alert systems. Predicting viral contamination of water bodies would benefit sectors such as water supply and tourism.

Water table variability and runoff generation in an eroded peatland, South Pennines, UK

NASA Astrophysics Data System (ADS)

Daniels, S. M.; Agnew, C. T.; Allott, T. E. H.; Evans, M. G.

2008-10-01

SummaryHydrological monitoring in an eroded South Pennine peatland shows that persistent and frequent water table drawdowns occur at gully edge locations, defining a deeper and thicker acrotelm than is observed in intact peatlands (an erosional acrotelm). Antecedent water table elevation is a key control on the hydrological response to precipitation events, in particular runoff percent, the timing of peak discharges and maximum water table elevations. Significant discharge is generated whilst water table elevations are relatively low at gully edge locations, and this has a strong influence on flow pathways. Four characteristics of runoff response are recognised: (i) the rapid development of macropore/pipe flow at the start of the storm; (ii) peat rewetting, water table elevation increase and continued macropore/pipe flow; (iii) maximum water table elevations and peak stream discharge with throughflow occurring within the erosional acrotelm and rapid flow through the subsurface macropore/pipe network; (iv) rapidly declining water table elevations and stream flow following the cessation of rainfall. Gully edge peats provide a key linkage between the hillslope hydrological system and channel flow so that their influence on the hydrological functioning of the peatlands is disproportionate to their aerial extent within the catchment. Future climate change may lead to further degradation of the bogs and a reinforcement of the importance of erosion gullies to runoff generation and water quality.

Frijolito Watershed: Integrated investigations of a rapidly eroding pinyon-juniper hillslope

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilcox, B.P.; Pitlick, J.; Allen, C.D.

1995-12-31

The dramatic acceleration of erosion associated with the expansion of pinyon-juniper woodlands over the past 100 years has been widely recognized, but few process-based studies of this phenomenon have been undertaken. In an attempt to identify the underlying causes, and the factors that affect erosion processes, we have initiated an interdisciplinary study of a rapidly eroding pinyon-juniper woodland in northern New Mexico. Since July 1993, we have collected data on runoff, erosion, and weather conditions from a 1-ha catchment study area and have conducted surveys of topography, soils, and vegetation. Our preliminary results indicate that although runoff makes up lessmore » than 10% of the annual water budget, runoff events - which are frequent in the summer - are capable of moving large amounts of sediment. We estimate that between July 1993 and October 1994, between 25,000 and 50,000 kg of sediment has eroded and been transported from the catchment. The information gained from such studies is essential to our ability to formulate effective strategies for managing these rapidly eroding woodlands.« less

Spatio-temporal patterns in land use and management affecting surface runoff response of agricultural catchments - a review

NASA Astrophysics Data System (ADS)

Fiener, P.; Auerswald, K.; van Oost, K.

2009-04-01

In many landscapes, land use creates a complex pattern in addition to the patterns resulting from soil, topography and rain. Despite the static layout of fields, a spatio-temporally highly variable situation regarding the surface runoff and erosion processes results from the asynchronous seasonal variation associated with different land uses. While the behaviour of individual land-uses and their seasonal variation is analyzed in many studies, the spatio-temporal interaction related to this pattern is rarely studied despite its crucial influence on hydrological and geomorphic response of catchments. The difficulty in studying such interactions mainly results from the fact that it is impossible to set up a replicated experiment on the landscape scale. The purpose of this review is to present the advances made thus far in quantifying the effects of patchiness of land use and management on surface runoff response in agricultural catchments. We will focus on the effects of spatio-temporal patterns in land use patches on hydraulic connectivity between patches and within catchments. This will include the temporal patterns in land management affecting infiltration, surface roughness and hence runoff concentration within single fields or land use patches insofar as these effects must be known to evaluate the combined effect of patch behaviour in space and time on catchment connectivity and surface runoff. Surface runoff effects of patchiness and connectivity between patches or within a catchment, can either be addressed by modelling studies or by comprehensive catchment field measurements, e.g. paired-watershed experiments or landscape scale studies on different scales. This limits our review to studies at the scale of small catchments < 10 km², where the time constant of the network (i.e. travel time through it) is smaller than the infiltration phase. Despite this limitation, these small catchments are important as they constitute 2/3 of the total surface of large water drainage networks.

A protocol for conducting rainfall simulation to study soil runoff

USDA-ARS?s Scientific Manuscript database

Rainfall is a driving force for the transport of environmental contaminants from agricultural soils to surficial water bodies via surface runoff. The objective of this study was to characterize the effects of antecedent soil moisture content on the fate and transport of surface applied commercial ur...

40 CFR 440.42 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2010 CFR

2010-07-01

... annual precipitation falling on the treatment facility and the drainage area contributing surface runoff... difference between annual precipitation falling on the treatment facility and the drainage area contributing surface runoff to the treatment facility and annual evaporation may be discharged subject to the...

A point-infiltration model for estimating runoff from rainfall on small basins in semiarid areas of Wyoming

USGS Publications Warehouse

Rankl, James G.

1990-01-01

A physically based point-infiltration model was developed for computing infiltration of rainfall into soils and the resulting runoff from small basins in Wyoming. The user describes a 'design storm' in terms of average rainfall intensity and storm duration. Information required to compute runoff for the design storm by using the model include (1) soil type and description, and (2) two infiltration parameters and a surface-retention storage parameter. Parameter values are tabulated in the report. Rainfall and runoff data for three ephemeral-stream basins that contain only one type of soil were used to develop the model. Two assumptions were necessary: antecedent soil moisture is some long-term average, and storm rainfall is uniform in both time and space. The infiltration and surface-retention storage parameters were determined for the soil of each basin. Observed rainstorm and runoff data were used to develop a separation curve, or incipient-runoff curve, which distinguishes between runoff and nonrunoff rainfall data. The position of this curve defines the infiltration and surface-retention storage parameters. A procedure for applying the model to basins that contain more than one type of soil was developed using data from 7 of the 10 study basins. For these multiple-soil basins, the incipient-runoff curve defines the infiltration and retention-storage parameters for the soil having the highest runoff potential. Parameters were defined by ranking the soils according to their relative permeabilities and optimizing the position of the incipient-runoff curve by using measured runoff as a control for the fit. Analyses of runoff from multiple-soil basins indicate that the effective contributing area of runoff is less than the drainage area of the basin. In this study, the effective drainage area ranged from 41.6 to 71.1 percent of the total drainage area. Information on effective drainage area is useful in evaluating drainage area as an independent variable in statistical analyses of hydrologic data, such as annual peak frequency distributions and sediment yield.A comparison was made of the sum of the simulated runoff and the sum of the measured runoff for all available records of runoff-producing storms in the 10 study basins. The sums of the simulated runoff ranged from 12.0 percent less than to 23.4 percent more than the sums of the measured runoff. A measure of the standard error of estimate was computed for each data set. These values ranged from 20 to 70 percent of the mean value of the measured runoff. Rainfall-simulator infiltrometer tests were made in two small basins. The amount of water uptake measured by the test in Dugout Creek tributary basin averaged about three times greater than the amount of water uptake computed from rainfall and runoff data. Therefore, infiltrometer data were not used to determine infiltration rates for this study.

Evaluation of agricultural best-management practices in the Conestoga River headwaters, Pennsylvania : characterization of surface-runoff and ground-water quantity and quality in a small carbonate basin near Churchtown, Pennsylvania, prior to terracing and implementation of nutrient management : water-quality study of the Conestoga River headwaters, Pennsylvania

USGS Publications Warehouse

Leitman, Patricia L.; Hall, D.W.; Langland, M.J.; Chichester, D.C.; Ward, J.R.

1996-01-01

Surface-runoff and ground-water quantity and quality of a 22.1-acre field site were characterized from January 1983 through September 1984, before implementation of terracing and nutrient-management practices. The site, underlain by carbonate rock, was cropland used primarily for the production of corn and alfalfa. Average annual application of nutrients to the 14.4 acres of cornfields was 410 pounds of nitrogen and 110 pounds of phosphorus. About three times more nutrients were applied during the 1984 water year than during the 1983 water year. During the investigation, 714,000 cubic feet of runoff transported 244 tons of suspended sediment, 300 pounds of nitrogen, and 170 pounds of phosphorus during the 1984 water year. Runoff from storms on frozen ground produced the highest loads of nitrogen. Regression analyses indicate that runoff rates and quantities were controlled by precipitation intensities of quantities and the amount of crop cover, and that mean concentrations of nitrogen for runoff events increased with increased surface-nitrogen applications made prior to runoff. Ground-water levels responded quickly to recharge, with peaks occurring several hours to a day after precipitation. Median concentrations of dissolved nitrate in ground water ranged from 9.2 to 13 milligrams per liter as nitrogen. A lag time of 1 to 3 months was observed between the time that nitrogen was applied to the land surface and local maximums in nitrate concentrations were detected in ground water unaffected by recharge events. About 3 million cubic feet of ground water and an associated 2,200 pounds of nitrate-nitrogen discharged from the site during the study period. For the study period, 42 percent of the precipitation recharged to ground water, 10 percent became runoff, and 48 percent evapotranspired. Inputs of nitrogen to the study area were estimated to be 93 percent from manure, 5 percent from commercial fertilizer, and 2 percent from precipitation. Nitrogen outputs from the system were estimated to be 38 percent to crop uptake, 39 percent to volatilization, 20 percent to ground- water discharge, and 3 percent to surface runoff.

Modeling spray drift and runoff-related inputs of pesticides to receiving water.

PubMed

Zhang, Xuyang; Luo, Yuzhou; Goh, Kean S

2018-03-01

Pesticides move to surface water via various pathways including surface runoff, spray drift and subsurface flow. Little is known about the relative contributions of surface runoff and spray drift in agricultural watersheds. This study develops a modeling framework to address the contribution of spray drift to the total loadings of pesticides in receiving water bodies. The modeling framework consists of a GIS module for identifying drift potential, the AgDRIFT model for simulating spray drift, and the Soil and Water Assessment Tool (SWAT) for simulating various hydrological and landscape processes including surface runoff and transport of pesticides. The modeling framework was applied on the Orestimba Creek Watershed, California. Monitoring data collected from daily samples were used for model evaluation. Pesticide mass deposition on the Orestimba Creek ranged from 0.08 to 6.09% of applied mass. Monitoring data suggests that surface runoff was the major pathway for pesticide entering water bodies, accounting for 76% of the annual loading; the rest 24% from spray drift. The results from the modeling framework showed 81 and 19%, respectively, for runoff and spray drift. Spray drift contributed over half of the mass loading during summer months. The slightly lower spray drift contribution as predicted by the modeling framework was mainly due to SWAT's under-prediction of pesticide mass loading during summer and over-prediction of the loading during winter. Although model simulations were associated with various sources of uncertainties, the overall performance of the modeling framework was satisfactory as evaluated by multiple statistics: for simulation of daily flow, the Nash-Sutcliffe Efficiency Coefficient (NSE) ranged from 0.61 to 0.74 and the percent bias (PBIAS) < 28%; for daily pesticide loading, NSE = 0.18 and PBIAS = -1.6%. This modeling framework will be useful for assessing the relative exposure from pesticides related to spray drift and runoff in receiving waters and the design of management practices for mitigating pesticide exposure within a watershed. Published by Elsevier Ltd.

[Pollution Characteristics of Surface Runoff of Typical Town in Chongqing City].

PubMed

Wang, Long-tao; Duan, Bing-zheng; Zhao, Jian-wei; Hua, Yu-mei; Zhu, Duan-wei

2015-08-01

Six kinds of impermeable underlying surface, cement tile roof, asbestos roof, cement flat roof, residential concrete pavement, asphalt pavement of restaurants, asphalt pavement of oil depot, and a combined sewer overflow canal in the Jiansheng town of Dadukou district in Chongqing city were chosen as sample plots to study the characteristics of nutritional pollutants and heavy metals in town runoff. The research showed that the average mass concentrations of TSS, COD, TN, TP in road runoff were (1681.2 +/- 677.2), (1154.7 +/- 415.5), (12.07 +/- 2.72), (3.32 +/- 1.15) mgL(-1), respectively. These pollutants were higher than those in roof runoff which were (13.3 +/- 6.5), (100.4 +/- 24.8), (3.58 +/- 0.70), (0.10 +/- 0.02) mg x L(-1), respectively. TDN accounted for 62.60% +/- 34.38% of TN, and TDP accounted for 42.22% +/- 33.94% of TP in the runoff of impermeable underlying surface. Compared with the central urban runoff, town runoff in our study had higher mass concentrations of these pollutants. The mass concentrations of TSS, COD, TDN, TN, TDP and TP in the combined sewer overflow were (281.57 +/- 308.38), (231.21 +/- 42.95), (8.16 +/- 2.78), (10.60 +/- 3.94), (0.38 +/- 0.23) and (1.51 +/- 0.75) mg x L(-1), respectively. The average levels of heavy metals in this kind of runoff did not exceed the class VI level of the surface water environmental quality standard. Most pollutants in the combined sewer overflow had first flush. However, this phenomenon was very rare for TSS. There was a significant positive correlation between TSS and COD, TP in the combined sewer overflow. And this correlation was significant between NH4+ -N and TP, TDP, TN, TDP. However, a negative correlation existed between NO3- -N and all other indicators.

Effects of near-surface hydraulic gradients on nitrate and phosphorus losses in surface runoff.

PubMed

Zheng, Fen-Li; Huang, Chi-Hua; Norton, L Darrell

2004-01-01

Phosphorous (P) and nitrogen (N) in runoff from agricultural fields are key components of nonpoint-source pollution and can accelerate eutrophication of surface waters. A laboratory study was designed to evaluate effects of near-surface hydraulic gradients on P and N losses in surface runoff from soil pans at 5% slope under simulated rainfall. Experimental treatments included three rates of fertilizer input (control [no fertilizer input], low [40 kg P ha(-1), 100 kg N ha(-1)], and high [80 kg P ha(-1), 200 kg N ha(-1)]) and four near-surface hydraulic gradients (free drainage [FD], saturation [Sa], artesian seepage without rain [Sp], and artesian seepage with rain [Sp + R]). Simulated rainfall of 50 mm h(-1) was applied for 90 min. The results showed that near-surface hydraulic gradients have dramatic effects on NO(3)-N and PO(4)-P losses and runoff water quality. Under the low fertilizer treatment, the average concentrations in surface runoff from FD, Sa, Sp, and Sp + R were 0.08, 2.20, 529.5, and 71.8 mg L(-1) for NO(3)-N and 0.11, 0.54, 0.91, and 0.72 mg L(-1) for PO(4)-P, respectively. Similar trends were observed for the concentrations of NO(3)-N and PO(4)-P under the high fertilizer treatment. The total NO(3)-N loss under the FD treatment was only 0.01% of the applied nitrogen, while under the Sp and Sp + R treatments, the total NO(3)-N loss was 11 to 16% of the applied nitrogen. These results show that artesian seepage could make a significant contribution to water quality problems.

Effect of vegetation construction on runoff and sediment yield and runoff erosion ability on slope surface

NASA Astrophysics Data System (ADS)

Yang, Chun Xia; Xiao, PeiQing; Li, Li; Jiao, Peng

2018-06-01

Land consolidation measures affected the underlying surface erosion environment during the early stage of vegetation construction, and then had an impact on rainfall infiltration, erosion and sediment yield. This paper adopted the field simulated rainfall experiments to analyze the function that pockets site preparation measures affected on rainfall infiltration, runoff sediment yield and runoff erosion ability. The results showed that, the measures can delay the rainfall runoff formation time of the slope by 3'17" and 1'04" respectively. Compared with the same condition of the bare land and natural grassland. The rainfall infiltration coefficient each increased by 76.47% and 14.49%, and infiltration rate increased by 0.26 mm/min and 0.11mm/min respectively; The amount of runoff and sediment yield were reduced because of the pockets site preparation. The amount of runoff reducing rate were 33.51% and 30.49%, and sediment reduction rate were 81.35% and 65.66%, The sediment concentration was decreased by 71.99% and 50.58%; Runoff velocity of bare slope and natural grassland slope decreased by 38.12% and 34.59% respectively after pockets site preparation . The runoff erosion rate decreased by 67.92% and 79.68% respectively. The results will have a great significance for recognizing the effect of water and sediment reduction about vegetation and the existence of its plowing measures at the early period of restoration.

Estimating pesticide runoff in small streams.

PubMed

Schriever, Carola A; von der Ohe, Peter C; Liess, Matthias

2007-08-01

Surface runoff is one of the most important pathways for pesticides to enter surface waters. Mathematical models are employed to characterize its spatio-temporal variability within landscapes, but they must be simple owing to the limited availability and low resolution of data at this scale. This study aimed to validate a simplified spatially-explicit model that is developed for the regional scale to calculate the runoff potential (RP). The RP is a generic indicator of the magnitude of pesticide inputs into streams via runoff. The underlying runoff model considers key environmental factors affecting runoff (precipitation, topography, land use, and soil characteristics), but predicts losses of a generic substance instead of any one pesticide. We predicted and evaluated RP for 20 small streams. RP input data were extracted from governmental databases. Pesticide measurements from a triennial study were used for validation. Measured pesticide concentrations were standardized by the applied mass per catchment and the water solubility of the relevant compounds. The maximum standardized concentration per site and year (runoff loss, R(Loss)) provided a generalized measure of observed pesticide inputs into the streams. Average RP explained 75% (p<0.001) of the variance in R(Loss). Our results imply that the generic indicator can give an adequate estimate of runoff inputs into small streams, wherever data of similar resolution are available. Therefore, we suggest RP for a first quick and cost-effective location of potential runoff hot spots at the landscape level.

Comparison between snowmelt-runoff and rainfall-runoff nonpoint source pollution in a typical urban catchment in Beijing, China.

PubMed

Chen, Lei; Zhi, Xiaosha; Shen, Zhenyao; Dai, Ying; Aini, Guzhanuer

2018-01-01

As a climate-driven event, nonpoint source (NPS) pollution is caused by rainfall- or snowmelt-runoff processes; however, few studies have compared the characteristics and mechanisms of these two kinds of NPS processes. In this study, three factors relating to urban NPS, including surface dust, snowmelt, and rainfall-runoff processes, were analyzed comprehensively by both field sampling and laboratory experiments. The seasonal variation and leaching characteristics of pollutants in surface dust were explored, and the runoff quality of snowmelt NPS and rainfall NPS were compared. The results indicated that dusts are the main sources of urban NPS and more pollutants are deposited in dust samples during winter and spring. However, pollutants in surface dust showed a low leaching ratio, which indicated most NPS pollutants would be carried as particulate forms. Compared to surface layer, underlying snow contained higher chemical oxygen demand, total suspended solids (TSS), Cu, Fe, Mn, and Pb concentrations, while the event mean concentration of most pollutants in snowmelt tended to be higher in roads. Moreover, the TSS and heavy metal content of snowmelt NPS was always higher than those of rainfall NPS, which indicated the importance of controlling snowmelt pollution for effective water quality management.

Increasing Freshwater Runoff and Tidal Action Influences on Spatial Mixing Patterns in Søndre Strømfjord, West Greenland

NASA Astrophysics Data System (ADS)

Smiley, C. R.; Kamenos, N.; Hoey, T.; Cottier, F.; Ellam, R. M.

2014-12-01

Greenland Ice Sheet melt has the potential to affect global sea levels and the strength of the thermohaline circulation (THC). Investigating spatial mixing patterns of seawater in Greenlandic fjords can help reveal characteristics of changes in runoff from the GrIS; for example higher runoff may be associated with lower salinity within GrIS fjords, which can be recorded by palaeoenvironmental proxies (Kamenos et al 2012). The Kangerlussuaq Drainage Basin mirrors melt patterns of the whole GrIS and drains into Søndre Strømfjord, a 170km long fjord on the west coast of Greenland. Temperature and salinity profiles to 40m depth were obtained at 11 stations along Søndre Strømfjord during the 2014 melt season. Each station was sampled twice once at high KDB runoff and once at low KDB runoff. With increasing freshwater runoff, salinity decreases by 1.65 - 2.91 at each station over a 7 hour time period. Higher salinities occur at low run-off. In addition, with increasing run-off, the disparity between surface and deeper water (30m) becomes greater with a 19.3 difference between the surface and 30m. With higher KDB runoff temperature increases by 0.47oC - 2.34oC. This information will be integrated with oxygen and deuterium isotope patterns to pinpoint the exact source of the runoff causing salinity reductions. Our data show a relationship between KDB runoff and salinity of Søndre Strømfjord, data that will enable further calibration of marine proxies of GrIS melt.

Nonlinear effects of microtopography on macroscopic rainfall-runoff partitioning a the hillslope scale: a modelling study

NASA Astrophysics Data System (ADS)

Caviedes-Voullième, Daniel; Domin, Andrea; Hinz, Christoph

2017-04-01

The quantitative description and prediction of hydrological response of hillslopes or hillslope-scale catchments to rainfall events is becoming evermore relevant. At the hillslope scale, the onset of runoff and the overall rainfall-runoff transformation are controlled by multiple interacting small-scale processes, that, when acting together produce a response described in terms of hydrological variables well-defined at the catchment and hillslope scales. We hypothesize that small scale features such microtopography of the land surface will will govern large scale signatures of temporal runoff evolution. This can be tested directly by numerical modelling of well-defined surface geometries and adequate process description. It requires a modelling approach consistent with fundamental fluid mechanics, well-designed numerical methods, and computational efficiency. In this work, an idealized rectangular domain representing a hillslope with an idealized 2D sinusoidal microtopography is studied by simulating surface water redistribution by means of a 2D diffusive-wave (zero-inertia) shallow water model. By studying more than 500 surfaces and performing extensive sensitivity analysis forced by a single rainfall pulse, the dependency of characteristic hydrological responses to microtopographical properties was assessed. Despite of the simplicity of periodic surface and the rain event, results indicate complex surface flow dynamics during the onset of runoff observed at the macro and micro scales. Macro scale regimes were defined in terms of characteristics hydrograph shapes and those were related to surface geometry. The reference regime was defined for smooth topography and consisted of a simple hydrograph with smoothly rising and falling limbs with an intermediate steady state. In constrast, rough surface geometry yields stepwise rising limbs and shorter steady states. Furthermore, the increase in total infiltration over the whole domain relative to the smooth reference case shows a strong non-linear dependency on slope and the ratio of the characteristic wavelength and amplitude of microtopography. The coupled analysis of spatial and hydrological results also suggests that the hydrological behaviour can be explained by the spatiotemporal variations triggered by surface connectivity. This study significantly extents previous work on 1D domains, as our results reveal complexities that require 2D representation of the runoff processes.

Smoothed Particle Hydrodynamics Modeling of Gravity Currents on a Dry Porous Medium

NASA Astrophysics Data System (ADS)

Daly, E.; Grimaldi, S.; Bui, H.

2014-12-01

Gravity currents flowing over porous media occur in many environmental processes and industrial applications, such as irrigation, benthic boundary layers, and oil spills. The coupling of the flow over the porous surface and the infiltration of the fluid in the porous media is complex and difficult to model. Of particular interest is the prediction of the position of the runoff front and the depth of the infiltration front. We present here a model for the flow of a finite volume of a highly viscous Newtonian fluid over a dry, homogenous porous medium. The Navier-Stokes equations describing the runoff flow are coupled to the Volume Averaged Navier-Stokes equations for the infiltration flow. The numerical solution of these equations is challenging because of the presence of two free surfaces (runoff and infiltration waves), the lack of fixed boundary conditions at the runoff front, and the difficulties in defining appropriate conditions at the surface of the porous medium. The first two challenges were addressed by using Smoothed Particle Hydrodynamics, which is a Lagrangian, mesh-free particle method particularly suitable for modelling free surface flows. Two different approaches were used to model the flow conditions at the surface of the porous medium. The Two Domain Approach (TDA) assumes that runoff and infiltration flows occur in two separate homogenous domains; here, we assume the continuity of velocity and stresses at the interface of the two domains. The One Domain Approach (ODA) models runoff and infiltration flows as occurring through a medium whose hydraulic properties vary continuously in space. The transition from the hydraulic properties of the atmosphere and the porous medium occur in a layer near the surface of the porous medium. Expressions listed in literature were used to compute the thickness of this transition layer and the spatial variation of porosity and permeability within it. Our results showed that ODA led to slower velocities of the runoff front and enhanced infiltration when compared to the implemented formulation of TDA. In the ODA, depending on the description of the transition layer, the maximum distances travelled by the runoff front and the maximum depth of infiltration varied over a range of ±15% and ±50% when compared to their respective averaged values.

Evaluation of core cultivation practices to reduce ecological risk of pesticides in runoff from turf

USDA-ARS?s Scientific Manuscript database

Pesticides associated with the turfgrass industry have been detected in storm runoff and surface waters of urban watersheds; raising concern of their potential environmental effects and a desire to reduce their transport to non-target locations. Runoff studies were conducted to compare the effective...

Laboratory Simulation of Urban Runoff and Estimation of Runoff Hydrographs with Experimental Curve Numbers Implemented in USEPA SWMM

EPA Science Inventory

The prognostic capabilities of a lumped hydrologic modeling approach may be complicated by routing and connectivity among infiltrative and impervious surfaces. We used artificial rainfall to generate runoff from impervious and bare soil boxes arranged in series to simulate differ...

Responses of hydrochemical inorganic ions in the rainfall-runoff processes of the experimental catchments and its significance for tracing

USGS Publications Warehouse

Gu, W.-Z.; Lu, J.-J.; Zhao, X.; Peters, N.E.

2007-01-01

Aimed at the rainfall-runoff tracing using inorganic ions, the experimental study is conducted in the Chuzhou Hydrology Laboratory with special designed experimental catchments, lysimeters, etc. The various runoff components including the surface runoff, interflow from the unsaturated zone and the groundwater flow from saturated zone were monitored hydrometrically. Hydrochemical inorganic ions including Na+, K+, Ca2+, Mg2+, Cl-, SO42-, HCO3- + CO32-, NO3-, F-, NH4-, PO42-, SiO2 and, pH, EC, 18O were measured within a one month period for all processes of rainfall, various runoff components and groundwater within the catchment from 17 boreholes distributed in the Hydrohill Catchment, few soil water samples were also included. The results show that: (a) all the runoff components are distinctly identifiable from both the relationships of Ca2+ versus Cl-/SO42-, EC versus Na+/(Na+ + Ca2+) and, from most inorganic ions individually; (b) the variation of inorganic ions in surface runoff is the biggest than that in other flow components; (c) most ions has its lowermost concentration in rainfall process but it increases as the generation depths of runoff components increased; (d) quantitatively, ion processes of rainfall and groundwater flow display as two end members of that of other runoff components; and (e) the 18O processes of rainfall and runoff components show some correlation with that of inorganic ions. The results also show that the rainfall input is not always the main source of inorganic ions of various runoff outputs due to the process of infiltration and dissolution resulted from the pre-event processes. The amount and sources of Cl- of runoff components with various generation mechanisms challenge the current method of groundwater recharge estimation using Cl-.

Fertilizer-derived uranium and sulfur in rangeland soil and runoff: A case study in central Florida

USGS Publications Warehouse

Zielinski, R.A.; Orem, W.H.; Simmons, K.R.; Bohlen, P.J.

2006-01-01

Fertilizer applications to rangeland and pastures in central Florida have potential impact on the nutrient-sensitive ecosystems of Lake Okeechobee and the Northern Everglades. To investigate the effects of fertilizer applications, three soil profiles from variably managed and improved rangeland, and four samples of surface runoff from both fertilized and unfertilized pasture were collected. In addition to determining nutrient concentrations, isotopic analyses of uranium (U) and sulfur (S) were performed to provide isotopic evidence for U derived from historically applied phosphate (P)-bearing fertilizer ( 234 U 238U activity ratio =1.0 ?? 0.05), and Sderived from recently applied ammonium sulfate fertilizer(??34 S=3.5permil).The distribution and mobility of fertilizer-derived U in these samples is considered to be analogous to that of fertilizer-derived phosphate.Variations of U concentrations and 234 U/238 U activity ratios in soils indicate contribution of fertilizer-derived U in the upper portions of the fertilized soil (15-}34 percent of total U). The U isotope data for runoff from the fertilized field also are consistent with some contribution from fertilizer-derived U. Parallel investigations of S showed no consistent chemical or isotopic evidence for significant fertilizer-derived sulfate in rangeland soil or runoff. Relatively abundant and isotopically variable S present in the local environment hinders detection of fertilizer-derived sulfate. The results indicate a continuing slow-release of fertilizer-derived U and, by inference, P, to the P-sensitive ecosystem, and a relatively rapid release of sulfate of possible natural origin. ?? Springer 2006.

Erosion rills offset the efficacy of vegetated buffer strips to mitigate pesticide exposure in surface waters.

PubMed

Stehle, Sebastian; Dabrowski, James Michael; Bangert, Uli; Schulz, Ralf

2016-03-01

Regulatory risk assessment considers vegetated buffer strips as effective risk mitigation measures for the reduction of runoff-related pesticide exposure of surface waters. However, apart from buffer strip widths, further characteristics such as vegetation density or the presence of erosion rills are generally neglected in the determination of buffer strip mitigation efficacies. This study conducted a field survey of fruit orchards (average slope 3.1-12.2%) of the Lourens River catchment, South Africa, which specifically focused on the characteristics and attributes of buffer strips separating orchard areas from tributary streams. In addition, in-stream and erosion rill water samples were collected during three runoff events and GIS-based modeling was employed to predict losses of pesticides associated with runoff. The results show that erosion rills are common in buffer strips (on average 13 to 24 m wide) of the tributaries (up to 6.5 erosion rills per km flow length) and that erosion rills represent concentrated entry pathways of pesticide runoff into the tributaries during rainfall events. Exposure modeling shows that measured pesticide surface water concentrations correlated significantly (R(2)=0.626; p<0.001) with runoff losses predicted by the modeling approach in which buffer strip width was set to zero at sites with erosion rills; in contrast, no relationship between predicted runoff losses and in-stream pesticide concentrations were detected in the modeling approach that neglected erosion rills and thus assumed efficient buffer strips. Overall, the results of our study show that erosion rills may substantially reduce buffer strip pesticide retention efficacies during runoff events and suggest that the capability of buffer strips as a risk mitigation tool for runoff is largely overestimated in current regulatory risk assessment procedures conducted for pesticide authorization. Copyright © 2015 Elsevier B.V. All rights reserved.

Characterisation of soil microtopography effects on runoff and soil erosion rates under simulated rainfall

USDA-ARS?s Scientific Manuscript database

Soil surface roughness is commonly identified as one of the dominant factors governing runoff and interrill erosion. Yet, because of difficulties in acquiring the data, most studies pay little attention to soil surface roughness. This is particularly true for soil erosion models which commonly don't...

Nutrient concentrations in leachate and runoff from dairy cattle lots with different surface materials

USDA-ARS?s Scientific Manuscript database

Nitrogen (N) and phosphorus (P) loss from agriculture persists as a water quality issue, and outdoor cattle lots can have a high loss potential. We monitored hydrology and nutrient concentrations in leachate and runoff from dairy heifer lots constructed with three surface materials (soil, sand, bark...

Modifying WEPP to improve streamflow simulation in a Pacific Northwest watershed

Treesearch

A. Srivastava; M. Dobre; J. Q. Wu; W. J. Elliot; E. A. Bruner; S. Dun; E. S. Brooks; I. S. Miller

2013-01-01

The assessment of water yield from hillslopes into streams is critical in managing water supply and aquatic habitat. Streamflow is typically composed of surface runoff, subsurface lateral flow, and groundwater baseflow; baseflow sustains the stream during the dry season. The Water Erosion Prediction Project (WEPP) model simulates surface runoff, subsurface lateral flow...

Evaluation of Management Practices to Mitigate Pesticide Transport and Ecological Risk of Runoff from Agricultural and Turf Systems

USDA-ARS?s Scientific Manuscript database

Highly managed biotic systems such as agricultural crops and golf courses often require multiple applications of pesticides that may be transported with runoff to surrounding surface waters. Pesticides have been detected in surface waters of rural and urban watersheds invoking concern of their sour...

Subsurface application of poultry litter and its influence on nutrient losses in runoff water from permanent pastures.

PubMed

Watts, D B; Way, T R; Torbert, H A

2011-01-01

Environmental pressure to reduce nutrient losses from agricultural fields has increased in recent years. To abate this nutrient loss to the environment, better management practices and new technologies need to be developed. Thus, research was conducted to evaluate if subsurface banding poultry litter (PL) would reduce nitrogen (N) and phosphorus (P) loss in surface water runoff using a four-row prototype implement. Rainfall simulations were conducted to create a 40-min runoff event in an established bermudagrass (Cynodon dactylon L.) pasture on soil types common to the Coastal Plain and Piedmont regions. The Coastal Plain soil type was a Marvyn loamy sand (fine-loamy, kaolinitic, thermic Typic Kanhapludults) and the Piedmont soil type was a Hard Labor loamy sand (fine, kaolinitic, thermic Oxyaquic Kanhapludults). Treatments consisted of surface- and subsurface-applied PL at a rate of 9 Mg ha(-1), surface broadcast-applied commercial fertilizer (CF; urea and triple superphosphate blend) at the equivalent N (330 kg N ha(-1)) and P (315 kg N ha(-1)) content of PL, and a nonfertilized control. The greatest loss for inorganic N, total N, dissolved reactive P (DRP), and total P occurred with the surface broadcast treatments, with CF contributing to the greatest loss. Nutrient losses from the subsurface banded treatment reduced N and P in surface water runoff to levels of the control. Subsurface banding of PL reduced concentrations of inorganic N 91%, total N 90%, DRP 86%, and total P 86% in runoff water compared with surface broadcasted PL. These results show that subsurface band-applied PL can greatly reduce the impact of N and P loss to the environment compared with conventional surface-applied PL and CF practices.

Ecohydrological Controls on Intra-Basin Alpine Subarctic Water Balances

NASA Astrophysics Data System (ADS)

Carey, S. K.; Ziegler, C. M.

2007-12-01

In the mountainous Canadian subarctic, elevation gradients control the disposition of vegetation, permafrost, and characteristics of the soil profile. How intra-basin ecosystems combine to control catchment-scale water and biogeochimcal cycling is uncertain. To this end, a multi-year ecohydrological investigation was undertaken in Granger Basin (GB), a 7.6 km2 sub-basin of the Wolf Creek Research Basin, Yukon Territory, Canada. GB was divided into four sub-basins based on the dominant vegetation and permafrost status, and the timing and magnitude of hydrological processes were compared using hydrometric and hydrochemical methods. Vegetation plays an important role in end-of-winter snow accumulation as snow redistribution by wind is controlled by roughness length. In sub-basins of GB with tall shrubs, snow accumulation is enhanced compared with areas of short shrubs and tundra vegetation. The timing of melt was staggered with elevation, although melt-rates were similar among the sub-basins. Runoff was enhanced at the expense of infiltration in tall shrub areas due to high snow water equivalent and antecedent soil moisture. In the high-elevation tundra sub-basin, thin soils with cold ground temperatures resulted in increased surface runoff. For the freshet period, the lower and upper sub-basins accounted for 81 % of runoff while accounting for 58 % of the total basin area. Two-component isotopic hydrograph separation revealed that during melt, pre-event water dominated in all sub-basins, yet those with greater permafrost disposition and taller shrubs had increased event-water. Dissolved organic carbon (DOC) spiked prior to peak freshet in each sub-basin except for the highest with thin soils, and was associated with flushing of surficial organic soils. For the post-melt period, all sub-basins have similar runoff contributions. Solute and stable isotope data indicate that in sub-basins dominated by permafrost, supra-permafrost runoff pathways predominate as flow pathways are confined above the permafrost aquitard. In contrast, lower elevation zones supply runoff via deeper subsurface flow pathways with increased levels of dissolved solutes. With regards to DOC, sub-basins dominated by permafrost supply the bulk of DOC to the stream because of near-surface pathways. Results highlight the importance of vegetation, the soil profile and frozen ground status in controlling hydrological and hydrochemical fluxes. Future changes in vegetation, which are occurring rapidly in the subarctic, are expected to have a large impact on the hydrology and biogeochemistry of these systems.

Conceptualizing the regional hydrology of a complex low relief terrain: Climate - geology interactions on sink-source dynamics of Western Boreal forests

NASA Astrophysics Data System (ADS)

Devito, K. J.; Mendoza, C. A.; Petrone, R. M.; Landhäusser, S.; Silins, U.; Qualizza, C.; Gignac, D.

2011-12-01

The Western Boreal Plain (WBP) eco-region of western Canada is experiencing unprecedented industrial development for forest, oil and gas resources, stressing the need to assess and understand the sink and source areas of regional water flow. This requires the development of models that can be use to predict and mitigate the impacts of land use changes on water quantity and quality. The WBP is characterized by low relief, hummocky terrain with complexes of forestland and wetlands, especially peatlands. A paired aspen forest harvest experiment (HEAD2) was conducted on adjacent pond-peatland-aspen forestland complexes of a moraine landform, ubiquitous throughout the WBP, to determine the influence of aspen vegetated forestlands and harvesting relative to wetlands on local and regional water cycling. Reductions in transpiration and interception following aspen harvest resulted in some increase in soil moisture. However, excess water was largely absorbed into deep moraine substrates and resulted in groundwater recharge with little or no lateral flow to adjacent wetlands and aquatic systems. As a result of high soil and groundwater storage there was no observable difference in runoff from the harvested catchment compared to the adjacent reference (uncut) catchment confirming that in most years runoff originates from the wetland (peatland) rather than forestland hydrologic units. Furthermore, soil moisture increases were short lived due to rapid redevelopment of leaf area as result of high-density regeneration of aspen through root suckering. Recovery of transpiration and interception to near pre-harvest conditions occurred within 3 years. Climate cycles, primarily inter-annual variation in snow pack, can overwhelm the influence of aspen harvest in the WBP, as during the harvest experiment large water table rises were observed in both the uncut and the harvested forestlands. This study illustrates that forestlands on deep moraine hummocky substrates of the WBP act essentially as water sinks, with large storage and exchange to the atmosphere and infrequent runoff at a regional scale. This contrasts wetland hydrologic units that contribute most frequently to regional scale runoff due to low soil storage and persistent lateral surface or near surface runoff. Mapping the organization or configuration of these two hydrological (or cryptic) units on distinct geologic landforms rather than the topographic drainage networks appears to best represent water cycling and interactions in the WBP. Using hydrologic units will facilitate better understanding and modeling of regional runoff and aid in determining the influence of geology, climate and land use interactions in heterogeneous glacial landscapes.

Impact of Landslides Induced by Earthquake on Hydrologic Response in a Mountainous Catchment

NASA Astrophysics Data System (ADS)

Qian, Q.; Su, D.; Ran, Q.

2013-12-01

The changes of the underlying surface conditions (topography, vegetation cover rate, etc.), which were caused by the numerous landslides in the Wenchuan earthquake, may influence the hydrologic response and then change the flash flood or other kinds of the disaster risk in the affected areas. The Jianpinggou catchment, located in Sichuan China, is selected as the study area for this paper. It is a steep-slope mountainous catchment, flash flood is the main disaster, and sometimes causes the debris flow. The distribution of the landslides in this catchment is obtained from the remote sensing image data. The changes of topography are obtained from the comparisons among the different periods of digital elevation models (DEMs). A physical-based model, the Integrated Hydrology Model (InHM), is used to simulate the hydrologic response before and after the landslide, respectively. The influence of the underlying surface conditions is then discussed based on the output data, such as the hydrograph, distributed water depth and local runoff. The study leads to the following generalized conclusions: 1) the impact of the landslides on hydrologic response does exist, and the greater the proportion of surface flow in the total runoff is, the greater the impact will be; 2) the peak flow from the outlet increased after the landslide, but the shape of the hydrograph has little change; 3) the effect of the landslides on the local runoff is relatively obvious, and this elevates the local flash floods risk; 4) the difference of hydrologic responses between the two periods (before and after the landslide occurring) becomes larger with the increasing rainfall, with a threshold of rapid growth at the rainfall frequencies of once in every 50 years, but there is a limit. The improved understanding of the impact of landslides on the hydrologic response in Jianpinggou catchment provides valuable theoretical support for the storm flood forecast.

Estrogenic activity, estrogens, and calcium in runoff post-layer litter application from rainfall simulated events

USDA-ARS?s Scientific Manuscript database

Estrogens in runoff from fields fertilized with animal wastes have been implicated as endocrine disruptors of fish in recipient surface waters. The goal of this study was to measure estrogenic activity in runoff post-application of animal waste with the greatest potential for estrogenic activity - ...

How much complexity is warranted in a rainfall-runoff model?

Treesearch

A.J. Jakeman; G.M. Hornberger

1993-01-01

Development of mathmatical models relating the precipitation incident upon a catchment to the streamflow emanating from the catchment has been a major focus af surface water hydrology for decades. Generally, values for parameters in such models must be selected so that runoff calculated from the model "matches" recorded runoff from some historical period....

