Temporal and spatial evolution characteristics of water environment quality in Heze
NASA Astrophysics Data System (ADS)
Gao, Qian; Zhao, Qiang; Li, Xiumei
2018-06-01
The evolution of water environment is relatively complicated. The study of its characteristics is helpful to grasp the general direction of spatial and temporal evolution of water environment in Heze city, and to carry out water resources development and water environment protection more rationally. The comprehensive pollution index method for calculation, and the observed data are handled by Excel. In order to facilitate the analysis of the basin, Arcgis is utilized to map the watershed map. In addition, for the spatial evolution, surfer12 is used to analyze the spatial evolution characteristics the spatial evolution, and to draw the pictures of spatial evolution of chemical oxygen demand and water quality evolution. The study shows that: (1) In Heze, the quality of water environment has been improved year by year from 2006 to 2013. In 2014, the water environment has deteriorated. The content of volatile phenol has increased greatly, and the evolution trend of COD is close to the trend of the comprehensive pollution index. (2) In terms of Spatial state of water environment, the water quality of Zhuzhao New River and Wanfu River is poor, and Dongyu River water quality is better. Zhuzhao New River and Wanfu River water qualityis often worse than grade V or V, and Dongyu River water quality is mostly maintained in the grade Ⅳ. Through the analysis on the spatial revolution characteristics of water quality and chemical oxygen demand(COD),as a result, water quality is poor in the northern region,and the water quality in the southern region is better in Heze. Although the water quality has changed in recent years, the overall pattern is relatively stable.
[Monitoring and analysis on evolution process of rainfall runoff water quality in urban area].
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%.
Huntington, T.G.; Hooper, R.P.; Peters, N.E.; Bullen, T.D.; Kendall, Carol
1993-01-01
The Panola Mountain Research Watershed (PMRW), located in the Panola Mountain State Conservation Park near Stockbridge, Georgia has been selected as a core research watershed under the Water, Energy and Biogeochemical Budgets (WEBB) research initiative of the U.S. Geological Survey (USGS) Global Climate Change Program. This research plan describes ongoing and planned research activities at PMRW from 1984 to 1994. Since 1984, PMRW has been studied as a geochemical process research site under the U.S. Acid Precipitation Thrust Program. Research conducted under this Thrust Program focused on the estimation of dry atmospheric deposition, short-term temporal variability of streamwater chemistry, sulfate adsorption characteristics of the soils, groundwater chemistry, throughfall chemistry, and streamwater quality. The Acid Precipitation Thrust Program continues (1993) to support data collection and a water-quality laboratory. Proposed research to be supported by the WEBB program is organized in 3 interrelated categories: streamflow generation and water-quality evolution, weathering and geochemical evolution, and regulation of soil-water chemistry. Proposed research on streamflow generation and water-quality evolution will focus on subsurface water movement, its influence in streamflow generation, and the associated chemical changes of the water that take place along its flowpath. Proposed research on weathering and geochemical evolution will identify the sources of cations observed in the streamwater at Panola Mountain and quantify the changes in cation source during storms. Proposed research on regulation of soil-water chemistry will focus on the poorly understood processes that regulate soil-water and groundwater chemistry. (USGS)
Ma, Jinzhu; Ding, Zhenyu; Wei, Guoxiao; Zhao, Hua; Huang, Tianming
2009-02-01
Based on surveys and chemical analyses, we performed a case study of the surface water and groundwater quality in the Wuwei basin, in order to understand the sources of water pollution and the evolution of water quality in Shiyang river. Concentrations of major chemical elements in the surface water were related to the distance downstream from the source of the river, with surface water in the upstream reaches of good quality, but the river from Wuwei city to the Hongya reservoir was seriously polluted, with a synthetic pollution index of 25. Groundwater quality was generally good in the piedmont with dominant bicarbonate and calcium ions, but salinity was high and nitrate pollution occurs in the northern part of the basin. Mineralization of the groundwater has changed rapidly during the past 20 years. There are 23 wastewater outlets that discharge a total of 22.4 x 10(6)m(3)y(-1) into the river from Wuwei city, which, combined with a reduction of inflow water, were found to be the major causes of water pollution. Development of fisheries in the Hongya reservoir since 2000 has also contributed to the pollution. The consumption of water must be decreased until it reaches the sustainable level permitted by the available resources in the whole basin, and discharge of wastes must also be drastically reduced.
THE EVOLUTION OF WATER QUALITY IN THE UNITED STATES - 1922-2003
The microbiological quality of recreational waters was first discussed in the United States as early as 1922 by the American Public Health Association's Committee on Bathing Beaches (APHA,1922) . The Committee surveyed 2000 physicians and state health officials inquiring about th...
NASA Astrophysics Data System (ADS)
Neville, J.; Vose, J. M.; Nichols, E. G.; Jass, T. L.; Emanuel, R. E.; McRae, J.
2016-12-01
Water quality and land use/land cover (LULC) are linked intimately in many watersheds, although exact relationships are often nonlinear and sometimes complex. Together with watershed topography, LULC can affect water quality in various ways. As such, attributing water quality characteristics to LULC variations (either in space or time) can be difficult. Many studies seek to understand these relationships from a Eulerian reference frame, which typically involves many samples or observations through time at a fixed location. Here we explore an alternative approach to understanding relationships between LULC and water quality that relies on a Lagrangian, or moving, reference frame, in which the effects of LULC and watershed topography on water quality can be observed through a different lens. We studied three reaches of the Lumber River, a blackwater stream in North Carolina's Coastal Plain, to assess relationships between LULC and water quality in a watershed that is a patchwork of agriculture, forests, wetlands and developed land. Our study combines spatially intensive water quality measurements (temperature, specific conductance, dissolved oxygen, pH and nitrate concentration), collected by boat, with geospatial analyses of LULC to understand influences on the spatial evolution of reach-scale water quality. In particular, we investigate relationships between spatial patterns in nitrate and the changing spatial characteristics of the watershed integrated at sampling points along each reach. We also assess relationships between nitrate and other water quality variables, such as pH, temperature, and dissolved oxygen to better understand the potential role of in-stream nutrient processing in observed spatial patterns. This work has implications for the regulation and management of agriculture, wetlands, and forests in a region that has long struggled to balance agriculture, a major economic driver, with water quality, a major concern for recreation and cultural practices locally and for nutrient sensitive coastal environments downstream.
Evolution of regulatory targets for drinking water quality.
Sinclair, Martha; O'Toole, Joanne; Gibney, Katherine; Leder, Karin
2015-06-01
The last century has been marked by major advances in the understanding of microbial disease risks from water supplies and significant changes in expectations of drinking water safety. The focus of drinking water quality regulation has moved progressively from simple prevention of detectable waterborne outbreaks towards adoption of health-based targets that aim to reduce infection and disease to a level well below detection limits at the community level. This review outlines the changes in understanding of community disease and waterborne risks that prompted development of these targets, and also describes their underlying assumptions and current context. Issues regarding the appropriateness of selected target values, and how continuing changes in knowledge and practice may influence their evolution, are also discussed.
Stoler, Justin; Tutu, Raymond A; Ahmed, Hawa; Frimpong, Lady Asantewa; Bello, Mohammed
2014-02-01
Sachet water has become an important primary source of drinking water in western Africa, but little is known about bacteriologic quality and improvements to quality control given the recent, rapid evolution of this industry. This report examines basic bacteriologic indicators for 60 sachet water samples from two very low-income communities in Accra, Ghana, and explores the relationship between local perceptions of brand quality and bacteriologic quality after controlling for characteristics of the vending environment. No fecal contamination was detected in any sample, and 82% of total heterotrophic bacteria counts were below the recommended limit for packaged water. Sachets from brands with a positive reputation for quality were 90% less likely to present any level of total heterotrophic bacteria after controlling for confounding factors. These results contrast with much of the recent sachet water quality literature and may indicate substantial progress in sachet water regulation and quality control.
Stoler, Justin; Tutu, Raymond A.; Ahmed, Hawa; Frimpong, Lady Asantewa; Bello, Mohammed
2014-01-01
Sachet water has become an important primary source of drinking water in western Africa, but little is known about bacteriologic quality and improvements to quality control given the recent, rapid evolution of this industry. This report examines basic bacteriologic indicators for 60 sachet water samples from two very low-income communities in Accra, Ghana, and explores the relationship between local perceptions of brand quality and bacteriologic quality after controlling for characteristics of the vending environment. No fecal contamination was detected in any sample, and 82% of total heterotrophic bacteria counts were below the recommended limit for packaged water. Sachets from brands with a positive reputation for quality were 90% less likely to present any level of total heterotrophic bacteria after controlling for confounding factors. These results contrast with much of the recent sachet water quality literature and may indicate substantial progress in sachet water regulation and quality control. PMID:24379244
Geochemical Signature of Natural Water Recharge in the Jungar Basin and Its Response to Climate.
Zhu, Bingqi; Yu, Jingjie; Rioual, Patrick
2016-01-01
This paper analyzed the physico-chemical characteristics of natural waters in a drainage system of the Jungar Basin, northwestern China to identify chemical evolution and recharge mechanisms of natural waters in an arid environment. The waters studied are different in mineralization, but are typically carbonate rivers and alkaline in nature. No Cl-dominated water type occurs, indicating an early stage of water evolution. Regolith and geomorphological parameters controlling ground-surface temperature may play a large role in the geological evolution of the water. Three main morphological and hydrological units are reflected in water physico-chemistry. Climate influences the salinization of natural waters substantially. Direct recharge from seasonal snow and ice-melt water and infiltration of rain to the ground are significant recharge processes for natural waters, but recharge from potential deep groundwater may be less important. The enrichment of ions in lakes has been mainly caused by evaporation rather than through the quality change of the recharged water.
NASA Astrophysics Data System (ADS)
Cunha, Davi Gasparini Fernandes; Benassi, Simone Frederigi; de Falco, Patrícia Bortoletto; do Carmo Calijuri, Maria
2016-03-01
Artificial reservoirs have been used for drinking water supply, other human activities, flood control and pollution abatement worldwide, providing overall benefits to downstream water quality. Most reservoirs in Brazil were built during the 1970s, but their long-term patterns of trophic status, water chemistry, and nutrient removal are still not very well characterized. We aimed to evaluate water quality time series (1985-2010) data from the riverine and lacustrine zones of the transboundary Itaipu Reservoir (Brazil/Paraguay). We examined total phosphorus and nitrogen, chlorophyll a concentrations, water transparency, and phytoplankton density to look for spatial and temporal trends and correlations with trophic state evolution and nutrient retention. There was significant temporal and spatial water quality variation ( P < 0.01, ANCOVA). The results indicated that the water quality and structure of the reservoir were mainly affected by one internal force (hydrodynamics) and one external force (upstream cascading reservoirs). Nutrient and chlorophyll a concentrations tended to be lower in the lacustrine zone and decreased over the 25-year timeframe. Reservoir operational features seemed to be limiting primary production and phytoplankton development, which exhibited a maximum density of 6050 org/mL. The relatively small nutrient concentrations in the riverine zone were probably related to the effect of the cascade reservoirs upstream of Itaipu and led to relatively low removal percentages. Our study suggested that water quality problems may be more pronounced immediately after the filling phase of the artificial reservoirs, associated with the initial decomposition of drowned vegetation at the very beginning of reservoir operation.
Cunha, Davi Gasparini Fernandes; Benassi, Simone Frederigi; de Falco, Patrícia Bortoletto; Calijuri, Maria do Carmo
2016-03-01
Artificial reservoirs have been used for drinking water supply, other human activities, flood control and pollution abatement worldwide, providing overall benefits to downstream water quality. Most reservoirs in Brazil were built during the 1970s, but their long-term patterns of trophic status, water chemistry, and nutrient removal are still not very well characterized. We aimed to evaluate water quality time series (1985-2010) data from the riverine and lacustrine zones of the transboundary Itaipu Reservoir (Brazil/Paraguay). We examined total phosphorus and nitrogen, chlorophyll a concentrations, water transparency, and phytoplankton density to look for spatial and temporal trends and correlations with trophic state evolution and nutrient retention. There was significant temporal and spatial water quality variation (P < 0.01, ANCOVA). The results indicated that the water quality and structure of the reservoir were mainly affected by one internal force (hydrodynamics) and one external force (upstream cascading reservoirs). Nutrient and chlorophyll a concentrations tended to be lower in the lacustrine zone and decreased over the 25-year timeframe. Reservoir operational features seemed to be limiting primary production and phytoplankton development, which exhibited a maximum density of 6050 org/mL. The relatively small nutrient concentrations in the riverine zone were probably related to the effect of the cascade reservoirs upstream of Itaipu and led to relatively low removal percentages. Our study suggested that water quality problems may be more pronounced immediately after the filling phase of the artificial reservoirs, associated with the initial decomposition of drowned vegetation at the very beginning of reservoir operation.
New rapid methods will be discussed, including their advantages and disadvantages. This presentation will also provide a historical perspective on the evolution of water quality standards and the rationale for risk-based regulations for recreational waters.
NASA Astrophysics Data System (ADS)
Arnoux, Marie; Barbecot, Florent; Gibert-Brunet, Elisabeth; Gibson, John; Noret, Aurélie
2017-11-01
Lakes are under increasing pressure due to widespread anthropogenic impacts related to rapid development and population growth. Accordingly, many lakes are currently undergoing a systematic decline in water quality. Recent studies have highlighted that global warming and the subsequent changes in water use may further exacerbate eutrophication in lakes. Lake evolution depends strongly on hydrologic balance, and therefore on groundwater connectivity. Groundwater also influences the sensitivity of lacustrine ecosystems to climate and environmental changes, and governs their resilience. Improved characterization of groundwater exchange with lakes is needed today for lake preservation, lake restoration, and sustainable management of lake water quality into the future. In this context, the aim of the present paper is to determine if the future evolution of the climate, the population, and the recharge could modify the geochemistry of lakes (mainly isotopic signature and quality via phosphorous load) and if the isotopic monitoring of lakes could be an efficient tool to highlight the variability of the water budget and quality. Small groundwater-connected lakes were chosen to simulate changes in water balance and water quality expected under future climate change scenarios, namely representative concentration pathways (RCPs) 4.5 and 8.5. Contemporary baseline conditions, including isotope mass balance and geochemical characteristics, were determined through an intensive field-based research program prior to the simulations. Results highlight that future lake geochemistry and isotopic composition trends will depend on four main parameters: location (and therefore climate conditions), lake catchment size (which impacts the intensity of the flux change), lake volume (which impacts the range of variation), and lake G index (i.e., the percentage of groundwater that makes up total lake inflows), the latter being the dominant control on water balance conditions, as revealed by the sensitivity of lake isotopic composition. Based on these model simulations, stable isotopes appear to be especially useful for detecting changes in recharge to lakes with a G index of between 50 and 80 %, but response is non-linear. Simulated monthly trends reveal that evolution of annual lake isotopic composition can be dampened by opposing monthly recharge fluctuations. It is also shown that changes in water quality in groundwater-connected lakes depend significantly on lake location and on the intensity of recharge change.
Musgrove, MaryLynn; Fahlquist, Lynne; Houston, Natalie A.; Lindgren, Richard J.; Ging, Patricia B.
2010-01-01
As part of the National Water-Quality Assessment Program, the U.S. Geological Survey collected and analyzed groundwater samples during 1996-2006 from the San Antonio segment of the Edwards aquifer of central Texas, a productive karst aquifer developed in Cretaceous-age carbonate rocks. These National Water-Quality Assessment Program studies provide an extensive dataset of groundwater geochemistry and water quality, consisting of 249 groundwater samples collected from 136 sites (wells and springs), including (1) wells completed in the shallow, unconfined, and urbanized part of the aquifer in the vicinity of San Antonio (shallow/urban unconfined category), (2) wells completed in the unconfined (outcrop area) part of the regional aquifer (unconfined category), and (3) wells completed in and springs discharging from the confined part of the regional aquifer (confined category). This report evaluates these data to assess geochemical evolution processes, including local- and regional-scale processes controlling groundwater geochemistry, and to make water-quality observations pertaining to sources and distribution of natural constituents and anthropogenic contaminants, the relation between geochemistry and hydrologic conditions, and groundwater age tracers and travel time. Implications for monitoring water-quality trends in karst are also discussed. Geochemical and isotopic data are useful tracers of recharge, groundwater flow, fluid mixing, and water-rock interaction processes that affect water quality. Sources of dissolved constituents to Edwards aquifer groundwater include dissolution of and geochemical interaction with overlying soils and calcite and dolomite minerals that compose the aquifer. Geochemical tracers such as magnesium to calcium and strontium to calcium ratios and strontium isotope compositions are used to evaluate and constrain progressive fluid-evolution processes. Molar ratios of magnesium to calcium and strontium to calcium in groundwater typically increase along flow paths; results for samples of Edwards aquifer groundwater show an increase from shallow/urban unconfined, to unconfined, to confined groundwater categories. These differences are consistent with longer residence times and greater extents of water-rock interaction controlling fluid compositions as groundwater evolves from shallow unconfined groundwater to deeper confined groundwater. Results for stable isotopes of hydrogen and oxygen indicate specific geochemical processes affect some groundwater samples, including mixing with downdip saline water, mixing with recent recharge associated with tropical cyclonic storms, or mixing with recharge water than has undergone evaporation. The composition of surface water recharging the aquifer, as well as mixing with downdip water from the Trinity aquifer or the saline zone, also might affect water quality. A time-series record (1938-2006) of discharge at Comal Springs, one of the major aquifer discharge points, indicates an upward trend for nitrate and chloride concentrations, which likely reflects anthropogenic activities. A small number of organic contaminants were routinely or frequently detected in Edwards aquifer groundwater samples. These were the pesticides atrazine, its degradate deethylatrazine, and simazine; the drinking-water disinfection byproduct chloroform; and the solvent tetrachloroethene. Detection of these contaminants was most frequent in samples of the shallow/urban unconfined groundwater category and least frequent in samples of the unconfined groundwater category. Results indicate that the shallow/urban unconfined part of the aquifer is most affected by anthropogenic contaminants and the unconfined part of the aquifer is the least affected. The high frequency of detection for these anthropogenic contaminants aquifer-wide and in samples of deep, confined groundwater indicates that the entire aquifer is susceptible to water-quality changes as a result of anthropogenic activities. L
NASA Astrophysics Data System (ADS)
Matiatos, Ioannis; Paraskevopoulou, Vasiliki; Lazogiannis, Konstantinos; Botsou, Fotini; Dassenakis, Manos; Ghionis, George; Alexopoulos, John D.; Poulos, Serafim E.
2018-06-01
River deltas sustain important ecosystems with rich biodiversity and large biomass, as well as human populations via the availability of water and food sources. Anthropogenic activities, such as urbanization, tourism and agriculture, may pose threats to river deltas. The knowledge of the factors controlling the regional water quality regime in these areas is important for planning sustainable use and management of the water resources. Here, hydrochemical methods and multivariate statistical techniques were combined to investigate the shallow aquifer of the Pinios River (Thessaly) deltaic plain with respect to water quality, hydrogeochemical evolution and interactions between groundwater and surface water bodies. Water quality assessment indicated that most of the river and groundwater samples fully comply with the criteria set by the Drinking Water Directive (98/83/EC). The river is recharged mainly from springs of the Tempi valley and the shallow aquifer, and to a lesser degree from precipitation, throughout the year. The hydrogeochemical characteristics indicated a cation (Ca, Mg, and Na) bicarbonate water type, which evolves to calcium-chloride, sodium-bicarbonate and sodium-chloride water type, in the northern part of the delta. Calcite and dolomite dissolution determined the major ion chemistry, but other processes, such as silicate weathering and cation exchange reactions, also contributed. In the northern part of the plain, the interaction with the deeper aquifer enriched the shallow aquifer with Na and Cl ions. Principal Component Analysis showed that five components (PCs) explain 77% of the total variance of water quality parameters; these are: (1) salinity; (2) water-silicate rocks interaction; (3) hardness due to calcite dissolution, and cation exchange processes; (4) nitrogen pollution; and (5) non-N-related artificial fertilizers. This study demonstrated that the variation of water hydrochemistry in the deltaic plain could be attributed to natural and anthropogenic processes. The interpretation of the PCA results dictated the parameters used for the development of a modified Water Quality Index (WQI), to provide a more comprehensive spatial representation of the water quality of the river delta.
Andrews, William J.; Stark, James R.; Fong, Alison L.; Fallon, James D.
2005-01-01
Although land use had substantial effects on ground-water quality, the distribution of contaminants in the aquifer also is affected by complex combinations of factors and processes that include sources of natural and anthropogenic contaminants, three-dimensional advective flow, physical and hydrologic settings, age and evolution of ground water, and transformation of chemical compounds along the flow system. Compounds such as nitrate and dissolved oxygen were greatest in water samples from the upgradient end of the flow system and near the water table. Specific conductance and dissolved solids increased along the flow system and with depth due to increase in residence time in the flow system and dissolution of aquifer materials.
THE EVOLUTION OF SYNTHETICALLY PRECIPITATED COPPER SOLIDS
The objective of this study was to explore the effect of water quality, particularly chloride and sulfate, on copper mineral formation. Copper-sulfate and chloride compounds are often found on the surface of copper pipes in drinking water distribution systems. When attempting to ...
Managing water quality under drought conditions in the Llobregat River Basin.
Momblanch, Andrea; Paredes-Arquiola, Javier; Munné, Antoni; Manzano, Andreu; Arnau, Javier; Andreu, Joaquín
2015-01-15
The primary effects of droughts on river basins include both depleted quantity and quality of the available water resources, which can render water resources useless for human needs and simultaneously damage the environment. Isolated water quality analyses limit the action measures that can be proposed. Thus, an integrated evaluation of water management and quality is warranted. In this study, a methodology consisting of two coordinated models is used to combine aspects of water resource allocation and water quality assessment. Water management addresses water allocation issues by considering the storage, transport and consumption elements. Moreover, the water quality model generates time series of concentrations for several pollutants according to the water quality of the runoff and the demand discharges. These two modules are part of the AQUATOOL decision support system shell for water resource management. This tool facilitates the analysis of the effects of water management and quality alternatives and scenarios on the relevant variables in a river basin. This paper illustrates the development of an integrated model for the Llobregat River Basin. The analysis examines the drought from 2004 to 2008, which is an example of a period when the water system was quantitative and qualitatively stressed. The performed simulations encompass a wide variety of water management and water quality measures; the results provide data for making informed decisions. Moreover, the results demonstrated the importance of combining these measures depending on the evolution of a drought event and the state of the water resources system. Copyright © 2014 Elsevier B.V. All rights reserved.
The Rise and Fall of Industrial Agriculture
ERIC Educational Resources Information Center
Geno, Larry M.
1976-01-01
This article analyzes the evolution of industrial agriculture in Canada. Population pressures and technology caused the development of industrial agriculture. Although total crop yields have increased, energy efficiency and nutritional quality have decreased. Also intensive agriculture has degraded the soil and lowered air and water qualities. (MR)
NASA Astrophysics Data System (ADS)
Boubakri, S.; Rhinane, H.
2017-11-01
The monitoring of water quality is, in most cases, managed in the laboratory and not on real time bases. Besides this process being lengthy, it doesn't provide the required specifications to describe the evolution of the quality parameters that are of interest. This study presents the integration of Geographic Information Systems (GIS) with wireless sensor networks (WSN) aiming to create a system able to detect the parameters like temperature, salinity and conductivity in a Moroccan catchment scale and transmit information to the support station. This Information is displayed and evaluated in a GIS using maps and spatial dashboard to monitor the water quality in real time.
Development of a Methodology for the Derivation of Aquatic Plant Water Quality Criteria
Aquatic plants form the base of most aquatic food chains, comprise biodiversity-building habitats and are functionally important in carbon assimilation and oxygen evolution. The USEPA, as stated in the Clean Water Act, establishes criterion values for various pollutants found in ...
Groundwater hydrogeochemical characteristics in rehabilitated coalmine spoils
NASA Astrophysics Data System (ADS)
Gomo, M.; Masemola, E.
2016-04-01
The investigation aims to identify and describe hydrogeochemical processes controlling the evolution of groundwater chemistry in rehabilitated coalmine spoils and their overall influence on groundwater quality at a study area located in the Karoo basin of South Africa. A good understanding of the processes that controls the evolution of the mine water quality is vital for the planning, application and management of post-mining remedial actions. The study utilises scatter plots, statistical analysis, PHREEQC hydrogeochemical modelling, stoichiometric reaction ratios analysis, and the expanded Durov diagram as complimentary tools to interpret the groundwater chemistry data collected from monitoring boreholes from 1995 to 2014. Measured pH ranging between 6-8 and arithmetic mean of 7.32 shows that the groundwater system is characterised by circumneutral hydrogeochemical conditions period. Comparison of measured groundwater ion concentrations to theoretical reaction stoichiometry identifies Dolomite-Acid Mine Drainage (AMD) neutralisation as the main hydrogeochemical process controlling the evolution of the groundwater chemistry. Hydrogeochemical modelling shows that, the groundwater has temporal variations of calcite and dolomite saturation indices characterised by alternating cycles of over-saturation and under-saturation that is driven by the release of sulphate, calcium and magnesium ions from the carbonate-AMD neutralization process. Arithmetic mean concentrations of sulphate, calcium and magnesium are in the order of 762 mg/L, 141 mg/L and 108 mg/L. Calcium and magnesium ions contribute to very hard groundwater quality conditions. Classification based on total dissolved solids (TDS), shows the circumneutral water is of poor to unacceptable quality for drinking purposes. Despite its ability to prevent AMD formation and leaching of metals, the dolomite-AMD neutralisation process can still lead to problems of elevated TDS and hardness which mines should be aware of when developing water quality management plans.
Development and testing of a fast conceptual river water quality model.
Keupers, Ingrid; Willems, Patrick
2017-04-15
Modern, model based river quality management strongly relies on river water quality models to simulate the temporal and spatial evolution of pollutant concentrations in the water body. Such models are typically constructed by extending detailed hydrodynamic models with a component describing the advection-diffusion and water quality transformation processes in a detailed, physically based way. This approach is too computational time demanding, especially when simulating long time periods that are needed for statistical analysis of the results or when model sensitivity analysis, calibration and validation require a large number of model runs. To overcome this problem, a structure identification method to set up a conceptual river water quality model has been developed. Instead of calculating the water quality concentrations at each water level and discharge node, the river branch is divided into conceptual reservoirs based on user information such as location of interest and boundary inputs. These reservoirs are modelled as Plug Flow Reactor (PFR) and Continuously Stirred Tank Reactor (CSTR) to describe advection and diffusion processes. The same water quality transformation processes as in the detailed models are considered but with adjusted residence times based on the hydrodynamic simulation results and calibrated to the detailed water quality simulation results. The developed approach allows for a much faster calculation time (factor 10 5 ) without significant loss of accuracy, making it feasible to perform time demanding scenario runs. Copyright © 2017 Elsevier Ltd. All rights reserved.
Maqsoud, Abdelkabir; Neculita, Carmen Mihaela; Bussière, Bruno; Benzaazoua, Mostafa; Dionne, Jean
2016-05-01
The abandoned Manitou mine site has produced acid mine drainage (AMD) for several decades. In order to limit the detrimental environmental impacts of AMD, different rehabilitation scenarios were proposed and analyzed. The selected rehabilitation scenario was to use fresh tailings from the neighboring Goldex gold mine as monolayer cover and to maintain an elevated water table. In order to assess the impact of the Goldex tailing deposition on the hydrogeochemistry of the Manitou mine site, a network of 30 piezometers was installed. These piezometers were used for continuous measurement of the groundwater level, as well as for water sampling campaigns for chemical quality monitoring, over a 3-year period. Hydrochemical data were analyzed using principal component analysis. Results clearly showed the benefic impact of fresh tailing deposition on the groundwater quality around the contaminated area. These findings were also confirmed by the evolution of electrical conductivity. In addition to the improvement of the physicochemical quality of water on the Manitou mine site, new tailing deposition induced an increase of water table level. However, at this time, the Manitou reactive tailings are not completely submerged and possible oxidation might still occur, especially after ceasing of the fresh tailing deposition. Therefore, complementary rehabilitation scenarios should still be considered.
NASA Astrophysics Data System (ADS)
Wan, Liyang; Cai, Wenjia; Jiang, Yongkai; Wang, Can
2016-07-01
Globalization enables the transfer of impacts on water availability. We argue that the threat should be evaluated not only by decrease of quantity, but more importantly by the degradation of water quality in exporting countries. Grouping the world into fourteen regions, this paper establishes a multi-region input-output framework to calculate the nitrogen-related grey water footprint and a water quality-induced scarcity index caused by pollution, for the period of 1995 to 2009. It is discovered that grey water embodied in international trade has been growing faster than total grey water footprint. China, the USA and India were the three top grey water exporters which accounted for more than half the total traded grey water. Dilemma rose when China and India were facing highest grey water scarcity. The EU and the USA were biggest grey water importers that alleviated their water stress by outsourcing water pollution. A structural decomposition analysis is conducted to study the drivers to the evolution of virtual flows of grey water under globalization during the period of 1995 to 2009. The results show that despite the technical progress that offset the growth of traded grey water, structural effects under globalization including both evolution in the globalized economic system and consumption structure, together with consumption volume made a positive contribution. It is found that the structural effect intensified the pollution-induced water scarcity of exporters as it generally increased all nations’ imported grey water while resulting in increases in only a few nations’ exported grey water, such as Brazil, China and Indonesia. At last, drawing from the ‘cap-and-trade’ and ‘boarder-tax-adjustment’ schemes, we propose policy recommendations that ensure water security and achieve environmentally sustainable trade from both the sides of production and consumption.
NASA Astrophysics Data System (ADS)
Lachaal, Fethi; Chekirbane, Anis; Chargui, Sameh; Sellami, Haykel; Tsujimura, Maki; Hezzi, Hmida; Faycel, Jelassi; Mlayah, Ammar
2016-12-01
Information on groundwater quantity as well as quality is required by water managers and decision-makers for defining a sustainable management strategy. This requires a comprehensive assessment of the surface water and groundwater resources. This paper provides an assessment of water resources management strategy in the Grombalia region (Northeast Tunisia) and its impact on quantity and quality evolution of groundwater resources based on an approach that combines (i) hydro-climatic data, (ii) field monitoring, (iii) historic piezometric records, and (iv) geochemical and stable isotopes (δ18O and δ2H) analyses. We apply this approach to identify the origin of the various water resources and outline how the actual water management impact the quantity and quality of the groundwater in the region. As consequence of poor water resources management, the shallow groundwater levels have been disrupted: a groundwater rise is observed in the centre and a piezometric drawdown is observed in the upstream regions. Groundwater quality degradation was registered especially in the centre and downstream zones.
Bresciani, Mariano; Stroppiana, Daniela; Odermatt, Daniel; Morabito, Giuseppe; Giardino, Claudia
2011-08-01
The lakes of the European perialpine region constitute a large water reservoir, which is threatened by the anthropogenic pressure altering water quality. The Water Framework Directive of the European Commission aims to protect water resources and monitoring is seen as an essential step for achieving this goal. Remote sensing can provide frequent data for large scale studies of water quality parameters such as chlorophyll-a (chl-a). In this work we use a dataset of maps of chl-a derived from over 200 MERIS (MEdium Resolution Imaging Spectrometer) satellite images for comparing water quality of 12 perialpine lakes in the period 2003-2009. Besides the different trophic levels of the lakes, results confirm that the seasonal variability of chl-a concentration is particularly pronounced during spring and autumn especially for the more eutrophic lakes. We show that relying on only one sample for the assessment of lake water quality during the season might lead to misleading results and erroneous assignments to quality classes. Time series MERIS data represents a suitable and cost-effective technology to fill this gap, depicting the dynamics of the surface waters of lakes in agreement with the evolution of natural phenomena. Copyright © 2011 Elsevier B.V. All rights reserved.
Water disinfection: microbes versus molecules - an introduction of issues
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fowle, J.R. III, Kopfler, F.C.
If the chemicals used to rid drinking water of disease-causing microbes are themselves potentially harmful, is drinking water safe. What trade-offs are acceptable with respect to microbial versus chemical water quality. This conference deals with current thinking about these topics. The subjects discussed reflect the evolution of thinking, both scientifically and socially, about how best to supply the public with safe, pure potable water. The goal of this paper is to introduce the issues associated with disinfectants and disinfectant by-products in water. This will be done by presenting a historical overview of the use of chemical disinfectants to purify drinkingmore » water and the subsequent awareness of potential health concerns. Historically, the major health issue associated with water has been the demonstrated role that water has played in spreading infectious disease. Waterborne infectious agents remain in the environment, and new ones emerge through evolution of humans and microorganisms and because of changing exposure patterns.« less
NASA Astrophysics Data System (ADS)
La Jeunesse, Isabelle; Sellami, Haykel; Cirelli, Claudia
2014-05-01
The latest reports of the intergovernmental panel on climate change explained that the Mediterranean regions are especially vulnerable to the impacts of climate change. These latest are expected to have strong impacts on the management of water resources and on regional economies. The aim of this paper is to discuss impacts of climate changes on the Thau case study in relation to the evolution of water balance, water uses and adaptation to climate change. The Thau coastal lagoon is located in the Mediterranean coast in south of France in the Languedoc-Roussillon Region. Economic activities are diverse from shellfish farming, fertilizers industries to agriculture and tourism. However, tourism and shellfish farming are of major importance for local economy. If tourism is mainly turned to the Sea coast, shellfishes grow within the lagoon and rely on water quality. Previous studies have demonstrated the link between the coastal lagoon water quality and inputs of freshwater from the catchment. Thus, changes in rainfalls, runoff and water balance would not only affect water uses but also water quality. Climate changes projections are presented following the implementation of 4 downscaled climatic models. Impacts on water balance are modelled with SWAT (Soil Water Assessment Tool) for 2041-2070 compared to the 1971-2000 reference period. The decrease of precipitations and water balance will impact discharges and thus decrease the freshwater inputs to the coastal lagoon. A study of water uses conducted in interactions with stakeholders within the Thau area has permitted to assess both current and evolution of water uses. It has revealed local water resources are depleting while water demand is increasing and is planned to continue to increase in the really near future. To prevent water scarcity events, mainly due to the climate change context, the Regional authorities have connected the catchment to the Rhône river to import water. The conclusion of this study is while expected impacts of climate changes on the Thau system were expected to be linked to water balance depletion in the catchment, the main threats are now linked to the impact on water quality of the introduction of the Rhône river waters within the system. This study is conducted in the CLIMB EU-FP7 project (2010-2014).
Track structure: time evolution from physics to chemistry.
Dingfelder, M
2006-01-01
This review discusses interaction cross sections of charged particles (electrons, protons, light ions) with atoms and molecules. The focus is on biological relevant targets like liquid water which serves as a substitute of soft tissue in most Monte Carlo codes. The spatial distribution of energy deposition patterns by different radiation qualities and their importance to the time evolution from the physical to the chemical stage or radiation response is discussed. The determination of inelastic interaction cross sections for charged particles in condensed matter is discussed within the relativistic plane-wave Born approximation and semi-empirical models. The dielectric-response-function of liquid water is discussed.
NASA Astrophysics Data System (ADS)
Rook, S. P.; Vidon, P.; Walter, M. T.
2011-12-01
The management of riparian buffer strips is often regarded as one of the most economical and sustainable methods of managing non-point source pollution and water quality. However, current riparian management often follows a 'one size fits all' design, which fails to recognize the complexity of the many biogeochemical processes that regulate pollutant transformation and retention in these systems. This study addresses two critical gaps in knowledge: (1) How carbon, nitrogen, phosphorous, and iron cycles interact with one another (rather than individually). (2) How stream channel geometry and evolution regulate these nutrient cycles and greenhouse gas (GHG) dynamics in the near stream zone. This project specifically explores the hydrological and biogeochemical functioning of riparian zones across a gradient of stream meander evolution stages, with the primary goal of understanding and predicting potential interactions between nutrient dynamics in these systems. Key research questions include: (1) How does stream meander curvature affect riparian zone hydrology? (2) How does stream meander curvature influence riparian zone biogeochemistry? (3) What relationships exist among N, P, Fe, and GHG dynamics? We instrumented three riparian sites near Ithaca, NY, with a dense network of wells, piezometers, and static chambers. These sites represent three riparian zones along three evolution stages of stream meanders: an inner meander, a straight stream section, and an outer bend of the stream with an oxbow lake formation. In spring through fall 2011, water samples and gas samples were collected at a tri-weekly bases at each of the three sites. Water samples were analyzed for oxidation-reduction potential, dissolved oxygen, temperature, FeII/FeIII, nutrients (NO3-, NH4+, PO43-) and dissolved organic carbon (DOC). GHG fluxes at the soil-atmosphere interface were measured for N2O, CO2, and CH4 gases. We predict that stream curvature will significantly affect groundwater flow direction in the riparian zones. Owing to more prolonged saturation, we expect that the oxbow setting will exhibit anoxic conditions, and associated biogeochemistry. Finally, we hypothesize clear relationships among N, P, Fe, and GHG dynamics. In areas of significant denitrification, we expect to see an increase in Fe reduction, PO43- release, N2O emission, and CH4 emission, and a decrease in CO2 emission. Quantifying these interactions will enhance our ability to model riparian biogeochemical processes, promote water quality, and comprehend to what extent the promotion of riparian zones for nitrate removal is done at the expense of air quality (with respect to GHG emissions) and/or water quality (with respect to P).
Zhang, Xiaoying; Miao, Jinjie; Hu, Bill X; Liu, Hongwei; Zhang, Hanxiong; Ma, Zhen
2017-09-01
The aquifer in the coastal area of the Laizhou Bay is affected by salinization processes related to intense groundwater exploitation for brine resource and for agriculture irrigation during the last three decades. As a result, the dynamic balances among freshwater, brine, and seawater have been disturbed and the quality of groundwater has deteriorated. To fully understand the groundwater chemical distribution and evolution in the regional aquifers, hydrogeochemical and isotopic studies have been conducted based on the water samples from 102 observation wells. Groundwater levels and salinities in four monitoring wells are as well measured to inspect the general groundwater flow and chemical patterns and seasonal variations. Chemical components such as Na + , K + , Ca 2+ , Mg 2+ , Sr 2+ , Cl - , SO 4 2- , HCO 3 - , NO 3 - , F - , and TDS during the same period are analyzed to explore geochemical evolution, water-rock interactions, sources of salt, nitrate, and fluoride pollution in fresh, brackish, saline, and brine waters. The decreased water levels without typical seasonal variation in the southeast of the study area confirm an over-exploitation of groundwater. The hydrogeochemical characteristics indicate fresh-saline-brine-saline transition pattern from inland to coast where evaporation is a vital factor to control the chemical evolution. The cation exchange processes are occurred at fresh-saline interfaces of mixtures along the hydraulic gradient. Meanwhile, isotopic data indicate that the brine in aquifers was either originated from older meteoric water with mineral dissolution and evaporation or repeatedly evaporation of retained seawater with fresher water recharge and mixing in geological time. Groundwater suitability for drinking is further evaluated according to water quality standard of China. Results reveal high risks of nitrate and fluoride contamination. The elevated nitrate concentration of 560 mg/L, which as high as 28 times of the standard content in drinking water is identified in the south region. In addition, the nitrate and ammonia data of the Wei River suggests decreasing nitrification rate in the study area from inland to estuary. High fluoride concentration, larger than 1 mg/L, is also detected in an area of about 50% of the study region. The saltwater intrusion is analyzed to be responsible for part of dissolution of minerals containing fluoride. Therefore, water treatment before drinking is needed in urgent to reduce the health expose risk.
NASA Astrophysics Data System (ADS)
Lapworth, Dan; Das, Prerona; Mukherjee, Abhijit; Petersen, Jade; Gooddy, Daren; Krishan, Gopal
2017-04-01
Groundwater abstracted from aquifers underlying urban centres across India provide a vital source of domestic water. Abstraction from municipal and private supplies is considerable and growing rapidly with ever increasing demand for water from expanding urban populations. This trend is set to continue. The vulnerability of deeper aquifers (typically >100 m below ground) used for domestic water to contamination migration from often heavily contaminated shallow aquifer systems has not been studies in detail in India. This paper focusses on the occurrence of micro-organic contaminants within sedimentary aquifers beneath urban centres which are intensively pumped for drinking water and domestic use. New preliminary results from a detailed case study undertaken across Varanasi, a city with an estimated population of ca. 1.5 million in Uttar Pradesh. Micro -organic groundwater quality status and evolution with depth is investigated through selection of paired shallow and deep sites across the city. These results are considered within the context of paired groundwater residence time tracers within the top 150m within the sedimentary aquifer system. Groundwater emerging contaminant results are compared with surface water quality from the Ganges which is also used for drinking water supply. Broad screening for >800 micro-organic compounds was undertaken. Age dating tools were employed to constrain and inform a conceptual model of groundwater recharge and contaminant evolution within the sedimentary aquifer system.
Banta, J. Ryan; Lambert, Rebecca B.; Slattery, Richard N.; Ockerman, Darwin J.
2012-01-01
During the three surveys, reaches of gaining, losing, or no verifiable change in streamflow were observed in the watersheds in the study area. Reaches of generally consistent gaining or losing streamflow were identified in the Nueces, Frio, and Sabinal River watersheds. The water-quality data indicate that the streamflow, springflow, and groundwater have similar major ion chemical characteristics and generally can be categorized as a calcium-carbonate water type. Those data also indicate that the major ion chemistry was similar during the 2009 and 2010 surveys. Graphical comparisons among ratios of major ions, trace elements, and isotopes (for example, magnesium/calcium ratios to strontium isotopic ratios) indicate that samples collected from each watershed generally clustered together. Determining the source areas and other possible contributors on the basis of these data is not possible because of the small sample size of the water-quality dataset (both in number of samples and spatial distribution of samples). The different relations among the water-quality data indicate that the surface water in the different watersheds is likely influenced by differences in source areas, geochemical evolution, groundwater flow paths and residence time, local stratigraphy, or some combination thereof.
Cocchioni, M; Scuri, S; Morichetti, L; Petrelli, F; Grappasonni, I
2006-01-01
The article underlines the fundamental importance of the protection and promotion of environmental quality for the human health. The evolution of fluvial monitoring techniques is contemplated from chemical and bacteriological analysis until the Index Functional Index (I.F.F). This evolution it's very important because shows a new methodological and cultural maturation that has carried from a anthropocentric vision until an ecocentric vision. The target of this ecological vision is the re-establishment of ecological functionality of the rivers, eliminating the consumer's vision of the water considered only as a usable resource. The importance of an correct monitoring of a river is confirmed, even though the preventive approach priority remains.
A methodology for space-time classification of groundwater quality.
Passarella, G; Caputo, M C
2006-04-01
Safeguarding groundwater from civil, agricultural and industrial contamination is matter of great interest in water resource management. During recent years, much legislation has been produced stating the importance of groundwater as a source for drinking water supplies, underlining its vulnerability and defining the required quality standards. Thus, schematic tools, able to characterise the quality and quantity of groundwater systems, are of very great interest in any territorial planning and/or water resource management activity. This paper proposes a groundwater quality classification method which has been applied to a real aquifer, starting from several studies published by the Italian National Hydrogeologic Catastrophe Defence Group (GNDCI). The methodology is based on the concentration values of several parameters used as indexes of the natural hydro-chemical water condition and of potential man-induced modifications of groundwater quality. The resulting maps, although representative of the quality, do not include any information on its evolution in time. In this paper, this "stationary" classification method has been improved by crossing the quality classes with three indexes of temporal behaviour during recent years. It was then applied to data from monitoring campaigns, performed in spring and autumn, from 1990 to 1996, in the plain of Modena aquifer (central Italy). The results are reported in the form of space-time classification table and maps.
Gronewold, Andrew D; Sobsey, Mark D; McMahan, Lanakila
2017-06-01
For the past several years, the compartment bag test (CBT) has been employed in water quality monitoring and public health protection around the world. To date, however, the statistical basis for the design and recommended procedures for enumerating fecal indicator bacteria (FIB) concentrations from CBT results have not been formally documented. Here, we provide that documentation following protocols for communicating the evolution of similar water quality testing procedures. We begin with an overview of the statistical theory behind the CBT, followed by a description of how that theory was applied to determine an optimal CBT design. We then provide recommendations for interpreting CBT results, including procedures for estimating quantiles of the FIB concentration probability distribution, and the confidence of compliance with recognized water quality guidelines. We synthesize these values in custom user-oriented 'look-up' tables similar to those developed for other FIB water quality testing methods. Modified versions of our tables are currently distributed commercially as part of the CBT testing kit. Published by Elsevier B.V.
NASA Astrophysics Data System (ADS)
El-Sayed, Salah Abdelwahab; Morsy, Samah M.; Zakaria, Khalid M.
2018-06-01
This study addresses the topic of recharge sources and evolution of groundwater in the Atfih area situated in the northeastern part of the Nile Valley, Egypt. Inventory of water wells and collection of groundwater and surface water samples have been achieved. Water samples are analyzed for major ions according to the American Society for Testing and Materials and for the environmental isotopes analysis (oxygen-18 and deuterium) by using a Triple Liquid Isotopic Water Analyzer (Los Gatos). The groundwater is available from the Quaternary aquifer formed mainly of graded sand and gravel interbedded with clay lenses. The hydrogeologic, hydrogeochemical and isotopic investigations indicate the hydrodynamic nature of the aquifer, where different flow paths, recharge sources and evolution mechanisms are distinguished. The directions of groundwater flow are from E, W and S directions suggesting the contribution from Nile River, the Eocene aquifer and the Nile basin, respectively. The groundwater altitudes range from 13 m (MSL) to 44 m (MSL). The hydraulic gradient varies between 0.025 and 0.0015. The groundwater is alkaline (pH > 7) and has salinity ranging from fresh to brackish water (TDS between 528 mg/l and 6070 mg/l). The observed wide range in the ionic composition and water types reflects the effect of different environmental and geological conditions through which the water has flowed. The isotopic compositions of groundwater samples vary between -14.13‰ and +23.56 for δD and between - 2.91‰ and +3.10 for δ18O. The isotopic data indicates that the Quaternary aquifer receive recharge from different sources including the Recent Nile water, surplus irrigation water, old Nile water before the construction of Aswan High Dam, surface runoff of local rains and Eocene aquifer. Evaporation, water rock interaction and mixing between different types of waters are the main processes in the groundwater evolution. Major suggestions are presented to develop the aquifer productivity and to mitigate the deterioration of groundwater quality.
Evolution, ecology and physiology of amphibious killifishes (Cyprinodontiformes).
Turko, A J; Wright, P A
2015-10-01
The order Cyprinodontiformes contains an exceptional diversity of amphibious taxa, including at least 34 species from six families. These cyprinodontiforms often inhabit intertidal or ephemeral habitats characterized by low dissolved oxygen or otherwise poor water quality, conditions that have been hypothesized to drive the evolution of terrestriality. Most of the amphibious species are found in the Rivulidae, Nothobranchiidae and Fundulidae. It is currently unclear whether the pattern of amphibiousness observed in the Cyprinodontiformes is the result of repeated, independent evolutions, or stems from an amphibious common ancestor. Amphibious cyprinodontiforms leave water for a variety of reasons: some species emerse only briefly, to escape predation or capture prey, while others occupy ephemeral habitats by living for months at a time out of water. Fishes able to tolerate months of emersion must maintain respiratory gas exchange, nitrogen excretion and water and salt balance, but to date knowledge of the mechanisms that facilitate homeostasis on land is largely restricted to model species. This review synthesizes the available literature describing amphibious lifestyles in cyprinodontiforms, compares the behavioural and physiological strategies used to exploit the terrestrial environment and suggests directions and ideas for future research. © 2015 The Fisheries Society of the British Isles.
Herrero, Albert; Gutiérrez-Cánovas, Cayetano; Vigiak, Olga; Lutz, Stefanie; Kumar, Rohini; Gampe, David; Huber-García, Verena; Ludwig, Ralf; Batalla, Ramon; Sabater, Sergi
2018-07-15
Multiple abiotic stressors affect the ecological status of water bodies. The status of waterbodies in the Ebro catchment (NE Spain) is evaluated using the biological quality elements (BQEs) of diatoms, invertebrates and macrophytes. The multi-stressor influence on the three BQEs was evaluated using the monitoring dataset available from the catchment water authority. Nutrient concentrations, especially total phosphorus (TP), affected most of the analyzed BQEs, while changes in mean discharge, water temperature, or river morphology did not show significant influences. Linear statistical models were used to evaluate the change of water bodies' ecological status under different combinations of future socioeconomic and climate scenarios. Changes in land use, rainfall, water temperature, mean discharge, TP and nitrate concentrations were modeled according to the future scenarios. These revealed an evolution of the abiotic stressors that could lead to a general decrease in the ecosystem quality of water bodies within the Ebro catchment. This deterioration was especially evidenced on the diatoms and invertebrate biological indices, mainly because of the foreseen increase in TP concentrations. Water bodies located in the headwaters were seen as the most sensitive to future changes. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.
Bolasco, Piergiorgio; Contu, Antonio; Meloni, Patrizia; Vacca, Dorio; Murtas, Stefano
2012-01-01
This report attempts to illustrate the positive impact on the quality of dialysis water produced over a 16-year period through the progressive optimization of technological procedures. Fundamental steps included the following: elimination of polyvinyl chloride (PVC), periodical controls, introduction of stainless steel and/or polyethylene polymer and substitution of single-pass reverse osmosis (SRO) with double-pass reverse osmosis (DRO). Daily overnight automatic thermal disinfection of distribution piping rings represented the final step. A dramatic improvement was observed in 645 water samples obtained from distribution piping. The measures applied resulted in a significant improvement of water quality, featuring levels of colony-forming units per milliliter ranging from 247.4 ± 393.7 in the presence of PVC and SRO to 14.1 ± 28.0 with stainless steel and DRO and 2.8 ± 3.2 with cross-linked polyethylene thermoplastic polymer and DRO (p < 0.01). Dialysis water should be viewed by nephrologists as a medicinal product, and every effort should be made to ensure a high-quality liquid. Copyright © 2012 S. Karger AG, Basel.
NASA Astrophysics Data System (ADS)
Habets, F.; Viennot, P.; Thierion, C.; Vergnes, J. P.; Ait Kaci, A.; Caballero, Y.
2015-12-01
The Seine river, located in the temperate climate of northern France and flowing over a large sedimentary basins that hosts multilayer aquifers, is characterized by small temporal variations of its discharge. However, the presence of a megacity (Paris) and a wide area of intensive agriculture combined with climate change puts pressure on the water resources both in terms of quality and quantity. Previous research projects have estimated the impact of climate change on the water resource of the Seine basin, with the uncertainties associated to climate projections, hydrological models or downscaling methods. The water resource was projected to decrease by -14 % ± 10 % in 2050 and -28 +/-16% in 2100. This led to new studies that focus on the combined impact of climate change and adaptations. The tested adaptations are: a reduction of the groundwater abstractions, evolution of land use, development of small dams to « harvest water » or artificial recharge of aquifers. The communication of the results of these projects to stakeholders have led to the development on new indicators that better express the risk on the water resource management, especially for the groundwater. For instance maps of the evolution of piezometric head are difficult to interpret. To better express the risk evolution, a new indicator was defined: the evolution of the groundwater crisis duration, ie, the period when the charge of the aquifer is below the crisis piezometric level defined by the stakeholders. Such crisis piezometric levels are used to help defining the period when the groundwater abstraction should be reduced. Such maps are more efficient to communicate with water resources managers. This communication will focus on the results from the MEDDE Explore 2070 and ANR Oracle projects.
Systems Reliability Framework for Surface Water Sustainability and Risk Management
NASA Astrophysics Data System (ADS)
Myers, J. R.; Yeghiazarian, L.
2016-12-01
With microbial contamination posing a serious threat to the availability of clean water across the world, it is necessary to develop a framework that evaluates the safety and sustainability of water systems in respect to non-point source fecal microbial contamination. The concept of water safety is closely related to the concept of failure in reliability theory. In water quality problems, the event of failure can be defined as the concentration of microbial contamination exceeding a certain standard for usability of water. It is pertinent in watershed management to know the likelihood of such an event of failure occurring at a particular point in space and time. Microbial fate and transport are driven by environmental processes taking place in complex, multi-component, interdependent environmental systems that are dynamic and spatially heterogeneous, which means these processes and therefore their influences upon microbial transport must be considered stochastic and variable through space and time. A physics-based stochastic model of microbial dynamics is presented that propagates uncertainty using a unique sampling method based on artificial neural networks to produce a correlation between watershed characteristics and spatial-temporal probabilistic patterns of microbial contamination. These results are used to address the question of water safety through several sustainability metrics: reliability, vulnerability, resilience and a composite sustainability index. System reliability is described uniquely though the temporal evolution of risk along watershed points or pathways. Probabilistic resilience describes how long the system is above a certain probability of failure, and the vulnerability metric describes how the temporal evolution of risk changes throughout a hierarchy of failure levels. Additionally our approach allows for the identification of contributions in microbial contamination and uncertainty from specific pathways and sources. We expect that this framework will significantly improve the efficiency and precision of sustainable watershed management strategies through providing a better understanding of how watershed characteristics and environmental parameters affect surface water quality and sustainability. With microbial contamination posing a serious threat to the availability of clean water across the world, it is necessary to develop a framework that evaluates the safety and sustainability of water systems in respect to non-point source fecal microbial contamination. The concept of water safety is closely related to the concept of failure in reliability theory. In water quality problems, the event of failure can be defined as the concentration of microbial contamination exceeding a certain standard for usability of water. It is pertinent in watershed management to know the likelihood of such an event of failure occurring at a particular point in space and time. Microbial fate and transport are driven by environmental processes taking place in complex, multi-component, interdependent environmental systems that are dynamic and spatially heterogeneous, which means these processes and therefore their influences upon microbial transport must be considered stochastic and variable through space and time. A physics-based stochastic model of microbial dynamics is presented that propagates uncertainty using a unique sampling method based on artificial neural networks to produce a correlation between watershed characteristics and spatial-temporal probabilistic patterns of microbial contamination. These results are used to address the question of water safety through several sustainability metrics: reliability, vulnerability, resilience and a composite sustainability index. System reliability is described uniquely though the temporal evolution of risk along watershed points or pathways. Probabilistic resilience describes how long the system is above a certain probability of failure, and the vulnerability metric describes how the temporal evolution of risk changes throughout a hierarchy of failure levels. Additionally our approach allows for the identification of contributions in microbial contamination and uncertainty from specific pathways and sources. We expect that this framework will significantly improve the efficiency and precision of sustainable watershed management strategies through providing a better understanding of how watershed characteristics and environmental parameters affect surface water quality and sustainability.
Wise use of water in smart cities - possibilities and limitations
NASA Astrophysics Data System (ADS)
Bąk, Joanna
2018-02-01
The need to save water is due, inter alia, to the paradigm of sustainable development. There are many ways to minimize the consumption of high quality water supplied by the water supply network. These include the simplest way and those complex, requiring additional installation. The lack of water is a big problem, but not only water deficit are dangerous. There is a possibility of secondary water pollution in the water supply network due to changes in network parameters. Changes in these parameters may occur due to reduced demand for water by residents and, as a result, reduced water flow - at the same pipe diameter. The article includes a review with comparative analysis of various classification systems for the tap fittings and other sanitary equipment, such as the Water Efficiency Label (WELL) in Europe or the Water Efficiency Labelling and Standards (WELS) in Australia. Several types of perlators and flow regulators were compared in the research section. This equipment was tested in the household. The possibilities of minimizing water consumption by using them was collated. In addition, the work also analyses the evolution of water consumption in Poland in recent years and their possible relationship with the threats quality of drinking water supplied to consumers.
Simulating the evolution of non-point source pollutants in a shallow water environment.
Yan, Min; Kahawita, Rene
2007-03-01
Non-point source pollution originating from surface applied chemicals in either liquid or solid form as part of agricultural activities, appears in the surface runoff caused by rainfall. The infiltration and transport of these pollutants has a significant impact on subsurface and riverine water quality. The present paper describes the development of a unified 2-D mathematical model incorporating individual models for infiltration, adsorption, solubility rate, advection and diffusion, which significantly improve the current practice on mathematical modeling of pollutant evolution in shallow water. The governing equations have been solved numerically using cubic spline integration. Experiments were conducted at the Hydrodynamics Laboratory of the Ecole Polytechnique de Montreal to validate the mathematical model. Good correspondence between the computed results and experimental data has been obtained. The model may be used to predict the ultimate fate of surface applied chemicals by evaluating the proportions that are dissolved, infiltrated into the subsurface or are washed off.
NASA Astrophysics Data System (ADS)
Morad, Daniel; Nader, Fadi H.; Gasparrini, Marta; Morad, Sadoon; Rossi, Carlos; Marchionda, Elisabetta; Al Darmaki, Fatima; Martines, Marco; Hellevang, Helge
2018-05-01
This petrographic, stable isotopic and fluid inclusion microthermometric study of the Upper Jurassic limestones of an onshore field, Abu Dhabi, United Arab Emirates (UAE) compares diagenesis in flanks and crest of the anticline. The results revealed that the diagenetic and related reservoir quality evolution occurred during three phases, including: (i) eogenesis to mesogenesis 1, during which reservoir quality across the field was either deteriorated or preserved by calcite cementation presumably derived from marine or evolved marine pore waters. Improvement of reservoir quality was due to the formation of micropores by micritization of allochems and creation of moldic/intragranular pores by dissolution of peloids and skeletal fragments. (ii) Obduction of Oman ophiolites and formation of the anticline of the studied field was accompanied by cementation by saddle dolomite and blocky calcite. High homogenization temperatures (125-175 °C) and high salinity (19-26 wt% NaCl eq) of the fluid inclusions, negative δ18OVPDB values (-7.7 to -2.9‰), saddle shape of dolomite, and the presence of exotic cements (i.e. fluorite and sphalerite) suggest that these carbonates were formed by flux of hot basinal brines, probably related to this tectonic compression event. (iii) Mesogenesis 2 during subsidence subsequent to the obduction event, which resulted in extensive stylolitization and cementation by calcite. This calcite cement occluded most of the remaining moldic and inter-/intragranular pores of the flank limestones (water zone) whereas porosity was preserved in the crest. This study contributes to: (1) our understanding of differences in the impact of diagenesis on reservoir quality evolution in flanks and crests of anticlines, i.e. impact of hydrocarbon emplacement on diagenesis, and (2) relating various diagenetic processes to burial history and tectonic events of foreland basins in the Arabian Gulf area and elsewhere.
Use of crayfishes as ecological indicator of water quality in natural lakes and city water grid
NASA Astrophysics Data System (ADS)
Sapunov, Valentin; Fedotov, Valery
2017-04-01
Crayfishes are organisms having strong demands for water quality. Their different species have different ecological limits. Nobel crayfishes Astacus astacus are organisms with narrow ecological limits need clear water that crayfish Pontastacus leptodactylus. Relation between populations of different crayfishes is criteria of water pollution, level of water bodies eutrofication and ecological pressure. Environmental policy of all countries is directed to water supply by drinking water of high quality and preserving the rivers, lakes and seas, suitable for people and wildlife. However, now freshwater reservoirs and water bodies, as well as including centralized drinking water supply, have been exposed to escalating anthropogenic loading, and risk of sudden emergency pollution. Besides, the problem of providing an ecological safety of the population and prevention of threats of ecological crime and terrorism in a zone of drinking water for many countries. The work is devoted to realization and perspectives of use of the biological early warning stations about changes of quality of surface waters, dangerous to a biota, on the basis of bioelectronic systems as elements of environmental monitoring of water areas. Regular monitoring of crayfish population is a way to follow ecological evolution of ponds. Such a monitoring took place in some lakes of Pskov and Leningrad regions. Ecological characters of crayfishes are appropriate for control of water quality in St. Petersburg and Khabarovsk grids. Fore species were used: Procambarus clarcii, Cherax quadricarinatus, A. astacus and P. leptodactilus. The results of the present work and experiments carried out us to conclude that before assessing any concentration of pollutant on water organisms, it is necessary to investigate not only their development, growth and survival, also their adaptive capacity relative to the variation of environmental parameters. Regular monitoring of heart oscillation was base for control of water pollution in real time. Algorithm and equipment for such a monitoring would be demonstrated.
Evaluating and mapping sources and temporary storage areas of sediment
Leslie M. Reid
1982-01-01
Legislation to regulate forest practices, water quality, and management of federal lands has increased the land managers' need for efficient methods of identifying and mapping sources of sediment in forested basins. At the same time, theoretical analysis of landscape evolution has led research geomorphologists to the consideration of many of the same...
NASA Astrophysics Data System (ADS)
Herojeet, Rajkumar; Rishi, Madhuri S.; Lata, Renu; Dolma, Konchok
2017-09-01
Sirsa River flows through the central part of the Nalagarh valley, belongs to the rapid industrial belt of Baddi, Barotiwala and Nalagarh (BBN). The appraisal of surface water quality to ascertain its utility in such ecologically sensitive areas is need of the hour. The present study envisages the application of multivariate analysis, water utility class and conventional graphical representation to reveal the hidden factor responsible for deterioration of water quality and determine the hydrochemical facies and its evolution processes of water types in Nalagarh valley, India. The quality assessment is made by estimating pH, electrical conductivity (EC), total dissolved solids (TDS), total hardness, major ions (Na+, K+, Ca2+, Mg2+, HCO3 -, Cl-, SO4 2-, NO3 - and PO4 3-), dissolved oxygen (DO), biological oxygen demand (BOD) and total coliform (TC) to determine its suitability for drinking and domestic purposes. The parameters like pH, TDS, TH, Ca2+, HCO3 -, Cl-, SO4 2-, NO3 - are within the desirable limit as per Bureau of Indian Standards (Indian Standard Drinking Water Specification (Second Edition) IS:10500. Indian Standard Institute, New Delhi, pp 1-18, 2012). Mg2+, Na+ and K+ ions for pre monsoon and EC during pre and post monsoon at few sites and approx 40% samples of BOD and TC for both seasons exceeds the permissible limits indicate organic contamination from human activities. Water quality classification for designated use indicates that maximum surface water samples are not suitable for drinking water source without conventional treatment. The result of piper trillinear and Chadha's diagram classified majority of surface water samples for both seasons fall in the fields of Ca2+-Mg2+-HCO3 - water type indicating temporary hardness. PCA and CA reveal that the surface water chemistry is influenced by natural factors such as weathering of minerals, ion exchange processes and anthropogenic factors. Thus, the present paper illustrates the importance of multivariate techniques for reliable quality characterization of surface water quality to develop effective pollution reduction strategies and maintain a fine balance between the industrialization and ecological integrity.
NASA Astrophysics Data System (ADS)
Humberston, J. L.; McNinch, J.; Lippmann, T. C.
2016-12-01
The morphology of tidal inlet ebb-shoals varies dynamically over time, particularly in response to large wave events. Understanding which wave qualities most influence shoals' evolution would support advancements in sediment bypassing models as well as targeted maintenance dredging for hydrographic purposes. Unfortunately, shallow and rapidly changing bathymetry, turbid waters and ambiguous wave speeds resulting from multiple shoaling and de-shoaling areas limits many traditional surveying techniques from obtaining the spatial and temporal resolution necessary to effectively characterize shoal development. The Radar Inlet Observing System (RIOS) is a uniquely designed mobile X-band radar system that can be deployed to inlet environments and, using roof-mounted solar panels and an automatically triggered highly efficient diesel generator, run automated hourly collections and wirelessly stream data for up to several months at a time in nearly all weather and water conditions. During 2015 and early 2016, RIOS was deployed to St. Augustine Inlet, FL., New River Inlet, N.C., and Oregon Inlet, N.C. for periods of one to six months to allow for measureable shoal evolution. During deployments, ten minute collections (at 1 Hz) were conducted every hour and the data gridded to a 5m alongshore/cross-shore grid. Raw intensity returns were time-averaged and analyzed to define three metrics of shoal evolution: movement direction, movement velocity and inferred bathymetry. For each location and time period, wave frequencies, wave directions and significant wave heights were collected from the nearest wave-buoy. Time lapse videos of shoal positions were inspected and used in concert with cross-correlations values from each pair of shoal and wave parameters to determine the incident wave qualities most strongly relating to shoal evolution. Preliminary results suggest wave height, more than frequency, controls shoal movement. Wave direction and size collaboratively appear to direct the shoal's alongshore movement direction as well as general trends of morphologic evolution.
NASA Astrophysics Data System (ADS)
Sahu, Paulami; Sikdar, P. K.; Chakraborty, Surajit
2016-02-01
Detailed geochemical analysis of groundwater beneath 1223 km2 area in southern Bengal Basin along with statistical analysis on the chemical data was attempted, to develop a better understanding of the geochemical processes that control the groundwater evolution in the deltaic aquifer of the region. Groundwater is categorized into three types: `excellent', `good' and `poor' and seven hydrochemical facies are assigned to three broad types: `fresh', `mixed' and `brackish' waters. The `fresh' water type dominated with sodium indicates active flushing of the aquifer, whereas chloride-rich `brackish' groundwater represents freshening of modified connate water. The `mixed' type groundwater has possibly evolved due to hydraulic mixing of `fresh' and `brackish' waters. Enrichment of major ions in groundwater is due to weathering of feldspathic and ferro-magnesian minerals by percolating water. The groundwater of Rajarhat New Town (RNT) and adjacent areas in the north and southeast is contaminated with arsenic. Current-pumping may induce more arsenic to flow into the aquifers of RNT and Kolkata cities. Future large-scale pumping of groundwater beneath RNT can modify the hydrological system, which may transport arsenic and low quality water from adjacent aquifers to presently unpolluted aquifer.
Diaz-Espejo, Antonio; Cuevas, María Victoria; Ribas-Carbo, Miquel; Flexas, Jaume; Martorell, Sebastian; Fernández, José Enrique
2012-03-01
Strobilurins are one of the most important classes of agricultural fungicides. In addition to their anti-fungal effect, strobilurins have been reported to produce simultaneous effects in plant physiology. This study investigated whether the use of strobilurin fungicide improved water use efficiency in leaves of grapevines grown under field conditions in a Mediterranean climate in southern Spain. Fungicide was applied three times in the vineyard and measurements of leaf gas exchange, plant water status, abscisic acid concentration in sap ([ABA]), and carbon isotope composition in leaves were performed before and after applications. No clear effect on stomatal conductance, leaf water potential and intrinsic water use efficiency was found after three fungicide applications. ABA concentration was observed to increase after fungicide application on the first day, vanishing three days later. Despite this transient effect, evolution of [ABA] matched well with the evolution of leaf carbon isotope ratio, which can be used as a surrogate for plant water use efficiency. Morning stomatal conductance was negatively correlated to [ABA]. Yield was enhanced in strobilurin treated plants, whereas fruit quality remained unaltered. Published by Elsevier GmbH.
NASA Astrophysics Data System (ADS)
Prokhoda-Shumskikh, L.
2012-04-01
Sochi region is the unique subtropical resort on the Black Sea coast of Russia. Nowadays due to Sochi is the capital of the Olympic game 2014, the government of the Russian Federation accepts the special federal program of Black Sea coast development. Program foresees the existing and creation of new coastal recreational and touristic complexes along the Russian Black Sea coast, such as complex of yacht harbors, water centers (aqua-centers), network of port localities and etc. These coastal projects are different, but the main problems of the environmental impact assessment are the same. The environmental impact and the relative damage should be assessed at the stage of construction as well as at the stage of operation. The key problem for the recreation coastal zone is water quality management. The port localities network as example is considered. To increase the accuracy and informative of forecasts for the coastal zone conditions the system-dynamic model has been developed, what allows to estimate the quality of the sea water, including that in the semi-enclosed coastal water areas with the limited water exchange. The model of water quality in the coastal zone includes the equations of deposit concentration changes and chemical substances evolution in the studied areas. The model incorporates joint description of cycles of two biogenic elements - nitrogen and phosphorus. The system is completely defined by the biogeochemical reactions. The sizes of such water areas allow the applying the full mixing and zero-dimensional models of water quality. The circulation of water inside the area is taken into account additionally. Water exchange in the semi-enclosed coastal water areas is defined by the discharge through the open parts of area border. The novelty of the offered model is its adaptation to the specific conditions of semi-enclosed coastal water areas. At the same time, the model contains details of the biogeochemical processes to complete modelling of the water quality. The developed system dynamics model is realized in the «PowerSim Studio» media. The data of natural measurements of water quality are applied for the model verification, and the correlated numerical results for the Russian Black Sea coast are presented. The main objective of the present paper is to present the actual examples, and to generalise the problems and to discuss the possible approaches of their solution.
NASA Astrophysics Data System (ADS)
Zang, Carina; Dame, Juliane
2017-04-01
Water scarcity concerns not only the limited availability of water but also water of inadequate quality in terms of its designated purposes. Arid regions, such as found in Northern Chile, are especially vulnerable to water contamination, owing to missing dilution. Additionally, the national government of Chile's goal to make the country a globally important food exporter has led to the widespread expansion of agricultural surfaces over the last 20 years, thereby increasing pressure on limited water resources and water quality. Mining, being one of the most important economic sectors in Chile, threatens both surface and groundwater quality. This scenario increases the potential for water use conflicts, which is further compounded by the demand for potable water provided by rivers and groundwater. In order to better understand the role of both physical and human dimensions of water quality, this research uses a socio-hydrological conceptual framework. This approach is used in order to broaden the scope of hydrology to include the anthropogenic impact on the environment. It therefore focuses on human and natural interactions and two-sided feedback loops, instead of purely hydrological cycles. Using the case study of the Rio Huasco watershed changes in water quality, which originate at the nexus of physical parameters, social conflicts and changing land use regimes in Northern Chile, are discussed. This region was chosen as an exemplary case for the development of Chile's arid regions: the valley is located at the southern edge of the Atacama Desert, where water scarcity is a major problem. At present, the watershed is predominantly used for agriculture. Many small farmers still practise strip cultivation, but are pressured to shift towards an international export-orientated future with monocultures. International companies are planning to mine the Pascua Lama Mine, one of the world's biggest gold reserves located in the headwaters of the Rio Huasco. Meanwhile, the problem of scarce water is complicated by the privatization of water rights in Chile. Within the watershed, the amount of sold water rights already exceeds the real water availability by far. An interdisciplinary set of methods was used, including measurements of the chemical and physical parameters of water quality, as well as semi-structured interviews. Water samples across spatial scales were analysed, with the results compared with local people's perceptions of water quality and how this affects their use decisions. The study showed that perceptions of water quality and fear of contamination were influenced by the social conflicts surrounding the controversial construction of the Pascua Lama Mine. The social conflicts were further aggravated by local mistrust towards the multilayered and so-perceived neoliberal and top-down governance structures of water resources in Chile.
Hu, Jun; Dong, Huiyu; Xu, Qiang; Ling, Wencui; Qu, Jiuhui; Qiang, Zhimin
2018-02-01
Switch of source water may induce "red water" episodes. This study investigated the impacts of water quality on iron release, dissolved oxygen consumption (ΔDO), corrosion scale evolution and bacterial community succession in cast iron pipes used for drinking water distribution at pilot scale, and proposed a source water switch strategy accordingly. Three sets of old cast iron pipe section (named BP, SP and GP) were excavated on site and assembled in a test base, which had historically transported blended water, surface water and groundwater, respectively. Results indicate that an increasing Cl - or SO 4 2- concentration accelerated iron release, but alkalinity and calcium hardness exhibited an opposite tendency. Disinfectant shift from free chlorine to monochloramine slightly inhibited iron release, while the impact of peroxymonosulfate depended on the source water historically transported in the test pipes. The ΔDO was highly consistent with iron release in all three pipe systems. The mass ratio of magnetite to goethite in the corrosion scales of SP was higher than those of BP and GP and kept almost unchanged over the whole operation period. Siderite and calcite formation confirmed that an increasing alkalinity and hardness inhibited iron release. Iron-reducing bacteria decreased in the BP but increased in the SP and GP; meanwhile, sulfur-oxidizing, sulfate-reducing and iron oxidizing bacteria increased in all three pipe systems. To avoid the occurrence of "red water", a source water switch strategy was proposed based on the difference between local and foreign water qualities. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Houari, Idir Menad; Nezli, Imed Eddine; Belksier, Mohamed Salah
2018-05-01
The groundwater resources in the Northern Sahara are represented by two superimposed major aquifer systems: the Intercalary Continental (CI) and the Terminal Complex (CT). The waters of these aquifers pose serious physical and chemical quality problems; they are highly mineralized and very hard. The present work aims to describe the water's geochemical evolution of sand groundwater (Mio-Pliocene) of the Terminal Complex in the area of Djamaa, by the research of the relationship between water's chemical composition and lithology of aquifer formations through. The results obtained show that the water's chemistry is essentially governed by the dissolution of evaporate formations, which gives to, waters an excessive mineralization expressed by high concentrations of sulfates, chlorides and sodium.
Predicting water quality changes from artificial recharge sources to nearby wellfields
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moran, J.E.
1998-01-23
Isotope tracer technologies have proven to be powerful tools for addressing questions related to surface water-ground water interactions. The Alameda County Water District artificially recharges tens of thousands of acre-ft of water annually, delivered from Alameda Creek in order to augment dwindling ground water supplies, and to maintain a barrier to seawater intrusion. The authors are using a suite of isotope tracers to track water movement, source characteristics and accompanying water quality changes from ACWD recharge facilities to nearby wells. The data gathered during the three year project will allow quantification of dilution by ambient basin ground water, subsurface travelmore » times, and several key water quality parameters, including degree of degradation of organic compounds, the fate of trace metals during recharge and subsurface transport, and sources and transport of major ions (salts). Reconnaissance work was carried out on naturally occurring isotopes in order to better understand the hydrogeology of the ground water basin. The basin is dissected by the Hayward Fault, and geologic conditions vary greatly on either side of the fault. Stable isotopes of oxygen, carbon, helium and other noble gases, along with radiocarbon and tritium were measured on water samples from production and monitoring wells. The goal of the reconnaissance work was to age date the water at various depths and distances from the recharge ponds, to examine the chemical evolution of the water with age, and to examine the water for source-related variations in isotope composition. Ground water ages were calculated by the tritium-helium method for three production wells in the Peralta-Tyson wellfield (in the Above Hayward Fault sub-basin), and for a monitoring well positioned between the recharge facilities and production wells, screened at three discreet intervals.« less
Tollner, Ernest W.; Douglas-Mankin, Kyle R.
2017-01-01
This article introduces the five papers in the “International Watershed Technology” collection. These papers were selected from 60 technical presentations at the fifth biennial ASABE 21st Century Watershed Technology Conference and Workshop: Improving the Quality of Water Resources at Local, Basin, and Regional Scales, held in Quito, Ecuador, on 3-9 December 2016. The conference focused on solving spatial and temporal water quality and quantity problems and addressed topics such as watershed management in developing countries, aquatic ecology and ecohydrology, ecosystem services, climate change mitigation strategies, flood forecasting, remote sensing, and water resource policy and management. While diverse, the presentation topics reflected the continuing evolution of the “data mining” and “big data” themes of past conferences related to geospatial data applications, with increasing emphasis on practical solutions. The papers selected for this collection represent applications of spatial data analyses toward practical ends with a theme of “tools and techniques for sustainability.” The papers address a range of topics, including the matching of crops with water availability, and assessing the environmental impacts of agricultural production. The papers identify some of the latest tools and techniques for improving sustainability in watershed resource management that are relevant to both developing and developed countries.
Wilson, J P; Fischer, W W
2011-03-01
The core of plant physiology is a set of functional solutions to a tradeoff between CO(2) acquisition and water loss. To provide an important evolutionary perspective on how the earliest land plants met this tradeoff, we constructed a mathematical model (constrained geometrically with measurements of fossils) of the hydraulic resistance of Asteroxylon, an Early Devonian plant. The model results illuminate the water transport physiology of one of the earliest vascular plants. Results show that Asteroxylon's vascular system contains cells with low hydraulic resistances; these resistances are low because cells were covered by scalariform pits, elliptical structures that permit individual cells to have large areas for water to pass from one cell to another. Asteroxylon could move a large amount of water quickly given its large pit areas; however, this would have left these plants particularly vulnerable to damage from excessive evapotranspiration. These results highlight a repeated pattern in plant evolution, wherein the evolution of highly conductive vascular tissue precedes the appearance of adaptations to increase water transport safety. Quantitative insight into the vascular transport of Asteroxylon also allows us to reflect on the quality of CO(2) proxy estimates based on early land plant fossils. Because Asteroxylon's vascular tissue lacked any safety features to prevent permanent damage, it probably used stomatal abundance and behavior to prevent desiccation. If correct, low stomatal frequencies in Asteroxylon reflect the need to limit evapotranspiration, rather than adaptation to high CO(2) concentrations in the atmosphere. More broadly, methods to reveal and understand water transport in extinct plants have a clear use in testing and bolstering fossil plant-based paleoclimate proxies. © 2011 Blackwell Publishing Ltd.
NASA Astrophysics Data System (ADS)
Liang, Yongping; Gao, Xubo; Zhao, Chunhong; Tang, Chunlei; Shen, Haoyong; Wang, Zhiheng; Wang, Yanxin
2018-05-01
In Northern China, karst systems in widely distributed carbonate rocks are one of the most important water supplies for local inhabitants. Constrained by the specific geological and geomorphological conditions, most karst water in this region is discharged as individual or groups of springs. This paper summarizes the characteristics, chemistry, and environmental quality of these karst systems in Northern China. Five structural models of karst water systems were identified based on the relationships between the karst geological strata and karst groundwater flow fields. These specific structural models may closely relate to the attendant environmental geological issues and consistent risks from pollution. Over the past 40 years, the karst water systems in Northern China have suffered from various environmental problems, including deteriorating water quality, the drying up of springs, a continuous decline in the level of karst water, and so on. Based on the field investigation and previous data, a preliminary summary is provided of the environmental problems related to the development and evolutionary trends of karst water in this region. The results highlight the significant challenges associated with karst water, and it is essential that all segments of society be made aware of the situation in order to demand change. In addition, the study provides a scientific basis for the management, protection, and sustainable utilization of karst water resources.
NASA Astrophysics Data System (ADS)
Plampin, Michael R.; Lassen, Rune N.; Sakaki, Toshihiro; Porter, Mark L.; Pawar, Rajesh J.; Jensen, Karsten H.; Illangasekare, Tissa H.
2014-12-01
A primary concern for geologic carbon storage is the potential for leakage of stored carbon dioxide (CO2) into the shallow subsurface where it could degrade the quality of groundwater and surface water. In order to predict and mitigate the potentially negative impacts of CO2 leakage, it is important to understand the physical processes that CO2 will undergo as it moves through naturally heterogeneous porous media formations. Previous studies have shown that heterogeneity can enhance the evolution of gas phase CO2 in some cases, but the conditions under which this occurs have not yet been quantitatively defined, nor tested through laboratory experiments. This study quantitatively investigates the effects of geologic heterogeneity on the process of gas phase CO2 evolution in shallow aquifers through an extensive set of experiments conducted in a column that was packed with layers of various test sands. Soil moisture sensors were utilized to observe the formation of gas phase near the porous media interfaces. Results indicate that the conditions under which heterogeneity controls gas phase evolution can be successfully predicted through analysis of simple parameters, including the dissolved CO2 concentration in the flowing water, the distance between the heterogeneity and the leakage location, and some fundamental properties of the porous media. Results also show that interfaces where a less permeable material overlies a more permeable material affect gas phase evolution more significantly than interfaces with the opposite layering.
NASA Astrophysics Data System (ADS)
Goldenberg, R.; Vigouroux, G.; Chen, Y.; Bring, A.; Kalantari, Z.; Prieto, C.; Destouni, G.
2017-12-01
The Baltic Sea, located in Northern Europe, is one of the world's largest body of brackish water, enclosed and surrounded by nine different countries. The magnitude of climate change may be particularly large in northern regions, and identifying its impacts on vulnerable inland waters and their runoff and nutrient loading to the Baltic Sea is an important and complex task. Exploration of such hydro-climatic impacts is needed to understand potential future changes in physical, ecological and water quality conditions in the regional coastal and marine waters. In this study, we investigate hydro-climatic changes and impacts on the Baltic Sea by synthesizing multi-model climate projection data from the CORDEX regional downscaling initiative (EURO- and Arctic- CORDEX domains, http://www.cordex.org/). We identify key hydro-climatic variable outputs of these models and assess model performance with regard to their projected temporal and spatial change behavior and impacts on different scales and coastal-marine parts, up to the whole Baltic Sea. Model spreading, robustness and impact implications for the Baltic Sea system are investigated for and through further use in simulations of coastal-marine hydrodynamics and water quality based on these key output variables and their change projections. Climate model robustness in this context is assessed by inter-model spreading analysis and observation data comparisons, while projected change implications are assessed by forcing of linked hydrodynamic and water quality modeling of the Baltic Sea based on relevant hydro-climatic outputs for inland water runoff and waterborne nutrient loading to the Baltic sea, as well as for conditions in the sea itself. This focused synthesis and analysis of hydro-climatically relevant output data of regional climate models facilitates assessment of reliability and uncertainty in projections of driver-impact changes of key importance for Baltic Sea physical, water quality and ecological conditions and their future evolution.
Camelid genomes reveal evolution and adaptation to desert environments.
Wu, Huiguang; Guang, Xuanmin; Al-Fageeh, Mohamed B; Cao, Junwei; Pan, Shengkai; Zhou, Huanmin; Zhang, Li; Abutarboush, Mohammed H; Xing, Yanping; Xie, Zhiyuan; Alshanqeeti, Ali S; Zhang, Yanru; Yao, Qiulin; Al-Shomrani, Badr M; Zhang, Dong; Li, Jiang; Manee, Manee M; Yang, Zili; Yang, Linfeng; Liu, Yiyi; Zhang, Jilin; Altammami, Musaad A; Wang, Shenyuan; Yu, Lili; Zhang, Wenbin; Liu, Sanyang; Ba, La; Liu, Chunxia; Yang, Xukui; Meng, Fanhua; Wang, Shaowei; Li, Lu; Li, Erli; Li, Xueqiong; Wu, Kaifeng; Zhang, Shu; Wang, Junyi; Yin, Ye; Yang, Huanming; Al-Swailem, Abdulaziz M; Wang, Jun
2014-10-21
Bactrian camel (Camelus bactrianus), dromedary (Camelus dromedarius) and alpaca (Vicugna pacos) are economically important livestock. Although the Bactrian camel and dromedary are large, typically arid-desert-adapted mammals, alpacas are adapted to plateaus. Here we present high-quality genome sequences of these three species. Our analysis reveals the demographic history of these species since the Tortonian Stage of the Miocene and uncovers a striking correlation between large fluctuations in population size and geological time boundaries. Comparative genomic analysis reveals complex features related to desert adaptations, including fat and water metabolism, stress responses to heat, aridity, intense ultraviolet radiation and choking dust. Transcriptomic analysis of Bactrian camels further reveals unique osmoregulation, osmoprotection and compensatory mechanisms for water reservation underpinned by high blood glucose levels. We hypothesize that these physiological mechanisms represent kidney evolutionary adaptations to the desert environment. This study advances our understanding of camelid evolution and the adaptation of camels to arid-desert environments.
NASA Astrophysics Data System (ADS)
Hnatiuc, B.; Brisset, J. L.; Astanei, D.; Ursache, M.; Mares, M.; Hnatiuc, E.; Felea, C.
2016-12-01
This paper aims to present the evolution of the construction and performances of non-thermal plasma reactors, identifying specific requirements for various known applications, setting out quality indicators that would allow on the one hand comparing devices that use different kinds of electrical discharges but also their rigorous classification by identification of criteria in order to choose the correct cold plasma reactors for a specific application. It briefly comments the post-discharge effect but also the current dilemma on non-thermal plasma direct treatments versus indirect treatments, using plasma activated water (PAW) or plasma activated medium (PAM), promising in cancer treatment.
Lognormal Assimilation of Water Vapor in a WRF-GSI Cycled System
NASA Astrophysics Data System (ADS)
Fletcher, S. J.; Kliewer, A.; Jones, A. S.; Forsythe, J. M.
2015-12-01
Recent publications have shown the viability of both detecting a lognormally-distributed signal for water vapor mixing ratio and the improved quality of satellite retrievals in a 1DVAR mixed lognormal-Gaussian assimilation scheme over a Gaussian-only system. This mixed scheme is incorporated into the Gridpoint Statistical Interpolation (GSI) assimilation scheme with the goal of improving forecasts from the Weather Research and Forecasting (WRF) Model in a cycled system. Results are presented of the impact of treating water vapor as a lognormal random variable. Included in the analysis are: 1) the evolution of Tropical Storm Chris from 2006, and 2) an analysis of a "Pineapple Express" water vapor event from 2005 where a lognormal signal has been previously detected.
Borja, Angel; Bricker, Suzanne B; Dauer, Daniel M; Demetriades, Nicolette T; Ferreira, João G; Forbes, Anthony T; Hutchings, Pat; Jia, Xiaoping; Kenchington, Richard; Carlos Marques, João; Zhu, Changbo
2008-09-01
In recent years, several sets of legislation worldwide (Oceans Act in USA, Australia or Canada; Water Framework Directive or Marine Strategy in Europe, National Water Act in South Africa, etc.) have been developed in order to address ecological quality or integrity, within estuarine and coastal systems. Most such legislation seeks to define quality in an integrative way, by using several biological elements, together with physico-chemical and pollution elements. Such an approach allows assessment of ecological status at the ecosystem level ('ecosystem approach' or 'holistic approach' methodologies), rather than at species level (e.g. mussel biomonitoring or Mussel Watch) or just at chemical level (i.e. quality objectives) alone. Increasing attention has been paid to the development of tools for different physico-chemical or biological (phytoplankton, zooplankton, benthos, algae, phanerogams, fishes) elements of the ecosystems. However, few methodologies integrate all the elements into a single evaluation of a water body. The need for such integrative tools to assess ecosystem quality is very important, both from a scientific and stakeholder point of view. Politicians and managers need information from simple and pragmatic, but scientifically sound methodologies, in order to show to society the evolution of a zone (estuary, coastal area, etc.), taking into account human pressures or recovery processes. These approaches include: (i) multidisciplinarity, inherent in the teams involved in their implementation; (ii) integration of biotic and abiotic factors; (iii) accurate and validated methods in determining ecological integrity; and (iv) adequate indicators to follow the evolution of the monitored ecosystems. While some countries increasingly use the establishment of marine parks to conserve marine biodiversity and ecological integrity, there is awareness (e.g. in Australia) that conservation and management of marine ecosystems cannot be restricted to Marine Protected Areas but must include areas outside such reserves. This contribution reviews the current situation of integrative ecological assessment worldwide, by presenting several examples from each of the continents: Africa, Asia, Australia, Europe and North America.
Esposito, Daniel V; Levin, Igor; Moffat, Thomas P; Talin, A Alec
2013-06-01
Photoelectrochemical (PEC) water splitting represents a promising route for renewable production of hydrogen, but trade-offs between photoelectrode stability and efficiency have greatly limited the performance of PEC devices. In this work, we employ a metal-insulator-semiconductor (MIS) photoelectrode architecture that allows for stable and efficient water splitting using narrow bandgap semiconductors. Substantial improvement in the performance of Si-based MIS photocathodes is demonstrated through a combination of a high-quality thermal SiO2 layer and the use of bilayer metal catalysts. Scanning probe techniques were used to simultaneously map the photovoltaic and catalytic properties of the MIS surface and reveal the spillover-assisted evolution of hydrogen off the SiO2 surface and lateral photovoltage driven minority carrier transport over distances that can exceed 2 cm. The latter finding is explained by the photo- and electrolyte-induced formation of an inversion channel immediately beneath the SiO2/Si interface. These findings have important implications for further development of MIS photoelectrodes and offer the possibility of highly efficient PEC water splitting.
Cayuela, Maria Luz; Sánchez-Monedero, Miguel A; Roig, Asunción
2010-06-01
Two-phase olive mill waste (TPOMW) is a semisolid sludge generated by the olive oil industry. Its recycling as a soil amendment, either unprocessed or composted, is being promoted as a beneficial agricultural practice in the Mediterranean area. One of the major difficulties when composting TPOMW is the compaction of the material due to its dough-like texture, which leads to an inadequate aeration. For this reason, the addition of bulking agents is particularly important to attain a proper composting process. In this study we followed the evolution of two composting mixtures (A and B) prepared by mixing equal amounts of TPOMW and sheep litter (SL) (in a dry weight basis). In pile B grape stalks (GS) were added (10% dry weight) as bulking agent to study their effect on the development of the composting process and the final compost quality. The incorporation of grape stalks to the composting mixture changed the organic matter (OM) degradation dynamics and notably reduced the total amount of lixiviates. The evolution of several maturation indices (C/N, germination index, water soluble carbon, humification indices, C/N in the leachates) showed a faster and improved composting process when GS were added. Moreover, chemical (NH4+, NO3(-), cation exchange capacity, macro and micronutrients, heavy metals) and physical properties (bulk and real densities, air content, total water holding capacity, porosity) of the final composts were analysed and confirmed the superior quality of the compost where GS were added.
Temporal evolution modeling of hydraulic and water quality performance of permeable pavements
NASA Astrophysics Data System (ADS)
Huang, Jian; He, Jianxun; Valeo, Caterina; Chu, Angus
2016-02-01
A mathematical model for predicting hydraulic and water quality performance in both the short- and long-term is proposed based on field measurements for three types of permeable pavements: porous asphalt (PA), porous concrete (PC), and permeable inter-locking concrete pavers (PICP). The model was applied to three field-scale test sites in Calgary, Alberta, Canada. The model performance was assessed in terms of hydraulic parameters including time to peak, peak flow and water balance and a water quality variable (the removal rate of total suspended solids). A total of 20 simulated storm events were used for model calibration and verification processes. The proposed model can simulate the outflow hydrographs with a coefficient of determination (R2) ranging from 0.762 to 0.907, and normalized root-mean-square deviation (NRMSD) ranging from 13.78% to 17.83%. Comparison of the time to peak flow, peak flow, runoff volume and TSS removal rates between the measured and modeled values in model verification phase had a maximum difference of 11%. The results demonstrate that the proposed model is capable of capturing the temporal dynamics of the pavement performance. Therefore, the model has great potential as a practical modeling tool for permeable pavement design and performance assessment.
Huang, Tinglin; Li, Xuan; Rijnaarts, Huub; Grotenhuis, Tim; Ma, Weixing; Sun, Xin; Xu, Jinlan
2014-07-01
Jinpen Reservoir is a deep, stratified reservoir in Shaanxi province, located in a warm temperate zone of Northwest China. Influenced by a temperate monsoon climate, more than 60% of the annual precipitation is concentrated from late summer to autumn (July-September). In recent years, extreme rainfall events occurred more frequently and strongly affected the thermal structure, mixing layer depth and evolution of stratification of Jinpen Reservoir. The reservoir's inflow volume increased sharply after heavy rainfall during the flooding season. Large volumes of inflow induced mixing of stratified water zones in early autumn and disturbed the stratification significantly. A temporary positive effect of such disturbance was the oxygenation of the water close to the bottom of the reservoir, leading to inhibition of the release of nutrients from sediments, especially phosphate. However, the massive inflow induced by storm runoff with increased oxygen-consuming substances led to an increase of the oxygen consumption rate. After the bottom water became anaerobic again, the bottom water quality would deteriorate due to the release of pollutants from sediments. Heavy rainfall events could lead to very high nutrient input into the reservoir due to massive erosion from the surrounding uninhabited steep mountains, and the particulate matter contributed to most nutrient inputs. Reasonably releasing density flow is an effective way to reduce the amounts of particulate associated pollutants entering the reservoir. Significant turbid density flow always followed high rainfall events in Jinpen Reservoir, which not only affected the reservoir water quality but also increased costs of the drinking water treatment plant. Understanding the effects of the storm runoff on the vertical distributions of water quality indicators could help water managers to select the proper position of the intake for the water plant in order to avoid high turbidity outflow. Copyright © 2014 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Nageswara Rao, P. V.; Appa Rao, S.; Subba Rao, N.
2017-05-01
The present study on geochemical evolution of groundwater is taken up to assess the controlling processes of water chemistry in the Western Delta region of the River Godavari (Andhra Pradesh), which is one of the major rice-producing centers in India. The study region is underlain by coarse sand with black clay (buried channels), black silty clay of recent origin (floodplain) and gray/white fine sand of modern beach sediment of marine source (coastal zone), including brown silty clay with fine sand (paleo-beach ridges). Groundwater is mostly brackish and very hard. It is characterized by Na+ > Mg2+ > Ca2+:HCO3 - > Cl- > SO4 2- > NO3 -, Na+ > Mg2+ > Ca2+:Cl- > HCO3 - > SO4 2-, and Mg2+ > Na+ > Ca2+ > or < K+:HCO3 - > Cl- > or > SO4 2- facies. The ionic relations (Ca2+ + Mg2+:HCO3 -, Ca2+ + Mg2+:SO4 2- + HCO3 -, Na+ + K+:TC, Na+ + K+:Cl- + SO4 2-, HCO3 -:TC, HCO3 -:Ca2+ + Mg2+, Na+:Cl- and Na+:Ca2+) indicate that the rock weathering, mineral dissolution, evaporation and ion exchange are the processes to control the aquifer chemistry. Anthropogenic and marine sources are also the supplementary factors for brackish water quality. These observations are further supported by Gibbs mechanisms that control the water chemistry. Thus, the study suggests that the initial quality of groundwater of geogenic origin has been subsequently modified by the influences of anthropogenic and marine sources.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bore II, co-developed by Berkeley Lab researchers Frank Hale, Chin-Fu Tsang, and Christine Doughty, provides vital information for solving water quality and supply problems and for improving remediation of contaminated sites. Termed "hydrophysical logging," this technology is based on the concept of measuring repeated depth profiles of fluid electric conductivity in a borehole that is pumping. As fluid enters the wellbore, its distinct electric conductivity causes peaks in the conductivity log that grow and migrate upward with time. Analysis of the evolution of the peaks enables characterization of groundwater flow distribution more quickly, more cost effectively, and with higher resolutionmore » than ever before. Combining the unique interpretation software Bore II with advanced downhole instrumentation (the hydrophysical logging tool), the method quantifies inflow and outflow locations, their associated flow rates, and the basic water quality parameters of the associated formation waters (e.g., pH, oxidation-reduction potential, temperature). In addition, when applied in conjunction with downhole fluid sampling, Bore II makes possible a complete assessment of contaminant concentration within groundwater.« less
Kinetics and mechanism for degradation of dichlorvos by permanganate in drinking water treatment.
Liu, Chao; Qiang, Zhimin; Adams, Craig; Tian, Fang; Zhang, Tao
2009-08-01
The degradation kinetics and mechanism of dichlorvos by permanganate during drinking water treatment were investigated. The reaction of dichlorvos with permanganate was of second-order overall with negligible pH dependence and an activation energy of 29.5 kJ x mol(-1). At pH 7.0 and 25 degrees C, the rate constant was 25.2+/-0.4M(-1)s(-1). Dichlorvos was first degraded to trimethyl phosphate (TMP) and dimethyl phosphate (DMP) simultaneously which approximately accounted for <5% and >or=95% with respect to phosphorus mass, respectively. Further oxidation of DMP generated a final byproduct, monomethyl phosphate (MMP). MMP was for the first time identified as a major byproduct in chemical oxidation of dichlorvos. The kinetic model based on degradation mechanism and determined reaction rate constants allowed us to predict the evolution of dichlorvos and its byproduct concentrations during permanganate pre-oxidation process at water treatment plants. These results suggest that even though the dichlorvos concentration in surface water complies with the surface water quality standards of China (50 microg L(-1)), its concentration after conventional water treatment will most probably exceed the drinking water quality standards (1 microg L(-1)). Moreover, luminescent bacteria test shows that the acute toxicity of dichlorvos solution evidently increased after permanganate oxidation.
Dhole, Sumit; Stern, Caitlin A; Servedio, Maria R
2018-04-01
The evolution of mating displays as indicators of male quality has been the subject of extensive theoretical and empirical research for over four decades. Research has also addressed the evolution of female mate choice favoring such indicators. Yet, much debate still exists about whether displays can evolve through the indirect benefits of female mate choice. Here, we use a population genetic model to investigate how the extent to which females can directly detect male quality influences the evolution of female choosiness and male displays. We use a continuum framework that incorporates indicator mechanisms that are traditionally modeled separately. Counter to intuition, we find that intermediate levels of direct detection of male quality can facilitate, rather than impede, the evolution of female choosiness and male displays in broad regions of this continuum. We examine how this evolution is driven by selective forces on genetic quality and on the display, and find that direct detection of male quality results in stronger indirect selection favoring female choosiness. Our results imply that displays maybe more likely to evolve when female choosiness has already evolved to discriminate perceptible forms of male quality. They also highlight the importance of considering general female choosiness, as well as preference, in studies of "good genes." © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.
Evolution of helping and harming in heterogeneous groups.
Rodrigues, António M M; Gardner, Andy
2013-08-01
Social groups are often composed of individuals who differ in many respects. Theoretical studies on the evolution of helping and harming behaviors have largely focused upon genetic differences between individuals. However, nongenetic variation between group members is widespread in natural populations, and may mediate differences in individuals' social behavior. Here, we develop a framework to study how variation in individual quality mediates the evolution of unconditional and conditional social traits. We investigate the scope for the evolution of social traits that are conditional on the quality of the actor and/or recipients. We find that asymmetries in individual quality can lead to the evolution of plastic traits with different individuals expressing helping and harming traits within the same group. In this context, population viscosity can mediate the evolution of social traits, and local competition can promote both helping and harming behaviors. Furthermore, asymmetries in individual quality can lead to the evolution of competition-like traits between clonal individuals. Overall, we highlight the importance of asymmetries in individual quality, including differences in reproductive value and the ability to engage in successful social interactions, in mediating the evolution of helping and harming behaviors. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.
Geochemical processes during managed aquifer recharge with desalinated seawater
NASA Astrophysics Data System (ADS)
Ganot, Y.; Holtzman, R.; Weisbrod, N.; Russak, A.; Katz, Y.; Kurtzman, D.
2017-12-01
In this work we study the geochemical processes along the variably-saturated zone during managed aquifer recharge (MAR) with reverse-osmosis desalinated seawater (DSW) to an infiltration pond at the Menashe site, located above the Israeli coastal aquifer. The DSW is post-treated by calcite dissolution (remineralization) in order to meet the Israeli desalinated water quality criteria. Suction cups and monitoring wells inside the pond were used to monitor water quality during two MAR events on 2015 and 2016. Results show that cation exchange is dominant, driven by the high Ca2+ concentration in the post-treated DSW. Stable isotope analysis shows that the composition of the shallow groundwater is similar to the recharged DSW, but with enrichment of Mg2+, Na+, Ca2+ and HCO3-. A calibrated variably-saturated reactive transport model was used to predict the geochemical evolution during 50 years of MAR with two water quality scenarios: post-treated DSW and soft DSW (without post-treatment). The latter scenario was aimed to test soil-aquifer-treatment as an alternative post-treatment technique. In terms of water quality, the results of the two scenarios were found within the range of the desalinated water criteria. Mg2+ enrichment was stable ( 2.5 mg L-1), higher than the zero concentration found in the Israeli DSW. Calcite content reduction was low (<1%) along the variably-saturated profile, after 50 years of MAR. This suggests that using soil-aquifer-treatment as a remineralization technique for DSW is potentially a sustainable practice, which is limited only by the current hydraulic capacity of the Menashe MAR site.
Simple treatment of cotton textile to impart high water repellent properties
NASA Astrophysics Data System (ADS)
Ivanova, N. A.; Zaretskaya, A. K.
2010-12-01
We describe two methods to impart the water repellency for the surface of cotton fabric, using a commercially available and a laboratory synthesized fluoroalkylsiloxanes. To characterize the wettability and the durability of water repellent properties of hydrophobic coating produced, we have studied the advancing water contact angles, rolling angles and the evolution of water contact angle in time during a continuous contact of the surface with the water drop. The quality of the coatings was also assessed after the washing procedure. The analysis of the wettability of hydrophobized fabrics indicated that a better effect, leading to the superhydrophobic state of the surface, was observed when the surface relief of the fabric with the coating is determined by not only the structure and braiding of the fabric, but also the additional elements of texture created by the aggregates of molecules of hydrophobic agent.
Effects of urbanization on groundwater evolution in an urbanizing watershed
NASA Astrophysics Data System (ADS)
Reyes, D.; Banner, J. L.; Bendik, N.
2011-12-01
The Jollyville Plateau Salamander (Eurycea tonkawae), a candidate species for listing under the Endangered Species Act, is endemic to springs and caves within the Bull Creek Watershed of Austin, Texas. Rapid urbanization endangers known populations of this salamander. Conservation strategies lack information on the extent of groundwater contamination from anthropogenic sources in this karst watershed. Spring water was analyzed for strontium (Sr) isotopes and major ions from sites classified as "urban" or "rural" based on impervious cover estimates. Previous studies have shown that the 87Sr/86Sr value of municipal water is significantly higher than values for natural streamwater, which are similar to those for the Cretaceous limestone bedrock of the region's watersheds. We investigate the application of this relationship to understanding the effects of urbanization on groundwater quality. The use of Sr isotopes as hydrochemical tracers is complemented by major ion concentrations, specifically the dominant ions in natural groundwater (Ca and HCO3) and the ions associated with the addition of wastewater (Na and Cl). To identify high priority salamander-inhabited springs for water quality remediation, we explore the processes controlling the chemical evolution of groundwater such as municipal water inputs, groundwater-soil interactions, and solution/dissolution reactions. 87Sr/86Sr values for water samples from within the watershed range from 0.70760 to 0.70875, the highest values corresponding to sites located in the urbanized areas of the watershed. Analyses of the covariation of Sr isotopes with major ion concentrations help elucidate controls on spring water evolution. Springs located in rural portions of the watershed have low 87Sr/86Sr, high concentrations of Ca and HCO3, and low concentrations of Na and Cl. This is consistent with small inputs of municipal water. Three springs located in urban portions of the watershed have high 87Sr/86Sr, low Ca and HCO3, and high Na and Cl. This is consistent with large inputs of municipal water. The other five springs located in urban portions have low 87Sr/86Sr, low concentrations of Ca and HCO3, and high concentrations of Na and Cl. This is reflects a process other than an input of municipal water. Groundwater interaction with soils generally results in higher Na concentrations relative to Ca. 87Sr/86Sr values in this scenario may increase or decrease, depending on the Sr isotope variability of the local soils. Alternatively, precipitation of calcite from groundwater would decrease the concentration of Ca without necessarily decreasing 87Sr/86Sr values. The results suggest more anthropogenic water in urban springs than rural springs. These data serve to identify sources of spring recharge, including better constraints on the location(s) of urban leakage.
Environmental, political, and economic determinants of water quality monitoring in Europe
NASA Astrophysics Data System (ADS)
Beck, Lucas; Bernauer, Thomas; Kalbhenn, Anna
2010-11-01
Effective monitoring is essential for effective pollution control in national and international water systems. To what extent are countries' monitoring choices driven by environmental criteria, as they should be? And to what extent are they also influenced by other factors, such as political and economic conditions? To address these questions, we describe and explain the evolution of one of the most important international environmental monitoring networks in Europe, the one for water quality, in the time period 1965-2004. We develop a geographic information system that contains information on the location of several thousand active monitoring stations in Europe. Using multivariate statistics, we then examine whether and to what extent the spatial and temporal clustering of monitoring intensity is driven by environmental, political, and economic factors. The results show that monitoring intensity is higher in river basins exposed to greater environmental pressure. However, political and economic factors also play a strong role in monitoring decisions: democracy, income, and peer pressure are conducive to monitoring intensity, and monitoring intensity generally increases over time. Moreover, even though monitoring is more intense in international upstream-downstream settings, we observe only a weak bias toward more monitoring downstream of international borders. In contrast, negative effects of European Union (EU) membership and runup to the EU's Water Framework Directive are potential reasons for concern. Our results strongly suggest that international coordination and standardization of water quality monitoring should be intensified. It will be interesting to apply our analytical approach also to other national and international monitoring networks, for instance, the U.S. National Water-Quality Assessment Program or the European Monitoring and Evaluation Program for air pollution.
Pope, L.M.; Mehl, H.E.; Coiner, R.L.
2009-01-01
Because of water quantity and quality concerns within the Ozark aquifer, the State of Kansas in 2004 issued a moratorium on most new appropriations from the aquifer until results were made available from a cooperative study between the U.S. Geological Survey and the Kansas Water Office. The purposes of the study were to develop a regional ground-water flow model and a water-quality assessment of the Ozark aquifer in northwestern Arkansas, southeastern Kansas, southwestern Missouri, and northeastern Oklahoma (study area). In 2006 and 2007, water-quality samples were collected from 40 water-supply wells completed in the Ozark aquifer and spatially distributed throughout the study area. Samples were analyzed for physical properties, dissolved solids and major ions, nutrients, trace elements, and selected isotopes. This report presents the results of the water-quality assessment part of the cooperative study. Water-quality characteristics were evaluated relative to U.S. Environmental Protection Agency drinking-water standards. Secondary Drinking-Water Regulations were exceeded for dissolved solids (11 wells), sulfate and chloride (2 wells each), fluoride (3 wells), iron (4 wells), and manganese (2 wells). Maximum Contaminant Levels were exceeded for turbidity (3 wells) and fluoride (1 well). The Maximum Contaminant Level Goal for lead (0 milligrams per liter) was exceeded in water from 12 wells. Analyses of isotopes in water from wells along two 60-mile long ground-water flow paths indicated that water in the Ozark aquifer was at least 60 years old but the upper age limit is uncertain. The source of recharge water for the wells along the flow paths appeared to be of meteoric origin because of isotopic similarity to the established Global Meteoric Water Line and a global precipitation relation. Additionally, analysis of hydrogen-3 (3H) and carbon-14 (14C) indicated that there was possible leakage of younger ground water into the lower part of the Ozark aquifer. This may be caused by cracks or fissures in the confining unit that separates the upper and lower parts of the aquifer, poorly constructed or abandoned wells, or historic mining activities. Analyses of major ions in water from wells along the flow paths indicated a transition from freshwater in the east to saline water in the west. Generally, ground water along flow paths evolved from a calcium magnesium bicarbonate type to a sodium calcium bicarbonate or a sodium calcium chloride bicarbonate type as water moved from recharge areas in Missouri into Kansas. Much of this evolution occurred within the last 20 to 25 miles of the flow paths along a water-quality transition zone near the Kansas-Missouri State line and west. The water quality of the Kansas part of the Ozark aquifer is degraded compared to the Missouri part. Geophysical and well-bore flow information and depth-dependent water-quality samples were collected from a large-capacity (1,900-2,300 gallons per minute) municipal-supply well to evaluate vertical ground-water flow accretion and variability in water-quality characteristics at different levels. Although the 1,050-foot deep supply well had 500 feet of borehole open to the Ozark aquifer, 77 percent of ground-water flow entering the borehole came from two 20-foot thick rock layers above the 1,000-foot level. For the most part, water-quality characteristics changed little from the deepest sample to the well-head sample, and upwelling of saline water from deeper geologic formations below the well was not evident. However, more saline water may be present below the bottom of the well.
NASA Astrophysics Data System (ADS)
Zhang, Xinyu; An, Li; Yin, Jie; Xi, Pinxian; Zheng, Zhiping; Du, Yaping
2017-03-01
Rational design of high efficient and low cost electrocatalysts for oxygen evolution reaction (OER) plays an important role in water splitting. Herein, a general gelatin-assisted wet chemistry method is employed to fabricate well-defined iron oxy-hydroxides and transitional metal doped iron oxy-hydroxides nanomaterials, which show good catalytic performances for OER. Specifically, the Co-doped iron oxy-hydroxides (Co0.54Fe0.46OOH) show the excellent electrocatalytic performance for OER with an onset potential of 1.52 V, tafel slope of 47 mV/dec and outstanding stability. The ultrahigh oxygen evolution activity and strong durability, with superior performance in comparison to the pure iron oxy-hydroxide (FeOOH) catalysts, originate from the branch structure of Co0.54Fe0.46OOH on its surface so as to provide many active edge sites, enhanced mass/charge transport capability, easy release oxygen gas bubbles, and strong structural stability, which are advantageous for OER. Meanwhile, Co-doping in FeOOH nanostructures constitutes a desirable four-electron pathway for reversible oxygen evolution and reduction, which is potentially useful for rechargeable metal-air batteries, regenerative fuel cells, and other important clean energy devices. This work may provide a new insight into constructing the promising water oxidation catalysts for practical clean energy application.
Zhang, Xinyu; An, Li; Yin, Jie; Xi, Pinxian; Zheng, Zhiping; Du, Yaping
2017-03-08
Rational design of high efficient and low cost electrocatalysts for oxygen evolution reaction (OER) plays an important role in water splitting. Herein, a general gelatin-assisted wet chemistry method is employed to fabricate well-defined iron oxy-hydroxides and transitional metal doped iron oxy-hydroxides nanomaterials, which show good catalytic performances for OER. Specifically, the Co-doped iron oxy-hydroxides (Co 0.54 Fe 0.46 OOH) show the excellent electrocatalytic performance for OER with an onset potential of 1.52 V, tafel slope of 47 mV/dec and outstanding stability. The ultrahigh oxygen evolution activity and strong durability, with superior performance in comparison to the pure iron oxy-hydroxide (FeOOH) catalysts, originate from the branch structure of Co 0.54 Fe 0.46 OOH on its surface so as to provide many active edge sites, enhanced mass/charge transport capability, easy release oxygen gas bubbles, and strong structural stability, which are advantageous for OER. Meanwhile, Co-doping in FeOOH nanostructures constitutes a desirable four-electron pathway for reversible oxygen evolution and reduction, which is potentially useful for rechargeable metal-air batteries, regenerative fuel cells, and other important clean energy devices. This work may provide a new insight into constructing the promising water oxidation catalysts for practical clean energy application.
Isolation of high quality graphene from Ru by solution phase intercalation
NASA Astrophysics Data System (ADS)
Koren, E.; Sutter, E.; Bliznakov, S.; Ivars-Barcelo, F.; Sutter, P.
2013-09-01
We introduce a method for isolating graphene grown on epitaxial Ru(0001)/α-Al2O3. The strong graphene/Ru(0001) coupling is weakened by electrochemically driven intercalation of hydrogen underpotentially deposited in aqueous KOH solution, which allows the penetration of water molecules at the graphene/Ru(0001) interface. Following these electrochemically driven processes, the graphene can be isolated by electrochemical hydrogen evolution and transferred to arbitrary supports. Raman and transport measurements demonstrate the high quality of the transferred graphene. Our results show that intercalation, typically carried out in vacuum, can be extended to solution environments for graphene processing under ambient conditions.
The use of hydrodynamic vortex separators and screening systems to improve water quality.
Andoh, R Y G; Saul, A J
2003-01-01
The paper reviews the evolution of Hydrodynamic Vortex Separators (HDVS) in the context of application as high rate rotary flow separators for achieving water quality improvements to meet with regulatory requirements in Europe and North America. The types of HDVS and their application for the control of wet-weather discharges such as combined sewer overflows (CSOs), sanitary sewer overflows (SSOs) and stormwater are outlined and a number of myths surrounding their use, dispelled. Reference is made to outputs of peer reviewed comprehensive monitoring, evaluation and demonstration projects on pilot and full-scale installations to demonstrate the efficacy and extensive track record of these systems. Recent developments and innovations in HDVS technologies are discussed, focusing on their combined use as solids liquid separators, contact vessels for wastewater disinfection, the incorporation of self-cleansing screening devices for the control of aesthetic pollutants (e.g. floatables) and the use of computational modelling for optimisation.
Zamora, D; Torres, A
2014-01-01
Reliable estimations of the evolution of water quality parameters by using in situ technologies make it possible to follow the operation of a wastewater treatment plant (WWTP), as well as improving the understanding and control of the operation, especially in the detection of disturbances. However, ultraviolet (UV)-Vis sensors have to be calibrated by means of a local fingerprint laboratory reference concentration-value data-set. The detection of outliers in these data-sets is therefore important. This paper presents a method for detecting outliers in UV-Vis absorbances coupled to water quality reference laboratory concentrations for samples used for calibration purposes. Application to samples from the influent of the San Fernando WWTP (Medellín, Colombia) is shown. After the removal of outliers, improvements in the predictability of the influent concentrations using absorbance spectra were found.
Assessing the sampling strategy in the Northwestern Mediterranean Sea
NASA Astrophysics Data System (ADS)
Margirier, Félix; Testor, Pierre; Bosse, Anthony; Heslop, Emma; L'Hévéder, Blandine; Arsouze, Thomas; Houpert, Loic; Mortier, Laurent
2017-04-01
The deployment of numerous autonomous platforms (gliders, argo floats, moorings) added to the repeated ship cruises in the Northwestern Mediterranean Sea account for a considerable data coverage of the area through the past 10 years. In this study, we analyse the in-situ observations' ability to assess for the changes in the Northwester Mediterranean basin water masses properties over time. Comparing the observed time series for the different regions and different water masses to that of a glider simulator in the NEMO-Med12 model, we estimate both the quality of the model and the skill of the in-situ observations in reproducing the evolution of the basin properties.
NASA Astrophysics Data System (ADS)
Seibert, Stephan; Holt, Tobias; Greskowiak, Janek; Freund, Holger; Böttcher, Michael E.; Massmann, Gudrun
2017-04-01
Coastal aquifers play an important role in satisfying the water demands for many people in the world. However, exposition to storm surges, climate change and extensive abstraction pose a threat to current and future use of these valuable water resources in many cases. To mitigate water quality constraints and ensure safe water supply applications, an in-depth understanding of relevant process that determine the water quality is required. We investigated two freshwater reservoirs below the barrier island Spiekeroog, Germany. The main freshwater reservoir is located at the western part of the island, ˜350 years old and has a vertical extension of ˜45m. The other investigated freshwater reservoir is located at the east of Spiekeroog, only a few decades old and has a vertical extension <7m. The ultimate goal of our work is to identify, quantify and model the processes governing the water quality evolution of freshwater reservoirs below barrier islands. During sampling campaigns in 2011, 2014 and 2016, field parameters were measured and samples for major cation and anion analysis were taken from 16 freshwater wells. Additional samples were taken in 2011 (3H-3He, δ18O, δD), 2014 (DOC, HS-, NH4+, phosphate) and 2016 (DOC, HS-, NH4+, phosphate, 3H-3He, δ18O, δD, δ13C-DIC). Based on the collected data, we conceptualized some important hydrogeochemical processes that are potentially relevant at Spiekeroog. This includes cation exchange, calcite dissolution and redox reactions. The expected freshening time of the main aquifer was estimated by means of the retardation formula for sharp fronts and corresponds to ˜880 years. A 1D PHREEQC simulation showed, however, that the effects of ongoing freshening on the present water quality (after ˜350 years) are negligible. Calculated decalcification rates amount to ˜4.4 mm/year which corresponds to ˜1.5 m downward movement of the decalcification front within the last 350 years. pH values ranging between 7.5-8.5 confirm that groundwater at Spiekeroog is in equilibrium with calcite and underline that calcite dissolution is an important process. With respect to the redox system, the data indicates oxygen and nitrate reduction within the first meters of the saturated zone but Mn-Oxide and Fe-Oxide reduction rates seem to be low in the aquifer based on measured dissolved Mn(2+) and Fe(2+) concentrations. The absence of dissolved Fe(2+) could be explained by the formation of iron sulfide minerals which is in agreement with observed sulfate reduction at greater depth indicated by elevated H2S concentrations and PHREEQC speciation calculations.