High spatial-temporal resolution and integrated surface and subsurface precipitation-runoff modelling for a small stormwater catchment

NASA Astrophysics Data System (ADS)

Hailegeorgis, Teklu T.; Alfredsen, Knut

2018-02-01

Reliable runoff estimation is important for design of water infrastructure and flood risk management in urban catchments. We developed a spatially distributed Precipitation-Runoff (P-R) model that explicitly represents the land cover information, performs integrated modelling of surface and subsurface components of the urban precipitation water cycle and flow routing. We conducted parameter calibration and validation for a small (21.255 ha) stormwater catchment in Trondheim City during Summer-Autumn events and season, and snow-influenced Winter-Spring seasons at high spatial and temporal resolutions of respectively 5 m × 5 m grid size and 2 min. The calibration resulted in good performance measures (Nash-Sutcliffe efficiency, NSE = 0.65-0.94) and acceptable validation NSE for the seasonal and snow-influenced periods. The infiltration excess surface runoff dominates the peak flows while the contribution of subsurface flow to the sewer pipes also augments the peak flows. Based on the total volumes of simulated flow in sewer pipes (Qsim) and precipitation (P) during the calibration periods, the Qsim/P ranges from 21.44% for an event to 56.50% for the Winter-Spring season, which are in close agreement with the observed volumes (Qobs/P). The lowest percentage of precipitation volume that is transformed to the total simulated runoff in the catchment (QT) is 79.77%. Computation of evapotranspiration (ET) indicated that the ET/P is less than 3% for the events and snow-influenced seasons while it is about 18% for the Summer-Autumn season. The subsurface flow contribution to the sewer pipes are markedly higher than the total surface runoff volume for some events and the Summer-Autumn season. The peakiest flow rates correspond to the Winter-Spring season. Therefore, urban runoff simulation for design and management purposes should include two-way interactions between the subsurface runoff and flow in sewer pipes, and snow-influenced seasons. The developed urban P-R model is useful for better computation of runoff generated from different land cover, for assessments of stormwater management techniques (e.g. the Low Impact Development or LID) and the impacts of land cover and climate change. There are some simplifications or limitations such as the runoff routing does not involve detailed sewer hydraulics, effects of leakages from water supply systems and faulty/illegal connections from sanitary sewer are not considered, the model cannot identify actual locations of the interactions between the subsurface runoff and sewer pipes and lacks parsimony.

Modeling Episodic Surface Runoff in an Arid Environment

NASA Astrophysics Data System (ADS)

Waichler, S. R.; Wigmosta, M. S.

2003-12-01

Methods were developed for estimating episodic surface runoff in arid eastern Washington, USA. Small (1--10 km2) catchments in this region with mean annual precipitation around 180 mm produce runoff in about half the years, and such events usually occur during winter when a widespread cold snap and possible snow accumulation is followed by warmer temperatures and rainfall. Existence of frozen soil appears to be a key factor, and a moving average of air temperature is an effective predictor of soil temperature. The watershed model DHSVM simulates snow accumulation and ablation reasonably well at a monitoring location, but the same model applied in distributed mode across a 850 km2 basin overpredicts runoff. Inadequate definition of local meteorology appears to limit the accuracy of runoff predictions. However, runoff estimates of sufficient quality to support modeling of long-term groundwater recharge and sediment transport may be found in focusing on recurrence intervals and volumes rather than hydrographs. Usefulness of upland watershed modeling to environmental management of the Hanford Site and an adjacent military reservation will likely improve through sensitivity analysis of basic assumptions about upland water balance.

Methodology to improve process understanding of surface runoff causing damages to buildings by analyzing insurance data records

NASA Astrophysics Data System (ADS)

Bernet, Daniel; Prasuhn, Volker; Weingartner, Rolf

2015-04-01

Several case studies in Switzerland highlight that many buildings which are damaged by floods are not located within the inundation zones of rivers, but outside the river network. In urban areas, such flooding can be caused by drainage system surcharge, low infiltration capacity of the urbanized landscape etc. However, in rural and peri-urban areas inundations are more likely caused by surface runoff formed on natural and arable land. Such flash floods have very short response time, occur rather diffusely and, thus, are very difficult to observe directly. In our approach, we use data records from private, but mostly from public insurance companies. The latter, present in 19 out of the total 26 Cantons of Switzerland, insure (almost) every building within the respective administrative zones and, in addition, hold a monopoly position. Damage claims, including flood damages, are usually recorded and, thus, data records from such public insurance companies are a very profitable data source to better understand surface runoff leading to damages. Although practitioners agree that this process is relevant, there seems to be a knowledge gap concerning spatial and temporal distributions as well as triggers and influencing factors of such damage events. Within the framework of a research project, we want to address this research gap and improve the understanding of the process chain from surface runoff formation up to possible damages to buildings. This poster introduces the methodology, which will be applied to a dataset including data from the majority of all 19 public insurance companies for buildings in Switzerland, counting over 50'000 damage claims, in order to better understand surface runoff. The goal is to infer spatial and temporal patterns as well as drivers and influencing factors of surface runoff possibly causing damages. In particular, the workflow of data acquisition, harmonization and treatment is outlined. Furthermore associated problems and challenges are discussed. Ultimately, the improved process understanding will be used to develop a new modeling approach.

Experimental study of water fluxes in a residential area: 2. Road infiltration, runoff and evaporation

NASA Astrophysics Data System (ADS)

Ragab, R.; Rosier, P.; Dixon, A.; Bromley, J.; Cooper, J. D.

2003-08-01

Lack of accurate data has led some hydrologists and city planners to assume that urban infiltration is zero and runoff is 100% of the rainfall. These assumptions lead to an over estimation of road runoff volume and an underestimation of direct recharge to groundwater, which is already rising under some UK cities. This study investigates infiltration and runoff processes and quantifies the percentage of rainfall that contributes to storm drainage, and that which infiltrates through different types of road surface. Access tubes were installed for measuring soil water content using a neutron probe in three car parks, a road and a grass site at the Centre for Ecology and Hydrology, Crowmarsh Gifford, Wallingford. Storm drainage was recorded at the exit of the Thamesmead Estate in Crowmarsh Gifford, just before the drain joins the River Thames at Wallingford. Rainfall and water table depth were also recorded. Weekly measurements of soil moisture content indicated that the top 40 cm layer is not influenced by water-table fluctuations and, therefore, positive changes in soil moisture could be attributed to infiltration of rainfall through the surface. Depending on the nature of the surface, subsurface layers, level of traffic, etc., between 6 and 9% of rainfall was found to infiltrate through the road surfaces studied. The storm drainage generated by road runoff revealed a flow pattern similar to that of the receiving watercourse (River Thames) and increased with the increase of infiltration and soil water content below the road surface. The ratio of runoff to rainfall was 0·7, 0·9 and 0·5 for annual, winter (October-March) and summer (April-September) respectively. As the results of the infiltration indicated that 6 to 9% of annual rainfall infiltrates through the road surface, this means that evaporation represents, 21-24% of annual rainfall, with more evaporation taking place during summer than winter.

Concentrations of polycyclic aromatic hydrocarbons (PAHs) and azaarenes in runoff from coal-tar- and asphalt-sealcoated pavement.

PubMed

Mahler, Barbara J; Van Metre, Peter C; Foreman, William T

2014-05-01

Coal-tar-based sealcoat, used extensively on parking lots and driveways in North America, is a potent source of PAHs. We investigated how concentrations and assemblages of PAHs and azaarenes in runoff from pavement newly sealed with coal-tar-based (CT) or asphalt-based (AS) sealcoat changed over time. Samples of simulated runoff were collected from pavement 5 h to 111 d following application of AS or CT sealcoat. Concentrations of the sum of 16 PAHs (median concentrations of 328 and 35 μg/L for CT and AS runoff, respectively) in runoff varied relatively little, but rapid decreases in concentrations of azaarenes and low molecular weight PAHs were offset by increases in high molecular weight PAHs. The results demonstrate that runoff from CT-sealcoated pavement, in particular, continues to contain elevated concentrations of PAHs long after a 24-h curing time, with implications for the fate, transport, and ecotoxicological effects of contaminants in runoff from CT-sealcoated pavement. Published by Elsevier Ltd.

Application of GIS in Modeling Zilberchai Basin Runoff

NASA Astrophysics Data System (ADS)

Malekani, L.; Khaleghi, S.; Mahmoodi, M.

2014-10-01

Runoff is one of most important hydrological variables that are used in many civil works, planning for optimal use of reservoirs, organizing rivers and warning flood. The runoff curve number (CN) is a key factor in determining runoff in the SCS (Soil Conservation Service) based hydrologic modeling method. The traditional SCS-CN method for calculating the composite curve number consumes a major portion of the hydrologic modeling time. Therefore, geographic information systems (GIS) are now being used in combination with the SCS-CN method. This work uses a methodology of determining surface runoff by Geographic Information System model and applying SCS-CN method that needs the necessary parameters such as land use map, hydrologic soil groups, rainfall data, DEM, physiographic characteristic of the basin. The model is built by implementing some well known hydrologic methods in GIS like as ArcHydro, ArcCN-Runoff for modeling of Zilberchai basin runoff. The results show that the high average weighted of curve number indicate that permeability of the basin is low and therefore likelihood of flooding is high. So the fundamental works is essential in order to increase water infiltration in Zilberchai basin and to avoid wasting surface water resources. Also comparing the results of the computed and observed runoff value show that use of GIS tools in addition to accelerate the calculation of the runoff also increase the accuracy of the results. This paper clearly demonstrates that the integration of GIS with the SCS-CN method provides a powerful tool for estimating runoff volumes in large basins.

Hybrid wavelet-support vector machine approach for modelling rainfall-runoff process.

PubMed

Komasi, Mehdi; Sharghi, Soroush

2016-01-01

Because of the importance of water resources management, the need for accurate modeling of the rainfall-runoff process has rapidly grown in the past decades. Recently, the support vector machine (SVM) approach has been used by hydrologists for rainfall-runoff modeling and the other fields of hydrology. Similar to the other artificial intelligence models, such as artificial neural network (ANN) and adaptive neural fuzzy inference system, the SVM model is based on the autoregressive properties. In this paper, the wavelet analysis was linked to the SVM model concept for modeling the rainfall-runoff process of Aghchai and Eel River watersheds. In this way, the main time series of two variables, rainfall and runoff, were decomposed to multiple frequent time series by wavelet theory; then, these time series were imposed as input data on the SVM model in order to predict the runoff discharge one day ahead. The obtained results show that the wavelet SVM model can predict both short- and long-term runoff discharges by considering the seasonality effects. Also, the proposed hybrid model is relatively more appropriate than classical autoregressive ones such as ANN and SVM because it uses the multi-scale time series of rainfall and runoff data in the modeling process.

Modelling of catchment nitrogen concentrations response to observed varying fertilizer application intensities

NASA Astrophysics Data System (ADS)

Jomaa, Seifeddine; Jiang, Sanyuan; Yang, Xiaoqiang; Rode, Michael

2016-04-01

Eutrophication is a serious environmental problem. Despite numerous experimental and modelling efforts, understanding of the effect of land use and agriculture practices on in-stream nitrogen fluxes is still not fully achieved. This study combined intensive field monitoring and numerical modelling using 30 years of surface water quality data of a drinking water reservoir catchment in central Germany. The Weida catchment (99.5 km2) is part of the Elbe river basin and has a share of 67% of agricultural land use with significant changes in agricultural practices within the investigation period. The geology of the Weida catchment is characterized by clay schists and eruptive rocks, where rocks have low permeability. The semi-distributed hydrological water quality HYPE (Hydrological Predictions for the Environment) model was used to reproduce the measured data. First, the model was calibrated for discharge and nitrate-N concentrations (NO3-N) during the period 1997-2000. Then, the HYPE model was validated successfully for three different periods 1983-1987, 1989-1996 and 2000-2003, which are charaterized by different fertilizer application rates (with lowest discharge prediction performance of NSE = 0.78 and PBIAS = 3.74%, considering calibration and validation periods). Results showed that the measured as well as simulated in-stream nitrate-N concentration respond quickly to fertilizer application changes (increase/decrease). This rapid response can be explained with short residence times of interflow and baseflow runoff components due to the hardrock geological properties of the catchment. Results revealed that the surface runoff and interflow are the most dominant runoff components. HYPE model could reproduce reasonably well the NO3-N daily loads for varying fertilizer application, when detailed input data in terms of crop management (field-specific survey) are considered.

Distributions of typical contaminant species in urban short-term storm runoff and their fates during rain events: a case of Xiamen City.

PubMed

Wei, Qunshan; Zhu, Gefu; Wu, Peng; Cui, Li; Zhang, Kaisong; Zhou, Jingjing; Zhang, Wenru

2010-01-01

The pollutants in urban storm runoff, which lead to an non-point source contamination of water environment around cities, are of great concerns. The distributions of typical contaminants and the variations of their species in short term storm runoff from different land surfaces in Xiamen City were investigated. The concentrations of various contaminants, including organic matter, nutrients (i.e., N and P) and heavy metals, were significantly higher in parking lot and road runoff than those in roof and lawn runoff. The early runoff samples from traffic road and parking lot contained much high total nitrogen (TN 6-19 mg/L) and total phosphorus (TP 1-3 mg/L). A large proportion (around 60%) of TN existed as total dissolved nitrogen (TDN) species in most runoff. The percentage of TDN and the percentage of total dissolved phosphorus remained relatively stable during the rain events and did not decrease as dramatically as TN and TP. In addition, only parking lot and road runoff were contaminated by heavy metals, and both Pb (25-120 microg/L) and Zn (0.1-1.2 mg/L) were major heavy metals contaminating both runoff. Soluble Pb and Zn were predominantly existed as labile complex species (50%-99%), which may be adsorbed onto the surfaces of suspended particles and could be easily released out when pH decreased. This would have the great impact to the environment.

Surface roughness and runoff

NASA Astrophysics Data System (ADS)

Szabó, Judit Alexandra; Szabó, Boglárka; Centeri, Csaba; Józsa, Sándor; Szalai, Zoltán; Jakab, Gergely

2017-04-01

Soil surface conditions changes dynamically during a precipitation event. The changes involve compaction, aggregate detachment and of course transportation by runoff or drop erosion. Those processes together have an effect on the transport process of the soil particles and aggregates, and influences the roughness of the soil surface as well. How does surface roughness have an effect on the aggregate and particle size distribution of the sediment? How does the sediment connectivity change from precipitation event to precipitation event? Beside the previous questions on of the main aim of the present research is to apply rainfall simulators for the built-up of a complex approach, rather than to concentrate only on one of two factors. Hence four types of sample were collected during the simulation experiment sequences: 1) photos were taken about the surface before and after the rain, in order to build digital surface models; 2) all the runoff and eroded sediment was collected; 3) soil loss due to drop erosion was also sampled separately; and 4) undisturbed crust samples were collected for thin section analyses. Though the runoff ratio was smaller than what, the preliminary results suggest that the sediment connectivity covered bigger area on crusty surface, than on a rough one. These ambiguous data may be connected to the soil crust development. J. A. Szabó wish to acknowledge the support of NTP-NFTÖ-16-0203. G. Jakab wish to acknowledge the support of János Bolyai Fellowship.

The power of runoff

NASA Astrophysics Data System (ADS)

Wörman, A.; Lindström, G.; Riml, J.

2017-05-01

Although the potential energy of surface water is a small part of Earth's energy budget, this highly variable physical property is a key component in the terrestrial hydrologic cycle empowering geomorphological and hydrological processes throughout the hydrosphere. By downscaling of the daily hydrometeorological data acquired in Sweden over the last half-century this study quantifies the spatial and temporal distribution of the dominating energy components in terrestrial hydrology, including the frictional resistance in surface water and groundwater as well as hydropower. The energy consumed in groundwater circulation was found to be 34.6 TWh/y or a heat production of approximately 13% of the geothermal heat flux. Significant climate driven, periodic fluctuations in the power of runoff, stream flows and groundwater circulation were revealed that have not previously been documented. We found that the runoff power ranged from 173 to 260 TWh/y even when averaged over the entire surface of Sweden in a five-year moving window. We separated short-term fluctuations in runoff due to precipitation filtered through the watershed from longer-term seasonal and climate driven modes. Strong climate driven correlations between the power of runoff and climate indices, wind and solar intensity were found over periods of 3.6 and 8 years. The high covariance that we found between the potential energy of surface water and wind energy implies significant challenges for the combination of these renewable energy sources.

Long-term effects of drinking-water treatment residuals on dissolved phosphorus export from vegetated buffer strips.

PubMed

Habibiandehkordi, Reza; Quinton, John N; Surridge, Ben W J

2015-04-01

The export of dissolved phosphorus (P) in surface runoff from agricultural land can lead to water quality degradation. Surface application of aluminium (Al)-based water treatment residuals (Al-WTRs) to vegetated buffer strip (VBS) soils can enhance P removal from surface runoff during single runoff events. However, the longer-term effects on P removal in VBSs following application of products such as Al-WTR remain uncertain. We used field experimental plots to examine the long-term effects of applying a freshly generated Al-WTR to VBSs on dissolved P export during multiple runoff events, occurring between 1 day and 42 weeks after the application of Al-WTR. Vegetated buffer strip plots amended with Al-WTR significantly reduced soluble reactive P and total dissolved P concentrations in surface runoff compared to both unamended VBS plots and control plots. However, the effectiveness of Al-WTR decreased over time, by approximately 70% after 42 weeks compared to a day following Al-WTR application. Reduced performance did not appear to be due to drying of Al-WTR in the field. Instead, the development of preferential flow paths as well as burying of Al-WTR with freshly deposited sediments may explain these observations. Better understanding of the processes controlling long-term P removal by Al-WTR is required for effective management of VBSs.

[Research of the Stormwater Runoff and Pollution Characteristics in Rural Area of Yuhang District, Hangzhou].

PubMed

Duan, Sheng-hui; Zhao, Yu; Shan, Bao-qing; Tang, Wen-zhong; Zhang, Wen-qiang; Zhang, Shu-zhen; Lang, Chao

2015-10-01

In order to investigate the pollution characteristics of stormwater runoff in the southern developed rural region, the runoff samples were collected from four different underlying surfaces during three storm events in Caoqiao and Pujia Tou, which are two typical villages and are located in Yuhang District of Hangzhou. The content of nutrition (nitrogen and phosphorus) and heavy metals (Mn, Cu, Zn, Ni, Cr, Cd, As, Pb) in the simples were analyzed, and the difference of EMC ( event mean concentration) and pollution load of the contaminants in the runoff on different underlying surfaces were compared. The results showed that the EMC of TSS, COD, NH4(+)-N, TP and TN were 16.19, 21.01, 0.74, 1.39 and 2.39 mg x L(-1) in the Caoqiao, respectively; as to Pujia Tou, they were 3.10, 15.69, 0.90, 0.78 and 3.58 mg x L(-1), respectively. The content of heavy metals was all lower than the national surface water quality of two type water in the runoff. Compared with the quality standards for surface water, the EMC of TP was 9 times and 3. 5 times higher and TN was 1. 8 times and 1. 2 times higher in two areas. Besides, the pollution loads of TSS and COD were the highest in farmland.

Verification of Rapid Focused-Recharge in Depressions of Kuwait and the Arabian Peninsula Using Thermal and VNIR Remote Sensing

NASA Astrophysics Data System (ADS)

Rotz, R. R.; Milewski, A.

2013-12-01

In the Arabian Peninsula, freshwater recharge from rainfall is infrequent. Recharge is typically focused in small depressions that fill with seasonal runoff and potentially form freshwater lenses. This phenomenon has been verified in the Raudhatain watershed in Kuwait. This study aims to substantiate previously hypothesized lens locations and detect water in the subsurface by using thermal remote sensing and rainfall data. Potential freshwater lenses (~142) have been previously postulated throughout Kuwait and Saudi Arabia, but lack verification due to inadequate monitoring networks. We hypothesize that due to water's unique heat capacity, recharge zones can be detected by identifying areas with lower changes in surface radiance values than neighboring dry areas between day and night after peak or sustained rainfall. If successful, recharge zones and freshwater lenses can be identified and verified in remote hyper-arid regions. We collected 320 high-resolution (15m - 90m), low cloud cover (<10%) images in the visible near-infrared (VNIR) and thermal infrared (TIR) wavelengths obtained from the Advanced Spaceborne Thermal Emission and Reflection Radiometer sensor (ASTER) between 2004 and 2012. Overlapping day and night images were subtracted from each other to show surface radiance fluctuations and difference images were compared with rainfall data from Daily TRMM_3B42v7a between 2004 and 2012. Several lens locations, runoff channels, agricultural regions, and wetlands were detected in areas where radiance values change between 0.067 - 2.25 Wsr-1m-2 from day to night scenes and verified by Google Earth (15m), Landsat (30m), and ASTER VNIR (15m) images. Additionally, two seasonal peak rainfall (~35mm/day) events positively correlate with the surface radiance difference values. Surface radiance values for dry areas adjacent to the postulated lens locations range between 2.25 - 12.2 Wsr-1m-2. Results demonstrate the potential for shallow groundwater detection through the presence of ephemeral water bodies in hyper-arid regions en masse; however, the absence of comparable diurnal images limits data in these regions. Linking high rainfall events with low diurnal surface radiance images is ideal for capturing the presence of temporary surface runoff and recharge zones. Expanded research on hyper-arid regions including thermal values, proposed lens locations, and in-situ data will provide more data points and bolster the methodology.

Estimation of Shallow Groundwater Discharge and Nutrient Load into a River

Treesearch

Ying Ouyang

2012-01-01

Pollution of rivers with excess nutrients due to groundwater discharge, storm water runoff, surface loading,and atmospheric deposition is an increasing environmental concern worldwide. While the storm water runoff and surface loading of nutrients into many rivers have been explored in great detailed, the groundwater discharge of nutrients into the rivers has not yet...

Evaluation of nitrogen and phosphorus transport with runoff from fairway turf managed with hollow tine core cultivation and verticutting

USDA-ARS?s Scientific Manuscript database

Enrichment of surface waters with excess nutrients is associated with increased algal blooms, euthrophication and hypoxic zones, as reported in the northern Gulf of Mexico. A source of nutrients to surface waters results from fertilizer runoff. Management strategies used to maintain turf on golf cou...

Water quality of surface runoff and lint yield in cotton under furrow irrigation in Northeast Arkansas

USDA-ARS?s Scientific Manuscript database

Use of furrow irrigation in row crop production is a common practice through much of the Midsouth US and yet, nutrients can be transported off-site through surface runoff. A field study with cotton (Gossypium hirsutum, L.) was conducted to understand the impact of furrow tillage practices and nitrog...

Modeling diffuse sources of surface water contamination with plant protection products

NASA Astrophysics Data System (ADS)

Wendland, Sandra; Bock, Michael; Böhner, Jürgen; Lembrich, David

2015-04-01

Entries of chemical pollutants in surface waters are a serious environmental problem. Among water pollutants plant protection products (ppp) from farming practice are of major concern not only for water suppliers and environmental agencies, but also for farmers and industrial manufacturers. Lost chemicals no longer fulfill their original purpose on the field, but lead to severe damage of the environment and surface waters. Besides point-source inputs of chemical pollutants, the diffuse-source inputs from agricultural procedures play an important and not yet sufficiently studied role concerning water quality. The two most important factors for diffuse inputs are erosion and runoff. The latter usually occurs before erosion begins, and is thus often not visible in hindsight. Only if it has come to erosion, it is obvious to expect runoff in foresight at this area, too. In addition to numerous erosion models, there are also few applications to model runoff processes available. However, these conventional models utilize approximations of catchment parameters based on long-term average values or theoretically calculated concentration peaks which can only provide indications to relative amounts. Our study aims to develop and validate a simplified spatially-explicit dynamic model with high spatiotemporal resolution that enables to measure current and forecast runoff potential not only at catchment scale but field-differentiated. This method allows very precise estimations of runoff risks and supports risk reduction measures to be targeted before fields are treated. By focusing on water pathways occurring on arable land, targeted risk reduction measures like buffer strips at certain points and adapted ppp use can be taken early and pollution of rivers and other surface waters through transported pesticides, fertilizers and their products could be nearly avoided or largely minimized. Using a SAGA-based physical-parametric modeling approach, major factors influencing runoff (relief, soil properties, weather conditions and crop coverage) are represented. Water balance parameters are modeled in daily steps, taking into account relief determined discharge pathways, runoff velocity and number of field boundaries passed until receiving streams are reached. Model development is based on a comprehensive monitoring campaign at 3 smaller catchments in North Rhine-Westphalia (Germany), equipped with two gauges each, upstream and downstream, an optical Trios probe and four Isco-Samplers. The temporal high resolution monitoring of discharge, ppp, orthophosphate and nitrate-nitrogen enables an evaluation of runoff simulations in relation with rain events. First model results suggest that the simulation of surface runoff pathways enables a spatial-explicit identification of fields contributing to pollutant inputs. We assume that targeted actions on few fields will help solving the problem of diffuse inputs of ppp in our surface water to a considerable extent.

The application of electrical conductivity as a tracer for hydrograph separation in urban catchments

USGS Publications Warehouse

Pellerin, B.A.; Wollheim, W.M.; Feng, X.; Vororsmarty, C.J.

2008-01-01

Two-component hydrograph separation was performed on 19 low-to-moderate intensity rainfall events in a 4.1-km2 urban watershed to infer the relative and absolute contribution of surface runoff (e.g. new water) to stormflow generation between 2001 and 2003. The electrical conductivity (EC) of water was used as a continuous and inexpensive tracer, with order of magnitude differences in precipitation (12-46 ??S/cm) and pre-event streamwater EC values (520-1297 ??S/cm). While new water accounted for most of the increased discharge during storms (61-117%), the contribution of new water to total discharge during events was typically lower (18-78%) and negatively correlated with antecedent stream discharge (r2 = 0??55, p < 0??01). The amount of new water was positively correlated with total rainfall (r2 = 0??77), but hydrograph separation results suggest that less than half (9-46%) of the total rainfall on impervious surfaces is rapidly routed to the stream channel as new water. Comparison of hydrograph separation results using non-conservative tracers (EC and Si) and a conservative isotopic tracer (??D) for two events showed similar results and highlighted the potential application of EC as an inexpensive, high frequency tracer for hydrograph separation studies in urban catchments. The use of a simple tracer-based approach may help hydrologists and watershed managers to better understand impervious surface runoff, stormflow generation and non-point-source pollutant loading to urban streams. Copyright ?? 2007 John Wiley & Sons, Ltd.

Scaling considerations related to interactions of hydrologic, pedologic and geomorphic processes (Invited)

NASA Astrophysics Data System (ADS)

Sidle, R. C.

2013-12-01

Hydrologic, pedologic, and geomorphic processes are strongly interrelated and affected by scale. These interactions exert important controls on runoff generation, preferential flow, contaminant transport, surface erosion, and mass wasting. Measurement of hydraulic conductivity (K) and infiltration capacity at small scales generally underestimates these values for application at larger field, hillslope, or catchment scales. Both vertical and slope-parallel saturated flow and related contaminant transport are often influenced by interconnected networks of preferential flow paths, which are not captured in K measurements derived from soil cores. Using such K values in models may underestimate water and contaminant fluxes and runoff peaks. As shown in small-scale runoff plot studies, infiltration rates are typically lower than integrated infiltration across a hillslope or in headwater catchments. The resultant greater infiltration-excess overland flow in small plots compared to larger landscapes is attributed to the lack of preferential flow continuity; plot border effects; greater homogeneity of rainfall inputs, topography and soil physical properties; and magnified effects of hydrophobicity in small plots. At the hillslope scale, isolated areas with high infiltration capacity can greatly reduce surface runoff and surface erosion at the hillslope scale. These hydropedologic and hydrogeomorphic processes are also relevant to both occurrence and timing of landslides. The focus of many landslide studies has typically been either on small-scale vadose zone process and how these affect soil mechanical properties or on larger scale, more descriptive geomorphic studies. One of the issues in translating laboratory-based investigations on geotechnical behavior of soils to field scales where landslides occur is the characterization of large-scale hydrological processes and flow paths that occur in heterogeneous and anisotropic porous media. These processes are not only affected by the spatial distribution of soil physical properties and bioturbations, but also by geomorphic attributes. Interactions among preferential flow paths can induce rapid pore water pressure response within soil mantles and trigger landslides during storm peaks. Alternatively, in poorly developed and unstructured soils, infiltration occurs mainly through the soil matrix and a lag time exists between the rainfall peak and development of pore water pressures at depth. Deep, slow-moving mass failures are also strongly controlled by secondary porosity within the regolith with the timing of activation linked to recharge dynamics. As such, understanding both small and larger scale processes is needed to estimate geomorphic impacts, as well as streamflow generation and contaminant migration.

STWIR, a microorganism transport with infiltration and runoff add-on module for the KINEROS2 runoff and erosion model: documentation and user manual

USDA-ARS?s Scientific Manuscript database

Runoff from manured fields is often considered to be the source of microorganisms in the surface water used for irrigation, recreation, and household needs. Concerns about microbial safety of this water resulted in development of predictive models for estimating the concentrations and total numbers ...

Predicting forest road surface erosion and storm runoff from high-elevation sites

Treesearch

J. M. Grace III

2017-01-01

Forest roads are a concern in management because they represent areas of elevated risks associated with soil erosion and storm runoff connectivity to stream systems. Storm runoff emanating from forest roads and their connectivity to downslope resources can be influenced by a myriad of factors, including storm characteristics, management practices, and the interaction...

Modeling climate change effects on runoff and soil erosion in southeastern Arizona rangelands and implications for mitigation with rangeland conservation practices

USDA-ARS?s Scientific Manuscript database

Climate change is expected to impact runoff and soil erosion on rangelands in the southwestern United States. This study was done to evaluate the potential impacts of precipitation changes on soil erosion and surface runoff in southeastern Arizona using seven GCM models with three emission scenarios...

Rainfall simulations to study the types of groundcover on surface runoff and soil erosion in Champagne vineyards in France

NASA Astrophysics Data System (ADS)

Xavier, Morvan; Christophe, Naisse; Issa Oumarou, Malam; Jean-François, Desprats; Anne, Combaud; Olivier, Cerdan

2015-04-01

In the literature, grass cover is often considered to be one of the best methods of limiting runoff in the vineyards; But results can vary, especially when the plot area is <2 m². However, in any study to our knowledge, the way grass cover is structured in the inter-row is taken into account to explain the variability of runoff and soil loss. The objective of this study, conducted in Champagne vineyards in France, was to quantify the influence of the cultivation practices in the inter-rows of vines and determine the influence of the density of the grass cover in the wheel tracks on the surface runoff and soil erosion in experimental plots of 0.25 m2 under simulated rainfall. Three types of ground cover were studied. In the bark-and-vine-prunings plots, the runoff coefficient ranged from 1.3 to 4.0% and soil losses were <1 g/m²/h. In the bare soil plot, the highest runoff coefficient of the study was found (80.0%) and soil losses reached 7.4 g/m²/h. In the grass cover plots, the runoff coefficient and amount of eroded soil were highly variable: the runoff coefficients ranged from 0.4 to 77.0%, and soil losses were between less than 1 and 13.4 g/m²/h. Soil type, soil moisture, slope and agricultural practices did not account for the variability. In fact, the density of grass cover in the wheel tracks explained a portion of this variability. The lack of grass in the centre of the inter-row allowed for a preferential flow and created an erosion line in the wheel tracks where the soil was compacted. This study showed that grass cover in a vineyard was not necessarily sufficient to reduce surface runoff and prevent soil erosion. To be effective, the grass cover must be dense enough in the wheel tracks of agricultural machinery to avoid runoff coefficients close to those achieved with bare soil.

Increasing runoff and sediment load from the Greenland ice sheet at kangerlussuaq (Sonder Stromfjord) in a 30-year perspective, 1979-2008

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mernild, Sebastian Haugard; Liston, Glen; Hasholt, Bent

2009-01-01

This observation and modeling study provides insights into runoff and sediment load exiting the Watson River drainage basin, Kangerlussuaq, West Greenland during a 30 year period (1978/79-2007/08) when the climate experienced increasing temperatures and precipitation. The 30-year simulations quantify the terrestrial freshwater and sediment output from part of the Greenland Ice Sheet (GrIS) and the land between the GrIS and the ocean, in the context of global warming and increasing GrIS surface melt. We used a snow-evolution modeling system (SnowModel) to simulate the winter accumulation and summer ablation processes, including runoff and surface mass balance (SMB), of the Greenland icemore » sheet. Observed sediment concentrations were related to observed runoff, producing a sediment-load time series. To a large extent, the SMB fluctuations could be explained by changes in net precipitation (precipitation minus evaporation and sublimation), with 8 out of 30 years having negative SMB, mainly because of relatively low annual net precipitation. The overall trend in net precipitation and runoff increased significantly, while 5MB increased insignificantly throughout the simulation period, leading to enhanced precipitation of 0.59 km{sup 3} w.eq. (or 60%), runoff of 0.43 km{sup 3} w.eq (or 54%), and SMB of 0.16 km3 w.eq. (or 86%). Runoff rose on average from 0.80 km{sup 3} w.eq. in 1978/79 to 1.23 km{sup 3} w.eq. in 2007/08. The percentage of catchment oudet runoff explained by runoff from the GrIS decreased on average {approx} 10%, indicating that catchment runoff throughout the simulation period was influenced more by precipitation and snowmelt events, and less by runoff from the GrIS. Average variations in the increasing Kangerlussuaq runoff from 1978/79 through 2007/08 seem to follow the overall variations in satellite-derived GrIS surface melt, where 64% of the variations in simulated runoff were explained by regional melt conditions on the GrIS. Throughout the simulation period, the sediment load varied from a minimum of 0.96 x 10{sup 6} t y{sup -1} in 1991/92 to a maximum of 3.52 x 10{sup 6} t y{sup -1} in 2006/07, showing an average increase of sediment load of 9.42 x 10{sup 5} t (or 72%) throughout the period.« less

Ice sheet runoff and Dansgaard-Oeschger Cycles

NASA Astrophysics Data System (ADS)

Hewitt, Ian; Wolff, Eric; Fowler, Andrew; Clark, Chris; Evatt, Geoff; Johnson, Helen; Munday, David; Rickaby, Ros; Stokes, Chris

2016-04-01

Many northern hemisphere climate records, particularly those from around the North Atlantic, show a series of rapid climate changes that recurred on centennial to millennial timescales throughout most of the last glacial period. These Dansgaard-Oeschger (D-O) sequences are observed most prominently in Greenland ice cores, although they have a global signature, including an out of phase Antarctic signal. They consist of warming jumps of order 10°C, occurring in typically 40 years, followed generally by a slow cooling (Greenland Interstadial, GI) lasting between a few centuries and a few millennia, and then a final rapid temperature drop into a cold Greenland Stadial (GS) that lasts for a similar period. Most explanations for D-O events call on changes in Atlantic meridional overturning circulation strength, and the majority of such explanations use changes in freshwater delivery from ice sheets as a trigger. Many have relied on large inputs of freshwater from singular events (such as lake outbursts or iceberg armadas) to push the AMOC into its cold state. However the evidence for such events at the right time in each cycle is sparse. Here we investigate mechanisms that would arise from a change in the rate of ice sheet runoff, which would be a natural feedback from each rapid warming or cooling event. Recent work has suggested that AMOC is most easily disrupted by freshwater delivered through the Arctic. We investigate whether the proposed AMOC changes could have occurred as part of a natural oscillation, in which runoff from the Laurentide ice sheet into the Arctic is controlled by temperature around the North Atlantic. The Arctic buffers the salinity changes, but under warm conditions, high runoff eventually leads to water entering the North Atlantic with low enough salinity to switch AMOC into its weaker state. Under the colder conditions now prevailing, the Arctic is starved of runoff, and the salinity rises until a further switch occurs. Contrary to many previous studies, this mechanism does not require large freshwater pulses to the North Atlantic. Instead, steady changes in ice-sheet runoff, driven by the AMOC, lead to a naturally arising oscillator, in which the rapid warmings come about because the Arctic Ocean is starved of freshwater. The changing size of the ice sheets would have affected the magnitude and extent of runoff, and we suggest that this could provide a simple explanation for the absence of the events during interglacials and around the time of glacial maxima. We construct a simple model to investigate whether the timescales and magnitudes would in practice make this a viable mechanism, and we consider other roles that runoff could play. Heinrich events, delivering additional freshwater into the Atlantic during a Greenland stadial, play no direct role in this mechanism, but would serve to delay the switch to faster AMOC.

The effect of different surface materials on runoff quality in permeable pavement systems.

PubMed

Li, Haiyan; Li, Zhifei; Zhang, Xiaoran; Li, Zhuorong; Liu, Dongqing; Li, Tanghu; Zhang, Ziyang

2017-09-01

To investigate the effect of different permeable pavement surface materials on the removal of pollutants from urban storm-runoff, six commonly surface materials (porous asphalt, porous concrete, cement brick, ceramic brick, sand base brick, and shale brick) were selected in this study and the research was carried out by column experiments. Except the concentrations of total suspended solids (TSS), chemical oxygen demand (COD), ammonia nitrogen (NH 4 -N), nitrate nitrogen (NO 3 -N), total nitrogen (TN), and total phosphorus (TP) in the influent and effluent that were measured, the removal mechanism of pollutants was discussed further. The results indicate that the surface materials influence the removal efficiency of pollutants greatly and have different effects on certain pollutant. Furthermore, the physical interception and adsorption would be the main mechanism for the removal of pollutants from runoff. For example, for all surface materials, the average removal efficiency of TSS is nearly about 90.0% because of physical interception. Due to the amount of iron oxide, the removal efficiency of COD, NO 3 -N, and TN of shale brick was 88.2, 35.1, and 17.5%, respectively. NH 4 -N and TN can be easily removed by porous asphalt due to the high content of organic matter. By lacking of useful adsorption sites, all the surface materials had little effect on the removal of TP from runoff. This research could offer useful guidelines for the better design of permeable pavement system and promote the insight into the removal mechanism of pollutants in permeable pavement system. Graphical abstract Different types of materials for the different types of pollutants in the runoff purification capacity were significantly different, overall, shale brick and porous asphalt Shale bricks and porous asphalt have a better purification effect according to the six kinds of materials.

Impact of agricultural management on pluvial flash floods - Case study of an extreme event observed in Austria in 2016

NASA Astrophysics Data System (ADS)

Lumassegger, Simon; Achleitner, Stefan; Kohl, Bernhard

2017-04-01

Central Europe was affected by extreme flash floods in summer 2016 triggered by short, high-intensity storm cells. Besides fluvial runoff, local pluvial floods appear to increase recently. In frame of the research project SAFFER-CC (sensitivity assessment of critical condition for local flash floods - evaluating the recurrence under climate change) surface runoff and pluvial flooding is assessed using a coupled hydrological/2D hydrodynamic model for the severely affected municipality of Schwertberg, Upper Austria. In this small catchment several flooding events occurred in the last years, where the most severe event occurred during summer 2016. Several areas could only be reached after the flood wave subsided with observed flood marks up to one meter. The modeled catchment is intensively cultivated with maize, sugar beets, winter wheat and soy on the hillside and hence highly vulnerable to water erosion. The average inclination is relatively steep with 15 % leading to high flow velocities of surface runoff associated with large amounts of transported sediments. To assess the influence of land use and soil conservation on flash floods, field experiments with a portable irrigation spray installation were carried out at different locations. The test plots were subjected to rainfall with constant intensity of 100 mm/h for one hour. Consecutively a super intense, one hour lasting, rainfall hydrograph was applied after 30 minutes at the same plots, ranging from 50 mm/h to 200 mm/h. Surface runoff was collected and measured in a tank and water samples were taken to determine the suspended material load. Large differences of runoff coefficients were determined depending on the agricultural management. The largest discharge was measured in a maize field, where surface runoff occurred immediately after start of irrigation. The determined runoff coefficients ranged from 0.22 for soy up to 0.65 for maize for the same soil type and inclination. The conclusion that runoff is heavily influenced by land use matches well with the observed flow patterns during the storm event in summer 2016. The results clearly indicate the ability to reduce pluvial flash flood impacts by changing agricultural management practices.

Impact of climate change on runoff pollution in urban environments

NASA Astrophysics Data System (ADS)

Coutu, S.; Kramer, S.; Barry, D. A.; Roudier, P.

2012-12-01

Runoff from urban environments is generally contaminated. These contaminants mostly originate from road traffic and building envelopes. Facade envelopes generate lead, zinc and even biocides, which are used for facade protection. Road traffic produces particles from tires and brakes. The transport of these pollutants to the environment is controlled by rainfall. The interval, duration and intensity of rainfall events are important as the dynamics of the pollutants are often modeled with non-linear buildup/washoff functions. Buildup occurs during dry weather when pollution accumulates, and is subsequently washed-off at the time of the following rainfall, contaminating surface runoff. Climate predictions include modified rainfall distributions, with changes in both number and intensity of events, even if the expected annual rainfall varies little. Consequently, pollutant concentrations in urban runoff driven by buildup/washoff processes will be affected by these changes in rainfall distributions. We investigated to what extent modifications in future rainfall distributions will impact the concentrations of pollutants present in urban surface runoff. The study used the example of Lausanne, Switzerland (temperate climate zone). Three emission scenarios (time horizon 2090), multiple combinations of RCM/GCM and modifications in rain event frequency were used to simulate future rainfall distributions with various characteristics. Simulated rainfall events were used as inputs for four pairs of buildup/washoff models, in order to compare future pollution concentrations in surface runoff. In this way, uncertainty in model structure was also investigated. Future concentrations were estimated to be between ±40% of today's concentrations depending on the season and, importantly, on the choice of the RCM/GCM model. Overall, however, the dominant factor was the uncertainty inherent in buildup/washoff models, which dominated over the uncertainty in future rainfall distributions. Consequently, the choice of a proper buildup/washoff model, with calibrated site-specific coefficients, is a major factor in modeling future runoff concentrations from contaminated urban surfaces.