Role and functions of beneficial microorganisms in sustainable aquaculture.
Zhou, Qunlan; Li, Kangmin; Jun, Xie; Bo, Liu
2009-08-01
This paper aims to review the development of scientific concepts of microecology and ecology of microbes and the role and functions of beneficial microorganisms in aquaculture and mariculture. Beneficial microorganisms play a great role in natural and man-made aquatic ecosystems based on the co-evolution theory in living biosphere on earth. Their functions are to adjust algal population in water bodies so as to avoid unwanted algal bloom; to speed up decomposition of organic matter and to reduce CODmn, NH3-N and NO2-N in water and sediments so as to improve water quality; to suppress fish/shrimp diseases and water-borne pathogens; to enhance immune system of cultured aquatic animals and to produce bioactive compounds such as vitamins, hormones and enzymes that stimulate growth, thus to decrease the FCR of feed.
Brazeau, Randi H.; Edwards, Marc A.
2013-01-01
Abstract Residential water heating is linked to growth of pathogens in premise plumbing, which is the primary source of waterborne disease in the United States. Temperature and disinfectant residual are critical factors controlling increased concentration of pathogens, but understanding of how each factor varies in different water heater configurations is lacking. A direct comparative study of electric water heater systems was conducted to evaluate temporal variations in temperature and water quality parameters including dissolved oxygen levels, hydrogen evolution, total and soluble metal concentrations, and disinfectant decay. Recirculation tanks had much greater volumes of water at temperature ranges with potential for increased pathogen growth when set at 49°C compared with standard tank systems without recirculation. In contrast, when set at the higher end of acceptable ranges (i.e., 60°C), this relationship was reversed and recirculation systems had less volume of water at risk for pathogen growth compared with conventional systems. Recirculation tanks also tended to have much lower levels of disinfectant residual (standard systems had 40–600% higher residual), 4–6 times as much hydrogen, and 3–20 times more sediment compared with standard tanks without recirculation. On demand tankless systems had very small volumes of water at risk and relatively high levels of disinfectant residual. Recirculation systems may have distinct advantages in controlling pathogens via thermal disinfection if set at 60°C, but these systems have lower levels of disinfectant residual and greater volumes at risk if set at lower temperatures. PMID:24170969
Soil properties evolution after irrigation with reclaimed water
NASA Astrophysics Data System (ADS)
Leal, M.; González-Naranjo, V.; de Miguel, A.; Martínez-Hernández, V.; Lillo, J.
2012-04-01
Many arid and semi-arid countries are forced to look for new and alternative water sources. The availability of suitable quality water for agriculture in these regions often is threatened. In this context of water scarcity, the reuse of treated wastewater for crop irrigation could represent a feasible solution. Through rigorous planning and management, irrigation with reclaimed water presents some advantages such as saving freshwater, reducing wastewater discharges into freshwater bodies and decreasing the amount of added fertilizers due to the extra supply of nutrients by reclaimed water. The current study, which involves wastewater reuse in agriculture, has been carried out in the Experimental Plant of Carrión de los Céspedes (Sevile, Spain). Here, two survey parcels equally designed have been cultivated with Jatropha curcas L, a bioenergetic plant and a non-interfering food security crop. The only difference between the two parcels lies on the irrigation water quality: one is irrigated with groundwater and another one with reclaimed water. The main aim of this study focuses on analysing the outstanding differences in soil properties derived from irrigation with two water qualities, due to their implications for plant growth. To control and monitor the soil variables, soil samples were collected before and after irrigation in the two parcels. pH, electrical conductivity, cation exchange capacity, exchangeable cations (Ca2+, Mg2+, Na+ and K+), kjeldahl nitrogen, organic matter content and nutrients (boron, phosphorus, nitrogen, potassium) were measured. Data were statistically analyzed using the R package. To evaluate the variance ANOVA test was used and to obtain the relations between water quality and soil parameters, Pearson correlation coefficient was computed. According to other authors, a decrease in the organic matter content and an increase of parameters such as pH, electrical conductivity and some exchangeable cations were expected. To date and after one year of irrigation, no significant differences have been found among the soil properties of the two parcels. The results show in one hand, a slightly decrease in phosphorus, nitrates and electrical conductivity and on the other hand, an increase of organic matter. These trends should be contrasted by new soil quality measurements. The implications on vegetation growth, oil production and nutrients assimilation derived from the irrigation with reclaimed water should be also evaluated over time.
NASA Astrophysics Data System (ADS)
Honti, Mark; Schuwirth, Nele; Rieckermann, Jörg; Stamm, Christian
2017-03-01
The design and evaluation of solutions for integrated surface water quality management requires an integrated modelling approach. Integrated models have to be comprehensive enough to cover the aspects relevant for management decisions, allowing for mapping of larger-scale processes such as climate change to the regional and local contexts. Besides this, models have to be sufficiently simple and fast to apply proper methods of uncertainty analysis, covering model structure deficits and error propagation through the chain of sub-models. Here, we present a new integrated catchment model satisfying both conditions. The conceptual iWaQa
model was developed to support the integrated management of small streams. It can be used to predict traditional water quality parameters, such as nutrients and a wide set of organic micropollutants (plant and material protection products), by considering all major pollutant pathways in urban and agricultural environments. Due to its simplicity, the model allows for a full, propagative analysis of predictive uncertainty, including certain structural and input errors. The usefulness of the model is demonstrated by predicting future surface water quality in a small catchment with mixed land use in the Swiss Plateau. We consider climate change, population growth or decline, socio-economic development, and the implementation of management strategies to tackle urban and agricultural point and non-point sources of pollution. Our results indicate that input and model structure uncertainties are the most influential factors for certain water quality parameters. In these cases model uncertainty is already high for present conditions. Nevertheless, accounting for today's uncertainty makes management fairly robust to the foreseen range of potential changes in the next decades. The assessment of total predictive uncertainty allows for selecting management strategies that show small sensitivity to poorly known boundary conditions. The identification of important sources of uncertainty helps to guide future monitoring efforts and pinpoints key indicators, whose evolution should be closely followed to adapt management. The possible impact of climate change is clearly demonstrated by water quality substantially changing depending on single climate model chains. However, when all climate trajectories are combined, the human land use and management decisions have a larger influence on water quality against a time horizon of 2050 in the study.
NASA Astrophysics Data System (ADS)
Zhang, T.; Zeng, W. H.; Wang, S. R.; Ni, Z. K.
2013-12-01
Temporal and spatial changes to the water quality of Dianchi Lake in Southwest China were investigated using monthly monitoring data from 2005 to 2012. Based on the analysis of total phosphorus (TP), total nitrogen (TN), and chlorophyll a (Chl a) concentrations, it was determined that, in Caohai Lake, the annual concentrations of these variables ranged from 0.19-1.46, 6.11-16.79, 0.06-0.14 mg L-1, respectively. In addition, the annual concentrations of TP, TN and Chl a in Waihai Lake ranged between 0.13-0.20, 1.82-3.01, 0.04-0.09 mg L-1, respectively. Cluster Analysis (CA) classified the 10 monitoring sites into two groups (group A and group B) based on similarities of water quality characteristics. Our data revealed that the current status of water quality within Caohai Lake was much worse than that of Waihai Lake. Water quality was seriously degraded during the economic boom near the period of the "Eleventh Five-Year Plan" (2005-2010), and gradually improved from 2010 to 2012 because of the "standard emission directive to industry". The main factors that influenced the spatial and temporal changes to water quality were natural factors including lake evolution and regional characteristic as well as human factors such as pollution load into the lake and management strategies that were already adopted. Some activities and regulations were implemented to enhance the lake environment by controlling wastewater emissions and establishing regulations to protect the lakes in the Yunnan Province. However, problems with institutional fragmentation (horizontal and vertical), simple treatment methods, low-intensity investment in pollution control, and lack of meaningful endogenous pollution control strategies were still present in the lake management strategy. To solve these problems, suitable control measures are needed, especially considering the current old-age status of Dianchi Lake. The fundamental improvement of the water quality within Caohai Lake was dependent on the measures taken in the upper reaches of the Caohai Watershed, including further recovery of submerged plants, resource utilization by floating plants and the reinforcement of sediment disposal. Management strategies for endogenous pollution in Waihai Lake were mainly dependent on restocking algae-eating fish and the ecological restoration of macrophytes. In this way, the swamping trend and the ageing process that is occurring in Dianchi Lake can be stunted.
Water Environment Evolution along the China Grand Canal
NASA Astrophysics Data System (ADS)
Mao, F.; Wu, Y. X.; Yang, B. F.; Li, X. J.
2014-03-01
The China Grand Canal is one of the earliest canals in the world, having lasted for nearly 3000 years. Even its section canals have a rich history, such as the North-South Grand Canal that was established during the Sui Dynasty, whereas the Beijing-Hangzhou Canal was excavated during the Yuan Dynasty and the east line of the South-to-North Water Diversion. As one of the longest in the world, the China Grand Canal's total length is over 3500 kilometers. This length includes the navigable, unnavigable, and underground sections. Making the best use of situations and according to local conditions, the Chinese people harmoniously constructed the Beijing-Hangzhou Canal with nature. Tens of millions of workers took nearly 3000 years to complete the great shipping system. Navigable sections still exist for up to 900 kilometers and the volume of freight traffic is approximately 300 million tons. The canal remains the main logistical channel of the North-to-South Coal Transportation, South-to-North Water Diversion, and resources circulation. To date, China is promoting the success of heritage application. Part of these efforts is the declaration of the China Grand Canal as a World Cultural Heritage by 2014. In addition, the east route of the South-to-North Water Transfer project is planned to be navigable by 2016. The ancient Beijing-Hangzhou Grand Canal will usher in the new ecological civilization and cultural revival along the canal. This paper presents technical methods of water environment evolution research on the river system, river, and water quality along the Beijing-Hangzhou Canal through the integration of historical literature and modern remote sensing image data. The study carried out water environment investigation and analysis along the Beijing-Hangzhou canal by using ETM, SPOT image data, and GPS measurement data. Spatial and temporal evolution characteristics and regulations of the Beijing-Hangzhou Grand Canal regional water environment in the span of 3000 years were obtained. As a key national cultural relic, candidate of the world cultural heritage, and route of the South-to-North Water Diversion, the China Great Canal is a worthy subject of a study. Results presented in this paper therefore have high realistic significance.
NASA Astrophysics Data System (ADS)
Bucci, Arianna; Franchino, Elisa; De Luca, Domenico Antonio; Lasagna, Manuela; Malandrino, Mery; Bianco Prevot, Alessandra; Hernández Sac, Humberto Osvaldo; Coyoy, Israel Macario; Sac Escobar, Edwin Osvaldo; Hernández, Ardany
2017-10-01
Improving understanding on groundwater chemistry is a key priority for water supply from groundwater resources, especially in developing countries. A hydrochemical study was performed in an area of SW Guatemala (Samalà River basin), where water supply to population is groundwater-based and no systematic studies on its groundwater resources have been performed so far. Traditional hydrochemical analyses on major ions and some trace elements metals coupled with chemometric approach were performed, including principal component analysis and hierarchical clustering analysis. Results evidence that chemical differentiation is linked to the spatial distribution of sampled waters. The most common hydrochemical facies, bicarbonate calcium and magnesium, is linked to infiltration of meteoric waters in recharge areas represented by highlands surrounding Xela caldera, a wide plateau where most of population is concentrated. This trend undergoes chemical evolution in proximity of active volcanic complexes in the southern area, with enrichment in sulphate, chloride and magnesium. Chemical evolution also occurs towards the centre of Xela caldera due to slow circulation in aquifer and consequent sodium enrichment due to ion exchange with the porous medium. Water quality did not reveal severe concerns, even though some sources of contamination could be identified; in particular, agriculture and urban wastewater could be responsible for observed threshold exceedances in nitrate and lead. This integrated multi-approach to hydrochemical data interpretation yielded to the achievement of important information that poses the basis for future groundwater protection in an area where main water features were almost unknown.
2006-10-16
spawning sites, feeding sites, 20 seasonal wetlands or drylands, water quality or quantity, host species or plant pollinators , geological 21...rufus]). 12 These areas also contain relatively large areas of sensitive plants . 13 3.9.2.9 Significant Ecological Areas found within the R-2515 and...for complete aircraft, avionics systems, and integrated 21 airframe weapons support. Thus, HPM testing would continue the evolution of the primary
Mesozooplankton affinities in a recovering freshwater estuary
NASA Astrophysics Data System (ADS)
Chambord, Sophie; Maris, Tom; Colas, Fanny; Van Engeland, Tom; Sossou, Akoko-C.; Azémar, Frédéric; Le Coz, Maïwen; Cox, Tom; Buisson, Laetitia; Souissi, Sami; Meire, Patrick; Tackx, Michèle
2016-08-01
Water quality of the Scheldt estuary (Belgium/The Netherlands) has considerably improved in recent years, especially in the upstream, freshwater reaches. Within the zooplankton community, the copepod Eurytemora affinis, typically abundant in brackish water and quasi-absent from freshwater before 2007, has since substantially developed in the latter, where it now represents 90% of the crustacean mesozooplankton community. Simultaneously, cyclopoid copepod abundance has greatly decreased, while cladoceran abundance did not change. The study aim was: 1) to verify if the zooplankton community described for the period 2007-2009 by Mialet et al. (2011) has stabilized until present, and 2) to look for the environmental conditions favouring E. affinis development and causing changes in the upstream freshwater zooplankton community. The 2002-2012 temporal evolution of the zooplankton distribution at three stations in the upstream freshwater Scheldt estuary was analyzed. Water quality remained better after 2007 than before, and some factors revealed continuous improvement in annual mean concentrations (e.g. increase in O2, decrease in BOD5 and NH4sbnd N concentration). The increase in oxygen and the decrease in NH4sbnd N concentration, together with low discharge during summer were the main environmental factors explaining the development and timing of E. affinis in the upstream freshwater reach. In this reach, E. affinis maximal abundance is shifted to higher temperatures (summer) compared to its typical maximum spring abundance peak in the brackish zone of the Scheldt estuary and in most temperate estuaries. The changes in zooplankton community followed a temporal and spatial gradient induced by the spatio-temporal evolution of water quality improvement. The most downstream station (3) allowed E. affinis development (oxygen concentration > 4 mg L-1; NH4sbnd N concentration < 2 mg L-1, discharge (Q) < 50 m3 s-1) from 2007 onwards, and this station showed the highest E. affinis and the lowest cyclopoid abundance. At the more upstream stations E. affinis developed later and less strongly, and cyclopoids decreased less in abundance than at station 3. While there may be several explanations for the decrease in cyclopoid abundance (competitive grazing, high predation pressure, NH3sbnd N toxicity, sensitivity to oxygen, etc.), there is no clear cause for their decline. Water quality improvement in the freshwater Scheldt estuary has led to environmental, post-heavy polluted conditions, under which no data on zooplankton populations in this estuary were available. This has indicated a plasticity in the temperature tolerance of E. affinis.
Mas-Pla, Josep; Menció, Anna
2018-04-11
Climate change will affect the dynamics of the hydrogeological systems and their water resources quality; in particular nitrate, which is herein taken as a paradigmatic pollutant to illustrate the effects of climate change on groundwater quality. Based on climatic predictions of temperature and precipitation for the horizon of 2021 and 2050, as well as on land use distribution, water balances are recalculated for the hydrological basins of distinct aquifer systems in a western Mediterranean region as Catalonia (NE Spain) in order to determine the reduction of available water resources. Besides the fact that climate change will represent a decrease of water availability, we qualitatively discuss the modifications that will result from the future climatic scenarios and their impact on nitrate pollution according to the geological setting of the selected aquifers. Climate effects in groundwater quality are described according to hydrological, environmental, socio-economic, and political concerns. Water reduction stands as a major issue that will control stream-aquifer interactions and subsurface recharge, leading to a general modification of nitrate in groundwater as dilution varies. A nitrate mass balance model provides a gross estimation of potential nitrate evolution in these aquifers, and it points out that the control of the fertilizer load will be crucial to achieve adequate nitrate content in groundwater. Reclaimed wastewater stands as local reliable resource, yet its amount will only satisfy a fraction of the loss of available resources due to climate change. Finally, an integrated management perspective is necessary to avoid unplanned actions from private initiatives that will jeopardize the achievement of sustainable water resources exploitation under distinct hydrological scenarios.
Oxidative stress induced by glyphosate-based herbicide on freshwater turtles.
Héritier, Laurent; Duval, David; Galinier, Richard; Meistertzheim, Anne-Leila; Verneau, Olivier
2017-12-01
Freshwater ecosystems face very strong anthropogenic pressures, among which overexploitation, habitat degradation, flow modification, species invasion, and water pollution lead to growing threats on biodiversity. Urbanization through wastewater treatment, industry through the release of inorganic and organic chemicals, and agriculture through the use of pesticides and herbicides are the main factors involved in water pollution. In France, more precisely in the Pyrénées-Orientales department, the poor quality of the watercourses is attributable overall to the use of glyphosate-based herbicides in agricultural activities. Because these chemicals can impact individuals, populations, and biodiversity, we investigated, under experimental conditions, the physiological response of animals facing abiotic contaminants. We selected as a model, juveniles of the freshwater turtle Trachemys scripta elegans. We measured the gene expression and activity of the catalase and superoxide dismutase enzymes as well as the levels of lipid peroxidation, which are all oxidative stress biomarkers, in turtles challenged with high concentrations of glyphosate-based herbicides, on the one hand, and with degraded waters collected from a local watercourse, on the other. We also measured the acetylcholinesterase activity across the same animals. We showed through variations in gene expression and enzyme activity that a glyphosate commercial formulation induced a stress in turtles. A similar outcome was obtained when turtles faced degraded waters. The results indicated that the poor quality of regional waters could be a real threat for animal health. Because turtles are globally less sensitive to contaminants than amphibians, which are lacking in the degraded waters of the Pyrénées-Orientales department, they could constitute an excellent model to follow the evolution of water quality through the study of oxidative stress biomarkers. Environ Toxicol Chem 2017;36:3343-3350. © 2017 SETAC. © 2017 SETAC.
NASA Astrophysics Data System (ADS)
Gulliver, D. M.; Lowry, G. V.; Gregory, K.
2013-12-01
Geological carbon sequestration is likely to be part of a comprehensive strategy to minimize the atmospheric release of greenhouse gasses, establishing a concern of sequestered CO2 leakage into overlying potable aquifers. Leaking CO2 may affect existing biogeochemical processes and therefore water quality. There is a critical need to understand the evolution of CO2 exposed microbial communities that influence the biogeochemistry in these freshwater aquifers. The evolution of microbial ecology for different CO2 exposure concentrations was investigated using fluid-slurry samples obtained from a shallow freshwater aquifer (55 m depth, 0.5 MPa, 22 °C, Escatawpa, MS). The microbial community of well samples upstream and downstream of CO2 injection was characterized. In addition, batch vessel experiments were conducted with the upstream aquifer samples exposed to varying pCO2 from 0% to 100% under reservoir temperature and pressure for up to 56 days. The microbial community of the in situ experiment and the batch reactor experiment were analyzed with 16S rRNA clone libraries and qPCR. In both the in situ experiment and the batch reactor experiment, DNA concentration did not correlate with CO2 exposure. Both the in situ experiment and the batch reactors displayed a changing microbial community with increased CO2 exposure. The well water isolate, Curvibacter, appeared to be the most tolerant genus to high CO2 concentrations in the in situ experiments and to mid-CO2 concentrations in the batch reactors. In batch reactors with pCO2 concentrations higher than experienced in situ (pCO2 = 0.5 MPa), Pseudomonas appeared to be the most tolerant genus. Findings provide insight into a dynamic biogeochemical system that will alter with CO2 exposure. Adapted microbial populations will eventually give rise to the community that will impact the metal mobility and water quality. Knowledge of the surviving microbial populations will enable improved models for predicting the fate of CO2 following leakage and lead to better strategies for ensuring the quality of potable aquifer water.
Recommendations for Cycle II of National Water-Quality Assessment (NAWQA) Program
,; Mallard, Gail E.; Armbruster, Jeffrey T.; Broshears, Robert E.; Evenson, Eric J.; Luoma, Samuel N.; Phillips, Patrick J.; Prince, Keith R.
1999-01-01
The Planning Team for the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program defines a successful NAWQA Program as one that makes a balanced contribution to study-unit issues, national issues, and to the pursuit of scientific knowledge. Using this criterion, NAWQA has been a success. The program has provided important new knowledge and understanding of scientific processes, and insights into the occurrence and distribution of contaminants that have been key to local and national policy decisions. Most of the basic design characteristics of NAWQA's first decade (1991-2000), hereafter called cycle I) remain appropriate as the program enters its second decade (cycle II) in 2001. In cycle II, the program has the opportunity to build on its successful base and to evolve to take advantage of the knowledge generated in cycle I. In addition to this expected evolution, NAWQA must also make some changes to compensate for the fact that program funding has not kept pace with inflation. An important theme for the second cycle of NAWQA will be the integration of knowledge across scales and across disciplines. The question that drove the NAWQA design in the first cycle was "How is water quality related to land use?" Cycle II will build upon what was learned in cycle I and use land-use and water-quality gradients to identify and understand potential sources of various constituents and the processes affecting transport and fate of those constituents and their effects on receptors. The understanding we gain from applying this approach will be relevant to the interests of policymakers, regulatory agencies, and resource managers.
NASA Technical Reports Server (NTRS)
Evans, Diane
2012-01-01
Objective 2.1.1: Improve understanding of and improve the predictive capability for changes in the ozone layer, climate forcing, and air quality associated with changes in atmospheric composition. Objective 2.1.2: Enable improved predictive capability for weather and extreme weather events. Objective 2.1.3: Quantify, understand, and predict changes in Earth s ecosystems and biogeochemical cycles, including the global carbon cycle, land cover, and biodiversity. Objective 2.1.4: Quantify the key reservoirs and fluxes in the global water cycle and assess water cycle change and water quality. Objective 2.1.5: Improve understanding of the roles of the ocean, atmosphere, land and ice in the climate system and improve predictive capability for its future evolution. Objective 2.1.6: Characterize the dynamics of Earth s surface and interior and form the scientific basis for the assessment and mitigation of natural hazards and response to rare and extreme events. Objective 2.1.7: Enable the broad use of Earth system science observations and results in decision-making activities for societal benefits.
QUAL-NET, a high temporal-resolution eutrophication model for large hydrographic networks
NASA Astrophysics Data System (ADS)
Minaudo, Camille; Curie, Florence; Jullian, Yann; Gassama, Nathalie; Moatar, Florentina
2018-04-01
To allow climate change impact assessment of water quality in river systems, the scientific community lacks efficient deterministic models able to simulate hydrological and biogeochemical processes in drainage networks at the regional scale, with high temporal resolution and water temperature explicitly determined. The model QUALity-NETwork (QUAL-NET) was developed and tested on the Middle Loire River Corridor, a sub-catchment of the Loire River in France, prone to eutrophication. Hourly variations computed efficiently by the model helped disentangle the complex interactions existing between hydrological and biological processes across different timescales. Phosphorus (P) availability was the most constraining factor for phytoplankton development in the Loire River, but simulating bacterial dynamics in QUAL-NET surprisingly evidenced large amounts of organic matter recycled within the water column through the microbial loop, which delivered significant fluxes of available P and enhanced phytoplankton growth. This explained why severe blooms still occur in the Loire River despite large P input reductions since 1990. QUAL-NET could be used to study past evolutions or predict future trajectories under climate change and land use scenarios.
Geochemical characterization of shallow ground water in the Eutaw aquifer, Montgomery, Alabama
Robinson, J.L.; Journey, C.A.
2004-01-01
Ground water samples were collected from 30 wells located in, or directly down gradient from, recharge areas of the Eutaw aquifer in Montgomery, Alabama. The major ion content of the water evolves from calcium-sodium-chloride- dominated type in the recharge area to calcium-bicarbonate-dominated type in the confined portion of the aquifer. Ground water in the recharge area was undersaturated with respect to aluminosilicate and carbonate minerals. Ground water in the confined portion of the aquifer was at equilibrium levels for calcite and potassium feldspar. Dissolved oxygen and nitrite-plus-nitrate concentrations decreased as ground water age increased; pH, iron, and sulfate concentrations increased as ground water age increased. Aluminum, copper, and zinc concentrations decreased as ground water age and pH increased. These relations indicate that nitrate, aluminum, copper, and zinc are removed from solution as water moves from recharge areas to the confined areas of the Eutaw aquifer. The natural evolution of ground water quality, which typically increases the pH and decreases the dissolved oxygen content, may be an important limiting factor to the migration of nitrogen based compounds and metals.
Geochemical and microbiological assessment of groundwater status: a case study
NASA Astrophysics Data System (ADS)
Preziosi, E.; Del Bon, A.; Amalfitano, S.; Fazi, S.; Zoppini, A.; Parrone, D.; Ghergo, S.
2012-04-01
The qualitative status of the groundwater resources is drawing increasingly attention in relation to the requirements of the European legislative framework. The monitoring strategies are developed by considering the chemical processes affecting groundwater quality. However, despite the use of biological indicators is a common practice for the qualitative assessment of surface waters, a similar approach is hardly being taken into account by policy makers for ground waters. Aquifers are key environments due to the ecosystem capability to ameliorate water quality, e.g. through the natural biodegradation of chemical contaminants. The objective of this research was to characterize a porous water table aquifer from a geochemical and microbiological point of view, aiming to link the hydrogeochemical properties to distribution patterns of the free-living microbial communities. The broader perspective is to integrate the role of microorganisms in the groundwater evolution processes, with new insights in the knowledge of the different microbial communities inhabiting different aquifer typologies. Moreover, microbiological parameters that could be used as a valuable indicator of groundwater quality are sought. A field-scale analysis was performed along the southern Sabatini Mounts aquifer (Central Italy, 50 sampling sites), in an area of about 340 square km, where Pleistocene volcanic products overlay Pleistocene gravel and silt-clay layers, the latter being much more widespread in the downgradient part of the study area. The selected aquifer is contaminated by natural origin elements such as arsenic and fluoride, as well as by human activities, both diffuse (agriculture) and localized, especially in the downgradient part of the aquifer (e.g. landfills, quarries, oil deposits). The main physicochemical parameters of ground waters were determined in situ (redox status, pH, conductivity, T, DO, alkalinity) and in laboratory by ionic chromatography and mass spectrometry (major and trace elements, including arsenic). Total bacterial abundance and vitality (live/dead cell ratio) was determined by combining Flow Cytometry with a double staining fluorescence assay, while the microbial community composition was analyzed through hybridization techniques (CARD-FISH). The hydrogeochemical characterization defined an arsenic rich, mainly alkaline-earth bicarbonate type, which evolves downgradiently towards a more calcium rich water. The variability of bacterial abundance was nonetheless high and the percentage of dead bacterial cells shows a significant correlation with the arsenic concentration. In addition, differences of the taxa along the flow path were detected with an increasing abundance of Delta-Proteobacteria in the more anoxic sites. Overall, our results highlighted that a multidisciplinary approach, which combines geochemical and microbiological surveys, can describe more appropriately ground water status and the evolution processes in the aquifer.
Changes in sources and storage in a karst aquifer during a transition from drought to wet conditions
Wong, C.I.; Mahler, B.J.; Musgrove, M.; Banner, J.L.
2012-01-01
Understanding the sources and processes that control groundwater compositions and the timing and magnitude of groundwater vulnerability to potential surface-water contamination under varying meteorologic conditions is critical to informing groundwater protection policies and practices. This is especially true in karst terrains, where infiltrating surface water can rapidly affect groundwater quality. We analyzed the evolution of groundwater compositions (major ions and Sr isotopes) during the transition from extreme drought to wetconditions, and used inverse geochemical modeling (PHREEQC) to constrain controls on groundwater compositions during this evolution. Spring water and groundwater from two wells dominantly receiving diffuse and conduit flow (termed diffuse site and conduit site, respectively) in the Barton Springs segment of the Edwards aquifer (central Texas, USA) and surface water from losing streams that recharge the aquifer were sampled every 3–4 weeks during November 2008–March 2010. During this period, water compositions at the spring and conduit sites changed rapidly but there was no change at the diffuse site, illustrating the dual nature (i.e., diffuse vs. conduit) of flow in this karst system. Geochemical modeling demonstrated that, within a month of the onset of wetconditions, the majority of spring water and groundwater at the conduit site was composed of surface water, providing quantitative information on the timing and magnitude of the vulnerability of groundwater to potential surface-water contamination. The temporal pattern of increasing spring discharge and changing pattern of covariation between spring discharge and surface-water (steam) recharge indicates that that there were two modes of aquifer response—one with a small amount of storage and a second that accommodates more storage.
NASA Astrophysics Data System (ADS)
Baran, Nicole; Petelet-Giraud, Emmanuelle; Saplairoles, Maritxu
2015-04-01
Groundwater quality is increasingly monitored in Europe where various levels of nitrate and pesticide and/or metabolite contamination have been demonstrated (Loos et al., 2010, Stuart et al., 2012). The Groundwater Daughter Directive (2006/118/EC) to Water Framework Directive (WFD) particularly requires measures to prevent or limit inputs of pollutants into groundwater and compliance with good chemical status criteria (based on EU standards of nitrate and pesticides). The WFD mentioned the need to protect groundwater but also to have a particular regard to its impact and interrelationship with associated surface waters and directly dependent terrestrial Ecosystems. The Ariège river basin (SW France - 538 km²) is an alluvial plain under high agricultural pressure leading to a contamination of the aquifer by several pesticides and metabolites (Amalric et al., 2013). The Crieu is an allochtone river, crossing the plain (~ 10 km length) before joining the Ariège River. The Crieu is often dry in its middle section suggesting water leakage from surface water towards groundwater. At the opposite, the permanent flow observed downstream suggests an input of groundwater into surface water. In May 2014, while the Crieu flow was continuous through the plain, 7 river samples were collected and analyzed for pesticides, major ions, strontium concentration and isotopes. In situ measurements of electric conductivity were also performed as well as flow gauging. Two groundwaters close to the river were also sampled. The flow gauging measurements show a decreasing river discharge in the central area of the Crieu River, suggesting surface water leakage towards groundwater. Nevertheless, the electric conductivity increases along the river flow as well as some pesticides and nitrates concentrations. This chemical evolution of the river water is thus inconsistent with a simple water infiltration and another source of dissolved solutes is required to explain the increased of concentration. Finally, downstream the quantified pesticides were different from those observed in the upper part of the Crieu but similar to those observed in groundwater. Sr isotopes together with major elements and Sr concentrations allow to identify 3 distinct end-members to explain the river quality evolution : 1) surface water, 2) groundwater and 3) sub-surface water. On this basis, we first demonstrate that the contribution of the different end-members to the river flow is highly variable from upstream to downstream. Secondly, we evidence water exchanges between the river and the groundwater compartment and vice-versa. The combination of the isotopic and geochemical approaches was essential to understand the complex relations and exchanges between surface and ground-waters occurring in few kilometers along the Crieu River. This understanding allows the comprehension of spatial variability of surface water quality. This is of primary importance when to help water managers to select relevant sampling points to be monitored in the framework of the WFD. Amalric L., et al. (2013). International Journal of Environmental Analytical Chemistry, 93: 1660-1675 Loos R. et al. (2010). Water Research, 44: 4115-4126 Stuart M. et al. (2012). Science of the Total Environment, 416: 1-21.
Hydrogeology and water quality near a solid- and hazardous-waste landfill, Northwood, Ohio
De Roche, J.T.; Breen, K.J.
1989-01-01
Hydrogeology and water quality of ground water and selected streams were evaluated near a landfill in northwestern Ohio. The landfill is used for codisposal of solid and hazardous waste. Water-level and geologic data were collected from 36 wells and 3 surface-water sites during the period November 1983 to November 1985. Water-quality samples were collected from 18 wells and 3 surface-water sites this during this same period. The primary aquifers in the area are the Greenfield Dolomite and underlying Lockport Dolomite of Silurian age. These bedrock carbonates are overlain by two clay tills of Wisconsin age. The tills are capped by a glacial lake clay. The tills generally are saturated, but do not yield sufficient water to be considered an aquifer. Two wells in the study area yield water, in part, from discontinuous deposits of outwash sand and gravel at the lower till-bedrock interface. Regional ground-water flow is from southwest to northeast; local flow is influenced by a ground-water mound centered under the northernmost cells of the landfill. Water levels in wells penetrating refuse within the landfill and the presence of leachate seeps indicate that the refuse is saturated. Head relations among the landfill, till, and dolomite aquifer indicate a vertical component of flow downward from the landfill to the dolomite aquifer. Water levels near the landfill fluctuate as much as 14 feet per year, in contrast to fluctuations of less than 3 feet per year in wells upgradient landfill. Ground waters from wells completed in the dolomite aquifer and glacial till were found to have major-iron concentrations controlled, in large part, by reaction with calcite, dolomite, and other minerals in the aquifer. Only minor departures from equilibrium mineral saturation were noted for ground water, except in wells affected by cement/grout contamination. Molal ratios of calcuim:magnesium in ground water suggest a similar chemical evolution of waters throughout the dolomite aquifer in the study area. Stable-isotope ratios of oxygen and hydrogen indicate the source of water in the till unit and dolomite aquifer is atmospheric precipitation. Elevated levels of total dissolved solids, boron, ammonia, and iron in the leachate and in wells downgradient of the landfill may indicate mixing of ground water with leachate. Oxygen and hydrogen stable-isotope ratios were used to differentiate waters from the glacial till and dolomite aquifer. Isotope ratios also show a shift off the local mixing line for leachate and for a well just downgradient from the landfill. The shift to heavier values of o D in the well water may be indicative of leachate mixing with ground water. The effect of this mixing denoted by hydrologic, isotopic, and chemical-quality data is limited mostly to elevated levels of the common ions. Analysis did not indicate significant levels of toxic metals or organic contaminants except phenol, which was present at concentrations of from 1 to 5 micrograms per liter in six wells. Analysis of water-quality data from nearby streams suggest that surface leaching from the landfill does not significantly affect stream-water quality, but may contribute to higher level of trace metals in the streambed sediments.
Byrne, Patrick; Reid, Ian; Wood, Paul J
2013-03-01
Contaminated drainage from metal mines is a serious water-quality problem facing nations that exploit metal mineral resources. Measurements of river hydrochemistry during baseflow are common at mine sites, whilst detailed hydrochemical information regarding stormflow is limited and often confined to a single event. This study investigates the seasonal evolution of stormflow hydrochemistry at an abandoned metal mine in central Wales, UK, and the possible sources and mechanisms of metal release. Significant flushing of metals was observed during stormflow events, resulting in concentrations that severely exceeded water-quality guidelines. The relationship between metal concentrations and river discharge suggests dissolution of efflorescent metal sulphates on the surface of the mine spoil as the principal source of the contamination. High fluxes of Pb during stormflows are linked to extended periods of dry weather prior to storm events that produced water table drawdown and encouraged oxidation of Pb sulphide in the mine spoil. However, some Pb flushing also occurred following wet antecedent conditions. It is suggested that Fe oxide reduction in mine spoil and translatory flows involving metal-rich pore waters results in flushing during wetter periods. Detailed measurements of stormflow hydrochemistry at mine sites are essential for accurate forecasting of long-term trends in metals flux to understand metal sources and mechanisms of release, to assess potential risks to water quality and instream ecology, and to gauge the potential effectiveness of remediation. In order to protect riverine and riparian ecosystems, it is suggested that routine monitoring of stormflows becomes part of catchment management in mining-impacted regions.
NASA Astrophysics Data System (ADS)
Fenocchi, Andrea; Rogora, Michela; Sibilla, Stefano; Ciampittiello, Marzia; Dresti, Claudia
2018-01-01
The impact of air temperature rise is eminent for the large deep lakes in the Italian subalpine district, climate change being caused there by both natural phenomena and anthropogenic greenhouse-gases (GHG) emissions. These oligomictic lakes are experiencing a decrease in the frequency of winter full turnover and an intensification of stability. As a result, hypolimnetic oxygen concentrations are decreasing and nutrients are accumulating in bottom water, with effects on the whole ecosystem functioning. Forecasting the future evolution of the mixing pattern is relevant to assess if a reduction in GHG releases would be able to revert such processes. The study focuses on Lake Maggiore, for which the thermal structure evolution under climate change in the 2016-2085 period was assessed through numerical simulations, performed with the General Lake Model (GLM). Different prospects of regional air temperature rise were considered, given by the Swiss Climate Change Scenarios CH2011. Multiple realisations were performed for each scenario to obtain robust statistical predictions, adopting random series of meteorological data produced with the Vector-Autoregressive Weather Generator (VG). Results show that a reversion in the increasing thermal stability would be possible only if global GHG emissions started to be reduced by 2020, allowing an equilibrium mixing regime to be restored by the end of the twenty-first century. Otherwise, persistent lack of complete-mixing, severe water warming and extensive effects on water quality are to be expected for the centuries to come. These projections can be extended to the other lakes in the subalpine district.
Li, Fei; Yu, Fengshou; Du, Jian; Wang, Yong; Zhu, Yong; Li, Xiaona; Sun, Licheng
2017-10-18
Water splitting mediated by electron-coupled-proton buffer (ECPB) provides an efficient way to avoid gas mixing by separating oxygen evolution from hydrogen evolution in space and time. Though electrochemical and photoelectrochemcial water oxidation have been incorporated in such a two-step water splitting system, alternative ways to reduce the cost and energy input for decoupling two half-reactions are desired. Herein, we show the feasibility of photocatalytic oxygen evolution in a powder system with BiVO 4 as a photocatalyst and polyoxometalate H 3 PMo 12 O 40 as an electron and proton acceptor. The resulting reaction mixture was allowed to be directly used for the subsequent hydrogen evolution with the reduced H 3 PMo 12 O 40 as electron and proton donors. Our system exhibits excellent stability in repeated oxygen and hydrogen evolution, which brings considerable convenience to decoupled water splitting. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Post-industrial river water quality-Fit for bathing again?
Kistemann, Thomas; Schmidt, Alexandra; Flemming, Hans-Curt
2016-10-01
For the Ruhr River, bathing has been prohibited for decades. However, along with significant improvements of the hygienic water quality, there is an increasing demand of using the river for recreational purposes, in particular for bathing. In the "Safe Ruhr" interdisciplinary research project, demands, options and chances for lifting the bathing ban for the Ruhr River were investigated. As being the prominent reason for persisting recreational restrictions, microbiological water quality was in the focus of interest. Not only the faecal indicator organisms (FIOs) as required by the European Bathing Water Directive were considered, but also pathogens such as Salmonella, Pseudomonas aeruginosa, Legionella pneumophila, Campylobacter, Leptospira, enteroviruses and protozoan parasites. In this introductory paper, we firstly relate current recreational desires to historical experiences of river bathing. After recapitulating relevant microbial river contamination sources (predominantly sewage treatment plants, combined sewer overflows, and surface runoffs), we review existing knowledge about the relationships of FIOs and pathogens in rivers designated for recreational purposes, and then trace the evolution, rationale and validity of recreational freshwater quality criteria which are, despite obvious uncertainties, mostly relying on the FIO paradigm. In particular, the representativeness of FIOs is critically discussed. The working programme of Safe Ruhr, aiming at initiating and facilitating a process towards legalisation of Ruhr River bathing, is outlined. Sources of contamination can be technically handled which leaves the actual measures to political decisions. As contaminations are transient, only occasionally exceeding legal limits, a flexible bathing site management, warning bathers of non-safe situations, may amend technical interventions and offer innovative solutions. As a result, a situation-adapted system for lifting of the bathing ban for Ruhr River appears realistic. Copyright © 2016 Elsevier GmbH. All rights reserved.
Geochemical Characterization of the Upper and Middle Floridan Aquifer System, South Florida
NASA Astrophysics Data System (ADS)
Mirecki, J.; Richardson, E.; Bennett, M.; Hendel, J.
2008-05-01
Our study focus is to characterize the water quality and geochemical environment of the Floridan Aquifer System (FAS) throughout the regional flowpath. A synoptic survey of 21 wells (n=15, upper FAS; n=6 middle FAS) was supplemented by additional samples (n=11) obtained during exploratory well development at 4 aquifer storage recovery (ASR) pilot sites. Synoptic survey samples were analyzed intensively, yielding a dataset that consists of major and trace dissolved constituents (including metals), stable isotopes (δ18O, δ13C, δD, δ34S in sulfate and sulfide), carbon species (carbonate alkalinity and organic carbon), uranium-series radionuclides, nutrients, and selected microbes and pathogens. The objectives of this study are three-fold: 1) to provide baseline water-quality and geochemical information prior to initiation of ASR activities that are part of the Comprehensive Everglades Restoration Plan; 2) to quantify the major controls on geochemical evolution along upper and middle FAS flowpaths using geochemical modeling methods; and 3) to identify areas where water- quality may limit the feasibility of ASR methods in the FAS. Preliminary interpretations water quality changes along the regional FAS flowpath can be summarized as follows. Concentrations of dissolved constituents increase from north to south along the flow path; generally, the upper FAS has lower total dissolved solids than the middle FAS at locations where well pairs were analyzed. The redox environment changes from oxic to strongly anoxic, very close to the recharge area. Redox measurements, dissolved iron, sulfide, and sulfur isotope data are consistent with sulfate-reducing conditions. Uranium-series isotope concentrations and activities generally are below regulatory criteria, with few exceptions in both the upper and middle FAS. Areas with greater radionuclide activity occur primarily at distal flowpath locations or at the coast.
Assessing river health in Europe and Switzerland
NASA Astrophysics Data System (ADS)
Milano, Marianne; Chèvre, Nathalie; Reynard, Emmanuel
2017-04-01
River conditions and welfare of aquatic ecosystems are threatened by anthropogenic and climatic changes. The release of personal-care products, pharmaceuticals and crop protection products is increasing and climate change is likely to cause significant changes in hydrological regimes affecting water resources' capacity to dissolve pollutants. Assessing river health, i.e. the ability of a river to support and maintain a balanced ecosystem close to the natural habitat, is thus of major concern to ensure the development of ecosystems and to provide enough clean useable water to users. Such studies involve physical, chemical and biological processes and characteristics. In Europe and Switzerland, standardized procedures have been developed to assess the hydromorphological, ecological and toxicological status of rivers. The European Water Framework Directive sets ecological requirements and chemical guidelines while the Swiss Modular Stepwise Procedure suggests methods to apprehend ecological deficits and promote water management plans. In this study, both procedures were applied and compared in order (i) to address their capacity to follow-up the spatial and temporal variability of the river's water quality and (ii) to identify challenges that still need to be addressed to assess river's health. Applied on the Boiron River (canton of Vaud, Switzerland) for a 11-year period (2005-2015), both frameworks highlight that no section of the river currently meets a good environmental state. This river flows through a diversified agricultural area causing a progressive deterioration of its chemical and biological quality. The two methods also identify two periods of time with significant changes of the river's water quality. The 2009-2011 period is characterized by a significant deterioration of the river's ecological and toxicological state due to severe low flows and an increased use of pesticides. However, since 2013, an improvement in water quality is identified in relationship with spatial planning and landscaping projects and the first Swiss pilot crop protection product control program developed by the canton of Vaud with the support of the Swiss Confederation. Therefore, the Swiss and EU frameworks are useful tools to address the annual evolution of watercourses' quality but major challenges remain. They relate to (i) experts' training and monitoring, (ii) environmental target values and evaluation rules, (iii) the relationships between modules and (iv) the incorporation of water uses.
Tropical organic soils ecosystems in relation to regional water resources in southeast Asia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Armentano, T. V.
1982-01-01
Tropical organic soils have functioned as natural sinks for carbon, nitrogen, slfur and other nutrients for the past 4000 years or more. Topographic evolution in peat swamp forests towards greater oligotrophy has concentrated storage of the limited nutrient stock in surface soils and biota. Tropical peat systems thus share common ecosystem characteristics with northern peat bogs and certain tropical oligotrophic forests. Organic matter accumulation and high cation-exchange-capacity limit nutrient exports from undisturbed organic soils, although nutrient retention declines with increasing eutrophy and wetland productivity. Peat swamps are subject to irreversible degradation if severely altered because disturbance of vegetation, surface peatsmore » and detritus can disrupt nuttrient cycles and reduce forest recovery capacity. Drainage also greatly increases exports of nitrogen, phosphorus and other nutrients and leads to downstream eutrophication and water quality degradation. Regional planning for clean water supplies must recognize the benefits provided by natural peatlands in balancing water supplies and regulating water chemistry.« less
The Evolution of the Quality Agenda in Higher Education: The Politics of Legitimation
ERIC Educational Resources Information Center
Filippakou, Ourania
2017-01-01
Taking the evolution of the quality agenda in the UK as its centrepiece, this article analyses the politics of legitimation accompanying the emergence of quality assurance and the contribution of quality enhancement to the power play therein. This article argues that over the last 25 years the quality agenda has been used as a proxy--a state…
Water and the Interior Structure of Terrestrial Planets and Icy Bodies
NASA Astrophysics Data System (ADS)
Monteux, J.; Golabek, G. J.; Rubie, D. C.; Tobie, G.; Young, E. D.
2018-02-01
Water content and the internal evolution of terrestrial planets and icy bodies are closely linked. The distribution of water in planetary systems is controlled by the temperature structure in the protoplanetary disk and dynamics and migration of planetesimals and planetary embryos. This results in the formation of planetesimals and planetary embryos with a great variety of compositions, water contents and degrees of oxidation. The internal evolution and especially the formation time of planetesimals relative to the timescale of radiogenic heating by short-lived 26Al decay may govern the amount of hydrous silicates and leftover rock-ice mixtures available in the late stages of their evolution. In turn, water content may affect the early internal evolution of the planetesimals and in particular metal-silicate separation processes. Moreover, water content may contribute to an increase of oxygen fugacity and thus affect the concentrations of siderophile elements within the silicate reservoirs of Solar System objects. Finally, the water content strongly influences the differentiation rate of the icy moons, controls their internal evolution and governs the alteration processes occurring in their deep interiors.
Leloup, Maud; Pallier, Virginie; Nicolau, Rudy; Feuillade-Cathalifaud, Geneviève
2015-01-01
Algae and cyanobacteria are important contributors to the natural organic matter (NOM) of eutrophic water resources. The objective of this work is to increase knowledge on the modifications of algal organic matter (AOM) properties in the long term to anticipate blooms footprint in such aquatic environments. The production of AOM from an alga (Euglena gracilis) and a cyanobacteria (Microcystis aeruginosa) was followed up and characterized during the stationary phase and after one year and four months of cultivation, in batch experiments. Specific UV absorbance (SUVA) index, organic matter fractionation according to hydrophobicity and apparent molecular weight were combined to assess the evolution of AOM. A comparison between humic substances (HS) mainly derived from allochthonous origins and AOM characteristics was performed to hypothesize impacts of AOM transformation processes on the water quality of eutrophic water resources. Each AOM fraction underwent a specific evolution pattern, depending on its composition. Impacts of humification-like processes were predominant over release of biopolymers due to cells decay and led to an increase in the hydrophobic compounds part and molecular weights over time. However, the hydrophilic fraction remained the major fraction whatever the growth stage. Organic compounds generated by maturation of these precursors corresponded to large and aliphatic structures. PMID:26251898
Integrated approach to monitor water dynamics with drones
NASA Astrophysics Data System (ADS)
Raymaekers, Dries; De Keukelaere, Liesbeth; Knaeps, Els; Strackx, Gert; Decrop, Boudewijn; Bollen, Mark
2017-04-01
Remote sensing has been used for more than 20 years to estimate water quality in the open ocean and study the evolution of vegetation on land. More recently big improvements have been made to extend these practices to coastal and inland waters, opening new monitoring opportunities, eg. monitoring the impact of dredging activities on the aquatic environment. While satellite sensors can provide complete coverage and historical information of the study area, they are limited in their temporal revisit time and spatial resolution. Therefore, deployment of drones can create an added value and in combination with satellite information increase insights in the dynamics and actors of coastal and aquatic systems. Drones have the advantages of monitoring at high spatial detail (cm scale), with high frequency and are flexible. One of the important water quality parameters is the suspended sediment concentration. However, retrieving sediment concentrations from unmanned systems is a challenging task. The sediment dynamics in the port of Breskens, the Netherlands, were investigated by combining information retrieved from different data sources: satellite, drone and in-situ data were collected, analysed and inserted in sediment models. As such, historical (satellite), near-real time (drone) and predictive (sediment models) information, integrated in a spatial data infrastructure, allow to perform data analysis and can support decision makers.
Potable water for a city: a historic perspective from Bruges, Belgium
NASA Astrophysics Data System (ADS)
Vandenbohede, A.; Vandevyvere, E.
2014-06-01
Contributing to the optimisation of drinking-water supplies is a key responsibility for professional hydrogeologists. Thus, it is interesting to look back and put current-day practices in the framework of historic evolution and past achievements. The water supply of Bruges (Belgium), with an innovative supply system already established by the end of the 13th century, forms an interesting case study. The supply system consisted of an underground network of pipes feeding public and private wells. A special construction, the Water House, was built to overcome a topographical height difference. Population growth and industrial expansion during the 19th century increased the water demand and new solutions were necessary. Tap water became available from 1925 onwards and, as a stopgap measure to meet demand, deep groundwater was used. This invoked a lively debate among the city council, scientists and entrepreneurs, whereby both water quality and quantity were discussed. Although based on a lack of modern understanding of the groundwater system, some arguments, both pro or contra, look very familiar to current-day hydrogeologists.
Workshop on Evolution of Martian Volatiles. Part 1
NASA Technical Reports Server (NTRS)
Jakosky, B. (Editor); Treiman, A. (Editor)
1996-01-01
This volume contains papers that were presented on February 12-14, 1996 at the Evolution for Martian Volatiles Workshop. Topics in this volume include: returned Martian samples; acidic volatiles and the Mars soil; solar EUV Radiation; the ancient Mars Thermosphere; primitive methane atmospheres on Earth and Mars; the evolution of Martian water; the role of SO2 for the climate history of Mars; impact crater morphology; the formation of the Martian drainage system; atmospheric dust-water ice Interactions; volatiles and volcanos; accretion of interplanetary dust particles; Mars' ionosphere; simulations with the NASA Ames Mars General Circulation Model; modeling the Martian water cycle; the evolution of Martian atmosphere; isotopic composition; solar occultation; magnetic fields; photochemical weathering; NASA's Mars Surveyor Program; iron formations; measurements of Martian atmospheric water vapor; and the thermal evolution Models of Mars.
Science Standards, Science Achievement, and Attitudes about Evolution
ERIC Educational Resources Information Center
Belin, Charlie M.; Kisida, Brian
2015-01-01
This article explores the relationships between (a) the quality of state science standards and student science achievement, (b) the public's belief in teaching evolution and the quality of state standards, and (c) the public's belief in teaching evolution and student science achievement. Using multiple measures, we find no evidence of a…
Groundwater quality from a part of Prakasam District, Andhra Pradesh, India
NASA Astrophysics Data System (ADS)
Subba Rao, N.
2018-03-01
Quality of groundwater is assessed from a part of Prakasam district, Andhra Pradesh, India. Groundwater samples collected from thirty locations from the study area were analysed for pH, electrical conductivity (EC), total dissolved solids (TDS), calcium (Ca2+), magnesium (Mg2+), sodium (Na+), potassium (K+), bicarbonate ( {HCO}3^{ - } ), chloride (Cl-), sulphate ( {SO}4^{2 - } ), nitrate ( {NO}3^{ - } ) and fluoride (F-). The results of the chemical analysis indicate that the groundwater is alkaline in nature and are mainly characterized by Na+- {HCO}3^{ - } and Na+-Cl- facies. Groundwater chemistry reflects the dominance of rock weathering and is subsequently modified by human activities, which are supported by genetic geochemical evolution and hydrogeochemical relations. Further, the chemical parameters (pH, TDS, Ca2+, Mg2+, Na+, {HCO}3^{ - } , Cl-, {SO}4^{2 - } , {NO}3^{ - } and F-) were compared with the drinking water quality standards. The sodium adsorption ratio, percent sodium, permeability index, residual sodium carbonate, magnesium ratio and Kelly's ratio were computed and USSL, Wilcox and Doneen's diagrams were also used for evaluation of groundwater quality for irrigation. For industrial purpose, the pH, TDS, {HCO}3^{ - } , Cl- and {SO}4^{2 - } were used to assess the impact of incrustation and corrosion activities on metal surfaces. As a whole, it is observed that the groundwater quality is not suitable for drinking, irrigation and industrial purposes due to one or more chemical parameters exceeding their standard limits. Therefore, groundwater management measures were suggested to improve the water quality.
Geochemical evolution of groundwater in the Mud Lake area, eastern Idaho, USA
Rattray, Gordon W.
2015-01-01
Groundwater with elevated dissolved-solids concentrations—containing large concentrations of chloride, sodium, sulfate, and calcium—is present in the Mud Lake area of Eastern Idaho. The source of these solutes is unknown; however, an understanding of the geochemical sources and processes controlling their presence in groundwater in the Mud Lake area is needed to better understand the geochemical sources and processes controlling the water quality of groundwater at the Idaho National Laboratory. The geochemical sources and processes controlling the water quality of groundwater in the Mud Lake area were determined by investigating the geology, hydrology, land use, and groundwater geochemistry in the Mud Lake area, proposing sources for solutes, and testing the proposed sources through geochemical modeling with PHREEQC. Modeling indicated that sources of water to the eastern Snake River Plain aquifer were groundwater from the Beaverhead Mountains and the Camas Creek drainage basin; surface water from Medicine Lodge and Camas Creeks, Mud Lake, and irrigation water; and upward flow of geothermal water from beneath the aquifer. Mixing of groundwater with surface water or other groundwater occurred throughout the aquifer. Carbonate reactions, silicate weathering, and dissolution of evaporite minerals and fertilizer explain most of the changes in chemistry in the aquifer. Redox reactions, cation exchange, and evaporation were locally important. The source of large concentrations of chloride, sodium, sulfate, and calcium was evaporite deposits in the unsaturated zone associated with Pleistocene Lake Terreton. Large amounts of chloride, sodium, sulfate, and calcium are added to groundwater from irrigation water infiltrating through lake bed sediments containing evaporite deposits and the resultant dissolution of gypsum, halite, sylvite, and bischofite.
Hydrogen Isotopic Constraints on the Evolution of Surface and Subsurface Water on Mars
NASA Technical Reports Server (NTRS)
Usui, T.; Kurokawa, H.; Wang, J.; Alexander, C. M. O’D.; Simon, J. I.; Jones, J. H.
2017-01-01
The geology and geomorphology of Mars provide clear evidence for the presence of liquid water on its surface during the Noachian and Hesperien eras (i.e., >3 Ga). In contrast to the ancient watery environment, today the surface of Mars is relatively dry. The current desert-like surface conditions, however, do not necessarily indicate a lack of surface or near-surface water/ice. In fact, massive deposits of ground ice and/or icy sediments have been proposed based on subsurface radar sounder observations. Hence, accurate knowledge of both the evolution of the distribution of water and of the global water inventory is crucial to our understanding of the evolution of the climate and near-surface environments and the potential habitability of Mars. This study presents insights from hydrogen isotopes for the interactive evolution of Martian water reservoirs. In particular, based on our new measurement of the D/H ratio of 4 Ga-old Noachian water, we constrain the atmospheric loss and possible exchange of surface and subsurface water through time.
Evolution of helping and harming in heterogeneous populations.
Rodrigues, António M M; Gardner, Andy
2012-07-01
There has been much interest in understanding how demographic factors can mediate social evolution in viscous populations. Here, we examine the impact of heterogeneity in patch quality--that is, the availability of reproductive resources for each breeder--upon the evolution of helping and harming behaviors. We find that, owing to a cancellation of relatedness and kin competition effects, the evolution of obligate and facultative helping and harming is not influenced by the degree of viscosity in populations characterized by either spatial or temporal heterogeneity in patch quality. However, facultative helping and harming may be favored when there is both spatial and temporal heterogeneity in patch quality, with helping and harming being favored in both high-quality and low-quality patches. We highlight the prospect for using kin selection theory to explain within-population variation in social behavior, and point to the need for further theoretical and empirical investigation of this topic. © 2012 The Author(s).
Hydrochemical and multivariate analysis of groundwater quality in the northwest of Sinai, Egypt.