Evaluation of hydrologic components of community land model 4 and bias identification

DOE PAGES

Du, Enhao; Vittorio, Alan Di; Collins, William D.

2015-04-01

Runoff and soil moisture are two key components of the global hydrologic cycle that should be validated at local to global scales in Earth System Models (ESMs) used for climate projection. Here, we have evaluated the runoff and surface soil moisture output by the Community Climate System Model (CCSM) along with 8 other models from the Coupled Model Intercomparison Project (CMIP5) repository using satellite soil moisture observations and stream gauge corrected runoff products. A series of Community Land Model (CLM) runs forced by reanalysis and coupled model outputs was also performed to identify atmospheric drivers of biases and uncertainties inmore » the CCSM. Results indicate that surface soil moisture simulations tend to be positively biased in high latitude areas by most selected CMIP5 models except CCSM, FGOALS, and BCC, which share similar land surface model code. With the exception of GISS, runoff simulations by all selected CMIP5 models were overestimated in mountain ranges and in most of the Arctic region. In general, positive biases in CCSM soil moisture and runoff due to precipitation input error were offset by negative biases induced by temperature input error. Excluding the impact from atmosphere modeling, the global mean of seasonal surface moisture oscillation was out of phase compared to observations in many years during 1985–2004. The CLM also underestimated runoff in the Amazon, central Africa, and south Asia, where soils all have high clay content. We hypothesize that lack of a macropore flow mechanism is partially responsible for this underestimation. However, runoff was overestimated in the areas covered by volcanic ash soils (i.e., Andisols), which might be associated with poor soil porosity representation in CLM. Finally, our results indicate that CCSM predictability of hydrology could be improved by addressing the compensating errors associated with precipitation and temperature and updating the CLM soil representation.« less

Nutrient loss in leachate and surface runoff from surface-broadcast and subsurface-banded broiler litter.

PubMed

Lamba, Jasmeet; Srivastava, Puneet; Way, Thomas R; Sen, Sumit; Wood, C Wesley; Yoo, Kyung H

2013-09-01

Subsurface band application of poultry litter has been shown to reduce the transport of nutrients from fields in surface runoff compared with conventional surface broadcast application. Little research has been conducted to determine the effects of surface broadcast application and subsurface banding of litter on nutrients in leachate. Therefore, a field experiment was conducted to determine the effects of subsurface band application and surface broadcast application of poultry litter on nutrient losses in leachate. Zero-tension pan and passive capillary fiberglass wick lysimeters were installed in situ 50 cm beneath the soil surface of an established tall fescue ( Schreb.) pasture on a sandy loam soil. The treatments were surface broadcast and subsurface-banded poultry litter at 5 Mg ha and an unfertilized control. Results of the rainfall simulations showed that the concentrations of PO-P and total phosphorus (TP) in leachate were reduced by 96 and 37%, respectively, in subsurface-banded litter treatment compared with the surface-applied litter treatment. There was no significant difference in PO-P concentration between control and subsurface-banded litter treatment in leachate. The trend in the loading of nutrients in leachate was similar to the trend in concentration. Concentration and loading of the nutrients (TP, PO-P, NH-N, and NO-N) in runoff from the subsurface-banded treatment were significantly less than for the surface-applied treatment and were similar to those from control plots. These results show that, compared with conventional surface broadcast application of litter, subsurface band application of litter can greatly reduce loss of P in surface runoff and leachate. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

A Freshwater Starvation Mechanism for Dansgaard-Oeschger Cycles

NASA Astrophysics Data System (ADS)

Wolff, E. W.; Hewitt, I.; Fowler, A.; Clark, C.; Evatt, G. W.; Munday, D. R.; Stokes, C.

2014-12-01

Many northern hemisphere climate records, particularly those from around the North Atlantic, show a series of rapid climate changes that recurred on centennial to millennial timescales throughout most of the last glacial period. These Dansgaard-Oeschger (D-O) sequences are observed most prominently in Greenland ice cores, although they have a global signature, including an out of phase Antarctic signal. They consist of warming jumps of order 10°C, occurring in typically 40 years, followed generally by a slow cooling (Greenland Interstadial, GI) lasting between a few centuries and a few millennia, and then a final rapid temperature drop into a cold Greenland Stadial (GS) that lasts for a similar period. The most distinctive feature of D-O cycles is the rapid warming event, often attributed to a sudden change in the strength of the Atlantic meridional overturning circulation (AMOC). Recent work has suggested that AMOC is most easily disrupted by freshwater delivered through the Arctic. We suggest that the proposed AMOC changes may have occurred as part of a natural oscillation, in which runoff from the Laurentide ice sheet into the Arctic is controlled by temperature around the North Atlantic. The Arctic buffers the salinity changes, but under warm conditions, high runoff eventually leads to water entering the North Atlantic with low enough salinity to switch AMOC into its weaker state. Under the colder conditions now prevailing, the Arctic is starved of runoff, and the salinity rises until a further switch occurs. Contrary to many previous studies, this mechanism does not require large freshwater pulses to the North Atlantic. Instead, steady changes in ice-sheet runoff, driven by the AMOC, lead to a naturally arising oscillator, in which the rapid warmings come about because the Arctic Ocean is starved of freshwater. The changing size of the ice sheets would have affected the magnitude and extent of runoff, and we suggest that this may provide a simple explanation for the absence of the events during interglacials and around the time of glacial maxima. Heinrich events, delivering additional freshwater into the Atlantic during a Greenland stadial, play no direct role in this mechanism, but would serve to delay the switch to faster AMOC.

Analysis of the runoff generation mechanism for the investigation of the SCS-CN method applicability to a partial area experimental watershed

NASA Astrophysics Data System (ADS)

Soulis, K. X.; Valiantzas, J. D.; Dercas, N.; Londra, P. A.

2009-01-01

The Soil Conservation Service Curve Number (SCS-CN) method is widely used for predicting direct runoff volume for a given rainfall event. The applicability of the SCS-CN method and the runoff generation mechanism were thoroughly analysed in a Mediterranean experimental watershed in Greece. The region is characterized by a Mediterranean semi-arid climate. A detailed land cover and soil survey using remote sensing and GIS techniques, showed that the watershed is dominated by coarse soils with high hydraulic conductivities, whereas a smaller part is covered with medium textured soils and impervious surfaces. The analysis indicated that the SCS-CN method fails to predict runoff for the storm events studied, and that there is a strong correlation between the CN values obtained from measured runoff and the rainfall depth. The hypothesis that this correlation could be attributed to the existence of an impermeable part in a very permeable watershed was examined in depth, by developing a numerical simulation water flow model for predicting surface runoff generated from each of the three soil types of the watershed. Numerical runs were performed using the HYDRUS-1D code. The results support the validity of this hypothesis for most of the events examined where the linear runoff formula provides better results than the SCS-CN method. The runoff coefficient of this formula can be taken equal to the percentage of the impervious area. However, the linear formula should be applied with caution in case of extreme events with very high rainfall intensities. In this case, the medium textured soils may significantly contribute to the total runoff and the linear formula may significantly underestimate the runoff produced.

Investigation of the direct runoff generation mechanism for the analysis of the SCS-CN method applicability to a partial area experimental watershed

NASA Astrophysics Data System (ADS)

Soulis, K. X.; Valiantzas, J. D.; Dercas, N.; Londra, P. A.

2009-05-01

The Soil Conservation Service Curve Number (SCS-CN) method is widely used for predicting direct runoff volume for a given rainfall event. The applicability of the SCS-CN method and the direct runoff generation mechanism were thoroughly analysed in a Mediterranean experimental watershed in Greece. The region is characterized by a Mediterranean semi-arid climate. A detailed land cover and soil survey using remote sensing and GIS techniques, showed that the watershed is dominated by coarse soils with high hydraulic conductivities, whereas a smaller part is covered with medium textured soils and impervious surfaces. The analysis indicated that the SCS-CN method fails to predict runoff for the storm events studied, and that there is a strong correlation between the CN values obtained from measured runoff and the rainfall depth. The hypothesis that this correlation could be attributed to the existence of an impermeable part in a very permeable watershed was examined in depth, by developing a numerical simulation water flow model for predicting surface runoff generated from each of the three soil types of the watershed. Numerical runs were performed using the HYDRUS-1D code. The results support the validity of this hypothesis for most of the events examined where the linear runoff formula provides better results than the SCS-CN method. The runoff coefficient of this formula can be taken equal to the percentage of the impervious area. However, the linear formula should be applied with caution in case of extreme events with very high rainfall intensities. In this case, the medium textured soils may significantly contribute to the total runoff and the linear formula may significantly underestimate the runoff produced.

Rainfall intensity and phosphorus source effects on phosphorus transport in surface runoff from soil trays.

PubMed

Shigaki, Francirose; Sharpley, Andrew; Prochnow, Luis Ignacio

2007-02-01

Phosphorus runoff from agricultural fields amended with mineral fertilizers and manures has been linked to freshwater eutrophication. A rainfall simulation study was conducted to evaluate the effects of different rainfall intensities and P sources differing in water soluble P (WSP) concentration on P transport in runoff from soil trays packed with a Berks loam and grassed with annual ryegrass (Lolium multiflorum Lam.). Triple superphosphate (TSP; 79% WSP), low-grade super single phosphate (LGSSP; 50% WSP), North Carolina rock phosphate (NCRP; 0.5% WSP) and swine manure (SM; 70% WSP), were broadcast (100 kg total P ha-1) and rainfall applied at 25, 50 and 75 mm h-1 1, 7, 21, and 56 days after P source application. The concentration of dissolved reactive (DRP), particulate (PP), and total P (TP) was significantly (P<0.01) greater in runoff with a rainfall intensity of 75 than 25 mm h-1 for all P sources. Further, runoff DRP increased as P source WSP increased, with runoff from a 50 mm h-1 rain 1 day after source application having a DRP concentration of 0.25 mg L-1 for NCRP and 28.21 mg L-1 for TSP. In contrast, the proportion of runoff TP as PP was greater with low (39% PP for NCRP) than high WSP sources (4% PP for TSP) averaged for all rainfall intensities. The increased PP transport is attributed to the detachment and transport of undissolved P source particles during runoff. These results show that P source water solubility and rainfall intensity can influence P transport in runoff, which is important in evaluating the long-term risks of P source application on P transport in surface runoff.

Impacts of urbanization on nitrogen cycling and aerosol, surface and groundwater transport in semi-arid regions

NASA Astrophysics Data System (ADS)

Lohse, K. A.; Gallo, E.; Carlson, M.; Riha, K. M.; Brooks, P. D.; McIntosh, J. C.; Sorooshian, A.; Michalski, G. M.; Meixner, T.

2011-12-01

Semi-arid regions are experiencing disproportionate increases in human population and land transformation worldwide, taxing limited water resources and altering nitrogen (N) biogeochemistry. How the redistribution of water and N by urbanization affects semi-arid ecosystems and downstream water quality (e.g. drinking water) is unclear. Understanding these interactions and their feedbacks will be critical for developing science-based management strategies to sustain these limited resources. This is especially true in the US where some of the fastest growing urban areas are in semi-arid ecosystems, where N and water cycles are accelerated, and intimately coupled, and where runoff from urban ecosystems is actively managed to augment a limited water supply to the growing human population. Here we synthesize several ongoing studies from the Tucson Basin in Arizona and examine how increasing urban land cover is altering rainfall-runoff relationships, groundwater recharge, water quality, and long range transport of atmospheric N. Studies across 5 catchments varying in impervious land cover showed that only the least impervious catchment responded to antecedent moisture conditions while hydrologic responses were not statistically related to antecedent rainfall conditions at more impervious sites. Regression models indicated that rainfall depth, imperviousness, and their combined effect control discharge and runoff ratios (p < 0.01, r2 = 0.91 and 0.75, respectively). In contrast, runoff quality was not predictably related to imperviousness or catchment size. Rather, rainfall depth and duration, time since antecedent rainfall, and stream channel characteristics and infrastructure controlled runoff chemistry. Groundwater studies showed nonpoint source contamination of CFCs and associated nitrate in areas of rapid recharge along ephemeral channels. Aerosol measurements indicate that both long-range transport of N and N emissions from Tucson are being transported and deposited at high elevation in areas that recharge regional groundwater. Combined, our findings suggest that urbanization in semi-arid regions results in tradeoffs in the redistribution of water and N that have important implications for water management and sustaining water quality.

Inverse Modeling of Hydrologic Parameters Using Surface Flux and Runoff Observations in the Community Land Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Yu; Hou, Zhangshuan; Huang, Maoyi

2013-12-10

This study demonstrates the possibility of inverting hydrologic parameters using surface flux and runoff observations in version 4 of the Community Land Model (CLM4). Previous studies showed that surface flux and runoff calculations are sensitive to major hydrologic parameters in CLM4 over different watersheds, and illustrated the necessity and possibility of parameter calibration. Two inversion strategies, the deterministic least-square fitting and stochastic Markov-Chain Monte-Carlo (MCMC) - Bayesian inversion approaches, are evaluated by applying them to CLM4 at selected sites. The unknowns to be estimated include surface and subsurface runoff generation parameters and vadose zone soil water parameters. We find thatmore » using model parameters calibrated by the least-square fitting provides little improvements in the model simulations but the sampling-based stochastic inversion approaches are consistent - as more information comes in, the predictive intervals of the calibrated parameters become narrower and the misfits between the calculated and observed responses decrease. In general, parameters that are identified to be significant through sensitivity analyses and statistical tests are better calibrated than those with weak or nonlinear impacts on flux or runoff observations. Temporal resolution of observations has larger impacts on the results of inverse modeling using heat flux data than runoff data. Soil and vegetation cover have important impacts on parameter sensitivities, leading to the different patterns of posterior distributions of parameters at different sites. Overall, the MCMC-Bayesian inversion approach effectively and reliably improves the simulation of CLM under different climates and environmental conditions. Bayesian model averaging of the posterior estimates with different reference acceptance probabilities can smooth the posterior distribution and provide more reliable parameter estimates, but at the expense of wider uncertainty bounds.« less

Inverse modeling of hydrologic parameters using surface flux and runoff observations in the Community Land Model

NASA Astrophysics Data System (ADS)

Sun, Y.; Hou, Z.; Huang, M.; Tian, F.; Leung, L. Ruby

2013-12-01

This study demonstrates the possibility of inverting hydrologic parameters using surface flux and runoff observations in version 4 of the Community Land Model (CLM4). Previous studies showed that surface flux and runoff calculations are sensitive to major hydrologic parameters in CLM4 over different watersheds, and illustrated the necessity and possibility of parameter calibration. Both deterministic least-square fitting and stochastic Markov-chain Monte Carlo (MCMC)-Bayesian inversion approaches are evaluated by applying them to CLM4 at selected sites with different climate and soil conditions. The unknowns to be estimated include surface and subsurface runoff generation parameters and vadose zone soil water parameters. We find that using model parameters calibrated by the sampling-based stochastic inversion approaches provides significant improvements in the model simulations compared to using default CLM4 parameter values, and that as more information comes in, the predictive intervals (ranges of posterior distributions) of the calibrated parameters become narrower. In general, parameters that are identified to be significant through sensitivity analyses and statistical tests are better calibrated than those with weak or nonlinear impacts on flux or runoff observations. Temporal resolution of observations has larger impacts on the results of inverse modeling using heat flux data than runoff data. Soil and vegetation cover have important impacts on parameter sensitivities, leading to different patterns of posterior distributions of parameters at different sites. Overall, the MCMC-Bayesian inversion approach effectively and reliably improves the simulation of CLM under different climates and environmental conditions. Bayesian model averaging of the posterior estimates with different reference acceptance probabilities can smooth the posterior distribution and provide more reliable parameter estimates, but at the expense of wider uncertainty bounds.

Transport mechanisms of Silver Nanoparticles by runoff - A Flume Experiment

NASA Astrophysics Data System (ADS)

Mahdi Mahdi, Karrar NM; Commelin, Meindert; Peters, Ruud J. B.; Baartman, Jantiene E. M.; Ritsema, Coen; Geissen, Violette

2017-04-01

Silver Nanoparticles (AgNPs) are being used in many products as it has unique antimicrobial-biocidal properties. Through leaching, these particles will reach the soil environment which may affect soil organisms and disrupt plants. This work aims to study the potential transport of AgNPs with water and sediment over the soil surface due to soil erosion by water. This was done in a laboratory setting, using a rainfall simulator and flume. Low AgNPs concentration (50 μg.kg-1) was applied to two soil-flumes with slopes of 20% and 10%. The rainfall was applied in four events of 15 min each with the total amount of rainfall was 15mm in each event. After applying the rainfall, different samples were collected; soil clusters, background (BS) and surface sediments (Sf), from the flume surface, and, Runoff sediments (RS) and water (RW) was collected from the outlet. The results showed that AgNPs were detected in all samples collected, however, AgNPs concentration varied according samples type (soil or water), time of collection (for runoff water and sediment) and the slope of the soil flume. Further, the higher AgNPs concentrations were detected in the background soil (BS); as the BS samples have more finer parts (silt and clay). The AgNPs concentration in the runoff sediments increased with subsequent applied rain events. In addition to that, increasing the slope of the flume from 10% to 20% increased the total AgNPs transported with the runoff sediments by a factor 1.5. The study confirms that AgNPs can be transported over the soil surface by both runoff water and sediments due to erosion.

Relating runoff generation mechanisms to concentration-discharge relationships in catchments with well-characterized Critical Zone structures and hydrologic dynamics

NASA Astrophysics Data System (ADS)

Hahm, W. J.; Wang, J.; Druhan, J. L.; Rempe, D.; Dietrich, W. E.

2017-12-01

Stream solute concentration-discharge (C-Q) relationships integrate catchment-scale hydrologic and geochemical processes, potentially yielding valuable information about runoff generation and weathering mechanisms. However, recent compilations have established that chemostasis—the condition where solute concentrations are invariant across large ranges of runoff—is observed in watersheds of diverse lithology, climate, and topography, suggesting an equifinality of the C-Q relationship independent of hydrologic process. Here we explore C-Q signals in contrasting catchments of the Eel River Critical Zone (CZ) Observatory in the Northern California Coast Ranges, where, unlike most watersheds where chemostasis has been observed, hillslope hydrologic processes are well characterized via years of intensive hydrologic monitoring. Our two catchments in the Franciscan Complex have radically different runoff generation mechanisms arising from differences in CZ structure: at Elder Creek (Coastal Belt), rain passes vertically as unsaturated flow through soil, saprolite, and a thick weathered rock zone before perching as groundwater on fresh bedrock and flowing laterally through fractures to generate streamflow, resulting in nearly chemostatic major cation behavior (power law C-Q slopes (B) ≈ 0 to -0.1). At Dry Creek (Central Belt), the thin (2 to 3 m) hydrologically active CZ completely saturates in most storm events, generating saturation overland flow across the landscape. New data from Dry Creek reveal log-log C-Q relationships for major cations that exhibit negative curvature, indicating a trend towards increasing dilution at higher flow rates and a possible C-Q signature of overland flow. High geomorphic channel drainage density (16.9 km/km2) results in short flow paths and, presumably, short water hillslope residence times at high runoff when overland flow dominates (> 50 mm d-1). Surprisingly, even at these high runoff rates, pure dilution does not occur (high runoff B ≈ -0.5), suggesting a role for extremely rapid cation exchange reactions and equilibration as water flows over and through the soil surface, and underscoring limitations on the ability to interpret hydrologic processes from C-Q behavior.

Spatial and temporal patterns of pesticide losses in a small Swedish agricultural catchment

NASA Astrophysics Data System (ADS)

Sandin, Maria; Piikki, Kristin; Jarvis, Nicholas; Larsbo, Mats; Bishop, Kevin; Kreuger, Jenny

2017-04-01

Research at catchment and regional scales shows that losses of pesticides to surface water often originate from a relatively small fraction of the agricultural landscape. These 'hydrologic source areas' represent areas of land that are highly susceptible to fast transport processes, primarily surface runoff or rapid subsurface flows through soil macropores, either to subsurface field drainage systems or as shallow interflow on more strongly sloping land. A good understanding of the nature of transport pathways for pesticides to surface water in agricultural landscapes is essential for cost-effective identification and implementation of mitigation measures. However, the relative importance of surface and subsurface flows for transport of pesticides to surface waters in Sweden remains largely unknown, since very few studies have been performed under Swedish agro-environmental conditions. We conducted a monitoring study in a small sub-surface drained agricultural catchment in one of the main crop production regions in Sweden. Three small sub-catchments were selected for water sampling based on a high-resolution soil map developed from proximal sensing data; one sub-catchment was dominated by clay soils, another by coarse sandy soils while the third comprised a mix of soil types. Samples were collected from the stream, from field drains discharging into the stream and from within-field surface runoff during spring and early summer in three consecutive years. LC-MS/MS analyses of more than 100 compounds, covering the majority of the polar and semi-polar pesticides most frequently used in Swedish agriculture, were performed on all samples using accredited methods. Information on pesticide applications (products, doses and timing) was obtained from annual interviews with the farmers. There were clear and consistent differences in pesticide losses between the three sub-catchments, with the largest losses occurring in the area with clay soils, and negligible losses from the sandy sub-catchment. This suggests that transport of pesticides to the stream is almost entirely occurring along fast flow paths such as macropore flow to drains or surface runoff. Only a very small proportion of fields are directly connected to the stream by overland pathways, which suggests that macropore flow to drains was the dominant loss pathway in the studied area. Data on pesticide use patterns revealed that compounds were detected in drainage and stream water samples that had not been applied for several years. This suggests that despite the predominant role of fast flow paths in determining losses to the stream, long-term storage along the transport pathways also occurs, presumably in subsoil where degradation is slow.

Application of SWAT-HS, a lumped hillslope model to simulate hydrology in the Cannonsville Reservoir watershed, New York

NASA Astrophysics Data System (ADS)

Hoang, Linh; Schneiderman, Elliot; Mukundan, Rajith; Moore, Karen; Owens, Emmet; Steenhuis, Tammo

2017-04-01

Surface runoff is the primary mechanism transporting substances such as sediments, agricultural chemicals, and pathogens to receiving waters. In order to predict runoff and pollutant fluxes, and to evaluate management practices, it is essential to accurately predict the areas generating surface runoff, which depend on the type of runoff: infiltration-excess runoff and saturation-excess runoff. The watershed of Cannonsville reservoir is part of the New York City water supply system that provides high quality drinking water to nine million people in New York City (NYC) and nearby communities. Previous research identified saturation-excess runoff as the dominant runoff mechanism in this region. The Soil and Water Assessment Tool (SWAT) is a promising tool to simulate the NYC watershed given its broad application and good performance in many watersheds with different scales worldwide, for its ability to model water quality responses, and to evaluate the effect of management practices on water quality at the watershed scale. However, SWAT predicts runoff based mainly on soil and land use characteristics, and implicitly considers only infiltration-excess runoff. Therefore, we developed a modified version of SWAT, referred to as SWAT-Hillslope (SWAT-HS), which explicitly simulates saturation-excess runoff by redefining Hydrological Response Units (HRUs) based on wetness classes with varying soil water storage capacities, and by introducing a surface aquifer with the ability to route interflow from "drier" to "wetter" wetness classes. SWAT-HS was first tested at Town Brook, a 37 km2 headwater watershed draining to the Cannonsville reservoir using a single sub-basin for the whole watershed. SWAT-HS performed well, and predicted streamflow yielded Nash-Sutcliffe Efficiencies of 0.68 and 0.87 at the daily and monthly time steps, respectively. More importantly, it predicted the spatial distribution of saturated areas accurately. Based on the good performance in the Town Brook watershed, we scale-up the application of SWAT-HS to the 1160 km2 Cannonsville watershed utilizing a setup of multiple sub-basins, and evaluate the model performance on flow simulation at different gauged locations in the watershed. Results from flow predictions will be used as a basis for evaluating the ability of SWAT-HS to make sediment and nutrient loading estimates.

Phosphorus transfer in runoff following application of fertilizer, manure, and sewage sludge.

PubMed

Withers, P J; Clay, S D; Breeze, V G

2001-01-01

Phosphorus (P) transfer in surface runoff from field plots receiving either no P, triplesuperphoshate (TSP), liquid cattle manure (LCS), liquid anaerobically digested sludge (LDS), or dewatered sludge cake (DSC) was compared over a 2-yr period. Dissolved inorganic P concentrations in runoff increased from 0.1 to 0.2 mg L(-1) on control and sludge-treated plots to 3.8 and 6.5 mg L(-1) following application of LCS and TSP, respectively, to a cereal crop in spring. When incorporated into the soil in autumn, runoff dissolved P concentrations were typically < 0.5 mg L(-1) across all plots, and particulate P remained the dominant P form. When surface-applied in autumn to a consolidated seedbed, direct loss of LCS and LDS increased both runoff volume and P transfers, but release of dissolved P occurred only from LCS. The largest P concentrations (>70 mg L(-1)) were recorded following TSP application without any increase in runoff volume, while application of bulky DSC significantly reduced total P transfers by 70% compared with the control due to a reduced runoff volume. Treatment effects in each monitoring period were most pronounced in the first runoff event. Differences in the release of P from the different P sources were related to the amounts of P extracted by either water or sodium bicarbonate in the order TSP > LCS > LDS > DSC. The results suggest there is a lower risk of P transfer in land runoff following application of sludge compared with other agricultural P amendments at similar P rates.

Surface-rain interactions: differences in copper runoff for copper sheet of different inclination, orientation, and atmospheric exposure conditions.

PubMed

Hedberg, Yolanda S; Goidanich, Sara; Herting, Gunilla; Wallinder, Inger Odnevall

2015-01-01

Predictions of the diffuse dispersion of metals from outdoor constructions such as roofs and facades are necessary for environmental risk assessment and management. An existing predictive model has been compared with measured data of copper runoff from copper sheets exposed at four different inclinations facing four orientations at two different urban sites (Stockholm, Sweden, and Milan, Italy) during a 4-year period. Its applicability has also been investigated for copper sheet exposed at two marine sites(Cadiz, Spain, for 5 years, and Brest, France, for 9 years). Generally the model can be used for all given conditions. However, vertical surfaces should be considered as surfaces inclined 60-80 due to wind driven effects. The most important parameters that influence copper runoff, and not already included in the model, are the wind and rain characteristics that influence the actual rainfall volume impinging the surface of interest.

Evaluating the impact of climate and underlying surface on runoff change within Budyko framework: a study across 224 catchments in China

NASA Astrophysics Data System (ADS)

Shen, Q.; Cong, Z.; Lei, H.

2017-12-01

Climate change and underlying surface change are two main factors affecting the hydrological cycle. In respect of climate change, precipitation alters not only in magnitude, but also in intensity, which can be represented by the precipitation depth. To further understand the spatial variation of the impact of precipitation, potential evapotranspiration, precipitation depth as well as the water storage capacity, in this paper 224 catchments across China were analyzed applying the Choudhury-Porporato equation based on the Budyko hypothesis. The catchments distribute in 9 major basins in China and the study period is from 1960 to 2010. The results show that underlying surface is the major driving force of the change in runoff in the Songhua Basin, the Liaohe Basin and the Haihe Basin, while climate change dominates runoff change in other basins. Climate change causes runoff increase in most catchments, except for some catchments in the Yellow River Basin and the Yangtze River Basin. Specifically, change in precipitation depth induces runoff increase in almost each catchment and shows a remarkable contribution rate (14.8% on average, larger than 20% in 32% catchments). The contribution of precipitation depth has little correlation with the aridity index, while positively correlates to the significance of trend in precipitation depth. This study suggests that precipitation depth is an important aspect that should be taken into consideration in attribution of runoff change. The results can give a sight for future researches in attribution analysis within the Budyko framework.

Soil aggregate stability and size-selective sediment transport with surface runoff as affected by organic residue amendment.

PubMed

Shi, Pu; Arter, Christian; Liu, Xingyu; Keller, Martin; Schulin, Rainer

2017-12-31

Aggregate breakdown influences the availability of soil particles for size-selective sediment transport with surface runoff during erosive rainfall events. Organic matter management is known to affect aggregate stability against breakdown, but little is known about how this translates into rainfall-induced aggregate fragmentation and sediment transport under field conditions. In this study, we performed field experiments in which artificial rainfall was applied after pre-wetting on three pairs of arable soil plots (1.5×0.75m) six weeks after incorporating a mixture of grass and wheat straw into the topsoil of one plot in each pair (OI treatment) but not on the other plot (NI treatment). Artificial rainfall was applied for approximately 2h on each pair at an intensity of 49.1mmh -1 . In both treatments, discharge and sediment concentration in the discharge were correlated and followed a similar temporal pattern after the onset of surface runoff: After a sharp increase at the beginning both approached a steady state. But the onset of runoff was more delayed on the OI plots, and the discharge and sediment concentration were in average only roughly half as high on the OI as on the NI plots. With increasing discharge the fraction of coarse sediment increased. This relationship did not differ between the two treatments. Thus, due to the lower discharge, the fraction of fine particles in the exported sediment was larger in the runoff from the OI plots than from the NI plots. The later runoff onset and lower discharge rate was related to a higher initial aggregate stability on the OI plots. Terrestrial laser scanning proved to be a very valuable method to map changes in the micro-topography of the soil surfaces. It revealed a much less profound decrease in surface roughness on the OI than on the NI plots. Copyright © 2017 Elsevier B.V. All rights reserved.

Regional Analysis of Stormwater Runoff for the Placement of Managed Aquifer Recharge Sites in Santa Cruz and Northern Monterey Counties, California

NASA Astrophysics Data System (ADS)

Young, K. S.; Beganskas, S.; Fisher, A. T.

2015-12-01

We apply a USGS surface hydrology model, Precipitation-Runoff Modeling System (PRMS), to analyze stormwater runoff in Santa Cruz and Northern Monterey Counties, CA with the goal of supplying managed aquifer recharge (MAR) sites. Under the combined threats of multiyear drought and excess drawdown, this region's aquifers face numerous sustainability challenges, including seawater intrusion, chronic overdraft, increased contamination, and subsidence. This study addresses the supply side of this resource issue by increasing our knowledge of the spatial and temporal dynamics of runoff that could provide water for MAR. Ensuring the effectiveness of MAR using stormwater requires a thorough understanding of runoff distribution and site-specific surface and subsurface aquifer conditions. In this study we use a geographic information system (GIS) and a 3-m digital elevation model (DEM) to divide the region's four primary watersheds into Hydrologic Response Units (HRUs), or topographic sub-basins, that serve as discretized input cells for PRMS. We then assign vegetation, soil, land use, slope, aspect, and other characteristics to these HRUs, from a variety of data sources, and analyze runoff spatially using PRMS under varying precipitation conditions. We are exploring methods of linking spatially continuous and high-temporal-resolution precipitation datasets to generate input precipitation catalogs, facilitating analyses of a variety of regimes. To gain an understanding of how surface hydrology has responded to land development, we will also modify our input data to represent pre-development conditions. Coupled with a concurrent MAR suitability analysis, our model results will help screen for locations of future MAR projects and will improve our understanding of how changes in land use and climate impact hydrologic runoff and aquifer recharge.

Origins and transport of aquatic dioxins in the Japanese watershed: soil contamination, land use, and soil runoff events.

PubMed

Kanematsu, Masakazu; Shimizu, Yoshihisa; Sato, Keisuke; Kim, Suejin; Suzuki, Tasuma; Park, Baeksoo; Saino, Reiko; Nakamura, Masafumi

2009-06-15

Significant dioxins accumulations in Japanese forests and paddy fields have been observed, and surface soil runoff caused by rainfall and irrigation (i.e., soil puddling in paddy fields) results in dioxins input into the aquatic environment. An extensive investigation into the origins and transport of aquatic dioxins in the Yasu watershed, Japan was conducted considering surface soil contamination level, land use, and type of soil runoff event (i.e., irrigation runoff [IR], rainfall runoff [RR], and base flow [BF]). Combined use of the chemically activated luciferase expression (CALUX) assay together with high-resolution gas chromatography and high-resolution mass spectrometry (HRGC/HRMS) efficiently enabled this study, so that origins, transport, and dynamic movement of aquatic dioxins in the watershed were revealed. The particulate organic carbon normalized particulate-dioxins WHO-toxic equivalent (TEQ) concentration predicted by the CALUX assay (Spar) was found to be a convenient molecular marker to indicate origins of aquatic dioxins and clearly reflect surface soil contamination level, land use, and soil runoff events. Using experimental results and theoretical modeling, the annual loading amount of dioxins at the middle reach of the river was estimated to be 0.458 mg WHO-TEQ in 2004. More than 96.6% of the annual loading amount was attributed to RR and derived almost evenly from forest and paddy fields at the study location. Because the annual loading amount at the middle reach is less than 0.5% of the total dioxins accumulated in the upper basin, dioxins runoff from the Japanese watershed will continue. This study shows that the combined use of the bioassay with HRGC/HRMS can provide new insights into dioxins transport and fate in the environment.

Surface Runoff Estimation Using SMOS Observations, Rain-gauge Measurements and Satellite Precipitation Estimations. Comparison with Model Predictions

NASA Astrophysics Data System (ADS)

Garcia Leal, Julio A.; Lopez-Baeza, Ernesto; Khodayar, Samiro; Estrela, Teodoro; Fidalgo, Arancha; Gabaldo, Onofre; Kuligowski, Robert; Herrera, Eddy

Surface runoff is defined as the amount of water that originates from precipitation, does not infiltrates due to soil saturation and therefore circulates over the surface. A good estimation of runoff is useful for the design of draining systems, structures for flood control and soil utilisation. For runoff estimation there exist different methods such as (i) rational method, (ii) isochrone method, (iii) triangular hydrograph, (iv) non-dimensional SCS hydrograph, (v) Temez hydrograph, (vi) kinematic wave model, represented by the dynamics and kinematics equations for a uniforme precipitation regime, and (vii) SCS-CN (Soil Conservation Service Curve Number) model. This work presents a way of estimating precipitation runoff through the SCS-CN model, using SMOS (Soil Moisture and Ocean Salinity) mission soil moisture observations and rain-gauge measurements, as well as satellite precipitation estimations. The area of application is the Jucar River Basin Authority area where one of the objectives is to develop the SCS-CN model in a spatial way. The results were compared to simulations performed with the 7-km COSMO-CLM (COnsortium for Small-scale MOdelling, COSMO model in CLimate Mode) model. The use of SMOS soil moisture as input to the COSMO-CLM model will certainly improve model simulations.

Oceanic Transport of Surface Meltwater from the Southern Greenland Ice Sheet

NASA Technical Reports Server (NTRS)

Luo, Hao; Castelao, Renato M.; Rennermalm, Asa K.; Tedesco, Marco; Bracco, Annalisa; Yager, Patricia L.; Mote, Thomas L.

2016-01-01

The Greenland ice sheet has undergone accelerating mass losses during recent decades. Freshwater runoff from ice melt can influence fjord circulation and dynamic1 and the delivery of bioavailable micronutrients to the ocean. It can also have climate implications, because stratification in the adjacent Labrador Sea may influence deep convection and the strength of the Atlantic meridional overturning circulation. Yet, the fate of the meltwater in the ocean remains unclear. Here, we use a high-resolution ocean model to show that only 1-15% of the surface meltwater runoff originating from southwest Greenland is transported westwards. In contrast, up to 50-60% of the meltwater runoff originating from southeast Greenland is transported westwards into the northern Labrador Sea, leading to significant salinity and stratification anomalies far from the coast. Doubling meltwater runoff, as predicted in future climate scenarios, results in a more-than-double increase in anomalies offshore that persists further into the winter. Interannual variability in offshore export of meltwater is tightly related to variability in wind forcing. The new insight that meltwaters originating from the west and east coasts have different fates indicates that future changes in mass loss rates and surface runoff will probably impact the ocean differently, depending on their Greenland origins.

Off-site transport of nitrogen fertilizer with runoff from golf course fairway turf: A comparison of creeping bentgrass with a fine fescue mixture.

PubMed

Rice, Pamela J; Horgan, Brian P

2017-02-15

Maintaining quality golf course turf often requires irrigation and application of fertilizer. The transport of excess nutrients with runoff water from highly managed and fertilized biological systems to surrounding surface waters has been shown to result in enhanced algal blooms and promotion of eutrophication. Environmental stewardship includes looking for new approaches to reduce adverse environmental impacts of current practices. One strategy is to replace traditional turfgrass with low-maintenance turfgrass species. Fescue grasses have been shown to provide characteristics desirable for golf course fairways. Thus side-by-side studies comparing runoff from plots planted in creeping bentgrass (CGB) or fine fescue mixture (FFM), similarly managed as a golf course fairway, were conducted to measure runoff volumes and the amount of ammonium nitrogen (NH 4 -N) and nitrate nitrogen (NO 3 -N) transported off-site with runoff. Greater runoff volumes and mass of applied nutrients were measured in the runoff from the FFM, representing a 38% and 56% median increase in the off-site mass transport of NH 4 -N and NO 3 -N with surface flow. Shoot density, thatch depth and soil moisture were the most important factors related to runoff volume. Results of this research will be useful to grounds superintendents and researchers for selecting and developing management strategies to improve environmental stewardship of managed turf while providing desired turf quality. Published by Elsevier B.V.

Intra-basin variability of snowmelt water balance calculations in a subarctic catchment

NASA Astrophysics Data System (ADS)

McCartney, Stephen E.; Carey, Sean K.; Pomeroy, John W.

2006-03-01

The intra-basin variability of snowmelt and melt-water runoff hydrology in an 8 km2 subarctic alpine tundra catchment was examined for the 2003 melt period. The catchment, Granger Creek, is within the Wolf Creek Research Basin, Yukon, which is typical of mountain subarctic landscapes in northwestern Canada. The study catchment was segmented into nine internally uniform zones termed hydrological response units (HRUs) based on their similar hydrological, physiographic, vegetation and soil properties. Snow accumulation exhibited significant variability among the HRUs, with greatest snow water equivalent in areas of tall shrub vegetation. Melt began first on southerly exposures and at lower elevations, yet average melt rates for the study period varied little among HRUs with the exception of those with steep aspects. In HRUs with capping organic soils, melt water first infiltrated this surface horizon, satisfying its storage capacity, and then percolated into the frozen mineral substrate. Infiltration and percolation into frozen mineral soils was restricted where melt occurred rapidly and organic soils were thin; in this case, melt-water delivery rates exceeded the frozen mineral soil infiltration rate, resulting in high runoff rates. In contrast, where there were slower melt rates and thick organic soils, infiltration was unlimited and runoff was suppressed. The snow water equivalent had a large impact on runoff volume, as soil storage capacity was quickly surpassed in areas of deep snow, diverting the bulk of melt water laterally to the drainage network. A spatially distributed water balance indicated that the snowmelt freshet was primarily controlled by areas with tall shrub vegetation that accumulate large quantities of snow and by alpine areas with no capping organic soils. The intra-basin water balance variability has important implications for modelling freshet in hydrological models.

High Resolution Simulation of a Colorado Rockies Extreme Snow and Rain Event in both a Current and Future Climate

NASA Astrophysics Data System (ADS)

Rasmussen, Roy; Ikeda, Kyoko; Liu, Changhai; Gutmann, Ethan; Gochis, David

2016-04-01

Modeling of extreme weather events often require very finely resolved treatment of atmospheric circulation structures in order to produce and localize the large moisture fluxes that result in extreme precipitation. This is particularly true for cool season orographic precipitation processes where the representation of the landform can significantly impact vertical velocity profiles and cloud moisture entrainment rates. This study presents results for high resolution regional climate modeling study of the Colorado Headwaters region using an updated version of the Weather Research and Forecasting (WRF) model run at 4 km horizontal resolution and a hydrological extension package called WRF-Hydro. Previous work has shown that the WRF modeling system can produce credible depictions of winter orographic precipitation over the Colorado Rockies if run at horizontal resolutions < 6 km. Here we present results from a detailed study of an extreme springtime snowfall event that occurred along the Colorado Front Range in March 2003. Results from the impact of warming on total precipitation, snow-rain partitioning and surface hydrological fluxes (evapotranspiration and runoff) will be discussed in the context of how potential changes in temperature impact the amount of precipitation, the phase of precipitation (rain vs. snow) and the timing and amplitude of streamflow responses. The results show using the Pseudo Global Warming technique that intense precipitation rates significantly increased during the event and a significant fraction of the snowfall converts to rain which significantly amplifies the runoff response from one where runoff is produced gradually to one in which runoff is rapidly translated into streamflow values that approach significant flooding risks. Results from a new, CONUS scale high resolution climate simulation of extreme events in a current and future climate will be presented as time permits.

Dam nation: A geographic census of American dams and their large-scale hydrologic impacts

NASA Astrophysics Data System (ADS)

Graf, William L.

1999-04-01

Newly available data indicate that dams fragment the fluvial system of the continental United States and that their impact on river discharge is several times greater than impacts deemed likely as a result of global climate change. The 75,000 dams in the continental United States are capable of storing a volume of water almost equaling one year's mean runoff, but there is considerable geographic variation in potential surface water impacts. In some western mountain and plains regions, dams can store more than 3 year's runoff, while in the Northeast and Northwest, storage is as little as 25% of the annual runoff. Dams partition watersheds; the drainage area per dam varies from 44 km2 (17 miles2) per dam in New England to 811 km2 (313 miles2) per dam in the Lower Colorado basin. Storage volumes, indicators of general hydrologic effects of dams, range from 26,200 m3 km-2 (55 acre-feet mile-2) in the Great Basin to 345,000 m3 km-2 (725 acre-feet mile-2) in the South Atlantic region. The greatest river flow impacts occur in the Great Plains, Rocky Mountains, and the arid Southwest, where storage is up to 3.8 times the mean annual runoff. The nation's dams store 5000 m3 (4 acre-feet) of water per person. Water resource regions have experienced individualized histories of cumulative increases in reservoir storage (and thus of downstream hydrologic and ecologic impacts), but the most rapid increases in storage occurred between the late 1950s and the late 1970s. Since 1980, increases in storage have been relatively minor.

Tracing hydrologic pathways at the Panola Mountain research watershed, Georgia, USA

USGS Publications Warehouse

Peters, N.E.; Ratcliffe, E.B.

1997-01-01

An analysis of Cl- concentrations and fluxes at the Panola Mountain Research Watershed indicates that Cl- may be effectively used to differentiate 'new' and 'old' water flow through the hillslope and their respective contributions to streamwater. Rainfall and throughfall, the 'new' water inputs, are marked by low Cl- concentrations (15 ??eq 1-1). Stormwater moves rapidly to depth along preferred pathways in a deciduous forest hillslope, as evidenced by low concentrations (20 ??eq 1-1) in mobile soil water from zero-tension stainless-steel pan lysimeters. 'Old' waters, matrix soil waters and groundwater, typically have high concentrations (20 ??eq 1-1). Timing of soil water transport is not sufficiently rapid to suggest that soil water from the hillslope contributes to streamwater for an individual rainstorm. The source of streamflow, therefore, must be a combination of channel interception, runoff from near-channel areas, and runoff from a 3-ha bedrock outcrop in the headwaters. Groundwater contribution to streamflow was estimated using Cl- concentrations of throughfall and groundwater as the two end members for a two-component hydrograph separation. For the study period, groundwater contributed 79% of the runoff and from 1985 to 1995, contributed 75% of the runoff. Rainfall was the source of 45% of the Cl- flux from the watershed in the long term; the remaining Cl- is hypothesized to be derived from dry deposition, consistent with the enrichment noted for throughfall. At peak flow during individual rainstorms, 'new' water can contribute 95% of the runoff.

Computer program for simulation of variable recharge with the U. S. Geological Survey modular finite-difference ground-water flow model (MODFLOW)

USGS Publications Warehouse

Kontis, A.L.

2001-01-01

The Variable-Recharge Package is a computerized method designed for use with the U.S. Geological Survey three-dimensional finitedifference ground-water flow model (MODFLOW-88) to simulate areal recharge to an aquifer. It is suitable for simulations of aquifers in which the relation between ground-water levels and land surface can affect the amount and distribution of recharge. The method is based on the premise that recharge to an aquifer cannot occur where the water level is at or above land surface. Consequently, recharge will vary spatially in simulations in which the Variable- Recharge Package is applied, if the water levels are sufficiently high. The input data required by the program for each model cell that can potentially receive recharge includes the average land-surface elevation and a quantity termed ?water available for recharge,? which is equal to precipitation minus evapotranspiration. The Variable-Recharge Package also can be used to simulate recharge to a valley-fill aquifer in which the valley fill and the adjoining uplands are explicitly simulated. Valley-fill aquifers, which are the most common type of aquifer in the glaciated northeastern United States, receive much of their recharge from upland sources as channeled and(or) unchanneled surface runoff and as lateral ground-water flow. Surface runoff in the uplands is generated in the model when the applied water available for recharge is rejected because simulated water levels are at or above land surface. The surface runoff can be distributed to other parts of the model by (1) applying the amount of the surface runoff that flows to upland streams (channeled runoff) to explicitly simulated streams that flow onto the valley floor, and(or) (2) applying the amount that flows downslope toward the valley- fill aquifer (unchanneled runoff) to specified model cells, typically those near the valley wall. An example model of an idealized valley- fill aquifer is presented to demonstrate application of the method and the type of information that can be derived from its use. Documentation of the Variable-Recharge Package is provided in the appendixes and includes listings of model code and of program variables. Comment statements in the program listings provide a narrative of the code. Input-data instructions and printed model output for the package are included.

Nitrogen and phosphorus associating with different size suspended solids in roof and road runoff in Beijing, China.

PubMed

Wu, Junliang; Ren, Yufen; Wang, Xuemei; Wang, Xiaoke; Chen, Liding; Liu, Gangcai

2015-10-01

Roofs and roads, accounting for a large portion of the urban impervious land surface, have contributed significantly to urban nonpoint pollution. In this study, in Beijing, China, roof and road runoff are sampled to measure the suspended solids (SS), nitrogen (N), and phosphorus (P) contained in particles with different sizes. The SS content in the road runoff (151.59 mg/L) was sevenfold that in the roof runoff (21.13 mg/L, p < 0.05). The SS contained more coarse particulates in the roof runoff than in road runoff. The small particulates in the range of 0.45-50 μm consisted of 59 % SS in the roof runoff and 94 % SS in the road runoff. P was mainly attached to particle sizes of 10-50 μm in the roof (73 %) and road (48 %) runoffs, while N was mainly in a dissolved phase state in both runoffs. So, the different associations of N and P raise a challenge in preventing stormwater pollution in urban environments.

Application of MIKE SHE to study the impact of coal mining on river runoff in Gujiao mining area, Shanxi, China

PubMed Central

Ping, Jianhua; Yan, Shiyan; Gu, Pan; Wu, Zening; Hu, Caihong

2017-01-01

Coal mining is one of the core industries that contribute to the economic development of a country but deteriorate the environment. Being the primary source of energy, coal has become essential to meet the energy demand of a country. It is excavated by both opencast and underground mining methods and affects the environment, especially hydrological cycle, by discharging huge amounts of mine water. Natural hydrological processes have been well known to be vulnerable to human activities, especially large scale mining activities, which inevitably generate surface cracks and subsidence. It is therefore valuable to assess the impact of mining on river runoff for the sustainable development of regional economy. In this paper, the impact of coal mining on river runoff is assessed in one of the national key coal mining sites, Gujiao mining area, Shanxi Province, China. The characteristics of water cycle are described, the similarities and differences of runoff formation are analyzed in both coal mining and pre-mining periods. The integrated distributed hydrological model named MIKE SHE is employed to simulate and evaluate the influence of coal mining on river runoff. The study shows that mining one ton of raw coal leads to the reduction of river runoff by 2.87 m3 between 1981 and 2008, of which the surface runoff decreases by 0.24 m3 and the baseflow by 2.63 m3. The reduction degree of river runoff for mining one ton of raw coal shows an increasing trend over years. The current study also reveals that large scale coal mining initiates the formation of surface cracks and subsidence, which intercepts overland flow and enhances precipitation infiltration. Together with mine drainage, the natural hydrological processes and the stream flows have been altered and the river run off has been greatly reduced. PMID:29267313

Application of MIKE SHE to study the impact of coal mining on river runoff in Gujiao mining area, Shanxi, China.

PubMed

Ping, Jianhua; Yan, Shiyan; Gu, Pan; Wu, Zening; Hu, Caihong

2017-01-01

Coal mining is one of the core industries that contribute to the economic development of a country but deteriorate the environment. Being the primary source of energy, coal has become essential to meet the energy demand of a country. It is excavated by both opencast and underground mining methods and affects the environment, especially hydrological cycle, by discharging huge amounts of mine water. Natural hydrological processes have been well known to be vulnerable to human activities, especially large scale mining activities, which inevitably generate surface cracks and subsidence. It is therefore valuable to assess the impact of mining on river runoff for the sustainable development of regional economy. In this paper, the impact of coal mining on river runoff is assessed in one of the national key coal mining sites, Gujiao mining area, Shanxi Province, China. The characteristics of water cycle are described, the similarities and differences of runoff formation are analyzed in both coal mining and pre-mining periods. The integrated distributed hydrological model named MIKE SHE is employed to simulate and evaluate the influence of coal mining on river runoff. The study shows that mining one ton of raw coal leads to the reduction of river runoff by 2.87 m3 between 1981 and 2008, of which the surface runoff decreases by 0.24 m3 and the baseflow by 2.63 m3. The reduction degree of river runoff for mining one ton of raw coal shows an increasing trend over years. The current study also reveals that large scale coal mining initiates the formation of surface cracks and subsidence, which intercepts overland flow and enhances precipitation infiltration. Together with mine drainage, the natural hydrological processes and the stream flows have been altered and the river run off has been greatly reduced.

Impact of the hard-coded parameters on the hydrologic fluxes of the land surface model Noah-MP

NASA Astrophysics Data System (ADS)

Cuntz, Matthias; Mai, Juliane; Samaniego, Luis; Clark, Martyn; Wulfmeyer, Volker; Attinger, Sabine; Thober, Stephan

2016-04-01

Land surface models incorporate a large number of processes, described by physical, chemical and empirical equations. The process descriptions contain a number of parameters that can be soil or plant type dependent and are typically read from tabulated input files. Land surface models may have, however, process descriptions that contain fixed, hard-coded numbers in the computer code, which are not identified as model parameters. Here we searched for hard-coded parameters in the computer code of the land surface model Noah with multiple process options (Noah-MP) to assess the importance of the fixed values on restricting the model's agility during parameter estimation. We found 139 hard-coded values in all Noah-MP process options, which are mostly spatially constant values. This is in addition to the 71 standard parameters of Noah-MP, which mostly get distributed spatially by given vegetation and soil input maps. We performed a Sobol' global sensitivity analysis of Noah-MP to variations of the standard and hard-coded parameters for a specific set of process options. 42 standard parameters and 75 hard-coded parameters were active with the chosen process options. The sensitivities of the hydrologic output fluxes latent heat and total runoff as well as their component fluxes were evaluated. These sensitivities were evaluated at twelve catchments of the Eastern United States with very different hydro-meteorological regimes. Noah-MP's hydrologic output fluxes are sensitive to two thirds of its standard parameters. The most sensitive parameter is, however, a hard-coded value in the formulation of soil surface resistance for evaporation, which proved to be oversensitive in other land surface models as well. Surface runoff is sensitive to almost all hard-coded parameters of the snow processes and the meteorological inputs. These parameter sensitivities diminish in total runoff. Assessing these parameters in model calibration would require detailed snow observations or the calculation of hydrologic signatures of the runoff data. Latent heat and total runoff exhibit very similar sensitivities towards standard and hard-coded parameters in Noah-MP because of their tight coupling via the water balance. It should therefore be comparable to calibrate Noah-MP either against latent heat observations or against river runoff data. Latent heat and total runoff are sensitive to both, plant and soil parameters. Calibrating only a parameter sub-set of only soil parameters, for example, thus limits the ability to derive realistic model parameters. It is thus recommended to include the most sensitive hard-coded model parameters that were exposed in this study when calibrating Noah-MP.

Landslide-induced weathering: insight from a deep bedrock tunnel in Taiwan and implications for the carbon cycle

NASA Astrophysics Data System (ADS)

Martin, C. E.; Galy, A.; Calmels, D.; Hovius, N.; Bickle, M.; Chen, M.

2012-12-01

We present new groundwater chemistry data from inside a 520 m-long, un-cased bedrock tunnel in Taroko Gorge, Taiwan. The tunnel cuts through a ~ 250 m ridge of steeply-dipping meta-sediments (schists and marbles) and exhibits water flow characteristic of deep groundwater and slow surface runoff as defined by Calmels et al. (2011). For comparison, surface runoff from the tunnel face is also presented. In October 2009, catastrophic failure resulted in a landslide, removing ~ 10 m-deep of bedrock from the entire ridge face directly above the tunnel entrance. Groundwater was collected from several drip sites in September 2009 and from the same drip sites in May, June, July and August 2010. The chemistry of the water dripping close to the tunnel entrance disrupted by the landslide implies that the post-landslide groundwater was from a meteoric source with negligible evapotranspiration demonstrating that the geomorphic perturbation allowed for the relatively rapid flushing of underlying bedrock fractures. The drop in [Cl-] of ~ 60 % was associated with a rise in the [SO42-] by a factor of ~ 4 and a positive shift in δ13C of the dissolved inorganic carbon (DIC) of ~ 12 ‰. This could imply that weathering products in the fresh post-landslide groundwater resulted from sulphuric acid weathering associated with a rise in the carbonate-derived DIC. The rise in the [SO42-] suggests that the landslide-induced exposure of fresh mineral surfaces resulted in the relatively rapid oxidation of pyrite, generating sulphuric acid, which then acted as the primary weathering agent. Given that [Ca2+] and [HCO3-] remained constant, secondary carbonate precipitation also took place and the rise in the [Na+] by a factor of >7 associated with a rise in [Mg2+] and [K+] suggest that silicate dissolution had also been enhanced by the oxidation of pyrite. These results imply that landslides provide a mechanism for weathering in the deep critical zone, which in this case constitutes a net output of CO2 to the atmosphere. Calmels, D., Galy, A., Hovius, N., Bickle, M., West, J.A., Chen, M-C., Chapman, H. Contribution of deep groundwater to the weathering budget in a rapidly eroding mountain belt, Taiwan. 2011. Earth and Planetary Science Letters 303: 48-58.

Estimation of urban runoff and water quality using remote sensing and artificial intelligence.

PubMed

Ha, S R; Park, S Y; Park, D H

2003-01-01

Water quality and quantity of runoff are strongly dependent on the landuse and landcover (LULC) criteria. In this study, we developed a more improved parameter estimation procedure for the environmental model using remote sensing (RS) and artificial intelligence (AI) techniques. Landsat TM multi-band (7bands) and Korea Multi-Purpose Satellite (KOMPSAT) panchromatic data were selected for input data processing. We employed two kinds of artificial intelligence techniques, RBF-NN (radial-basis-function neural network) and ANN (artificial neural network), to classify LULC of the study area. A bootstrap resampling method, a statistical technique, was employed to generate the confidence intervals and distribution of the unit load. SWMM was used to simulate the urban runoff and water quality and applied to the study watershed. The condition of urban flow and non-point contaminations was simulated with rainfall-runoff and measured water quality data. The estimated total runoff, peak time, and pollutant generation varied considerably according to the classification accuracy and percentile unit load applied. The proposed procedure would efficiently be applied to water quality and runoff simulation in a rapidly changing urban area.

[Characteristics of rainfall and runoff in urban drainage based on the SWMM model.

PubMed

Xiong, Li Jun; Huang, Fei; Xu, Zu Xin; Li, Huai Zheng; Gong, Ling Ling; Dong, Meng Ke

2016-11-18

The characteristics of 235 rainfall and surface runoff events, from 2009 to 2011 in a typical urban drainage area in Shanghai were analyzed by using SWMM model. The results showed that the rainfall events in the region with high occurrence frequency were characterized by small rainfall amount and low intensity. The most probably occurred rainfall had total amount less than 10 mm, or mean intensity less than 5 mm·h -1 ,or peak intensity less than 10 mm·h -1 , accounting for 66.4%, 88.8% and 79.6% of the total rainfall events, respectively. The study was of great significance to apply low-impact development to reduce runoff and non-point source pollution under condition of less rainfall amount or low mean rainfall intensity in the area. The runoff generally increased with the increase of rainfall. The threshold of regional occurring runoff was controlled by not only rainfall amount, but also mean rainfall intensity and rainfall duration. In general, there was no surface runoff when the rainfall amount was less than 2 mm. When the rainfall amount was between 2 to 4 mm and the mean rainfall intensity was below 1.6 mm·h -1 , the runoff was less than 1 mm. When the rainfall exceeded 4 mm and the mean rainfall intensity was larger than 1.6 mm·h -1 , the runoff would occur generally. Based on the results of the SWMM simulation, three regression equations that were applicable to regional runoff amount and rainfall factors were established. The adjustment R 2 of the three equations were greater than 0.97. This indicated that the equations could reflect well the relationship between runoff and rainfall variables. The results provided the basis of calculations to plan low impact development and better reduce overflow pollution in local drainage area. It also could serve as a useful reference for runoff study in similar drainage areas.

Estimation of the effects of land use and groundwater withdrawals on streamflow for the Pomperaug River, Connecticut

USGS Publications Warehouse

Bjerklie, David M.; Starn, J. Jeffrey; Tamayo, Claudia

2010-01-01

A precipitation runoff model for the Pomperaug River watershed, Connecticut was developed to address issues of concern including the effect of development on streamflow and groundwater recharge, and the implications of water withdrawals on streamflow. The model was parameterized using a strategy that requires a minimum of calibration and optimization by establishing basic relations between the parameter value and physical characteristics of individual hydrologic response units (HRUs) that comprise the model. The strategy was devised so that the information needed can be obtained from Geographic Information System and other general databases for Connecticut. Simulation of groundwater recharge enabled evaluation of the temporal and spatial mapping of recharge variation across the watershed and the spatial effects of changes in land cover on base flow and surface runoff. The modeling indicated that over the course of a year, groundwater provides between 60 and 70 percent of flow in the Pomperaug River; the remainder is generated by more rapid flow through the shallow subsurface and runoff from impermeable surfaces and saturated ground. Groundwater is recharged primarily during periods of low evapotranspiration in the winter, spring, and fall. The largest amount of recharge occurs in the spring in response to snowmelt. During floods, the Weekeepeemee and Nonnewaug Rivers (tributaries that form the Pomperaug River) respond rapidly with little flood peak attenuation due to flood-plain storage. In the Pomperaug River, flood-plain storage is more important in attenuating floods; abandoned quarry ponds (O&G ponds) adjacent to the river provide substantial flood storage above specific river stages when flow from the river spills over the banks and fills the ponds. Discharge from the ponds also helps to sustain low flows in the Pomperaug River. Similarly, releases from the Bronson-Lockwood reservoir sustain flow in the Nonnewaug River and tend to offset the effect of groundwater withdrawals from a well field adjacent to the river during periods of natural low flow. The model indicated that under the current zoning, future development could reduce low flows by as much as 10 percent at the 99 percent exceedance level (99 percent of flows are greater than or equal to this flow), but would not substantially increase the highest flows. Simulation of projected and hypothetical development in the watershed shows, depending on how stormwater is managed, that between 10 and 20 percent effective impervious area in an HRU results in streamflow becoming dominated by the surface-runoff component. This shift from a groundwater-dominated system would likely result in substantial changes in water quality and instream habitat characteristics of the river. Base flow to streams in the Pomperaug River watershed is reduced by both increased impervious surface and increased groundwater withdrawals. For the watershed as a whole, increasing groundwater withdrawals have the potential for causing greater overall reductions in flow compared to increased development and impervious surfaces. Additionally, on the basis of groundwater-modeling simulations, the projected increase in development across the watershed and, to a lesser extent the increase in groundwater withdrawals, will increase the number of local losing reaches experiencing dry conditions and the duration of these dry periods. The location of the losing reaches tends to be in areas near the transition from the uplands to the valley bottoms that are filled with coarse glacial stratified deposits. The simulated increase in the duration and extent of localized dry stream reaches is most sensitive to local increase in impervious surface. Conversion of land from forest or developed land cover to pasture or agricultural land increases groundwater recharge and discharge to streams, while at the same time increasing overall streamflow (the opposite effect as increased impervious surface). These resu

Applicability of GLDAS in the Yarlung Zangbo River Basin under Climate Change

NASA Astrophysics Data System (ADS)

Jia, L.; Hong, Z.; Linglei, Z.; Yun, D.

2017-12-01

The change of runoff has a great influence on global water cycle, and migration or transformation of biogenic matters. As the Tibet's most important economic region, the Yarlung Zangbo River basin is extremely sensitive and fragile to the global climate change. But the river is a typical lack-data basin, where the quantity of available runoff data is extremely limited and the spatial and temporal resolutions are very low. This study Chooses middle reaches of Yarlung Zangbo River basin as the study area, 4 models of Global Land Data Assimilation System (GLDAS) and the water balance equation are used to calculate surface runoff of Nuxia hydrological station from year of 2009 to 2013. Through the analysis of hydrological elements change, the impact of climate factors to surface runoff is discussed. At last, Statistical method is used to compare correlation and error between the 4 models results and in situ runoff observation. The Broke ranking method is applied to evaluate data quality and applicability of the 4 models in the Yarlung Zangbo River basin. The results reveal that the total runoff calculated from 4 models all have similar change cycle around 12 months, and the values all tend to have slight increase as in situ runoff data during research period. Moreover, it can conclude that the runoff time series show obvious period and mutation characters. During study period, monthly mean precipitation and temperature both have obvious seasonal variability, and the variation trend is relatively consistent. Through the analysis of the runoff affecting factors, it shows that the changes of precipitation and temperature are the most direct factors affecting runoff of the Yarlung Zangbo River. Correlation between precipitations, temperature with runoff of Nuxia hydrological station is good, and the correlation coefficients are in the range of 0.727 to 0.924.It shows that climate change controls basin runoff change to some extent. At last, runoff estimated from GLDAS-CLM can better represent runoff of the Yarlung Zangbo River basin than other 3 models with a total ranking score of 2.00. This paper carries out a helpful attempt on hydrological study in lack-data basin. And in the matter of medium and long terms, large and medium scales, the result is benefit to deepen cognition and comprehend on runoff characteristics.

Surface wastewater in Samara and their impact on water basins as water supply sources

NASA Astrophysics Data System (ADS)

Strelkov, Alexander; Shuvalov, Mikhail; Gridneva, Marina

2017-10-01

The paper gives an overview of surface wastewater outlets in Samara through the rainwater sewer system into the Saratov water reservoir and the Samara river. The rainwater sewer system in Samara is designed and executed according to a separate scheme, except for the old part of the city, where surface run-off is dumped into the sewer system through siphoned drain. The rainwater system disposes of surface, drainage, industrial clean-contamined waters, emergency and technology discharges from the city’s heat supply and water supply systems. The effluent discharge is carried out by means of separate wastewater outlets into ravines or directly into the Samara river and the Saratov water reservoir without cleaning. The effluent discharge is carried out through the rainwater sewer system with 17 wastewater outlets into the Saratov water reservoir. In the Samara river, surface runoff drainage and clean-contamined water of industrial enterprises is carried out through 14 wastewater outlets. This study emphasizes the demand to arrange effluent discharge and construction of sewage treatment plants to prevent contamination of water objects by surface run-off from residential areas and industrial territories.

Fluometuron and pendimethalin runoff from strip and conventionally tilled cotton in the southern atlantic coastal plain.

PubMed

Potter, Thomas L; Truman, Clint C; Bosch, David D; Bednarz, Craig

2004-01-01

In the Atlantic Coastal Plain region of southern Georgia (USA), cotton (Gossypium hirsutum L.) acreage increased threefold in the past decade. To more effectively protect water quality in the region, best management practices are needed that reduce pesticide runoff from fields in cotton production. This study compared runoff of two herbicides, fluometuron [N,N-dimethyl-N'-[3-(trifluoromethyl)-phenyl]-urea] and pendimethalin [N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitro-benzenamine], from plots in strip-tillage (ST) and conventional-tillage (CT) management near Tifton, GA. Rainfall simulations were conducted one day after preemergence herbicide applications to 0.0006-ha plots and runoff from 0.15-ha plots due to natural rainfall following preemergence pendimethalin and fluometuron and postemergence fluometuron use was monitored. Pendimethalin runoff was greater under CT than ST due to strong pendimethalin soil sorption and higher erosion and runoff under CT. The highest losses, 1.3% of applied in CT and 0.22% of applied in ST, were observed during rainfall simulations conducted 1 DAT. Fluometuron runoff from natural rainfall was substantially lower from ST than from CT plots but the trend was reversed in rainfall simulations. In all studies, fluometuron runoff was also relatively low (<1% of applied), and on plots under natural rainfall, desmethylfluometuron (DMF) represented about 50% of total fluometuron runoff. Fluometuron's relatively low runoff rate appeared linked to its rapid leaching, and high DMF detection rates in runoff support DMF inclusion in fluometuron risk assessments. Results showed that ST has the potential to reduce runoff of both herbicides, but fluometuron leaching may be a ground water quality concern.

Evaluation of Surface Runoff Generation Processes Using a Rainfall Simulator: A Small Scale Laboratory Experiment

NASA Astrophysics Data System (ADS)

Danáčová, Michaela; Valent, Peter; Výleta, Roman

2017-12-01

Nowadays, rainfall simulators are being used by many researchers in field or laboratory experiments. The main objective of most of these experiments is to better understand the underlying runoff generation processes, and to use the results in the process of calibration and validation of hydrological models. Many research groups have assembled their own rainfall simulators, which comply with their understanding of rainfall processes, and the requirements of their experiments. Most often, the existing rainfall simulators differ mainly in the size of the irrigated area, and the way they generate rain drops. They can be characterized by the accuracy, with which they produce a rainfall of a given intensity, the size of the irrigated area, and the rain drop generating mechanism. Rainfall simulation experiments can provide valuable information about the genesis of surface runoff, infiltration of water into soil and rainfall erodibility. Apart from the impact of physical properties of soil, its moisture and compaction on the generation of surface runoff and the amount of eroded particles, some studies also investigate the impact of vegetation cover of the whole area of interest. In this study, the rainfall simulator was used to simulate the impact of the slope gradient of the irrigated area on the amount of generated runoff and sediment yield. In order to eliminate the impact of external factors and to improve the reproducibility of the initial conditions, the experiments were conducted in laboratory conditions. The laboratory experiments were carried out using a commercial rainfall simulator, which was connected to an external peristaltic pump. The pump maintained a constant and adjustable inflow of water, which enabled to overcome the maximum volume of simulated precipitation of 2.3 l, given by the construction of the rainfall simulator, while maintaining constant characteristics of the simulated precipitation. In this study a 12-minute rainfall with a constant intensity of 5 mm/min was used to irrigate a corrupted soil sample. The experiment was undertaken for several different slopes, under the condition of no vegetation cover. The results of the rainfall simulation experiment complied with the expectations of a strong relationship between the slope gradient, and the amount of surface runoff generated. The experiments with higher slope gradients were characterised by larger volumes of surface runoff generated, and by shorter times after which it occurred. The experiments with rainfall simulators in both laboratory and field conditions play an important role in better understanding of runoff generation processes. The results of such small scale experiments could be used to estimate some of the parameters of complex hydrological models, which are used to model rainfall-runoff and erosion processes at catchment scale.

Nitrate-nitrogen reduction by established tree and pasture buffer strips associated with a cattle feedlot effluent disposal area near Armidale, NSW Australia.

PubMed

Wang, Liangmin; Duggin, John A; Nie, Daoping

2012-05-30

Vegetated buffer strips have been recognized as an important element in overall agro-ecosystem management to reduce the delivery of non-point source pollutants from agricultural land to inland water systems. A buffer strip experiment consisting of two tree species (Eucalyptus camaldulensis and Casuarina cunninghamiana) with two planting densities and a pasture treatment was conducted to determine the effectiveness of NO(3)-N removal from a cattle feedlot effluent disposal area at Tullimba near Armidale, NSW Australia. Different management methods were applied for the buffers where grass and weeds were mowed 2-3 times during the second and third years and were not managed during the rest experimental years for the tree buffer, while grass was harvested 1-3 times per year for the pasture buffer. The differences between tree species and planting density significantly affected tree growth, but the growth difference did not significantly affect their capacities to reduce NO(3)-N in soil surface runoff and groundwater. On average for all the tree and pasture treatments, the buffer strips reduced NO(3)-N concentration by 8.5%, 14.7% and 14.4% for the surface runoff, shallow and deep groundwater respectively. The tree and pasture buffer strips were not significantly different in NO(3)-N reduction for both shallow and deep groundwater while the pasture buffer strips reduced significantly more NO(3)-N concentration in surface runoff than the tree buffer strips. Both buffer strips reduced more than 50% of surface runoff volume indicating that both the tree and pasture buffer strips were efficient at removing water and nutrients, mostly through a significant reduction in soil surface runoff volume. Copyright © 2012 Elsevier Ltd. All rights reserved.

EVALUATION OF ECONOMIC INCENTIVES FOR DECENTRALIZED STORMWATER RUNOFF MANAGEMENT

EPA Science Inventory

Impervious surfaces in urban and suburban areas can lead to excess stormwater runoff throughout a watershed, typically resulting in widespread hydrologic and ecological alteration of receiving streams. Decentralized stormwater management may improve stream ecosystems by reducing ...

Hillslope run-off thresholds with shrink–swell clay soils

USGS Publications Warehouse

Stewart, Ryan D.; Abou Najm, Majdi R.; Rupp, David E.; Lane, John W.; Uribe, Hamil C.; Arumí, José Luis; Selker, John S.

2015-01-01

Irrigation experiments on 12 instrumented field plots were used to assess the impact of dynamic soil crack networks on infiltration and run-off. During applications of intensity similar to a heavy rainstorm, water was seen being preferentially delivered within the soil profile. However, run-off was not observed until soil water content of the profile reached field capacity, and the apertures of surface-connected cracks had closed >60%. Electrical resistivity measurements suggested that subsurface cracks persisted and enhanced lateral transport, even in wet conditions. Likewise, single-ring infiltration measurements taken before and after irrigation indicated that infiltration remained an important component of the water budget at high soil water content values, despite apparent surface sealing. Overall, although the wetting and sealing of the soil profile showed considerable complexity, an emergent property at the hillslope scale was observed: all of the plots demonstrated a strikingly similar threshold run-off response to the cumulative precipitation amount. 

Broiler Litter × Industrial By-Products Reduce Nutrients and Microbial Losses in Surface Runoff When Applied to Forages.

PubMed

Adeli, Ardeshir; Read, John J; Brooks, John P; Miles, Dana; Feng, Gary; Jenkins, Johnie N

2017-03-01

The inability to incorporate broiler litter (BL) into permanent hayfields and pastures leads to nutrient accumulation near the soil surface and increases the potential transport of nutrients in runoff. This study was conducted on Marietta silt loam soil to determine the effect of flue gas desulfurization (FGD) gypsum and lignite on P, N, C, and microbial concentrations in runoff. Treatments were (i) control (unfertilized) and (ii) BL at 13.4 Mg ha alone or (iii) treated with either FGD gypsum or lignite applied at 20% (w/w) (2.68 Mg ha). Rainfall simulators were used to produce a 5.6 cm h storm event sufficient in duration to cause 15 min of continuous runoff. Repeated rains were applied at 3-d intervals to determine how long FGD gypsum and lignite are effective in reducing loss of litter-derived N, P, and C from soil. Application of BL increased N, P, and C concentrations in runoff as compared to the control. Addition of FGD gypsum reduced ( < 0.05) water-soluble P and dissolved organic C concentrations in runoff by 39 and 16%, respectively, as compared to BL alone. Lignite reduced runoff total N and NH-N concentrations by 38 and 70%, respectively, as compared to BL alone. Addition of FGD gypsum or lignite failed to significantly reduce microbial loads in runoff, although both treatments reduced microbial concentration by >20%. Thus, BL treated with FGD and lignite can be considered as cost-effective management practices in the mitigation of P, N, and C and possibly microbial concentration in runoff. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Oceanographic gradients and seabird prey community dynamics in glacial fjords

USGS Publications Warehouse

Arimitsu, Mayumi L.; Piatt, John F.; Madison, Erica N.; Conaway, Jeffrey S.; Hillgruber, N.

2012-01-01

Glacial fjord habitats are undergoing rapid change as a result of contemporary global warming, yet little is known about how glaciers influence marine ecosystems. These ecosystems provide important feeding, breeding and rearing grounds for a wide variety of marine organisms, including seabirds of management concern. To characterize ocean conditions and marine food webs near tidewater glaciers, we conducted monthly surveys of oceanographic variables, plankton, fish and seabirds in Kenai Fjords, Alaska, from June to August of 2007 and 2008. We also measured tidal current velocities near glacial features. We found high sediment load from glacial river runoff played a major role in structuring the fjord marine ecosystem. Submerged moraines (sills) isolated cool, fresh, stratified and silt-laden inner fjord habitats from oceanic influence. Near tidewater glaciers, surface layers of turbid glacial runoff limited availability of light to phytoplankton, but macrozooplankton were abundant in surface waters, perhaps due to the absence of a photic cue for diel migration. Fish and zooplankton community structure varied along an increasing temperature gradient throughout the summer. Acoustic measurements indicated that low density patches of fish and zooplankton were available in the surface waters near glacial river outflows. This is the foraging habitat occupied most by Kittlitz's murrelet (Brachyramphus brevirostris), a rare seabird that appears to be specialized for life in glacially influenced environments. Kittlitz's murrelets were associated with floating glacial ice, and they were more likely to occur near glaciers, in deeper water, and in areas with high acoustic backscatter. Kittlitz's murrelet at-sea distribution was limited to areas influenced by turbid glacial outflows, and where prey was concentrated near the surface in waters with low light penetration. Tidewater glaciers impart unique hydrographic characteristics that influence marine plankton and fish communities, and this has cascading effects on marine food webs in these ecosystems.

Evaluating runoff simulations from the Community Land Model 4.0 using observations from flux towers and a mountainous watershed

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Hongyi; Huang, Maoyi; Wigmosta, Mark S.

2011-12-24

Previous studies using the Community Land Model (CLM) focused on simulating landatmosphere interactions and water balance at continental to global scales, with limited attention paid to its capability for hydrologic simulations at watershed or regional scales. This study evaluates the performance of CLM 4.0 (CLM4) for hydrologic simulations, and explores possible directions of improvement. Specifically, it is found that CLM4 tends to produce unrealistically large temporal variation of runoff for applications at a mountainous catchment in the Northwest United States where subsurface runoff is dominant, as well as at a few flux tower sites. We show that runoff simulations frommore » CLM4 can be improved by: (1) increasing spatial resolution of the land surface representations; (2) calibrating parameter values; (3) replacing the subsurface formulation with a more general nonlinear function; (4) implementing the runoff generation schemes from the Variability Infiltration Capacity (VIC) model. This study also highlights the importance of evaluating both the energy and water fluxes application of land surface models across multiple scales.« less

Effects of soil type on leaching and runoff transport of rare earth elements and phosphorous in laboratory experiments.

PubMed

Wang, Lingqing; Liang, Tao; Chong, Zhongyi; Zhang, Chaosheng

2011-01-01

Through leaching experiments and simulated rainfall experiments, characteristics of vertical leaching of exogenous rare earth elements (REEs) and phosphorus (P) and their losses with surface runoff during simulated rainfall in different types of soils (terra nera soil, cinnamon soil, red soil, loess soil, and purple soil) were investigated. Results of the leaching experiments showed that vertical transports of REEs and P were relatively low, with transport depths less than 6 cm. The vertical leaching rates of REEs and P in the different soils followed the order of purple soil > terra nera soil > red soil > cinnamon soil > loess soil. Results of the simulated rainfall experiments (83 mm h⁻¹) revealed that more than 92% of REEs and P transported with soil particles in runoff. The loss rates of REEs and P in surface runoff in the different soil types were in the order of loess soil > terra nera soil > cinnamon soil > red soil > purple soil. The total amounts of losses of REEs and P in runoff were significantly correlated.

The Continuing Evolution of Land Surface Parameterizations

NASA Technical Reports Server (NTRS)

Koster, Randal; Houser, Paul (Technical Monitor)

2001-01-01

Land surface models (LSMs) play a critical role in the simulation of climate, for they determine the character of a large fraction of the atmosphere's lower boundary. The LSM partitions the net radiative energy at the land surface into sensible heat, latent heat, and energy storage, and it partitions incident precipitation water into evaporation, runoff, and water storage. Numerous modeling experiments and the existing (though very scant) observational evidence suggest that variations in these partitionings can feed back on the atmospheric processes that induce them. This land-atmosphere feedback can in turn have a significant impact on the generation of continental precipitation. For this and other reasons (including the role of the land surface in converting various atmospheric quantities, such as precipitation, into quantities of perhaps higher societal relevance, such as runoff), many modeling groups are placing a high emphasis on improving the treatment of land surface processes in their models. LSMs have evolved substantially from the original bucket model of Manabe et al. This evolution, which is still ongoing, has been documented considerably. The present paper also takes a look at the evolution of LSMs. The perspective here, though, is different - the evolution is considered strictly in terms of the 'balance' between the formulations of evaporation and runoff processes. The paper will argue that a proper balance is currently missing, largely due to difficulties in treating subgrid variability in soil moisture and its impact on the generation of runoff.

Discharge-nitrate data clustering for characterizing surface-subsurface flow interaction and calibration of a hydrologic model

NASA Astrophysics Data System (ADS)

Shrestha, R. R.; Rode, M.

2008-12-01

Concentration of reactive chemicals has different chemical signatures in baseflow and surface runoff. Previous studies on nitrate export from a catchment indicate that the transport processes are driven by subsurface flow. Therefore nitrate signature can be used for understanding the event and pre-event contributions to streamflow and surface-subsurface flow interactions. The study uses flow and nitrate concentration time series data for understanding the relationship between these two variables. Unsupervised artificial neural network based learning method called self organizing map is used for the identification of clusters in the datasets. Based on the cluster results, five different pattern in the datasets are identified which correspond to (i) baseflow, (ii) subsurface flow increase, (iii) surface runoff increase, (iv) surface runoff recession, and (v) subsurface flow decrease regions. The cluster results in combination with a hydrologic model are used for discharge separation. For this purpose, a multi-objective optimization tool NSGA-II is used, where violation of cluster results is used as one of the objective functions. The results show that the use of cluster results as supplementary information for the calibration of a hydrologic model gives a plausible simulation of subsurface flow as well total runoff at the catchment outlet. The study is undertaken using data from the Weida catchment in the North-Eastern Germany, which is a sub-catchment of the Weisse Elster river in the Elbe river basin.

Upscaling Empirically Based Conceptualisations to Model Tropical Dominant Hydrological Processes for Historical Land Use Change

NASA Astrophysics Data System (ADS)

Toohey, R.; Boll, J.; Brooks, E.; Jones, J.

2009-12-01

Surface runoff and percolation to ground water are two hydrological processes of concern to the Atlantic slope of Costa Rica because of their impacts on flooding and drinking water contamination. As per legislation, the Costa Rican Government funds land use management from the farm to the regional scale to improve or conserve hydrological ecosystem services. In this study, we examined how land use (e.g., forest, coffee, sugar cane, and pasture) affects hydrological response at the point, plot (1 m2), and the field scale (1-6ha) to empirically conceptualize the dominant hydrological processes in each land use. Using our field data, we upscaled these conceptual processes into a physically-based distributed hydrological model at the field, watershed (130 km2), and regional (1500 km2) scales. At the point and plot scales, the presence of macropores and large roots promoted greater vertical percolation and subsurface connectivity in the forest and coffee field sites. The lack of macropores and large roots, plus the addition of management artifacts (e.g., surface compaction and a plough layer), altered the dominant hydrological processes by increasing lateral flow and surface runoff in the pasture and sugar cane field sites. Macropores and topography were major influences on runoff generation at the field scale. Also at the field scale, antecedent moisture conditions suggest a threshold behavior as a temporal control on surface runoff generation. However, in this tropical climate with very intense rainstorms, annual surface runoff was less than 10% of annual precipitation at the field scale. Significant differences in soil and hydrological characteristics observed at the point and plot scales appear to have less significance when upscaled to the field scale. At the point and plot scales, percolation acted as the dominant hydrological process in this tropical environment. However, at the field scale for sugar cane and pasture sites, saturation-excess runoff increased as irrigation intensity and duration (e.g., quantity) increased. Upscaling our conceptual models to the watershed and regional scales, historical data (1970-2004) was used to investigate whether dominant hydrological processes changed over time due to land use change. Preliminary investigations reveal much higher runoff coefficients (<30%) at the larger watershed scales. The increase in importance of runoff at the larger geographic scales suggests an emerging process and process non-linearity between the smaller and larger scales. Upscaling is an important and useful concept when investigating catchment response using the tools of field work and/or physically distributed hydrological modeling.

Development of a human-specific B. thetaiotaomicron IMS ...