El-Shahat, M F; Sadek, M A; Salem, W M; Embaby, A A; Mohamed, F A
2017-08-01
The northwestern coast of Sinai is home to many economic activities and development programs, thus evaluation of the potentiality and vulnerability of water resources is important. The present work has been conducted on the groundwater resources of this area for describing the major features of groundwater quality and the principal factors that control salinity evolution. The major ionic content of 39 groundwater samples collected from the Quaternary aquifer shows high coefficients of variation reflecting asymmetry of aquifer recharge. The groundwater samples have been classified into four clusters (using hierarchical cluster analysis), these match the variety of total dissolvable solids, water types and ionic orders. The principal component analysis combined the ionic parameters of the studied groundwater samples into two principal components. The first represents about 56% of the whole sample variance reflecting a salinization due to evaporation, leaching, dissolution of marine salts and/or seawater intrusion. The second represents about 15.8% reflecting dilution with rain water and the El-Salam Canal. Most groundwater samples were not suitable for human consumption and about 41% are suitable for irrigation. However, all groundwater samples are suitable for cattle, about 69% and 15% are suitable for horses and poultry, respectively.
NASA Astrophysics Data System (ADS)
Mau, Yair; Porporato, Amilcare
2017-04-01
We present a model for the dynamics of soil water, salt concentration and exchangeable sodium fraction in the root zone, driven by irrigation water of various qualities and stochastic rainfall. The main nonlinear feedback is the decrease in hydraulic conductivity for low salinity and/or high sodicity levels. The three variables have quite disparate characteristic time scales: soil water can vary two or three orders of magnitude faster than the exchangeable sodium fraction. In certain limiting cases in which the input of water is constant, the system can be simplified by eliminating the equation for soil water, allowing a full description of the dynamics in the two-dimensional salinity-sodicity phase space. We estimate soil structure degradation time scales for high sodium-adsorption-ratio irrigation water, and delineate the regions in the salinity-sodicity phase space where sodium-induced degradation is effectively irreversible. This apparent irreversibility is the result of relatively long evolution time scales with respect to human activity. When we take into account stochastic rainfall—and the accompanying wetting and drying cycles—the system produces a myriad of statistical steady states. This means that equal environmental conditions can produce different outcomes, accessible to each other only by large interventions, such as temporary changes in the quality of irrigation water or one-time amendment use. Our characterization of the dynamics of water and salt in the root zone, and how it depends on environmental parameters, offers us opportunities to control and reclaim degraded states making optimal resource use. We show an example of sodic soil reclamation through calcium-based fertigation, with minimal time (and applied water) expenditure.
Sušnik, Janez; Vamvakeridou-Lyroudia, Lydia S; Savić, Dragan A; Kapelan, Zoran
2012-12-01
A System Dynamics Model (SDM) assessing water scarcity and potential impacts of socio-economic policies in a complex hydrological system is developed. The model, simulating water resources deriving from numerous catchment sources and demand from four sectors (domestic, industrial, agricultural, external pumping), contains multiple feedback loops and sub-models. The SDM is applied to the Merguellil catchment, Tunisia; the first time such an integrated model has been developed for the water scarce Kairouan region. The application represents an early step in filling a critical research gap. The focus of this paper is to a) assess the applicability of SDM for assessment of the evolution of a water-scarce catchment and b) to analyse the current and future behaviour of the catchment to evaluate water scarcity, focusing on understanding trends to inform policy. Baseline results indicate aquifer over-exploitation, agreeing with observed trends. If current policy and social behaviour continue, serious aquifer depletion is possible in the not too distant future, with implications for the economy and environment. This is unlikely to occur because policies preventing depletion will be implemented. Sensitivity tests were carried out to show which parameters most impacted aquifer behaviour. Results show non-linear model behaviour. Some tests showed negligible change in behaviour. Others showed unrealistic exponential changes in demand, revenue and aquifer water volume. Policy-realistic parameters giving the greatest positive impact on model behaviour were those controlling per-capita domestic water demand and the pumped volume to coastal cities. All potentially beneficial policy options should be considered, giving the best opportunity for preservation of Kairouan aquifer water quantity/quality, ecologically important habitats and the agricultural socio-economic driver of regional development. SDM is a useful tool for assessing the potential impacts of possible policy measures with respect to the evolution of water scarcity in critical regions. This work was undertaken for the EC FP7 project 'WASSERMed'. Copyright © 2012 Elsevier B.V. All rights reserved.
Power, Christopher; Ramasamy, Murugan; MacAskill, Devin; Shea, Joseph; MacPhee, Joseph; Mayich, David; Baechler, Fred; Mkandawire, Martin
2017-12-01
Cover systems are commonly placed over waste rock piles (WRPs) to limit atmospheric water and oxygen ingress and control the generation and release of acid mine drainage (AMD) to the receiving environment. Although covers containing geomembranes such as high-density polyethylene (HDPE) exhibit the attributes to be highly effective, there are few, if any, published studies monitoring their performance at full-scale WRPs. In 2011, a HDPE cover was installed over the Scotchtown Summit WRP in Nova Scotia, Canada, and extensive field performance monitoring was conducted over the next five years. A range of parameters within the atmosphere, cover, waste rock, groundwater and surface water, were monitored and integrated into a comprehensive hydrogeochemical conceptual model to assess (i) atmospheric ingress to the waste rock, (ii) waste rock acidity and depletion and (iii) evolution of groundwater and surface water quality. Results demonstrate that the cover is effective and meeting site closure objectives. Depletion in oxygen influx resulted in slower sulphide oxidation and AMD generation, while a significant reduction in water influx (i.e. 512 to 50 mm/year) resulted in diminished AMD release. Consistent improvements in groundwater quality (decrease in sulphate and metals; increase in pH) beneath and downgradient of the WRP were observed. Protection and/or significant improvement in surface water quality was evident in all surrounding watercourses due to the improved groundwater plume and elimination of contaminated runoff over previously exposed waste rock. A variably saturated flow and contaminant transport model is currently being developed to predict long-term cover system performance.
The D/H ratio and the evolution of water in the terrestrial planets.
de Bergh, C
1993-02-01
The presence of liquid water at the surface of the Earth has played a major role in the biological evolution of the Earth. None of the other terrestrial planets--Mercury, Venus and Mars--has liquid water at its surface. However, it has been suggested, since the early seventies, from both geological and atmospheric arguments that, although Venus and Mars are presently devoid of liquid water, their surfaces could have been partially or completely covered by water at some time of their evolution. There are many possible diagnostics of the long-term evolution of the planets, either from the present characteristics of their surfaces or from their present atmospheric compositions. Among them, the present value of the D/H ratio is of particular interest, although its significance in terms of long term evolution has been challenged by some authors. Recent progress has been made in this field. We now have evidence for higher D/H ratios on Mars and Venus than on Earth, with an enrichment factor of the order of 5 on Mars, and about 100 on Venus. Any scenario for the evolution of these planets must take this into The most recent models on the evolution of Mars and Venus are reviewed in light of these new measurements.
NASA Astrophysics Data System (ADS)
Pinault, J.-L.; Berthier, F.
2007-01-01
We propose a methodological approach to characterize the resilience of aquatic ecosystems with respect to the evolution of environmental parameters as well as their aptitude to adapt to forcings. This method that is applied to Lake Annecy, France, proceeds in three stages. First, according to the depth, variations of physicochemical parameters versus time are separated into three components related to (1) energy transfer through the surface of the lake, (2) the flow of rivers and springs that feed the lake, and (3) long-term evolution of the benthic zone as a consequence of mineral and organic matter loads. Second, dynamics of the lake are deduced by analyzing the physicochemical parameter components related to the three boundary conditions. Third, a stochastic process associated with the transfer models aims to characterize the resilience of the lakes according to forcings. For Lake Annecy, whose dynamics are representative of oligotrophic stratified lakes controlled by decarbonation processes where turnover and mixing occurring once a year in winter, the major consequence is the impoverishment of dissolved oxygen in deep water in autumn due to a temperature increase of the surface water in summer. The simulation raises relevant questions about whether a connection exists between physicochemical parameters and global warming, which should not induce harmful consequences on water quality and biodiversity in deep water. This methodological approach is general since it does not use any physical conceptual model to predict the hydrosystem behavior but uses directly observed data.
Mapping groundwater quality distinguishing geogenic and anthropogenic contribution using NBL
NASA Astrophysics Data System (ADS)
Preziosi, Elisabetta; Ducci, Daniela; Condesso de Melo, Maria Teresa; Parrone, Daniele; Sellerino, Mariangela; Ghergo, Stefano; Oliveira, Joana; Ribeiro, Luis
2015-04-01
Groundwaters are threatened by anthropic activities and pollution is interesting a large number of aquifers worldwide. Qualitative and quantitative monitoring is required to assess the status and track its evolution in time and space especially where anthropic pressures are stronger. Up to now, groundwater quality mapping has been performed separately from the assessment of its natural status, i.e. the definition of the natural background level of a particular element in a particular area or groundwater body. The natural background level (NBL) of a substance or element allows to distinguish anthropogenic pollution from contamination of natural origin in a population of groundwater samples. NBLs are the result of different atmospheric, geological, chemical and biological interaction processes during groundwater infiltration and circulation. There is an increasing need for the water managers to have sound indications on good quality groundwater exploitation. Indeed the extension of a groundwater body is often very large, in the order of tens or hundreds of square km. How to select a proper location for good quality groundwater abstraction is often limited to a question of facility for drilling (access, roads, authorizations, etc.) or at the most related to quantitative aspects driven by geophysical exploration (the most promising from a transmissibility point of view). So how to give indications to the administrators and water managers about the exploitation of good quality drinking water? In the case of anthropic contamination, how to define which area is to be restored and to which threshold (e.g. background level) should the concentration be lowered through the restoration measures? In the framework of a common project between research institutions in Italy (funded by CNR) and Portugal (funded by FCT), our objective is to establish a methodology aiming at merging together 1) the evaluation of NBL and 2) the need to take into account the drinking water standards with a spatial analysis. We compare diverse case studies using geochemical maps built by kriging in which we interpolate the conditional probability of exceeding the reference value (i.e. the drinking water standard) OR the local natural background level. The resulting maps provide a useful reference for management purposes.
Bee guide to complying with the Safe Drinking Water Act. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garland, J.G.; Acker, A.M.
This report provides current information on the Safe Drinking Water Act and recent amendments. The report describes the evolution of the Safe Drinking Water Act and the responsibilities of base personnel involved in compliance with the Act. It also describes the monitoring requirements, analytical requirements, best available technology for controlling contaminants, and public notification requirements for regulated contaminants. The appendixes include proposed contaminants and state water quality agencies. Each Air Force public water distribution system (PWDS) must comply with the SDWA, and the National Primary Drinking Water Regulations (NPDWRs). In the United States and its territories, the provisions of themore » SDWA and the NPDWRs are enforced by the states except in the few instances in which the state has not been delegated primary enforcement responsibility (primacy) by the EPA. States that have primacy may establish drinking water regulations, monitoring schedules, and reporting requirements more stringent than, or in addition to, those in the NPDWRs. Air Force public water systems in these states are required to comply with these additional requirements as well as federal enforcement actions as carried out by the EPA Regional Office.« less
Environmental change mediates mate choice for an extended phenotype, but not for mate quality.
Head, Megan L; Fox, Rebecca J; Barber, Iain
2017-01-01
Sexual cues, including extended phenotypes, are expected to be reliable indicators of male genetic quality and/or provide information on parental quality. However, the reliability of these cues may be dependent on stability of the environment, with heterogeneity affecting how selection acts on such traits. Here, we test how environmental change mediates mate choice for multiple sexual traits, including an extended phenotype--the structure of male-built nests - in stickleback fish. First, we manipulated the dissolved oxygen (DO) content of water to create high or low DO environments in which male fish built nests. Then we recorded the mate choice of females encountering these males (and their nests), under either the same or reversed DO conditions. Males in high DO environments built more compact nests than those in low DO conditions and males adjusted their nest structure in response to changing conditions. Female mate choice for extended phenotype (male nests) was environmentally dependent (females chose more compact nests in high DO conditions), while female choice for male phenotype was not (females chose large, vigorous males regardless of DO level). Examining mate choice in this dynamic context suggests that females evaluate the reliability of multiple sexual cues, taking into account environmental heterogeneity. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.
One year water chemistry monitoring of the flooding of the Meirama open pit (NW Spain)
NASA Astrophysics Data System (ADS)
Delgado, J.; Juncosa, R.; Vázquez, A.; Fernández-Bogo, S.
2009-04-01
In December, 2007, after 30 years of operations, the mine of Meirama finished the extraction of brown lignite. Starting in April 2008, the flooding of the open pit has started and this is leading to the formation of a large mining lake (~2 km2 surface and up to 180 m depth) in which surface (river and rain water) and ground waters are involved. Since the beginning of the flooding, lake waters are weekly sampled and analyzed for temperature, pH, redox, EC, TDS, TSS, DO,DIC, DOC, turbidity, alkalinity/acidity as well as nearly 40 inorganic chemical components. Stable water isotopes (deuterium and oxygen) are also being recorded. In order to better understand the dynamic chemical evolution of lake waters, the chemical characteristics of rain water as well as a series of lake tributaries and ground waters are also being measured. Since the beginning of the flooding process, the chemical quality of lake water has experienced an interesting evolution that obeys to a variety of circumstances. The silicic geologic substratum of the catchment determines that both ground and surface waters have a rather low alkalinity. Moreover, the presence of disseminated sulfides (mainly pyrite) within the schistous materials of the mine slopes and internal rock dumps provokes a significant acidic load. From April to October 2008, the lake waters had only the contribution of rain and ground waters. Since the beginning of October, a significant volume of surface waters has been derived to the mine hole. Taking pH as indicator, the first water body had a rather acidic pH (~3) which was progressively amended with the addition of a certain amount of lime to reach an upper value of ~8 by late August. The diminution in the addition of lime up to its elimination, in December, has conducted to the progressive acidification of the lake. At present, an instrumented floating deck is being deployed in the lake. This device will serve as a base point where it is planned to locate a series of instrumentation (complete weather monitoring station, multiparametric probe, sediment trap line) that will complement with depth profiles the surficial sampling performed so far.
Thermal Properties of Lunar Regolith Simulants
NASA Technical Reports Server (NTRS)
Street, Kenneth W., Jr.; Ray, Chandra; Rickman, Doug; Scheiman, Daniel A.
2010-01-01
Various high temperature chemical processes have been developed to extract oxygen and metals from lunar regolith. These processes are tested using terrestrial analogues of the regolith. But all practical terrestrial analogs contain H2O and/or OH-, the presence of which has substantial impact on important system behaviors. We have undertaken studies of lunar regolith simulants to determine the limits of the simulants to validate key components for human survivability during sustained presence on the Moon. Differential Thermal Analysis (DTA) yields information on phase transitions and melting temperatures. Thermo-Gravimetric Analysis (TGA) with Fourier Transform Infrared (FTIR) analysis provides information on evolved gas species and their evolution temperature profiles. The DTA and TGA studies included JSC-1A fine (Johnson Space Center Mare Type 1A simulant), NU-LHT-2M (National Aeronautics and Space Administration (NASA)-- United States Geological Survey (USGS)--Lunar Highlands Type 2M simulant) and its proposed feedstocks: anorthosite; dunite; high quality (HQ) glass and the norite from which HQ glass is produced. As an example, the DTA and TGA profiles for anorthosite follow. The DTA indicates exothermic transitions at 355 and 490 C and endothermic transitions at 970 and 1235 C. Below the 355 C transition, water is lost accounting for approximately 0.1 percent mass loss. Just above 490 C a second type of water is lost, presumably bound in lattices of secondary minerals along with other volatile oxides. Limited TGA-FTIR data is available at the time of this writing. For JSC-1A fine, the TGA-FTIR indicates at least two kinds of water are evolved in the 100 to 500 and the 700 to 900 C ranges. Evolution of carbon dioxide types occurs in the 250 to 545, 545 to 705, and 705 to 985 C ranges. Geologically, the results are consistent with the evolution of "water" in its several forms, CO2 from break down of secondary carbonates and magmatic, dissolved gas and glass recrystallization
López-Roldán, Ramón; Rubalcaba, Alicia; Martin-Alonso, Jordi; González, Susana; Martí, Vicenç; Cortina, Jose Luis
2016-01-01
A methodology has been developed in order to evaluate the potential risk of drinking water for the health of the consumers. The methodology used for the assessment considered systemic and carcinogenic effects caused by oral ingestion of water based on the reference data developed by the World Health Organisation (WHO) and the Risk Assessment Information System (RAIS) for chemical contaminants. The exposure includes a hypothetical dose received by drinking this water according to the analysed contaminants. An assessment of the chemical quality improvement of produced water in the Drinking Water Treatment Plant (DWTP) after integration of membrane technologies was performed. Series of concentration values covering up to 261 chemical parameters over 5 years (2008-2012) of raw and treated water in the Sant Joan Despí DWTP, at the lower part of the Llobregat River basin (NE Spain), were used. After the application of the methodology, the resulting global indexes were located below the thresholds except for carcinogenic risk in the output of DWTP, where the index was slightly above the threshold during 2008 and 2009 before the upgrade of the treatment works including membrane technologies was executed. The annual evolution of global indexes showed a reduction in the global values for all situations: HQ systemic index based on RAIS dropped from 0.64 to 0.42 for surface water and from 0.61 to 0.31 for drinking water; the R carcinogenic index based on RAIS was negligible for input water and varied between 4.2×10(-05) and 7.4×10(-06) for drinking water; the W systemic index based on the WHO data varied between 0.41 and 0.16 for surface water and between 0.61 and 0.31 for drinking water. A specific analysis for the indexes associated with trihalomethanes (THMs) showed the same pattern. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhang, T.; Zeng, W. H.; Wang, S. R.; Ni, Z. K.
2014-04-01
Temporal and spatial changes to the water quality of Dianchi Lake in southwest China were investigated using monthly monitoring data from 2005 to 2012. Dianchi Lake is divided into two parts, Caohai Lake and Waihai Lake, by a man-made dike. Caohai Lake lies at the north of Dianchi Lake, while Waihai Lake is the main water body of Dianchi Lake and accounts for 96.7% of the whole area of the lake. Based on the analysis of total phosphorus (TP), total nitrogen (TN), and chlorophyll a (Chl a) concentrations, it was determined that, in Caohai Lake, the annual concentrations of these variables ranged from 0.19-1.46 mg L-1, 6.11-16.79 mg L-1, 0.06-0.14 mg L-1, respectively. In addition, the annual concentrations of TP, TN and Chl a in Waihai Lake ranged between 0.13 and 0.20 mg L-1, 1.82 and 3.01 mg L-1, and 0.04 and 0.09 mg L-1, respectively. Cluster analysis (CA) classified the 10 monitoring sites into two clusters (cluster A and cluster B) based on similarities of water quality characteristics. Our data revealed that the current status of water quality within Caohai Lake was much worse than that of Waihai Lake. Water quality was seriously degraded during the economic boom near the period of the "Eleventh Five-Year Plan" (2005-2010), and gradually improved from 2010 to 2012 because of the "standard emission directive to industry". The main factors that influenced the spatial and temporal changes to water quality were natural factors including lake evolution and regional characteristic as well as human factors such as pollution load into the lake and management strategies that were already adopted. Some activities and regulations were implemented to enhance the lake environment by controlling wastewater emissions and establishing regulations to protect the lakes in the Yunnan Province. However, problems with institutional fragmentation (horizontal and vertical), simple treatment methods, low-intensity investment in pollution control, and lack of meaningful endogenous pollution control strategies were still present in the lake management strategy. To solve these problems, suitable control measures are needed, especially considering the current old-age status of Dianchi Lake. The fundamental improvement of the water quality within Caohai Lake was dependent on the measures taken in the upper reaches of the Caohai Watershed, including further recovery of submerged plants, resource utilization by floating plants and the reinforcement of sediment disposal. Management strategies for endogenous pollution in Waihai Lake were mainly dependent on restocking algae-eating fish and the ecological restoration of macrophytes. In this way, the swamping trend and the ageing process that is occurring in Dianchi Lake can be stunted. And the management strategies would be a contribution to the management of water conflicts between mankind and ecosystems in similar lakes.
Decision Support Model for Optimal Management of Coastal Gate
NASA Astrophysics Data System (ADS)
Ditthakit, Pakorn; Chittaladakorn, Suwatana
2010-05-01
The coastal areas are intensely settled by human beings owing to their fertility of natural resources. However, at present those areas are facing with water scarcity problems: inadequate water and poor water quality as a result of saltwater intrusion and inappropriate land-use management. To solve these problems, several measures have been exploited. The coastal gate construction is a structural measure widely performed in several countries. This manner requires the plan for suitably operating coastal gates. Coastal gate operation is a complicated task and usually concerns with the management of multiple purposes, which are generally conflicted one another. This paper delineates the methodology and used theories for developing decision support modeling for coastal gate operation scheduling. The developed model was based on coupling simulation and optimization model. The weighting optimization technique based on Differential Evolution (DE) was selected herein for solving multiple objective problems. The hydrodynamic and water quality models were repeatedly invoked during searching the optimal gate operations. In addition, two forecasting models:- Auto Regressive model (AR model) and Harmonic Analysis model (HA model) were applied for forecasting water levels and tide levels, respectively. To demonstrate the applicability of the developed model, it was applied to plan the operations for hypothetical system of Pak Phanang coastal gate system, located in Nakhon Si Thammarat province, southern part of Thailand. It was found that the proposed model could satisfyingly assist decision-makers for operating coastal gates under various environmental, ecological and hydraulic conditions.
Beach science in the Great Lakes
Nevers, Meredith B.; Byappanahalli, Murulee N.; Edge, Thomas A.; Whitman, Richard L.
2014-01-01
Monitoring beach waters for human health has led to an increase and evolution of science in the Great Lakes, which includes microbiology, limnology, hydrology, meteorology, epidemiology, and metagenomics, among others. In recent years, concerns over the accuracy of water quality standards at protecting human health have led to a significant interest in understanding the risk associated with water contact in both freshwater and marine environments. Historically, surface waters have been monitored for fecal indicator bacteria (fecal coliforms, Escherichia coli, enterococci), but shortcomings of the analytical test (lengthy assay) have resulted in a re-focusing of scientific efforts to improve public health protection. Research has led to the discovery of widespread populations of fecal indicator bacteria present in natural habitats such as soils, beach sand, and stranded algae. Microbial source tracking has been used to identify the source of these bacteria and subsequently assess their impact on human health. As a result of many findings, attempts have been made to improve monitoring efficiency and efficacy with the use of empirical predictive models and molecular rapid tests. All along, beach managers have actively incorporated new findings into their monitoring programs. With the abundance of research conducted and information gained over the last 25 years, “Beach Science” has emerged, and the Great Lakes have been a focal point for much of the ground-breaking work. Here, we review the accumulated research on microbiological water quality of Great Lakes beaches and provide a historic context to the collaborative efforts that have advanced this emerging science.
Potential uses of pumped urban groundwater: a case study in Sant Adrià del Besòs (Spain)
NASA Astrophysics Data System (ADS)
Jurado, Anna; Vázquez-Suñé, Enric; Pujades, Estanislao
2017-09-01
Urban groundwater has often been over-exploited for industrial uses. Now, this usage tends to be reduced or the resource abandoned due to pollution and/or changes in land use. The use and the subsequent disuse of groundwater has resulted in rising water tables that damage underground structures (e.g., building basements and underground car parks and tunnels), leading to the need for additional pumping in urban areas. In the case of the underground parking lot of Sant Adrià del Besòs (Barcelona, NE Spain), large amounts of urban groundwater are pumped to avoid seepage problems. Can this pumped groundwater be used for other purposes (e.g., drinking water and urban irrigation) instead of wasting this valuable resource? To answer this question, it was necessary to quantify the groundwater recharge and to assess the evolution of groundwater quality. The limiting factor at this study site is the groundwater quality because ammonium and some metals (iron and manganese) are present at high concentrations. Hence, further treatment would be needed to meet drinking water requirements. The pumped groundwater could also be used for supplementing river flow for ecological benefit and/or for mitigating seawater intrusion problems. Currently, only a small amount of this urban groundwater is used for cleaning public areas and watering public gardens. This situation highlighted the urgent need to manage this resource in a responsible and more efficient manner, especially in moments of high water demand such as drought periods.
Hydrogeochemical quality and suitability studies of groundwater in northern Bangladesh.
Islam, M J; Hakim, M A; Hanafi, M M; Juraimi, Abdul Shukor; Aktar, Sharmin; Siddiqa, Aysha; Rahman, A K M Shajedur; Islam, M Atikul; Halim, M A
2014-07-01
Agriculture, rapid urbanization and geochemical processes have direct or indirect effects on the chemical composition of groundwater and aquifer geochemistry. Hydro-chemical investigations, which are significant for assessment of water quality, were carried out to study the sources of dissolved ions in groundwater of Dinajpur district, northern Bangladesh. The groundwater samplish were analyzed for physico-chemical properties like pH, electrical conductance, hardness, alkalinity, total dissolved solids and Ca2+, Mg2+, Na+, K+, CO3(2-), HCO3(-), SO4(2-) and Cl- ions, respectively. Based on the analyses, certain parameters like sodium adsorption ratio, soluble sodium percentage, potential salinity, residual sodium carbonate, Kelly's ratio, permeability index and Gibbs ratio were also calculated. The results showed that the groundwater of study area was fresh, slightly acidic (pH 5.3-6.4) and low in TDS (35-275 mg I(-1)). Ground water of the study area was found suitable for irrigation, drinking and domestic purposes, since most of the parameters analyzed were within the WHO recommended values for drinking water. High concentration of NO3- and Cl- was reported in areas with extensive agriculture and rapid urbanization. Ion-exchange, weathering, oxidation and dissolution of minerals were major geochemical processes governing the groundwater evolution in study area. Gibb's diagram showed that all the samples fell in the rock dominance field. Based on evaluation, it is clear that groundwater quality of the study area was suitable for both domestic and irrigation purposes.
Water-rock interaction and geochemistry of groundwater from the Ain Azel aquifer, Algeria.
Belkhiri, Lazhar; Mouni, Lotfi; Tiri, Ammar
2012-02-01
Hydrochemical, multivariate statistical, and inverse geochemical modeling techniques were used to investigate the hydrochemical evolution within the Ain Azel aquifer, Algeria. Cluster analysis based on major ion contents defined 3 main chemical water types, reflecting different hydrochemical processes. The first group water, group 1, has low salinity (mean EC = 735 μS/cm). The second group waters are classified as Cl-HCO(3)-alkaline earth type. The third group is made up of water samples, the cation composition of which is dominated by Ca and Mg with anion composition varying from dominantly Cl to dominantly HCO(3) plus SO(4). The varifactors obtained from R-mode FA indicate that the parameters responsible for groundwater quality variations are mainly related to the presence and dissolution of some carbonate, silicate, and evaporite minerals in the aquifer. Inverse geochemical modeling along groundwater flow paths indicates the dominant processes are the consumption of CO(2), the dissolution of dolomite, gypsum, and halite, along with the precipitation of calcite, Ca-montmorillonite, illite, kaolinite, and quartz. © Springer Science+Business Media B.V. 2011
Zanchett, Giliane; Oliveira-Filho, Eduardo C.
2013-01-01
Cyanobacteria or blue-green algae are among the pioneer organisms of planet Earth. They developed an efficient photosynthetic capacity and played a significant role in the evolution of the early atmosphere. Essential for the development and evolution of species, they proliferate easily in aquatic environments, primarily due to human activities. Eutrophic environments are conducive to the appearance of cyanobacterial blooms that not only affect water quality, but also produce highly toxic metabolites. Poisoning and serious chronic effects in humans, such as cancer, have been described. On the other hand, many cyanobacterial genera have been studied for their toxins with anticancer potential in human cell lines, generating promising results for future research toward controlling human adenocarcinomas. This review presents the knowledge that has evolved on the topic of toxins produced by cyanobacteria, ranging from their negative impacts to their benefits. PMID:24152991
Zanchett, Giliane; Oliveira-Filho, Eduardo C
2013-10-23
Cyanobacteria or blue-green algae are among the pioneer organisms of planet Earth. They developed an efficient photosynthetic capacity and played a significant role in the evolution of the early atmosphere. Essential for the development and evolution of species, they proliferate easily in aquatic environments, primarily due to human activities. Eutrophic environments are conducive to the appearance of cyanobacterial blooms that not only affect water quality, but also produce highly toxic metabolites. Poisoning and serious chronic effects in humans, such as cancer, have been described. On the other hand, many cyanobacterial genera have been studied for their toxins with anticancer potential in human cell lines, generating promising results for future research toward controlling human adenocarcinomas. This review presents the knowledge that has evolved on the topic of toxins produced by cyanobacteria, ranging from their negative impacts to their benefits.
Structure and transformation of tactoids in cellulose nanocrystal suspensions
NASA Astrophysics Data System (ADS)
Wang, Pei-Xi; Hamad, Wadood Y.; MacLachlan, Mark J.
2016-05-01
Cellulose nanocrystals obtained from natural sources are of great interest for many applications. In water, cellulose nanocrystals form a liquid crystalline phase whose hierarchical structure is retained in solid films after drying. Although tactoids, one of the most primitive components of liquid crystals, are thought to have a significant role in the evolution of this phase, they have evaded structural study of their internal organization. Here we report the capture of cellulose nanocrystal tactoids in a polymer matrix. This method allows us to visualize, for the first time, the arrangement of cellulose nanocrystals within individual tactoids by electron microscopy. Furthermore, we can follow the structural evolution of the liquid crystalline phase from tactoids to iridescent-layered films. Our insights into the early nucleation events of cellulose nanocrystals give important information about the growth of cholesteric liquid crystalline phases, especially for cellulose nanocrystals, and are crucial for preparing photonics-quality films.
NASA Astrophysics Data System (ADS)
Paillet, Frederick
2012-08-01
A simple mass-balance code allows effective modeling of conventional fluid column resistivity logs in dilution tests involving column replacement with either distilled water or dilute brine. Modeling a series of column profiles where the inflowing formation water introduces water quality interfaces propagating along the borehole gives effective estimates of the rate of borehole flow. Application of the dilution model yields estimates of borehole flow rates that agree with measurements made with the heat-pulse flowmeter under ambient and pumping conditions. Model dilution experiments are used to demonstrate how dilution logging can extend the range of borehole flow measurement at least an order of magnitude beyond that achieved with flowmeters. However, dilution logging has the same dynamic range limitation encountered with flowmeters because it is difficult to detect and characterize flow zones that contribute a small fraction of total flow when that contribution is superimposed on a larger flow. When the smaller contribution is located below the primary zone, ambient downflow may disguise the zone if pumping is not strong enough to reverse the outflow. This situation can be addressed by increased pumping. But this is likely to make the moveout of water quality interfaces too fast to measure in the upper part of the borehole, so that a combination of flowmeter and dilution method may be more appropriate. Numerical experiments show that the expected weak horizontal flow across the borehole at conductive zones would be almost impossible to recognize if any ambient vertical flow is present. In situations where natural water quality differences occur such as flowing boreholes or injection experiments, the simple mass-balance code can be used to quantitatively model the evolution of fluid column logs. Otherwise, dilution experiments can be combined with high-resolution flowmeter profiles to obtain results not attainable using either method alone.
NASA Astrophysics Data System (ADS)
Alazard, M.; Boisson, A.; Maréchal, J.-C.; Perrin, J.; Dewandel, B.; Schwarz, T.; Pettenati, M.; Picot-Colbeaux, G.; Kloppman, W.; Ahmed, S.
2016-02-01
The recharge flow paths in a typical weathered hard-rock aquifer in a semi-arid area of southern India were investigated in relation to structures associated with a managed aquifer recharge (MAR) scheme. Despite the large number of MAR structures, the mechanisms of recharge in their vicinity are still unclear. The study uses a percolation tank as a tool to identify the input signal of the recharge and uses multiple measurements (piezometric time series, electrical conductivity profiles in boreholes) compared against heat-pulse flowmeter measurements and geochemical data (major ions and stable isotopes) to examine recharge flow paths. The recharge process is a combination of diffuse piston flow and preferential flow paths. Direct vertical percolation appears to be very limited, in contradiction to the conceptual model generally admitted where vertical flow through saprolite is considered as the main recharge process. The horizontal component of the flow leads to a strong geochemical stratification of the water column. The complex recharge pattern, presented in a conceptual model, leads to varied impacts on groundwater quality and availability in both time and space, inducing strong implications for water management, water quality evolution, MAR monitoring and longer-term socio-economic costs.
Soil quality evolution after land use change from paddy soil to vegetable land.
Cao, Z H; Huang, J F; Zhang, C S; Li, A F
2004-01-01
A survey was done in 15 typical villages, 150 soil and 86 vegetable plant samples were taken in Jiaxin prefecture of the Taihu Lake region, northern Zhejian province. Results indicate that after 15-20 years land use changed from the paddy rice-wheat (or oilseed rape) double cropping system, to a continuous vegetable land has caused soil quality dramatic change. (1) Acidification: average soil pH was 5.4; about 61% of total samples were pH < 5.5. It was 0.9 units lower than 10 years ago with same upland vegetable cultivation and was 1.2 units lower than soil pH of paddy rice-wheat (or oilseed rape) rotation. (2) Fertilizer salt accumulation: the average salt content was 0.28%, among these about 36.2% of the total samples contained more than 0.3%. (3) Nitrate N and available phosphorus (P) over accumulation: on average it was 279 mg NO3-N/kg, and 45-115 mg P/kg. Nitrate N four times higher and available P 4-10 times more than it is in present paddy rice-wheat rotation soils respectively. This has caused wide concern because of possible groundwater and well drinking water pollution by leached nitrate N and the P losses to water by runoff from vegetable lands induce surface water eutrophication.
NASA Astrophysics Data System (ADS)
Behroozmand, A. A.; Teatini, P.; Pedersen, J. B. B.; Auken, E.; Tosatto, O.; Christiansen, A. V.
2015-12-01
During the last century, many large irrigation projects have been initiated in arid lands worldwide. Despite a tremendous increase in food production, a common problem when characterizing these zones is land degradation in form of waterlogging. As results, large volumes of water are lost due to surplus irrigation in regions where water availability is extremely challenging for both population survival and economic development. The Nubariya depression, Western Desert (Egypt), is a clear example of this mechanism. Following the reclamation of desert lands for agricultural production, an artificial brackish and contaminated lake developed in the area in the late 1990s and presently extends for about 2.5 km2. Available data provide evidence of a simultaneous general deterioration of the groundwater system. With the main objectives of understanding the hydrological evolution of the area, characterizing the hydrogeological setting and developing scenarios for artificial aquifer remediation and recharge, an extensive hydrogeophysical investigation was carried out in this challenging environment using Magnetic Resonance Sounding (MRS, also called surface NMR) and ground-based Transient EM (TEM). The integrated interpretation of the geophysical surveys, properly calibrated with a number of boreholes, provides a clear hydrogeological picture of the upper 100 m sedimentary structure, in terms of both lithology and groundwater quality. The information is then used to set up a regional groundwater flow and a local density-dependent flow and transport numerical model to reproduce the past evolution of the aquifer system and develop a few scenarios for artificial aquifer recharge using the treated waters provided by a nearby waste-water treatment plant. The research outcomes point the hydrological challenges that emerge for an effective management of water resources in reclaimed desert areas and highlight the effectiveness of integrating advanced geophysical and modeling methodologies.
Ejaculate quality and constraints in relation to sperm competition levels among eutherian mammals.
Lüpold, Stefan
2013-10-01
The outcome of sperm competition is influenced by the relative quantity and quality of sperm among competing ejaculates. Whereas it is well established that individual ejaculate traits evolve rapidly under postcopulatory sexual selection, little is known about other factors that might influence the evolution of ejaculates. For example, the metabolic rate is likely to affect the sperm production rate and the cellular activity or metabolism of sperm, and it has recently been suggested to constrain the evolution of sperm length in large but not small mammals. I thus examined in eutherian mammals how ejaculate quality traits vary with one another and with testis mass, body size, and metabolism. I found all ejaculate traits to covary positively with one another and to increase with relative testis mass. When controlling for testis mass, small-bodied species showed superior sperm quality (but not sperm number). Furthermore, sperm motility and viability were positively associated with the mass-corrected metabolic rate, but the percentage of morphologically normal and acrosome-intact sperm were not. These results indicate that body size and the energy budget may also influence the evolution of ejaculate quality, although these influences appear to vary among traits. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.
NASA Astrophysics Data System (ADS)
Aldea, Alexandru; Aldea, Mihaela
2016-08-01
The growth and concentration of population, housing and industry in urban and suburban areas in the continuous evolution of a city over time causes complex social, economic, and physical challenges. The population and its relationship with the use and development of the land and water is a critical issue of urban growth, and since ancient times land, water and man were directly involved in the human populations' survival. Nevertheless the current potential of study over this relationship between urban growth, water supply, drainage and water resources conditions becomes more and more attractive due to the possibility to make use of the broader variety of information sources and technologies readily available in recent years, with emphasis on the open data and on the big data as primary sources. In this regard we present some new possibilities of analyses over the demographics, land use/land cover and water supply and conservation based on a study over a Romanian region of development (Bucharest-Ilfov). As urban development usually outgrows the existing water supply systems, the resolution consists in drilling new and deeper wells, building new water distribution pipelines, building longer aqueducts and larger reservoirs, or finding new sources and constructing completely new water supply systems, water supplies may evolve this way from a result into a cause and driver of urban growth. The evolution trends of the studied area was estimated based on the open satellite time-series imagery and remote sensing techniques by land use/land cover extraction and the identification of the changes in urbanization. The survey is mainly focused on the expansion of the water network in terms of areal, total length and number of connections correlated with the amount of water produced, consumed and lost within a supply zone. Some urban human activities including the industrial ones alter water resource by pollution, over pumping of groundwater, construction of dams and reservoirs. In areas of rapid growth the worse problems came from the inadequate amount of potable water, the continuous deterioration of water quality and the slow progress in the water resources management and supply. The effects of urban dynamics over the water use and sustainability deserves an increasing study over the recent history in order to provide for an optimal management of the interrelationships between them.
Evolution of water recycling in Australian cities since 2003.
Radcliffe, J C
2010-01-01
The prolonged Australian drought which commenced in 2002, and the agreement between Australia's Commonwealth and States/Territories governments to progress water reform through the National Water Initiative, has resulted in many new recycling projects in Australia's capital cities. Dual reticulation systems are being advanced in new subdivision developments in Sydney, Melbourne and Adelaide. Brisbane has installed three large Advanced Water Treatment Plants that are designed to send indirect potable recycled water to the Wivenhoe Dam which is Brisbane's principal water reservoir. Numerous water recycling projects are serving industry and agriculture. Experimental managed aquifer recharge is being undertaken with wetland-treated stormwater in Adelaide and reverse osmosis treated wastewater in Perth. New National Water Quality Management Strategy recycled water guidelines have been developed for managing environmental risks, for augmentation of drinking water supplies, for managed aquifer recharge and for stormwater harvesting and reuse. Many recent investments are part-supported through Commonwealth government grants. Desalination plants are being established in Melbourne and Adelaide and a second one in Perth in addition to the newly-operational plants in Perth, South-East Queensland and Sydney. Despite there being numerous examples of unplanned indirect potable recycling, most governments remain reluctant about moving towards planned potable recycling. There is evidence of some policy bans still being maintained by governments but the National Water Commission continues to reinforce the necessity of an even-handed objective consideration of all water supply options.
NASA Astrophysics Data System (ADS)
Neumann, K.; Dowling, C. B.; Moraru, C.; Hannigan, R. E.
2008-12-01
The Mississippi Embayment, located in the southeastern U.S., is a syncline formed by the northward excursion of the Gulf of Coastal Plain. Structurally, the Mississippi Embayment is a hydrogeological basin consisting of six regional aquifers. These productive aquifers yield good-quality waters. The Mississippi Embayment Regional Ground Water Study group located at Arkansas State University compiled and organized the available water chemistry and groundwater level data from the USGS groundwater monitoring database. The uppermost unconfined horizon forms the Mississippi River Valley Alluvial Aquifer (ALVM), one of the largest unconfined aquifers in the world. The Holocene and Pleistocene ALVM is formed from sand, gravel, and loess. The majority of the groundwater wells (approximately 80%) are drilled in the ALVM. As the groundwater levels have fallen in the unconfined ALVM, more groundwater wells are drilled in the deeper aquifers-the Upper, Middle, and Lower Claiborne Aquifers. The Ecocene Upper Claiborne Aquifer protolith is sand, silt, and clay while the Eocene Middle Claiborne and Lower Claiborne aquifers are sand and minor clay. We focused our investigation of the spatial and temporal evolution of groundwater in the Arkansas section of the Mississippi Embayment by using wells with long term monitoring records (1928 - 2005). Overall, the groundwater levels of the unconfined aquifer (ALVM) have decreased; we have not yet evaluated the lower aquifer water level changes. Attention was paid to rock-water interactions along flowpaths in the ALVM and Upper Claiborne aquifers, and to temporal changes at specific sampling sites. The study is utilizing groundwater pH, cation, anion, and nutrient data in the programs AquaChem and PHREEQE to describe mineral and CO2 saturations in groundwater. First results indicate that the modeling allows the identification of different processes (CO2 pressure, calcite saturation) that control distinct geochemical provinces, e.g. urban regions and regions dominated by river water recharge.
NASA Astrophysics Data System (ADS)
Nganje, T. N.; Hursthouse, A. S.; Edet, Aniekan; Stirling, D.; Adamu, C. I.
2017-05-01
Water chemistry in the shale bedrock of the Cretaceous-Tertiary of the Cross River and Niger Delta hydrological basins has been investigated using major ions. To carry out a characterization of the water bearing units, 30 and 16 representatives surface and groundwater samples were collected. The evolution of the water is characterized by enhanced content of sodium, calcium and sulphate as a result of leaching of shale rock. The spatial changes in groundwater quality of the area shows an anomalous concentrations of ions in the central parts, while lower values characterize the eastern part of the basin covering Ogoja, Ikom and Odukpani areas. The values of total dissolved solids (TDS) and ions increases down gradient in the direction of groundwater flow. The dissolution of halite and gypsum explains part of the contained Na+, Ca2+, Cl- and SO4 2-, but other processes such as ion exchange, silicate weathering and pyrite oxidation also contribute to water composition. The assessment with contamination indicators such as TDS, hardness, chloride, nitrate and sulphate indicates that the water in area is suitable for human consumption in some locations. Modelling using MINTEQA2 program shows that the water from all the shale water bearing units are under saturated with respect to gypsum.
46 CFR 148.11 - Hazardous or potentially dangerous characteristics.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Contact with water may cause evolution of flammable gases, which may form explosive mixtures with air. 3 Contact with water may cause evolution of toxic gases. 4 If involved in a fire, will greatly intensify the...
46 CFR 148.11 - Hazardous or potentially dangerous characteristics.
Code of Federal Regulations, 2013 CFR
2013-10-01
... Contact with water may cause evolution of flammable gases, which may form explosive mixtures with air. 3 Contact with water may cause evolution of toxic gases. 4 If involved in a fire, will greatly intensify the...
46 CFR 148.11 - Hazardous or potentially dangerous characteristics.
Code of Federal Regulations, 2011 CFR
2011-10-01
... Contact with water may cause evolution of flammable gases, which may form explosive mixtures with air. 3 Contact with water may cause evolution of toxic gases. 4 If involved in a fire, will greatly intensify the...
46 CFR 148.11 - Hazardous or potentially dangerous characteristics.
Code of Federal Regulations, 2014 CFR
2014-10-01
... Contact with water may cause evolution of flammable gases, which may form explosive mixtures with air. 3 Contact with water may cause evolution of toxic gases. 4 If involved in a fire, will greatly intensify the...
Langland, Michael J.; Cinotto, Peter J.; Chichester, Douglas C.; Bilger, Michael D.; Brightbill, Robin A.
2010-01-01
Base-line and long-term monitoring of water resources of the National Guard Training Center at Fort Indiantown Gap in south-central Pennsylvania began in 2002. Results of continuous monitoring of streamflow and turbidity and monthly and stormflow water-quality samples from two continuous-record long-term stream sites, periodic collection of water-quality samples from five miscellaneous stream sites, and annual collection of biological data from 2002 to 2005 at 27 sites are discussed. In addition, results from a stream-geomorphic analysis and classification and a regional groundwater-flow model are included. Streamflow at the facility was above normal for the 2003 through 2005 water years and extremely high-flow events occurred in 2003 and in 2004. Water-quality samples were analyzed for nutrients, sediments, metals, major ions, pesticides, volatile and semi-volatile organic compounds, and explosives. Results indicated no exceedances for any constituent (except iron) above the primary and secondary drinking-water standards or health-advisory levels set by the U.S. Environmental Protection Agency. Iron concentrations were naturally elevated in the groundwater within the watershed because of bedrock lithology. The majority of the constituents were at or below the method detection limit. Sediment loads were dominated by precipitation due to the remnants of Hurricane Ivan in September 2004. More than 60 percent of the sediment load measured during the entire study was transported past the streamgage in just 2 days during that event. Habitat and aquatic-invertebrate data were collected in the summers of 2002-05, and fish data were collected in 2004. Although 2002 was a drought year, 2003-05 were above-normal flow years. Results indicated a wide diversity in invertebrates, good numbers of taxa (distinct organisms), and on the basis of a combination of metrics, the majority of the 27 sites indicated no or slight impairment. Fish-metric data from 25 sites indicated results similar to the invertebrate data. Stream classification based on evolution of the stream channels indicates about 94 percent of the channels were considered to be in equilibrium (type B or C channels), neither aggrading nor eroding. A regional, uncalibrated groundwater-flow model indicated the surface-water and groundwater-flow divides coincided. Because of folding of rock layers, groundwater was under confined conditions and nearly all the water leaves the facility via the streams.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riback, Joshua A.; Bowman, Micayla A.; Zmyslowski, Adam M.
A substantial fraction of the proteome is intrinsically disordered, and even well-folded proteins adopt non-native geometries during synthesis, folding, transport, and turnover. Characterization of intrinsically disordered proteins (IDPs) is challenging, in part because of a lack of accurate physical models and the difficulty of interpreting experimental results. We have developed a general method to extract the dimensions and solvent quality (self-interactions) of IDPs from a single small-angle x-ray scattering measurement. We applied this procedure to a variety of IDPs and found that even IDPs with low net charge and high hydrophobicity remain highly expanded in water, contrary to the generalmore » expectation that protein-like sequences collapse in water. Our results suggest that the unfolded state of most foldable sequences is expanded; we conjecture that this property was selected by evolution to minimize misfolding and aggregation.« less
Liquid-Assisted Femtosecond Laser Precision-Machining of Silica.
Cao, Xiao-Wen; Chen, Qi-Dai; Fan, Hua; Zhang, Lei; Juodkazis, Saulius; Sun, Hong-Bo
2018-04-28
We report a systematical study on the liquid assisted femtosecond laser machining of quartz plate in water and under different etching solutions. The ablation features in liquid showed a better structuring quality and improved resolution with 1/3~1/2 smaller features as compared with those made in air. It has been demonstrated that laser induced periodic structures are present to a lesser extent when laser processed in water solutions. The redistribution of oxygen revealed a strong surface modification, which is related to the etching selectivity of laser irradiated regions. Laser ablation in KOH and HF solution showed very different morphology, which relates to the evolution of laser induced plasma on the formation of micro/nano-features in liquid. This work extends laser precision fabrication of hard materials. The mechanism of strong absorption in the regions with permittivity (epsilon) near zero is discussed.
Technologies for ECLSS Evolution
NASA Technical Reports Server (NTRS)
Diamant, Bryce L.
1990-01-01
Viewgraphs and discussion on technologies for Environmental Control and Life Support System (ECLSS) evolution are presented. Topics covered include: atmosphere revitalization including CO2 removal, CO2 reduction, O2 generation, and trace contaminant control; water recovery and management including urine processing, hygiene water processing, and potable water processing; and waste management. ECLSS technology schematics, process diagrams, and fluid interfaces are included.
NASA Astrophysics Data System (ADS)
Goffin, Angélique; Guérin, Sabrina; Rocher, Vincent; Varrault, Gilles
2016-04-01
Dissolved organic matter (DOM) influences wastewater treatment plants efficiency (WTTP): variations in its quality and quantity can induce a foaming phenomenon and a fouling event inside biofiltration processes. Moreover, in order to manage denitrification step (control and optimization of the nitrate recirculation), it is important to be able to estimate biodegradable organic matter quantity before biological treatment. But the current methods used to characterize organic matter quality, like biological oxygen demand are laborious, time consuming and sometimes not applicable to directly monitor organic matter in situ. In the context of MOCOPEE research program (www.mocopee.com), this study aims to assess the use of optical techniques, such as UV-Visible absorbance and more specifically fluorescence spectroscopy in order to monitor and to optimize process efficiency in WWTP. Fluorescence excitation-emission matrix (EEM) spectroscopy was employed to prospect the possibility of using this technology online and in real time to characterize dissolved organic matter in different effluents of the WWTP Seine Centre (240,000 m3/day) in Paris, France. 35 sewage water influent samples were collected on 10 days at different hours. Data treatment were performed by two methods: peak picking and parallel factor analysis (PARAFAC). An evolution of DOM quality (position of excitation - emission peaks) and quantity (intensity of fluorescence) was observed between the different treatment steps (influent, primary treatment, biological treatment, effluent). Correlations were found between fluorescence indicators and different water quality key parameters in the sewage influents. We developed different multivariate linear regression models in order to predict a variety of water quality parameters by fluorescence intensity at specific excitation-emission wavelengths. For example dissolved biological oxygen demand (r2=0,900; p<0,0001) and ammonium concentration (r2=0,898; p<0,0001) present good correlation with specific fluorescence peaks and indicators. These indicators derived from 3D spectrofluorescence could be used in order to characterize DOM online and thus to optimize process efficiency in WWTP.
The French network of hydrogeological sites H+
NASA Astrophysics Data System (ADS)
Davy, P.; Le Borgne, T.; Bour, O.; Gautier, S.; Porel, G.; Bodin, J.; de Dreuzy, J.; Pezard, P.
2008-12-01
For groundwater issues (potential leakages in waste repository, aquifer management "), the development of modeling techniques is far ahead of the actual knowledge of aquifers. This raises two fundamental issues: 1) which and how much data are necessary to make predictions accurate enough for aquifer management issues; 2) which models remain relevant to describe the heterogeneity and complexity of geological systems. The French observatory H+ was created in 2002 with the twofold motivation of acquiring a large database for validating models of heterogeneous aquifers, and of surveying groundwater quality evolution in the context of environmental changes. H+ is a network of 4 sites (Ploemeur, Brittany, France; HES Poitiers, France; Cadarache, France; Campos, Mallorca, Spain) with different geological, climatic, and economic contexts. All of them are characterized by a highly heterogeneous structure (fractured crystalline basement for Ploemeur, karstified and fractured limestone for Poitiers, Cadarache and Mallorca), which is far to be taken into account by basic models. Ploemeur is exploited as a tap-water plant for a medium-size coastal city (15,000 inhabitants) for 20 years. Each site is developed for long term investigation and monitoring. They involves a dense network of boreholes, detailed geological and geophysical surveys, periodic campaigns and/or permanent measurements of groundwater flow, water chemistry, geophysical signals (including ground motions), climatic parameter, etc. Several large-scale flow experiments are scheduled per year to investigate the aquifer structure with combined geophysical, hydrogeological, and geochemical instruments. All this information is recorded in a database that has been developed to improve the sustainability and quality of data, and to be used as a collaborative tool for both site researchers and modelers. This project lasts now for 5 years. It is a short time to collect the amount of information necessary to apprehend the complexity of aquifers; but it is already enough to obtain a few important scientific results about the very nature of the flow heterogeneity, the origin and residence time of water elements, the kinetic of geochemical processes, etc. We have also developed new methods to investigate aquifers (in-situ flow measurements, flow experiment designs, groundwater dating, versatile in-situ probes, etc.). This experience aiming at building up long term knowledge appears extremely useful to address critical issues related to groundwater aquifers: the structure and occurrence of productive aquifer in crystalline basement, the assessment of aquifer protection area in the context of highly heterogeneous flow, the biochemical reactivity processes, the long term evolution of both water quantity and quality in the context of significant environmental changes, for instance.
Chen, Qian-Qian; Hou, Chun-Chao; Wang, Chuan-Jun; Yang, Xiao; Shi, Rui; Chen, Yong
2018-06-06
NiFe-layered double hydroxide (NiFe LDH) is a state-of-the-art oxygen evolution reaction (OER) electrocatalyst, yet it suffers from rather poor catalytic activity for the hydrogen evolution reaction (HER) due to its extremely sluggish water dissociation kinetics, severely restricting its application in overall water splitting. Herein, we report a novel strategy to expedite the HER kinetics of NiFe LDH by an Ir4+-doping strategy to accelerate the water dissociation process (Volmer step), and thus this catalyst exhibits superior and robust catalytic activity for finally oriented overall water splitting in 1 M KOH requiring only a low initial voltage of 1.41 V delivering at 20 mA cm-2 for more than 50 h.
Quality-Assurance Plan for Water-Quality Activities in the USGS Ohio Water Science Center
Francy, Donna S.; Shaffer, Kimberly H.
2008-01-01
In accordance with guidelines set forth by the Office of Water Quality in the Water Resources Discipline of the U.S. Geological Survey, a quality-assurance plan has been written for use by the Ohio Water Science Center in conducting water-quality activities. This quality-assurance plan documents the standards, policies, and procedures used by the Ohio Water Science Center for activities related to the collection, processing, storage, analysis, and publication of water-quality data. The policies and procedures documented in this quality-assurance plan for water-quality activities are meant to complement the Ohio Water Science Center quality-assurance plans for water-quality monitors, the microbiology laboratory, and surface-water and ground-water activities.
Recent advances in cellulose and chitosan based membranes for water purification: A concise review.
Thakur, Vijay Kumar; Voicu, Stefan Ioan
2016-08-01
Recently membrane technology has emerged as a new promising and pervasive technology due to its innate advantages over traditional technologies such as adsorption, distillation and extraction. In this article, some of the recent advances in developing polymeric composite membrane materials for water purification from natural polysaccharide based polymers namely cellulose derivatives and chitosan are concisely reviewed. The impact of human social, demographic and industrial evolution along with expansion through environment has significantly affected the quality of water by pollution with large quantities of pesticides, minerals, drugs or other residues. At the forefront of decontamination and purification techniques, we found the membrane materials from polymers as a potential alternative. In an attempt to reduce the number of technical polymers widely used in the preparation of membranes, many researchers have reported new solutions for desalination or retention of organic yeasts, based on bio renewable polymers like cellulose derivatives and chitosan. These realizations are presented and discussed in terms of the most important parameters of membrane separation especially water flux and retention in this article. Published by Elsevier Ltd.
Applicability of biotechnologically produced insect silks.
Herold, Heike M; Scheibel, Thomas
2017-09-26
Silks are structural proteins produced by arthropods. Besides the well-known cocoon silk, which is produced by larvae of the silk moth Bombyx mori to undergo metamorphosis inside their silken shelter (and which is also used for textile production by men since millennia), numerous further less known silk-producing animals exist. The ability to produce silk evolved multiple independent times during evolution, and the fact that silk was subject to convergent evolution gave rise to an abundant natural diversity of silk proteins. Silks are used in air, under water, or like honey bee silk in the hydrophobic, waxen environment of the bee hive. The good mechanical properties of insect silk fibres together with their non-toxic, biocompatible, and biodegradable nature renders these materials appealing for both technical and biomedical applications. Although nature provides a great diversity of material properties, the variation in quality inherent in materials from natural sources together with low availability (except from silkworm silk) impeded the development of applications of silks. To overcome these two drawbacks, in recent years, recombinant silks gained more and more interest, as the biotechnological production of silk proteins allows for a scalable production at constant quality. This review summarises recent developments in recombinant silk production as well as technical procedures to process recombinant silk proteins into fibres, films, and hydrogels.
Su, Min; Boots, Mike
2017-03-07
Understanding the drivers of parasite evolution and in particular disease virulence remains a major focus of evolutionary theory. Here, we examine the role of resource quality and in particular spatial environmental heterogeneity in the distribution of these resources on the evolution of virulence. There may be direct effects of resources on host susceptibility and pathogenicity alongside effects on reproduction that indirectly impact host-parasite population dynamics. Therefore, we assume that high resource quality may lead to both increased host reproduction and/or increased disease resistance. In completely mixed populations there is no effect of resource quality on the outcome of disease evolution. However, when there are local interactions higher resource quality generally selects for higher virulence/transmission for both linear and saturating transmission-virulence trade-off assumptions. The exception is that in castrators (i.e., infected hosts have no reproduction), higher virulence is selected for both low and high resource qualities at mixed local and global infection. Heterogeneity in the distribution of environment resources only has an effect on the outcome in castrators where random distributions generally select for higher virulence. Overall, our results further underline the importance of considering spatial structure in order to understand evolutionary processes. Copyright © 2016 Elsevier Ltd. All rights reserved.
Geochemical Processes During Managed Aquifer Recharge With Desalinated Seawater
NASA Astrophysics Data System (ADS)
Ganot, Y.; Holtzman, R.; Weisbrod, N.; Russak, A.; Katz, Y.; Kurtzman, D.