EPA Pesticide Factsheets

Immunomagnetic separation/adenosine triphosphate (IMS/ATP) assays utilize paramagnetic beads and target-specific antibodies to isolate target organisms. Following isolation, adenosine tri-phosphate (ATP) is extracted from the target population and quantified. An inversely-coupled (Inv-IMS/ATP)assay for detection of Bacteroides thetaiotaomicron was developed and applied for rapid detection of human-associated fecal contamination in surface waters in Baja California. Specificity of the assay was tested against challenge solutions of varying concentrations of dog, gull, horse and chicken feces, and a field validation survey of coastal and WWTP effluent water quality in Rosarito and Enseneda, Baja California was conducted. Inv IMS/ATP measurements made shown to be specific and sensitive to human fecal contamination. At test concentrations of less than 1000 MPN ENT/100 mL, sensitivity and specificity of the assay both exceeded 80%. Moreover, the Inv-IMS/ATP assay yielded measurements of viable B. thetaiotaomicron that were comparable to the HF183 human marker in complex surface waters impacted with both wastewater and runoff, and the Inv-IMS/ATP assay was able to effectively differentiate between surface waters impacted with adequately and inadequately treated wastewater. The Inv-IMS/ATP assays shows promise for rapid evaluation of recreational water quality in areas where access to more expensive methods is limited and in areas where water quality in unpredicta

Frequency analysis of urban runoff quality in an urbanizing catchment of Shenzhen, China

NASA Astrophysics Data System (ADS)

Qin, Huapeng; Tan, Xiaolong; Fu, Guangtao; Zhang, Yingying; Huang, Yuefei

2013-07-01

This paper investigates the frequency distribution of urban runoff quality indicators using a long-term continuous simulation approach and evaluates the impacts of proposed runoff control schemes on runoff quality in an urbanizing catchment in Shenzhen, China. Four different indicators are considered to provide a comprehensive assessment of the potential impacts: total runoff depth, event pollutant load, Event Mean Concentration, and peak concentration during a rainfall event. The results obtained indicate that urban runoff quantity and quality in the catchment have significant variations in rainfall events and a very high rate of non-compliance with surface water quality regulations. Three runoff control schemes with the capacity to intercept an initial runoff depth of 5 mm, 10 mm, and 15 mm are evaluated, respectively, and diminishing marginal benefits are found with increasing interception levels in terms of water quality improvement. The effects of seasonal variation in rainfall events are investigated to provide a better understanding of the performance of the runoff control schemes. The pre-flood season has higher risk of poor water quality than other seasons after runoff control. This study demonstrates that frequency analysis of urban runoff quantity and quality provides a probabilistic evaluation of pollution control measures, and thus helps frame a risk-based decision making for urban runoff quality management in an urbanizing catchment.

High-resolution modeling of coastal freshwater discharge and glacier mass balance in the Gulf of Alaska watershed

NASA Astrophysics Data System (ADS)

Beamer, J. P.; Hill, D. F.; Arendt, A.; Liston, G. E.

2016-05-01

A comprehensive study of the Gulf of Alaska (GOA) drainage basin was carried out to improve understanding of the coastal freshwater discharge (FWD) and glacier volume loss (GVL). Hydrologic processes during the period 1980-2014 were modeled using a suite of physically based, spatially distributed weather, energy-balance snow/ice melt, soil water balance, and runoff routing models at a high-resolution (1 km horizontal grid; daily time step). Meteorological forcing was provided by the North American Regional Reanalysis (NARR), Modern Era Retrospective Analysis for Research and Applications (MERRA), and Climate Forecast System Reanalysis (CFSR) data sets. Streamflow and glacier mass balance modeled using MERRA and CFSR compared well with observations in four watersheds used for calibration in the study domain. However, only CFSR produced regional seasonal and long-term trends in water balance that compared favorably with independent Gravity Recovery and Climate Experiment (GRACE) and airborne altimetry data. Mean annual runoff using CFSR was 760 km3 yr-1, 8% of which was derived from the long-term removal of stored water from glaciers (glacier volume loss). The annual runoff from CFSR was partitioned into 63% snowmelt, 17% glacier ice melt, and 20% rainfall. Glacier runoff, taken as the sum of rainfall, snow, and ice melt occurring each season on glacier surfaces, was 38% of the total seasonal runoff, with the remaining runoff sourced from nonglacier surfaces. Our simulations suggests that existing GRACE solutions, previously reported to represent glacier mass balance alone, are actually measuring the full water budget of land and ice surfaces.

Impervious surfaces and sewer pipe effects on stormwater runoff temperature

NASA Astrophysics Data System (ADS)

Sabouri, F.; Gharabaghi, B.; Mahboubi, A. A.; McBean, E. A.

2013-10-01

The warming effect of the impervious surfaces in urban catchment areas and the cooling effect of underground storm sewer pipes on stormwater runoff temperature are assessed. Four urban residential catchment areas in the Cities of Guelph and Kitchener, Ontario, Canada were evaluated using a combination of runoff monitoring and modelling. The stormwater level and water temperature were monitored at 10 min interval at the inlet of the stormwater management ponds for three summers 2009, 2010 and 2011. The warming effect of the ponds is also studied, however discussed in detail in a separate paper. An artificial neural network (ANN) model for stormwater temperature was trained and validated using monitoring data. Stormwater runoff temperature was most sensitive to event mean temperature of the rainfall (EMTR) with a normalized sensitivity coefficient (Sn) of 1.257. Subsequent levels of sensitivity corresponded to the longest sewer pipe length (LPL), maximum rainfall intensity (MI), percent impervious cover (IMP), rainfall depth (R), initial asphalt temperature (AspT), pipe network density (PND), and rainfall duration (D), respectively. Percent impervious cover of the catchment area (IMP) was the key parameter that represented the warming effect of the paved surfaces; sensitivity analysis showed IMP increase from 20% to 50% resulted in runoff temperature increase by 3 °C. The longest storm sewer pipe length (LPL) and the storm sewer pipe network density (PND) are the two key parameters that control the cooling effect of the underground sewer system; sensitivity analysis showed LPL increase from 345 to 966 m, resulted in runoff temperature drop by 2.5 °C.

Quantifying components of the hydrologic cycle in Virginia using chemical hydrograph separation and multiple regression analysis

USGS Publications Warehouse

Sanford, Ward E.; Nelms, David L.; Pope, Jason P.; Selnick, David L.

2012-01-01

This study by the U.S. Geological Survey, prepared in cooperation with the Virginia Department of Environmental Quality, quantifies the components of the hydrologic cycle across the Commonwealth of Virginia. Long-term, mean fluxes were calculated for precipitation, surface runoff, infiltration, total evapotranspiration (ET), riparian ET, recharge, base flow (or groundwater discharge) and net total outflow. Fluxes of these components were first estimated on a number of real-time-gaged watersheds across Virginia. Specific conductance was used to distinguish and separate surface runoff from base flow. Specific-conductance data were collected every 15 minutes at 75 real-time gages for approximately 18 months between March 2007 and August 2008. Precipitation was estimated for 1971–2000 using PRISM climate data. Precipitation and temperature from the PRISM data were used to develop a regression-based relation to estimate total ET. The proportion of watershed precipitation that becomes surface runoff was related to physiographic province and rock type in a runoff regression equation. Component flux estimates from the watersheds were transferred to flux estimates for counties and independent cities using the ET and runoff regression equations. Only 48 of the 75 watersheds yielded sufficient data, and data from these 48 were used in the final runoff regression equation. The base-flow proportion for the 48 watersheds averaged 72 percent using specific conductance, a value that was substantially higher than the 61 percent average calculated using a graphical-separation technique (the USGS program PART). Final results for the study are presented as component flux estimates for all counties and independent cities in Virginia.

Response of turf and quality of water runoff to manure and fertilizer.

PubMed

Gaudreau, J E; Vietor, D M; White, R H; Provin, T L; Munster, C L

2002-01-01

Manure applications can benefit turfgrass production and unused nutrients in manure residues can be exported through sod harvests. Yet, nutrients near the soil surface could be transported in surface runoff. Our research objective was to evaluate responses of bermudagrass [Cynodon dactylon (L.) Pers. var. Guymon] turf and volumes and P and N concentrations of surface runoff after fertilizer or composted manure applications. Three replications of five treatments were established on a Boonville fine sandy loam (fine, smectitic, thermic Vertic Albaqualf) that was excavated to create an 8.5% slope. Manure rates of 50 and 100 kg P ha(-1) at the start of two monitoring periods were compared with P fertilizer rates of 25 and 50 kg ha(-1) and an unfertilized control. Compared with initial soil tests, nitrate concentrations decreased and P concentrations increased after two manure or fertilizer applications and eight rain events over the two monitoring periods. The fertilizer sources of P and N produced 19% more dry weight and 21% larger N concentrations in grass clippings than manure sources. Yet, runoff volumes were similar between manure and fertilizer sources of P. Dissolved P concentration (30 mg L(-1)) in runoff during a rain event 3 d after application of 50 kg P ha(-1) was five times greater for fertilizer than for manure P. Observations during both monitoring periods indicated that total P and N losses in runoff were no greater for composted manure than for fertilizer sources of P at relatively large P rates on a steep slope of turfgrass.

Limited Dissolved Phosphorus Runoff Losses from Layered Double Hydroxide and Struvite Fertilizers in a Rainfall Simulation Study.

PubMed

Everaert, Maarten; da Silva, Rodrigo C; Degryse, Fien; McLaughlin, Mike J; Smolders, Erik

2018-03-01

The enrichment of P in surface waters has been linked to P runoff from agricultural fields amended with fertilizers. Novel slow-release mineral fertilizers, such as struvite and P-exchanged layered double hydroxides (LDHs), have received increasing attention for P recycling from waste streams, and these fertilizers may potentially reduce the risk of runoff losses. Here, a rainfall simulation experiment was performed to evaluate P runoff associated with the application of recycled slow-release fertilizers relative to that of a soluble fertilizer. Monoammonium phosphate (MAP), struvite, and LDH granular fertilizers were broadcasted at equal total P doses on soil packed in trays (5% slope) and covered with perennial ryegrass ( L.). Four rainfall simulation events of 30 min were performed at 1, 5, 15, and 30 d after the fertilizer application. Runoff water from the trays was collected, filtered, and analyzed for dissolved P. For the MAP treatment, P runoff losses were high in the first two rain events and leveled off in later rain events. In total, 42% of the applied P in the MAP treatment was lost due to runoff. In the slow-release fertilizer treatments, P runoff losses were limited to 1.9 (struvite) and 2.4% (LDH) of the applied doses and were more similar over the different rain events. The use of these novel P fertilizer forms could be beneficial in areas with a high risk of surface water eutrophication and a history of intensive fertilization. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Urban runoff (URO) process for MODFLOW 2005: simulation of sub-grid scale urban hydrologic processes in Broward County, FL

USGS Publications Warehouse

Decker, Jeremy D.; Hughes, J.D.

2013-01-01

Climate change and sea-level rise could cause substantial changes in urban runoff and flooding in low-lying coast landscapes. A major challenge for local government officials and decision makers is to translate the potential global effects of climate change into actionable and cost-effective adaptation and mitigation strategies at county and municipal scales. A MODFLOW process is used to represent sub-grid scale hydrology in urban settings to help address these issues. Coupled interception, surface water, depression, and unsaturated zone storage are represented. A two-dimensional diffusive wave approximation is used to represent overland flow. Three different options for representing infiltration and recharge are presented. Additional features include structure, barrier, and culvert flow between adjacent cells, specified stage boundaries, critical flow boundaries, source/sink surface-water terms, and the bi-directional runoff to MODFLOW Surface-Water Routing process. Some abilities of the Urban RunOff (URO) process are demonstrated with a synthetic problem using four land uses and varying cell coverages. Precipitation from a hypothetical storm was applied and cell by cell surface-water depth, groundwater level, infiltration rate, and groundwater recharge rate are shown. Results indicate the URO process has the ability to produce time-varying, water-content dependent infiltration and leakage, and successfully interacts with MODFLOW.

Estimation of Surface Runoff in the Jucar River Basin from Rainfall Data and SMOS Soil Moisture

NASA Astrophysics Data System (ADS)

Garcia Leal, Julio A.; Estrela, Teodoro; Fidalgo, Arancha; Gabaldo, Onofre; Gonzalez Robles, Maura; Herrera Daza, Eddy; Khodayar, Samiro; Lopez-Baeza, Ernesto

2013-04-01

Surface runoff is the water that flows after soil is infiltrated to full capacity and excess water from rain, meltwater, or other sources flows over the land. When the soil is saturated and the depression storage filled, and rain continues to fall, the rainfall will immediately produce surface runoff. The Soil Conservation Service Curve Number (SCS-CN) method is widely used for determining the approximate direct runoff volume for a given rainfall event in a particular area. The advantage of the method is its simplicity and widespread inclusion in existing computer models. It was originally developed by the US Department of Agriculture, Soil Conservation Service, and documented in detail in the National Engineering Handbook, Sect. 4: Hydrology (NEH-4) (USDA-SCS, 1985). Although the SCS-CN method was originally developed in the United States and mainly for the evaluation of storm runoff in small agricultural watersheds, it soon evolved well beyond its original objective and was adopted for various land uses and became an integral part of more complex, long-term, simulation models. The basic assumption of the SCS-CN method is that, for a single storm, the ratio of actual soil retention after runoff begins to potential maximum retention is equal to the ratio of direct runoff to available rainfall. This relationship, after algebraic manipulation and inclusion of simplifying assumptions, results in the following equation given in USDA-SCS (1985): (P--0,2S)2 Q = (P + 0,8S) where Q is the average runoff (mm), P the effective precipitation (mm) and S is potential maximum retention (mm) after the rainfall event. The study has been applied to the Jucar River Basin area, East of Spain. A selection of recent significant rainfall events has been made corresponding to the periods around 22nd November, 2011 and 28-29 September and 10 October, 2012, from Jucar River Basin Authority rain gauge data. Potential maximum retention values for each point have been assumed as the first SMOS soil moisture values available at the closest DGG node immediately after saturation produced by the rain. The results are shown as maps of precipitation and soil moisture obtained using a V4 integration method between a linear and nearest neighbour methods. Surface runoff maps are consequently obtained using the SCS-CN equation given earlier. These results have also been compared to COSMO-CLM model simulations for the same periods. It is envisaged to obtain precipitation maps from MSG-SEVIRI data.

REMOVAL OF DISSOLVED POLLUTANTS FROM URBAN STORMWATER RUNOFF

EPA Science Inventory

Stormwater runoff, because of its heavy metals and poly aromatic hydrocarbons (PAHs) content, may be considered toxic for discharge to receiving surface waters without further treatment. A number of structural devices, collectively known as structural best management practices (...

Effect of age and rainfall pH on contaminant yields from metal roofs.

PubMed

Wicke, Daniel; Cochrane, Thomas A; O'Sullivan, Aisling D; Cave, Simon; Derksen, Mark

2014-01-01

Metal roofs are recognized for conveying significant metal loads to urban streams through stormwater runoff. Metal concentrations in urban runoff depend on roof types and prevailing weather conditions but the combined effects of roof age and rainfall pH on metal mobilization are not well understood. To investigate these effects on roof runoff, water quality was analysed from galvanized iron and copper roofs following rainfall events and also from simulating runoff using a rainfall simulator on specially constructed roof modules. Zinc and copper yields under different pH regimes were investigated for two roof materials and two different ages. Metal mobilization from older roofs was greater than new roofs with 55-year-old galvanized roof surfaces yielding more Zn, on average increasing by 45% and 30% under a rainfall pH of 4 and 8, respectively. Predominantly dissolved (85-95%) Zn and Cu concentrations in runoff exponentially increased as the rainfall pH decreased. Results also confirmed that copper guttering and downpipes associated with galvanized steel roof systems can substantially increase copper levels in roof runoff. Understanding the dynamics of roof surfaces as a function of weathering and rainfall pH regimes can help developers with making better choices about roof types and materials for stormwater improvement.

Increasing freshwater runoff and tidal action influences on spatial mixing patterns in Søndre Strømfjord, West Greenland.

NASA Astrophysics Data System (ADS)

Smiley, Crystal; Kamenos, Nick; Hoey, Trevor; Cottier, Finlo; Ellam, Rob

2015-04-01

Greenland Ice Sheet melt has the potential to affect global sea levels and the strength of the thermohaline circulation (THC). Investigating spatial mixing patterns of seawater in Greenlandic fjords can help reveal characteristics of changes in runoff from the GrIS; for example higher runoff may be associated with lower salinity within GrIS fjords, which can be recorded by palaeoenvironmental proxies (Kamenos et al 2012). The Kangerlussuaq Drainage Basin mirrors melt patterns of the whole GrIS and drains into Søndre Strømfjord, a 170km long fjord on the west coast of Greenland. Temperature and salinity profiles to 40m depth were obtained at 11 stations along Søndre Strømfjord during the 2014 melt season. Each station was sampled twice once at high KDB runoff and once at low KDB runoff. With increasing freshwater runoff, salinity decreased by 1.65 - 2.91 and temperature increased by 0.47oC- 2.34oC at each station over a 7 hour time period. Higher salinities occurred at low run-off. In addition, with increasing run-off, the disparity between surface and deeper water (30m) salinity became greater with a 19.3 difference between the surface and 30m. This information was integrated with oxygen and deuterium isotopic signatures collected at 10 m depth from each station to pinpoint the exact source of the runoff causing salinity reductions. With increasing freshwater runoff, the chemistry of the fjord exhibits an enrichment of the heavier isotope. δ18Ovsmow values enrich by 7.40 permil while δDvsmow enrich 53.26 permil. Our data shows a relationship between KDB runoff, salinity, and oxygen, hydrogen isotopic chemistry of Søndre Strømfjord, data that will enable further calibration of marine proxies of GrIS melt. References Kamenos, N.A, Hoey, T.B, Nienow, P., Fallick, A.E., & Claverie, T., 2012: Reconstructing Greenland Ice Sheet runoff using coralline algae; Geological Society of America, Geology, doi: 10.1130/G33405.1

Hydrochemical controls on reservoir nutrient and phytoplankton dynamics under storms.

PubMed

Chen, Nengwang; Mo, Qiongli; Kuo, Yi-Ming; Su, Yuping; Zhong, Yanping

2018-04-01

Eutrophication and undesired algal blooms in surface water are common and have been linked to increasing nutrient loading. Effects of extreme events such as storms on reservoir nutrient and phytoplankton remain unclear. Here we carried out continuous high-frequency measurements in a long and narrow dam reservoir in southeast China during a storm period in June-July 2015. Our results show a strong nutrient-phytoplankton relationship as well as a very rapid response to storm runoff. We observed an increase in total suspended matter (TSM), ammonium (NH 4 -N), and dissolved reactive phosphate (DRP), with a sharp decline in chlorophyll-a (Chl-a) in the high flow periods. Afterward, Chl-a, total phytoplankton abundance and Cyanophyta fraction elevated gradually. Nitrate was diluted at first with increasing discharge before concentration increased, likely following a delayed input of groundwater. Physiochemical parameters and Chl-a were evenly distributed in the water column during the flooding period. However, 10% of NH 4 -N and 25% of DRP were removed in surface water (0-1m) when an algal bloom (Chl-a>30μgL -1 ) occurred 10days after peak discharge. Conversely, total particulate P (TPP) of surface water was 58% higher than in the deeper water. Dynamic factor analysis (DFA) revealed that TSM, NH 4 -N, DRP, total P and discharge significantly explain Chl-a variations following storms (C eff =0.89). These findings highlight that the reservoir ecosystem was vulnerable to pulse input from storm runoff and the Cyanophyta bloom was likely fueled by phosphate and ammonium rather than nitrate. Copyright © 2017 Elsevier B.V. All rights reserved.

Fertiliser management effects on dissolved inorganic nitrogen in runoff from Australian sugarcane farms.

PubMed

Fraser, Grant; Rohde, Ken; Silburn, Mark

2017-08-01

Dissolved inorganic nitrogen (DIN) movement from Australian sugarcane farms is believed to be a major cause of crown-of-thorns starfish outbreaks which have reduced the Great Barrier Reef coral cover by ~21% (1985-2012). We develop a daily model of DIN concentration in runoff based on >200 field monitored runoff events. Runoff DIN concentrations were related to nitrogen fertiliser application rates and decreased after application with time and cumulative rainfall. Runoff after liquid fertiliser applications had higher initial DIN concentrations, though these concentrations diminished more rapidly in comparison to granular fertiliser applications. The model was validated using an independent field dataset and provided reasonable estimates of runoff DIN concentrations based on a number of modelling efficiency score results. The runoff DIN concentration model was combined with a water balance cropping model to investigate temporal aspects of sugarcane fertiliser management. Nitrogen fertiliser application in December (start of wet season) had the highest risk of DIN movement, and this was further exacerbated in years with a climate forecast for 'wet' seasonal conditions. The potential utility of a climate forecasting system to predict forthcoming wet months and hence DIN loss risk is demonstrated. Earlier fertiliser application or reducing fertiliser application rates in seasons with a wet climate forecast may markedly reduce runoff DIN loads; however, it is recommended that these findings be tested at a broader scale.

A step towards considering the spatial heterogeneity of urban key features in urban hydrology flood modelling

NASA Astrophysics Data System (ADS)

Leandro, J.; Schumann, A.; Pfister, A.

2016-04-01

Some of the major challenges in modelling rainfall-runoff in urbanised areas are the complex interaction between the sewer system and the overland surface, and the spatial heterogeneity of the urban key features. The former requires the sewer network and the system of surface flow paths to be solved simultaneously. The latter is still an unresolved issue because the heterogeneity of runoff formation requires high detailed information and includes a large variety of feature specific rainfall-runoff dynamics. This paper discloses a methodology for considering the variability of building types and the spatial heterogeneity of land surfaces. The former is achieved by developing a specific conceptual rainfall-runoff model and the latter by defining a fully distributed approach for infiltration processes in urban areas with limited storage capacity dependent on OpenStreetMaps (OSM). The model complexity is increased stepwise by adding components to an existing 2D overland flow model. The different steps are defined as modelling levels. The methodology is applied in a German case study. Results highlight that: (a) spatial heterogeneity of urban features has a medium to high impact on the estimated overland flood-depths, (b) the addition of multiple urban features have a higher cumulative effect due to the dynamic effects simulated by the model, (c) connecting the runoff from buildings to the sewer contributes to the non-linear effects observed on the overland flood-depths, and (d) OSM data is useful in identifying pounding areas (for which infiltration plays a decisive role) and permeable natural surface flow paths (which delay the flood propagation).

Phosphorus loss to runoff water twenty-four hours after application of liquid swine manure or fertilizer.

PubMed

Tabbara, Hadi

2003-01-01

Phosphorus (P) added to soil from fertilizer or manure application could pose a threat to water quality due to its role in eutrophication of fresh water resources. Incorporating such amendments into the soil is an established best management practice (BMP) for reducing soluble P losses in runoff water, but could also lead to higher erosion. The objective of this study was to test whether incorporation of manure or fertilizer 24 h before an intense rain could also reduce sediment-bound and total phosphorus (TP) losses in runoff. A rainfall simulation study was conducted on field plots (sandy loam with 6-7% slope, little surface residue, recently cultivated) that received two application rates of liquid swine manure or liquid ammonium polyphosphate fertilizer, using either surface-broadcast or incorporated methods of application. Incorporation increased the total suspended solids (TSS) concentrations in runoff but mass losses were not affected. Incorporation also reduced flow-weighted concentrations and losses of dissolved reactive phosphorus (DRP) and TP by as much as 30 to 60% depending on source (fertilizer vs. manure) and application rate. Phosphorus is moved below the mixing zone of interaction on incorporation, and thus the effect of the amount and availability of P in this zone is more important than cultivation on subsequent P losses in runoff. Incorporating manure or fertilizer in areas of intense erosive rain, recent extensive tillage, and with little or no surface residue is therefore a best management practice that should be adhered to in order to minimize contamination of surface water. Results also show comparatively lower P losses from manure than fertilizer.

Using synthetic polymers to reduce soil erosion after forest fires in Mediterranean soils

NASA Astrophysics Data System (ADS)

Lado, Marcos; Ben-Hur, Meni; Inbar, Assaf

2010-05-01

Forest fires are a major environmental problem in the Mediterranean region because they result in a loss of vegetation cover, changes in biodiversity, increases in greenhouse gasses emission and a potential increase of runoff and soil erosion. The large increases in runoff and sediment yields after high severity fires have been attributed to several factors, among them: increase in soil water repellency; soil sealing by detached particles and by ash particles, and the loss of a surface cover. The presence of a surface cover increases infiltration, and decreases runoff and erosion by several mechanisms which include: rainfall interception, plant evapotranspiration, preservation of soil structure by increasing soil organic matter, and increasing surface roughness. The loss of vegetation cover as a result of fire leaves the surface of the soil exposed to the direct impact of the raindrops, and therefore the sensitivity of the soil to runoff generation and soil loss increases. In this work, we propose a new method to protect soils against post-fire erosion based on the application of synthetic polymers to the soil. Laboratory rainfall simulations and field runoff plots were used to analyze the suitability of the application of synthetic polymers to reduce soil erosion and stabilize soil structure in Mediterranean soils. The combination of these two processes will potentially favor a faster recovery of the vegetation structure. This method has been successfully applied in arable land, however it has not been tested in burnt forests. The outcome of this study may provide important managerial tools for forest management following fires.

Water quality of surface runoff and lint yield in cotton under furrow irrigation in Northeast Arkansas.

PubMed

Adviento-Borbe, M Arlene A; Barnes, Brittany D; Iseyemi, Oluwayinka; Mann, Amanda M; Reba, Michele L; Robertson, William J; Massey, Joseph H; Teague, Tina G

2018-02-01

Use of furrow irrigation in row crop production is a common practice through much of the Midsouth US and yet, nutrients can be transported off-site through surface runoff. A field study with cotton (Gossypium hirsutum, L.) was conducted to understand the impact of furrow tillage practices and nitrogen (N) fertilizer placement on characteristics of runoff water quality during the growing season. The experiment was designed as a randomized complete block design with conventional (CT) and conservation furrow tillage (FT) in combination with either urea (URN) broadcast or 32% urea ammonium nitrate (UAN) injected, each applied at 101kgNha -1 . Concentrations of ammonium (NH 4 -N), nitrate (NO 3 -N), nitrite (NO 2 -N), and dissolved phosphorus (P) in irrigation runoff water and lint yields were measured in all treatments. The intensity and chemical form of nutrient losses were primarily controlled by water runoff volume and agronomic practice. Across tillage and fertilizer N treatments, median N concentrations in the runoff were <0.3mgNL -1 , with NO 3 -N being relatively the highest among N forms. Concentrations of runoff dissolved P were <0.05mgPL -1 and were affected by volume of runoff water. Water pH, specific electrical conductivity, alkalinity and hardness were within levels that common to local irrigation water and less likely to impair pollution in waterways. Lint yields averaged 1111kgha -1 and were higher (P-value=0.03) in FT compared to CT treatments. Runoff volumes across irrigation events were greater (P-value=0.02) in CT than FT treatments, which increased NO 3 -N mass loads in CT treatments (394gNO 3 -Nha -1 season -1 ). Nitrate-N concentrations in CT treatments were still low and pose little threat to N contaminations in waterways. The findings support the adoption of conservation practices for furrow tillage and N fertilizer placement that can reduce nutrient runoff losses in furrow irrigation systems. Published by Elsevier B.V.

Coastal development and precipitation drive pathogen flow from land to sea: evidence from a Toxoplasma gondii and felid host system

PubMed Central

VanWormer, Elizabeth; Carpenter, Tim E; Singh, Purnendu; Shapiro, Karen; Wallender, Wesley W.; Conrad, Patricia A.; Largier, John L.; Maneta, Marco P.; Mazet, Jonna A. K.

2016-01-01

Rapidly developing coastal regions face consequences of land use and climate change including flooding and increased sediment, nutrient, and chemical runoff, but these forces may also enhance pathogen runoff, which threatens human, animal, and ecosystem health. Using the zoonotic parasite Toxoplasma gondii in California, USA as a model for coastal pathogen pollution, we examine the spatial distribution of parasite runoff and the impacts of precipitation and development on projected pathogen delivery to the ocean. Oocysts, the extremely hardy free-living environmental stage of T. gondii shed in faeces of domestic and wild felids, are carried to the ocean by freshwater runoff. Linking spatial pathogen loading and transport models, we show that watersheds with the highest levels of oocyst runoff align closely with regions of increased sentinel marine mammal T. gondii infection. These watersheds are characterized by higher levels of coastal development and larger domestic cat populations. Increases in coastal development and precipitation independently raised oocyst delivery to the ocean (average increases of 44% and 79%, respectively), but dramatically increased parasite runoff when combined (175% average increase). Anthropogenic changes in landscapes and climate can accelerate runoff of diverse pathogens from terrestrial to aquatic environments, influencing transmission to people, domestic animals, and wildlife. PMID:27456911

Coastal development and precipitation drive pathogen flow from land to sea: evidence from a Toxoplasma gondii and felid host system.

PubMed

VanWormer, Elizabeth; Carpenter, Tim E; Singh, Purnendu; Shapiro, Karen; Wallender, Wesley W; Conrad, Patricia A; Largier, John L; Maneta, Marco P; Mazet, Jonna A K

2016-07-26

Rapidly developing coastal regions face consequences of land use and climate change including flooding and increased sediment, nutrient, and chemical runoff, but these forces may also enhance pathogen runoff, which threatens human, animal, and ecosystem health. Using the zoonotic parasite Toxoplasma gondii in California, USA as a model for coastal pathogen pollution, we examine the spatial distribution of parasite runoff and the impacts of precipitation and development on projected pathogen delivery to the ocean. Oocysts, the extremely hardy free-living environmental stage of T. gondii shed in faeces of domestic and wild felids, are carried to the ocean by freshwater runoff. Linking spatial pathogen loading and transport models, we show that watersheds with the highest levels of oocyst runoff align closely with regions of increased sentinel marine mammal T. gondii infection. These watersheds are characterized by higher levels of coastal development and larger domestic cat populations. Increases in coastal development and precipitation independently raised oocyst delivery to the ocean (average increases of 44% and 79%, respectively), but dramatically increased parasite runoff when combined (175% average increase). Anthropogenic changes in landscapes and climate can accelerate runoff of diverse pathogens from terrestrial to aquatic environments, influencing transmission to people, domestic animals, and wildlife.

The impact of standard and hard-coded parameters on the hydrologic fluxes in the Noah-MP land surface model

NASA Astrophysics Data System (ADS)

Cuntz, Matthias; Mai, Juliane; Samaniego, Luis; Clark, Martyn; Wulfmeyer, Volker; Branch, Oliver; Attinger, Sabine; Thober, Stephan

2016-09-01

Land surface models incorporate a large number of process descriptions, containing a multitude of parameters. These parameters are typically read from tabulated input files. Some of these parameters might be fixed numbers in the computer code though, which hinder model agility during calibration. Here we identified 139 hard-coded parameters in the model code of the Noah land surface model with multiple process options (Noah-MP). We performed a Sobol' global sensitivity analysis of Noah-MP for a specific set of process options, which includes 42 out of the 71 standard parameters and 75 out of the 139 hard-coded parameters. The sensitivities of the hydrologic output fluxes latent heat and total runoff as well as their component fluxes were evaluated at 12 catchments within the United States with very different hydrometeorological regimes. Noah-MP's hydrologic output fluxes are sensitive to two thirds of its applicable standard parameters (i.e., Sobol' indexes above 1%). The most sensitive parameter is, however, a hard-coded value in the formulation of soil surface resistance for direct evaporation, which proved to be oversensitive in other land surface models as well. Surface runoff is sensitive to almost all hard-coded parameters of the snow processes and the meteorological inputs. These parameter sensitivities diminish in total runoff. Assessing these parameters in model calibration would require detailed snow observations or the calculation of hydrologic signatures of the runoff data. Latent heat and total runoff exhibit very similar sensitivities because of their tight coupling via the water balance. A calibration of Noah-MP against either of these fluxes should therefore give comparable results. Moreover, these fluxes are sensitive to both plant and soil parameters. Calibrating, for example, only soil parameters hence limit the ability to derive realistic model parameters. It is thus recommended to include the most sensitive hard-coded model parameters that were exposed in this study when calibrating Noah-MP.

Controlling Factors of the Surface Energy and Water Balances in cities located in cold climate regions

NASA Astrophysics Data System (ADS)

Järvi, L.; Grimmond, S. B.; Christen, A.; McFadden, J. P.; Strachan, I. B.

2016-12-01

Urban effects on climate are often pronounced in winter due to large anthropogenic heat releases and differences in snow cover between urban and surrounding rural areas. In this study, we simulate energy and water balances in cities characterized by cold winter climates with snow. Eleven urban sites from Helsinki (Finland), Basel (Switzerland), Montreal (Canada) and Minneapolis (USA) are analysed. The sites were selected based on the availability of either measured turbulent fluxes (from eddy covariance) or surface runoff to be used for model evaluation. The sites vary with respect to land cover fractions, irrigation habits and population densities. For example, the plan area fraction of impervious surface varies from 5% in Minneapolis to 84% in Basel. To simulate urban energy and water balances, we use the Surface Urban Energy and Water balance Scheme (SUEWS) model, which has been designed to minimize the number of required input variables and model parameters. For each site, the model is run in an offline mode using measured hourly meteorological data with a time step of 5-min. As the modelled time periods range from one (Basel) to 7.5 years (Helsinki), a wide range of meteorological conditions occur. Our results show how both evaporation and surface runoff are highly dependent on the fraction of impervious surface cover (r > |0.8|) during snow-free periods. However, high year-to-year variability in simulated evaporation and runoff indicates that climatological factors are also important. In winter, the amount and duration of snow cover become import controlling factor in determining the two components of water balance. The shorter the snow cover period is, the larger the cumulative runoff tends to be. Thus, our results suggest that warmer winters with less snow will increase the stress on drainage systems and modify the urban ecosystem via changes in evaporation and Bowen ratio. Also, our results indicate that simply using the fraction of impervious or pervious surfaces when estimating the surface runoff at different sites is not sufficient, but rather inter-annual variability in climatology also needs to be considered.

Retrofitting with bioretention and a swale to treat bridge deck stormwater runoff.

DOT National Transportation Integrated Search

2010-07-28

Stormwater runoff from roadways is a source of surface water pollution in North Carolina. The North Carolina Department of Transportation (NCDOT) is required to implement stormwater control measures (SCMs) in the linear environment. NCDOT has specifi...

Green Retrofit Technology for Detention Basin Outlet Control Structures

EPA Science Inventory

Urbanization and improperly managed impervious surfaces alters the hydrology of a watershed, leading to increased runoff volumes, higher and/or longer lasting peak flows, and more frequent runoff events. These hydrologic and hydraulic modifications can impact every aspect of stre...

Designing Bioretention Systems to Improve Nitrogen Removal - poster

EPA Science Inventory

Rain gardens, also referred to as bioretention systems, are designed primarily to infiltrate stormwater flow and reduce surface runoff and peak flows to receiving streams. Additionally, they are known to remove stressors from urban stormwater runoff, including oil and grease, pho...

Forecasting runoff from Pennsylvania landscapes

USDA-ARS?s Scientific Manuscript database

Identifying sites prone to surface runoff has been a cornerstone of conservation and nutrient management programs, relying upon site assessment tools that support strategic, as opposed to operational, decision making. We sought to develop simple, empirical models to represent two highly different me...

Reduction of nonpoint source contamination of surface water and groundwater by starch encapsulation of herbicides

USGS Publications Warehouse

Mills, M.S.; Thurman, E.M.

1994-01-01

The loss of the preemergent herbicide atrazine in surface runoff from experimental field plots growing corn (Zea mays L.) was significantly reduced using a starchencapsulated formulation versus a conventional powdered formulation. Field edge losses of starch-encapsulated atrazine were described as following a Rayleigh distribution totaling 1.8% of applied herbicide compared to exponential powdered atrazine losses of 2.9% applied - a 40% decrease. This has important implications for the reduction of nonpoint source contamination of surface water by agricultural chemicals. Unsaturated zone release of starchencapsulated atrazine was gradual, but comparable weed control was maintained. Deethylatrazine was a major dealkylated metabolite from each formulation, and deisopropylatrazine was a minor metabolite. The determination of soil partition coefficients for deethylatrazine and deisopropylatrazine (0.4 and 0.3, respectively), aqueous solubilities (3200 and 670 mg/L, respectively), and melting points (133 and 177 ??C, respectively) confirmed that the dealkylated metabolites should move more rapidly through the soil profile to groundwater than atrazine.

Precipitation-runoff and streamflow-routing models for the Willamette River basin, Oregon

USGS Publications Warehouse

Laenen, Antonius; Risley, John C.

1997-01-01

With an input of current streamflow, precipitation, and air temperature data the combined runoff and routing models can provide current estimates of streamflow at almost 500 locations on the main stem and major tributaries of the Willamette River with a high degree of accuracy. Relative contributions of surface runoff, subsurface flow, and ground-water flow can be assessed for 1 to 10 HRU classes in each of 253 subbasins identified for precipitation-runoff modeling. Model outputs were used with a water-quality model to simulate the movement of dye in the Pudding River as an example

A simple rainfall-runoff model based on hydrological units applied to the Teba catchment (south-east Spain)

NASA Astrophysics Data System (ADS)

Donker, N. H. W.

2001-01-01

A hydrological model (YWB, yearly water balance) has been developed to model the daily rainfall-runoff relationship of the 202 km2 Teba river catchment, located in semi-arid south-eastern Spain. The period of available data (1976-1993) includes some very rainy years with intensive storms (responsible for flooding parts of the town of Malaga) and also some very dry years.The YWB model is in essence a simple tank model in which the catchment is subdivided into a limited number of meaningful hydrological units. Instead of generating per unit surface runoff resulting from infiltration excess, runoff has been made the result of storage excess. Actual evapotranspiration is obtained by means of curves, included in the software, representing the relationship between the ratio of actual to potential evapotranspiration as a function of soil moisture content for three soil texture classes.The total runoff generated is split between base flow and surface runoff according to a given baseflow index. The two components are routed separately and subsequently joined. A large number of sequential years can be processed, and the results of each year are summarized by a water balance table and a daily based rainfall runoff time series. An attempt has been made to restrict the amount of input data to the minimum.Interactive manual calibration is advocated in order to allow better incorporation of field evidence and the experience of the model user. Field observations allowed for an approximate calibration at the hydrological unit level.

The role of stochastic storms on hillslope runoff generation and connectivity in a dryland basin

NASA Astrophysics Data System (ADS)

Michaelides, K.; Singer, M. B.; Mudd, S. M.

2016-12-01

Despite low annual rainfall, dryland basins can generate significant surface runoff during certain rainstorms, which can cause flash flooding and high rates of erosion. However, it remains challenging to anticipate the nature and frequency of runoff generation in hydrological systems which are driven by spatially and temporally stochastic rainstorms. In particular, the stochasticity of rainfall presents challenges to simulating the hydrological response of dryland basins and understanding flow connectivity from hillslopes to the channel. Here we simulate hillslope runoff generation using rainfall characteristics produced by a simple stochastic rainfall generator, which is based on a rich rainfall dataset from the Walnut Gulch Experimental Watershed (WGEW) in Arizona, USA. We assess hillslope runoff generation using the hydrological model, COUP2D, driven by a subset of characteristic output from multiple ensembles of decadal monsoonal rainfall from the stochastic rainfall generator. The rainfall generator operates across WGEW by simulating storms with areas smaller than the basin and enables explicit characterization of rainfall characteristics at any location. We combine the characteristics of rainfall intensity and duration with data on rainstorm area and location to model the surface runoff properties (depth, velocity, duration, distance downslope) on a range of hillslopes within the basin derived from LiDAR analysis. We also analyze connectivity of flow from hillslopes to the channel for various combinations of hillslopes and storms. This approach provides a framework for understanding spatial and temporal dynamics of runoff generation and connectivity that is faithful to the hydrological characteristics of dryland environments.

Innovative interdisciplinary approaches in catchment hydrology: on the potential for diatoms and thermal infrared imagery for documenting spatio-temporal dynamics and connectivity of saturated areas in the hillslope-riparian zone-stream system

NASA Astrophysics Data System (ADS)

Pfister, L.; Martínez-Carreras, N.; Wetzel, C.; Ector, L.; Frentress, J.; McDonnell, J. J.

2012-04-01

Over the past decades, hydrologists have been relentlessly investigating water source, flowpaths and residence time. These issues are of paramount importance when it comes to both the quantitative and qualitative management of water resources. Support from the scientific community has indeed been repeatedly sollicited by the European Union in the context of an optimization of the implementation of its framework directives on water quality and floods. However, to date large uncertainties remain adjunct to our measurements of hydrological processes on the one hand and the modelling of the precipitation-runoff relationship on the other hand. Originally, investigations on the rainfall-runoff transformation were based on conventional geochemical and isotopic tracing techniques. Unfortunately, well-known and documented technical limitations (e.g. non-stable end-members, incomplete mixing assumptions) have rapidly stymied further progress in our understanding of the rainfall-runoff transformation. More recently, technological progress has created new potential for going well beyond the traditional sources of information, such as rainfall and discharge. New measuring techniques have been recently introduced (e.g. thermographic systems such as temperature fiber optic cables and thermal IR cameras for tracing water source and flowpaths, satellite aperture radar for measuring flood extents and/or soil humidity, laser spectrometers for stable isotope measurements, etc.). Indeed the rainfall-runoff transformation inside a catchment is the result of a plethora of interrelated processes that go well beyond water movements. As a consequence, it is crucial to the development of hydrological science to integrate the advances and knowledge from different disciplines. In other terms, knowledge from ecology, biology, as well as other sciences is needed to better understand the functioning of catchments. We need to work together on common problems to find better solutions In recent years, our research activities have been focusing on the exploration of new research avenues for untapping new insights on inherent hydrological processes, guiding water source and flowpaths. Here, we will present the most recent results obtained to date from interdisciplinary proof-of-concept studies carried out in the Weierbach experimental watershed. New research avenues, such as the introduction of terrestrial diatom tracing in flood waves, will hopefully contribute to reduce uncertainties in the determination of the onset/cessation of surface runoff and connectivity in the hillslope-riparian zone-stream system. Likewise, thermal infrared imaging has shown considerable potential for tracing surface water flowpaths, connectivity, as well as saturated area dynamics.

Accounting for temporal variation in soil hydrological properties when simulating surface runoff on tilled plots

NASA Astrophysics Data System (ADS)

Chahinian, Nanée; Moussa, Roger; Andrieux, Patrick; Voltz, Marc

2006-07-01

Tillage operations are known to greatly influence local overland flow, infiltration and depressional storage by altering soil hydraulic properties and soil surface roughness. The calibration of runoff models for tilled fields is not identical to that of untilled fields, as it has to take into consideration the temporal variability of parameters due to the transient nature of surface crusts. In this paper, we seek the application of a rainfall-runoff model and the development of a calibration methodology to take into account the impact of tillage on overland flow simulation at the scale of a tilled plot (3240 m 2) located in southern France. The selected model couples the (Morel-Seytoux, H.J., 1978. Derivation of equations for variable rainfall infiltration. Water Resources Research. 14(4), 561-568). Infiltration equation to a transfer function based on the diffusive wave equation. The parameters to be calibrated are the hydraulic conductivity at natural saturation Ks, the surface detention Sd and the lag time ω. A two-step calibration procedure is presented. First, eleven rainfall-runoff events are calibrated individually and the variability of the calibrated parameters are analysed. The individually calibrated Ks values decrease monotonously according to the total amount of rainfall since tillage. No clear relationship is observed between the two parameters Sd and ω, and the date of tillage. However, the lag time ω increases inversely with the peakflow of the events. Fairly good agreement is observed between the simulated and measured hydrographs of the calibration set. Simple mathematical laws describing the evolution of Ks and ω are selected, while Sd is considered constant. The second step involves the collective calibration of the law of evolution of each parameter on the whole calibration set. This procedure is calibrated on 11 events and validated on ten runoff inducing and four non-runoff inducing rainfall events. The suggested calibration methodology seems robust and can be transposed to other gauged sites.

[Comparison of nitrogen loss via surface runoff from two agricultural catchments in semi-arid North China].

PubMed

Lu, Hai-Ming; Yin, Cheng-Qing; Wang, Xia-Hui; Zou, Ying

2008-10-01

Nitrogen loss characteristics via surface runoff from two typical agricultural catchments into Yuqiao Reservoir--the important drinking water source area for Tianjin city in semi-arid North China were investigated through two-year in-situ monitoring and indoor chemical analysis. The results showed that annual nitrogen export mainly concentrated in the rainy period between June to September. About 41% of the annual water output and 52% of the annual total nitrogen output took place in two rainfall events with rainfall> 60 mm in Taohuasi catchment (T catchment), while the distribution of water and nitrogen export among various rainfalls in Caogezhuang catchment (C catchment) was smooth. The rainfall thresholds for the appearance of water and nitrogen export from the outlet of T catchment and C catchment were 20 mm and 10 mm. The mean annual runoff coefficients of C and T catchments were 0.013 2 and 0.001 6, respectively. The mean annual total nitrogen exports from C catchment and T catchment were 1.048 kg x (hm2 x a)(-1) and 0.158 kg x (hm2 x a)(-1) respectively. The difference of micro-topography, landscape pattern and hydrological pathway between two catchments could explain the nitrogen export gap. Micro-topographical features created by long-term anthropological disturbance decrease the runoff generation ability. The distance between nitrogen source area and the outlet in T catchment was around 1 500 m, while such distance in C catchment was just around 200 m. The short distance added the nitrogen export risk via surface runoff. Road-type hydrological pathway in C catchment could transfer nitrogen into the receiving water via surface runoff directly, while nitrogen could be detained within the pathway by many sink structures such as small stones, vegetated buffer strip and dry ponds in T catchment.

Concentrations of polycyclic aromatic hydrocarbons (PAHs) and major and trace elements in simulated rainfall runoff from parking lots, Austin, Texas, 2003

USGS Publications Warehouse

Mahler, Barbara J.; Van Metre, Peter C.; Wilson, Jennifer T.

2004-01-01

Samples of creek bed sediment collected near seal-coated parking lots in Austin, Texas, by the City of Austin during 2001–02 had unusually elevated concentrations of polycyclic aromatic hydrocarbons (PAHs). To investigate the possibility that PAHs from seal-coated parking lots might be transported to urban creeks, the U.S. Geological Survey, in cooperation with the City of Austin, sampled runoff and scrapings from four test plots and 13 urban parking lots. The surfaces sampled comprise coal-tar-emulsion-sealed, asphalt-emulsion-sealed, unsealed asphalt, and unsealed concrete. Particulates and filtered water in runoff and surface scrapings were analyzed for PAHs. In addition, particulates in runoff were analyzed for major and trace elements. Samples of all three media from coal-tar-sealed parking lots had concentrations of PAHs higher than those from any other types of surface. The mean total PAH concentration in particulates in runoff from parking lots in use were 3,500,000, 620,000, and 54,000 micrograms per kilogram from coal-tar-sealed, asphalt-sealed, and unsealed (asphalt and concrete combined) lots, respectively. The probable effect concentration sediment quality guideline is 22,800 micrograms per kilogram. The mean total PAH (sum of detected PAHs) concentration in filtered water from parking lots in use was 8.6 micrograms per liter for coal-tar-sealed lots; the one sample analyzed from an asphalt-sealed lot had a concentration of 5.1 micrograms per liter and the one sample analyzed from an unsealed asphalt lot was 0.24 microgram per liter. The mean total PAH concentration in scrapings was 23,000,000, 820,000, and 14,000 micrograms per kilogram from coal-tar-sealed, asphalt-sealed, and unsealed asphalt lots, respectively. Concentrations of lead and zinc in particulates in runoff frequently exceeded the probable effect concentrations, but trace element concentrations showed no consistent variation with parking lot surface type.

Final Environmental Assessment for the Military Housing Privatization Initiative at Soundside Manor at Hurlburt Field, Florida

DTIC Science & Technology

2014-09-30

infrastructure to minimize stormwater runoff with minimal impact to the floodplain. The Environmental Assessment (EA), incorporated by reference into this finding...stabilizing vegetation that could result in increased stormwater runoff and erosion. Generally, soils within the affected environment are flat and...The key issues of concern are the potential for the transport of soils through erosion caused by stormwater runoff from nonvegetated surface areas

Interception of rainfall and surface runoff in the Brazilian Cerrado

NASA Astrophysics Data System (ADS)

Tarso Oliveira, Paulo; Wendland, Edson; Nearing, Mark; Perea Martins, João

2014-05-01

The Brazilian Cerrado plays a fundamental role in water resources dynamics because it distributes fresh water to the largest basins in Brazil and South America. In recent decades, the native Cerrado vegetation has increasingly been replaced by agricultural crops and pasture. These land cover and land use changes have altered the hydrological processes. Meanwhile, little is known about the components of the water balance in the Brazilian Cerrado, mainly because the experimental field studies in this region are scarce or nonexistent. The objective of this study was to evaluate two hydrological processes under native Cerrado vegetation, the canopy interception (CI) and the surface runoff (R). The Cerrado physiognomy was classified as "cerrado sensu stricto denso" with an absolute density of 15,278 trees ha-1, and a basal area of 11.44 m2 ha-1. We measured the gross rainfall (P) from an automated tipping bucket rain gauge (model TB4) located in a tower with 11 m of height on the Cerrado. Throughfall (TF) was obtained from 15 automated tipping bucket rain gauges (model Davis) spread below the Cerrado vegetation and randomly relocated every month during the wet season. Stemflow (SF) was measured on 12 trees using a plastic hose wrapped around the trees trunks, sealed with neutral silicone sealant, and a bucket to store the water. The canopy interception was computed by the difference between P and the sum of TF and SF. Surface runoff under undisturbed Cerrado was collected in three plots of 100 m2(5 x 20 m) in size and slope steepness of approximately 0.09 m m-1. The experimental study was conducted between January 2012 and November 2013. We found TF of 81.0% of P and SF of 1.6% of P, i.e. the canopy interception was calculated at 17.4% of P. There was a statistically significant correlation (p < 0.05) between gross rainfall and TF, SF, and CI with correlation coefficients r > 0.8. Our results suggest that the rainfall intensity, the characteristics of the trees trunks (crooked and twisted) and stand structure are the main factors that have influenced CI. The average surface runoff under undisturbed Cerrado was less than 1% of the P, and did not have significant correlation (p > 0.05) with P, but had a significant correlation with maximum 30 minute rainfall intensity (I30). This low value for surface runoff indicates that the forest ?oor has a strong influence over surface runoff generation under undisturbed Cerrado. This process is poorly studied; however, we believe this can be a key to understanding the surface runoff generation under undisturbed Cerrado, and in other tropical vegetation, such as the Amazon rainforest.

Using Rapid Indicators for Enterococcus to Assess the Risk of Illness after Exposure to Urban Runoff Contaminated Marine Water

PubMed Central

Colford, John M.; Schiff, Kenneth C.; Griffith, John F.; Yau, Vince; Arnold, Benjamin F.; Wright, Catherine C.; Gruber, Joshua S.; Wade, Timothy J.; Burns, Susan; Hayes, Jacqueline; McGee, Charles; Gold, Mark; Cao, Yiping; Noble, Rachel T.; Haugland, Richard; Weisberg, Stephen B.

2012-01-01

Background Traditional fecal indicator bacteria (FIB) measurement is too slow (>18 hr) for timely swimmer warnings. Objectives Assess relationship of rapid indicator methods (qPCR) to illness at a marine-beach impacted by urban-runoff. Methods We measured baseline and two-week health in 9525 individuals visiting Doheny Beach 2007-08. Illness rates were compared (swimmers vs. non-swimmers). FIB measured by traditional (Enterococcus spp. by EPA Method 1600 or Enterolert™, fecal coliforms, total coliforms) and three rapid qPCR assays for Enterococcus spp. (Taqman, Scorpion-1, Scorpion-2) were compared to health. Primary bacterial source was a creek flowing untreated into ocean; the creek did not reach the ocean when a sand berm formed. This provided a natural experiment for examining FIB-health relationships under varying conditions. Results We observed significant increases in diarrhea (OR1.90, 95% CI 1.29-2.80 for swallowing water) and other outcomes in swimmers compared to non-swimmers. Exposure (body immersion, head immersion, swallowed water) was associated with increasing risk of gastrointestinal illness (GI). Daily GI incidence patterns were different: swimmers (2-day peak ) and non-swimmers (no peak). With berm-open, we observed associations between GI and traditional and rapid methods for Enterococcus; fewer associations occurred when berm status was not considered. Conclusions We found increased risk of GI at this urban-runoff beach. When FIB source flowed freely (berm-open), several traditional and rapid indicators were related to illness. When FIB source was weak (berm-closed) fewer illness-associations were seen. These different relationships under different conditions at a single beach demonstrate the difficulties using these indicators to predict health risk. PMID:22356828

Satellite-derived land covers for runoff estimation using SCS-CN method in Chen-You-Lan Watershed, Taiwan

NASA Astrophysics Data System (ADS)

Zhang, Wen-Yan; Lin, Chao-Yuan

2017-04-01

The Soil Conservation Service Curve Number (SCS-CN) method, which was originally developed by the USDA Natural Resources Conservation Service, is widely used to estimate direct runoff volume from rainfall. The runoff Curve Number (CN) parameter is based on the hydrologic soil group and land use factors. In Taiwan, the national land use maps were interpreted from aerial photos in 1995 and 2008. Rapid updating of post-disaster land use map is limited due to the high cost of production, so the classification of satellite images is the alternative method to obtain the land use map. In this study, Normalized Difference Vegetation Index (NDVI) in Chen-You-Lan Watershed was derived from dry and wet season of Landsat imageries during 2003 - 2008. Land covers were interpreted from mean value and standard deviation of NDVI and were categorized into 4 groups i.e. forest, grassland, agriculture and bare land. Then, the runoff volume of typhoon events during 2005 - 2009 were estimated using SCS-CN method and verified with the measured runoff data. The result showed that the model efficiency coefficient is 90.77%. Therefore, estimating runoff by using the land cover map classified from satellite images is practicable.

Treatment of suspended solids and heavy metals from urban stormwater runoff by a tree box filter.

PubMed

Geronimo, F K F; Maniquiz-Redillas, M C; Tobio, J A S; Kim, L H

2014-01-01

Particulates, inorganic and toxic constituents are the most common pollutants associated with urban stormwater runoff. Heavy metals such as chromium, nickel, copper, zinc, cadmium and lead are found to be in high concentration on paved roads or parking lots due to vehicle emissions. In order to control the rapid increase of pollutant loads in stormwater runoff, the Korean Ministry of Environment proposed the utilization of low impact developments. One of these was the application of tree box filters that act as a bioretention treatment system which executes filtration and sorption processes. In this study, a tree box filter located adjacent to an impervious parking lot was developed to treat suspended solids and heavy metal concentrations from urban stormwater runoff. In total, 11 storm events were monitored from July 2010 to August 2012. The results showed that the tree box filter was highly effective in removing particulates (up to 95%) and heavy metals (at least 70%) from the urban stormwater runoff. Furthermore, the tree box filter was capable of reducing the volume runoff by 40% at a hydraulic loading rate of 1 m/day and below.

[Monitoring and analysis on evolution process of rainfall runoff water quality in urban area].

PubMed

Dong, Wen; Li, Huai-En; Li, Jia-Ke

2013-02-01

In order to find the water quality evolution law and pollution characteristics of the rainfall runoff from undisturbed to the neighborhood exit, 6 times evolution process of rainfall runoff water quality were monitored and analyzed from July to October in 2011, and contrasted the clarification efficiency of the grassland to the roof runoff rudimentarily at the same time. The research showed: 1. the results of the comparison from "undisturbed, rainfall-roof, rainfall runoff-road, rainfall-runoff the neighborhood exit runoff " showed that the water quality of the undisturbed rain was better than that from the roof and the neighborhood exist, but the road rainfall runoff water quality was the worst; 2. the average concentrations of the parameters such as COD, ammonia nitrogen and total nitrogen all exceeded the Fifth Class of the Surface Water Quality Standard except for the soluble total phosphorus from undisturbed rainfall to the neighborhood exit; 3. the runoff water quality of the short early fine days was better than that of long early fine days, and the last runoff water quality was better than that of the initial runoff in the same rainfall process; 4. the concentration reduction of the grassland was notable, and the reduction rate of the grassland which is 1.0 meter wide of the roof runoff pollutants such as COD and nitrogen reached 30%.

Spatial and temporal variations in non-point source losses of nitrogen and phosphorus in a small agricultural catchment in the Three Gorges Region.

PubMed

Chen, Chenglong; Gao, Ming; Xie, Deti; Ni, Jiupai

2016-04-01

Losses of agricultural pollutants from small catchments are a major issue for water quality in the Three Gorges Region. Solutions are urgently needed. However, before pollutant losses can be controlled, information about spatial and temporal variations in pollutant losses is needed. The study was carried out in the Wangjiagou catchment, a small agricultural catchment in Fuling District, Chongqing, and the data about non-point source losses of nitrogen and phosphorus was collected here. Water samples were collected daily by an automatic water sampler at the outlets of two subcatchments from 2012 to 2014. Also, samples of surface runoff from 28 sampling sites distributed through the subcatchments were collected during 12 rainfall events in 2014. A range of water quality variables were analyzed for all samples and were used to demonstrate the variation in non-point losses of nitrogen and phosphorus over a range of temporal and spatial scales and in different types of rainfall in the catchment. Results showed that there was a significant linear correlation between the mass concentrations of total nitrogen (TN) and nitrate (NO3-N) in surface runoff and that the relationship was maintained with changes in time. Concentrations of TN and NO3-N peaked after fertilizer was applied to crops in spring and autumn; concentrations decreased rapidly after the peak values in spring but declined slowly in autumn. N and P concentrations fluctuated more and showed a greater degree of dispersion during the spring crop cultivation period than those in autumn. Concentrations of TN and NO3-N in surface runoff were significantly and positively correlated with the proportion of the area that was planted with corn and mustard tubers, but were negatively correlated with the proportion of the area taken up with rice and mulberry plantations. The average concentrations of TN and NO3-N in surface runoff reached the highest level from the sampling points at the bottom of the land used for corn only, but lowest in rice fields. Slope gradient had a significant positive correlation with TN’s and total phosphorus (TP)’s concentration losses. Concentrations of TN, NO3-N, and total phosphorus were significantly correlated with rainfall. Peak concentrations of ammoniacal nitrogen occurred during the fertilizer application period in spring and autumn. Different structures of land use types had a significant influence on the concentration losses of nitrogen and phosphorus; thus, using a reasonable way to adjust land use structure and spatial arrangement of whole catchment was an effective solution to control non-point source pollution of the Three Gorges Region.

Notes on a Mesodinium rubrum red tide in San Francisco Bay (California, USA)

USGS Publications Warehouse

Cloern, James E.; Cole, Brian E.; Hager, Stephen W.

1994-01-01

Discrete red patches of water were observed in South San Francisco Bay (USA) on 30 April 1993, and examination of live samples showed that this red tide was caused by surface accumulations of the pigmented ciliate Mesodinium rubrum . Vertical profiles showed strong salinity and temperature stratification in the upper 5 m, peak chlorophyll fluorescence in the upper meter, and differences in the small-scale density structure and fluorescence distribution among red patches. Events preceding this Mesodinium red tide included: (i) heavy precipitation and run-off, allowing for strong salinity stratification; (ii) a spring diatom bloom where the chlorophyll a concentration reached 50 mg m −3 ; (ii) depletions of dissolved inorganic N and Si in the photic zone; and (iv) several days of rapid warming and stabilization of the upper surface layer. These conditions may be general prerequisites for M.rubrum blooms in temperate estuaries.

Modeling effect of cover condition and soil type on rotavirus transport in surface flow.

PubMed

Bhattarai, Rabin; Davidson, Paul C; Kalita, Prasanta K; Kuhlenschmidt, Mark S

2017-08-01

Runoff from animal production facilities contains various microbial pathogens which pose a health hazard to both humans and animals. Rotavirus is a frequently detected pathogen in agricultural runoff and the leading cause of death among children around the world. Diarrheal infection caused by rotavirus causes more than two million hospitalizations and death of more than 500,000 children every year. Very little information is available on the environmental factors governing rotavirus transport in surface runoff. The objective of this study is to model rotavirus transport in overland flow and to compare the model results with experimental observations. A physically based model, which incorporates the transport of infective rotavirus particles in both liquid (suspension or free-floating) and solid phase (adsorbed to soil particles), has been used in this study. Comparison of the model results with experimental results showed that the model could reproduce the recovery kinetics satisfactorily but under-predicted the virus recovery in a few cases when multiple peaks were observed during experiments. Similarly, the calibrated model had a good agreement between observed and modeled total virus recovery. The model may prove to be a promising tool for developing effective management practices for controlling microbial pathogens in surface runoff.

Blue Water Trade-Offs With Vegetation in a CO2-Enriched Climate

NASA Astrophysics Data System (ADS)

Mankin, Justin S.; Seager, Richard; Smerdon, Jason E.; Cook, Benjamin I.; Williams, A. Park; Horton, Radley M.

2018-04-01

Present and future freshwater availability and drought risks are physically tied to the responses of surface vegetation to increasing CO2. A single-model large ensemble identifies the occurrence of colocated warming- and CO2-induced leaf area index increases with summer soil moisture declines. This pattern of "greening" and "drying," which occurs over 42% of global vegetated land area, is largely attributable to changes in the partitioning of precipitation at the land surface away from runoff and toward terrestrial vegetation ecosystems. Changes in runoff and ecosystem partitioning are inversely related, with changes in runoff partitioning being governed by changes in precipitation (mean and extremes) and ecosystem partitioning being governed by ecosystem water use and surface resistance to evapotranspiration (ET). Projections show that warming-influenced and CO2-enriched terrestrial vegetation ecosystems use water that historically would have been partitioned to runoff over 48% of global vegetated land areas, largely in Western North America, the Amazon, and Europe, many of the same regions with colocated greening and drying. These results have implications for how water available for people will change in response to anthropogenic warming and raise important questions about model representations of vegetation water responses to high CO2.

Waste water compliance: staying on the offense

USDA-ARS?s Scientific Manuscript database

Cattlemen and regulators are interested in safe and effective environmental stewardship of beef production. Recent interest has focused on better management of runoff storage. Typically, storage ponds hold feedlot surface runoff until it can be applied to crops. While stored, the nutrient laden w...

MANURE HARVESTING PRACTICES: EFFECTS ON WASTE CHARACTERISTICS AND RUNOFF

EPA Science Inventory

To develop a basis for better manure harvesting management practices a combined field and laboratory study was conducted. The effect of management practices on manure qualities and runoff pollution potential were compared on three feedlot pens with fully surfaced, partially surfa...

Landscape influence on soil carbon and nutrient levels

USDA-ARS?s Scientific Manuscript database

Past runoff, erosion, and management practices influence nutrient levels on the landscape. These starting levels affect future nutrient transport due to runoff, erosion, and leaching events. The purpose of this study was to examine closed-depression landscape effects on surface soil organic matter, ...

Runoff and erosion from a rapidly eroding pinyon-juniper hillslope

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilcox, B.P.; Davenport, D. W.; Pitlick, J.

1996-02-01

The dramatic acceleration of erosion associated with the expansion of pinyon-juniper woodlands over the past 100 years has been a widely recognized but poorly understood phenomenon. A more complete understanding will come only through long-term observations of erosion and related factors. To this end, we are conducting a study of a small (1-ha) catchment in a rapidly eroding pinyon-juniper woodland. Since July 1993, we have been collecting data on runoff, erosion, and weather conditions in the catchment, as well as on the topography, soils, and vegetation. Our preliminary results suggest that (1) the catchment is currently in a cycle ofmore » accelerated erosion that began concomitant with a shift from ponderosa pine forest to pinyon-juniper woodland that was initiated by a prolonged drought; (2) the intercanopy soils cannot be sustained at the current erosion rates and will be mostly stripped away in about a century; (3) large summer thunderstorms are the most important agents of erosion (4) erosion increases dramatically as the scale increases; (5) runoff makes up <10% of the water budget.« less

Greenland meltwater storage in firn limited by near-surface ice formation

NASA Astrophysics Data System (ADS)

Machguth, Horst; Macferrin, Mike; van As, Dirk; Box, Jason E.; Charalampidis, Charalampos; Colgan, William; Fausto, Robert S.; Meijer, Harro A. J.; Mosley-Thompson, Ellen; van de Wal, Roderik S. W.

2016-04-01

Approximately half of Greenland’s current annual mass loss is attributed to runoff from surface melt. At higher elevations, however, melt does not necessarily equal runoff, because meltwater can refreeze in the porous near-surface snow and firn. Two recent studies suggest that all or most of Greenland’s firn pore space is available for meltwater storage, making the firn an important buffer against contribution to sea level rise for decades to come. Here, we employ in situ observations and historical legacy data to demonstrate that surface runoff begins to dominate over meltwater storage well before firn pore space has been completely filled. Our observations frame the recent exceptional melt summers in 2010 and 2012 (refs ,), revealing significant changes in firn structure at different elevations caused by successive intensive melt events. In the upper regions (more than ~1,900 m above sea level), firn has undergone substantial densification, while at lower elevations, where melt is most abundant, porous firn has lost most of its capability to retain meltwater. Here, the formation of near-surface ice layers renders deep pore space difficult to access, forcing meltwater to enter an efficient surface discharge system and intensifying ice sheet mass loss earlier than previously suggested.

Effect of growth promotants on the occurrence of endogenous and synthetic steroid hormones on feedlot soils and in runoff from beef cattle feeding operations.

PubMed

Bartelt-Hunt, Shannon L; Snow, Daniel D; Kranz, William L; Mader, Terry L; Shapiro, Charles A; Donk, Simon J van; Shelton, David P; Tarkalson, David D; Zhang, Tian C

2012-02-07

Supplements and growth promotants containing steroid hormones are routinely administered to beef cattle to improve feeding efficiency, reduce behavioral problems, and enhance production. As a result, beef cattle manure will contain both synthetic steroids as well as a range of endogenous steroids including androgens, estrogens, and progestogens. A two-year controlled study was conducted in which beef cattle were administered steroid hormones via subcutaneous implants and feed additives and the occurrence of 16 endogenous and synthetic steroid hormones and metabolites was evaluated in runoff from beef cattle feedlots and in manure and soil collected from feedlot surfaces. Samples were extracted and analyzed using liquid chromatography tandem mass spectrometryfor metabolites of the synthetic androgen trenbolone acetate, 17α-trenbolone, 17β-trenbolone, for the nonsteroidal semisynthetic estrogen agonist, α-zearalanol, and the synthetic progesterone melengesterol acetate, as well as a wide range of endogeneous estrogens, androgens, and fusarium metabolites. Synthetic steroids including trenbolone metabolites and melengestrol acetate were detected in fresh manure and in feedlot surface soils from cattle administered synthetic steroids at concentrations up to 55 ± 22 ng/g dry weight (dw) (17α-trenbolone) and 6.5 ± 0.4 ng/g dw (melengesterol acetate). Melengesterol acetate was detected in 6% of runoff samples from feedlots holding cattle administered synthetic steroids at concentrations ranging up to 115 ng/L. The presence of melengesterol acetate in runoff from beef cattle feeding operations has not been previously reported. Synthetic steroids were not detected in manure or runoff from control cattle. A wide range of endogenous hormones were detected in runoff and feedlot surface soils and manure from cattle given synthetic steroids and from control cattle, with no statistically significant differences in concentration. These results indicate that runoff from confined animal production facilities is of environmental and public health concern regardless of the use of growth promotants.

Estrogenic activity and nutrient losses in surface runoff after winter manure application to small watersheds.

PubMed

Shappell, N W; Billey, L O; Shipitalo, M J

2016-02-01

Confined Animal Feeding Operations generate large amounts of wastes that are land-applied to provide nutrients for crop production and return organic matter to the soil. Production practices and storage limitations often necessitate that wastes be applied to frozen and snow-covered soil. Use of application setbacks have reduced concerns related to nutrient losses in surface runoff from manure, but the estrogenic activity of runoff under these conditions has not been evaluated. Therefore, we measured and sampled surface runoff when manure was applied in the winter at a rate to meet crop N needs and measured estradiol equivalents (E2Eqs) using E-Screen. In year one, six small watersheds used to produce corn were evaluated, treatments: 2 no-manure controls, 2 liquid swine manure with 30-m setbacks, and 2 turkey litter with 30-m setbacks. In addition, beef manure was applied to six frozen plots of forage. For years 2 and 3, applications were repeated on the swine manure watersheds and one control watershed. E2Eqs and nutrient concentrations generally peaked in the first runoff event after application. The highest measured E2Eq (5.6 ng L(-1)) was in the first event after swine manure application and was less than the 8.9 ng L(-1) Lowest Observable Effect Concentration (LOEC) for aquatic species and well below the concentrations measured in other studies using ELISAs to measure hormone concentrations. No runoff occurred from plots planted with forage, indicating low risk for environmental impact, and therefore plots were discontinued from study. In years 2 and 3, estrogenic activity never exceeded the Predicted No Effect Concentrations for E2 of 2 ng L(-1). When post-application runoff contained high estrogenic activity, strong correlations (R(2) 0.86 to 0.96) of E2Eq to Ca(2+), Mg(2+), and K(+) concentrations were observed, indicating under some condition these cations might be useful surrogates for E2Eq measurements. Published by Elsevier B.V.

Effect of liquid swine manure rate, incorporation, and timing of rainfall on phosphorus loss with surface runoff.

PubMed

Allen, Brett L; Mallarino, Antonio P

2008-01-01

Excessive manure phosphorus (P) application increases risk of P loss from fields. This study assessed total runoff P (TPR), bioavailable P (BAP), and dissolved reactive P (DRP) concentrations and loads in surface runoff after liquid swine (Sus scrofa domesticus) manure application with or without incorporation into soil and different timing of rainfall. Four replicated manure P treatments were applied in 2002 and in 2003 to two Iowa soils testing low in P managed with corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotations. Total P applied each time was 0 to 80 kg P ha(-1) at one site and 0 to 108 kg P ha(-1) at the other. Simulated rainfall was applied within 24 h of P application or after 10 to 16 d and 5 to 6 mo. Nonincorporated manure P increased DRP, BAP, and TPR concentrations and loads linearly or exponentially for 24-h and 10- to 16-d runoff events. On average for the 24-h events, DRP, BAP, and TPR concentrations were 5.4, 4.7, and 2.2 times higher, respectively, for nonincorporated manure than for incorporated manure; P loads were 3.8, 7.7, and 3.6 times higher; and DRP and BAP concentrations were 54% of TPR for nonincorporated manure and 22 to 25% for incorporated manure. A 10- to 16-d rainfall delay resulted in DRP, BAP, and TPR concentrations that were 3.1, 2.7, and 1.1 times lower, respectively, than for 24-h events across all nonincorporated P rates, sites, and years, whereas runoff P loads were 3.8, 3.6, and 1.6 times lower, respectively. A 5- to 6-mo simulated rainfall delay reduced runoff P to levels similar to control plots. Incorporating swine manure when the probability of immediate rainfall is high reduces the risk of P loss in surface runoff; however, this benefit sharply decreases with time.

Using SMAP to identify structural errors in hydrologic models

NASA Astrophysics Data System (ADS)

Crow, W. T.; Reichle, R. H.; Chen, F.; Xia, Y.; Liu, Q.

2017-12-01

Despite decades of effort, and the development of progressively more complex models, there continues to be underlying uncertainty regarding the representation of basic water and energy balance processes in land surface models. Soil moisture occupies a central conceptual position between atmosphere forcing of the land surface and resulting surface water fluxes. As such, direct observations of soil moisture are potentially of great value for identifying and correcting fundamental structural problems affecting these models. However, to date, this potential has not yet been realized using satellite-based retrieval products. Using soil moisture data sets produced by the NASA Soil Moisture Active/Passive mission, this presentation will explore the use of the remotely-sensed soil moisture data products as a constraint to reject certain types of surface runoff parameterizations within a land surface model. Results will demonstrate that the precision of the SMAP Level 4 Surface and Root-Zone soil moisture product allows for the robust sampling of correlation statistics describing the true strength of the relationship between pre-storm soil moisture and subsequent storm-scale runoff efficiency (i.e., total storm flow divided by total rainfall both in units of depth). For a set of 16 basins located in the South-Central United States, we will use these sampled correlations to demonstrate that so-called "infiltration-excess" runoff parameterizations under predict the importance of pre-storm soil moisture for determining storm-scale runoff efficiency. To conclude, we will discuss prospects for leveraging this insight to improve short-term hydrologic forecasting and additional avenues for SMAP soil moisture products to provide process-level insight for hydrologic modelers.

Remote sensing techniques for prediction of watershed runoff

NASA Technical Reports Server (NTRS)

Blanchard, B. J.

1975-01-01

Hydrologic parameters of watersheds for use in mathematical models and as design criteria for flood detention structures are sometimes difficult to quantify using conventional measuring systems. The advent of remote sensing devices developed in the past decade offers the possibility that watershed characteristics such as vegetative cover, soils, soil moisture, etc., may be quantified rapidly and economically. Experiments with visible and near infrared data from the LANDSAT-1 multispectral scanner indicate a simple technique for calibration of runoff equation coefficients is feasible. The technique was tested on 10 watersheds in the Chickasha area and test results show more accurate runoff coefficients were obtained than with conventional methods. The technique worked equally as well using a dry fall scene. The runoff equation coefficients were then predicted for 22 subwatersheds with flood detention structures. Predicted values were again more accurate than coefficients produced by conventional methods.

Field-calibrated model of melt, refreezing, and runoff for polar ice caps: Application to Devon Ice Cap

NASA Astrophysics Data System (ADS)

Morris, Richard M.; Mair, Douglas W. F.; Nienow, Peter W.; Bell, Christina; Burgess, David O.; Wright, Andrew P.

2014-09-01

Understanding the controls on the amount of surface meltwater that refreezes, rather than becoming runoff, over polar ice masses is necessary for modeling their surface mass balance and ultimately for predicting their future contributions to global sea level change. We present a modified version of a physically based model that includes an energy balance routine and explicit calculation of near-surface meltwater refreezing capacity, to simulate the evolution of near-surface density and temperature profiles across Devon Ice Cap in Arctic Canada. Uniquely, our model is initiated and calibrated using high spatial resolution measurements of snow and firn densities across almost the entire elevation range of the ice cap for the summer of 2004 and subsequently validated with the same type of measurements obtained during the very different meteorological conditions of summer 2006. The model captures the spatial variability across the transect in bulk snowpack properties although it slightly underestimates the flow of meltwater into the firn of previous years. The percentage of meltwater that becomes runoff is similar in both years; however, the spatial pattern of this melt-runoff relationship is different in the 2 years. The model is found to be insensitive to variation in the depth of impermeable layers within the firn but is very sensitive to variation in air temperature, since the refreezing capacity of firn decreases with increasing temperature. We highlight that the sensitivity of the ice cap's surface mass balance to air temperature is itself dependent on air temperature.

Keeping soil in the field - runoff and erosion management in asparagus crops

NASA Astrophysics Data System (ADS)

Niziolomski, Joanna; Simmons, Robert; Rickson, Jane; Hann, Mike

2016-04-01

Row crop production (including potatoes, onions, carrots, asparagus, bulbs and lettuce) is regarded as one of the most erosive agricultural cropping systems. This is a result of the many practices involved that increase erosion risk including: fine seedbed preparation, a typically short growing season where adequate ground cover protects the soil, permanent bare soil areas between crops, and often intensive harvesting methods that can damage soil structure and result in soil compaction. Sustained exposure of bare soil coupled with onsite compaction on slightly sloping land results in soil and water issues in asparagus production. Asparagus production is a growing British industry covering > 2000 ha and is worth approximately £30 million yr-1. However, no tried and tested erosion control measurements currently exist to manage associated problems. Research has recently been undertaken investigating the effectiveness of erosion control measures suitable for asparagus production systems. These consisted of surface applied wheat straw mulch and shallow soil disturbance (< 350 mm) using several tine configurations: a currently adopted winged tine, a narrow with two shallow leading tines, and a modified para-plough. These treatments were tested individually and in combination (straw mulch with each shallow soil disturbance tine configuration) using triplicated field plots situated on a working asparagus farm in Herefordshire, UK. Testing was conducted between May and November 2013. Rainfall-event based runoff and erosion measurements were taken including; runoff volume, runoff rate and total soil loss. Runoff and soil erosion was observed from all treatments. However, the surface application of straw mulch alone out performed each shallow soil disturbance practice. This suggests that runoff and erosion from asparagus production can be reduced using the simple surface application of straw.

Phosphorus runoff from sewage sludge applied to different slopes of lateritic soil.

PubMed

Chen, Yan Hui; Wang, Ming Kuang; Wang, Guo; Chen, Ming Hua; Luo, Dan; Ding, Feng Hua; Li, Rong

2011-01-01

Sewage sludge (SS) applied to sloping fields at rates that exceed annual forest nutrient requirements can be a source of phosphorus (P) in runoff. This study investigates the effects of different slopes (18, 27, 36, and 45%) on P in runoff from plots amended with SS (120 Mg ha). Lateritic soil (pH 5.2) was exposed to five simulated rainfalls (90 mm h) on outdoor plots. When sludge was broadcast and mixed with surface soils, the concentrations and loss in runoff of total P in the mixed sample (MTP), total P in the settled sample (STP), total particulate P (TPP), total suspended P (TSP), and total dissolved P (TDP) were highest at 1 or 18 d after application. Initially, pollution risks to surface waters generally increased to different degrees with steeper slopes, and then diminished gradually with dwindling differences between the slopes. The runoff losses coefficient of MTP increased in the order 36 > 45 > 27 > 18%. The initial event (1 and 18 d) accounted for 67.0 to 83.6% of total runoff P losses. Particulate fraction were dominant carriers for P losses, while with the lower slopes there was higher content of P per unit particulate fraction in runoff. Phosphorus losses were greatly affected by the interaction of sludge-soil-runoff and the modification of soil properties induced by sludge amendment. It is recommended to choose lower slopes (<27%) to reduce risk of P losses. Thus, the risk of application sludge to sloping fields in acid soils should be studied further in the field under a wider diversity of conditions. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Reducing N losses through surface runoff from rice-wheat rotation by improving fertilizer management.

PubMed

Cao, Yansheng; Sun, Huifeng; Liu, Yaqin; Fu, Zishi; Chen, Guifa; Zou, Guoyan; Zhou, Sheng

2017-02-01

To better understand N runoff losses from rice-wheat rotation and demonstrate the effectiveness of improved fertilizer management in reducing N runoff losses, a field study was conducted for three consecutive rice-wheat rotations. Nitrogen losses through surface runoff were measured for five treatments, including CK without N application, C200, C300 simulating the conventional practices, CO200, and CO300. Optimum N rate was applied for C200 and CO200, and 30% of chemical fertilizer was substituted with organic fertilizer for CO200 and CO300 with respect to C200 and C300, respectively. Rice season had higher runoff coefficients than wheat season. Approximately 52% of total N was lost as NH 4 + -N in rice season, ranging from 21 to 83%, and in wheat season, the proportion of NO 3 - -N in total N averaged 53% with a variation from 38 to 67%. The N treatments lost less total N in rice season (1.67-10.7 kg N ha -1 ) than in wheat season (1.72-17.1 kg N ha -1 ). These suggested that a key to controlling N runoff losses from rice-wheat rotation was to limit NO 3 - -N accumulation in wheat season. In both seasons, N runoff losses for C200 and CO300 were lower than those for C300. CO200 better cut N losses than C200 and CO300, with 64 and 57% less N in rice and wheat seasons than C300, respectively. Compared with the conventional practices, optimum N inputs integrated with co-application of organic and chemical fertilizers could reduce N runoff losses with a better N balance under rice-wheat rotation.

Runoff water quality from broiler litter-amended tall fescue in response to natural precipitation in the Ozark Highlands.

PubMed

Menjoulet, B C; Brye, K R; Pirani, A L; Haggard, B E; Gbur, E E

2009-01-01

The Arkansas poultry industry produced more than 1.2 billion broiler chickens (Gallus gallus domesticus) and generated approximately 1.3 million Mg of broiler litter in 2002. High transportation costs of relocating broiler litter have led to annual land applications near poultry houses, increasing concern for potential surface water contamination from runoff. The objective of this study was to evaluate the effect of broiler litter application rate on runoff water quality in response to natural precipitation. Six plots (1.5 by 6.0 m), located on a Captina silt loam (finesilty, siliceous, active, mesic Typic Fragiudult), were amended with fresh broiler litter at 0, 5.6, and 11.2 Mg ha(-1) (control, low, and high litter treatments, respectively) once annually for 4 yr (May 2003 through April 2007). Runoff collected after each runoff-producing event was analyzed for soluble nutrients and metals. Cumulative runoff did not differ among litter treatments over the 4-yr study. At times, flow-weighted mean (FWM) concentrations of As from all litter treatments exceeded the maximum contaminant level for drinking water (0.01 mg As L(-1)). Four-year FWM Fe concentrations and runoff losses were greater (P < 0.05) from the high than from the low litter treatment and unamended control, and the 4-yr FWM P concentration from the low litter treatment (3.0 mg L(-1)) was greater than that from the unamended control (1.8 mg L(-1)). Since precipitation is temporally variable, evaluating runoff water quality in response to natural precipitation over several years is key to ascertaining the long-term impacts of surface-applied soil amendments like broiler litter.

Impacts of the active layer on runoff in an upland permafrost basin, northern Tibetan Plateau

PubMed Central

Zhang, Tingjun; Guo, Hong; Hu, Yuantao; Shang, Jianguo; Zhang, Yulan

2018-01-01

The paucity of studies on permafrost runoff generation processes, especially in mountain permafrost, constrains the understanding of permafrost hydrology and prediction of hydrological responses to permafrost degradation. This study investigated runoff generation processes, in addition to the contribution of summer thaw depth, soil temperature, soil moisture, and precipitation to streamflow in a small upland permafrost basin in the northern Tibetan Plateau. Results indicated that the thawing period and the duration of the zero-curtain were longer in permafrost of the northern Tibetan Plateau than in the Arctic. Limited snowmelt delayed the initiation of surface runoff in the peat permafrost in the study area. The runoff displayed intermittent generation, with the duration of most runoff events lasting less than 24 h. Precipitation without runoff generation was generally correlated with lower soil moisture conditions. Combined analysis suggested runoff generation in this region was controlled by soil temperature, thaw depth, precipitation frequency and amount, and antecedent soil moisture. This study serves as an important baseline to evaluate future environmental changes on the Tibetan Plateau. PMID:29470510

Impacts of the active layer on runoff in an upland permafrost basin, northern Tibetan Plateau.