2018-02-01
We study geochemical processes along the variably-saturated zone during managed aquifer recharge (MAR) with reverse-osmosis desalinated seawater (DSW). The DSW, post-treated at the desalination plant by calcite dissolution (remineralization) to meet the Israeli water quality standards, is recharged into the Israeli Coastal Aquifer through an infiltration pond. Water quality monitoring during two MAR events using suction cups and wells inside the pond indicates that cation exchange is the dominant subsurface reaction, driven by the high Ca2+ concentration in the post-treated DSW. Stable isotope analysis shows that the shallow groundwater composition is similar to the recharged DSW, except for enrichment of Mg2+, Na+, Ca2+, and HCO3-. A calibrated variably-saturated reactive transport model is used to predict the geochemical evolution during 50 years of MAR for two water quality scenarios: (i) post-treated DSW (current practice) and (ii) soft DSW (lacking the remineralization post-treatment process). The latter scenario was aimed to test soil-aquifer-treatment (SAT) as an alternative post-treatment technique. Both scenarios provide an enrichment of ˜2.5 mg L-1 in Mg2+ due to cation exchange, compared to practically zero Mg2+ currently found in the Israeli DSW. Simulations of the alternative SAT scenario provide Ca2+ and HCO3- remineralization due to calcite dissolution at levels that meet the Israeli standard for DSW. The simulated calcite content reduction in the sediments below the infiltration pond after 50 years of MAR was low (<1%). Our findings suggest that remineralization using SAT for DSW is a potentially sustainable practice at MAR sites overlying calcareous sandy aquifers.
The evolution of hydrological and water quality conditions on Techirghiol Lake
NASA Astrophysics Data System (ADS)
Maftei, Carmen; Buta, Constantin; Tofan, Lucica
2015-04-01
Changes in climate and environment conditions alter the hydraulic and chemical properties of lakes. With a surface from 1300ha, the Techirghiol Lake, situated on the littoral of the Black Sea at 15km from Constanta town, is considered the greatest hypersaline lake of Romania very well known (from 1891) especially for the curative qualities of its water and mud. Physical and geographical conditions associated with an arid climate regime - where the annual precipitation is less than 400mm and the average temperatures exceed (lead evaporative potential to 700-1000mm), cause a strong concentration of mineral salts that give the lake an excessive salinity. In conditions of excessive salinity forms a therapeutic mud as a result of bacterial decomposition of aquatic organisms that have done there, especially crustaceans Arthemia and algae that live in water. This mud, highly hydrated, rich in minerals, has therapeutic properties, for this reason in Techirghiol has developed a strong health resort. Fresh water is a threat to the therapeutic lake properties. In hydrological year 1961-1962, the overland flow value to the lake was approximately 0.4 million m3, and from 1972-1973 the value reached 6 million cubic meters per year a great contribution was from the irrigation water. One of the consequences is the increasing of the lake level and the second is the decreasing of salinity. For this reason a hydraulic work system has been built to separate the saline water of the lake and the freshwater. The aim of this paper is to investigate the hydrologic and chemical responses of the Techirghiol Lake to the changes in climate and environment conditions.
NASA Astrophysics Data System (ADS)
Mayer, Adriano; Nguyen, Bach Thao; Banton, Olivier
2016-11-01
Radon has been used to determine groundwater velocity and groundwater discharge into wetlands at the southern downstream boundary of the Crau aquifer, southeastern France. This aquifer constitutes an important high-quality freshwater resource exploited for agriculture, industry and human consumption. An increase in salinity occurs close to the sea, highlighting the need to investigate the water balance and groundwater behavior. Darcy velocity was estimated using radon activities in well waters according to the Hamada "single-well method" (involving comparison with radon in groundwater in the aquifer itself). Measurements done at three depths (7, 15 and 21 m) provided velocity ranging from a few mm/day to more than 20 cm/day, with highest velocities observed at the 15-m depth. Resulting hydraulic conductivities agree with the known geology. Waters showing high radon activity and high salinity were found near the presumed shoreline at 3,000 years BP, highlighting the presence of ancient saltwater. Radon activity has also been measured in canals, rivers and ponds, to trace groundwater discharges and evaluate water balance. A model of the radon spatial evolution explains the observed radon activities. Groundwater discharge to surface water is low in pond waters (4 % of total inputs) but significant in canals (55 l/m2/day).
The evolution of costly mate choice against segregation distorters.
Manser, Andri; Lindholm, Anna K; Weissing, Franz J
2017-12-01
The evolution of female preference for male genetic quality remains a controversial topic in sexual selection research. One well-known problem, known as the lek paradox, lies in understanding how variation in genetic quality is maintained in spite of natural selection and sexual selection against low-quality alleles. Here, we theoretically investigate a scenario where females pay a direct fitness cost to avoid males carrying an autosomal segregation distorter. We show that preference evolution is greatly facilitated under such circumstances. Because the distorter is transmitted in a non-Mendelian fashion, it can be maintained in the population despite directional sexual selection. The preference helps females avoid fitness costs associated with the distorter. Interestingly, we find that preference evolution is limited if the choice allele induces a very strong preference or if distortion is very strong. Moreover, the preference can only persist in the presence of a signal that reliably indicates a male's distorter genotype. Hence, even in a system where the lek paradox does not play a major role, costly preferences can only spread under specific circumstances. We discuss the importance of distorter systems for the evolution of costly female choice and potential implications for the use of artificial distorters in pest control. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.
NASA Astrophysics Data System (ADS)
Cary, L.; Kloppmann, W.; Battilani, A.; Bertaki, M.; Blagojevic, S.; Chartzoulakis, K.; Dalsgaard, A.; Forslund, A.; Jovanovic, Z.; Kasapakis, I.
2009-04-01
The safe use of treated domestic wastewater for irrigation needs to address the risks for humans (workers, exposed via contact with irrigation water, soil, crops and food, consumers, exposed via ingestion of fresh and processed food), for animals (via ingestion of crops an soil), for the crops and agricultural productivity (via salinity and trace element uptake), for soil (via accumulation or release of pollutants) as well as for surface, groundwaters and the associated ecosystems (via runoff and infiltration, Kass et al., 2005, Bouwer, 2000). A work package in the EU FP5 project SAFIR is dedicated to study the impact of wastewater irrigation on the soil-water-plant-product system. Its monitoring program comprises pathogens and inorganic pollutants, including both geogenic and potentially anthropogenic trace elements in the aim to better understand soil-irrigation water interactions. The SAFIR field study sites are found in China, Italy, Crete, and Serbia. A performance evaluation of SAFIR-specific treatment technology through the monitoring of waste water and irrigation water quality was made through waste water chemical and microbiological qualities, which were investigated upstream and downstream of the SAFIR specific treatment three times per season. Irrigation water transits through the uppermost soil decimetres to the crop roots. The latter will become, in the course of the irrigation season, the major sink of percolating water, together with evaporation. The water saving irrigation techniques used in SAFIR are surface and subsurface drip irrigation. The investigation of the solid soil phase concentrates on the root zone as main transit and storage compartment for pollutants and, eventually, pathogens. The initial soil quality was assessed through a sampling campaign before the onset of the first year irrigation; the soil quality has been monitored throughout three years under cultivation of tomatoes or potatoes. The plot layout for each of the study sites allows comparing different combinations of (1) water quality, including tap water as a reference, (2) irrigation techniques, and (3) irrigation strategies (including full irrigation, partial root drying, RDI). The replication of each of the combinations on three different plots takes into account the local variations of soil properties and allows a proper statistical treatment. Reactions of the infiltrating water with the soil solid phase are important for the solute cycling, temporary fixation and remobilisation of trace pollutants. The type of reaction (sorption, co-precipitation…) and the reactive mineral phases will also determine the availability of trace elements for the plant and determine the passage towards crops and products. Therefore it is important to assess the soil water quality, directly or indirectly. Direct measurements of soil water imply soil water sampling through an appropriate system; porous cups were installed on the Cretan, Italian and Chinese sites. Indirect evaluation of water-soil interactions can be obtained through sequential extractions. The combination of a variable input function (through diffuse pollution, irrigation, fertigation) and of variable MTE mobility in soils can be expected to lead to short term variations in soil metal concentrations even if such short term variations have been rarely investigated (Féder, 2001; Cary and Trolard, 2008). The sampling focused upon the fully irrigated plots given that the potential impact of irrigation water quality on soil and plant quality can be expected higher for fully irrigated soils compared to other irrigation strategies. Samples were taken within the soil volume of potential influence around each of the drip emitters. This volume varies depending on the nature of the soil and the irrigation system so that each site adopted a specific protocol. For all experiments, three sampling campaigns were scheduled for each irrigation season: at pre-planting, at the end of irrigation, at harvest. The geochemical evolution of soil properties over the 3 years shows significant variations in major and minor elements, especially trace metallic elements. It implies the role of the cultivated plant as a sink of elements which leads to direct loss of elements in the soil system. Bouwer, H., 2000. Groundwater problems caused by irrigation with sewage effluent. Journal of Environmental Health 63, 17-20. Cary L., Trolard F. (2008). Metal mobility in the ground water of a paddy field in Camargue (South eastern France). Journal of Geochemical Exploration 96/2-3 : 132-143. Féder, 2001. Dynamique des processus d'oxydo-reduction dans les sols hydromorphes, These de l'Universite Aix Marseille III. Kass, A. Gavrieli, I. Yechieli, Y. Vengosh A.and Starinsky, A., 2005. The impact of freshwater and wastewater irrigation on the chemistry of shallow groundwater: a case study from the Israeli Coastal Aquifer, Journal of Hydrology, 300, 314-331.
Nabizadeh, Ramin; Valadi Amin, Maryam; Alimohammadi, Mahmood; Naddafi, Kazem; Mahvi, Amir Hossein; Yousefzadeh, Samira
2013-04-26
Developing a water quality index which is used to convert the water quality dataset into a single number is the most important task of most water quality monitoring programmes. As the water quality index setup is based on different local obstacles, it is not feasible to introduce a definite water quality index to reveal the water quality level. In this study, an innovative software application, the Iranian Water Quality Index Software (IWQIS), is presented in order to facilitate calculation of a water quality index based on dynamic weight factors, which will help users to compute the water quality index in cases where some parameters are missing from the datasets. A dataset containing 735 water samples of drinking water quality in different parts of the country was used to show the performance of this software using different criteria parameters. The software proved to be an efficient tool to facilitate the setup of water quality indices based on flexible use of variables and water quality databases.
Biogeochemical control points in a water-limited critical zone
NASA Astrophysics Data System (ADS)
Chorover, J.; Brooks, P. D.; Gallery, R. E.; McIntosh, J. C.; Olshansky, Y.; Rasmussen, C.
2017-12-01
The routing of water and carbon through complex terrain is postulated to control structure evolution in the sub-humid critical zone of the southwestern US. By combining measurements of land-atmosphere exchange, ecohydrologic partitioning, and subsurface biogeochemistry, we seek to quantify how a heterogeneous (in time and space) distribution of "reactants" impacts both short-term (sub-)catchment response (e.g., pore and surface water chemical dynamics) and long-term landscape evolution (e.g., soil geochemistry/morphology and regolith weathering depth) in watersheds underlain by rhyolite and schist. Instrumented pedons in convergent, planar, and divergent landscape positions show distinct depth-dependent responses to precipitation events. Wetting front propagation, dissolved carbon flux and associated biogeochemical responses (e.g., pulses of CO2 production, O2 depletion, solute release) vary with topography, revealing the influence of lateral subsidies of water and carbon. The impacts of these episodes on the evolution of porous media heterogeneity is being investigated by statistical analysis of pore water chemistry, chemical/spectroscopic studies of solid phase organo-mineral products, sensor-derived water characteristic curves, and quantification of co-located microbial community activity/composition. Our results highlight the interacting effects of critical zone structure and convergent hydrologic flows in the evolution of biogeochemical control points.
What's in Your Water? An Educator's Guide to Water Quality.
ERIC Educational Resources Information Center
Constabile, Kerry, Comp.; Craig, Heidi, Comp.; O'Laughlin, Laura, Comp.; Reiss, Anne Bei, Comp.; Spencer, Liz, Comp.
This guide provides basic information on the Clean Water Act, watersheds, and testing for water quality, and presents four science lesson plans on water quality. Activities include: (1) "Introduction to Water Quality"; (2) "Chemical Water Quality Testing"; (3) "Biological Water Quality Testing"; and (4) "What Can We Do?" (YDS)
Lambing, John H.
2006-01-01
In accordance with guidelines set forth by the Office of Water Quality in the Water Resources Discipline of the U.S. Geological Survey (USGS), a quality-assurance plan has been created for use by the USGS Montana Water Science Center in conducting water-quality activities. This quality-assurance plan documents the standards, policies, and procedures used by the USGS Montana Water Science Center for activities related to the collection, processing, storage, analysis, and publication of water-quality data. The policies and procedures presented in this quality-assurance plan for water-quality activities complement the quality-assurance plans for surface-water and ground-water activities and suspended-sediment analysis.
Selective electrochemical generation of hydrogen peroxide from water oxidation
Viswanathan, Venkatasubramanian; Hansen, Heine A.; Norskov, Jens K.
2015-10-08
Water is a life-giving source, fundamental to human existence, yet over a billion people lack access to clean drinking water. The present techniques for water treatment such as piped, treated water rely on time and resource intensive centralized solutions. In this work, we propose a decentralized device concept that can utilize sunlight to split water into hydrogen and hydrogen peroxide. The hydrogen peroxide can oxidize organics while the hydrogen bubbles out. In enabling this device, we require an electrocatalyst that can oxidize water while suppressing the thermodynamically favored oxygen evolution and form hydrogen peroxide. Using density functional theory calculations, wemore » show that the free energy of adsorbed OH* can be used to determine selectivity trends between the 2e– water oxidation to H 2O 2 and the 4e– oxidation to O 2. We show that materials which bind oxygen intermediates sufficiently weakly, such as SnO 2, can activate hydrogen peroxide evolution. Furthermore, we present a rational design principle for the selectivity in electrochemical water oxidation and identify new material candidates that could perform H 2O 2 evolution selectively.« less
Friedel, Michael J.
1998-01-01
During the past 25 years, industry and government made large financial investments that resulted in better water quality across the Nation; however, many water-quality concerns remain. Following a 1986 pilot project, the U.S. Geological Survey began implementation of the National Water-Quality Assessment (NAWQA) Program in 1991. This program differs from other national water-quality assessment studies in that the NAWQA integrates monitoring of surface- and ground-water quality with the study of aquatic ecosystems. The goals of the NAWQA Program are to (1) describe current water-quality conditions for a large part of the Nation's freshwater streams and aquifers (water-bearing sediments and rocks), (2) describe how water quality is changing over time, and (3) improve our understanding of the primary natural and human factors affecting water quality.The Upper Illinois River Basin National Water- Quality Assessment (NAWQA) study will increase the scientific understanding of surface- and ground-water quality and the factors that affect water quality in the basin. The study also will provide information needed by water-resource managers to implement effective water-quality management actions and evaluate long-term changes in water quality.
Updating the Evidence for Oceans on Early Mars
NASA Technical Reports Server (NTRS)
Fairen, Alberto G.; Dohm, James M.; Oner, Tayfun; Ruiz, Javier; Rodriguez, Alexis P.; Schulze-Makuch, Dirk; Ormoe, Jens; McKay, Chris P.; Baker, Victor R.; Amils, Ricardo
2004-01-01
Different-sized bodies of water have been proposed to have occurred episodically in the lowlands of Mars throughout the planet's history, largely related to major stages of development of Tharsis and/or orbital obliquity. These water bodies range from large oceans in the Noachian-Early Hesperian, to a minor sea in the Late Hesperian, and dispersed lakes during the Amazonian. To evaluate the more recent discoveries regarding the oceanic possibility, here we perform a comprehensive analysis of the evolution of water on Mars, including: 1. Geological assessment of proposed shorelines; 2. A volumetric approximation to the plains-filing proposed oceans; 3. Geochemistry of the oceans and derived mineralogies; 4. Post-oceanic (i.e., Amazonian) evolution of the shorelines; and 5. Ultimate water evolution on Mars.
Evolution of monitoring for Giardia and Cryptosporidium in water.
Efstratiou, Artemis; Ongerth, Jerry; Karanis, Panagiotis
2017-10-15
This review describes the evolution of monitoring methodology for Cryptosporidium and Giardia in water since the 1970's. Methods in current use for Giardia and Cryptosporidium in water are highlighted, though attention is given to all available published methods by country and continent. The review is intended to stimulate research leading to future improvements and further developments in monitoring methodology for Giardia, Cryptosporidium and other waterborne protozoan parasites in water. Copyright © 2017. Published by Elsevier Ltd.
Water quality assessment with hierarchical cluster analysis based on Mahalanobis distance.
Du, Xiangjun; Shao, Fengjing; Wu, Shunyao; Zhang, Hanlin; Xu, Si
2017-07-01
Water quality assessment is crucial for assessment of marine eutrophication, prediction of harmful algal blooms, and environment protection. Previous studies have developed many numeric modeling methods and data driven approaches for water quality assessment. The cluster analysis, an approach widely used for grouping data, has also been employed. However, there are complex correlations between water quality variables, which play important roles in water quality assessment but have always been overlooked. In this paper, we analyze correlations between water quality variables and propose an alternative method for water quality assessment with hierarchical cluster analysis based on Mahalanobis distance. Further, we cluster water quality data collected form coastal water of Bohai Sea and North Yellow Sea of China, and apply clustering results to evaluate its water quality. To evaluate the validity, we also cluster the water quality data with cluster analysis based on Euclidean distance, which are widely adopted by previous studies. The results show that our method is more suitable for water quality assessment with many correlated water quality variables. To our knowledge, it is the first attempt to apply Mahalanobis distance for coastal water quality assessment.
2013-01-01
Background Developing a water quality index which is used to convert the water quality dataset into a single number is the most important task of most water quality monitoring programmes. As the water quality index setup is based on different local obstacles, it is not feasible to introduce a definite water quality index to reveal the water quality level. Findings In this study, an innovative software application, the Iranian Water Quality Index Software (IWQIS), is presented in order to facilitate calculation of a water quality index based on dynamic weight factors, which will help users to compute the water quality index in cases where some parameters are missing from the datasets. Conclusion A dataset containing 735 water samples of drinking water quality in different parts of the country was used to show the performance of this software using different criteria parameters. The software proved to be an efficient tool to facilitate the setup of water quality indices based on flexible use of variables and water quality databases. PMID:24499556
NASA Astrophysics Data System (ADS)
Chen, Yi
2018-03-01
The comprehensive water quality identification index method is able to assess the general water quality situation comprehensively and represent the water quality classification; water environment functional zone achieves pollution level and standard objectively and systematically. This paper selects 3 representative zones along deep-water channel of Guangzhou port and applies comprehensive water quality identification index method to calculate sea water quality monitoring data for different selected zones from year 2006 to 2014, in order to investigate the temporal variation of water quality along deep-water channel of Guangzhou port. The comprehensive water quality level from north to south presents an increased trend, and the water quality of the three zones in 2014 is much better than in 2006. This paper puts forward environmental protection measurements and suggestions for Pearl River Estuary, provides data support and theoretical basis for studied sea area pollution prevention and control.
Modeling chloride transport using travel time distributions at Plynlimon, Wales
NASA Astrophysics Data System (ADS)
Benettin, Paolo; Kirchner, James W.; Rinaldo, Andrea; Botter, Gianluca
2015-05-01
Here we present a theoretical interpretation of high-frequency, high-quality tracer time series from the Hafren catchment at Plynlimon in mid-Wales. We make use of the formulation of transport by travel time distributions to model chloride transport originating from atmospheric deposition and compute catchment-scale travel time distributions. The relevance of the approach lies in the explanatory power of the chosen tools, particularly to highlight hydrologic processes otherwise clouded by the integrated nature of the measured outflux signal. The analysis reveals the key role of residual storages that are poorly visible in the hydrological response, but are shown to strongly affect water quality dynamics. A significant accuracy in reproducing data is shown by our calibrated model. A detailed representation of catchment-scale travel time distributions has been derived, including the time evolution of the overall dispersion processes (which can be expressed in terms of time-varying storage sampling functions). Mean computed travel times span a broad range of values (from 80 to 800 days) depending on the catchment state. Results also suggest that, in the average, discharge waters are younger than storage water. The model proves able to capture high-frequency fluctuations in the measured chloride concentrations, which are broadly explained by the sharp transition between groundwaters and faster flows originating from topsoil layers. This article was corrected on 22 JUN 2015. See the end of the full text for details.
NASA Astrophysics Data System (ADS)
Bernard, Daniel; El Khattabi, Jamal; Lefevre, Emilie; Serhal, Hani; Bastin-Lacherez, Sabine; Shahrour, Isam
2008-01-01
In the north of France, high registers of nickel are sometimes recorded within the chalk aquifer. In a confined context, the presence of pyrite in the covering clays or in the marcasite nodules encrusted in the clay may constitute a natural source of trace metals. With an objective of sanitary control, the limits of chemical contents regulating the quality of water destined for human consumption have been lowered by the European Framework Directive in the field of water policy (2000/60/EC). As a result, nickel limits have been reduced from 50 to 20 μg/l. The analyses, carried out on three water catchment fields in our area of study, were centred on variable parameters (Eh, O2(d), pH, Conductivity, T°), major elements (SO4, NO3) and metals (Fe, Ni, Mn, Co). The acquired data enabled us to identify from one hand, the conditions which are presented within the site, special thanks to the evolution of nitrate and iron contents and on the other hand, the natural origin (geological) of nickel for two of the three sites studied based essentially on the evaluation of the Nickel/Cobalt ratio. Thus, on the first site, the evolution of nickel content and nitrate content showed the influence of the phenomenon of denitrification on the re-mobilisation of the nickel. Whereas on the second site, a high variation of total iron content and oxygen dissolved in solution highlighted a particular phenomenon of oxidation of the pyrite through molecular oxygen. Finally, the correlation with the sulphates clearly showed behaviour of the nickel, once released, that was entirely dependent on the phenomenon of adsorption on the iron and manganese hydroxides.
NASA Astrophysics Data System (ADS)
Ala-aho, P. O. A.; Tetzlaff, D.; Laudon, H.; McNamara, J. P.; Soulsby, C.
2016-12-01
We use the Spatially distributed Tracer-Aided Rainfall-Runoff (STARR) modelling framework to explore non-stationary flow and isotope response in three northern headwater catchments. The model simulates dynamic, spatially variable tracer concentration in different water stores and fluxes within a catchment, which can constrain internal catchment mixing processes, flow paths and associated water ages. To date, a major limitation in using such models in snow-dominated catchments has been the difficulties in paramaterising the isotopic transformations in snowpack accumulation and melt. We use high quality long term datasets for hydrometrics and stable water isotopes collected in three northern study catchments for model calibration and testing. The three catchments exhibit different hydroclimatic conditions, soil and vegetation types, and topographic relief, which brings about variable degree of snow dominance across the catchments. To account for the snow influence we develop novel formulations to estimate the isotope evolution in the snowpack and melt. Algorithms for the isotopic evolution parameterize an isotopic offset between snow evaporation and melt fluxes and the remaining snow storage. The model for each catchment is calibrated to match both streamflow and tracer concentration at the stream outlet to ensure internal consistency of the system behaviour. The model is able to reproduce the streamflow along with the spatio-temporal differences in tracer concentrations across the three studies catchments reasonably well. Incorporating the spatially distributed snowmelt processes and associated isotope transformations proved essential in capturing the stream tracer reponse for strongly snow-influenced cathments. This provides a transferrable tool which can be used to understand spatio-temporal variability of mixing and water ages for different storages and flow paths in other snow influenced, environments.
Comparison of hydrothermal activity between the Adriatic and the Red Sea rift margins
NASA Astrophysics Data System (ADS)
Ball, Philip; Incerpi, Nicolò; Birkle, Peter; Lacsamana, Elizabeth; Manatschal, Gianreto; Agar, Susan; Zhang, Shuo; Borsato, Ron
2017-04-01
Detailed field studies, and access to high-quality seismic reflection and refraction data have led to an improved understanding of the architecture and evolution of magma poor and magma rich margins. Associated with the spatial-temporal evolution of the rift, it is evident that there are evolving, extensive, fluid-rock interactions due to the infiltration of fluids within the sediment, basement and lithospheric mantle. Key questions therefore arise: What are the different fluid-rock reactions that can be typed to different geodynamic stages of the rift evolution? What are their compositions and how do they interact with their environment (basement, sediments, evaporites, hydrosphere, and magmatism)? What are the implications for the evolution of the margin rheology, thermal structure, depositional environments/organic matter maturity, and reservoir quality? The Adriatic paleo-rifted margin is preserved in both SE Switzerland and northern Italy. The field exposures provide a unique opportunity to study the fluid flow history of a hyperextended magma poor extensional margin. Analysis of breccias, cement veins and replacement minerals reveal that the margin records a complex, long-lasting history of dolomitization, calcification and silicification during the Jurassic rifting. The Red Sea by contrast is a young rifted margin. It differs from the paleo-Adriatic margin by several characteristics: volcanism is more evident, and syn-tectonic sediments, including evaporites (halite and anhydrite) are thicker. Several core and fluid samples are available from both onshore and offshore wells, which reveal rift-related hydrothermal alteration. In addition, we find evidence for the presence of an extreme dynamic hydraulic system with infiltration of surface water into sub-salt units during Late Pleistocene. In this study we present results from petrographic and geochemical analysis of basement and sedimentary rocks from Adriatic field-derived samples and core/subsurface fluid samples for the Eastern Red Sea margin. The results are presented using rift domain interpretations, thereby enabling the simple comparison of the observed hydrothermal alteration within a first-order (spatial temporal) rift geodynamic framework.
The role of wellbore remediation on the evolution of groundwater quality from CO₂ and brine leakage
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mansoor, Kayyum; Carroll, Susan A.; Sun, Yunwei
Long-term storage of CO₂ in underground reservoirs requires a careful assessment to evaluate risk to groundwater sources. The focus of this study is to assess time-frames required to restore water quality to pre-injection levels based on output from complex reactive transport simulations that exhibit plume retraction within a 200-year simulation period. We examined the relationship between plume volume, cumulative injected CO₂ mass, and permeability. The role of mitigation was assessed by projecting falloffs in plume volumes from their maximum peak levels with a Gaussian function to estimate plume recovery times to reach post-injection groundwater compositions. The results show a strongmore » correlation between cumulative injected CO₂ mass and maximum plume pH volumes and a positive correlation between CO₂ flux, cumulative injected CO₂, and plume recovery times, with secondary dependence on permeability.« less
The role of wellbore remediation on the evolution of groundwater quality from CO₂ and brine leakage
Mansoor, Kayyum; Carroll, Susan A.; Sun, Yunwei
2014-12-31
Long-term storage of CO₂ in underground reservoirs requires a careful assessment to evaluate risk to groundwater sources. The focus of this study is to assess time-frames required to restore water quality to pre-injection levels based on output from complex reactive transport simulations that exhibit plume retraction within a 200-year simulation period. We examined the relationship between plume volume, cumulative injected CO₂ mass, and permeability. The role of mitigation was assessed by projecting falloffs in plume volumes from their maximum peak levels with a Gaussian function to estimate plume recovery times to reach post-injection groundwater compositions. The results show a strongmore » correlation between cumulative injected CO₂ mass and maximum plume pH volumes and a positive correlation between CO₂ flux, cumulative injected CO₂, and plume recovery times, with secondary dependence on permeability.« less
Fujisawa, Tomochika; Vogler, Alfried P; Barraclough, Timothy G
2015-01-22
Comparative analysis is a potentially powerful approach to study the effects of ecological traits on genetic variation and rate of evolution across species. However, the lack of suitable datasets means that comparative studies of correlates of genetic traits across an entire clade have been rare. Here, we use a large DNA-barcode dataset (5062 sequences) of water beetles to test the effects of species ecology and geographical distribution on genetic variation within species and rates of molecular evolution across species. We investigated species traits predicted to influence their genetic characteristics, such as surrogate measures of species population size, latitudinal distribution and habitat types, taking phylogeny into account. Genetic variation of cytochrome oxidase I in water beetles was positively correlated with occupancy (numbers of sites of species presence) and negatively with latitude, whereas substitution rates across species depended mainly on habitat types, and running water specialists had the highest rate. These results are consistent with theoretical predictions from nearly-neutral theories of evolution, and suggest that the comparative analysis using large databases can give insights into correlates of genetic variation and molecular evolution.
Laser-Induced Graphene Formation on Wood.
Ye, Ruquan; Chyan, Yieu; Zhang, Jibo; Li, Yilun; Han, Xiao; Kittrell, Carter; Tour, James M
2017-10-01
Wood as a renewable naturally occurring resource has been the focus of much research and commercial interests in applications ranging from building construction to chemicals production. Here, a facile approach is reported to transform wood into hierarchical porous graphene using CO 2 laser scribing. Studies reveal that the crosslinked lignocellulose structure inherent in wood with higher lignin content is more favorable for the generation of high-quality graphene than wood with lower lignin content. Because of its high electrical conductivity (≈10 Ω per square), graphene patterned on wood surfaces can be readily fabricated into various high-performance devices, such as hydrogen evolution and oxygen evolution electrodes for overall water splitting with high reaction rates at low overpotentials, and supercapacitors for energy storage with high capacitance. The versatility of this technique in formation of multifunctional wood hybrids can inspire both research and industrial interest in the development of wood-derived graphene materials and their nanodevices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Sherwood, Christopher R.
2006-01-01
A U.S. Geological Survey (USGS) Coastal and Marine Geology (CMG) Modeling Workshop was held to discuss the general topic of coastal modeling, defined broadly to include circulation, waves, sediment transport, water quality, ecology, sediment diagenesis, morphology change, and coastal evolution, on scales ranging from seconds and a few centimeters (individual ripples) to centuries (coastal evolution) and thousands of kilometers (tsunami propagation). The workshop was convened at the suggestion of CMG Program Management to improve communication among modelers and model users, assess modeling-related activities being conducted at the three centers (Florida Integrated Science Center, FISC; Pacific Marine Science Center; PMSC; and Woods Hole Science Center; WHSC), and develop goals, strategies, and plans for future modeling activities. The workshop represents a step toward developing a five-year strategic plan, and was timed to provide input for the FY06 prospectus. The workshop was held at the USGS Pacific Marine Science Center in Santa Cruz on March 22-23, 2005.
NASA Astrophysics Data System (ADS)
Koutiva, Ifigeneia; Makropoulos, Christos
2015-04-01
The urban water system's sustainable evolution requires tools that can analyse and simulate the complete cycle including both physical and cultural environments. One of the main challenges, in this regard, is the design and development of tools that are able to simulate the society's water demand behaviour and the way policy measures affect it. The effects of these policy measures are a function of personal opinions that subsequently lead to the formation of people's attitudes. These attitudes will eventually form behaviours. This work presents the design of an ABM tool for addressing the social dimension of the urban water system. The created tool, called Urban Water Agents' Behaviour (UWAB) model, was implemented, using the NetLogo agent programming language. The main aim of the UWAB model is to capture the effects of policies and environmental pressures to water conservation behaviour of urban households. The model consists of agents representing urban households that are linked to each other creating a social network that influences the water conservation behaviour of its members. Household agents are influenced as well by policies and environmental pressures, such as drought. The UWAB model simulates behaviour resulting in the evolution of water conservation within an urban population. The final outcome of the model is the evolution of the distribution of different conservation levels (no, low, high) to the selected urban population. In addition, UWAB is implemented in combination with an existing urban water management simulation tool, the Urban Water Optioneering Tool (UWOT) in order to create a modelling platform aiming to facilitate an adaptive approach of water resources management. For the purposes of this proposed modelling platform, UWOT is used in a twofold manner: (1) to simulate domestic water demand evolution and (2) to simulate the response of the water system to the domestic water demand evolution. The main advantage of the UWAB - UWOT model integration is that it allows the investigation of the effects of different water demand management strategies to an urban population's water demand behaviour and ultimately the effects of these policies to the volume of domestic water demand and the water resources system. The proposed modelling platform is optimised to simulate the effects of water policies during the Athens drought period of 1988-1994. The calibrated modelling platform is then applied to evaluate scenarios of water supply, water demand and water demand management strategies.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-04
... aquatic life water quality criteria applicable to waters of New Jersey, Puerto Rico, and California's San Francisco Bay. In 1992, EPA promulgated the National Toxics Rule or NTR to establish numeric water quality... Water Quality Standards; Withdrawal of Certain Federal Water Quality Criteria Applicable to California...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Viswanathan, Venkatasubramanian; Hansen, Heine A.; Norskov, Jens K.
Water is a life-giving source, fundamental to human existence, yet over a billion people lack access to clean drinking water. The present techniques for water treatment such as piped, treated water rely on time and resource intensive centralized solutions. In this work, we propose a decentralized device concept that can utilize sunlight to split water into hydrogen and hydrogen peroxide. The hydrogen peroxide can oxidize organics while the hydrogen bubbles out. In enabling this device, we require an electrocatalyst that can oxidize water while suppressing the thermodynamically favored oxygen evolution and form hydrogen peroxide. Using density functional theory calculations, wemore » show that the free energy of adsorbed OH* can be used to determine selectivity trends between the 2e– water oxidation to H 2O 2 and the 4e– oxidation to O 2. We show that materials which bind oxygen intermediates sufficiently weakly, such as SnO 2, can activate hydrogen peroxide evolution. Furthermore, we present a rational design principle for the selectivity in electrochemical water oxidation and identify new material candidates that could perform H 2O 2 evolution selectively.« less
Hydrogen Isotopes Record the History of the Martian Hydrosphere and Atmosphere
NASA Technical Reports Server (NTRS)
Usui, T.; Simon, J. I.; Jones, J. H.; Kurokawa, H.; Sato, M.; Alexander, C. M. O'D; Wang, J.
2015-01-01
The surface geology and geomorphology of Mars indicates that it was once warm enough to maintain a large body of liquid water on its surface, though such a warm environment might have been transient. The transition to the present cold and dry Mars is closely linked to the history of surface water, yet the evolution of surficial water is poorly constrained. This study presents insights from hydrogen isotopes for the origin and evolution of Martian water reservoirs.
Conn, Kathleen E.; Huffman, Raegan L.; Barton, Cynthia
2017-05-08
In accordance with guidelines set forth by the Office of Water Quality in the Water Mission Area of the U.S. Geological Survey, a quality-assurance plan has been created for use by the Washington Water Science Center (WAWSC) in conducting water-quality activities. This qualityassurance plan documents the standards, policies, and procedures used by the WAWSC for activities related to the collection, processing, storage, analysis, and publication of water-quality data. The policies and procedures documented in this quality-assurance plan for water-quality activities complement the quality-assurance plans for surface-water and groundwater activities at the WAWSC.
Army Corps of Engineers: Water Resource Authorizations, Appropriations, and Activities
2014-07-01
Assistance Authorities ........................................................................... 11 Appendixes Appendix. Evolution of the Its...projects (e.g., municipal water and wastewater treatment systems) and other nontraditional activities. The Appendix provides more on the evolution of...feasibility by the Secretary of the Army.13 10 General Robert B. Flowers , Army Corps
Advances in the hydrogeochemistry and microbiology of acid mine waters
Nordstrom, D. Kirk
2000-01-01
The last decade has witnessed a plethora of research related to the hydrogeochemistry and microbiology of acid mine waters and associated tailings and waste-rock waters. Numerous books, reviews, technical papers, and proceedings have been published that examine the complex bio-geochemical process of sulfide mineral oxidation, develop and apply geochemical models to site characterization, and characterize the microbial ecology of these environments. This review summarizes many of these recent works, and provides references for those investigating this field. Comparisons of measured versus calculated Eh and measured versus calculated pH for water samples from several field sites demonstrate the reliability of some current geochemical models for aqueous speciation and mass balances. Geochemical models are not, however, used to predict accurately time-dependent processes but to improve our understanding of these systems and to constrain possible processes that contribute to actual or potential water quality issues. Microbiological studies are demonstrating that there is much we have yet to learn about the types of different microorganisms and their function and ecology in mine-waste environments. A broad diversity of green algae, bacteria, archaea, yeasts, and fungi are encountered in acid mine waters, and a better understanding of their ecology and function may potentially enhance remediation possibilities as well as our understanding of the evolution of life.
NASA Astrophysics Data System (ADS)
Morgenstern, Uwe; Daughney, Christopher J.
2012-08-01
SummaryWe identified natural baseline groundwater quality and impacts caused by land use intensification by relating groundwater chemistry with water age. Tritium, the most direct tracer for groundwater dating, including the time of water passage through the unsaturated zone, was overwhelmed over the recent decades by contamination from bomb-tritium from nuclear weapons testing in the early 1960s. In the Southern Hemisphere, this situation has changed now with the fading of the bomb-tritium, and tritium has become a tool for accurate groundwater dating. Tritium dating will become efficient also in the Northern Hemisphere over the next decade. Plotting hydrochemistry and field parameters versus groundwater age allowed us to identify those parameters that have increasing concentrations with age and are therefore from geological sources. These indicators for natural groundwater evolution are: Na, HCO3, SiO2, F, PO4, the redox-sensitive elements and compounds Fe, Mn, NH4, CH4, and pH and conductivity. In young groundwater that was recharged after the intensification of agriculture, nitrate, sulphate, CFC-11 and CFC-12, and pesticides are the most representative indicators for the impact of land-use intensification on groundwater quality, with 66% of the sites showing such an impact. Elevated concentrations of nitrate in oxic groundwater allowed us to reconstruct the timing and magnitude of the impact of land-use intensification on groundwater which in New Zealand occurred in two stages. Old pristine groundwater reflects the natural baseline quality. A transition to slightly elevated concentration due to low-intensity land-use was observed in groundwater recharged since around 1880. A sharp increase in nitrate and other agrochemicals due to high-intensity agriculture was observed in groundwater recharged since 1955. The threshold concentrations that distinguish natural baseline quality water from low-intensity land-use water, and low-intensity from high intensity land-use water, are 0.25 and 2.5 mg/L NO3-N, respectively. The change in groundwater quality from pristine baseline to low-intensity impact around 1880 coincides with the start of the meat export industry. The change in groundwater quality from low to high intensity landuse impact around 1955 coincides with the start of industrialised agriculture. No elevated levels of phosphate, a main compound in agricultural fertilisers and, together with nitrogen, a trigger of algae blooms in lakes, were found in young groundwater. This implies that fertiliser phosphate from non-point sources is still retained in the soil and has not yet reached the saturated groundwater systems. The source of elevated PO4, observed only in old groundwater, is therefore due purely to natural geochemical factors.
Research on the Relationship between Water Diversion and Water Quality of Xuanwu Lake, China.
Song, Weiwei; Xu, Qing; Fu, Xingqian; Zhang, Peng; Pang, Yong; Song, Dahao
2018-06-14
Water diversion is often used to improve water quality to reach the standard of China in the short term. However, this large amount of water diversion can not only improve the water quality, but also lead to a decline in the water quality (total phosphorus, total nitrogen) of Xuanwu Lake. Through theoretical analysis, the relationship between water quality and water diversion is established. We also found that the multiplication of the pollutant degradation coefficient ( K ) and the water residence time ( T ) is a constant ( N ), K⋅T=N. The water quality changed better at first, with the increase of inflow discharge, and then became worse, and the optimal water quality inflow discharge is 180,000 m³/day. By constructing two-dimensional hydrodynamic and water quality models, the optimal diversion water plan is calculated. Through model calculations, it can be seen that reducing the inflow discharge makes the water residence time longer (15.3 days changed to 23.8 days). Thereby, increasing the degradation of pollutants, and thus improving water quality. Compared with other wind directions, the southwest wind makes the water quality of Xuanwu Lake the most uniform. The concentration of water quality first became smaller and then became larger, as the wind speed increased, and eventually became constant. Implementing these results for water quality improvement in small and medium lakes will significantly reduce the cost of water diversion.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Malamud, Uri; Perets, Hagai B., E-mail: uri.mal@tx.technion.ac.il, E-mail: hperets@physics.technion.ac.il
Most observations of polluted white dwarf atmospheres are consistent with accretion of water-depleted planetary material. Among tens of known cases, merely two involve accretion of objects that contain a considerable mass fraction of water. The purpose of this study is to investigate the relative scarcity of these detections. Based on a new and highly detailed model, we evaluate the retention of water inside icy minor planets during the high-luminosity stellar evolution that follows the main sequence. Our model fully considers the thermal, physical, and chemical evolution of icy bodies, following their internal differentiation as well as water depletion, from themore » moment of their birth and through all stellar evolution phases preceding the formation of the white dwarf. We also account for different initial compositions and formation times. Our results differ from previous studies, which have either underestimated or overestimated water retention. We show that water can survive in a variety of circumstances and in great quantities, and therefore other possibilities are discussed in order to explain the infrequency of water detection. We predict that the sequence of accretion is such that water accretes earlier, and more rapidly, than the rest of the silicate disk, considerably reducing the chance of its detection in H-dominated atmospheres. In He-dominated atmospheres, the scarcity of water detections could be observationally biased. It implies that the accreted material is typically intrinsically dry, which may be the result of the inside-out depopulation sequence of minor planets.« less
NASA Technical Reports Server (NTRS)
Kahre, M. A.
2015-01-01
The dust and water cycles are crucial to the current Martian climate, and they are coupled through cloud formation. Dust strongly impacts the thermal structure of the atmosphere and thus greatly affects atmospheric circulation, while clouds provide radiative forcing and control the hemispheric exchange of water through the modification of the vertical distributions of water and dust. Recent improvements in the quality and sophistication of both observations and climate models allow for a more comprehensive understanding of how the interaction between the dust and water cycles (through cloud formation) affects the dust and water cycles individually. We focus here on the effects of clouds on the vertical distribution of dust and water, and how those vertical distributions control the net meridional transport of water. For this study, we utilize observations of temperature, dust and water ice from the Mars Climate Sounder (MCS) on the Mars Reconnaissance Orbiter (MRO) combined with the NASA ARC Mars Global Climate Model (MGCM). We demonstrate that the magnitude and nature of the net meridional transport of water between the northern and southern hemispheres during NH summer is sensitive to the vertical structure of the simulated aphelion cloud belt. We further examine how clouds influence the atmospheric thermal structure and thus the vertical structure of the cloud belt. Our goal is to identify and understand the importance of radiative/dynamic feedbacks due to the physical processes involved with cloud formation and evolution on the current climate of Mars.
NASA Technical Reports Server (NTRS)
Kahre, M. A.; Haberle, R. M.; Hollingsworth, J. L.; Brecht, A. S.; Urata, R.
2015-01-01
The dust and water cycles are critical to the current Martian climate, and they interact with each other through cloud formation. Dust modulates the thermal structure of the atmosphere and thus greatly influences atmospheric circulation. Clouds provide radiative forcing and control the net hemispheric transport of water through the alteration of the vertical distributions of water and dust. Recent advancements in the quality and sophistication of both climate models and observations enable an increased understanding of how the coupling between the dust and water cycles (through cloud formation) impacts the dust and water cycles. We focus here on the effects of clouds on the vertical distributions of dust and water and how those vertical distributions control the net meridional transport of water. We utilize observations of temperature, dust and water ice from the Mars Climate Sounder (MCS) on the Mars Reconnaissance Orbiter (MRO) and the NASA ARC Mars Global Climate Model (MGCM) to show that the magnitude and nature of the hemispheric exchange of water during NH summer is sensitive to the vertical structure of the simulated aphelion cloud belt. Further, we investigate how clouds influence atmospheric temperatures and thus the vertical structure of the cloud belt. Our goal is to isolate and understand the importance of radiative/dynamic feedbacks due to the physical processes involved with cloud formation and evolution on the current climate of Mars.
NASA Astrophysics Data System (ADS)
Kahre, Melinda A.; Haberle, Robert M.; Hollingsworth, Jeffery L.; Brecht, Amanda S.; Urata, Richard A.
2015-11-01
The dust and water cycles are critical to the current Martian climate, and they interact with each other through cloud formation. Dust modulates the thermal structure of the atmosphere and thus greatly influences atmospheric circulation. Clouds provide radiative forcing and control the net hemispheric transport of water through the alteration of the vertical distributions of water and dust. Recent advancements in the quality and sophistication of both climate models and observations enable an increased understanding of how the coupling between the dust and water cycles (through cloud formation) impacts the dust and water cycles. We focus here on the effects of clouds on the vertical distributions of dust and water and how those vertical distributions control the net meridional transport of water. We utilize observations of temperature, dust and water ice from the Mars Climate Sounder (MCS) on the Mars Reconnaissance Orbiter (MRO) and the NASA ARC Mars Global Climate Model (MGCM) to show that the magnitude and nature of the hemispheric exchange of water during NH summer is sensitive to the vertical structure of the simulated aphelion cloud belt. Further, we investigate how clouds influence atmospheric temperatures and thus the vertical structure of the cloud belt. Our goal is to isolate and understand the importance of radiative/dynamic feedbacks due to the physical processes involved with cloud formation and evolution on the current climate of Mars.
Gu, Qing; Wang, Ke; Li, Jiadan; Ma, Ligang; Deng, Jinsong; Zheng, Kefeng; Zhang, Xiaobin; Sheng, Li
2015-01-01
It is widely accepted that characterizing the spatio-temporal trends of water quality parameters and identifying correlated variables with water quality are indispensable for the management and protection of water resources. In this study, cluster analysis was used to classify 56 typical drinking water reservoirs in Zhejiang Province into three groups representing different water quality levels, using data of four water quality parameters for the period 2006–2010. Then, the spatio-temporal trends in water quality were analyzed, assisted by geographic information systems (GIS) technology and statistical analysis. The results indicated that the water quality showed a trend of degradation from southwest to northeast, and the overall water quality level was exacerbated during the study period. Correlation analysis was used to evaluate the relationships between water quality parameters and ten independent variables grouped into four categories (land use, socio-economic factors, geographical features, and reservoir attributes). According to the correlation coefficients, land use and socio-economic indicators were identified as the most significant factors related to reservoir water quality. The results offer insights into the spatio-temporal variations of water quality parameters and factors impacting the water quality of drinking water reservoirs in Zhejiang Province, and they could assist managers in making effective strategies to better protect water resources. PMID:26492263
Gu, Qing; Wang, Ke; Li, Jiadan; Ma, Ligang; Deng, Jinsong; Zheng, Kefeng; Zhang, Xiaobin; Sheng, Li
2015-10-20
It is widely accepted that characterizing the spatio-temporal trends of water quality parameters and identifying correlated variables with water quality are indispensable for the management and protection of water resources. In this study, cluster analysis was used to classify 56 typical drinking water reservoirs in Zhejiang Province into three groups representing different water quality levels, using data of four water quality parameters for the period 2006-2010. Then, the spatio-temporal trends in water quality were analyzed, assisted by geographic information systems (GIS) technology and statistical analysis. The results indicated that the water quality showed a trend of degradation from southwest to northeast, and the overall water quality level was exacerbated during the study period. Correlation analysis was used to evaluate the relationships between water quality parameters and ten independent variables grouped into four categories (land use, socio-economic factors, geographical features, and reservoir attributes). According to the correlation coefficients, land use and socio-economic indicators were identified as the most significant factors related to reservoir water quality. The results offer insights into the spatio-temporal variations of water quality parameters and factors impacting the water quality of drinking water reservoirs in Zhejiang Province, and they could assist managers in making effective strategies to better protect water resources.
Puente, Gabriela F; García-Martínez, Pablo; Bonetto, Fabián J
2007-01-01
We present theoretical calculations of an argon bubble in a liquid solution of 85%wt sulfuric acid and 15%wt water in single-bubble sonoluminescence. We used a model without free parameters to be adjusted. We predict from first principles the region in parameter space for stable bubble evolution, the temporal evolution of the bubble radius, the maximum temperature, pressures, and the light spectra due to thermal emissions. We also used a partial differential equation based model (hydrocode) to compute the temperature and pressure evolutions at the center of the bubble during maximum compression. We found the behavior of this liquid mixture to be very different from water in several aspects. Most of the models in sonoluminescence were compared with water experimental results.
Disk Evolution and the Fate of Water
NASA Astrophysics Data System (ADS)
Hartmann, Lee; Ciesla, Fred; Gressel, Oliver; Alexander, Richard
2017-10-01
We review the general theoretical concepts and observational constraints on the distribution and evolution of water vapor and ice in protoplanetary disks, with a focus on the Solar System. Water is expected to freeze out at distances greater than 1-3 AU from solar-type central stars; more precise estimates are difficult to obtain due to uncertainties in the complex processes involved in disk evolution, including dust growth, settling, and radial drift, and the level of turbulence and viscous dissipation within disks. Interferometric observations are now providing constraints on the positions of CO snow lines, but extrapolation to the unresolved regions where water ice sublimates will require much better theoretical understanding of mass and angular momentum transport in disks as well as more refined comparison of observations with sophisticated disk models.
Cabin Air Quality On Board Mir and the International Space Station: A Comparison
NASA Technical Reports Server (NTRS)
Macatangay, Ariel; Perry, Jay L.
2007-01-01
The maintenance of the cabin atmosphere aboard spacecraft is critical not only to its habitability but also to its function. Ideally, air quality can be maintained by striking a proper balance between the generation and removal of contaminants. Both very dynamic processes, the balance between generation and removal can be difficult to maintain and control because the state of the cabin atmosphere is in constant evolution responding to different perturbations. Typically, maintaining a clean cabin environment on board crewed spacecraft and space habitats is the central function of the environmental control and life support (ECLS) system. While active air quality control equipment is deployed on board every vehicle to remove carbon dioxide, water vapor, and trace chemical components from the cabin atmosphere, perturbations associated with logistics, vehicle construction and maintenance, and ECLS system configuration influence the resulting cabin atmospheric quality. The air-quality data obtained from the International Space Station (ISS) and NASA-Mir programs provides a wealth of information regarding the maintenance of the cabin atmosphere aboard long-lived space habitats. A comparison of the composition of the trace chemical contaminant load is presented. Correlations between ground-based and in-flight operations that influence cabin atmospheric quality are identified and discussed, and observations on cabin atmospheric quality during the NASA-Mir expeditions and the International Space Station are explored.
Matrix quality and disturbance frequency drive evolution of species behavior at habitat boundaries.
Martin, Amanda E; Fahrig, Lenore
2015-12-01
Previous theoretical studies suggest that a species' landscape should influence the evolution of its dispersal characteristics, because landscape structure affects the costs and benefits of dispersal. However, these studies have not considered the evolution of boundary crossing, that is, the tendency of animals to cross from habitat to nonhabitat ("matrix"). It is important to understand this dispersal behavior, because of its effects on the probability of population persistence. Boundary-crossing behavior drives the rate of interaction with matrix, and thus, it influences the rate of movement among populations and the risk of dispersal mortality. We used an individual-based, spatially explicit model to simulate the evolution of boundary crossing in response to landscape structure. Our simulations predict higher evolved probabilities of boundary crossing in landscapes with more habitat, less fragmented habitat, higher-quality matrix, and more frequent disturbances (i.e., fewer generations between local population extinction events). Unexpectedly, our simulations also suggest that matrix quality and disturbance frequency have much stronger effects on the evolution of boundary crossing than either habitat amount or habitat fragmentation. Our results suggest that boundary-crossing responses are most affected by the costs of dispersal through matrix and the benefits of escaping local extinction events. Evolution of optimal behavior at habitat boundaries in response to the landscape may have implications for species in human-altered landscapes, because this behavior may become suboptimal if the landscape changes faster than the species' evolutionary response to that change. Understanding how matrix quality and habitat disturbance drive evolution of behavior at boundaries, and how this in turn influences the extinction risk of species in human-altered landscapes should help us identify species of conservation concern and target them for management.
Monitoring and Assessment of Youshui River Water Quality in Youyang
NASA Astrophysics Data System (ADS)
Wang, Xue-qin; Wen, Juan; Chen, Ping-hua; Liu, Na-na
2018-02-01
By monitoring the water quality of Youshui River from January 2016 to December 2016, according to the indicator grading and the assessment standard of water quality, the formulas for 3 types water quality indexes are established. These 3 types water quality indexes, the single indicator index Ai, single moment index Ak and the comprehensive water quality index A, were used to quantitatively evaluate the quality of single indicator, the water quality and the change of water quality with time. The results show that, both total phosphorus and fecal coliform indicators exceeded the standard, while the other 16 indicators measured up to the standard. The water quality index of Youshui River is 0.93 and the grade of water quality comprehensive assessment is level 2, which indicated that the water quality of Youshui River is good, and there is room for further improvement. To this end, several protection measures for Youshui River environmental management and pollution treatment are proposed.
Zhang, Peili; Li, Lin; Nordlund, Dennis; Chen, Hong; Fan, Lizhou; Zhang, Biaobiao; Sheng, Xia; Daniel, Quentin; Sun, Licheng
2018-01-26
Electrochemical water splitting requires efficient water oxidation catalysts to accelerate the sluggish kinetics of water oxidation reaction. Here, we report a promisingly dendritic core-shell nickel-iron-copper metal/metal oxide electrode, prepared via dealloying with an electrodeposited nickel-iron-copper alloy as a precursor, as the catalyst for water oxidation. The as-prepared core-shell nickel-iron-copper electrode is characterized with porous oxide shells and metallic cores. This tri-metal-based core-shell nickel-iron-copper electrode exhibits a remarkable activity toward water oxidation in alkaline medium with an overpotential of only 180 mV at a current density of 10 mA cm -2 . The core-shell NiFeCu electrode exhibits pH-dependent oxygen evolution reaction activity on the reversible hydrogen electrode scale, suggesting that non-concerted proton-electron transfers participate in catalyzing the oxygen evolution reaction. To the best of our knowledge, the as-fabricated core-shell nickel-iron-copper is one of the most promising oxygen evolution catalysts.
Water quality assessment of Australian ports using water quality evaluation indices
Jahan, Sayka
2017-01-01
Australian ports serve diverse and extensive activities, such as shipping, tourism and fisheries, which may all impact the quality of port water. In this work water quality monitoring at different ports using a range of water quality evaluation indices was applied to assess the port water quality. Seawater samples at 30 stations in the year 2016–2017 from six ports in NSW, Australia, namely Port Jackson, Botany, Kembla, Newcastle, Yamba and Eden, were investigated to determine the physicochemical and biological variables that affect the port water quality. The large datasets obtained were designed to determine the Water Quality Index, Heavy metal Evaluation Index, Contamination Index and newly developed Environmental Water Quality Index. The study revealed medium water quality index and high and medium heavy metal evaluation index at three of the study ports and high contamination index in almost all study ports. Low level dissolved oxygen and higher level of total dissolved solids, turbidity, fecal coliforms, copper, iron, lead, zinc, manganese, cadmium and cobalt are mainly responsible for the poor water qualities of the port areas. Good water quality at the background samples indicated that various port activities are the likely cause for poor water quality inside the port area. PMID:29244876
NASA Astrophysics Data System (ADS)
Zhang, Qian; Feng, Minquan; Hao, Xiaoyan
2018-03-01
[Objective] Based on the water quality historical data from the Zhangze Reservoir from the last five years, the water quality was assessed by the integrated water quality identification index method and the Nemerow pollution index method. The results of different evaluation methods were analyzed and compared and the characteristics of each method were identified.[Methods] The suitability of the water quality assessment methods were compared and analyzed, based on these results.[Results] the water quality tended to decrease over time with 2016 being the year with the worst water quality. The sections with the worst water quality were the southern and northern sections.[Conclusion] The results produced by the traditional Nemerow index method fluctuated greatly in each section of water quality monitoring and therefore could not effectively reveal the trend of water quality at each section. The combination of qualitative and quantitative measures of the comprehensive pollution index identification method meant it could evaluate the degree of water pollution as well as determine that the river water was black and odorous. However, the evaluation results showed that the water pollution was relatively low.The results from the improved Nemerow index evaluation were better as the single indicators and evaluation results are in strong agreement; therefore the method is able to objectively reflect the water quality of each water quality monitoring section and is more suitable for the water quality evaluation of the reservoir.
Hydrochemical Impacts of CO2 Leakage on Fresh Groundwater: a Field Scale Experiment
NASA Astrophysics Data System (ADS)
Lions, J.; Gal, F.; Gombert, P.; Lafortune, S.; Darmoul, Y.; Prevot, F.; Grellier, S.; Squarcioni, P.
2013-12-01
One of the questions related to the emerging technology for Carbon Geological Storage concerns the risk of CO2 migration beyond the geological storage formation. In the event of leakage toward the surface, the CO2 might affect resources in neighbouring formations (geothermal or mineral resources, groundwater) or even represent a hazard for human activities at the surface or in the subsurface. In view of the preservation of the groundwater resources mainly for human consumption, this project studies the potential hydrogeochemical impacts of CO2 leakage on fresh groundwater quality. One of the objectives is to characterize the bio-geochemical mechanisms that may impair the quality of fresh groundwater resources in case of CO2 leakage. To reach the above mentioned objectives, this project proposes a field experiment to characterize in situ the mechanisms that could impact the water quality, the CO2-water-rock interactions and also to improve the monitoring methodology by controlled CO2 leakage in shallow aquifer. The tests were carried out in an experimental site in the chalk formation of the Paris Basin. The site is equipped with an appropriate instrumentation and was previously characterized (8 piezometers, 25 m deep and 4 piezairs 11 m deep). The injection test was preceded by 6 months of monitoring in order to characterize hydrodynamics and geochemical baselines of the site (groundwater, vadose and soil). Leakage into groundwater is simulated via the injection of a small quantity of food-grade CO2 (~20 kg dissolved in 10 m3 of water) in the injection well at a depth of about 20 m. A plume of dissolved CO2 is formed and moves downward according to the direction of groundwater flow and probably by degassing in part to the surface. During the injection test, hydrochemical monitoring of the aquifer is done in situ and by sampling. The parameters monitored in the groundwater are the piezometric head, temperature, pH and electrical conductivity. Analysis on water samples provide chemical elements (major, minor and trace metals), dissolved gases, microbiological diversity and isotopes (13C). The evolution of the composition of the groundwater in terms of major elements, trace elements and isotope signatures is interpreted in terms of geochemical mechanisms, and the water-rock-CO2 interactions are characterized. Modification of the chemical composition of water in the aquifer due to CO2 injection is assessed in term of groundwater quality i.e. metal element release and the possibility of exceeding references and quality of water for human consumption. One outcome of the CIPRES project will be to highlight mechanisms that can impact groundwater quality when a CO2 leakage occurs and to propose recommendations to prevent or/and eliminate negative effects and any risks to the environment and human health. This project is partially funded by the French Research Agency (ANR).