PubMed

Gao, Tanguang; Zhang, Tingjun; Guo, Hong; Hu, Yuantao; Shang, Jianguo; Zhang, Yulan

2018-01-01

The paucity of studies on permafrost runoff generation processes, especially in mountain permafrost, constrains the understanding of permafrost hydrology and prediction of hydrological responses to permafrost degradation. This study investigated runoff generation processes, in addition to the contribution of summer thaw depth, soil temperature, soil moisture, and precipitation to streamflow in a small upland permafrost basin in the northern Tibetan Plateau. Results indicated that the thawing period and the duration of the zero-curtain were longer in permafrost of the northern Tibetan Plateau than in the Arctic. Limited snowmelt delayed the initiation of surface runoff in the peat permafrost in the study area. The runoff displayed intermittent generation, with the duration of most runoff events lasting less than 24 h. Precipitation without runoff generation was generally correlated with lower soil moisture conditions. Combined analysis suggested runoff generation in this region was controlled by soil temperature, thaw depth, precipitation frequency and amount, and antecedent soil moisture. This study serves as an important baseline to evaluate future environmental changes on the Tibetan Plateau.

A reference data set of hillslope rainfall-runoff response, Panola Mountain Research Watershed, United States

USGS Publications Warehouse

Tromp-van, Meerveld; James, A.L.; McDonnell, Jeffery J.; Peters, N.E.

2008-01-01

Although many hillslope hydrologic investigations have been conducted in different climate, topographic, and geologic settings, subsurface stormflow remains a poorly characterized runoff process. Few, if any, of the existing data sets from these hillslope investigations are available for use by the scientific community for model development and validation or conceptualization of subsurface stormflow. We present a high-resolution spatial and temporal rainfall-runoff data set generated from the Panola Mountain Research Watershed trenched experimental hillslope. The data set includes surface and subsurface (bedrock surface) topographic information and time series of lateral subsurface flow at the trench, rainfall, and subsurface moisture content (distributed soil moisture content and groundwater levels) from January to June 2002. Copyright 2008 by the American Geophysical Union.

Surface coal mine land reclamation using a dry flue gas desulfurization product: Short-term and long-term water responses.

PubMed

Chen, Liming; Stehouwer, Richard; Tong, Xiaogang; Kost, Dave; Bigham, Jerry M; Dick, Warren A

2015-09-01

Abandoned coal-mined lands are a worldwide concern due to their potential negative environmental impacts, including erosion and development of acid mine drainage. A field study investigated the use of a dry flue gas desulfurization product for reclamation of abandoned coal mined land in USA. Treatments included flue gas desulfurization product at a rate of 280 Mg ha(-1) (FGD), FGD at the same rate plus 112 Mg ha(-1) yard waste compost (FGD/C), and conventional reclamation that included 20 cm of re-soil material plus 157 Mg ha(-1) of agricultural limestone (SOIL). A grass-legume sward was planted after treatment applications. Chemical properties of surface runoff and tile water (collected from a depth of 1.2m below the ground surface) were measured over both short-term (1-4 yr) and long-term (14-20 yr) periods following reclamation. The pH of surface runoff water was increased from approximately 3, and then sustained at 7 or higher by all treatments for up to 20 yr, and the pH of tile flow water was also increased and sustained above 5 for 20 yr. Compared with SOIL, concentrations of Ca, S and B in surface runoff and tile flow water were generally increased by the treatments with FGD product in both short- and long-term measurements and concentrations of the trace elements were generally not statistically increased in surface runoff and tile flow water over the 20-yr period. However, concentrations of As, Ba, Cr and Hg were occasionally elevated. These results suggest the use of FGD product for remediating acidic surface coal mined sites can provide effective, long-term reclamation. Copyright © 2015. Published by Elsevier Ltd.

Narrow grass hedges reduce tylosin and associated antimicrobial resistance genes in agricultural runoff

USDA-ARS?s Scientific Manuscript database

Agricultural runoff from areas receiving livestock manure can potentially contaminate surface water with antimicrobials and antimicrobial resistance genes (ARGs). The objective of this study was to investigate the effectiveness of narrow grass hedges (NGHs) on reducing the transport of antimicrobial...

Low input verses traditional turfgrass: Comparing runoff quantity and quality

USDA-ARS?s Scientific Manuscript database

Strategies used to maintain managed biological systems, including golf course turf, often involve application of fertilizer and pesticides to optimize plant health and protection. The transport of applied chemicals with runoff to surrounding surface waters has been shown to result in enhanced algal ...

Assessment of copper removal from highway stormwater runoff using Apatite II(TM) and compost : laboratory and field testing.

DOT National Transportation Integrated Search

2015-03-01

-Stormwater runoff introduces heavy metals to surface waters that are harmful to aquatic organisms, : including endangered salmon. This work evaluates Apatite II, a biogenic fish bone based adsorbent, for removing metal : from stormwater. The meta...

Metal and nutrient dynamics on an aged intensive green roof.

PubMed

Speak, A F; Rothwell, J J; Lindley, S J; Smith, C L

2014-01-01

Runoff and rainfall quality was compared between an aged intensive green roof and an adjacent conventional roof surface. Nutrient concentrations in the runoff were generally below Environmental Quality Standard (EQS) values and the green roof exhibited NO3(-) retention. Cu, Pb and Zn concentrations were in excess of EQS values for the protection of surface water. Green roof runoff was also significantly higher in Fe and Pb than on the bare roof and in rainfall. Input-output fluxes revealed the green roof to be a potential source of Pb. High concentrations of Pb within the green roof soil and bare roof dusts provide a potential source of Pb in runoff. The origin of the Pb is likely from historic urban atmospheric deposition. Aged green roofs may therefore act as a source of legacy metal pollution. This needs to be considered when constructing green roofs with the aim of improving pollution remediation. Copyright © 2013 Elsevier Ltd. All rights reserved.

A preliminary assessment of water partitioning and ecohydrological coupling in northern headwaters using stable isotopes and conceptual runoff models

PubMed Central

Buttle, James; Carey, Sean K.; van Huijgevoort, Marjolein H. J.; Laudon, Hjalmar; McNamara, James P.; Mitchell, Carl P. J.; Spence, Chris; Gabor, Rachel S.; Soulsby, Chris

2015-01-01

Abstract We combined a conceptual rainfall‐runoff model and input–output relationships of stable isotopes to understand ecohydrological influences on hydrological partitioning in snow‐influenced northern catchments. Six sites in Sweden (Krycklan), Canada (Wolf Creek; Baker Creek; Dorset), Scotland (Girnock) and the USA (Dry Creek) span moisture and energy gradients found at high latitudes. A meta‐analysis was carried out using the Hydrologiska Byråns Vattenbalansavdelning (HBV) model to estimate the main storage changes characterizing annual water balances. Annual snowpack storage importance was ranked as Wolf Creek > Krycklan > Dorset > Baker Creek > Dry Creek > Girnock. The subsequent rate and longevity of melt were reflected in calibrated parameters that determine partitioning of waters between more rapid and slower flowpaths and associated variations in soil and groundwater storage. Variability of stream water isotopic composition depends on the following: (i) rate and duration of spring snowmelt; (ii) significance of summer/autumn rainfall; and (iii) relative importance of near‐surface and deeper flowpaths in routing water to the stream. Flowpath partitioning also regulates influences of summer evaporation on drainage waters. Deviations of isotope data from the Global Meteoric Water Line showed subtle effects of internal catchment processes on isotopic fractionation most likely through evaporation. Such effects are highly variable among sites and with seasonal differences at some sites. After accounting for climate, evaporative fractionation is strongest at sites where lakes and near‐surface runoff processes in wet riparian soils can mobilize isotopically enriched water during summer and autumn. Given close soil–vegetation coupling, this may result in spatial variability in soil water isotope pools available for plant uptake. We argue that stable isotope studies are crucial in addressing the many open questions on hydrological functioning of northern environments. © 2015 The Authors. Hydrological Processes published by John Wiley & Sons Ltd. PMID:27656040

Future flood risk in the tropics as measured by changes in extreme runoff intensity is strongly influenced by plant-physiological responses to rising CO2

NASA Astrophysics Data System (ADS)

Kooperman, G. J.; Hoffman, F. M.; Koven, C.; Lindsay, K. T.; Swann, A. L. S.; Randerson, J. T.

2017-12-01

Climate change is expected to increase the frequency of intense flooding events, and thus the risk of flood-related mortality, infrastructure damage, and economic loss. Assessments of future flooding from global climate models based only on precipitation intensity and temperature neglect important processes that occur within the land-surface, particularly the impacts of plant-physiological responses to rising CO2. Higher CO2 reduces stomatal conductance, leading to less water loss through transpiration and higher soil moisture. For a given precipitation rate, higher soil moisture decreases the amount of rainwater that infiltrates the surface and increases runoff. Here we assess the relative impacts of plant-physiological and radiative-greenhouse effects on changes in extreme runoff intensity over tropical continents using the Community Earth System Model. We find that extreme percentile rates increase significantly more than mean runoff in response to higher CO2. Plant-physiological effects contribute to only a small increase in precipitation intensity, but are a dominant driver of runoff intensification, contributing to one-half of the 99th percentile runoff intensity change and one-third of the 99.9th percentile change. Comprehensive assessments of future flooding risk need to account for the physiological as well as radiative impacts of CO2 in order to better inform flood prediction and mitigation practices.

A mathematical model for soil solute transfer into surface runoff as influenced by rainfall detachment.

PubMed

Yang, Ting; Wang, Quanjiu; Wu, Laosheng; Zhao, Guangxu; Liu, Yanli; Zhang, Pengyu

2016-07-01

Nutrients transport is a main source of water pollution. Several models describing transport of soil nutrients such as potassium, phosphate and nitrate in runoff water have been developed. The objectives of this research were to describe the nutrients transport processes by considering the effect of rainfall detachment, and to evaluate the factors that have greatest influence on nutrients transport into runoff. In this study, an existing mass-conservation equation and rainfall detachment process were combined and augmented to predict runoff of nutrients in surface water in a Loess Plateau soil in Northwestern Yangling, China. The mixing depth is a function of time as a result of rainfall impact, not a constant as described in previous models. The new model was tested using two different sub-models of complete-mixing and incomplete-mixing. The complete-mixing model is more popular to use for its simplicity. It captured the runoff trends of those high adsorption nutrients, and of nutrients transport along steep slopes. While the incomplete-mixing model predicted well for the highest observed concentrations of the test nutrients. Parameters inversely estimated by the models were applied to simulate nutrients transport, results suggested that both models can be adopted to describe nutrients transport in runoff under the impact of rainfall. Copyright © 2016 Elsevier B.V. All rights reserved.

Permeability predictions for sand-clogged Portland cement pervious concrete pavement systems.

PubMed

Haselbach, Liv M; Valavala, Srinivas; Montes, Felipe

2006-10-01

Pervious concrete is an alternative paving surface that can be used to reduce the nonpoint source pollution effects of stormwater runoff from paved surfaces such as roadways and parking lots by allowing some of the rainfall to permeate into the ground below. This infiltration rate may be adversely affected by clogging of the system, particularly clogging or covering by sand in coastal areas. A theoretical relation was developed between the effective permeability of a sand-clogged pervious concrete block, the permeability of sand, and the porosity of the unclogged block. Permeabilities were then measured for Portland cement pervious concrete systems fully covered with extra fine sand in a flume using simulated rainfalls. The experimental results correlated well with the theoretical calculated permeability of the pervious concrete system for pervious concrete systems fully covered on the surface with sand. Two different slopes (2% and 10%) were used. Rainfall rates were simulated for the combination of direct rainfall (passive runoff) and for additional stormwater runoff from adjacent areas (active runoff). A typical pervious concrete block will allow water to pass through at flow rates greater than 0.2 cm/s and a typical extra fine sand will have a permeability of approximately 0.02 cm/s. The limit of the system with complete sand coverage resulted in an effective system permeability of approximately 0.004 cm/s which is similar to the rainfall intensity of a 30 min duration, 100-year frequency event in the southeastern United States. The results obtained are important in designing and evaluating pervious concrete as a paving surface within watershed management systems for controlling the quantity of runoff.

Hydroclimatic regimes: a distributed water-balance framework for hydrologic assessment, classification, and management

USGS Publications Warehouse

Weiskel, Peter K.; Wolock, David M.; Zarriello, Phillip J.; Vogel, Richard M.; Levin, Sara B.; Lent, Robert M.

2014-01-01

Runoff-based indicators of terrestrial water availability are appropriate for humid regions, but have tended to limit our basic hydrologic understanding of drylands – the dry-subhumid, semiarid, and arid regions which presently cover nearly half of the global land surface. In response, we introduce an indicator framework that gives equal weight to humid and dryland regions, accounting fully for both vertical (precipitation + evapotranspiration) and horizontal (groundwater + surface-water) components of the hydrologic cycle in any given location – as well as fluxes into and out of landscape storage. We apply the framework to a diverse hydroclimatic region (the conterminous USA) using a distributed water-balance model consisting of 53 400 networked landscape hydrologic units. Our model simulations indicate that about 21% of the conterminous USA either generated no runoff or consumed runoff from upgradient sources on a mean-annual basis during the 20th century. Vertical fluxes exceeded horizontal fluxes across 76% of the conterminous area. Long-term-average total water availability (TWA) during the 20th century, defined here as the total influx to a landscape hydrologic unit from precipitation, groundwater, and surface water, varied spatially by about 400 000-fold, a range of variation ~100 times larger than that for mean-annual runoff across the same area. The framework includes but is not limited to classical, runoff-based approaches to water-resource assessment. It also incorporates and reinterprets the green- and blue-water perspective now gaining international acceptance. Implications of the new framework for several areas of contemporary hydrology are explored, and the data requirements of the approach are discussed in relation to the increasing availability of gridded global climate, land-surface, and hydrologic data sets.

Emergence of new hydrologic regimes of surface water resources in the conterminous United States under future warming

NASA Astrophysics Data System (ADS)

Leng, Guoyong; Huang, Maoyi; Voisin, Nathalie; Zhang, Xuesong; Asrar, Ghassem R.; Leung, L. Ruby

2016-11-01

Despite the importance of surface water to people and ecosystems, few studies have explored detectable changes in surface water supply in a changing climate, given its large natural variability. Here we analyze runoff projections from the Variable Infiltration Capacity hydrological model driven by 97 downscaled and bias-corrected Coupled Model Intercomparison Project Phase 5 climate projections over the conterminous United States (CONUS). Our results show that more than 40% of the CONUS land area will experience significant changes in the probability distribution functions (i.e. PDFs) of summer and winter runoff by the end of the 21st century, which may pose great challenges to future surface water supply. Sub-basin mean runoff PDFs are projected to change significantly after 2040s depending on the emission scenarios, with earliest occurrence in the Pacific Northwest and northern California regions. When examining the response as a function of changes in the global mean temperature (ΔGMT), a linear relationship is revealed at the 95% confidence level. Generally, 1 °C increase of GMT leads to 11% and 17% more lands experiencing changes in summer and winter runoff PDFs, respectively. Such changes in land fraction scale with ΔGMT at the country scale independent of emission scenarios, but the same relationship does not necessarily hold at sub-basin scales, due to the larger role of atmospheric circulation changes and their uncertainties on regional precipitation. Further analyses show that the emergence of significant changes in sub-basin runoff PDFs is indicative of the emergence of new hydrology regimes and it is dominated by the changes in variability rather than shift in the mean, regardless of the emission scenarios.

Influence of aeration implements, phosphorus fertilizers, and soil taxa on phosphorus losses from grasslands.

PubMed

Franklin, D H; Butler, D M; Cabrera, M L; Calvert, V H; West, L T; Rema, J A

2011-01-01

Attenuation of rainfall within the solum may help to move contaminants and nutrients into the soil to be better sequestered or utilized by crops. Surface application of phosphorus (P) amendments to grasslands may lead to elevated concentrations of P in surface runoff and eutrophication of surface waters. Aeration of grasslands has been proposed as a treatment to reduce losses of applied P. Here, results from two small-plot aeration studies and two field-scale, paired-watershed studies are supplemented with previously unpublished soil P data and synthesized. The overall objective of these studies was to determine the impact of aeration on soil P, runoff volume, and runoff P losses from mixed tall fescue [Lolium arundinaceum (Schreb.) Darbysh.]-bermudagrass (Cynodon dactylon L.) grasslands fertilized with P. Small-scale rainfall simulations were conducted on two soil taxa using three types of aeration implements: spikes, disks, and cores. The-field scale study was conducted on four soil taxa with slit and knife aeration. Small-plot studies showed that core aeration reduced loads of total P and dissolved reactive P (DRP) in runoff from plots fertilized with broiler litter and that aeration was effective in reducing P export when it increased soil P in the upper 5 cm. In the field-scale study, slit aeration reduced DRP losses by 35% in fields with well-drained soils but not in poorly drained soils. Flow-weighted concentrations of DRP in aerated fields were related to water-soluble P applied in amendments and soil test P in the upper 5 cm. These studies show that the overall effectiveness of mechanical soil aeration on runoff volume and P losses is controlled by the interaction of soil characteristics such as internal drainage and compaction, soil P, type of surface-applied manure, and type of aeration implement.

Hydrological Response of Semi-arid Degraded Catchments in Tigray, Northern Ethiopia

NASA Astrophysics Data System (ADS)

Teka, Daniel; Van Wesemael, Bas; Vanacker, Veerle; Hallet, Vincent

2013-04-01

To address water scarcity in the arid and semi-arid part of developing countries, accurate estimation of surface runoff is an essential task. In semi-arid catchments runoff data are scarce and therefore runoff estimation using hydrological models becomes an alternative. This research was initiated in order to characterize runoff response of semi-arid catchments in Tigray, North Ethiopia to evaluate SCS-CN for various catchments. Ten sub-catchments were selected in different river basins and rainfall and runoff were measured with automatic hydro-monitoring equipments for 2-3 years. The Curve Number was estimated for each Hydrological Response Unit (HRU) in the sub-catchments and runoff was modeled using the SCS-CN method at λ = 0.05 and λ = 0.20. The result showed a significant difference between the two abstraction ratios (P =0.05, df = 1, n= 132) and reasonable good result was obtained for predicted runoff at λ = 0.05 (NSE = -0.69; PBIAS = 18.1%). When using the CN values from literature runoff was overestimated compared to the measured value (e= -11.53). This research showed the importance of using measured runoff data to characterize semi-arid catchments and accurately estimate the scarce water resource. Key words: Hydrological response, rainfall-runoff, degraded environments, semi-arid, Ethiopia, Tigray

The effect of poultry manure application rate and AlCl(3) treatment on bacterial fecal indicators in runoff.

PubMed

Brooks, J P; Adeli, A; McLaughlin, M R; Miles, D M

2012-12-01

Increasing costs associated with inorganic fertilizer have led to widespread use of broiler litter. Proper land application, typically limiting nutrient loss, is essential to protect surface water. This study was designed to evaluate litter-borne microbial runoff (heterotrophic plate count bacteria, staphylococci, Escherichia coli, enterococci, and Clostridium perfringens) while applying typical nutrient-control methods. Field studies were conducted in which plots with high and low litter rates, inorganic fertilizer, AlCl(3)-treated litter, and controls were rained on five times using a rain generator. Overall, microbial runoff from poultry litter applied plots was consistently greater (2-5 log(10) plot(-1)) than controls. No appreciable effect on microbial runoff was noted from variable litter application rate or AlCl(3) treatments, though rain event, not time, significantly affected runoff load. C. perfringens and staphylococci runoff were consistently associated with poultry litter application, during early rain events, while other indicators were unreliable. Large microbial runoff pulses were observed, ranging from 10(2) to 10(10) CFU plot(-1); however, only a small fraction of litter-borne microbes were recoverable in runoff. This study indicated that microbial runoff from litter-applied plots can be substantial, and that methods intended to reduce nutrient losses do not necessarily reduce microbial runoff.

Green roof stormwater retention: effects of roof surface, slope, and media depth.

PubMed

VanWoert, Nicholaus D; Rowe, D Bradley; Andresen, Jeffrey A; Rugh, Clayton L; Fernandez, R Thomas; Xiao, Lan

2005-01-01

Urban areas generate considerably more stormwater runoff than natural areas of the same size due to a greater percentage of impervious surfaces that impede water infiltration. Roof surfaces account for a large portion of this impervious cover. Establishing vegetation on rooftops, known as green roofs, is one method of recovering lost green space that can aid in mitigating stormwater runoff. Two studies were performed using several roof platforms to quantify the effects of various treatments on stormwater retention. The first study used three different roof surface treatments to quantify differences in stormwater retention of a standard commercial roof with gravel ballast, an extensive green roof system without vegetation, and a typical extensive green roof with vegetation. Overall, mean percent rainfall retention ranged from 48.7% (gravel) to 82.8% (vegetated). The second study tested the influence of roof slope (2 and 6.5%) and green roof media depth (2.5, 4.0, and 6.0 cm) on stormwater retention. For all combined rain events, platforms at 2% slope with a 4-cm media depth had the greatest mean retention, 87%, although the difference from the other treatments was minimal. The combination of reduced slope and deeper media clearly reduced the total quantity of runoff. For both studies, vegetated green roof systems not only reduced the amount of stormwater runoff, they also extended its duration over a period of time beyond the actual rain event.

The measurement of dry deposition and surface runoff to quantify urban road pollution in Taipei, Taiwan.

PubMed

Wang, Yunn-Jinn; Chen, Chi-Feng; Lin, Jen-Yang

2013-10-16

Pollutants deposited on road surfaces and distributed in the environment are a source of nonpoint pollution. Field data are traditionally hard to collect from roads because of constant traffic. In this study, in cooperation with the traffic administration, the dry deposition on and road runoff from urban roads was measured in Taipei City and New Taipei City, Taiwan. The results showed that the dry deposition is 2.01-5.14 g/m(2) · day and 78-87% of these solids are in the 75-300 µm size range. The heavy metals in the dry deposited particles are mainly Fe, Zn, and Na, with average concentrations of 34,978, 1,519 and 1,502 ppm, respectively. Elevated express roads show the highest heavy metal concentrations. Not only the number of vehicles, but also the speed of the traffic should be considered as factors that influence road pollution, as high speeds may accelerate vehicle wear and deposit more heavy metals on road surfaces. In addition to dry deposition, the runoff and water quality was analyzed every five minutes during the first two hours of storm events to capture the properties of the first flush road runoff. The sample mean concentration (SMC) from three roads demonstrated that the first flush runoff had a high pollution content, notably for suspended solid (SS), chemical oxygen demand (COD), oil and grease, Pb, and Zn. Regular sweeping and onsite water treatment facilities are suggested to minimize the pollution from urban roads.

Temporal evolution of water repellency and preferential flow in the post-fire

NASA Astrophysics Data System (ADS)

Alanís, Nancy; Jordán, Antonio; Zavala, Lorena M.

2015-04-01

Forest fires usually intensify erosive process due to the reduction of vegetation cover and degradation of aggregation in the topsoil. Another common effect of wildifres is the development of soil water repellency, which in turn favors the formation of runoff, inhibiting or delaying infiltration. Under these conditions, infiltration occurs only when ponded water or runoff flow finds macropores and cracks in the soil surface, producing preferential flow pathways. When water infiltrates through these paths, a significant portion of the soil remains dry, limiting the supply of nutrients to the roots, favoring the rapid leaching of nutrients and agrochemicals, and other impacts on flora and hydrological processes at hillslope- or basin-scale. The existence of irregular wetting fronts has been observed frequently in burned or unburned water repellent soils. Although some authors have suggested that preferential flow paths may be more or less permanent in the case of unburned soils, the temporal evolution of preferential flow has been rarely studied in burned soils during the post-fire, after water repellency decreases or disappears. This research focuses on the temporal evolution of water repellency and preferential flows in an area affected by fire.

Spectral Measurement of Watershed Coefficients in the Southern Great Plains

NASA Technical Reports Server (NTRS)

Blanchard, B. J. (Principal Investigator); Bausch, W.

1978-01-01

The author has identified the following significant results. It was apparent that the spectra calibration of runoff curve numbers cannot be achieved on watersheds where significant areas of timber were within the drainage area. The absorption of light by wet soil conditions restricts differentiation of watersheds with regard to watershed runoff curve numbers. It appeared that the predominant factor influencing the classification of watershed runoff curve numbers was the difference in soil color and its associated reflectance when dry. In regions where vegetation grown throughout the year, where wet surface conditions prevail or where watersheds are timbered, there is little hope of classifying runoff potential with visible light alone.

Effects of combined application of organic and inorganic fertilizers plus nitrification inhibitor DMPP on nitrogen runoff loss in vegetable soils.

PubMed

Yu, Qiaogang; Ma, Junwei; Zou, Ping; Lin, Hui; Sun, Wanchun; Yin, Jianzhen; Fu, Jianrong

2015-01-01

The application of nitrogen fertilizers leads to various ecological problems such as large amounts of nitrogen runoff loss causing water body eutrophication. The proposal that nitrification inhibitors could be used as nitrogen runoff loss retardants has been suggested in many countries. In this study, simulated artificial rainfall was used to illustrate the effect of the nitrification inhibitor DMPP (3,4-dimethyl pyrazole phosphate) on nitrogen loss from vegetable fields under combined organic and inorganic nitrogen fertilizer application. The results showed that during the three-time simulated artificial rainfall period, the ammonium nitrogen content in the surface runoff water collected from the DMPP application treatment increased by 1.05, 1.13, and 1.10 times compared to regular organic and inorganic combined fertilization treatment, respectively. In the organic and inorganic combined fertilization with DMPP addition treatment, the nitrate nitrogen content decreased by 38.8, 43.0, and 30.1% in the three simulated artificial rainfall runoff water, respectively. Besides, the nitrite nitrogen content decreased by 95.4, 96.7, and 94.1% in the three-time simulated artificial rainfall runoff water, respectively. A robust decline in the nitrate and nitrite nitrogen surface runoff loss could be observed in the treatments after the DMPP addition. The nitrite nitrogen in DMPP addition treatment exhibited a significant low level, which is near to the no fertilizer application treatment. Compared to only organic and inorganic combined fertilizer treatment, the total inorganic nitrogen runoff loss declined by 22.0 to 45.3% in the organic and inorganic combined fertilizers with DMPP addition treatment. Therefore, DMPP could be used as an effective nitrification inhibitor to control the soil ammonium oxidation in agriculture and decline the nitrogen runoff loss, minimizing the nitrogen transformation risk to the water body and being beneficial for the ecological environment.

Transport of Three Antimicrobials in Runoff from Windrows of Composting Beef Cattle Manure.

PubMed

Sura, Srinivas; Degenhardt, Dani; Cessna, Allan J; Larney, Francis J; Olson, Andrew F; McAllister, Tim A

2016-03-01

Rain runoff from windrowed or stockpiled manure may contain antimicrobials with the potential to contaminate surface and ground water. To quantify the concentration of antimicrobials transported in runoff from windrowed manure, antimicrobials were administered continuously in feed to beef cattle () as follows: 44 mg of chlortetracycline kg feed (dry weight), a 1:1 mixture of 44 mg of chlortetracycline and 44 mg sulfamethazine kg feed, and 11 mg of tylosin kg feed. Cattle in a fourth treatment group received no antimicrobials (control). Manure from the cattle was used to construct two windrows per treatment. On Days 2 and 21 of composting, a portable Guelph Rainfall Simulator II was used to apply deionized water at an intensity of 127 mm h to each windrow, and the runoff was collected. Manure samples were collected before rain simulations on Days 2 and 21 of composting for antimicrobial analysis. On Day 2, average concentrations of chlortetracycline, sulfamethazine, and tylosin in manure were 2580, 450, and 120 μg kg, respectively, with maximum concentrations in runoff of 2740, 3600, and 4930 μg L, respectively. Concentrations of all three antimicrobials in runoff were higher ( < 0.05) on Day 2 than on Day 21, reflecting the higher concentrations in manure on Day 2. Maximum estimated masses of chlortetracycline, sulfamethazine, and tylosin that could be transported in runoff from a windrow (3 m long, 2.5 m wide, 1.5 m high) were approximately 0.87 to 0.94, 1.57, and 1.23 g, respectively. This study demonstrates the importance of windrow composting in reducing antimicrobial concentrations in manure. The runoff from windrows can be a source of antimicrobials and demonstrates the need for containment of runoff from composting facilities to mitigate antimicrobial contamination of surface and groundwater resources. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Performance of compost filtration practice for green infrastructure stormwater applications.

PubMed

Faucette, Britt; Cardoso, Fatima; Mulbry, Walter; Millner, Pat

2013-09-01

Urban storm water runoff poses a substantial threat of pollution to receiving surface waters. Green infrastructure, low impact development, green building ordinances, National Pollutant Discharge Elimination System (NPDES) storm water permit compliance, and Total Maximum Daily Load (TMDL) implementation strategies have become national priorities; however, designers need more sustainable, low-cost solutions to meet these goals and guidelines. The objective of this study was to determine the multiple-event removal efficiency and capacity of compost filter socks (FS) and filter socks with natural sorbents (NS) to remove soluble phosphorus, ammonium-nitrogen, nitrate-nitrogen, E. coli, Enterococcus, and oil from urban storm water runoff. Treatments were exposed to simulated storm water pollutant concentrations consistent with urban runoff originating from impervious surfaces, such as parking lots and roadways. Treatments were exposed to a maximum of 25 runoff events, or when removal efficiencies were < or = 25%, whichever occurred first. Experiments were conducted in triplicate. The filter socks with natural sorbents removed significantly greater soluble phosphorus than the filter socks alone, removing a total of 237 mg/linear m over eight runoff events, or an average of 34%. The filter socks with natural sorbents removed 54% of ammonium-nitrogen over 25 runoff events, or 533 mg/linear m, and only 11% of nitrate-nitrogen, or 228 mg/linear m. The filter socks and filter socks with natural sorbents both removed 99% of oil over 25 runoff events, or a total load of 38,486 mg/linear m. Over 25 runoff events the filter socks with natural sorbents removed E. coli and Enteroccocus at 85% and 65%, or a total load of 3.14 CFUs x 10(8)/ linear m and 1.5 CFUs x 10(9)/linear m, respectively; both were significantly greater than treatment by filter socks alone. Based on these experiments, this technique can be used to reduce soluble pollutants from storm water over multiple runoff events.

Regression Techniques for Determining the Effective Impervious Area in Southern California Watersheds

NASA Astrophysics Data System (ADS)

Sultana, R.; Mroczek, M.; Dallman, S.; Sengupta, A.; Stein, E. D.

2016-12-01

The portion of the Total Impervious Area (TIA) that is hydraulically connected to the storm drainage network is called the Effective Impervious Area (EIA). The remaining fraction of impervious area, called the non-effective impervious area, drains onto pervious surfaces which do not contribute to runoff for smaller events. Using the TIA instead of EIA in models and calculations can lead to overestimates of runoff volumes peak discharges and oversizing of drainage system since it is assumed all impervious areas produce urban runoff that is directly connected to storm drains. This makes EIA a better predictor of actual runoff from urban catchments for hydraulic design of storm drain systems and modeling non-point source pollution. Compared to TIA, determining the EIA is considerably more difficult to calculate since it cannot be found by using remote sensing techniques, readily available EIA datasets, or aerial imagery interpretation alone. For this study, EIA percentages were calculated by two successive regression methods for five watersheds (with areas of 8.38 - 158mi2) located in Southern California using rainfall-runoff event data for the years 2004 - 2007. Runoff generated from the smaller storm events are considered to be emanating only from the effective impervious areas. Therefore, larger events that were considered to have runoff from both impervious and pervious surfaces were successively removed in the regression methods using a criterion of (1) 1mm and (2) a max (2 , 1mm) above the regression line. MSE is calculated from actual runoff and runoff predicted by the regression. Analysis of standard deviations showed that criterion of max (2 , 1mm) better fit the regression line and is the preferred method in predicting the EIA percentage. The estimated EIAs have shown to be approximately 78% to 43% of the TIA which shows use of EIA instead of TIA can have significant impact on the cost building urban hydraulic systems and stormwater capture devices.

Competing feedbacks drive state transitions during initial catchment evolution: Examples from post-mining landscape and ecosystems evolution

NASA Astrophysics Data System (ADS)

Hinz, Christoph; Wolfgang, Schaaf; Werner, Gerwin

2014-05-01

Within the context of severely disturbed landscapes with little or no ecological memory, such as post-mining landscapes, we propose a simple framework that explains the catchment evolution as a result of competing feedbacks influenced by the initial conditions and the atmospheric drivers such as rainfall intermittency and intensity. The first stage of the evolution is dominated by abiotic feedbacks triggered by rainfall and subsequent fluid flow causing particle mobilisation on the surface and in the subsurface leading to flow concentration or in some instances to densification of surface and subsurface substrates. Subsequently, abiotic-biotic feedbacks start to compete in the sense that biological activity generally stabilizes substrate by preventing particle mobilisation and hence contribute to converting the substrate to a habitat. We suggest that these competing feedbacks may generate alternative stable states in particular under semi-arid and arid climatic conditions, while in temperate often energy limited environments biological process "outcompete" abiotic processes leading to a stable state, in particular from the water balance point of view for comparable geomorphic situations. To illustrate this framework, we provide examples from post-mining landscapes, in which soil, water and vegetation was monitored. In case of arid regions in Australia, we provide evidence that the initial conditions of a mine waste disposal "locked" the system into a state that was limited by water and nutrient storage capacity while at the same time it was stable from a geomorphic point of view for the observation period. The cause of the system to be locked in, is the very high hydraulic conductivity of the substrate, that has not undergone any changes during the first years. In contrast to this case study, we illustrate how this framework explains the evolution of an artificial catchment (Hühnerwasser Catchment) in Lusatia (150 km southeast of Berlin, Germany). During the initial phase of development the catchment changed very rapidly due to sediment transport, drainage network formation, and soil crusting very similar to geomorphic processes observed in arid and semi-arid landscapes void of dense vegetation. Hydraulic properties changed rapidly after few wet and dry cycles, indicative of particle mobilisation and trapping in the subsurface. Accordingly, the hydrological regime was controlled by rapid surface runoff enhanced through crust formation and at the same time a shallow ground water system developed. This surface runoff regime peeked about two years initialisation as shown by a maximum area of drainage channels. A major, fairly rapid transition occurred between three and five years after placement, in which the sediment transport ceased and vegetation coverage of the drainage channel exceeded 90%. The transition represents the onset of a transpiration dominated regime that is further enhanced by change of the plant composition of the vegetation with tree recruitment from the surrounding forming significant clusters in the catchment. This transition in the third year was also seen in a significant increase in soil fauna and plant diversity.

Simulation of rainfall-runoff response in mined and unmined watersheds in coal areas of West Virginia

USGS Publications Warehouse

Puente, Celso; Atkins, John T.

1989-01-01

Meteorologic and hydrologic data from five small watersheds in the coal areas of West Virginia were used to calibrate and test the U.S. Geological Survey Precipitation-Runoff Modeling System for simulating streamflow under various climatic and land-use conditions. Three of the basins--Horsecamp Run, Gilmer Run, and Collison Creek--are primarily forested and relatively undisturbed. The remaining basins--Drawdy Creek and Brier Creek-are extensively mined, both surface and underground above stream drainage level. Low-flow measurements at numerous synoptic sites in the mined basins indicate that coal mining has substantially altered the hydrologic system of each basin. The effects of mining on streamflow that were identified are (1) reduced base flow in stream segments underlain by underground mines, (2) increased base flow in streams that are downdip and stratigraphically below the elevation of the mined coal beds, and (3) interbasin transfer of ground water through underground mines. These changes probably reflect increased permeability of surface rocks caused by subsidence fractures associated with collapsed underground mines in the basin. Such fractures would increase downward percolation of precipitation, surface and subsurface flow, and ground-water flow to deeper rocks or to underground mine workings. Model simulations of the water budgets for the unmined basins during the 1972-73 water years indicate that total annual runoff averaged 60 percent of average annual precipitation; annual evapotranspiration losses averaged 40 percent of average annual precipitation. Of the total annual runoff, approximately 91 percent was surface and subsurface runoff and 9 percent was groundwater discharge. Changes in storage in the soil zone and in the subsurface and ground-water reservoirs in the basins were negligible. In contrast, water-budget simulations for the mined basins indicate significant differences in annual recharge and in total annual runoff. Model simulations of the water budget for Drawdy Creek basin indicate that total annual runoff during 1972-73 averaged only 43 percent of average annual precipitation--the lowest of all study basins; annual evapotranspiration losses averaged 49 percent, and interbasin transfer of ground-water losses averaged about 8 percent. Of the total annual runoff, approximately 74 percent was surface and subsurface flow and 26 percent was ground-water discharge. The low total annual runoff at Drawdy Creek probably reflects increased recharge of precipitation and surface and subsurface flow losses to ground water. Most of the increase in ground-water storage is, in turn, lost to a ground-water sink--namely, interbasin transfer of ground water by gravity drainage and (or) mine pumpage from underground mines that extend to adjacent basins. Hypothetical mining situations were posed for model analysis to determine the effects of increased mining on streamflow in the mined basins. Results of model simulations indicate that streamflow characteristics, the water budget, and the seasonal distribution of streamflow would be significantly modified in response to an increase in mining in the basins. Simulations indicate that (1) total annual runoff in the basins would decrease because of increased surface- and subsurface-flow losses and increased recharge of precipitation to ground water (these losses would tend to reduce medium to high flows mainly during winter and spring when losses would be greatest), (2) extreme high flows in response to intense rainstorms would be negligibly affected, regardless of the magnitude of mining in the basins, (3) ground-water discharge also would decrease during winter and spring, but the amount and duration of low flows during summer and fall would substantially increase in response to increased ground-water storage in rocks and in underground mines, and (4) the increase in ground-water storage in the basins would be depleted, mostly by increased losses to a grou

Relation of urban land-use and land-surface characteristics to quantity and quality of storm runoff in two basins in California

USGS Publications Warehouse

Sylvester, Marc A.; Brown, William M.

1978-01-01

Two basins (Castro Valley Creek, in Alameda County, and Strong Ranch Slough, in Sacramento County) in the San Francisco Bay and Sacramento-San Joaquin Delta region (Bay-Delta region) were sampled intensively (3-15 minute intervals) during three storms between October 1974 and April 1975. Both basins are primarily residential, but the Strong Ranch Slough basin is almost entirely urbanized and nearly flat, while the Castro Valley Creek basin possesses some rural areas and slopes greater than 70 percent in the headwaters. Water discharge and concentrations of suspended solids, chemical oxygen demand, 5-day biochemical oxygen demand, nitrite and nitrate, total Kjeldahl nitrogen, total orthophosphorus, and settleable matter were usually greater at the Castro Valley Creek basin than at the Strong Ranch Slough basin. Concentrations of these constituents and water discharge changed more rapidly at the Castro Valley Creek basin than at the Strong Ranch Slough basin. Of the four subbasins sampled (two in each basin), constituent concentrations in runoff from a residential subbasin were usually greatest. Quantity and quality of runoff were related to environmental characteristics such as slope, perviousness, residential development and maintenance, and channel conditions. Greater water discharge and concentrations of constituents in the Castro Valley Creek basin seem to be partly due to steeper slopes, less perviousness, and smaller residential lot sizes than are in the Strong Ranch Slough basin. Erosion of steep slopes disturbed by grazing and residential development, poorly maintained dwellings and lots, and a mostly earthen drainage channel in the Castro Valley Creek basin are probably responsible for the greater concentrations of suspended solids and settleable matter in runoff from this basin. In both basins, the highest observed concentrations of suspended solids, chemical oxygen demand, 5-day biochemical oxygen demand, settleable matter, total Kjeldahl nitrogen, and total orthophosphorus were observed at or near peak water discharges. Flow-weighted and arithmetic-mean concentrations of suspended solids in Castro Valley Creek exceed the arithmetic-mean concentration of suspended solids in medium-strength untreated sewage. These results indicate that control of urban storm runoff in the Bay-Delta region may be desirable to protect receiving water.

Atmospheric mercury accumulation and washoff processes on impervious urban surfaces

USGS Publications Warehouse

Eckley, C.S.; Branfireun, B.; Diamond, M.; Van Metre, P.C.; Heitmuller, F.

2008-01-01

The deposition and transport of mercury (Hg) has been studied extensively in rural environments but is less understood in urbanized catchments, where elevated atmospheric Hg concentrations and impervious surfaces may efficiently deliver Hg to waterways in stormwater runoff. We determined the rate at which atmospheric Hg accumulates on windows, identified the importance of washoff in removing accumulated Hg, and measured atmospheric Hg concentrations to help understand the relationship between deposition and surface accumulation. The main study location was Toronto, Ontario. Similar samples were also collected from Austin, Texas for comparison of Hg accumulation between cities. Windows provided a good sampling surface because they are ubiquitous in urban environments and are easy to clean/blank allowing the assessment of contemporary Hg accumulation. Hg Accumulation rates were spatially variable ranging from 0.82 to 2.7 ng m-2 d-1 in Toronto and showed similar variability in Austin. The highest accumulation rate in Toronto was at the city center and was 5?? higher than the rural comparison site (0.58 ng m-2 d-1). The atmospheric total gaseous mercury (TGM) concentrations were less than 2?? higher between the rural and urban locations (1.7 ?? 0.3 and 2.7 ?? 1.1 ng m-3, respectively). The atmospheric particulate bound fraction (HgP), however, was more than 3?? higher between the rural and urban sites, which may have contributed to the higher urban Hg accumulation rates. Windows exposed to precipitation had 73 ?? 9% lower accumulation rates than windows sheltered from precipitation. Runoff collected from simulated rain events confirmed that most Hg accumulated on windows was easily removed and that most of the Hg in washoff was HgP. Our results indicate that the Hg flux from urban catchments will respond rapidly to changes in atmospheric concentrations due to the mobilization of the majority of the surface accumulated Hg during precipitation events. ?? 2008 Elsevier Ltd.

Uncertainty Analysis of Runoff Simulations and Parameter Identifiability in the Community Land Model – Evidence from MOPEX Basins

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Maoyi; Hou, Zhangshuan; Leung, Lai-Yung R.

2013-12-01

With the emergence of earth system models as important tools for understanding and predicting climate change and implications to mitigation and adaptation, it has become increasingly important to assess the fidelity of the land component within earth system models to capture realistic hydrological processes and their response to the changing climate and quantify the associated uncertainties. This study investigates the sensitivity of runoff simulations to major hydrologic parameters in version 4 of the Community Land Model (CLM4) by integrating CLM4 with a stochastic exploratory sensitivity analysis framework at 20 selected watersheds from the Model Parameter Estimation Experiment (MOPEX) spanning amore » wide range of climate and site conditions. We found that for runoff simulations, the most significant parameters are those related to the subsurface runoff parameterizations. Soil texture related parameters and surface runoff parameters are of secondary significance. Moreover, climate and soil conditions play important roles in the parameter sensitivity. In general, site conditions within water-limited hydrologic regimes and with finer soil texture result in stronger sensitivity of output variables, such as runoff and its surface and subsurface components, to the input parameters in CLM4. This study demonstrated the feasibility of parameter inversion for CLM4 using streamflow observations to improve runoff simulations. By ranking the significance of the input parameters, we showed that the parameter set dimensionality could be reduced for CLM4 parameter calibration under different hydrologic and climatic regimes so that the inverse problem is less ill posed.« less

Phosphorus loads from different urban storm runoff sources in southern China: a case study in Wenzhou City.

PubMed

Zhou, Dong; Bi, Chun-Juan; Chen, Zhen-Lou; Yu, Zhong-Jie; Wang, Jun; Han, Jing-Chao

2013-11-01

Storm runoff from six types of underlying surface area during five rainfall events in two urban study areas of Wenzhou City, China was investigated to measure phosphorus (P) concentrations and discharge rates. The average event mean concentrations (EMCs) of total phosphorus (TP), total dissolved phosphorus (TDP), and particulate phosphorus (PP) ranged from 0.02 to 2.5 mg · L(-1), 0.01 to 0.48 mg · L(-1), and 0.02 to 2.43 mg · L(-1), respectively. PP was generally the dominant component of TP in storm runoff, while the major form of P varied over time, especially in roof runoff, where TDP made up the largest portion in the latter stages of runoff events. Both TP and PP concentrations were positively correlated with pH, total suspended solids (TSS), and biochemical oxygen demand (BOD)/chemical oxygen demand (COD) concentrations (p<0.01), while TDP was positively correlated with BOD/COD only (p<0.01). In addition, the EMCs of TP and PP were negatively correlated with maximum rainfall intensity (p<0.05), while the EMCs of TDP positively correlated with the antecedent dry weather period (p<0.05). The annual TP emission fluxes from the two study areas were 367.33 and 237.85 kg, respectively. Underlying surface type determined the TP and PP loadings in storm runoff, but regional environmental conditions affected the export of TDP more significantly. Our results indicate that the removal of particles from storm runoff could be an effective measure to attenuate P loadings to receiving water bodies.

A protocol for conducting rainfall simulation to study soil runoff.

PubMed

Kibet, Leonard C; Saporito, Louis S; Allen, Arthur L; May, Eric B; Kleinman, Peter J A; Hashem, Fawzy M; Bryant, Ray B

2014-04-03

Rainfall is a driving force for the transport of environmental contaminants from agricultural soils to surficial water bodies via surface runoff. The objective of this study was to characterize the effects of antecedent soil moisture content on the fate and transport of surface applied commercial urea, a common form of nitrogen (N) fertilizer, following a rainfall event that occurs within 24 hr after fertilizer application. Although urea is assumed to be readily hydrolyzed to ammonium and therefore not often available for transport, recent studies suggest that urea can be transported from agricultural soils to coastal waters where it is implicated in harmful algal blooms. A rainfall simulator was used to apply a consistent rate of uniform rainfall across packed soil boxes that had been prewetted to different soil moisture contents. By controlling rainfall and soil physical characteristics, the effects of antecedent soil moisture on urea loss were isolated. Wetter soils exhibited shorter time from rainfall initiation to runoff initiation, greater total volume of runoff, higher urea concentrations in runoff, and greater mass loadings of urea in runoff. These results also demonstrate the importance of controlling for antecedent soil moisture content in studies designed to isolate other variables, such as soil physical or chemical characteristics, slope, soil cover, management, or rainfall characteristics. Because rainfall simulators are designed to deliver raindrops of similar size and velocity as natural rainfall, studies conducted under a standardized protocol can yield valuable data that, in turn, can be used to develop models for predicting the fate and transport of pollutants in runoff.

A Protocol for Conducting Rainfall Simulation to Study Soil Runoff

PubMed Central

Kibet, Leonard C.; Saporito, Louis S.; Allen, Arthur L.; May, Eric B.; Kleinman, Peter J. A.; Hashem, Fawzy M.; Bryant, Ray B.

2014-01-01

Rainfall is a driving force for the transport of environmental contaminants from agricultural soils to surficial water bodies via surface runoff. The objective of this study was to characterize the effects of antecedent soil moisture content on the fate and transport of surface applied commercial urea, a common form of nitrogen (N) fertilizer, following a rainfall event that occurs within 24 hr after fertilizer application. Although urea is assumed to be readily hydrolyzed to ammonium and therefore not often available for transport, recent studies suggest that urea can be transported from agricultural soils to coastal waters where it is implicated in harmful algal blooms. A rainfall simulator was used to apply a consistent rate of uniform rainfall across packed soil boxes that had been prewetted to different soil moisture contents. By controlling rainfall and soil physical characteristics, the effects of antecedent soil moisture on urea loss were isolated. Wetter soils exhibited shorter time from rainfall initiation to runoff initiation, greater total volume of runoff, higher urea concentrations in runoff, and greater mass loadings of urea in runoff. These results also demonstrate the importance of controlling for antecedent soil moisture content in studies designed to isolate other variables, such as soil physical or chemical characteristics, slope, soil cover, management, or rainfall characteristics. Because rainfall simulators are designed to deliver raindrops of similar size and velocity as natural rainfall, studies conducted under a standardized protocol can yield valuable data that, in turn, can be used to develop models for predicting the fate and transport of pollutants in runoff. PMID:24748061

Estimating phosphorus loss in runoff from manure and fertilizer for a phosphorus loss quantification tool.

PubMed

Vadas, P A; Good, L W; Moore, P A; Widman, N

2009-01-01

Nonpoint-source pollution of fresh waters by P is a concern because it contributes to accelerated eutrophication. Given the state of the science concerning agricultural P transport, a simple tool to quantify annual, field-scale P loss is a realistic goal. We developed new methods to predict annual dissolved P loss in runoff from surface-applied manures and fertilizers and validated the methods with data from 21 published field studies. We incorporated these manure and fertilizer P runoff loss methods into an annual, field-scale P loss quantification tool that estimates dissolved and particulate P loss in runoff from soil, manure, fertilizer, and eroded sediment. We validated the P loss tool using independent data from 28 studies that monitored P loss in runoff from a variety of agricultural land uses for at least 1 yr. Results demonstrated (i) that our new methods to estimate P loss from surface manure and fertilizer are an improvement over methods used in existing Indexes, and (ii) that it was possible to reliably quantify annual dissolved, sediment, and total P loss in runoff using relatively simple methods and readily available inputs. Thus, a P loss quantification tool that does not require greater degrees of complexity or input data than existing P Indexes could accurately predict P loss across a variety of management and fertilization practices, soil types, climates, and geographic locations. However, estimates of runoff and erosion are still needed that are accurate to a level appropriate for the intended use of the quantification tool.

Influence of Cattle Trails on Runoff Quantity and Quality.

PubMed

Miller, Jim J; Curtis, Tony; Chanasyk, David S; Willms, Walter D

2017-03-01

Cattle trails in grazed pastures close to rivers may adversely affect surface water quality of the adjacent river by directing runoff to it. The objective of this 3-yr study (2013-2015) in southern Alberta, Canada, was to determine if cattle trails significantly increased the risk of runoff and contaminants (sediment, nutrients) compared with the adjacent grazed pasture (control). A portable rainfall simulator was used to generate artificial rainfall (140 mm h) and runoff. The runoff properties measured were time to runoff and initial abstraction (infiltration), total runoff depth and average runoff rates, as well as concentrations and mass loads of sediment, N, and P fractions. Cattle trails significantly ( ≤ 0.10) decreased time to runoff and initial abstraction (26-32%) in the 2 yr measured and increased total runoff depth, runoff coefficients, and average runoff rates (21-51%) in 2 of 3 yr. Concentrations of sediment, N, and P fractions in runoff were not significantly greater for cattle trails than for control areas. However, mass loads of total suspended solids (57-85% increase), NH-N (31-90%), and dissolved reactive P (DRP) (30-92%) were significantly greater because of increased runoff volumes. Overall, runoff quantity and loads of sediment, NH-N, and DRP were greater for cattle trails compared with the adjacent grazed pasture, and hydrologic connection with cattle-access sites on the riverbank suggests that this could adversely affect water quality in the adjacent river. Extrapolation of the study results should be tempered by the specific conditions represented by this rainfall simulation study. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

The effect of leaf litter cover on surface runoff and soil erosion in Northern China.

PubMed

Li, Xiang; Niu, Jianzhi; Xie, Baoyuan

2014-01-01

The role of leaf litter in hydrological processes and soil erosion of forest ecosystems is poorly understood. A field experiment was conducted under simulated rainfall in runoff plots with a slope of 10%. Two common types of litter in North China (from Quercus variabilis, representing broadleaf litter, and Pinus tabulaeformis, representing needle leaf litter), four amounts of litter, and five rainfall intensities were tested. Results revealed that the litter reduced runoff and delayed the beginning of runoff, but significantly reduced soil loss (p<0.05). Average runoff yield was 29.5% and 31.3% less than bare-soil plot, and for Q. variabilis and P. tabulaeformis, respectively, and average sediment yield was 85.1% and 79.9% lower. Rainfall intensity significantly affected runoff (R = 0.99, p<0.05), and the efficiency in runoff reduction by litter decreased considerably. Runoff yield and the runoff coefficient increased dramatically by 72.9 and 5.4 times, respectively. The period of time before runoff appeared decreased approximately 96.7% when rainfall intensity increased from 5.7 to 75.6 mm h-1. Broadleaf and needle leaf litter showed similarly relevant effects on runoff and soil erosion control, since no significant differences (p≤0.05) were observed in runoff and sediment variables between two litter-covered plots. In contrast, litter mass was probably not a main factor in determining runoff and sediment because a significant correlation was found only with sediment in Q. variabilis litter plot. Finally, runoff yield was significantly correlated (p<0.05) with sediment yield. These results suggest that the protective role of leaf litter in runoff and erosion processes was crucial, and both rainfall intensity and litter characteristics had an impact on these processes.

The Effect of Leaf Litter Cover on Surface Runoff and Soil Erosion in Northern China

PubMed Central

Li, Xiang; Niu, Jianzhi; Xie, Baoyuan

2014-01-01

The role of leaf litter in hydrological processes and soil erosion of forest ecosystems is poorly understood. A field experiment was conducted under simulated rainfall in runoff plots with a slope of 10%. Two common types of litter in North China (from Quercus variabilis, representing broadleaf litter, and Pinus tabulaeformis, representing needle leaf litter), four amounts of litter, and five rainfall intensities were tested. Results revealed that the litter reduced runoff and delayed the beginning of runoff, but significantly reduced soil loss (p<0.05). Average runoff yield was 29.5% and 31.3% less than bare-soil plot, and for Q. variabilis and P. tabulaeformis, respectively, and average sediment yield was 85.1% and 79.9% lower. Rainfall intensity significantly affected runoff (R = 0.99, p<0.05), and the efficiency in runoff reduction by litter decreased considerably. Runoff yield and the runoff coefficient increased dramatically by 72.9 and 5.4 times, respectively. The period of time before runoff appeared decreased approximately 96.7% when rainfall intensity increased from 5.7 to 75.6 mm h−1. Broadleaf and needle leaf litter showed similarly relevant effects on runoff and soil erosion control, since no significant differences (p≤0.05) were observed in runoff and sediment variables between two litter-covered plots. In contrast, litter mass was probably not a main factor in determining runoff and sediment because a significant correlation was found only with sediment in Q. variabilis litter plot. Finally, runoff yield was significantly correlated (p<0.05) with sediment yield. These results suggest that the protective role of leaf litter in runoff and erosion processes was crucial, and both rainfall intensity and litter characteristics had an impact on these processes. PMID:25232858

MARKET INCENTIVES AND NONPOINT SOURCES: AN APPLICATION OF TRADABLE CREDITS TO URBAN STORMWATER MANAGEMENT

EPA Science Inventory

Excess stormwater runoff can cause serious pollution, habitat degradation and flooding in cities where growth in impervious surface area (such as pavement, buildings, etc.) has created a situation where stormwater runoff routinely exceeds the normal capacity of natural and constr...

Off site transport of fungicides with snowmelt and rainfall runoff from golf course fairway turf

USDA-ARS?s Scientific Manuscript database

Pesticides associated with the turfgrass industry have been detected in storm runoff and surface waters of urban watersheds; inferring contaminant contributions from residential, urban, and recreational sources. Golf course turf often requires multiple applications of pesticides at rates that exceed...

Snowmelt water drives higher soil erosion than rainfall water in a mid-high latitude upland watershed

NASA Astrophysics Data System (ADS)

Wu, Yuyang; Ouyang, Wei; Hao, Zengchao; Yang, Bowen; Wang, Li

2018-01-01

The impacts of precipitation and temperature on soil erosion are pronounced in mid-high latitude areas, which lead to seasonal variations in soil erosion. Determining the critical erosion periods and the reasons behind the increased erosion loads are essential for soil management decisions. Hence, integrated approaches combining experiments and modelling based on field investigations were applied to investigate watershed soil erosion characteristics and the dynamics of water movement through soils. Long-term and continuous data for surface runoff and soil erosion variation characteristics of uplands in a watershed were observed via five simulations by the Soil and Water Assessment Tool (SWAT). In addition, laboratory experiments were performed to quantify the actual soil infiltrabilities in snowmelt seasons (thawed treatment) and rainy seasons (non-frozen treatment). The results showed that over the course of a year, average surface runoff and soil erosion reached peak values of 31.38 mm and 1.46 t ha-1 a-1, respectively, in the month of April. They also ranked high in July and August, falling in the ranges of 23.73 mm to 24.91 mm and 0.55 t ha-1 a-1 to 0.59 t ha-1 a-1, respectively. With the infiltration time extended, thawed soils showed lower infiltrabilities than non-frozen soils, and the differences in soil infiltration amounts between these two were considerable. These results highlighted that soil erosion was very closely and positively correlated with surface runoff. Soil loss was higher in snowmelt periods than in rainy periods due to the higher surface runoff in early spring, and the decreased soil infiltrability in snowmelt periods contributed much to this higher surface runoff. These findings are helpful for identification of critical soil erosion periods when making soil management before critical months, especially those before snowmelt periods.

High Severity Wildfire Effect On Rainfall Infiltration And Runoff: A Cellular Automata Based Simulation

NASA Astrophysics Data System (ADS)

Vergara-Blanco, J. E.; Leboeuf-Pasquier, J.; Benavides-Solorio, J. D. D.

2017-12-01

A simulation software that reproduces rainfall infiltration and runoff for a storm event in a particular forest area is presented. A cellular automaton is utilized to represent space and time. On the time scale, the simulation is composed by a sequence of discrete time steps. On the space scale, the simulation is composed of forest surface cells. The software takes into consideration rain intensity and length, individual forest cell soil absorption capacity evolution, and surface angle of inclination. The software is developed with the C++ programming language. The simulation is executed on a 100 ha area within La Primavera Forest in Jalisco, Mexico. Real soil texture for unburned terrain and high severity wildfire affected terrain is employed to recreate the specific infiltration profile. Historical rainfall data of a 92 minute event is used. The Horton infiltration equation is utilized for infiltration capacity calculation. A Digital Elevation Model (DEM) is employed to reproduce the surface topography. The DEM is displayed with a 3D mesh graph where individual surface cells can be observed. The plot colouring renders water content development at the cell level throughout the storm event. The simulation shows that the cumulative infiltration and runoff which take place at the surface cell level depend on the specific storm intensity, fluctuation and length, overall terrain topography, cell slope, and soil texture. Rainfall cumulative infiltration for unburned and high severity wildfire terrain are compared: unburned terrain exhibits a significantly higher amount of rainfall infiltration.It is concluded that a cellular automaton can be utilized with a C++ program to reproduce rainfall infiltration and runoff under diverse soil texture, topographic and rainfall conditions in a forest setting. This simulation is geared for an optimization program to pinpoint the locations of a series of forest land remediation efforts to support reforestation or to minimize runoff.

Field application of farmstead runoff to vegetated filter strips: surface and subsurface water quality assessment.

PubMed

Larson, Rebecca A; Safferman, Steven I

2012-01-01

Farmstead runoff poses significant environmental impacts to ground and surface waters. Three vegetated filter strips were assessed for the treatment of dairy farmstead runoff at the soil surface and subsurface at 0.3- or 0. 46-m and 0. 76-m depths for numerous storm events. A medium-sized Michigan dairy was retrofitted with two filter strips on sandy loam soil and a third filter strip was implemented on a small Michigan dairy with sandy soil to collect and treat runoff from feed storage, manure storage, and other impervious farmstead areas. All filter strips were able to eliminate surface runoff via infiltration for all storm events over the duration of the study, eliminating pollutant contributions to surface water. Subsurface effluent was monitored to determine the contributing groundwater concentrations of numerous pollutants including chemical oxygen demand (COD), metals, and nitrates. Subsurface samples have an average reduction of COD concentrations of 20, 11, and 85% for the medium dairy Filter Strip 1 (FS1), medium dairy Filter Strip 2 (FS2), and the small Michigan dairy respectively, resulting in average subsurface concentrations of 355, 3960, and 718 mg L COD. Similar reductions were noted for ammonia and total Kjeldahl nitrogen (TKN) in the subsurface effluent. The small Michigan dairy was able to reduce the pollutant leachate concentrations of COD, TKN, and ammonia over a range of influent concentrations. Increased influent concentrations in the medium Michigan dairy filter strips resulted in an increase in COD, TKN, and ammonia concentrations in the leachate. Manganese was leached from the native soils at all filter strips as evidenced by the increase in manganese concentrations in the leachate. Nitrate concentrations were above standard drinking water limits (10 mg L), averaging subsurface concentrations of 11, 45, and 25 mg L NO-N for FS1, FS2, and the small Michigan dairy, respectively. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Predicting runoff of suspended solids and particulate phosphorus for selected Louisiana soils using simple soil tests.

PubMed

Udeigwe, Theophilus K; Wang, Jim J; Zhang, Hailin

2007-01-01

This study was conducted to evaluate the relationships among total suspended solids (TSS) and particulate phosphorus (PP) in runoff and selected soil properties. Nine Louisiana soils were subjected to simulated rainfall events, and runoff collected and analyzed for various parameters. A highly significant relationship existed between runoff TSS and runoff turbidity. Both runoff TSS and turbidity were also significantly related to runoff PP, which on average accounted for more than 98% of total P (TP) in the runoff. Runoff TSS was closely and positively related to soil clay content in an exponential fashion (y=0.10e0.01x, R2=0.91, P<0.001) while it was inversely related to soil electrical conductivity (EC) (y=0.02 x(-3.95), R2=0.70, P<0.01). A newly-devised laboratory test, termed "soil suspension turbidity" (SST) which measures turbidity in a 1:200 soil/water suspension, exhibited highly significant linear relationships with runoff TSS (y=0.06x-4.38, R2=0.82, P<0.001) and PP (y=0.04x+2.68, R2=0.85, P<0.001). In addition, SST alone yielded similar R2 value to that of combining soil clay content and EC in a multiple regression, suggesting that SST was able to account for the integrated effect of clay content and electrolytic background on runoff TSS. The SST test could be used for assessment and management of sediment and particulate nutrient losses in surface runoff.

The Effect of Atrazine on Louisiana Gulf Coast Estuarine Phytoplankton.

PubMed

Starr, Alexis V; Bargu, Sibel; Maiti, Kanchan; DeLaune, Ronald D

2017-02-01

Pesticides may enter water bodies in areas with a high proportion of agricultural land use through surface runoff, groundwater discharge, and erosion and thus negatively impact nontarget aquatic organisms. The herbicide atrazine is used extensively throughout the Midwest and enters the Mississippi River through surface runoff and groundwater discharge. The purpose of this study was to determine the extent of atrazine contamination in Louisiana's estuaries from Mississippi River water under different flow and nutrient regimes (spring and summer) and its effect on the biomass and oxygen production of the local phytoplankton community. The results showed that atrazine was consistently present in these systems at low levels. Microcosm experiments exposed to an atrazine-dilution series under low and high nutrient conditions to determine the phytoplankton stress response showed that high atrazine levels greatly decreased phytoplankton biomass and oxygen production. Phytoplankton exposed to low and moderate atrazine levels under high nutrient conditions were able to recover after an extended acclimation period. Communities grown under high nutrient conditions grew more rapidly and produced greater levels of oxygen than the low nutrient treatment groups, thus indicating that atrazine exposure may induce a greater stress response in phytoplankton communities under low-nutrient conditions. The native community also experienced a shift from more sensitive species, such as chlorophytes, to potentially more resilient species such as diatoms. The phytoplankton response to atrazine exposure at various concentrations can be especially important to greater trophic levels because their growth and abundance can determine the potential productivity of the entire ecosystem.

Annual subsurface transport of a red tide dinoflagellate to its bloom area: Water circulation patterns and organism distributions in the Chesapeake Bay

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tyler, M.A.; Seliger, H.H.

1978-03-01

An annual, long range, subsurface transport of Prorocentrum mariae-lebouriae, from the mouth of the Chesapeake Bay to its bloom area in the upper bay, a distance of 240 km, is described and completely documented. Prorocentrum in surface outflowing waters at the mouth of the bay is recruited in late winter into more dense inflowing coastal waters. Strong stratification produced by late winter--early spring surface runoff results in the development of a stable pycnocline. Prorocentrum, now in northward-flowing bottom waters, is retained in these bottom waters. It accumulates in a subsurface concentration maximum below the pycnocline and is transported northward tomore » reach its bloom area in the Patapsco River and north of the Bay Bridge by late spring. The rapidly decreasing depth of the upper bay causes the pycnocline to rise, mixing the previously light-limited Prorocentrum and its nutrient-rich bottom waters to the surface, where rapid growth ensues. Once the dinoflagellate is in surface waters, positive phototaxis, combined with both wind- and tide-driven surface convergences, produce dense surface patches or red tides. Prorocentrum is effectively retained in the bay until late winter by sequential inoculation into the tributary estuaries on the western shore, which exchange relatively slowly with bay waters. By late winter the annual cycle is complete. Prorocentrum is again in surface waters at the mouth of the bay where it is reintroduced into northward-flowing bottom waters. The mechanisms described provide a key to understanding the origins of subsurface chlorophyll maxima and the delivery of toxic dinoflagellates to coastal bloom areas.« less

RUNOFF, SEDIMENT TRANSPORT, AND SURFACE COLLAPSE AT A LOW-LEVEL RADIOACTIVE-WASTE BURIAL SITE NEAR SHEFFIELD, ILLINOIS.

USGS Publications Warehouse

Gray, John R.; Peters, Charles A.; ,

1985-01-01

Runoff, sediment transport, and precipitation were measured in three gaged basins composing two-thirds of the 20-acre site, and in a 3. 5-acre basin located 0. 3 mile south of the site. Locations and dimensions of surface collapses at the site were recorded by the site contractor. Volumes of collapsed material were calculated and converted to an equivalent weight of earth material by applying a mean value for the bulk density of soils at the site.

The integration of constructed wetlands into a treatment system for airport runoff.

PubMed

Revitt, D M; Worral, P; Brewer, D

2001-01-01

A new surface runoff treatment system has been designed for London Heathrow Airport, which incorporates separate floating constructed wetlands or reedbeds and sub-surface flow constructed wetlands as major pollutant removal systems. The primary requirement of the newly developed treatment system is to control the concentrations of glycols following their use as de-icers and anti-icers within the airport. The ability of reedbeds to contribute to this treatment role was fully tested through pilot scale, on-site experiments over a 2 year period. The average reductions in runoff BOD concentrations achieved by pilot scale surface flow and sub-surface flow reedbeds were 30.9% and 32.9%, respectively. The corresponding average glycol removal efficiencies were 54.2% and 78.3%, following shock dosing inputs. These treatment performances are used to predict the required full scale constructed wetland surface areas needed to attain the desired effluent water quality. The treatment system also incorporates aeration, storage and, combined with reedbed technology, has been designed to reduce a mixed inlet BOD concentration of 240 mg/l to less than 40 mg/l for water temperatures varying between 6 degrees C and 20 degrees C.

System analysis to estimate subsurface flow: from global level to the State of Minnesota

NASA Astrophysics Data System (ADS)

Shmagin, Boris A.; Kanivetsky, Roman

2002-06-01

Stream runoff data globally and in the state of Minnesota were used to estimate subsurface water flow. This system approach is based, in principal, on unity of groundwater and surface water systems, and it is in stark contrast to the traditional deterministic approach based on modeling. In coordination with methodology of system analysis, two levels of study were used to estimate subsurface flow. First, the global stream runoff data were assessed to estimate the temporal-spatial variability of surface water runoff. Factor analysis was used to study the temporal-spatial variability of global runoff for the period from 1918 to 1967. Results of these analysis demonstrate that the variability of global runoff could be represented by seven major components (factor scores) that could be grouped into seven distinct independent grouping from the total of 18 continental slopes on the Earth. Computed variance value in this analysis is 76% and supports such analysis. The global stream runoff for this period is stationary, and is more closely connected with the stream flow of Asia to the Pacific Ocean as well as with the stream runoff of North America towards the Arctic and Pacific Oceans. The second level examines the distribution of river runoff (annual and for February) for various landscapes and the hydrogeological conditions in the State of Minnesota (218,000 km2). The annual and minimal monthly rate of stream runoff for 115 gauging stations with a period of observation of 47 years (1935-1981) were used to characterize the spatio-temporal distribution of stream runoff in Minnesota. Results of this analysis demonstrate that the annual stream runoff rate changes from 6.3, towards 3.95, and then to 2.09 l s-1 km-2 (the difference is significant based on Student's criteria). These values in Minnesota correspond to ecological provinces from a mixed forest province towards the broadleaf forest and to prairie province, respectively. The distribution of minimal monthly stream runoff rate (February runoff) is controlled by hydrogeological systems in Minnesota. The difference between the two hydrogeological regions, Precambrian crystalline basement and Paleozoic artesian basin of 0.83 and 2.09 l/s/km2, is statistically significant. Within these regions, the monthly minimal runoff (0.5 and 1.68, and 0.87 and 3.11 l s-1 km-2 for February, respectively) is also distinctly different for delineated subregions, depending on whether or not the Quaternary cover is present. The spatio-temporal structure that emerges could thus be used to generate river runoff and subsurface flow maps at any scale - from the global level to local detail. Such analysis was carried out in Minnesota with the detailed mapping of the subsurface flow for the Twin Cities Metropolitan area.

System analysis to estimate subsurface flow: From global level to the State of Minnesota

USGS Publications Warehouse

Shmagin, B.A.; Kanivetsky, R.

2002-01-01

Stream runoff data globally and in the state of Minnesota were used to estimate subsurface water flow. This system approach is based, in principal, on unity of groundwater and surface water systems, and it is in stark contrast to the traditional deterministic approach based on modeling. In coordination with methodology of system analysis, two levels of study were used to estimate subsurface flow. First, the global stream runoff data were assessed to estimate the temporal-spatial variability of surface water runoff. Factor analysis was used to study the temporal-spatial variability of global runoff for the period from 1918 to 1967. Results of these analysis demonstrate that the variability of global runoff could be represented by seven major components (factor scores) that could be grouped into seven distinct independent grouping from the total of 18 continental slopes on the Earth. Computed variance value in this analysis is 76% and supports such analysis. The global stream runoff for this period is stationary, and is more closely connected with the stream flow of Asia to the Pacific Ocean as well as with the stream runoff of North America towards the Arctic and Pacific Oceans. The second level examines the distribution of river runoff (annual and for February) for various landscapes and the hydrogeological conditions in the State of Minnesota (218,000 km2). The annual and minimal monthly rate of stream runoff for 115 gauging stations with a period of observation of 47 years (1935-1981) were used to characterize the spatio-temporal distribution of stream runoff in Minnesota. Results of this analysis demonstrate that the annual stream runoff rate changes from 6.3, towards 3.95, and then to 2.09 1 s-1 km-2 (the difference is significant based on Student's criteria). These values in Minnesota correspond to ecological provinces from a mixed forest province towards the broadleaf forest and to prairie province, respectively. The distribution of minimal monthly stream runoff rate (February runoff) is controlled by hydrogeological systems in Minnesota. The difference between the two hydrogeological regions, Precambrian crystalline basement and Paleozoic artesian basin of 0.83 and 2.09 1/s/km2, is statistically significant. Within these regions, the monthly minimal runoff (0.5 and 1.68, and 0.87 and 3.11 1 s-1 km-2 for February, respectively) is also distinctly different for delineated subregions, depending on whether or not the Quaternary cover is present. The spatio-temporal structure that emerges could thus be used to generate river runoff and subsurface flow maps at any scale - from the global level to local detail. Such analysis was carried out in Minnesota with the detailed mapping of the subsurface flow for the Twin Cities Metropolitan area.

Quantification of turfgrass buffer performance in reducing transport of pesticides in surface runoff

USDA-ARS?s Scientific Manuscript database

Pesticides are used to control pests in managed biological system such as agricultural crops and golf course turf. Off-site transport of pesticides with runoff and their potential to adversely affect non-target aquatic organisms has inspired the evaluation of management practices to minimize pestic...

Evaluation of permeable friction course (PFC), roadside filter strips, dry swales, and wetland swales for treatment of highway stormwater runoff.

DOT National Transportation Integrated Search

2011-01-07

Stormwater runoff from roadways is a source of surface water pollution in North Carolina. The North Carolina Department of Transportation (NCDOT) is required to implement stormwater control measures (SCMs) in the linear environment. NCDOT has specifi...

How Much Is Enough? Minimal Responses of Water Quality and Stream Biota to Partial Retrofit Stormwater Management in a Suburban Neighborhood

EPA Science Inventory

Decentralized stormwater management approaches (e.g., biofiltration swales, pervious pavement, green roofs, rain gardens) that capture, detain, infiltrate, and filter runoff are now commonly used to minimize the impacts of stormwater runoff from impervious surfaces on aquatic eco...

Frequency of floods from a burned chaparral watershed

Treesearch

Iraj Nasseri

1989-01-01

Effects of brush fire on hydrologic characteristics of chaparral watersheds were analyzed. An unburned chaparral produces moderate surface runoff. The vegetation promotes infiltration by retarding the runoff and providing temporary storage during intense rainfall. The hydrologic characteristics of chaparral watershed, however, are drastically changed by fires. The high...

Development of a Special Provision on the Use of Pervious Concrete As a Stormwater Management Tool in Parking Lots

DOT National Transportation Integrated Search

2017-11-01

The abundance of impervious surfaces in developed areas leads to increased threats from stormwater runoff. The contaminants carried in unmanaged stormwater runoff in addition to higher volumes of water damage the natural environment and put undue str...

Evaluating the Accuracy of Common Runoff Estimation Methods for New Impervious Hot-Mix Asphalt

EPA Science Inventory

Accurately predicting runoff volume from impervious surfaces for water quality design events (e.g., 25.4 mm) is important for sizing green infrastructure stormwater control measures to meet water quality and infiltration design targets. The objective of this research was to quan...

Manure Application under Winter Conditions: Nutrient Runoff and Leaching Losses

USDA-ARS?s Scientific Manuscript database

Winter application of manure is commonly practiced and potential nutrient losses can be difficult to predict due to wide variations in weather within a year and between years. This study was conducted to determine nutrient losses via surface runoff and subsurface leachate from winter-applied manure ...

Manure application under winter conditions: Nutrient runoff and leaching losses

USDA-ARS?s Scientific Manuscript database

Winter application of manure is commonly practiced and potential nutrient losses are difficult to predict. This study was conducted in order to determine nutrient losses via surface runoff and subsurface leachate from winter-applied manure based on its relative placement with respect to snow. A labo...

Manure Application Under Winter Conditions: Nutrient Runoff and Leaching Losses

USDA-ARS?s Scientific Manuscript database

Winter application of manure is commonly practiced and potential nutrient losses are difficult to predict. This study was conducted in order to determine nutrient losses via surface runoff and subsurface leachate from winter-applied manure based on its relative placement with respect to snow. A labo...

A Laboratory Simulation of Urban Runoff and the Potential for Hydrograph Prediction with Curve Numbers

USDA-ARS?s Scientific Manuscript database

Urban drainages are mosaics of pervious and impervious surfaces, and prediction of runoff hydrology with a lumped modeling approach using the NRCS curve number may be appropriate. However, the prognostic capability of such a lumped approach is complicated by routing and connectivity amongst infiltra...

IMPEDIMENTS AND SOLUTIONS TO SUSTAINABLE, WATERSHED-SCALE URBAN STORMWATER MANAGEMENT: LESSONS FROM AUSTRALIA AND THE UNITED STATES

EPA Science Inventory

In urban and exurban areas, stormwater runoff is a primary stressor on surface waters (streams, wetlands, lakes, estuaries, and coastal waters). Conventional urban stormwater drainage systems often route runoff directly to streams and rivers, thus exacerbating pollutant inputs a...

Comparative analysis of water quality between runoff entrance and middle of recycling irrigation reservoirs

USDA-ARS?s Scientific Manuscript database

Recycling irrigation reservoirs (RIRs) are an emerging aquatic ecosystem of critical importance, for conserving and protecting increasingly scarce water resources. Here we compare water quality between runoff entrance and middle of four RIRs in nurseries in Virginia (VA) and Maryland (MD). Surface w...

Evaluation of Core Cultivation Practices to Reduce Ecological Risk of Pesticides in Runoff from Agrostis palustris

USDA-ARS?s Scientific Manuscript database

Pesticides associated with the turfgrass industry have been detected in storm runoff and surface waters of urban watersheds; invoking concern of their potential environmental effects and a desire to reduce their transport to non-target locations. Quantities of chlorpyrifos, dicamba, dimethylamine s...

Grenade Range Management Using Lime for Metals Immobilization and Explosives Transformation Treatability Study

DTIC Science & Technology

2007-06-01

of metals and explo- sives from HGR soil are transport in surface water and subsurface trans- port in leachate or pore water. Simple, innovative, and...and II.................................................................................... 41 RDX in leachate and runoff...44 Significant metals in leachate and runoff from Lysimeter Study I

Effect of urban stormwater runoff on ground water beneath recharge basins on Long Island, New York

USGS Publications Warehouse

Ku, H.F.; Simmons, D.L.

1986-01-01

Urban stormwater runoff was monitored during 1980-82 to investigate the source, type, quantity, and fate of contaminants routed to the more than 3,000 recharge basins on Long Island and to determine whether this runoff might be a significant source of contamination to the groundwater reservoir. Forty-six storms were monitored at five recharge basins in representative land use areas (strip commercial, shopping-mall parking lot, major highway, low-density residential, and medium-density residential). Runoff:precipitation ratios indicate that all storm runoff is derived from precipitation on impervious surfaces in the drainage area, except during storms of high intensity or long duration, when additional runoff can be derived from precipitation on permeable surfaces. Lead was present in highway runoff in concentrations up to 3300 micrograms/L, and chloride was found in parking lot runoff concentrations up to 1,100 mg/L during winter, when salt is used for deicing. In the five composite stormwater samples and nine groundwater grab samples that were analyzed for 113 EPA-designated ' priority pollutants, ' four constituents were detected in concentrations exceeding New York State guidelines of 50 micrograms/L for an individual organic compound in drinking water: p-chloro-m-cresol (79 micrograms/L); 2 ,4-dimethylphenol (96 micrograms/L); 4-nitrophenol (58 micrograms/L); and methylene chloride (230 micrograms/L in either groundwater or stormwater at the highway basin). One stormwater sample and two groundwater samples exceeded New York State guidelines for total organic compounds in drinking water (100 micrograms/L). The presence of these constituents is attributed to contamination from point sources rather than to the quality of runoff from urban areas. The median number of indicator bacteria in stormwater ranged from 0.1 to 10 billion MPN/100 ml. Fecal coliforms and fecal streptococci increased by 1 to 2 orders of magnitude during the warm season. The use of recharge basins to dispose of storm runoff does not appear to have significant adverse effects on groundwater quality in terms of the chemical and microbiological stormwater constituents studied. (Author 's abstract)

Phosphorus and nitrogen in runoff after phosphorus- or nitrogen-based manure applications.

PubMed

Miller, Jim J; Chanasyk, David S; Curtis, Tony W; Olson, Barry M

2011-01-01

Application of beef cattle () manure based on nitrogen (N) requirements of crops has resulted in elevated concentrations of soil test phosphorus (P) in surface soils, and runoff from this cropland can contribute to eutrophication of surface waters. We conducted a 3-yr field study (2005-2007) on a Lethbridge loam soil cropped to dryland barley () in southern Alberta, Canada to evaluate the effect of annual and triennial P-based and annual N-based feedlot manure on P and N in runoff. The manure was spring applied and incorporated. There was one unamended control plot. A portable rainfall simulator was used to generate runoff in the spring of each year after recent manure incorporation, and the runoff was analyzed for total P, total dissolved P, total particulate P, dissolved reactive P, total N, total dissolved N, total particulate N, NO-N, and NH-N. Annual or triennial P-based application resulted in significantly ( ≤ 0.05) lower (by 50 to 94%) concentrations or loads of mainly dissolved P fractions in runoff for some years compared with annual N-based application, and this was related to lower rates of annual manure P applied. For example, mean dissolved reactive P concentrations in 2006 and 2007 were significantly lower for the annual P-based (0.12-0.20 mg L) than for the annual N-based application (0.24-0.48 mg L), and mean values were significantly lower for the triennial P-based (0.06-0.13 mg L) than for the annual N-based application. In contrast, other P fractions in runoff were unaffected by annual P-based application. Our findings suggested no environmental benefit of annual P-based application over triennial P-based application with respect to P and N in runoff. Similar concentrations and loads of N fractions in runoff for the P- and N-based applications indicated that shifting to a P-based application would not significantly influence N in runoff. American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.

Further insight into the mechanism of heavy metals partitioning in stormwater runoff.

PubMed

Djukić, Aleksandar; Lekić, Branislava; Rajaković-Ognjanović, Vladana; Veljović, Djordje; Vulić, Tatjana; Djolić, Maja; Naunovic, Zorana; Despotović, Jovan; Prodanović, Dušan

2016-03-01

Various particles and materials, including pollutants, deposited on urban surfaces are washed off by stormwater runoff during rain events. The interactions between the solid and dissolved compounds in stormwater runoff are phenomena of importance for the selection and improvement of optimal stormwater management practices aimed at minimizing pollutant input to receiving waters. The objective of this research was to further investigate the mechanisms responsible for the partitioning of heavy metals (HM) between the solid and liquid phases in urban stormwater runoff. The research involved the collection of samples from urban asphalt surfaces, chemical characterization of the bulk liquid samples, solids separation, particle size distribution fractionation and chemical and physico-chemical characterization of the solid phase particles. The results revealed that a negligible fraction of HM was present in the liquid phase (less than 3% by weight), while there was a strong correlation between the total content of heavy metals and total suspended solids. Examinations of surface morphology and mineralogy revealed that the solid phase particles consist predominantly of natural macroporous materials: alpha quartz (80%), magnetite (11.4%) and silicon diphosphate (8.9%). These materials have a low surface area and do not have significant adsorptive capacity. These materials have a low surface area and do not have significant adsorptive capacity. The presence of HM on the surface of solid particles was not confirmed by scanning electron microscopy and energy dispersive X-ray microanalyses. These findings, along with the results of the liquid phase sample characterization, indicate that the partitioning of HM between the liquid and solid phases in the analyzed samples may be attributed to precipitation processes. Copyright © 2015 Elsevier Ltd. All rights reserved.