NASA Astrophysics Data System (ADS)
El Alem, A.
2016-12-01
Harmful algal bloom (HAB) causes negative impacts to other organisms by producing natural toxins, mechanical damage to other micro-organisms, or simply by degrading waters quality. Contaminated waters could expose several billions of population to serious intoxications problems. Traditionally, HAB monitoring is made with standard methods limited to a restricted network of sampling points. However, rapid evolution of HABs makes it difficult to monitor their variation in time and space, threating then public safety. Daily monitoring is then the best way to control and to mitigate their harmful effect upon population, particularly for sources feeding cities. Recently, an approach for estimating chlorophyll-a (Chl-a) concentration, as a proxy of HAB presence, in inland waters based MODIS imagery downscaled to 250 meters spatial resolution was developed. Statistical evaluation of the developed approach highlighted the accuracy of Chl-a estimate with a R2 = 0.98, a relative RMSE of 15%, a relative BIAS of -2%, and a relative NASH of 0.95. Temporal resolution of MODIS sensor allows then a daily monitoring of HAB spatial distribution for inland waters of more than 2.25 Km2 of surface. Groupe-Hemisphere, a company specialized in environmental and sustainable planning in Quebec, has shown a great interest to the developed approach. Given the complexity of the preprocessing (geometric and atmospheric corrections as well as downscaling spatial resolution) and processing (Chl-a estimate) of images, a standalone application under the MATLAB's GUI environment was developed. The application allows an automated process for all preprocessing and processing steps. Outputs produced by the application for end users, many of whom may be decision makers or policy makers in the public and private sectors, allows a near-real time monitoring of water quality for a more efficient management.
The psychology of drinking water quality: An exploratory study
NASA Astrophysics Data System (ADS)
Syme, Geoffrey J.; Williams, Katrina D.
1993-12-01
Perceptions of drinking water quality were measured for residents at four locations in Western Australia. The total dissolved solid levels for the locations varied. Four scales of drinking water satisfaction were measured: acceptability of water quality; water quality risk judgment; perception of neighborhood water quality; and attitudes toward fluoride as an additive. Responses to each of these scales did not appear to be highly related to total dissolved solids. The relationship between attitudes toward water quality and a variety of psychological, attitudinal, experiential, and demographic variables was investigated. It was found that responses to the acceptability of water quality and water quality risk judgment scales related to perceived credibility of societal institutions and feelings of control over water quality and environmental problems. For the remaining two scales few significant correlations were found. The results support those who advocate localized information and involvement campaigns on drinking water quality issues.
40 CFR 130.3 - Water quality standards.
Code of Federal Regulations, 2010 CFR
2010-07-01
... QUALITY PLANNING AND MANAGEMENT § 130.3 Water quality standards. A water quality standard (WQS) defines the water quality goals of a water body, or portion thereof, by designating the use or uses to be made... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Water quality standards. 130.3 Section...
A multi-disciplinary approach for sea water quality monitoring: the IOSMOS project
NASA Astrophysics Data System (ADS)
Lacava, Teodosio; Ciancia, Emanuele; Coviello, Irina; Daraio, Maria; Paciello, Rossana; Pergola, Nicola; Pignatti, Stefano; Santini, Federico; Tramutoli, Valerio; Vallianatos, Filippos
2013-04-01
Coastal zones are complex and dynamic ecosystems which represent one of the most productive areas of the marine environment. They are an important economic resource for human populations: they provide food, energy as well as a lot of commerce and recreation activities. The strong anthropization, the irrational exploitation of resources and the climate changes are causing a strong modification of the coastal areas, representing a continuous threat to the biodiversity of these areas. This is why coastal zones deserve the developing and implementing of a monitoring system able to guarantee their consistent and reliable control as well as to timely identify any sign of degradation. Water quality is an important indicator of the health of coastal ecosystem. Remote sensing data can give relevant information in this framework, offering the capability to provide the spatial distribution of water constituents over large spatial areas with high temporal rates and relatively low costs. In particular Ocean Color (OC) satellite instruments furnish information both on sea surface optical variables (e.g. upwelling normalized water-leaving radiances) and on bio-optical parameters such as chlorophyll-a (as a proxy of phytoplankton), suspended materials and dissolved organic matter. A study of these parameters and of their evolution in the space-time domain may provide useful information on the overall quality of the sea water for a specific area, offering, in addition the reference behaviors necessary for identifying significant changes (possibly induced by anthropogenic pressure) in the coastal environment. In this context main aim of IOSMOS (IOnian Sea water quality MOnitoring by Satellite data) - a Project for European Transnational Cooperation co financed by the Operational Programme ERDF Basilicata 2007-2013 - is the development of advanced and exportable satellite products for measuring the above mentioned coastal water parameters as well as to timely identify short-medium term changes potentially dangerous for environment and/or human health. Original techniques based on multi-temporal satellite data analyses will be developed and validated on the base of airborne and in situ calibration campaigns. Their advantages, in terms of reliability, sensitivity and exportability, will be evaluated also by comparison with existing satellite products achievable by EOS-MODIS, NPP-VIIRS and SeaWifs sensors. In this paper first IOSMOS project results will be presented and discussed, starting from the preliminary long-term (up to 15 years) analyses performed for the Ionian sea within the gulf of Taranto (Southern Italy) with particular attention to the area along Basilicata Region coasts.
Li, Qingguang; Wu, Pan; Zha, Xuefang; Li, Xuexian; Wu, Linna; Gu, Shangyi
2018-04-24
The generation of acid mine drainage (AMD) may accelerate watershed erosion and promote the migration of heavy metals, then threaten local ecosystems such as aquatic life and even human health. Previous studies have focused primarily on influence of AMD in surface environment. In order to reveal the acidizing processes in karst high-sulfur coalfield in Southwest China, this study, by contrast, focused on the hydrogeochemical evolution process and acidification mechanism of mine water in Zhijin coalfield, western Guizhou Province. The oxidation of pyrite and other sulfides induced strong acidification of mine water according to the water chemical analysis. As a result, a series of geochemical processes such as dissolution of carbonates and silicates, hydrolysis of metal ions, and degassing of CO 2 complicated water chemical evolution. The dissolution of silicates controlled the chemical composition of mine water, but more carbonates might be dissolved during the acidification of mine water. The sources of sulfate are quite different in water samples collected from the two selected mine. According to sulfur isotope analysis, the dissolution of gypsum is the primary source of sulfate in samples from Hongfa mine, whereas sulfide oxidation contributed a large amount of sulfate to the mine water in Fenghuangshan mine. The dissolution of carbonates should be an important source of DIC in mine water and CO 2 originating from organic mineralization might also have a certain contribution. This study elucidated the groundwater chemical evolution processes in high-sulfur coal-bearing strata and provided a foundation for further study of carbonates erosion and carbon emission during acidification of mine water.
Ochoo, Benjamin; Valcour, James; Sarkar, Atanu
2017-11-01
Studying public perception on drinking water quality is crucial for managing of water resources, generation of water quality standards, and surveillance of the drinking-water quality. However, in policy discourse, the reliability of public perception concerning drinking water quality and associated health risks is questionable. Does the public perception of water quality equate with the actual water quality? We investigated public perceptions of water quality and the perceived health risks and associated with the actual quality of public water supplies in the same communities. The study was conducted in 45 communities of Newfoundland (Canada) in 2012. First, a telephone survey of 100 households was conducted to examine public perceptions of drinking water quality of their respective public sources. Then we extracted public water quality reports of the same communities (1988-2011) from the provincial government's water resources portal. These reports contained the analysis of 2091 water samples, including levels of Disinfection By-Products (DBPs), nutrients, metals, ions and physical parameters. The reports showed that colour, manganese, total dissolved solids, iron, turbidity, and DBPs were the major detected parameters in the public water. However, the majority of the respondents (>56%) were either completely satisfied or very satisfied with the quality of drinking water. Older, higher educated and high-income group respondents were more satisfied with water quality than the younger, less educated and low-income group respondents. The study showed that there was no association with public satisfaction level and actual water quality of the respective communities. Even, in the communities, supplied by the same water system, the respondents had differences in opinion. Despite the effort by the provincial government to make the water-test results available on its website for years, the study showed existing disconnectedness between public perception of drinking water quality and actual quality. We had little scope to explore the possible explanations, and hence further studies are required to verify the age, gender educational status and income differential about the satisfaction of public service like water supply. Copyright © 2017 Elsevier Inc. All rights reserved.
40 CFR 131.35 - Colville Confederated Tribes Indian Reservation.
Code of Federal Regulations, 2013 CFR
2013-07-01
... PROGRAMS WATER QUALITY STANDARDS Federally Promulgated Water Quality Standards § 131.35 Colville Confederated Tribes Indian Reservation. The water quality standards applicable to the waters within the... these Federal water quality standards to prescribe minimum water quality requirements for the surface...
Ye, Bixiong; E, Xueli; Zhang, Lan
2015-01-01
To optimize non-regular drinking water quality indices (except Giardia and Cryptosporidium) of urban drinking water. Several methods including drinking water quality exceed the standard, the risk of exceeding standard, the frequency of detecting concentrations below the detection limit, water quality comprehensive index evaluation method, and attribute reduction algorithm of rough set theory were applied, redundancy factor of water quality indicators were eliminated, control factors that play a leading role in drinking water safety were found. Optimization results showed in 62 unconventional water quality monitoring indicators of urban drinking water, 42 water quality indicators could be optimized reduction by comprehensively evaluation combined with attribute reduction of rough set. Optimization of the water quality monitoring indicators and reduction of monitoring indicators and monitoring frequency could ensure the safety of drinking water quality while lowering monitoring costs and reducing monitoring pressure of the sanitation supervision departments.
Ng, Gene-Hua Crystal.; Bekins, Barbara A.; Cozzarelli, Isabelle M.; Baedecker, Mary Jo; Bennett, Philip C.; Amos, Richard T.; Herkelrath, William N.
2015-01-01
Anaerobic biodegradation of organic amendments and contaminants in aquifers can trigger secondary water quality impacts that impair groundwater resources. Reactive transport models help elucidate how diverse geochemical reactions control the spatiotemporal evolution of these impacts. Using extensive monitoring data from a crude oil spill site near Bemidji, Minnesota (USA), we implemented a comprehensive model that simulates secondary plumes of depleted dissolved O2 and elevated concentrations of Mn2+, Fe2+, CH4, and Ca2+ over a two-dimensional cross section for 30 years following the spill. The model produces observed changes by representing multiple oil constituents and coupled carbonate and hydroxide chemistry. The model includes reactions with carbonates and Fe and Mn mineral phases, outgassing of CH4 and CO2 gas phases, and sorption of Fe, Mn, and H+. Model results demonstrate that most of the carbon loss from the oil (70%) occurs through direct outgassing from the oil source zone, greatly limiting the amount of CH4 cycled down-gradient. The vast majority of reduced Fe is strongly attenuated on sediments, with most (91%) in the sorbed form in the model. Ferrous carbonates constitute a small fraction of the reduced Fe in simulations, but may be important for furthering the reduction of ferric oxides. The combined effect of concomitant redox reactions, sorption, and dissolved CO2 inputs from source-zone degradation successfully reproduced observed pH. The model demonstrates that secondary water quality impacts may depend strongly on organic carbon properties, and impacts may decrease due to sorption and direct outgassing from the source zone.
Ng, Gene-Hua Crystal; Bekins, Barbara A.; Cozzarelli, Isabelle M.; Baedecker, Mary Jo; Bennett, Philip C.; Amos, Richard T.
2014-01-01
Secondary water quality impacts can result from a broad range of coupled reactions triggered by primary groundwater contaminants. Data from a crude-oil spill research site near Bemidji, MN provide an ideal test case for investigating the complex interactions controlling secondary impacts, including depleted dissolved oxygen and elevated organic carbon, inorganic carbon, CH4, Mn, Fe, and other dissolved ions. To better understand these secondary impacts, this study began with an extensive data compilation of various data types, comprising aqueous, sediment, gas, and oil phases, covering a 260 m cross-sectional domain over 30 years. Mass balance calculations are used to quantify pathways that control secondary components, by using the data to constrain the sources and sinks for the important redox processes. The results show that oil constituents other than BTEX (benzene, toluene, ethylbenzene, o-, m- and p-xylenes), including n-alkanes and other aromatic compounds, play significant roles in plume evolution and secondary water quality impacts. The analysis underscores previous results on the importance of non-aqueous phases. Over 99.9% of the Fe2+ plume is attenuated by immobilization on sediments as Fe(II) and 85–95% of the carbon biodegradation products are outgassed. Gaps identified in carbon and Fe mass balances and in pH buffering mechanisms are used to formulate a new conceptual model. This new model includes direct out-gassing of CH4 and CO2 from organic carbon biodegradation, dissolution of directly produced CO2, and sorption with H+ exchange to improve pH buffering. The identification of these mechanisms extends understanding of natural attenuation of potential secondary impacts at enhanced reductive dechlorination sites, particularly for reduced Fe plumes, produced CH4, and pH perturbations.
NASA Astrophysics Data System (ADS)
Ng, G.-H. Crystal; Bekins, Barbara A.; Cozzarelli, Isabelle M.; Baedecker, Mary Jo; Bennett, Philip C.; Amos, Richard T.
2014-08-01
Secondary water quality impacts can result from a broad range of coupled reactions triggered by primary groundwater contaminants. Data from a crude-oil spill research site near Bemidji, MN provide an ideal test case for investigating the complex interactions controlling secondary impacts, including depleted dissolved oxygen and elevated organic carbon, inorganic carbon, CH4, Mn, Fe, and other dissolved ions. To better understand these secondary impacts, this study began with an extensive data compilation of various data types, comprising aqueous, sediment, gas, and oil phases, covering a 260 m cross-sectional domain over 30 years. Mass balance calculations are used to quantify pathways that control secondary components, by using the data to constrain the sources and sinks for the important redox processes. The results show that oil constituents other than BTEX (benzene, toluene, ethylbenzene, o-, m- and p-xylenes), including n-alkanes and other aromatic compounds, play significant roles in plume evolution and secondary water quality impacts. The analysis underscores previous results on the importance of non-aqueous phases. Over 99.9% of the Fe2 + plume is attenuated by immobilization on sediments as Fe(II) and 85-95% of the carbon biodegradation products are outgassed. Gaps identified in carbon and Fe mass balances and in pH buffering mechanisms are used to formulate a new conceptual model. This new model includes direct out-gassing of CH4 and CO2 from organic carbon biodegradation, dissolution of directly produced CO2, and sorption with H+ exchange to improve pH buffering. The identification of these mechanisms extends understanding of natural attenuation of potential secondary impacts at enhanced reductive dechlorination sites, particularly for reduced Fe plumes, produced CH4, and pH perturbations.
40 CFR 130.3 - Water quality standards.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 23 2012-07-01 2012-07-01 false Water quality standards. 130.3 Section 130.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.3 Water quality standards. A water quality standard (WQS) defines...
40 CFR 130.3 - Water quality standards.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 22 2014-07-01 2013-07-01 true Water quality standards. 130.3 Section 130.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.3 Water quality standards. A water quality standard (WQS) defines...
40 CFR 130.3 - Water quality standards.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 23 2013-07-01 2013-07-01 false Water quality standards. 130.3 Section 130.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.3 Water quality standards. A water quality standard (WQS) defines...
40 CFR 130.3 - Water quality standards.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 22 2011-07-01 2011-07-01 false Water quality standards. 130.3 Section 130.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.3 Water quality standards. A water quality standard (WQS) defines...
Conifer species adapt to low-rainfall climates by following one of two divergent pathways.
Brodribb, Timothy J; McAdam, Scott A M; Jordan, Gregory J; Martins, Samuel C V
2014-10-07
Water stress is one of the primary selective forces in plant evolution. There are characters often cited as adaptations to water stress, but links between the function of these traits and adaptation to drying climates are tenuous. Here we combine distributional, climatic, and physiological evidence from 42 species of conifers to show that the evolution of drought resistance follows two distinct pathways, both involving the coordinated evolution of tissues regulating water supply (xylem) and water loss (stomatal pores) in leaves. Only species with very efficient stomatal closure, and hence low minimum rates of water loss, inhabit dry habitats, but species diverged in their apparent mechanism for maintaining closed stomata during drought. An ancestral mechanism found in Pinaceae and Araucariaceae species relies on high levels of the hormone abscisic acid (ABA) to close stomata during water stress. A second mechanism, found in the majority of Cupressaceae species, uses leaf desiccation rather than high ABA levels to close stomata during sustained water stress. Species in the latter group were characterized by xylem tissues with extreme resistance to embolism but low levels of foliar ABA after 30 d without water. The combination of low levels of ABA under stress with cavitation-resistant xylem enables these species to prolong stomatal opening during drought, potentially extending their photosynthetic activity between rainfall events. Our data demonstrate a surprising simplicity in the way conifers evolved to cope with water shortage, indicating a critical interaction between xylem and stomatal tissues during the process of evolution to dry climates.
Water Quality of Hills Water, Supply Water and RO Water Machine at Ulu Yam Selangor
NASA Astrophysics Data System (ADS)
Ngadiman, N.; ‘I Bahari, N.; Kaamin, M.; Hamid, N. B.; Mokhtar, M.; Sahat, S.
2016-07-01
The rapid development resulted in the deterioration of the quality of drinking water in Malaysia. Recognizing the importance of water quality, new alternatives for drinking water such as mineral water processing from reverse osmosis (RO) machine become more popular. Hence, the demand for mineral water, natural spring water or water from the hills or mountains rose lately. More consumers believed the quality of these spring water better than other source of drinking water. However, the quality of all the drinking water sources is to meet the required quality standard. Therefore, this paper aims to measure the quality of the waters from hills, from RO machine and the water supply in Ulu Yam, Selangor Batang Kali, Malaysia. The water quality was determined based on following parameters: ammoniacal nitrogen (NH3), iron (Fe), turbidity (NTU) and pH. The results show that the water from hills has better quality compared to water supply and water from RO machine. The value of NH3 ranged from 0.03 mg/L- 0.67 mg/L; Fe was from 0.03mg/L - 0.12 mg/L, turbidity at 0.42 NTU - 0.88 NTU and pH is at 6.60 - 0.71. Based on the studied parameters, all three types of water are fit for drinking and have met the required national drinking water quality standard.
Evaluating benefits and costs of changes in water quality.
Jessica Koteen; Susan J. Alexander; John B. Loomis
2002-01-01
Water quality affects a variety of uses, such as municipal water consumption and recreation. Changes in water quality can influence the benefits water users receive. The problem is how to define water quality for specific uses. It is not possible to come up with one formal definition of water quality that fits all water uses. There are many parameters that influence...
Code of Federal Regulations, 2010 CFR
2010-04-01
... water quality management and control. However, protection of the water resources of the basin from... quality program in the comprehensive plan. (c) The Commission's role in water quality management and... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Water quality. 801.7...
40 CFR 130.6 - Water quality management plans.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 23 2012-07-01 2012-07-01 false Water quality management plans. 130.6 Section 130.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.6 Water quality management plans. (a) Water quality management (WQM...
40 CFR 130.6 - Water quality management plans.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 23 2013-07-01 2013-07-01 false Water quality management plans. 130.6 Section 130.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.6 Water quality management plans. (a) Water quality management (WQM...
40 CFR 130.6 - Water quality management plans.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 22 2014-07-01 2013-07-01 true Water quality management plans. 130.6 Section 130.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.6 Water quality management plans. (a) Water quality management (WQM...
Environmental politics in the 1990s: The tension between liberalism and environmental quality
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cahn, M.A.
1991-01-01
There are two structural tensions between liberalism and environmental quality. First, liberalism's emphasis on individual self-interest creates a problematic concept of communal good. Society, as manifest in liberal contract theory, exists not to find some higher good, but to protect individual rights. Individual and corporate property rights have consistently overshadowed community claims on resource management. Second, capitalism has been characterized by a constant drive for expansion in search of increased productivity and profit. The impact of that expansionary ethic has been overuse of limited resources and the poisoning of the physical environment. This study combines normative theory with case studiesmore » of the substantive policy areas of air, water, and waste. Environmental policy's analyzed with attention to the parameters of American political culture and the inherent limitations the language of liberalism places on policy choices. The literature on symbolic policy is then applied exploring the role of symbolic politics in easing the tension between liberalism and environmental quality. Ultimately, substantive policy areas are explored in a effort to explain the evolution of specific policies.« less
ERIC Educational Resources Information Center
Yu, Shu-Mey; Yore, Larry D.
2013-01-01
The purpose of this study was to investigate the quality, evolution, and position of university students' argumentation about organic agriculture over a 4-week argument-critique-argument e-learning experience embedded in a first year university biology course. The participants (N = 43) were classified into three groups based on their…
40 CFR 130.6 - Water quality management plans.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Water quality management plans. 130.6... QUALITY PLANNING AND MANAGEMENT § 130.6 Water quality management plans. (a) Water quality management (WQM... and certified and approved updates to those plans. Continuing water quality planning shall be based...
40 CFR 130.6 - Water quality management plans.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 22 2011-07-01 2011-07-01 false Water quality management plans. 130.6... QUALITY PLANNING AND MANAGEMENT § 130.6 Water quality management plans. (a) Water quality management (WQM... when they are needed to address water quality problems. (1) Total maximum daily loads. TMDLs in...
Brine evolution and mineral deposition in hydrologically open evaporite basins
Sanford, W.E.; Wood, W.W.
1991-01-01
A lumped-parameter, solute mass-balance model is developed to define the role of water outflow from a well-mixed basin. A mass-balance model is analyzed with a geochemical model designed for waters with high ionic strengths. Two typical waters, seawater and a Na-HCO3 ground water, are analyzed to illustrate the control that the leakage ratio (or hydrologic openness of the basin) has on brine evolution and the suite and thicknesses of evaporite minerals deposited. The analysis suggests that brines evolve differently under different leakage conditions. -from Authors
Chen, Xiang; Zhou, Weiqi; Pickett, Steward T. A.; Li, Weifeng; Han, Lijian
2016-01-01
Rapid urbanization with intense land use and land cover (LULC) change and explosive population growth has a great impact on water quality. The relationship between LULC characteristics and water quality provides important information for non-point sources (NPS) pollution management. In this study, we first quantified the spatial-temporal patterns of five water quality variables in four watersheds with different levels of urbanization in Beijing, China. We then examined the effects of LULC on water quality across different scales, using Pearson correlation analysis, redundancy analysis, and multiple regressions. The results showed that water quality was improved over the sampled years but with no significant difference (p > 0.05). However, water quality was significantly different among nonurban and both exurban and urban sites (p < 0.05). Forest land was positively correlated with water quality and affected water quality significantly (p < 0.05) within a 200 m buffer zone. Impervious surfaces, water, and crop land were negatively correlated with water quality. Crop land and impervious surfaces, however, affected water quality significantly (p < 0.05) for buffer sizes greater than 800 m. Grass land had different effects on water quality with the scales. The results provide important insights into the relationship between LULC and water quality, and thus for controlling NPS pollution in urban areas. PMID:27128934
Rasmussen, Teresa J.; Bennett, Trudy J.; Foster, Guy M.; Graham, Jennifer L.; Putnam, James E.
2014-01-01
As the Nation’s largest water, earth, and biological science and civilian mapping information agency, the U.S. Geological Survey is relied on to collect high-quality data, and produce factual and impartial interpretive reports. This quality-assurance and data-management plan provides guidance for water-quality activities conducted by the Kansas Water Science Center. Policies and procedures are documented for activities related to planning, collecting, storing, documenting, tracking, verifying, approving, archiving, and disseminating water-quality data. The policies and procedures described in this plan complement quality-assurance plans for continuous water-quality monitoring, surface-water, and groundwater activities in Kansas.
40 CFR 131.21 - EPA review and approval of water quality standards.
Code of Federal Regulations, 2010 CFR
2010-07-01
... (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Procedures for Review and Revision of Water Quality Standards § 131.21 EPA review and approval of water quality standards. (a) After the State submits its... analysis. (b) The Regional Administrator's approval or disapproval of a State water quality standard shall...
Relationship between Hydrodynamic Conditions and Water Quality in Landscape Water Body
NASA Astrophysics Data System (ADS)
Kang, Mengxin; Tian, Yimei; Zhang, Haiya; Wang, Dehong
2018-01-01
The urban landscape water usually lacks necessary water cycle and water speed is closed to zero, which easily lead to eutrophication in water system and deterioration of water quality. Therefore, understanding the impact of water circulation on the water quality is of great significance. With that significance, this research has been done to investigate the relationship between hydrodynamic conditions and water quality of urban landscape water based on adopted water quality indexes such as chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP) and nitrogen-ammonia (NH3-N). Moreover, MIKE 21 model is used to simulate the hydrodynamics and water quality under different cases in an urban landscape lake. The results of simulation show that water circulation system could effectively improve current speeds, reduce the proportion of stagnation area, and solve the problem of water quality deterioration caused by reclaimed water in the lake.
Water quality . . . potential sources of pollution
Vandas, Stephen; Farrar, Frank
1996-01-01
What is water quality? To most students, water quality may suggest only "clean" water for drinking, swimming, and fishing. But to the farmer or manufacturer, water quality may have an entirely different meaning. One of the most important issues concerning the quality of water is how that water will be used. Water that is perfectly fine for irrigation might not be suitable for drinking or swimming.
In 1990, Managing Troubled Waters concluded by stating three primary conclusions and then developing specific recommendations regarding their execution. Using the decade of the 90s, we examine the evolution of the U.S. EPA's Environmental Monitoring and Assessment Program's Coast...
An innovative index for evaluating water quality in streams.
Said, Ahmend; Stevens, David K; Sehlke, Gerald
2004-09-01
A water quality index expressed as a single number is developed to describe overall water quality conditions using multiple water quality variables. The index consists of water quality variables: dissolved oxygen, specific conductivity, turbidity, total phosphorus, and fecal coliform. The objectives of this study were to describe the preexisting indices and to define a new water quality index that has advantages over these indices. The new index was applied to the Big Lost River Watershed in Idaho, and the results gave a quantitative picture for the water quality situation. If the new water quality index for the impaired water is less than a certain number, remediation-likely in the form of total maximum daily loads or changing the management practices-may be needed. The index can be used to assess water quality for general beneficial uses. Nevertheless, the index cannot be used in making regulatory decisions, indicate water quality for specific beneficial uses, or indicate contamination from trace metals, organic contaminants, and toxic substances.
Life on Mars? II. Physical restrictions
NASA Technical Reports Server (NTRS)
Mancinelli, R. L.; Banin, A.
1995-01-01
The primary physical factors important to life's evolution on a planet include its temperature, pressure and radiation regimes. Temperature and pressure regulate the presence and duration of liquid water on the surface of Mars. The prolonged presence of liquid water is essential for the evolution and sustained presence of life on a planet. It has been postulated that Mars has always been a cold dry planet; it has also been postulated that early mars possessed a dense atmosphere of CO2 (> or = 1 bar) and sufficient water to cut large channels across its surface. The degree to which either of these postulates is true correlates with the suitability of Mars for life's evolution. Although radiation can destroy living systems, the high fluxes of UV radiation on the martian surface do not necessarily stop the origin and early evolution of life. The probability for life to have arisen and evolved to a significant degree on Mars, based on the postulated ranges of early martian physical factors, is almost solely related to the probability of liquid water existing on the planet for at least hundreds of millions to billions of years.
Water-quality assessment of the Smith River drainage basin, California and Oregon
Iwatsubo, Rick T.; Washabaugh, Donna S.
1982-01-01
A water-quality assessment of the Smith River drainage basin was made to provide a summary of the water-quality conditions including known or potential water-quality problems. Results of the study showed that the water quality of the Smith River is excellent and generally meets the water-quality objectives for the beneficial uses identified by the California Regional Water Quality Control Board, North Coast Region. Known and potential problems related to water quality include: Sedimentation resulting from both natural erosional processes and land-use activities such as timber harvest, road construction, and mining that accelerate the erosional processes; bacterial contamination of surface and ground waters from inundated septic tanks and drainfields, and grazing activities; industrial spills which have resulted in fish kills and oil residues; high concetrations of iron in ground water; log and debris jams creating fish migration barriers; and pesticide and trace-element contamination from timber-harvest and mining activities, respectively. Future studies are needed to establish: (1) a sustained long-term monitoring program to provide a broad coverage of water-quality conditions in order to define long-term water-quality trends; and (2) interpretive studies to determine the source of known and potential water-quality problems. (USGS)
3D mapping and simulation of Geneva Lake environmental data
NASA Astrophysics Data System (ADS)
Villard, Roch; Maignan, Michel; Kanevski, Mikhail; Rapin, Francois; Klein, Audrey
2010-05-01
The Geneva Lake is the biggest alpine and subalpine lake in central Europe. The depth of this lake is 309 meters and its total volume of water is 89 billions m3. It takes, on average, around twelve years so that waters of the lake are completely brewed. Furthermore the Geneva lake waters are rich in dissolved substances as carbonate, sulfate. The quantity of particles in suspension in the lake, which mainly arrived from the Rhône, is nowadays around height million of tones. The International Commission for the Leman Lake (CIPEL) works about the improvement of the quality of this lake since 1962. In the present study three dimensional environmental data (temperature, oxygen and nitrate) which cover the period from 1954 to 2008, for a total of 27'500 cases are investigated. We are interested to study the evolution of the temperature of the lake because there is an impact on the reproduction of fishes and also because the winter brewing of the water makes the re-oxygenation of deep-water. In order that biological balance is maintained in a lake, there must be enough oxygen in the water. Moreover, we work on nitrate distribution and evolution because contributions in fertilizers cause eutrophication of lake. The data are very numerous when we consider the time series, some of them with more than 300 occurrences, but there are between 2 and 15 data available for spatial cartography. The basic methodology used for the analysis, mapping and simulations of 3D patterns of environmental data is based on geostatistical predictions (family of kriging models) and conditional stochastic simulations. Spatial and temporal variability, 3D monitoring networks changing over time, make this study challenging. An important problem is also to make interpolation/simulations over a long period of time, like ten years. One way used to overcome this problem, consists in using a weighted average of ten variograms during this period. 3D mapping was carried out using environment data for several depths. Applying all data comprehensive analysis both in space and in time was performed. The evolution of the distribution of environmental parameters and their difference in space between two periods and also several times series were studied. Furthermore with the analysis of temporal measurements depending on spatial coordinates (x, y, z) the trends, periodicity, and seasonal variation or cycles were evaluated. First results demonstrate no global warming in such environment. However certain currents and their evolution in the lake were identified. Then, we can see the movement of cold and hot waters in the lake during time and in space. A main question posed by ecologists is: is there any global warming of the lake? According to the results based on date 1954-1980, no global warming either of the "Small Lake" (Geneva) or the whole lake was put into evidence. However the temperatures of the different parts of the lake vary from one year to another year with significant differences of warming, respectively cooling of different areas and at different depths. The graphical representations of time series of temperature at one location for different depths show clearly the annual rhythm and also other frequencies (11 years). The historical well known "cold years" are well identified. At some years, one can observe an inversion of temperature when the cold water in the depth comes upwards to the surface. Spatial patterns are also found for the nitrate content in water. The future developments deal with multivariate analysis and simulations of environmental and pollution data in the lake.
Water quality assessment and meta model development in Melen watershed - Turkey.
Erturk, Ali; Gurel, Melike; Ekdal, Alpaslan; Tavsan, Cigdem; Ugurluoglu, Aysegul; Seker, Dursun Zafer; Tanik, Aysegul; Ozturk, Izzet
2010-07-01
Istanbul, being one of the highly populated metropolitan areas of the world, has been facing water scarcity since the past decade. Water transfer from Melen Watershed was considered as the most feasible option to supply water to Istanbul due to its high water potential and relatively less degraded water quality. This study consists of two parts. In the first part, water quality data covering 26 parameters from 5 monitoring stations were analyzed and assessed due to the requirements of the "Quality Required of Surface Water Intended for the Abstraction of Drinking Water" regulation. In the second part, a one-dimensional stream water quality model with simple water quality kinetics was developed. It formed a basic design for more advanced water quality models for the watershed. The reason for assessing the water quality data and developing a model was to provide information for decision making on preliminary actions to prevent any further deterioration of existing water quality. According to the water quality assessment at the water abstraction point, Melen River has relatively poor water quality with regard to NH(4)(+), BOD(5), faecal streptococcus, manganese and phenol parameters, and is unsuitable for drinking water abstraction in terms of COD, PO(4)(3-), total coliform, total suspended solids, mercury and total chromium parameters. The results derived from the model were found to be consistent with the water quality assessment. It also showed that relatively high inorganic nitrogen and phosphorus concentrations along the streams are related to diffuse nutrient loads that should be managed together with municipal and industrial wastewaters. Copyright 2010 Elsevier Ltd. All rights reserved.
Rao, N Subba; Rao, P Surya; Reddy, G Venktram; Nagamani, M; Vidyasagar, G; Satyanarayana, N L V V
2012-08-01
Study on chemical characteristics of groundwater and impacts of groundwater quality on human health, plant growth, and industrial sector is essential to control and improve the water quality in every part of the country. The area of the Varaha River Basin is chosen for the present study, where the Precambrian Eastern Ghats underlain the Recent sediments. Groundwater quality is of mostly brackish and very hard, caused by the sources of geogenic, anthropogenic, and marine origin. The resulting groundwater is characterized by Na(+) > Mg(2+) > Ca(2+) : [Formula: see text] > Cl(-) > [Formula: see text], Na(+) > Mg(2+) > Ca(2+) : [Formula: see text] > Cl(-) > [Formula: see text] > [Formula: see text], Na(+) > Mg(2+) > Ca(2+) : [Formula: see text] > Cl(-), and Na(+) > Mg(2+) > Ca(2+) : Cl(-) > [Formula: see text] > [Formula: see text] facies, following the topographical and water flow-path conditions. The genetic geochemical evolution of groundwater ([Formula: see text] and Cl(-)-[Formula: see text] types under major group of [Formula: see text]) and the hydrogeochemical signatures (Na(+)/Cl(-), >1 and [Formula: see text]/Cl(-), <1) indicate that the groundwater is of originally fresh quality, but is subsequently modified to brackish by the influences of anthropogenic and marine sources, which also supported by the statistical analysis. The concentrations of total dissolved solids (TDS), TH, Mg(2+), Na(+), K(+), [Formula: see text], Cl(-), [Formula: see text], and F(-) are above the recommended limits prescribed for drinking water in many locations. The quality of groundwater is of mostly moderate in comparison with the salinity hazard versus sodium hazard, the total salt concentration versus percent sodium, the residual sodium carbonate, and the magnesium hazard, but is of mostly suitable with respect to the permeability index for irrigation. The higher concentrations of TDS, TH, [Formula: see text], Cl(-), and [Formula: see text] in the groundwater cause the undesirable effects of incrustation and corrosion in many locations. Appropriate management measures are, therefore, suggested to improve the groundwater quality.
Hydrogen storage and evolution catalysed by metal hydride complexes.
Fukuzumi, Shunichi; Suenobu, Tomoyoshi
2013-01-07
The storage and evolution of hydrogen are catalysed by appropriate metal hydride complexes. Hydrogenation of carbon dioxide by hydrogen is catalysed by a [C,N] cyclometalated organoiridium complex, [Ir(III)(Cp*)(4-(1H-pyrazol-1-yl-κN(2))benzoic acid-κC(3))(OH(2))](2)SO(4) [Ir-OH(2)](2)SO(4), under atmospheric pressure of H(2) and CO(2) in weakly basic water (pH 7.5) at room temperature. The reverse reaction, i.e., hydrogen evolution from formate, is also catalysed by [Ir-OH(2)](+) in acidic water (pH 2.8) at room temperature. Thus, interconversion between hydrogen and formic acid in water at ambient temperature and pressure has been achieved by using [Ir-OH(2)](+) as an efficient catalyst in both directions depending on pH. The Ir complex [Ir-OH(2)](+) also catalyses regioselective hydrogenation of the oxidised form of β-nicotinamide adenine dinucleotide (NAD(+)) to produce the 1,4-reduced form (NADH) under atmospheric pressure of H(2) at room temperature in weakly basic water. In weakly acidic water, the complex [Ir-OH(2)](+) also catalyses the reverse reaction, i.e., hydrogen evolution from NADH to produce NAD(+) at room temperature. Thus, interconversion between NADH (and H(+)) and NAD(+) (and H(2)) has also been achieved by using [Ir-OH(2)](+) as an efficient catalyst and by changing pH. The iridium hydride complex formed by the reduction of [Ir-OH(2)](+) by H(2) and NADH is responsible for the hydrogen evolution. Photoirradiation (λ > 330 nm) of an aqueous solution of the Ir-hydride complex produced by the reduction of [Ir-OH(2)](+) with alcohols resulted in the quantitative conversion to a unique [C,C] cyclometalated Ir-hydride complex, which can catalyse hydrogen evolution from alcohols in a basic aqueous solution (pH 11.9). The catalytic mechanisms of the hydrogen storage and evolution are discussed by focusing on the reactivity of Ir-hydride complexes.
Vining, Kevin C.; Cates, Steven W.
2006-01-01
Available surface-water quality, ground-water quality, and water-withdrawal data for the Spirit Lake Reservation were summarized. The data were collected intermittently from 1948 through 2004 and were compiled from U.S. Geological Survey databases, North Dakota State Water Commission databases, and Spirit Lake Nation tribal agencies. Although the quality of surface water on the reservation generally is satisfactory, no surface-water sources are used for consumable water supplies. Ground water on the reservation is of sufficient quality for most uses. The Tokio and Warwick aquifers have better overall water quality than the Spiritwood aquifer. Water from the Spiritwood aquifer is used mostly for irrigation. The Warwick aquifer provides most of the consumable water for the reservation and for the city of Devils Lake. Annual water withdrawals from the Warwick aquifer by the Spirit Lake Nation ranged from 71 million gallons to 122 million gallons during 2000-04.
Water quality evaluation of Al-Gharraf river by two water quality indices
NASA Astrophysics Data System (ADS)
Ewaid, Salam Hussein
2017-11-01
Water quality of Al-Gharraf river, the largest branch of Tigris River south of Iraq, was evaluated by the National Sanitation Foundation Water Quality Index (NFS WQI) and the Heavy Metal Pollution Index (HPI) depending on 13 physical, chemical, and biological parameters of water quality measured monthly at ten stations on the river during 2015. The NSF-WQI range obtained for the sampling sites was 61-70 indicating a medium water quality. The HPI value was 98.6 slightly below the critical value for drinking water of 100, and the water quality in the upstream stations is better than downstream due to decrease in water and the accumulation of contaminants along the river. This study explains the significance of applying the water quality indices that show the aggregate impact of ecological factors in charge of water pollution of surface water and which permits translation of the monitoring data to assist the decision makers.
Photo-catalysis water splitting by platinum-loaded zeolite A
NASA Astrophysics Data System (ADS)
Cheng, Jing; Gao, Changda; Jing, Ming; Lu, Jian; Lin, Hui; Han, Zhaoxia; Ni, Zhengji; Zhang, Dawei
2018-05-01
Under the λ≥420 nm visible light illumination, the Pt4+ ions exchanged LTA zeolite powders without further heat-treatment presented H2 evolution at a rate of 5 μl/(15 mg·h) via photocatalysis water splitting. It was shown that the efficiency of H2 generation by the Pt4+ exchanged LTA zeolite powders without further heat-treatment was higher than the counterpart of the samples with heat treatment. In addition, the samples with lower Pt loading concentration showed higher H2 evolution rate than those of higher Pt loading did. The higher H2 evolution efficiency can be attributed to the effective isolation of water molecules and Pt at the atomic or the few atom ‘cluster’ scale by LTA zeolite’s periodical porous structure, which ensures a more efficient electron transfer efficiency for H2 evolution. However, after extra heat treatment, the Pt atoms reduced from Pt4+ in LTA zeolite’s cavities may tend to migrate to the surface and then form nano-particles, which led to the lower H2 evolution efficiency.
NASA Astrophysics Data System (ADS)
Shi, Kun; Zhang, Yunlin; Zhu, Guangwei; Qin, Boqiang; Pan, Delu
2018-06-01
Water clarity (Secchi disk depth: SDD), as a proxy of water transparency, provides important information on the light availability to the water or lake ecosystem. Shallow lakes have been experienced dramatic environmental and climatic change. This study demonstrated using combination of long-term MODIS and in-situ measurements to track the dynamics of SDD with these environmental and climate changes in shallow water environments. We selected a typical turbid shallow Lake Taihu as our case study. Based on MODIS-Aqua data, an empirical model for estimating SDD was developed and validated. Subsequently, we employed the proposed model to derive the spatial and temporal SDD distribution patterns of Lake Taihu from 2003 to 2015. Combining MODIS-derived SDD time series of 2003-2015 and long-term in-situ SDD observations dated back to 1993, we elucidated SDD long-term variation trends and driving mechanism. Deteriorating water clarity from the long-term SDD observations indicated that Lake Taihu became more and more turbid and water quality was decreasing. Increasing in cyanobacterial bloom area, as a result of decreasing in wind speed and eutrophication, may partially be responsible for the decreasing trend. A predicted future decrease in the wind speed in Lake Taihu region could enhance the formation of cyanobacterial blooms and consequently lead to a further decrease in water clarity. This study suggested that coupling remote sensing monitoring and long-term in-situ observations could provide robust evidence and new insights to elucidate long-term dynamics in aquatic ecosystem evolution.
NASA Astrophysics Data System (ADS)
Liu, Ye; Tian, Fuqiang; Hu, Heping; Liu, Dengfeng; Sivapalan, Murugesu
2013-04-01
Socio-hydrology studies the co-evolution of coupled human-water systems, which is of great importance for long-term sustainable water resource management in basins suffering from serious eco-environmental degradation. Process socio-hydrology can benefit from the exploring the patterns of historical co-evolution of coupled human-water systems as a way to discovering the organizing principles that may underpin their co-evolution. As a self-organized entity, the human-water system in a river basin would evolve into certain steady states over a sufficiently long time but then could also experience sudden shifts due to internal or external disturbances that exceed system thresholds. In this study, we discuss three steady states (also called stages in the social sciences, including natural, human exploitation and recovery stages) and transitions between these during the past 1500 years in the Tarim River Basin of Western China, which a rich history of civilization including its place in the famous Silk Road that connected China to Europe. Specifically, during the natural stage with a sound environment that existed before the 19th century, shifts in the ecohydrological regime were mainly caused by environmental changes such river channel migration and climate change. During the human exploitation stages in the 5th and again in the 19th-20th centuries, however, humans gradually became the main drivers for system evolution, during which the basin experienced rapid population growth, fast socio-economic development and intense human activities. By the 1970s, after 200 years of colonization, the Tarim River Basin evolved into a new regime with vulnerable ecosystem and water system, and suffered from serious water shortages and desertification. Human society then began to take a critical look into the effects of their activities and reappraise the impact of human development on the ecohydrological system, which eventually led the basin into a treatment and recovery stage. Since then, the basin has shown a reverse trend of regime shift towards healing of the environmental damage that was inflicted in the previous stage of human development. In this paper we analyze the recasting effect of human activities on the water system and provide explanations on how human activities influence the co-evolution of human-water system from a broader perspective.
Comprehensive Flood Plain Studies Using Spatial Data Management Techniques.
1978-06-01
Hydrologic Engineer- ing Center computer programs that forecast urban storm water quality and dynamic in- stream water quality response to waste...determination. Water Quality The water quality analysis planned for the pilot study includes urban storm water quality forecasting and in-streamn...analysis is performed under the direction of Tony Thomas. Chief, Research Branch, by Jess Abbott for storm water quality analysis, R. G. Willey for
40 CFR 131.22 - EPA promulgation of water quality standards.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 21 2010-07-01 2010-07-01 false EPA promulgation of water quality standards. 131.22 Section 131.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Procedures for Review and Revision of Water Quality Standards § 131.22 EPA promulgation of water quality...
40 CFR 131.22 - EPA promulgation of water quality standards.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 22 2011-07-01 2011-07-01 false EPA promulgation of water quality standards. 131.22 Section 131.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Procedures for Review and Revision of Water Quality Standards § 131.22 EPA promulgation of water quality...
Ragsdale, R.; Vowinkel, E.; Porter, D.; Hamilton, P.; Morrison, R.; Kohut, J.; Connell, B.; Kelsey, H.; Trowbridge, P.
2011-01-01
The Integrated Ocean Observing System (IOOS??) Regional Associations and Interagency Partners hosted a water quality workshop in January 2010 to discuss issues of nutrient enrichment and dissolved oxygen depletion (hypoxia), harmful algal blooms (HABs), and beach water quality. In 2007, the National Water Quality Monitoring Council piloted demonstration projects as part of the National Water Quality Monitoring Network (Network) for U.S. Coastal Waters and their Tributaries in three IOOS Regional Associations, and these projects are ongoing. Examples of integrated science-based solutions to water quality issues of major concern from the IOOS regions and Network demonstration projects are explored in this article. These examples illustrate instances where management decisions have benefited from decision-support tools that make use of interoperable data. Gaps, challenges, and outcomes are identified, and a proposal is made for future work toward a multiregional water quality project for beach water quality.
Ragsdale, Rob; Vowinkel, Eric; Porter, Dwayne; Hamilton, Pixie; Morrison, Ru; Kohut, Josh; Connell, Bob; Kelsey, Heath; Trowbridge, Phil
2011-01-01
The Integrated Ocean Observing System (IOOS®) Regional Associations and Interagency Partners hosted a water quality workshop in January 2010 to discuss issues of nutrient enrichment and dissolved oxygen depletion (hypoxia), harmful algal blooms (HABs), and beach water quality. In 2007, the National Water Quality Monitoring Council piloted demonstration projects as part of the National Water Quality Monitoring Network (Network) for U.S. Coastal Waters and their Tributaries in three IOOS Regional Associations, and these projects are ongoing. Examples of integrated science-based solutions to water quality issues of major concern from the IOOS regions and Network demonstration projects are explored in this article. These examples illustrate instances where management decisions have benefited from decision-support tools that make use of interoperable data. Gaps, challenges, and outcomes are identified, and a proposal is made for future work toward a multiregional water quality project for beach water quality.
The geochemical evolution of riparian ground water in a forested piedmont catchment
Burns, Douglas A.; Plummer, Niel; McDonnell, Jeffrey J.; Busenberg, Eurybiades; Casile, Gerolamo C.; Kendall, Carol; Hooper, Richard P.; Freer, James E.; Peters, Norman E.; Beven, Keith; Schlosser, Peter
2003-01-01
The principal weathering reactions and their rates in riparian ground water were determined at the Panola Mountain Research Watershed (PMRW) near Atlanta, Georgia. Concentrations of major solutes were measured in ground water samples from 19 shallow wells completed in the riparian (saprolite) aquifer and in one borehole completed in granite, and the apparent age of each sample was calculated from chloroflourocarbons and tritium/helium-3 data. Concentrations of SiO2, Na+, and Ca2+ generally increased downvalley and were highest in the borehole near the watershed outlet. Strong positive correlations were found between the concentrations of these solutes and the apparent age of ground water that was modern (zero to one year) in the headwaters, six to seven years midway down the valley, and 26 to 27 years in the borehole, located ∼500 m downstream from the headwaters. Mass-balance modeling of chemical evolution showed that the downstream changes in ground water chemistry could be largely explained by weathering of plagioclase to kaolinite, with possible contributions from weathering of K-feldspar, biotite, hornblende, and calcite. The in situ rates of weathering reactions were estimated by combining the ground water age dates with geochemical mass-balance modeling results. The weathering rate was highest for plagioclase (∼6.4 μmol/L/year), but could not be easily compared with most other published results for feldspar weathering at PMRW and elsewhere because the mineral-surface area to which ground water was exposed during geochemical evolution could not be estimated. However, a preliminary estimate of the mineral-surface area that would have contacted the ground water to provide the observed solute concentrations suggests that the plagioclase weathering rate calculated in this study is similar to the rate calculated in a previous study at PMRW, and three to four orders of magnitude slower than those published in previous laboratory studies of feldspar weathering. An accurate model of the geochemical evolution of riparian ground water is necessary to accurately model the geochemical evolution of stream water at PMRW.
Leveraging Research Partnerships to Co-Produce Actionable Science and Build Institutional Capacity
NASA Astrophysics Data System (ADS)
Fleming, P.; Chinn, A.; Rufo Hill, J.; Edgerly, J.; Garcia, E.
2017-12-01
Seattle Public Utilities (SPU) provides high quality drinking water to 1.4 million people in the greater Seattle area and storm, wastewater and solid waste services to the City of Seattle. SPU's engagement on climate change has evolved significantly over the past 20 years. What began in 1997 as an inquiry into how El Nino may affect water supply has evolved into a broad based ongoing exploration that includes extensive in-house knowledge, capacity and expertise. This presentation will describe SPU's evolution from a funder and consumer of climate research to an active contributor to the development of applied research products, highlighted SPU's changing role in three climate impacts assessment studies. It will describe how SPU has leveraged these studies and partnerships to enhance its knowledge base, build its internal institutional capacity and produce actionable science that it is helping to foster incorporation of climate change into various aspects of utility planning and decision making. It will describe the PUMA Project and how the results from that research effort are being factored into SPU's state mandated Water System Plan.
Lumb, Ashok; Halliwell, Doug; Sharma, Tribeni
2006-02-01
All six ecosystem initiatives evolved from many years of federal, provincial, First Nation, local government and community attention to the stresses on sensitive habitats and species, air and water quality, and the consequent threats to community livability. This paper assesses water quality aspect for the ecosystem initiatives and employs newly developed Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) which provides a convenient mean of summarizing complex water quality data that can be easily understood by the public, water distributors, planners, managers and policy makers. The CCME WQI incorporates three elements: Scope - the number of water quality parameters (variables) not meeting water quality objectives (F(1)); Frequency - the number of times the objectives are not met (F(2)); and Amplitude. the extent to which the objectives are not met (F(3)). The index produces a number between 0 (worst) to 100 (best) to reflect the water quality. This study evaluates water quality of the Mackenzie - Great Bear sub-basin by employing two modes of objective functions (threshold values): one based on the CCME water quality guidelines and the other based on site-specific values that were determined by the statistical analysis of the historical data base. Results suggest that the water quality of the Mackenzie-Great Bear sub-basin is impacted by high turbidity and total (mostly particulate) trace metals due to high suspended sediment loads during the open water season. Comments are also provided on water quality and human health issues in the Mackenzie basin based on the findings and the usefulness of CCME water quality guidelines and site specific values.
Fulazzaky, Mohamad Ali
2010-09-01
Water quality degradation in the Citarum river will increase from the year to year due to increasing pollutant loads when released particularly from Bandung region of the upstream areas into the river without treatment. This will be facing the problems on water quality status to use for multi-purposes in the downstream areas. The water quality evaluation system is used to evaluate the available water condition that distinguishes into two categories, i.e., the water quality index (WQI) and water quality aptitude (WQA). The assessment of water quality for the Citarum river from 10 selected stations was found that the WQI situates in the bad category generally and the WQA ranges from the suitable quality for agriculture and livestock watering uses to the unsuitable for biological potential function, drinking water production, and leisure activities and sports in the upstream areas of Saguling dam generally.
Preface to volume 1: status and trends of water quality worldwide
Larsen, Matthew C.; Ahuja, Satinder; Eimers, Jo Leslie; Edited by Ahuja, Satinder
2013-01-01
Water quality and water quantity are closely linked. In all regions of the world, the quality and quantity of water must be considered together in order to sustain abundant water of the quality needed for drinking, irrigation, environmental health, industry, power generation, and recreation. Protecting and managing water to meet water needs requires comprehensive information and understanding of the impacts of natural settings and anthropogenic activities on water quality.
The evolution of blood pressure and the rise of mankind.
Schulte, Kevin; Kunter, Uta; Moeller, Marcus J
2015-05-01
Why is it that only human beings continuously perform acts of heroism? Looking back at our evolutionary history can offer us some potentially useful insight. This review highlights some of the major steps in our evolution-more specifically, the evolution of high blood pressure. When we were fish, the first kidney was developed to create a standardized internal 'milieu' preserving the primordial sea within us. When we conquered land as amphibians, the evolution of the lung required a low systemic blood pressure, which explains why early land vertebrates (amphibians, reptiles) are such low performers. Gaining independence from water required the evolution of an impermeable skin and a water-retaining kidney. The latter was accomplished twice with two different solutions in the two major branches of vertebrate evolution: mammals excrete nitrogenous waste products as urea, which can be utilized by the kidney as an osmotic agent to produce more concentrated urine. Dinosaurs and birds have a distinct nitrogen metabolism and excrete nitrogen as water-insoluble uric acid-therefore, their kidneys cannot use urea to concentrate as well. Instead, some birds have developed the capability to reabsorb water from their cloacae. The convergent development of a separate small circulation of the lung in mammals and birds allowed for the evolution of 'high blood-pressure animals' with better capillarization of the peripheral tissues allowing high endurance performance. Finally, we investigate why mankind outperforms any other mammal on earth and why, to this day, we continue to perform acts of heroism on our eternal quest for personal bliss. © The Author 2014. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.
Nanowires from dirty multi-crystalline Si for hydrogen generation
NASA Astrophysics Data System (ADS)
Li, Xiaopeng; Schweizer, Stefan L.; Sprafke, Alexander; Wehrspohn, Ralf B.
2013-09-01
Silicon nanowires are considered as a promising architecture for solar energy conversion systems. By metal assisted chemical etching of multi-crystalline upgraded metallurgical silicon (UMG-Si), large areas of silicon nanowires (SiNWs) with high quality can be produced on the mother substrates. These areas show a low reflectance comparable to black silicon. More interestingly, we find that various metal impurities inside UMG-Si are removed due to the etching through element analysis. A prototype cell was built to test the photoelectrochemical (PEC) properties of UMG-SiNWs for water splitting. The on-set potential for hydrogen evolution was much reduced, and the photocurrent density showed an increment of 35% in comparison with a `dirty' UMG-Si wafer.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-15
... (also called water quality criteria) for human health and aquatic life for toxic pollutants in the... Commission in 1996 adopted water quality criteria for human health and aquatic life for Water Quality Zones 2... Objectives for Toxic Pollutants for the Protection of Aquatic Life'', Table 6, ``Stream Quality Objectives...
Parkhurst, David L.; Christenson, Scott C.; Schlottmann, Jamie L.
1989-01-01
Beginning in 1986, the Congress annually has appropriated funds for the U.S. Geological Survey to test and refine concepts for a National Water-Quality Assessment (NAWQA) Program. The long-term goals of a full-scale program would be to:Provide a nationally consistent description of current water-quality conditions for a large part of the Nation's surface- and ground-water resources;Define long-term trends (or lack of trends) in water quality; andIdentify, describe, and explain, as possible, the major factors that affect the observed water-quality conditions and trends.The results of the NAWQA Program will be made available to water managers, policy makers, and the public, and will provide an improved scientific basis for evaluating the effectiveness of water-quality management programs.At present (1988), the assessment program is in a pilot phase in seven project areas throughout the country that represent diverse hydrologic environments and water-quality conditions. The Central Oklahoma aquifer project is one of three pilot ground-water projects. One of the initial activities performed by each pilot project was to compile, screen, and interpret the large amount of water-quality data available within each study unit.The purpose of this report is to assess the water quality of the Central Oklahoma aquifer using the information available through 1987. The scope of the work includes compiling data from Federal, State, and local agencies; evaluating the suitability of the information for conducting a regional water-quality assessment; mapping regional variations in major-ion chemistry; calculating summary statistics of the available water-quality data; producing maps to show the location and number of samples that exceeded water-quality standards; and performing contingency-table analyses to determine the relation of geologic unit and depth to the occurrence of chemical constituents that exceed water-quality standards. This report provides an initial description of water-quality conditions in the Central Oklahoma aquifer study unit. No attempt was made in this report to determine the causes for regional variations in major-ion chemistry or to examine the reasons that some chemical constituents exceed water-quality standards.
NASA Astrophysics Data System (ADS)
Nakagawa, Takashi; Spiegelman, Marc W.
2017-04-01
We investigate the influence of the mantle water content in the early Earth on that in the present mantle using numerical convection simulations that include three processes for redistribution of water: dehydration, partitioning of water into partially molten mantle, and regassing assuming an infinite water reservoir at the surface. These models suggest that the water content of the present mantle is insensitive to that of the early Earth. The initial water stored during planetary formation is regulated up to 1.2 OMs (OM = Ocean Mass; 1.4 ×1021 kg), which is reasonable for early Earth. However, the mantle water content is sensitive to the rheological dependence on the water content and can range from 1.2 to 3 OMs at the present day. To explain the evolution of mantle water content, we computed water fluxes due to subducting plates (regassing), degassing and dehydration. For weakly water dependent viscosity, the net water flux is almost balanced with those three fluxes but, for strongly water dependent viscosity, the regassing dominates the water cycle system because the surface plate activity is more vigorous. The increased convection is due to enhanced lubrication of the plates caused by a weak hydrous crust for strongly water dependent viscosity. The degassing history is insensitive to the initial water content of the early Earth as well as rheological strength. The degassing flux from Earth's surface is calculated to be approximately O (1013) kg /yr, consistent with a coupled model of climate evolution and mantle thermal evolution.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Peili; Li, Lin; Nordlund, Dennis
Electrochemical water splitting requires efficient water oxidation catalysts to accelerate the sluggish kinetics of water oxidation reaction. Here in this paper, we report a promisingly dendritic core-shell nickel-iron-copper metal/metal oxide electrode, prepared via dealloying with an electrodeposited nickel-iron-copper alloy as a precursor, as the catalyst for water oxidation. The as-prepared core-shell nickel-iron-copper electrode is characterized with porous oxide shells and metallic cores. This tri-metal-based core-shell nickel-iron-copper electrode exhibits a remarkable activity toward water oxidation in alkaline medium with an overpotential of only 180 mV at a current density of 10 mA cm -2. The core-shell NiFeCu electrode exhibits pH-dependent oxygenmore » evolution reaction activity on the reversible hydrogen electrode scale, suggesting that non-concerted proton-electron transfers participate in catalyzing the oxygen evolution reaction. To the best of our knowledge, the as-fabricated core-shell nickel-iron-copper is one of the most promising oxygen evolution catalysts.« less
Zhang, Peili; Li, Lin; Nordlund, Dennis; ...
2018-01-26
Electrochemical water splitting requires efficient water oxidation catalysts to accelerate the sluggish kinetics of water oxidation reaction. Here in this paper, we report a promisingly dendritic core-shell nickel-iron-copper metal/metal oxide electrode, prepared via dealloying with an electrodeposited nickel-iron-copper alloy as a precursor, as the catalyst for water oxidation. The as-prepared core-shell nickel-iron-copper electrode is characterized with porous oxide shells and metallic cores. This tri-metal-based core-shell nickel-iron-copper electrode exhibits a remarkable activity toward water oxidation in alkaline medium with an overpotential of only 180 mV at a current density of 10 mA cm -2. The core-shell NiFeCu electrode exhibits pH-dependent oxygenmore » evolution reaction activity on the reversible hydrogen electrode scale, suggesting that non-concerted proton-electron transfers participate in catalyzing the oxygen evolution reaction. To the best of our knowledge, the as-fabricated core-shell nickel-iron-copper is one of the most promising oxygen evolution catalysts.« less
Improved water electrolysis using magnetic heating of FeC-Ni core-shell nanoparticles
NASA Astrophysics Data System (ADS)
Niether, Christiane; Faure, Stéphane; Bordet, Alexis; Deseure, Jonathan; Chatenet, Marian; Carrey, Julian; Chaudret, Bruno; Rouet, Alain
2018-06-01
Water electrolysis enables the storage of renewable electricity via the chemical bonds of hydrogen. However, proton-exchange-membrane electrolysers are impeded by the high cost and low availability of their noble-metal electrocatalysts, whereas alkaline electrolysers operate at a low power density. Here, we demonstrate that electrocatalytic reactions relevant for water splitting can be improved by employing magnetic heating of noble-metal-free catalysts. Using nickel-coated iron carbide nanoparticles, which are prone to magnetic heating under high-frequency alternating magnetic fields, the overpotential (at 20 mA cm-2) required for oxygen evolution in an alkaline water-electrolysis flow-cell was decreased by 200 mV and that for hydrogen evolution was decreased by 100 mV. This enhancement of oxygen-evolution kinetics is equivalent to a rise of the cell temperature to 200 °C, but in practice it increased by 5 °C only. This work suggests that, in the future, water splitting near the equilibrium voltage could be possible at room temperature, which is currently beyond reach in the classic approach to water electrolysis.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS General Provisions § 131.2 Purpose. A water quality standard defines the water quality goals of a water... criteria necessary to protect the uses. States adopt water quality standards to protect public health or...
Code of Federal Regulations, 2010 CFR
2010-07-01
... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS General Provisions § 131.2 Purpose. A water quality standard defines the water quality goals of a water... criteria necessary to protect the uses. States adopt water quality standards to protect public health or...
NASA Astrophysics Data System (ADS)
Mortazavi-Naeini, M.; Bussi, G.; Hall, J. W.; Whitehead, P. G.
2016-12-01
The main aim of water companies is to have a reliable and safe water supply system. To fulfil their duty the water companies have to consider both water quality and quantity issues and challenges. Climate change and population growth will have an impact on water resources both in terms of available water and river water quality. Traditionally, a distinct separation between water quality and abstraction has existed. However, water quality can be a bottleneck in a system since water treatment works can only treat water if it meets certain standards. For instance, high turbidity and large phytoplankton content can increase sharply the cost of treatment or even make river water unfit for human consumption purposes. It is vital for water companies to be able to characterise the quantity and quality of water under extreme weather events and to consider the occurrence of eventual periods when water abstraction has to cease due to water quality constraints. This will give them opportunity to decide on water resource planning and potential changes to reduce the system failure risk. We present a risk-based approach for incorporating extreme events, based on future climate change scenarios from a large ensemble of climate model realisations, into integrated water resources model through combined use of water allocation (WATHNET) and water quality (INCA) models. The annual frequency of imposed restrictions on demand is considered as measure of reliability. We tested our approach on Thames region, in the UK, with 100 extreme events. The results show increase in frequency of imposed restrictions when water quality constraints were considered. This indicates importance of considering water quality issues in drought management plans.
Proceedings of the MECA Workshop on The Evoluation of the Martian Atmosphere
NASA Technical Reports Server (NTRS)
Carr, M. (Editor); James, P. (Editor); Conway, L. (Editor); Pepin, R. (Editor); Pollack, J. (Editor)
1985-01-01
Topics addressed include: Mars' volatile budget; climatic implications of martian channels; bulk composition of Mars; accreted water inventory; evolution of CO2; dust storms; nonlinear frost albedo feedback on Mars; martian atmospheric evolution; effects of asteroidal and cometary impacts; and water exchange between the regolith and the atmosphere/cap system over obliquity timescales.
Study of water masses variability in the Mediterranean Sea using in-situ data / NEMO-Med12 model.
NASA Astrophysics Data System (ADS)
Margirier, Félix; Testor, Pierre; Mortier, Laurent; Arsouze, Thomas; Bosse, Anthony; Houpert, Loic; Hayes, Dan
2016-04-01
In the past 10 years, numerous observation programs in the Mediterranean deployed autonomous platforms (moorings, argo floats, gliders) and thus considerably increased the number of in-situ observations and the data coverage. In this study, we analyse time series built with profile data on interannual scales. Sorting data in regional boxes, we follow the evolution of different water masses in the basin and generate indexes to characterize their evolution. We then put those indexes in relation with external (atmospheric) forcings and present an intercomparison with the NEMO-Med12 model to estimate both the skill of the model and the relevance of the data-sampling in reproducing the evolution of water masses properties.
NASA Astrophysics Data System (ADS)
Son, Y. T.; Chang, K. I.; Nam, S.; Kang, D. J.
2016-02-01
Coastal monitoring buoy (called it as ESROB) has been continually operated to monitor meteorological (wind, air temperature, air pressure, PAR) and oceanic properties (temperature, salinity, current, chlorophyll fluorescence, DO, turbidity) using equipment such as CTD, fluorometer and WQM (Water Quality Monitor) in the eastern coastal region of Korea (the East/Japan Sea) since April 2011. The ESROB produced temporal evolution of physical and biogeochemical parameters of the water column with high resolution of 10 min interval. In order to understand horizontal influence of physical and biogeochemical parameters on variation of subsurface chlorophyll maximum layer (SCM), interdisciplinary in-situ surveys with small R/V in the study area for about week were conducted in June/October 2014 and in May 2015. A wirewalker, a wave-driven vertically profiling platform (Rainville and Pinkel 2001), was also deployed at two points (about 30 m and 80 m water depth) along cross-shore direction with the ESROB for about one or two weeks with in-situ survey durations. The wirewalker was equipped with CTD, turbidity and chlorophyll a fluorometer profiler, which was completed approximately every 3 10 minute depending on sea surface state. The SCM was observed in almost every deployment nearest coast, except for June in 2014, with variation of semi- and diurnal time periods. Temporal evolution of the wirewalker showed that disappearance and reoccurrence of the SCM within the water column in October 2014, which was associated with vertical mixing induced by strong wind stress. Low salinity plume in the surface layer and shoaling of bottom cold water were concurrently observed after homogeneous water column, affecting another condition to the vertical distribution of chlorophyll a in this coastal region. Moreover in-situ observation with densely points and temporal interval for 1 day revealed that distribution with high concentration of chlorophyll a on isopycnal was association with the horizontal local circulation that has influence on stability (vertical stratification and shear) of the water column. Optical and biogeochemical parameter analyzed from the water samples, affecting on the variation of chlorophyll a concentration within the water column, will be also discussed in the presentation of Ocean Science Meeting.
40 CFR 131.20 - State review and revision of water quality standards.
Code of Federal Regulations, 2010 CFR
2010-07-01
... accordance with provisions of State law, EPA's water quality management regulation (40 CFR 130.3(b)(6)) and... quality standards. 131.20 Section 131.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Procedures for Review and Revision of Water Quality...
40 CFR 131.20 - State review and revision of water quality standards.
Code of Federal Regulations, 2012 CFR
2012-07-01
... quality standards. 131.20 Section 131.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Procedures for Review and Revision of Water Quality Standards § 131.20 State review and revision of water quality standards. (a) State review. The State shall...
40 CFR 131.20 - State review and revision of water quality standards.
Code of Federal Regulations, 2013 CFR
2013-07-01
... quality standards. 131.20 Section 131.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Procedures for Review and Revision of Water Quality Standards § 131.20 State review and revision of water quality standards. (a) State review. The State shall...
40 CFR 131.20 - State review and revision of water quality standards.
Code of Federal Regulations, 2014 CFR
2014-07-01
... quality standards. 131.20 Section 131.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Procedures for Review and Revision of Water Quality Standards § 131.20 State review and revision of water quality standards. (a) State review. The State shall...
40 CFR 227.31 - Applicable marine water quality criteria.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Applicable marine water quality... § 227.31 Applicable marine water quality criteria. Applicable marine water quality criteria means the criteria given for marine waters in the EPA publication “Quality Criteria for Water” as published in 1976...
40 CFR 227.31 - Applicable marine water quality criteria.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Applicable marine water quality... § 227.31 Applicable marine water quality criteria. Applicable marine water quality criteria means the criteria given for marine waters in the EPA publication “Quality Criteria for Water” as published in 1976...
40 CFR 227.31 - Applicable marine water quality criteria.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Applicable marine water quality... § 227.31 Applicable marine water quality criteria. Applicable marine water quality criteria means the criteria given for marine waters in the EPA publication “Quality Criteria for Water” as published in 1976...
Bennett, Trudy J.; Graham, Jennifer L.; Foster, Guy M.; Stone, Mandy L.; Juracek, Kyle E.; Rasmussen, Teresa J.; Putnam, James E.
2014-01-01
A quality-assurance plan for use in conducting continuous water-quality monitoring activities has been developed for the Kansas Water Science Center in accordance with guidelines set forth by the U.S. Geological Survey. This quality-assurance plan documents the standards, policies, and procedures used by the U.S. Geological Survey in Kansas for activities related to the collection, processing, storage, analysis, and release of continuous water-quality monitoring data. The policies and procedures that are documented in this quality-assurance plan for continuous water-quality monitoring activities complement quality-assurance plans for surface-water and groundwater activities in Kansas.
The quality of raw water for drinking water unit in Jakarta-Indonesia
NASA Astrophysics Data System (ADS)
Sidabutar, Noni Valeria; Hartono, Djoko M.; Soesilo, Tri Edhi Budhi; Hutapea, Reynold C.
2017-03-01
Water problems, i.e quality, quantity, continuity of clean water faced by the mostly urban area. Jakarta also faces similar issues, because the needs of society higher than the number of water fulfilled by the government. Moreover, Jakarta's water quality does not meet the standard set by the Government and heavily polluted by anthropogenic activities along its rivers. This research employs a quantitative research approach with the mix-method. It examines the raw water quality status for drinking water in West Tarum Canalin 2011-2015. The research results show water quality with this research, using water quality of with the water categorized as heavily-polluted category based on the Ministry of Environment's Decree No 115/2003 regarding the Guidelines for Determination of Water Quality Status. This present research also shown the water quality (parameters pH, temperature, Dissolved Oxygen (DO), Chemical Oxygen Demand (COD), and Biochemical Oxygen Demand (BOD)) from Jatiluhur Dam to the intake drinking water unit. In thirteen points of sampling also, the results obtained the parameters DO, COD, and BOD are fluctuating and exceed the standard.
40 CFR 130.8 - Water quality report.
Code of Federal Regulations, 2010 CFR
2010-07-01
... QUALITY PLANNING AND MANAGEMENT § 130.8 Water quality report. (a) Each State shall prepare and submit... quality data and problems identified in the 305(b) report, States develop water quality management (WQM... the 305(b) report should be analyzed through water quality management planning leading to the...
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.
Evolution of the human-water relationships in the Heihe River basin in the past 2000 years
NASA Astrophysics Data System (ADS)
Lu, Z.; Wei, Y.; Xiao, H.; Zou, S.; Xie, J.; Ren, J.; Western, A.
2015-05-01
This paper quantitatively analyzed the evolution of human-water relationships in the Heihe River basin of northern China over the past 2000 years by reconstructing the catchment water balance by partitioning precipitation into evapotranspiration and runoff. The results provided the basis for investigating the impacts of societies on hydrological systems. Based on transition theory and the rates of changes of the population, human water consumption and the area of natural oases, the evolution of human-water relationships can be divided into four stages: predevelopment (206 BC-AD 1368), take-off (AD 1368-1949), acceleration (AD 1949-2000), and the start of a rebalancing between human and ecological needs (post AD 2000). Our analysis of the evolutionary process revealed that there were large differences in the rate and scale of changes and the period over which they occurred. The transition of the human-water relationship had no fixed pattern. This understanding of the dynamics of the human-water relationship will assist policy makers in identifying management practices that require improvement by understanding how today's problems were created in the past, which may lead to more sustainable catchment management in the future.
Moran, Edward H.; Solin, Gary L.
2006-01-01
The Matanuska-Susitna Valley is in the northeastern part of the Cook Inlet Basin, Alaska, an area experiencing rapid population growth and development proximal to many lakes. Here water commonly flows between lakes and ground water, indicating interrelation between water quantity and quality. Thus concerns exist that poorer quality ground water may degrade local lake ecosystems. This concern has led to water-quality sampling in cooperation with the Alaska Department of Environmental Conservation and the Matanuska-Susitna Borough. A map showing the estimated altitude of the water table illustrates potential ground-water flow directions and areas where ground- and surface-water exchanges and interactions might occur. Water quality measured in selected wells and lakes indicates some differences between ground water and surface water. 'The temporal and spatial scarcity of ground-water-level and water-quality data limits the analysis of flow direction and water quality. Regionally, the water-table map indicates that ground water in the eastern and southern parts of the study area flows southerly. In the northcentral area, ground water flows predominately westerly then southerly. Although ground and surface water in most areas of the Matanuska-Susitna Valley are interconnected, they are chemically different. Analyses of the few water-quality samples collected in the area indicate that dissolved nitrite plus nitrate and orthophosphorus concentrations are higher in ground water than in surface water.'
Yu, Shil; Sun, Ping-an; Du, Wen-yue; He, Shi-yi; Li, Rui
2015-01-01
In this paper, observation and sampling were taken three times a month in a hydrological year for three typical sections of the middle and upper reaches of the Xijiang River basin, based on the data of hydrochemistry and flow, the article mainly discusses the evolution process of hydrochemistry in river under natural process and impact of human activity. Hydrochemical characteristics of 116. samples were analyzed in the study area. The hydrochemistry type in the middle and upper reaches of the Xijiang River basin belonged to HCO3- -Ca2+ type, and the chemical weathering type mainly came from carbonate rock weathering. Ca2+ and HCO3- were the main cations and anions, which reflected that hydrochemical characteristics of river in karst area mainly affected by the dissolution of carbonate rock. Na, Mg2, Ca2+ and Cl- mainly affected by natural conditions, the impact of human activity was little. K+, NO3-, SO4(2-) and HCO3- were affected by human activity in different degrees, and it showed different influence ways. This study had an important significance for the change of river hydrochemistry, water quality characteristics, and the effect on substance transported fluxes in the downstream of Pearl River and water quality protection in South China Monsoon Area.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-30
... Activities; Proposed Collection; Comment Request; Water Quality Standards (Renewal) AGENCY: Environmental... States and certain authorized Indian Tribes that adopt water quality standards under the Clean Water Act; and water dischargers subject to certain requirements related to water quality standards in the Great...
Jordan, P.R.; Stamer, J.K.
1991-01-01
Beginning in 1986, the U.S. Congress appropriated funds for the U.S. Geological Survey to test and refine concepts for a National Water-Quality Assessment (NAWQA) Program. The long-term goals of the full-scale program are to: (1) provide a nationally consistent description of current water-quality conditions for a large part of the Nation's surface- and ground-water resources; (2) define long-term trends (or lack of trends) in water quality; and (3) identify, describe, and explain, insofar as possible, the major factors that affect current conditions and trends in water quality. This information, obtained on a continuing basis, will be made available to water managers, policy makers, and the public to provide an improved scientific basis for evaluating the effectiveness of water-quality-management programs and for predicting the likely effects of contemplated changes in land-and water-management practices. At present (1990), the assessment program is in a pilot phase in seven areas that represent diverse hydrologic environments and water-quality conditions.This report completes one of the first activities undertaken as part of the lower Kansas River basin pilot study, which was to compile, screen, and interpret available water-quality data for the study unit through 1986. The report includes information on the sources and types of water-quality data available, the utility of available water-quality data for assessment purposes, and a description of current water-quality conditions and trends and their relation to natural and human factors.
NASA Astrophysics Data System (ADS)
You, Jinjun; Gan, Hong; Wang, Lin; Bi, Xue; Du, Sisi
2010-05-01
The evolution of groundwater is one of the key problems of water cycle study. It is a result of joint effect of natural condition and human activities, but until now the driving forces of groundwater system evolution were not fully understood due to the complexity of groundwater system structures and the uncertainty of affecting factors. Geology, precipitation and human activity are the main factors affecting the groundwater system evolution and interact each other, but the influence of such three factors on groundwater system are not clarified clearly on a macroscopic scale. The precipitation changes the volume of water recharge and the groundwater pumping effect the discharge of groundwater. Another important factor influencing balance of groundwater storage is the underlaying that affects the renewablility of groundwater. The underlaying is decided mainly by geological attributes but also influenced by human activited. The macroscopic environment of groundwater evolves under the natural and anthropic factors. This paper study the general law of groundwater evolution among the factors based on the case study in Haihe River Basin, a typical area with dramatic groundwater change under natural precipitation attenuation and gradually increase of water suuply. Haihe River Basin is located in north-China, covers an area of 320,041 km2 with over 40% plain areas. The plain area of Haihe Basin is densely populated with many large and medium-sized cities, including metropolis of Beijing and Tianjin, and concentrated irrigated areas, playing important roles in China's economy and food production. It is the unique basin where groundwater occupies majority of total water supply in China. Long-term groundwater over-exploitation causes a series of ecological and environmental problems that threats the sustainable development. In this paper, the historical process of groundwater balance in Haihe Basin is divided into three phases by decrease of rainfall and increase of water pumping. The different problems caused by groundwater shrinkage are summarized. The volume of recharge from natural precipitation and artificial water cycle, natural evaporation and groundwater exploitation are analyzed based on water balance. Through the historical data analysis the changing trend of coefficients of groundwater balance discovers the evolution of groundwater. The general law is concluded with deeper analysis displays the contribution of natural and artificial factors causing deterioration of groundwater balance. A general law of groundwater evolution is put forward to describe the affection of both natural and anthropogenic factors with a relation curve. Considering the water demand of future socio-economic development in Haihe River Basin, the prospective of future vision of groundwater cycle is analyzed by the law of groundwater evolution. Iterated scenario analysis based on comparison of ameliorative function on groundwater balance to point out reasonable control on groundwater exploitation and rational water allocation under the condition of completion of South-to-North Water Transfer Project that could bring more than 7 billion m3 into Haihe River Basin from Yantze River. Finally, the advantages and disadvantages are concluded through the case study and the farther research in this field is pointed out.
Yang, Yuan; Wang, Yan-Zhai; Fang, Zhen; Yu, Yang-Yang; Yong, Yang-Chun
2018-02-01
Toxicity assessment of water is of great important to the safety of human health and to social security because of more and more toxic compounds that are spilled into the aquatic environment. Therefore, the development of fast and reliable toxicity assessment methods is of great interest and attracts much attention. In this study, by using the electrochemical activity of Shewanella oneidensis MR-1 cells as the toxicity indicator, 3,5-dichlorophenol (DCP) as the model toxic compound, a new biosensor for water toxicity assessment was developed. Strikingly, the presence of DCP in the water significantly inhibited the maximum current output of the S. oneidensis MR-1 in a three-electrode system and also retarded the current evolution by the cells. Under the optimized conditions, the maximum current output of the biosensor was proportional to the concentration of DCP up to 30 mg/L. The half maximal inhibitory concentration of DCP determined by this biosensor is about 14.5 mg/L. Furthermore, simultaneous monitoring of the retarded time (Δt) for current generation allowed the identification of another biosensor signal in response to DCP which could be employed to verify the electrochemical result by dual confirmation. Thus, the present study has provided a reliable and promising approach for water quality assessment and risk warning of water toxicity.
A national-scale analysis of the impacts of drought on water quality in UK rivers
NASA Astrophysics Data System (ADS)
Coxon, G.; Howden, N. J. K.; Freer, J. E.; Whitehead, P. G.; Bussi, G.
2015-12-01
Impacts of droughts on water quality qre difficult to quanitify but are essential to manage ecosystems and maintain public water supply. During drought, river water quality is significantly changed by increased residence times, reduced dilution and enhanced biogeochemical processes. But, the impact severity varies between catchments and depends on multiple factors including the sensitivity of the river to drought conditions, anthropogenic influences in the catchment and different delivery patterns of key nutrient, contaminant and mineral sources. A key constraint is data availability for key water quality parameters such that impacts of drought periods on certain determinands can be identified. We use national-scale water quality monitoring data to investigate the impacts of drought periods on water quality in the United Kingdom (UK). The UK Water Quality Sampling Harmonised Monitoring Scheme (HMS) dataset consists of >200 UK sites with weekly to monthly sampling of many water quality variables over the past 40 years. This covers several major UK droughts in 1975-1976, 1983-1984,1989-1992, 1995 and 2003, which cover severity, spatial and temporal extent, and how this affects the temporal impact of the drought on water quality. Several key water quality parameters, including water temperature, nitrate, dissolved organic carbon, orthophosphate, chlorophyll and pesticides, are selected from the database. These were chosen based on their availability for many of the sites, high sampling resolution and importance to the drinking water function and ecological status of the river. The water quality time series were then analysed to investigate whether water quality during droughts deviated significantly from non-drought periods and examined how the results varied spatially, for different drought periods and for different water quality parameters. Our results show that there is no simple conclusion as to the effects of drought on water quality in UK rivers; impacts are diverse both in terms of timing, magnitude and duration. We consider several scenarios in which management interventions may alleviate water quality pressures, and discuss how the many interacting factors need to be better characterised to support detailed mechanistic models to improve our process understanding.
Oblinger, Carolyn J.
2004-01-01
The Triangle Area Water Supply Monitoring Project was initiated in October 1988 to provide long-term water-quality data for six area water-supply reservoirs and their tributaries. In addition, the project provides data that can be used to determine the effectiveness of large-scale changes in water-resource management practices, document differences in water quality among water-supply types (large multiuse reservoir, small reservoir, run-of-river), and tributary-loading and in-lake data for water-quality modeling of Falls and Jordan Lakes. By September 2001, the project had progressed in four phases and included as many as 34 sites (in 1991). Most sites were sampled and analyzed by the U.S. Geological Survey. Some sites were already a part of the North Carolina Division of Water Quality statewide ambient water-quality monitoring network and were sampled by the Division of Water Quality. The network has provided data on streamflow, physical properties, and concentrations of nutrients, major ions, metals, trace elements, chlorophyll, total organic carbon, suspended sediment, and selected synthetic organic compounds. Project quality-assurance activities include written procedures for sample collection, record management and archive, collection of field quality-control samples (blank samples and replicate samples), and monitoring the quality of field supplies. In addition to project quality-assurance activities, the quality of laboratory analyses was assessed through laboratory quality-assurance practices and an independent laboratory quality-control assessment provided by the U.S. Geological Survey Branch of Quality Systems through the Blind Inorganic Sample Project and the Organic Blind Sample Project.
From mountains to the ocean: quantifying connectivity along the river corridor
NASA Astrophysics Data System (ADS)
Gomez-Velez, J. D.; Harvey, J. W.
2015-12-01
Rivers are the landscape's arteries; they convey water, solutes, energy, and living organisms from the hillslopes, floodplains, aquifers, and atmosphere to the oceans. As water moves along this complex circulatory system, it is continuously exchanged with the surrounding alluvial aquifer, termed hyporheic exchange, which strongly conditions and constrains the biogeochemical evolution of water at the local scale with basin-scale consequences. Over the last two decades, considerable efforts have focused on the use of detailed mathematical models to explore the hydrodynamics and biogeochemical effect of hyporheic exchange at the scale of individual channel morphologies. While these efforts are essential to gain mechanistic understanding, their computational demand makes them impractical for basin applications. In this talk, a parsimonious but physically based model of hyporheic flow for application in large river basins is presented: Networks with EXchange and Subsurface Storage (NEXSS). At the core of NEXSS are the up-scaling of detailed mathematical models and a characterization of the channel geometry, geomorphic features, and related hydraulic drivers based on scaling equations from the literature and readily accessible information such as river discharge, width, grain size, sinuosity, channel slope, and regional groundwater gradients. As a proof-of-concept, we use NEXSS to characterize the spatial and temporal variability of hyporheic exchange and denitrification potential along the Mississippi River basin. This modeling approach allows us to map the location of critical hot spots for biogeochemical transformation, their geomorphic drivers, and cumulative effect. Finally, we discuss new avenues to incorporate exchange with floodplains and ponded waters, which also play a key role in water quality along the river corridor. This new modeling approach is critical to transition from purely empirical continental models of water quality to hybrid approaches that incorporate fundamental physics and take advantage of available hydrogeomorphic data. In particular, hybrid models will be instrumental for predicting outcomes of river basin management practices under present and future socio-economic and climatic conditions.
Assessment of irrigation water quality. A proposal of a quality profile.
Almeida, César; Quintar, Silvya; González, Patricia; Mallea, Miguel
2008-07-01
Water quality indices provide a simple and understandable tool for managers on the quality and possible uses for irrigation water, however an individual quality factor alone is not enough to evaluate the irrigation water quality because it could be restrictive and sometime it could give an unfavorable qualification. The aim of this paper was propose a quality profile of irrigation water using the preexisting water quality indices to be applied to arid and semi-arid regions. As a case studied, the water of the Del Molle River (Nogolí, San Luis, Argentina) was researched. Samples were collected during the period October 2005-May 2006. Conductivity, pH, total hardness, sulphate, nitrate, nitrite, alkalinity, chloride, sodium, potassium, TDS, DO and phosphate were analyzed. The irrigation water quality, according to Riverside Norm, belongs to C(2)-S(1) class, according to Wilcox Norm as excellent to good, according to Scott quality factor it is good and according to SAR < 10 and according to RCS it is recommendable. From the obtained data, it can be concluded that the water quality profile was good, so it is useful for normal irrigation agriculture.
Spahr, N.E.
2003-01-01
Introduction: Population growth and changes in land-use practices have the potential to affect water quality and quantity in the upper Gunnison River basin. In 1995, the U.S. Geological Survey (USGS), in cooperation with local sponsors, City of Gunnison, Colorado River Water Conservation District, Crested Butte South Metropolitan District, Gunnison County, Mount Crested Butte Water and Sanitation District, National Park Service, Town of Crested Butte, and Upper Gunnison River Water Conservancy District, established a water-quality monitoring program in the upper Gunnison River basin to characterize current water-quality conditions and to assess the effects of increased urban development and other land-use changes on water quality. The monitoring network has evolved into two groups of stations, stations that are considered as long term and stations that are rotational. The long-term stations are monitored to assist in defining temporal changes in water quality (how conditions have changed over time). The rotational stations are monitored to assist in the spatial definition of water-quality conditions (how conditions differ throughout the basin) and to address local and short term concerns. Another group of stations (rotational group 2) will be chosen and sampled beginning in water year 2004. Annual summaries of the water-quality data from the monitoring network provide a point of reference for discussions regarding water-quality sampling in the upper Gunnison River basin. This summary includes data collected during water year 2002. The introduction provides a map of the sampling locations, definitions of terms, and a one-page summary of selected water-quality conditions at the network stations. The remainder of the summary is organized around the data collected at individual stations. Data collected during water year 2002 are compared to historical data (data collected for this network since 1995), state water-quality standards, and federal water-quality guidelines. Data were collected during water year 2002 following USGS protocols (U.S. Geological Survey, variously dated).
NASA Astrophysics Data System (ADS)
Baker, V. R.
2013-12-01
Planetary habitability may fluctuate episodically against a background provided by the co-evolution of a planet's mineral/rock (geosphere) components and its water (hydrosphere) in relation to its position in a circumstellar system. The water/rock (geosphere/hydrosphere) co-evolution can be inferred from the geological histories of the terrestrial planets of the solar system, particularly from the very extensive understanding of Earth and Mars. Habitability and water/rock co-evolution have components that are tychistic (i.e., driven by chance) and anancastic (i.e., dynamically driven largely by deterministic forces). They also have a final, end-directed (i.e., teleomatic) aspect that operates in accordance with natural laws. This is a larger perspective on the idea of planetary habitability than is generally associated with an astronomical approach, and it incorporates additional insights from a geological perspective on the issue. The geological histories of Mars and Earth are punctuated with critical, short-term epochs of extreme change, which for Earth are known to be associated with major disruptions of its biosphere. These catastrophic epochs can be described as a type of non-Darwinian evolution that was envisioned by the geologist Clarence King. In an 1877 paper King proposed that accelerated evolutionary change occurs during sudden environmental disruptions. Such Kingian disruptions in mineral/rock and water evolution mark the planetary histories of Mars and Earth, including the early formation and condensation of a steam atmosphere, an impacting cataclysm at about 3.9 to 4 Ga, episodes of concentrated volcanism and tectonism, and associated rapid changes in the linked atmosphere and hydrosphere. These disruptions are closely tied to migrations of water between different planetary reservoirs, the nature of planetary accretion, the origin of a physically coupled atmosphere and ocean, the prospects for initiating plate tectonics, and punctuated greenhouse-to-icehouse climatic transitions. Recent discoveries from Mars missions reveal the extensive role of water in generating sedimentary rocks, active and relict glacial and periglacial features, aqueous weathering products (clay minerals and sulfates), alluvial fans and deltas, the extensive development of paleolakes, and even a probable, though transient ocean. The latter may have formed episodically, associated with episodes of intensive volcanism that disrupted a water-ice-rich permafrost, thereby transferring much of the hydrosphere f
Code of Federal Regulations, 2011 CFR
2011-07-01
... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Federally Promulgated Water Quality Standards § 131.31 Arizona. (a) [Reserved] (b) The following waters have... R18-11-101 (which is available from the Arizona Department of Environmental Quality, Water Quality...
Code of Federal Regulations, 2010 CFR
2010-07-01
... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Federally Promulgated Water Quality Standards § 131.31 Arizona. (a) [Reserved] (b) The following waters have... R18-11-101 (which is available from the Arizona Department of Environmental Quality, Water Quality...
Code of Federal Regulations, 2013 CFR
2013-07-01
... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Federally Promulgated Water Quality Standards § 131.31 Arizona. (a) [Reserved] (b) The following waters have... R18-11-101 (which is available from the Arizona Department of Environmental Quality, Water Quality...
Code of Federal Regulations, 2012 CFR
2012-07-01
... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Federally Promulgated Water Quality Standards § 131.31 Arizona. (a) [Reserved] (b) The following waters have... R18-11-101 (which is available from the Arizona Department of Environmental Quality, Water Quality...
Code of Federal Regulations, 2014 CFR
2014-07-01
... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Federally Promulgated Water Quality Standards § 131.31 Arizona. (a) [Reserved] (b) The following waters have... R18-11-101 (which is available from the Arizona Department of Environmental Quality, Water Quality...
INTEGRATING PROBABILISTIC AND FIXED-SITE MONITORING FOR ROBUST WATER QUALITY ASSESSMENTS
Determining the extent of water-quality degradation, controlling nonpoint sources, and defining allowable amounts of contaminants are important water-quality issues defined in the Clean Water Act that require new monitoring data. Probabilistic, randomized stream water-quality mon...
Massoud, M A; Maroun, R; Abdelnabi, H; Jamali, I I; El-Fadel, M
2013-04-01
This paper presents a comparative assessment of public perception of drinking water quality in two underprivileged urban areas in Lebanon and Jordan with nearly similar cultural and demographic characteristics. It compares the quality of bottled water to the quality of the drinking water supplied through the public network and examines the economic implications of bottled water consumption in the two study areas. Participants' perception of the quality of drinking water provided via the public network was generally negative, and bottled water was perceived to be of better quality in both areas, thus affecting drinking water preferences and consumption patterns. The results reveal that the quality of bottled water is questionable in areas that lack enforcement of water quality standards, thus adding to the burden of an already disadvantaged community. Both areas demonstrated a considerable cost incurred for purchasing bottled water in low income communities reaching up to 26 % of total income.
Cheung, Carol C; D'Arrigo, Corrado; Dietel, Manfred; Francis, Glenn D; Fulton, Regan; Gilks, C Blake; Hall, Jacqueline A; Hornick, Jason L; Ibrahim, Merdol; Marchetti, Antonio; Miller, Keith; van Krieken, J Han; Nielsen, Soren; Swanson, Paul E; Taylor, Clive R; Vyberg, Mogens; Zhou, Xiaoge; Torlakovic, Emina E
2017-04-01
The numbers of diagnostic, prognostic, and predictive immunohistochemistry (IHC) tests are increasing; the implementation and validation of new IHC tests, revalidation of existing tests, as well as the on-going need for daily quality assurance monitoring present significant challenges to clinical laboratories. There is a need for proper quality tools, specifically tissue tools that will enable laboratories to successfully carry out these processes. This paper clarifies, through the lens of laboratory tissue tools, how validation, verification, and revalidation of IHC tests can be performed in order to develop and maintain high quality "fit-for-purpose" IHC testing in the era of precision medicine. This is the final part of the 4-part series "Evolution of Quality Assurance for Clinical Immunohistochemistry in the Era of Precision Medicine."
Falk, Sarah E.; Anderholm, Scott K.; Engdahl, Nicholas B.
2011-01-01
The Albuquerque Bernalillo County Water Utility Authority (ABCWUA) is supplementing the municipal water supply for Albuquerque, New Mexico, and the surrounding area with water diverted from the Rio Grande. The distribution of surface water for municipal supply has raised questions about the quality of water in the Rio Grande and the possibility of contaminants in the water. The U.S. Geological Survey (USGS), in cooperation with ABCWUA, has compiled existing water-quality data collected on the Rio Grande and its main tributary, the Rio Chama, by various Federal and State agencies to provide a comprehensive overview of water quality in the Rio Grande basin upstream from Albuquerque. This report describes selected water-quality investigations conducted by various Federal and State agencies and 2007 USGS surface-water-quality investigations and data-collection activities and presents a statistical summary of selected water-quality data collected on the Rio Grande and the Rio Chama in central and northern New Mexico
Hou, Dibo; Song, Xiaoxuan; Zhang, Guangxin; Zhang, Hongjian; Loaiciga, Hugo
2013-07-01
An event-driven, urban, drinking water quality early warning and control system (DEWS) is proposed to cope with China's urgent need for protecting its urban drinking water. The DEWS has a web service structure and provides users with water quality monitoring functions, water quality early warning functions, and water quality accident decision-making functions. The DEWS functionality is guided by the principles of control theory and risk assessment as applied to the feedback control of urban water supply systems. The DEWS has been deployed in several large Chinese cities and found to perform well insofar as water quality early warning and emergency decision-making is concerned. This paper describes a DEWS for urban water quality protection that has been developed in China.
Tsukamoto fuzzy implementation to identify the pond water quality of koi
NASA Astrophysics Data System (ADS)
Qur'ania, A.; Verananda, D. I.
2017-01-01
The colour quality of koi was affected by the water quality in the pond. Koi fish have a diversity of types differentiated based on the body colour groups, such as one colour pattern, two colour patterns, three colours patterns and even more. Each colour characteristic of the koi have different handling, particularly in the handling of water quality, this is because the colour pigments in the body was affected by the composition of water quality include temperature, pH, TDS, do and salinity. The data of koi fish used were sanke, sowa, kohaku, shiro, yamabuki, ogon and chagoi. The aim of this study is to make an application to inform the condition of the pool water quality that can help breeders to know the water quality that will improve the handling strategies through water media. Tsukamoto Fuzzy method used to produce the three outputs namely water quality, water grade, and water conditions. The output of water quality consists of four categories, namely optimal, moderate, poor, and very poor. The output of water grade consists of grade A to D, while the output of water conditions consist of an excellent, good, bad, and very bad. Input to the application consists of five parameters, namely water temperature, pH, TDS, do and salinity.
Spahr, Norman E.; Hartle, David M.; Diaz, Paul
2008-01-01
Population growth and changes in land use have the potential to affect water quality and quantity in the upper Gunnison River Basin. In 1995, the U.S. Geological Survey (USGS), in cooperation with the Bureau of Land Management, City of Gunnison, Colorado River Water Conservation District, Crested Butte South Metropolitan District, Gunnison County, Hinsdale County, Mount Crested Butte Water and Sanitation District, National Park Service, Town of Crested Butte, Upper Gunnison River Water Conservancy District, and Western State College, established a water-quality monitoring program in the upper Gunnison River Basin to characterize current water-quality conditions and to assess the effects of increased urban development and other land-use changes on water quality. The monitoring network has evolved into two groups of stations - stations that are considered long term and stations that are considered rotational. The long-term stations are monitored to assist in defining temporal changes in water quality (how conditions may change over time). The rotational stations are monitored to assist in the spatial definition of water-quality conditions (how conditions differ throughout the basin) and to address local and short-term concerns. Some stations in the rotational group were changed beginning in water year 2007. Annual summaries of the water-quality data from the monitoring network provide a point of reference for discussions regarding water-quality monitoring in the upper Gunnison River Basin. This summary includes data collected during water years 2004 and 2005. The introduction provides a map of the sampling sites, definitions of terms, and a one-page summary of selected water-quality conditions at the network stations. The remainder of the summary is organized around the data collected at individual stations. Data collected during water years 2004 and 2005 are compared to historical data, State water-quality standards, and Federal water-quality guidelines. Data were collected following USGS protocols.
Solberg, P.A.; Moore, Bryan; Smits, Dennis
2009-01-01
Population growth and changes in land use have the potential to affect water quality and quantity in the upper Gunnison River basin. In 1995, the U.S. Geological Survey (USGS), in cooperation with the Bureau of Land Management, City of Gunnison, Colorado River Water Conservation District, Crested Butte South Metropolitan District, Gunnison County, Hinsdale County, Mount Crested Butte Water and Sanitation District, National Park Service, Town of Crested Butte, Upper Gunnison River Water Conservancy District, and Western State College established a water-quality monitoring program in the upper Gunnison River basin to characterize current water-quality conditions and to assess the effects of increased urban development and other land-use changes on water quality. The monitoring network has evolved into two groups of stations - stations that are considered long term and stations that are considered rotational. The long-term stations are monitored to assist in defining temporal changes in water quality (how conditions may change over time). The rotational stations are monitored to assist in the spatial definition of water-quality conditions (how conditions differ throughout the basin) and to address local and short-term concerns. Some stations in the rotational group were changed beginning in water year 2007. Annual summaries of the water-quality data from the monitoring network provide a point of reference for discussions regarding water-quality monitoring in the upper Gunnison River basin. This summary includes data collected during water years 2006 and 2007. The introduction provides a map of the sampling sites, definitions of terms, and a one-page summary of selected water-quality conditions at the network stations. The remainder of the summary is organized around the data collected at individual stations. Data collected during water years 2006 and 2007 are compared to historical data, State water-quality standards, and Federal water-quality guidelines. Data were collected following USGS protocols (U.S. Geological Survey, variously dated).
Landscape co-evolution and river discharge.
NASA Astrophysics Data System (ADS)
van der Velde, Ype; Temme, Arnaud
2015-04-01
Fresh water is crucial for society and ecosystems. However, our ability to secure fresh water resources under climatic and anthropogenic change is impaired by the complexity of interactions between human society, ecosystems, soils, and topography. These interactions cause landscape properties to co-evolve, continuously changing the flow paths of water through the landscape. These co-evolution driven flow path changes and their effect on river runoff are, to-date, poorly understood. In this presentation we introduce a spatially distributed landscape evolution model that incorporates growing vegetation and its effect on evapotranspiration, interception, infiltration, soil permeability, groundwater-surface water exchange and erosion. This landscape scale (10km2) model is calibrated to evolve towards well known empirical organising principles such as the Budyko curve and Hacks law under different climate conditions. To understand how positive and negative feedbacks within the model structure form complex landscape patterns of forests and peat bogs that resemble observed landscapes under humid and boreal climates, we analysed the effects of individual processes on the spatial distribution of vegetation and river peak and mean flows. Our results show that especially river peak flows and droughts decrease with increasing evolution of the landscape, which is a result that has direct implications for flood management.
Heptanuclear CoII5CoIII2 Cluster as Efficient Water Oxidation Catalyst.
Xu, Jia-Heng; Guo, Ling-Yu; Su, Hai-Feng; Gao, Xiang; Wu, Xiao-Fan; Wang, Wen-Guang; Tung, Chen-Ho; Sun, Di
2017-02-06
Inspired by the transition-metal-oxo cubical Mn 4 CaO 5 in photosystem II, we herein report a disc-like heptanuclear mixed-valent cobalt cluster, [Co II 5 Co III 2 (mdea) 4 (N 3 ) 2 (CH 3 CN) 6 (OH) 2 (H 2 O) 2 ·4ClO 4 ] (1, H 2 mdea = N-methyldiethanolamine), for photocatalytic oxygen evolution. The topology of the Co 7 core resembles a small piece of cobaltate protected by terminal H 2 O, N 3 - , CH 3 CN, and multidentate N-methyldiethanolamine at the periphery. Under the optimal photocatalytic conditions, 1 exhibits water oxidation activity with a turnover number (TON) of 210 and a turnover frequency (TOF initial ) of 0.23 s -1 . Importantly, electrospray mass spectrometry (ESI-MS) was used to not only identify the possible main active species in the water oxidation reaction but also monitor the evolutions of oxidation states of cobalt during the photocatalytic reactions. These results shed light on the design concept of new water oxidation catalysts and mechanism-related issues such as the key active intermediate and oxidation state evolution in the oxygen evolution process. The magnetic properties of 1 were also discussed in detail.
NASA Astrophysics Data System (ADS)
Djebebe-Ndjiguim, Chantal; Foto, Eric; Backo, Salé; Nguerekossi, Bruno; Zoudamba, Narcisse; Basse-Keke, Eric; Allahdin, Oscar; Huneau, Frédéric; Garel, Emilie; Celle-Jeanton, Hélène; Mabingui, Joseph
2017-04-01
Groundwater is a key factor in the socio-economic development of African societies. This is particularly true for the Lake Chad Basin countries for which groundwater is the main water resource for both drinking water supply for population and agriculture, whether small or large scale. The Central African Republic (CAR) occupies a strategic place in the Lake Chad Basin since most waters feeding the different tributaries of the Chari River, which is the main water source of the Lake Chad, are originating from its territory. Indeed, the Northern CAR and particularly the Ouham Province, at the head of the whole Chad endoreic watershed, benefits from favourable rainfall conditions. Unfortunately, very little hydrological and hydrogeological information is available for this area which has never been investigated in terms of geochemical and isotope characterisation. The only available spares technical and scientific investigations over the area are dating from the 1960's. Unfortunately the Lake Chad basin has undergone strong climatological evolutions since the 1970's and hydrological information needs to be updated. The objectives of this study are to characterise groundwater from the Ouham Province in order to better appreciate the hydrogeological processes taking place in the recharge area of the Southern Lake Chad Basin. Isotope hydrology combined with geochemistry of groundwater has now proven being the best approach in under-documented territories to have a first diagnostic on the dynamics and quality of available resources. In this purpose combined hydrogeochemical and isotopic investigations (18O, 2H and 3H of the water molecule) have been launched to constrain groundwater origin, recharge processes, quality, residence time and anthropogenic fingerprint on aquifers. After two sampling campaigns it was possible to draw a general pattern of the hydrogeological and hydrochemical conditions in the region. The Ouham province is mostly composed of Precambrian substratum rocks. Only the Northern edge, neighbouring the Chad Republic, is made of surface Tertiary formations of the Continental Terminal. This geological duality is clearly reflected in the geochemistry of groundwater, but despite an increase in the population and in the agricultural activity the overall quality is still good apart for a few wells located in the close vicinity of human settling, and already strongly influenced by nitrate contamination. The isotopic signature of groundwater is clearly modern and identical to the one of local rainfall, and very close to the regional water line of Bangui (GNIP-IAEA). Tritium data are mostly similar to the modern rainfall input but a few wells and boreholes tend to indicate the existence in the underground of slow-dynamic groundwater. In the end, and considering the local amount of rainfall (1500mm/year) the quality of the groundwater potential as a good quality water supply resource is confirmed, and indications towards the possibility of a development of the exploitation are provided.
National Recommended Water Quality Criteria
The National Recommended Water Quality Criteria is a compilation of national recommended water quality criteria for the protection of aquatic life and human health in surface water for approximately 150 pollutants. These criteria provide guidance for states and tribes to use in adopting water quality standards.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-23
... Plan to update the Commission's human health and aquatic life stream quality objectives (also called... DELAWARE RIVER BASIN COMMISSION 18 CFR Part 410 Amendments to the Water Quality Regulations, Water Code and Comprehensive Plan To Update Water Quality Criteria for Toxic Pollutants in the Delaware...
Code of Federal Regulations, 2011 CFR
2011-07-01
...) water quality criteria shall be based on the following: (i) For aquatic life criteria: The pollutant... quality which assures protection of public water supplies; assures the protection and propagation of a... maintenance of water quality which assures protection of public water supplies; assures the protection and...
Code of Federal Regulations, 2012 CFR
2012-07-01
...) water quality criteria shall be based on the following: (i) For aquatic life criteria: The pollutant... quality which assures protection of public water supplies; assures the protection and propagation of a... maintenance of water quality which assures protection of public water supplies; assures the protection and...
Code of Federal Regulations, 2014 CFR
2014-07-01
...) water quality criteria shall be based on the following: (i) For aquatic life criteria: The pollutant... quality which assures protection of public water supplies; assures the protection and propagation of a... maintenance of water quality which assures protection of public water supplies; assures the protection and...
Code of Federal Regulations, 2013 CFR
2013-07-01
...) water quality criteria shall be based on the following: (i) For aquatic life criteria: The pollutant... quality which assures protection of public water supplies; assures the protection and propagation of a... maintenance of water quality which assures protection of public water supplies; assures the protection and...
Code of Federal Regulations, 2010 CFR
2010-07-01
...) water quality criteria shall be based on the following: (i) For aquatic life criteria: The pollutant... quality which assures protection of public water supplies; assures the protection and propagation of a... maintenance of water quality which assures protection of public water supplies; assures the protection and...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-25
... DELAWARE RIVER BASIN COMMISSION 18 CFR Part 410 Proposed Amendments to the Water Quality Regulations, Water Code and Comprehensive Plan To Update Water Quality Criteria for pH AGENCY: Delaware River... public hearing to receive comments on proposed amendments to the Commission's Water Quality Regulations...
NASA Astrophysics Data System (ADS)
van Oel, P. R.; Alfredo, K. A.; Russo, T. A.
2015-12-01
Sustainable water management typically emphasizes water resource quantity, with focus directed at availability and use practices. When attention is placed on sustainable water quality management, the holistic, cross-sector perspective inherent to sustainability is often lost. Proper water quality management is a critical component of sustainable development practices. However, sustainable development definitions and metrics related to water quality resilience and management are often not well defined; water quality is often buried in large indicator sets used for analysis, and the policy regulating management practices create sector specific burdens for ensuring adequate water quality. In this research, we investigated the methods by which water quality is evaluated through internationally applied indicators and incorporated into the larger idea of "sustainability." We also dissect policy's role in the distribution of responsibility with regard to water quality management in the United States through evaluation of three broad sectors: urban, agriculture, and environmental water quality. Our research concludes that despite a growing intention to use a single system approach for urban, agricultural, and environmental water quality management, one does not yet exist and is even hindered by our current policies and regulations. As policy continues to lead in determining water quality and defining contamination limits, new regulation must reconcile the disparity in requirements for the contaminators and those performing end-of-pipe treatment. Just as the sustainable development indicators we researched tried to integrate environmental, economic, and social aspects without skewing focus to one of these three categories, policy cannot continue to regulate a single sector of society without considering impacts to the entire watershed and/or region. Unequal distribution of the water pollution burden creates disjointed economic growth, infrastructure development, and policy enactment across the sectors preventing a holistic approach to water quality management and, thus, rendering our system unsustainable.
NASA Astrophysics Data System (ADS)
Wildan, D. M.; Affandi, R.; Pratiwi, N. T. M.; Krisanti, M.; Ayu, I. P.; Iswantari, A.
2017-01-01
Vaname shrimp (Litopenaeusvannamei) is one of the excellent fishery commodities in Indonesia. Vaname shrimp farming can be conducted in low salinity water. Low salinity water sources which could be used as culture media is karst water because it has a high mineral. The research was aimedto evaluate land suitability mapping for pond as the vaname shrimpculture mediaseen from the water quality. Research was conducted in May and August 2016. Water sampling was conducted in several locations; Ancol-Jakarta (seawater), Ciseeng-Bogor (karst water salinity), Ciampea-Bogor (karst freshwater), and Situ Gede Bogor (freshwater). Evaluating the suitability of karst water quality for vaname shrimp culture media, done by the results of karst water quality analysis compared with seawater and SNI 01-7246-2006 on shrimp vaname culture media. The results showed that Karst water of Ciseeng and Ciampea could not directly use as vaname shrimp culture media. It is needed water quality treatment of ozonation and aeration of karst water to improve water quality. Ozonation and aeration treatments were able to improve the quality of karst water up to approach the living quality standard of vaname shrimp media.
Rational Exploitation and Utilizing of Groundwater in Jiangsu Coastal Area
NASA Astrophysics Data System (ADS)
Kang, B.; Lin, X.
2017-12-01
Jiangsu coastal area is located in the southeast coast of China, where is a new industrial base and an important coastal and Land Resources Development Zone of China. In the areas with strong human exploitation activities, regional groundwater evolution is obviously affected by human activities. In order to solve the environmental geological problems caused by groundwater exploitation fundamentally, we must find out the forming conditions of regional groundwater hydrodynamic field, and the impact of human activities on groundwater hydrodynamic field evolution and hydrogeochemical evolition. Based on these results, scientific management and reasonable exploitation of the regional groundwater resources can be provided for the utilization. Taking the coastal area of Jiangsu as the research area, we investigate and analyze of the regional hydrogeological conditions. The numerical simulation model of groundwater flow was established according to the water power, chemical and isotopic methods, the conditions of water flow and the influence of hydrodynamic field on the water chemical field. We predict the evolution of regional groundwater dynamics under the influence of human activities and climate change and evaluate the influence of groundwater dynamic field evolution on the environmental geological problems caused by groundwater exploitation under various conditions. We get the following conclusions: Three groundwater exploitation optimal schemes were established. The groundwater salinization was taken as the primary control condition. The substitution model was proposed to model groundwater exploitation and water level changes by BP network method.Then genetic algorithm was used to solve the optimization solution. Three groundwater exploitation optimal schemes were submit to local water resource management. The first sheme was used to solve the groundwater salinization problem. The second sheme focused on dual water supply. The third sheme concerned on emergency water supppy. This is the first time environment problem taken as water management objectinve in this coastal area.
Globalizing Lessons Learned from Regional-scale Observatories
NASA Astrophysics Data System (ADS)
Glenn, S. M.
2016-02-01
The Mid Atlantic Regional Association Coastal Ocean Observing System (MARACOOS) has accumulated a decade of experience designing, building and operating a Regional Coastal Ocean Observing System for the U.S. Integrated Ocean Observing System (IOOS). MARACOOS serves societal goals and supports scientific discovery at the scale of a Large Marine Ecosystem (LME). Societal themes include maritime safety, ecosystem decision support, coastal inundation, water quality and offshore energy. Scientific results that feed back on societal goals with better products include improved understanding of seasonal transport pathways and their impact on phytoplankton blooms and hypoxia, seasonal evolution of the subsurface Mid Atlantic Cold Pool and its impact on fisheries, biogeochemical transformations in coastal plumes, coastal ocean evolution and impact on hurricane intensities, and storm sediment transport pathways. As the global ocean observing requirements grow to support additional societal needs for information on fisheries and aquaculture, ocean acidification and deoxygenation, water quality and offshore development, global observing will necessarily evolve to include more coastal observations and forecast models at the scale of the world's many LMEs. Here we describe our efforts to share lessons learned between the observatory operators at the regional-scale of the LMEs. Current collaborators are spread across Europe, and also include Korea, Indonesia, Australia, Brazil and South Africa. Specific examples include the development of a world standard QA/QC approach for HF Radar data that will foster the sharing of data between countries, basin-scale underwater glider missions between internationally-distributed glider ports to developed a shared understanding of operations and an ongoing evaluation of the global ocean models in which the regional models for the LME will be nested, and joint training programs to develop the distributed teams of scientists and technicians required to support the global network. Globalization includes the development of international networks to coordinate activities, such as the Global HF Radar network supported by GEO, the global Everyone's Glider Organization supported by WMO and IOC, and the need for professional training supported by MTS.
TRIBAL WATER QUALITY STANDARDS WORKSHOP
Water quality standards are the foundation for water management actions. They provide the basis for regulating discharges of pollutants to surface waters, and provide a target for restoration of degraded waters. Water quality standards identify and protect uses of the water bod...
Water Quality Records in California
1964-01-01
The quality-of-water investigations of the U.S. Geological Survey are concerned with the chemical and physical characteristics of surface and ground water supplies of the Nation in conjunction with water usage and its availability. The basic records for the 1964 water year for quality of surface waters within the State of California are given in this report. For convenience and interest there are also records for a few water quality stations in bordering States. The data were collected and computed by the Water Resources Division of the U.S. Geological Survey, under the direction of Eugene Brown, district chemist, Quality of Water Branch.
Quality of waters in California
,
1963-01-01
The quality-of-water investigations of the U.S. Geological Survey are concerned with the chemical and physical characteristics of surface and ground water supplies of the nation in conjunction with water usage and its availability. The basic records for the 1963 water year for quality of surface waters within the State of California are given in this report. For convenience and interest there are also records for a few water quality stations in bordering states. The data were collected and computed by the Water Resources Division of the U.S. Geological Survey, under the direction of Eugene Brown, district chemist, Quality of Water Branch.
Zhang, Lihua; Zeng, Guangming; Dong, Haoran; Chen, Yaoning; Zhang, Jiachao; Yan, Ming; Zhu, Yuan; Yuan, Yujie; Xie, Yankai; Huang, Zhenzhen
2017-04-01
This study evaluated the influence of silver nanoparticles (AgNPs) on evolutions of organic matter and nitrogen during co-composting of sewage sludge and agricultural waste. Two co-composting piles were conducted, one was treated without AgNPs (pile 1) and the other with AgNPs (pile 2). Results showed that the AgNPs affected the quality of final composts. Less organic matter (OM) losses were determined in pile 2 (57.96%) than pile 1 (61.66%). 27.22% and 30.1% of the initial total organic matter (TOC) was decomposed in pile 1 and pile 2, respectively. The final water soluble carbon (WSC) concentration in pile 2 was 23559.27mg/kg DW compost which was significantly lower than pile 1 (25642.75mg/kg DW compost). Changes of different forms of nitrogen in the two piles showed that AgNPs could reduce the losses of TN but increase the losses of mineral N. Copyright © 2017 Elsevier Ltd. All rights reserved.
Potential impacts of changing supply-water quality on drinking water distribution: A review.
Liu, Gang; Zhang, Ya; Knibbe, Willem-Jan; Feng, Cuijie; Liu, Wentso; Medema, Gertjan; van der Meer, Walter
2017-06-01
Driven by the development of water purification technologies and water quality regulations, the use of better source water and/or upgraded water treatment processes to improve drinking water quality have become common practices worldwide. However, even though these elements lead to improved water quality, the water quality may be impacted during its distribution through piped networks due to the processes such as pipe material release, biofilm formation and detachment, accumulation and resuspension of loose deposits. Irregular changes in supply-water quality may cause physiochemical and microbiological de-stabilization of pipe material, biofilms and loose deposits in the distribution system that have been established over decades and may harbor components that cause health or esthetical issues (brown water). Even though it is clearly relevant to customers' health (e.g., recent Flint water crisis), until now, switching of supply-water quality is done without any systematic evaluation. This article reviews the contaminants that develop in the water distribution system and their characteristics, as well as the possible transition effects during the switching of treated water quality by destabilization and the release of pipe material and contaminants into the water and the subsequent risks. At the end of this article, a framework is proposed for the evaluation of potential transition effects. Copyright © 2017 Elsevier Ltd. All rights reserved.
Assessment of water quality from water harvesting using small farm reservoir for irrigation
NASA Astrophysics Data System (ADS)
Dewi, W. S.; Komariah; Samsuri, I. Y.; Senge, M.
2018-03-01
This study aims to assess the quality of rainfall-runoff water harvesting using small farm reservoir (SFR) for irrigation. Water quality assessment criteria based on RI Government Regulation number 82 the year 2001 on Water Quality Management and Pollution Control, and FAO Irrigation Water Quality Guidelines 1985. The experiment was conducted in the dry land of Wonosari Village, Gondangrejo District, Karanganyar Regency. SFR size was 10 m x 3 m x 2 m. Water quality measurements are done every week, ten times. Water samples were taken at 6 points, namely: distance of 2.5 m, 5 m, and 7.5 m from the inlet, at depth 25 cm and 175 cm from surface water. In each sampling point replicated three times. Water quality parameters include dissolved oxygen (DO), Turbidity (TSS), water pH, Nitrate (NO3), and Phosphate. The results show that water harvesting that collected in SFR meets both standards quality used, so the water is feasible for agricultural irrigation. The average value of harvested water was DO 2.6 mg/l, TSS 62.7 mg/l, pH 6.6, P 5.3 mg/l and NO3 0.16 mg/l. Rainfall-runoff water harvesting using SFR prospectus for increasing save water availability for irrigation.
9 CFR 108.11 - Water quality requirements.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Water quality requirements. 108.11... LICENSED ESTABLISHMENTS § 108.11 Water quality requirements. A certification from the appropriate water pollution control agency, that the establishment is in compliance with applicable water quality control...
9 CFR 108.11 - Water quality requirements.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Water quality requirements. 108.11... LICENSED ESTABLISHMENTS § 108.11 Water quality requirements. A certification from the appropriate water pollution control agency, that the establishment is in compliance with applicable water quality control...
DESCRIPTIVE WATER QUALITY FOR THE ATCHAFALAYA BASIN, LOUISIANA
This report describes water quality in the Atchafalaya Basin in terms of geographical areas, seasonal patterns, and its relationships to water regimes and compares water quality in the Basin to water quality in other Louisiana and southeastern lakes. Emphasis in this report is gi...
9 CFR 108.11 - Water quality requirements.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Water quality requirements. 108.11... LICENSED ESTABLISHMENTS § 108.11 Water quality requirements. A certification from the appropriate water pollution control agency, that the establishment is in compliance with applicable water quality control...
NASA Astrophysics Data System (ADS)
Guzmán, Gema; Giráldez, Juan Vicente; Gómez, José Alfonso
2014-05-01
Numerous studies have attempted to assess the differences in soil properties caused by different management systems in olive cropped farms. Nevertheless the influence of the most frequent management systems on the hydraulic properties of these soils has not been evaluated. Contrarily, there are very few studies that have tried to correlate these results with soil losses due to water erosion. There are complementary approaches to traditional degradation indices, as the S index based on the form of the soil retention curve (Dexter 2004a,b,c). The objectives of this study were (i) to evaluate the methods based on the S index to assess the physical quality of soil in olive orchards, (ii) to assess the short-term changes (2 years) in soil physical and chemical properties in two olive orchards under different managements systems, namely conventional tillage and cover crop, and (iii) to formulate strategies for assessing the quality of soil in olive orchards. For the studied soils, degradation processes (associated to conventional tillage) and the improvement of their properties (linked to cover crops) showed a fast response. Chemical changes were quickly observed. However physical changes are slower than chemical changes for both soils. Water retention curves allowed the evaluation of soil porosity based on depth in the profile and the management practices. The S index was computed for every soil using the conventional soil water retention equations fitted to the experimental data. For the olive cropped soils, higher S index values were obtained in the less degradated areas, in most of the cases. Therefore, the S index could be used as a soil quality indicator although further research should be required to study its evolution at a larger temporal scale. References: Dexter, A. R. 2004. a.- Soil physical quality. PartI. Theory, effects of soil texture, density, and organic matter, and effects on root growth. Geoderma 120 (2004) 201-214. Dexter, A. R. 2004. b.- Soil physical quality. Part II. Friability, tillage, tilth and hardsetting. Geoderma 120 (2004) 215-225. Dexter, A. R. 2004. c.- Soil physical quality. Part III: Unsaturated hydraulic conductivity and general conclusions about S-theory. Geoderma 120 (2004) 227-239.
The Effect of Ambient Water Quality on Lakefront Property Values: Evidence from Coeur d'Alene, Idaho
NASA Astrophysics Data System (ADS)
Liao, H.
2015-12-01
Climate warming is causing water temperatures to increase and subsequent changes in water quality. To develop innovative approaches for mitigating the possible negative social consequences of such changes, more research efforts are needed to investigate how people perceive and respond to ambient water quality. This research examines the amenity value of water quality in the areas centered on Lake Coeur d'Alene of Northern Idaho. Through a hedonic analysis, we find that two important water-quality variables have had significant effects on lakefront property values, including Secchi disc reading, a technical measure of water clarity, and the presence of Eurasian watermilfoil, an aquatic invasive species. We further explore the spatial heterogeneity of water-quality benefits along the urban-rural gradient and find that access to urban amenities has strengthened the water-quality benefits in the lakefront housing market. Our findings could be used to incentivize private property owners and stakeholders to commit time and funding to cope with the potential degradation of water quality under climate change.
Landon, M.K.; Delin, G.N.; Nelson, K.J.; Regan, C.P.; Lamb, J.A.; Larson, S.J.; Capel, P.D.; Anderson, J.L.; Dowdy, R.H.
1997-01-01
The Minnesota Management Systems Evaluation Area (MSEA) project was part of a multi-scale, inter-agency initiative to evaluate the effects of agricultural management systems on water quality in the midwest corn belt. The research area was located in the Anoka Sand Plain about 5 kilometers southwest of Princeton, Minnesota. The ground-water-quality monitoring network within and immediately surrounding the research area consisted of 73 observation wells and 25 multiport wells. The primary objectives of the ground-water monitoring program at the Minnesota MSEA were to: (1) determine the effects of three farming systems on ground-water quality, and (2) understand the processes and factors affecting the loading, transport, and fate of agricultural chemicals in ground water at the site. This report presents well construction, geologic, water-level, chemical application, water-quality, and quality-assurance data used to evaluate the effects of farming systems on ground-water quality during 1991-95.
The maladies of water and war: addressing poor water quality in Iraq.
Zolnikov, Tara Rava
2013-06-01
Water is essential in providing nutrients, but contaminated water contributes to poor population health. Water quality and availability can change in unstructured situations, such as war. To develop a practical strategy to address poor water quality resulting from intermittent wars in Iraq, I reviewed information from academic sources regarding waterborne diseases, conflict and war, water quality treatment, and malnutrition. The prevalence of disease was high in impoverished, malnourished populations exposed to contaminated water sources. The data aided in developing a strategy to improve water quality in Iraq, which encompasses remineralized water from desalination plants, health care reform, monitoring and evaluation systems, and educational public health interventions.
Gurdak, Jason J.; McMahon, Peter B.; Dennehy, Kevin; Qi, Sharon L.
2009-01-01
This report contains the major findings of a 1999-2004 assessment of water quality in the High Plains aquifer. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings for principal and other aquifers and major river basins across the Nation. In these reports, water quality is discussed in terms of local, regional, State, and national issues. Conditions in the aquifer system are compared to conditions found elsewhere and to selected national benchmarks, such as those for drinking-water quality. This report is intended for individuals working with water-resource issues in Federal, State, or local agencies, universities, public interest groups, or the private sector. The information will be useful in addressing a number of current issues, such as drinking-water quality, the effects of agricultural practices on water quality, source-water protection, and monitoring and sampling strategies. This report is also for individuals who wish to know more about the quality of ground water in areas near where they live and how that water quality compares to the quality of water in other areas across the region and the Nation. The water-quality conditions in the High Plains aquifer summarized in this report are discussed in greater detail in other reports that can be accessed in Appendix 1 of http://pubs.usgs.gov/pp/1749/. Detailed technical information, data and analyses, collection and analytical methodology, models, graphs, and maps that support the findings presented in this report in addition to reports in this series from other basins can be accessed from the national NAWQA Web site (http://water.usgs.gov/nawqa). This report accompanies the detailed and technical report of water-quality conditions in the High Plains aquifer 'Water-quality assessment of the High Plains aquifer, 1999-2004' (http://pubs.usgs.gov/pp/1749/)
Wicklein, Shaun M.; Powell, Eugene D.; Guyer, Joel R.; Owens, Joseph A.
2006-01-01
Water-resources data for the 2005 water year for Virginia consist of records of water levels and water quality of ground-water wells. This report (Volume 2. Ground-Water-Level and Ground-Water-Quality Records) contains water levels at 349 observation wells and water quality at 29 wells. Locations of these wells are shown on figures 3 through 8. The data in this report represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Virginia.
Results of high heat flux qualification tests of W monoblock components for WEST
NASA Astrophysics Data System (ADS)
Greuner, H.; Böswirth, B.; Lipa, M.; Missirlian, M.; Richou, M.
2017-12-01
One goal of the WEST project (W Environment in Steady-state Tokamak) is the manufacturing, quality assessment and operation of ITER-like actively water-cooled divertor plasma facing components made of tungsten. Six W monoblock plasma facing units (PFUs) from different suppliers have been successfully evaluated in the high heat flux test facility GLADIS at IPP. Each PFU is equipped with 35 W monoblocks of an ITER-like geometry. However, the W blocks are made of different tungsten grades and the suppliers applied different bonding techniques between tungsten and the inserted Cu-alloy cooling tubes. The intention of the HHF test campaign was to assess the manufacturing quality of the PFUs on the basis of a statistical analysis of the surface temperature evolution of the individual W monoblocks during thermal loading with 100 cycles at 10 MW m-2. These tests confirm the non-destructive examinations performed by the manufacturer and CEA prior to the installation of the WEST platform, and no defects of the components were detected.
Cristiglio, Viviana; Grillo, Isabelle; Fomina, Margarita; Wien, Frank; Shalaev, Evgenyi; Novikov, Alexey; Brassamin, Séverine; Réfrégiers, Matthieu; Pérez, Javier; Hennet, Louis
2017-01-01
The acoustic levitation technique is a useful sample handling method for small solid and liquids samples, suspended in air by means of an ultrasonic field. This method was previously used at synchrotron sources for studying pharmaceutical liquids and protein solutions using x-ray diffraction and small angle x-ray scattering (SAXS). In this work we combined for the first time this containerless method with small angle neutron scattering (SANS) and synchrotron radiation circular dichroism (SRCD) to study the structural behavior of proteins in solutions during the water evaporation. SANS results are also compared with SAXS experiments. The aggregation behavior of 45μl droplets of lysozyme protein diluted in water was followed during the continuous increase of the sample concentration by evaporating the solvent. The evaporation kinetics was followed at different drying stage by SANS and SAXS with a good data quality. In a prospective work using SRCD, we also studied the evolution of the secondary structure of the myoglobin protein in water solution in the same evaporation conditions. Acoustic levitation was applied for the first time with SANS and the high performances of the used neutron instruments made it possible to monitor fast container-less reactions in situ. A preliminary work using SRCD shows the potentiality of its combination with acoustic levitation for studying the evolution of the protein structure with time. This multi-techniques approach could give novel insights into crystallization and self-assembly phenomena of biological compound with promising potential applications in pharmaceutical, food and cosmetics industry. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo. Copyright © 2016 Elsevier B.V. All rights reserved.
Code of Federal Regulations, 2010 CFR
2010-01-01
... portion of the 208 water-quality management plan. (s) OMB Circular A-34. “Instructions on Budget Execution... needed to attain water quality standards or water quality goals. Fifty (50) percent of the adequate level... agency. A soil conservation district, State soil and water conservation agency, or State water quality...
Code of Federal Regulations, 2011 CFR
2011-01-01
... portion of the 208 water-quality management plan. (s) OMB Circular A-34. “Instructions on Budget Execution... needed to attain water quality standards or water quality goals. Fifty (50) percent of the adequate level... agency. A soil conservation district, State soil and water conservation agency, or State water quality...
40 CFR 130.8 - Water quality report.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 23 2013-07-01 2013-07-01 false Water quality report. 130.8 Section 130.8 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.8 Water quality report. (a) Each State shall prepare and submit...
40 CFR 130.4 - Water quality monitoring.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 22 2014-07-01 2013-07-01 true Water quality monitoring. 130.4 Section 130.4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.4 Water quality monitoring. (a) In accordance with section 106(e)(1...
40 CFR 130.4 - Water quality monitoring.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 23 2012-07-01 2012-07-01 false Water quality monitoring. 130.4 Section 130.4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.4 Water quality monitoring. (a) In accordance with section 106(e)(1...
40 CFR 130.8 - Water quality report.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 23 2012-07-01 2012-07-01 false Water quality report. 130.8 Section 130.8 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.8 Water quality report. (a) Each State shall prepare and submit...
40 CFR 130.4 - Water quality monitoring.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 23 2013-07-01 2013-07-01 false Water quality monitoring. 130.4 Section 130.4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.4 Water quality monitoring. (a) In accordance with section 106(e)(1...
40 CFR 130.8 - Water quality report.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 22 2011-07-01 2011-07-01 false Water quality report. 130.8 Section 130.8 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.8 Water quality report. (a) Each State shall prepare and submit...
Global water cycle and the coevolution of the Earth's interior and surface environment.
Korenaga, Jun; Planavsky, Noah J; Evans, David A D
2017-05-28
The bulk Earth composition contains probably less than 0.3% of water, but this trace amount of water can affect the long-term evolution of the Earth in a number of different ways. The foremost issue is the occurrence of plate tectonics, which governs almost all aspects of the Earth system, and the presence of water could either promote or hinder the operation of plate tectonics, depending on where water resides. The global water cycle, which circulates surface water into the deep mantle and back to the surface again, could thus have played a critical role in the Earth's history. In this contribution, we first review the present-day water cycle and discuss its uncertainty as well as its secular variation. If the continental freeboard has been roughly constant since the Early Proterozoic, model results suggest long-term net water influx from the surface to the mantle, which is estimated to be 3-4.5×10 14 g yr -1 on the billion years time scale. We survey geological and geochemical observations relevant to the emergence of continents above the sea level as well as the nature of Precambrian plate tectonics. The global water cycle is suggested to have been dominated by regassing, and its implications for geochemical cycles and atmospheric evolution are also discussed.This article is part of the themed issue 'The origin, history and role of water in the evolution of the inner Solar System'. © 2017 The Author(s).
Global water cycle and the coevolution of the Earth’s interior and surface environment
Planavsky, Noah J.; Evans, David A. D.
2017-01-01
The bulk Earth composition contains probably less than 0.3% of water, but this trace amount of water can affect the long-term evolution of the Earth in a number of different ways. The foremost issue is the occurrence of plate tectonics, which governs almost all aspects of the Earth system, and the presence of water could either promote or hinder the operation of plate tectonics, depending on where water resides. The global water cycle, which circulates surface water into the deep mantle and back to the surface again, could thus have played a critical role in the Earth’s history. In this contribution, we first review the present-day water cycle and discuss its uncertainty as well as its secular variation. If the continental freeboard has been roughly constant since the Early Proterozoic, model results suggest long-term net water influx from the surface to the mantle, which is estimated to be 3−4.5×1014 g yr−1 on the billion years time scale. We survey geological and geochemical observations relevant to the emergence of continents above the sea level as well as the nature of Precambrian plate tectonics. The global water cycle is suggested to have been dominated by regassing, and its implications for geochemical cycles and atmospheric evolution are also discussed. This article is part of the themed issue ‘The origin, history and role of water in the evolution of the inner Solar System’. PMID:28416728
Moreland, Joe A.; Wood, Wayne A.
1982-01-01
Water-level and water-quality data were collected from monitoring wells at wastewater-treatment facilities in Glacier National Park. Five additional shallow observation wells were installed at the Glacier Park Headquarters facility to monitor water quality in the shallow ground-water system.Water-level, water-quality, and geologic information indicate that some of the initial monitoring wells are not ideally located to sample ground water most likely to be affected by waste disposal at the sites. Small differences in chemical characteristics between samples from monitor wells indicate that effluent may be affecting ground-water quality but that impacts are not significant.Future monitoring of ground-water quality could be limited to selected wells most likely to be impacted by percolating effluent. Laboratory analyses for common ions could detect future impacts.
Drinking water quality management: a holistic approach.
Rizak, S; Cunliffe, D; Sinclair, M; Vulcano, R; Howard, J; Hrudey, S; Callan, P
2003-01-01
A growing list of water contaminants has led to some water suppliers relying primarily on compliance monitoring as a mechanism for managing drinking water quality. While such monitoring is a necessary part of drinking water quality management, experiences with waterborne disease threats and outbreaks have shown that compliance monitoring for numerical limits is not, in itself, sufficient to guarantee the safety and quality of drinking water supplies. To address these issues, the Australian National Health and Medical Research Council (NHMRC) has developed a Framework for Management of Drinking Water Quality (the Framework) for incorporation in the Australian Drinking Water Guidelines, the primary reference on drinking water quality in Australia. The Framework was developed specifically for drinking water supplies and provides a comprehensive and preventive risk management approach from catchment to consumer. It includes holistic guidance on a range of issues considered good practice for system management. The Framework addresses four key areas: Commitment to Drinking Water Quality Management, System Analysis and System Management, Supporting Requirements, and Review. The Framework represents a significantly enhanced approach to the management and regulation of drinking water quality and offers a flexible and proactive means of optimising drinking water quality and protecting public health. Rather than the primary reliance on compliance monitoring, the Framework emphasises prevention, the importance of risk assessment, maintaining the integrity of water supply systems and application of multiple barriers to assure protection of public health. Development of the Framework was undertaken in collaboration with the water industry, regulators and other stakeholder, and will promote a common and unified approach to drinking water quality management throughout Australia. The Framework has attracted international interest.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-13
... Activities: Proposed Collection; Comment Request; National Water Quality Inventory Reports (Renewal) AGENCY... Clean Water Act (CWA) responsibilities. Title: National Water Quality Inventory Reports (Clean Water Act... information on the water quality standards attainment status of assessed waters, and, when waters are impaired...
Use of tolerance values to diagnose water-quality stressors to aquatic biota in New England streams
Meador, M.R.; Carlisle, D.M.; Coles, J.F.
2008-01-01
Identification of stressors related to biological impairment is critical to biological assessments. We applied nationally derived tolerance indicator values for four water-quality variables to fish and benthic macroinvertebrate assemblages at 29 sites along an urban gradient in New England. Tolerance indicator values (TIVs), as biologically based predictors of water-quality variables, were determined for dissolved oxygen, nitrite plus nitrate (nitrate), total phosphorus, and water temperature for each site based on observed biological assemblages (TIVO), and for expected assemblages (TIVE). The quotient method, based on a ratio of the TIVs for observed and expected assemblages (tolerance units), was used to diagnose potential water-quality stressors. In addition, the ratio of measured water-quality values to water-quality criteria (water-quality units) was calculated for each water-quality variable to assess measured water-quality stressors. Results from a RIVPACS predictive model for benthic macroinvertebrates and Bray-Curtis dissimilarity for fish were used to classify sites into categories of good or impaired ecological condition. Significant differences were detected between good and impaired sites for all biological tolerance units (fish and benthic macroinvertebrate assemblages averaged) except for nitrate (P = 0.480), and for all water-quality units except for nitrate (P = 0.183). Diagnosis of water-quality stressors at selected sites was, in general, consistent with State-reported causes of impairment. Tolerance units for benthic macroinvertebrate and fish assemblages were significantly correlated for water temperature (P = 0.001, r = 0.63), dissolved oxygen (P = 0.001, r = 0.61), and total phosphorus (P = 0.001, r = 0.61), but not for nitrate (P = 0.059, r = -0.35). Differences between the two assemblages in site-specific diagnosis of water-quality stressors may be the result of differences in nitrate tolerance.
NASA Astrophysics Data System (ADS)
Sperotto, Anna; Torresan, Silvia; Molina, Jose Luis; Pulido Velazquez, Manuel; Critto, Andrea; Marcomini, Antonio
2017-04-01
Understanding the co-evolution and interrelations between natural and human pressures on water systems is required to ensure a sustainable management of resources under uncertain climate change conditions. To pursue multi-disciplinary research is therefore necessary to consider the multiplicity of stressors affecting water resources, take into account alternative perspectives (i.e. social, economic and environmental objective and priorities) and deal with uncertainty which characterize climate change scenarios. However, approaches commonly adopted in water quality assessment are predominantly mono-disciplinary, single-stressors oriented and apply concepts and models specific of different academic disciplines (e.g. physics, hydrology, ecology, sociology, economy) which, in fact, seldom shed their conceptual blinders failing to provide truly integrated results. In this context, the paper discusses the benefits and limits of adopting a multi-disciplinary approach where different knowledge domains collaborate and quantitative and qualitative information, coming from multiple conceptual and model-based research, are integrated in a harmonic manner. Specifically, Bayesian Networks are used as meta-modelling tool for structuring and combining the probabilistic information available in existing hydrological models, climate change and land use projections, historical observations and expert opinion. The developed network allows to perform a stochastic multi-risk assessment considering the interlacing between climate (i.e. irregularities in water regime) and land use changes (i.e. agriculture, urbanization) and their cascading impacts on water quality parameters (i.e. nutrients loadings). Main objective of the model is the development of multi-risk scenarios to assess and communicate the probability of not meeting a "Good chemical water status" over future timeframe taking into account projected climatic and not climatic conditions. The outcomes are finally used to identify tradeoffs between different water uses and perspectives, thus promoting the implementation of best practices for adaptation and management with ancillary co-benefits and cross-sectoral implications (i.e. tourism, fishing, biodiversity). Some preliminary results, describing the application of the model in the Dese-Zero river estuary, one of the main tributaries of the Venice Lagoon in Italy, will be here presented and discussed.
Water Quality in the Delmarva Peninsula, Delaware, Maryland, and Virginia, 1999-2001
Denver, Judith M.; Ator, Scott W.; Debrewer, Linda M.; Ferrari, Matthew J.; Barbaro, Jeffrey R.; Hancock, Tracy C.; Brayton, Michael J.; Nardi, Mark R.
2004-01-01
This report contains the major findings of a 1999-2001 assessment of water quality in the Delmarva Peninsula. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is assessed at many scales?from local ground-water flow paths to regional ground-water networks and in surface water?and is discussed in terms of local, State, and regional issues. Conditions in the Delmarva Peninsula are compared to conditions found elsewhere and to selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. This report is intended for individuals working with water-resource issues in Federal, State, or local agencies; universities; public interest groups; or in the private sector. The information will be useful in addressing a number of current issues, such as the effects of agricultural and urban land use on water quality, human health, drinking water, source-water protection, hypoxia and excessive growth of algae and plants, pesticide registration, and monitoring and sampling strategies. This report is also for individuals who wish to know more about the quality of streams and ground water in areas near where they live, and how that water quality compares to the quality of water in other areas across the Nation. Other products describing water-quality conditions in the Delmarva Peninsula are available. Detailed technical information, data and analyses, methodology, models, graphs, and maps that support the findings presented in this report can be accessed from http://md.water.usgs.gov/delmarva. Other reports in this series and data collected from other basins can be accessed from the national NAWQA Web site (http://water.usgs.gov/nawqa).
USDA-ARS?s Scientific Manuscript database
Agricultural research continually seeks to increase productivity while protecting soil, water and genetic resources. The book Darwinian Agriculture: How Understanding Evolution Can Improve Agriculture, by R. Ford Dennison, delivers a thought-provoking view of how principles of ecology and evolution ...
Deriving Chesapeake Bay Water Quality Standards
Tango, Peter J.; Batiuk, Richard A.
2013-01-01
Achieving and maintaining the water quality conditions necessary to protect the aquatic living resources of the Chesapeake Bay and its tidal tributaries has required a foundation of quantifiable water quality criteria. Quantitative criteria serve as a critical basis for assessing the attainment of designated uses and measuring progress toward meeting water quality goals of the Chesapeake Bay Program partnership. In 1987, the Chesapeake Bay Program partnership committed to defining the water quality conditions necessary to protect aquatic living resources. Under section 303(c) of the Clean Water Act, States and authorized tribes have the primary responsibility for adopting water quality standards into law or regulation. The Chesapeake Bay Program partnership worked with U.S. Environmental Protection Agency to develop and publish a guidance framework of ambient water quality criteria with designated uses and assessment procedures for dissolved oxygen, water clarity, and chlorophyll a for Chesapeake Bay and its tidal tributaries in 2003. This article reviews the derivation of the water quality criteria, criteria assessment protocols, designated use boundaries, and their refinements published in six addendum documents since 2003 and successfully adopted into each jurisdiction's water quality standards used in developing the Chesapeake Bay Total Maximum Daily Load.
NASA Astrophysics Data System (ADS)
Roy, P. K.; Pal, S.; Banerjee, G.; Biswas Roy, M.; Ray, D.; Majumder, A.
2014-12-01
River is considered as one of the main sources of freshwater all over the world. Hence analysis and maintenance of this water resource is globally considered a matter of major concern. This paper deals with the assessment of surface water quality of the Ichamati river using multivariate statistical techniques. Eight distinct surface water quality observation stations were located and samples were collected. For the samples collected statistical techniques were applied to the physico-chemical parameters and depth of siltation. In this paper cluster analysis is done to determine the relations between surface water quality and siltation depth of river Ichamati. Multiple regressions and mathematical equation modeling have been done to characterize surface water quality of Ichamati river on the basis of physico-chemical parameters. It was found that surface water quality of the downstream river was different from the water quality of the upstream. The analysis of the water quality parameters of the Ichamati river clearly indicate high pollution load on the river water which can be accounted to agricultural discharge, tidal effect and soil erosion. The results further reveal that with the increase in depth of siltation, water quality degraded.
Real-time water quality monitoring and providing water quality ...
EPA and the U.S. Geological Survey (USGS) have initiated the “Village Blue” research project to provide real-time water quality monitoring data to the Baltimore community and increase public awareness about local water quality in Baltimore Harbor and the Chesapeake Bay. The Village Blue demonstration project complements work that a number of state and local organizations are doing to make Baltimore Harbor “swimmable and fishable” 2 by 2020. Village Blue is designed to build upon EPA’s “Village Green” project which provides real-time air quality information to communities in six locations across the country. The presentation, “Real-time water quality monitoring and providing water quality information to the Baltimore Community”, summarizes the Village Blue real-time water quality monitoring project being developed for the Baltimore Harbor.
Analysis of trends in water-quality data for water conservation area 3A, the Everglades, Florida
Mattraw, H.C.; Scheidt, D.J.; Federico, A.C.
1987-01-01
Rainfall and water quality data bases from the South Florida Water Management District were used to evaluate water quality trends at 10 locations near or in Water Conservation Area 3A in The Everglades. The Seasonal Kendall test was applied to specific conductance, orthophosphate-phosphorus, nitrate-nitrogen, total Kjeldahl nitrogen, and total nitrogen regression residuals for the period 1978-82. Residuals of orthophosphate and nitrate quadratic models, based on antecedent 7-day rainfall at inflow gate S-11B, were the only two constituent-structure pairs that showed apparent significant (p < 0.05) increases in constituent concentrations. Elimination of regression models with distinct residual patterns and data outlines resulted in 17 statistically significant station water quality combinations for trend analysis. No water quality trends were observed. The 1979 Memorandum of Agreement outlining the water quality monitoring program between the Everglades National Park and the U.S. Army Corps of Engineers stressed collection four times a year at three stations, and extensive coverage of water quality properties. Trend analysis and other rigorous statistical evaluation programs are better suited to data monitoring programs that include more frequent sampling and that are organized in a water quality data management system. Pronounced areal differences in water quality suggest that a water quality monitoring system for Shark River Slough in Everglades National Park include collection locations near the source of inflow to Water Conservation Area 3A. (Author 's abstract)
NASA Astrophysics Data System (ADS)
Bhutiani, R.; Khanna, D. R.; Kulkarni, Dipali Bhaskar; Ruhela, Mukesh
2016-06-01
The river Ganges is regarded as one of the most holy and sacred rivers of the world from time immemorial. The evaluation of river water quality is a critical element in the assessment of water resources. The quality/potability of water that is consumed defines the base line of protection against many diseases and infections. The present study aimed to calculate Water Quality Index (WQI) by the analysis of sixteen physico-chemical parameters on the basis of River Ganga index of Ved Prakash, weighted arithmetic index and WQI by National sanitation foundation (NSF) to assess the suitability of water for drinking, irrigation purposes and other human uses. These three water quality indices have been used to assess variation in the quality of the River Ganga at monitored locations over an 11-year period. Application of three different indexes to assess the water quality over a period of 11 years shows minor variations in water quality. Index values as per River Ganga Index by Ved Prakash et al. from 2000 to 2010 ranged between medium to good, Index values as per NSF Index for years 2000-2010 indicate good water quality, while Index values as per the weighted arithmetic index method for the study period indicate poor water quality.
Quality of surface water in the Suwannee River Basin, Florida, August 1968 through December 1977
Hull, Robert W.; Dysart, Joel E.; Mann, William B.
1981-01-01
In the 9,950-square mile area of the Suwannee River basin in Florida and Georgia, 17 surface-water stations on 9 streams and several springs were sampled for selected water-quality properties and constituents from August 1968 through December 1977. Analyses from these samples indicate that: (1) the water quality of tributary wetlands controls the water quality of the upper Suwannee River headwaters; (2) groundwater substantially affects the water quality of the Suwannee River basin streams below these headquarters; (3) the water quality of the Suwannee River, and many of its tributaries, is determined by several factors and is not simply related to discharge; and (4) development in the Suwannee River basin has had observable effects on the quality of surface waters.
Baum, Rachel; Kayser, Georgia; Stauber, Christine; Sobsey, Mark
2014-01-01
Millennium Development Goal Target 7c (to halve between 1990 and 2015 the proportion of the global population without sustainable access to safe drinking water), was celebrated as achieved in 2012. However, new studies show that we may be prematurely celebrating. Access to safe drinking water may be overestimated if microbial water quality is considered. The objective of this study was to examine the relationship between microbial drinking water quality and drinking water source in the Puerto Plata region of the Dominican Republic. This study analyzed microbial drinking water quality data from 409 households in 33 communities. Results showed that 47% of improved drinking water sources were of high to very-high risk water quality, and therefore unsafe for drinking. This study provides evidence that the current estimate of safe water access may be overly optimistic, and microbial water quality data are needed to reliably assess the safety of drinking water.
Baum, Rachel; Kayser, Georgia; Stauber, Christine; Sobsey, Mark
2014-01-01
Millennium Development Goal Target 7c (to halve between 1990 and 2015 the proportion of the global population without sustainable access to safe drinking water), was celebrated as achieved in 2012. However, new studies show that we may be prematurely celebrating. Access to safe drinking water may be overestimated if microbial water quality is considered. The objective of this study was to examine the relationship between microbial drinking water quality and drinking water source in the Puerto Plata region of the Dominican Republic. This study analyzed microbial drinking water quality data from 409 households in 33 communities. Results showed that 47% of improved drinking water sources were of high to very-high risk water quality, and therefore unsafe for drinking. This study provides evidence that the current estimate of safe water access may be overly optimistic, and microbial water quality data are needed to reliably assess the safety of drinking water. PMID:24218411
Influence of water quality on the embodied energy of drinking water treatment.
Santana, Mark V E; Zhang, Qiong; Mihelcic, James R
2014-01-01
Urban water treatment plants rely on energy intensive processes to provide safe, reliable water to users. Changes in influent water quality may alter the operation of a water treatment plant and its associated energy use or embodied energy. Therefore the objective of this study is to estimate the effect of influent water quality on the operational embodied energy of drinking water, using the city of Tampa, Florida as a case study. Water quality and water treatment data were obtained from the David L Tippin Water Treatment Facility (Tippin WTF). Life cycle energy analysis (LCEA) was conducted to calculate treatment chemical embodied energy values. Statistical methods including Pearson's correlation, linear regression, and relative importance were used to determine the influence of water quality on treatment plant operation and subsequently, embodied energy. Results showed that influent water quality was responsible for about 14.5% of the total operational embodied energy, mainly due to changes in treatment chemical dosages. The method used in this study can be applied to other urban drinking water contexts to determine if drinking water source quality control or modification of treatment processes will significantly minimize drinking water treatment embodied energy.
Hamm, V; Collon-Drouaillet, P; Fabriol, R
2008-02-19
The flooding of abandoned mines in the Lorraine Iron Basin (LIB) over the past 25 years has degraded the quality of the groundwater tapped for drinking water. High concentrations of dissolved sulphate have made the water unsuitable for human consumption. This problematic issue has led to the development of numerical tools to support water-resource management in mining contexts. Here we examine two modelling approaches using different numerical tools that we tested on the Saizerais flooded iron-ore mine (Lorraine, France). A first approach considers the Saizerais Mine as a network of two chemical reactors (NCR). The second approach is based on a physically distributed pipe network model (PNM) built with EPANET 2 software. This approach considers the mine as a network of pipes defined by their geometric and chemical parameters. Each reactor in the NCR model includes a detailed chemical model built to simulate quality evolution in the flooded mine water. However, in order to obtain a robust PNM, we simplified the detailed chemical model into a specific sulphate dissolution-precipitation model that is included as sulphate source/sink in both a NCR model and a pipe network model. Both the NCR model and the PNM, based on different numerical techniques, give good post-calibration agreement between the simulated and measured sulphate concentrations in the drinking-water well and overflow drift. The NCR model incorporating the detailed chemical model is useful when a detailed chemical behaviour at the overflow is needed. The PNM incorporating the simplified sulphate dissolution-precipitation model provides better information of the physics controlling the effect of flow and low flow zones, and the time of solid sulphate removal whereas the NCR model will underestimate clean-up time due to the complete mixing assumption. In conclusion, the detailed NCR model will give a first assessment of chemical processes at overflow, and in a second time, the PNM model will provide more detailed information on flow and chemical behaviour (dissolved sulphate concentrations, remaining mass of solid sulphate) in the network. Nevertheless, both modelling methods require hydrological and chemical parameters (recharge flow rate, outflows, volume of mine voids, mass of solids, kinetic constants of the dissolution-precipitation reactions), which are commonly not available for a mine and therefore call for calibration data.
40 CFR 130.4 - Water quality monitoring.
Code of Federal Regulations, 2010 CFR
2010-07-01
... QUALITY PLANNING AND MANAGEMENT § 130.4 Water quality monitoring. (a) In accordance with section 106(e)(1...; developing and reviewing water quality standards, total maximum daily loads, wasteload allocations and load... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Water quality monitoring. 130.4...
78 FR 52192 - Final Aquatic Life Ambient Water Quality Criteria For Ammonia-Freshwater 2013
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-22
... ambient water quality criteria for the protection of aquatic life from effects of ammonia in freshwater... life criteria are developed based on EPA's Guidelines for Deriving Numerical National Water Quality... quality standards for protecting aquatic life and human health. EPA's recommended water quality criteria...
40 CFR 130.4 - Water quality monitoring.
Code of Federal Regulations, 2011 CFR
2011-07-01
... QUALITY PLANNING AND MANAGEMENT § 130.4 Water quality monitoring. (a) In accordance with section 106(e)(1...; developing and reviewing water quality standards, total maximum daily loads, wasteload allocations and load... 40 Protection of Environment 22 2011-07-01 2011-07-01 false Water quality monitoring. 130.4...
Investigation of Possible Wellbore Cement Failures During Hydraulic Fracturing Operations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Jihoon; Moridis, George
2014-11-01
We model and assess the possibility of shear failure, using the Mohr-Coulomb model ? along the vertical well by employing a rigorous coupled flow-geomechanic analysis. To this end, we vary the values of cohesion between the well casing and the surrounding cement to representing different quality levels of the cementing operation (low cohesion corresponds to low-quality cement and/or incomplete cementing). The simulation results show that there is very little fracturing when the cement is of high quality.. Conversely, incomplete cementing and/or weak cement can causes significant shear failure and the evolution of long fractures/cracks along the vertical well. Specifically, lowmore » cohesion between the well and cemented areas can cause significant shear failure along the well, but the same cohesion as the cemented zone does not cause shear failure. When the hydraulic fracturing pressure is high, low cohesion of the cement can causes fast propagation of shear failure and of the resulting fracture/crack, but a high-quality cement with no weak zones exhibits limited shear failure that is concentrated near the bottom of the vertical part of the well. Thus, high-quality cement and complete cementing along the vertical well appears to be the strongest protection against shear failure of the wellbore cement and, consequently, against contamination hazards to drinking water aquifers during hydraulic fracturing operations.« less
NASA Astrophysics Data System (ADS)
Ortiz, D.; Anera, R. G.; Saiz, J. M.; Jiménez, J. R.; Moreno, F.; Jiménez Del Barco, L.; González, F.
2006-11-01
This study focuses on the changes induced in both the asphericity and homogeneity of the cornea for a group of myopic eyes undergoing LASIK surgery. Eyes were characterized by a Kooijman-based customized eye model in which changes were introduced in the form of Gaussian-distributed refractive-index variations of given correlation length for the inhomogeneities and in the form of an expression, based on the modified Munnerlyn's paraxial formula, for the post-LASIK asphericity. Visual quality was evaluated in terms of the Modulation Transfer Function and the Point-Spread Function. The results show that, on average, the evolution of visual acuity is consistent with the change in corneal asphericity, while the evolution of contrast sensitivity requires a loss in corneal homogeneity in order to be explained. By including both effects in the model, the overall model performance in predicting visual quality is improved.
Improvements to quality of needle coke by controlled carbonized conditions
NASA Astrophysics Data System (ADS)
Liu, Dong; Lou, Bin; Yu, Ran; Chen, Qingtai; Li, Zhiheng; Zhang, Yadong
2018-06-01
In this study, the selected aromatic-rich fraction derived from hydrocracking tail oil was carbonized and further improvement in the quality of resultant coke was achieved by promoting temperature at the solidification stage. In comparison with conventional process carried out isothermally and isobarically, the coupling analysis between formation and subsequent uni-axial orientation of mesophase textures during the controlled process was systematically discussed on the basis of the mutual relevance among mesophase texture evolution, gas evolution rate and solidification rate of intermediates. The results show that on the premise that formation of bulk mesophase, appropriate rate of gas evolution at a right time of solidification contributes to fine produces fine fibrous mesophase aligned uni-axially and less pores. Moreover, the intermediates with solidification index of 2˜6 are suitable for deformation induced by gas evolution.
NASA Astrophysics Data System (ADS)
Alameddine, Ibrahim; Jawhari, Gheeda; El-Fadel, Mutasem
2017-04-01
Perceptions developed by consumers regarding the quality of water reaching their household can affect the ultimate use of the water. This study identified key factors influencing consumers' perception of water quality in a highly urbanized coastal city, experiencing chronic water shortages, overexploitation of groundwater, and accelerated saltwater intrusion. Household surveys were administered to residents to capture views and perceptions of consumed water. Concomitantly, groundwater and tap water samples were collected and analyzed at each residence for comparison with perceptions. People's rating of groundwater quality was found to correlate to the measured water quality both in the dry and wet seasons. In contrast, perceptions regarding the water quality of the public water supply network did not show any correlation with the measured tap water quality indicators. Logistic regression models developed to predict perception based on salient variables indicated that age, apartment ownership, and levels of total dissolved solids play a significant role in shaping perceptions regarding groundwater quality. Perceptions concerning the water quality of the public water supply network appeared to be independent of the measured total dissolved solids levels at the tap but correlated to those measured in the wells. The study highlights misconceptions that can arise as a result of uncontrolled cross-connections of groundwater to the public supply network water and the development of misaligned perceptions based on prior consumption patterns, water shortages, and a rapidly salinizing groundwater aquifer.
Gu, Qing; Deng, Jinsong; Wang, Ke; Lin, Yi; Li, Jun; Gan, Muye; Ma, Ligang; Hong, Yang
2014-01-01
Various reservoirs have been serving as the most important drinking water sources in Zhejiang Province, China, due to the uneven distribution of precipitation and severe river pollution. Unfortunately, rapid urbanization and industrialization have been continuously challenging the water quality of the drinking-water reservoirs. The identification and assessment of potential impacts is indispensable in water resource management and protection. This study investigates the drinking water reservoirs in Zhejiang Province to better understand the potential impact on water quality. Altogether seventy-three typical drinking reservoirs in Zhejiang Province encompassing various water storage levels were selected and evaluated. Using fifty-two reservoirs as training samples, the classification and regression tree (CART) method and sixteen comprehensive variables, including six sub-sets (land use, population, socio-economy, geographical features, inherent characteristics, and climate), were adopted to establish a decision-making model for identifying and assessing their potential impacts on drinking-water quality. The water quality class of the remaining twenty-one reservoirs was then predicted and tested based on the decision-making model, resulting in a water quality class attribution accuracy of 81.0%. Based on the decision rules and quantitative importance of the independent variables, industrial emissions was identified as the most important factor influencing the water quality of reservoirs; land use and human habitation also had a substantial impact on water quality. The results of this study provide insights into the factors impacting the water quality of reservoirs as well as basic information for protecting reservoir water resources. PMID:24919129
Perceived versus actual water quality: Community studies in rural Oaxaca, Mexico.
Rowles, Lewis Stetson; Alcalde, Reinaldo; Bogolasky, Francisca; Kum, Soyoon; Diaz-Arriaga, Farith A; Ayres, Craig; Mikelonis, Anne M; Toledo-Flores, Luis Javier; Alonso-Gutiérrez, Manuel Gerardo; Pérez-Flores, Maria Eufemia; Lawler, Desmond F; Ward, Peter M; Lopez-Cruz, Juana Yolanda; Saleh, Navid B
2018-05-01
Compromised water quality risks public health, which becomes particularly acute in economically marginalized communities. Although the majority of the clean-water-deprived population resides in Sub-Saharan Africa and Asia, a significant portion (32 million) lives in Meso- and Latin-America. Oaxaca is one of the marginalized southern states of Mexico, which has experienced high morbidity from infectious diseases and also has suffered from a high rate of infant mortality. However, there has been a paucity of reports on the status of water quality of culturally diverse rural Oaxaca. This study follows community-based participatory research methods to address the data gap by reporting on water quality (chemical and microbiological) and by exploring social realities and water use practices within and among communities. Surveys and water quality analyses were conducted on 73 households in three rural communities, which were selected based on the choice of water sources (i.e., river water, groundwater, and spring water). Statistically significant variations among communities were observed including the sanitation infrastructure (p-value 0.001), public perception on water quality (p-value 0.007), and actual microbiological quality of water (p-value 0.001). Results indicate a high prevalence of diarrheal diseases, a desire to improve water quality and reduce the cost of water, and a need for education on water quality and health in all the surveyed communities. The complexities among the three studied communities highlight the need for undertaking appropriate policies and water treatment solutions. Copyright © 2017 Elsevier B.V. All rights reserved.
Alameddine, Ibrahim; Jawhari, Gheeda; El-Fadel, Mutasem
2017-04-01
Perceptions developed by consumers regarding the quality of water reaching their household can affect the ultimate use of the water. This study identified key factors influencing consumers' perception of water quality in a highly urbanized coastal city, experiencing chronic water shortages, overexploitation of groundwater, and accelerated saltwater intrusion. Household surveys were administered to residents to capture views and perceptions of consumed water. Concomitantly, groundwater and tap water samples were collected and analyzed at each residence for comparison with perceptions. People's rating of groundwater quality was found to correlate to the measured water quality both in the dry and wet seasons. In contrast, perceptions regarding the water quality of the public water supply network did not show any correlation with the measured tap water quality indicators. Logistic regression models developed to predict perception based on salient variables indicated that age, apartment ownership, and levels of total dissolved solids play a significant role in shaping perceptions regarding groundwater quality. Perceptions concerning the water quality of the public water supply network appeared to be independent of the measured total dissolved solids levels at the tap but correlated to those measured in the wells. The study highlights misconceptions that can arise as a result of uncontrolled cross-connections of groundwater to the public supply network water and the development of misaligned perceptions based on prior consumption patterns, water shortages, and a rapidly salinizing groundwater aquifer.
Gu, Qing; Deng, Jinsong; Wang, Ke; Lin, Yi; Li, Jun; Gan, Muye; Ma, Ligang; Hong, Yang
2014-06-10
Various reservoirs have been serving as the most important drinking water sources in Zhejiang Province, China, due to the uneven distribution of precipitation and severe river pollution. Unfortunately, rapid urbanization and industrialization have been continuously challenging the water quality of the drinking-water reservoirs. The identification and assessment of potential impacts is indispensable in water resource management and protection. This study investigates the drinking water reservoirs in Zhejiang Province to better understand the potential impact on water quality. Altogether seventy-three typical drinking reservoirs in Zhejiang Province encompassing various water storage levels were selected and evaluated. Using fifty-two reservoirs as training samples, the classification and regression tree (CART) method and sixteen comprehensive variables, including six sub-sets (land use, population, socio-economy, geographical features, inherent characteristics, and climate), were adopted to establish a decision-making model for identifying and assessing their potential impacts on drinking-water quality. The water quality class of the remaining twenty-one reservoirs was then predicted and tested based on the decision-making model, resulting in a water quality class attribution accuracy of 81.0%. Based on the decision rules and quantitative importance of the independent variables, industrial emissions was identified as the most important factor influencing the water quality of reservoirs; land use and human habitation also had a substantial impact on water quality. The results of this study provide insights into the factors impacting the water quality of reservoirs as well as basic information for protecting reservoir water resources.
Atomically monodisperse nickel nanoclusters as highly active electrocatalysts for water oxidation
NASA Astrophysics Data System (ADS)
Joya, Khurram S.; Sinatra, Lutfan; Abdulhalim, Lina G.; Joshi, Chakra P.; Hedhili, M. N.; Bakr, Osman M.; Hussain, Irshad
2016-05-01
Achieving water splitting at low overpotential with high oxygen evolution efficiency and stability is important for realizing solar to chemical energy conversion devices. Herein we report the synthesis, characterization and electrochemical evaluation of highly active nickel nanoclusters (Ni NCs) for water oxidation at low overpotential. These atomically precise and monodisperse Ni NCs are characterized by using UV-visible absorption spectroscopy, single crystal X-ray diffraction and mass spectrometry. The molecular formulae of these Ni NCs are found to be Ni4(PET)8 and Ni6(PET)12 and are highly active electrocatalysts for oxygen evolution without any pre-conditioning. Ni4(PET)8 are slightly better catalysts than Ni6(PET)12 which initiate oxygen evolution at an amazingly low overpotential of ~1.51 V (vs. RHE; η ~ 280 mV). The peak oxygen evolution current density (J) of ~150 mA cm-2 at 2.0 V (vs. RHE) with a Tafel slope of 38 mV dec-1 is observed using Ni4(PET)8. These results are comparable to the state-of-the-art RuO2 electrocatalyst, which is highly expensive and rare compared to Ni-based materials. Sustained oxygen generation for several hours with an applied current density of 20 mA cm-2 demonstrates the long-term stability and activity of these Ni NCs towards electrocatalytic water oxidation. This unique approach provides a facile method to prepare cost-effective, nanoscale and highly efficient electrocatalysts for water oxidation.Achieving water splitting at low overpotential with high oxygen evolution efficiency and stability is important for realizing solar to chemical energy conversion devices. Herein we report the synthesis, characterization and electrochemical evaluation of highly active nickel nanoclusters (Ni NCs) for water oxidation at low overpotential. These atomically precise and monodisperse Ni NCs are characterized by using UV-visible absorption spectroscopy, single crystal X-ray diffraction and mass spectrometry. The molecular formulae of these Ni NCs are found to be Ni4(PET)8 and Ni6(PET)12 and are highly active electrocatalysts for oxygen evolution without any pre-conditioning. Ni4(PET)8 are slightly better catalysts than Ni6(PET)12 which initiate oxygen evolution at an amazingly low overpotential of ~1.51 V (vs. RHE; η ~ 280 mV). The peak oxygen evolution current density (J) of ~150 mA cm-2 at 2.0 V (vs. RHE) with a Tafel slope of 38 mV dec-1 is observed using Ni4(PET)8. These results are comparable to the state-of-the-art RuO2 electrocatalyst, which is highly expensive and rare compared to Ni-based materials. Sustained oxygen generation for several hours with an applied current density of 20 mA cm-2 demonstrates the long-term stability and activity of these Ni NCs towards electrocatalytic water oxidation. This unique approach provides a facile method to prepare cost-effective, nanoscale and highly efficient electrocatalysts for water oxidation. Electronic supplementary information (ESI) available: CCDC 1419754 and 1419731. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c6nr00709k
Lee, Casey J.; Murphy, Jennifer C.; Crawford, Charles G.; Deacon, Jeffrey R.
2017-10-24
The U.S. Geological Survey publishes information on concentrations and loads of water-quality constituents at 111 sites across the United States as part of the U.S. Geological Survey National Water Quality Network (NWQN). This report details historical and updated methods for computing water-quality loads at NWQN sites. The primary updates to historical load estimation methods include (1) an adaptation to methods for computing loads to the Gulf of Mexico; (2) the inclusion of loads computed using the Weighted Regressions on Time, Discharge, and Season (WRTDS) method; and (3) the inclusion of loads computed using continuous water-quality data. Loads computed using WRTDS and continuous water-quality data are provided along with those computed using historical methods. Various aspects of method updates are evaluated in this report to help users of water-quality loading data determine which estimation methods best suit their particular application.
7 CFR 634.23 - Water quality plan.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 6 2012-01-01 2012-01-01 false Water quality plan. 634.23 Section 634.23 Agriculture... AGRICULTURE LONG TERM CONTRACTING RURAL CLEAN WATER PROGRAM Participant RCWP Contracts § 634.23 Water quality plan. (a) The participant's water quality plan, developed with technical assistance by the NRCS or its...
Code of Federal Regulations, 2011 CFR
2011-10-01
... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Water quality. 414.5 Section 414.5 Public... OFFSTREAM STORAGE OF COLORADO RIVER WATER AND DEVELOPMENT AND RELEASE OF INTENTIONALLY CREATED UNUSED APPORTIONMENT IN THE LOWER DIVISION STATES Water Quality and Environmental Compliance § 414.5 Water quality. (a...
Code of Federal Regulations, 2010 CFR
2010-10-01
... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Water quality. 414.5 Section 414.5 Public... OFFSTREAM STORAGE OF COLORADO RIVER WATER AND DEVELOPMENT AND RELEASE OF INTENTIONALLY CREATED UNUSED APPORTIONMENT IN THE LOWER DIVISION STATES Water Quality and Environmental Compliance § 414.5 Water quality. (a...
Water quality of four major lakes in Mississippi, USA: Impacts on human and aquatic ecosystem health
USDA-ARS?s Scientific Manuscript database
Harmful algal blooms (HABs), harmful microorganisms (pathogens) and toxic metals represent three major agents of water quality deterioration. Better water quality is of utmost importance to water bodies that provide recreational opportunities, even better quality is expected in the water bodies that...
Code of Federal Regulations, 2012 CFR
2012-10-01
... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Water quality. 414.5 Section 414.5 Public... OFFSTREAM STORAGE OF COLORADO RIVER WATER AND DEVELOPMENT AND RELEASE OF INTENTIONALLY CREATED UNUSED APPORTIONMENT IN THE LOWER DIVISION STATES Water Quality and Environmental Compliance § 414.5 Water quality. (a...
Code of Federal Regulations, 2013 CFR
2013-10-01
... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Water quality. 414.5 Section 414.5 Public... OFFSTREAM STORAGE OF COLORADO RIVER WATER AND DEVELOPMENT AND RELEASE OF INTENTIONALLY CREATED UNUSED APPORTIONMENT IN THE LOWER DIVISION STATES Water Quality and Environmental Compliance § 414.5 Water quality. (a...
7 CFR 634.23 - Water quality plan.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 6 2013-01-01 2013-01-01 false Water quality plan. 634.23 Section 634.23 Agriculture... AGRICULTURE LONG TERM CONTRACTING RURAL CLEAN WATER PROGRAM Participant RCWP Contracts § 634.23 Water quality plan. (a) The participant's water quality plan, developed with technical assistance by the NRCS or its...
40 CFR 130.8 - Water quality report.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 22 2014-07-01 2013-07-01 true Water quality report. 130.8 Section 130.8 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY PLANNING AND MANAGEMENT § 130.8 Water quality report. (a) Each State shall prepare and submit biennially to...
Code of Federal Regulations, 2014 CFR
2014-10-01
... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Water quality. 414.5 Section 414.5 Public... OFFSTREAM STORAGE OF COLORADO RIVER WATER AND DEVELOPMENT AND RELEASE OF INTENTIONALLY CREATED UNUSED APPORTIONMENT IN THE LOWER DIVISION STATES Water Quality and Environmental Compliance § 414.5 Water quality. (a...
7 CFR 634.23 - Water quality plan.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 6 2014-01-01 2014-01-01 false Water quality plan. 634.23 Section 634.23 Agriculture... AGRICULTURE LONG TERM CONTRACTING RURAL CLEAN WATER PROGRAM Participant RCWP Contracts § 634.23 Water quality plan. (a) The participant's water quality plan, developed with technical assistance by the NRCS or its...
Physical properties of cryovolcanic brines: Applications to the evolution of Ganymede
NASA Technical Reports Server (NTRS)
Kargel, Jeffrey S.
1991-01-01
Carbonaceous chondrites contain abundant veins of water soluble salts, including carbonates and hydrated sulfates of Mg, Ca, Na, Ni, and Fe. These constitute over 1/4 of the mass of the meteorite Orgueil. Magnesium sulfate is the most abundant salt, constituting nearly half the mass of all salt components combined (anhydrous), and 73 pct. of the highly water soluble salts. The assumption that icy satellites and asteroids contain rock compositionally similar to carbonaceous chondrites suggests that salts may be important in the cryoigneous evolution of icy satellites and asteroids. Ordinary chondrites, an alternative rock component of icy satellites, lack abundant salts, although their anhydrous silicate assemblages are unstable with respect to water and would react to produce salts upon initial melting of ice. Some basic physiochemical properties are reviewed of likely cryovolcanic brines and how the existence of soluble salts in Ganymede might affect its structure and evolution is considered. Observations indicate late stage (post heavy bombardment and post tectonic) volcanism on Ganymede. The highly fluid character of Ganymedian volcanism is consistent with extrusions of either water or salt water brines.
Brown, Juliane B.
2008-01-01
Historical water-quality data in the National Park Service Southern Colorado Plateau Network have been collected irregularly and with little followup interpretation, restricting the value of the data. To help address these issues, to inform future water-quality monitoring planning efforts, and to address relevant National Park Service Inventory and Monitoring Program objectives, the U.S. Geological Survey, in cooperation with the National Park Service, compiled, reviewed, and summarized available historical water-quality data for 19 park units in the Southern Colorado Plateau Network. The data are described in terms of availability by major water-quality classes, park unit, site type, and selected identified water sources. The report also describes the geology, water resources, water-quality issues, data gaps, and water-quality standard exceedances identified in five of the park units determined to be of high priority. The five park units are Bandelier National Monument in New Mexico, Canyon de Chelly National Monument in Arizona, Chaco Culture National Historical Park in New Mexico, Glen Canyon National Recreation Area in Arizona and Utah, and Mesa Verde National Park in Colorado. Statistical summaries of water-quality characteristics are presented and considerations for future water-quality monitoring are provided for these five park units.
General introduction for the “National Field Manual for the Collection of Water-Quality Data”
,
2018-02-28
BackgroundAs part of its mission, the U.S. Geological Survey (USGS) collects data to assess the quality of our Nation’s water resources. A high degree of reliability and standardization of these data are paramount to fulfilling this mission. Documentation of nationally accepted methods used by USGS personnel serves to maintain consistency and technical quality in data-collection activities. “The National Field Manual for the Collection of Water-Quality Data” (NFM) provides documented guidelines and protocols for USGS field personnel who collect water-quality data. The NFM provides detailed, comprehensive, and citable procedures for monitoring the quality of surface water and groundwater. Topics in the NFM include (1) methods and protocols for sampling water resources, (2) methods for processing samples for analysis of water quality, (3) methods for measuring field parameters, and (4) specialized procedures, such as sampling water for low levels of mercury and organic wastewater chemicals, measuring biological indicators, and sampling bottom sediment for chemistry. Personnel who collect water-quality data for national USGS programs and projects, including projects supported by USGS cooperative programs, are mandated to use protocols provided in the NFM per USGS Office of Water Quality Technical Memorandum 2002.13. Formal training, for example, as provided in the USGS class, “Field Water-Quality Methods for Groundwater and Surface Water,” and field apprenticeships supplement the guidance provided in the NFM and ensure that the data collected are high quality, accurate, and scientifically defensible.
NASA Astrophysics Data System (ADS)
Chen, Y.; Han, D.
2017-12-01
Water system is an essential component in a smart city for its sustainability and resilience. The freshness and beauty of the water body would please people as well as benefit the local aquatic ecosystems. Water quality monitoring approach has evolved from the manual lab-based monitoring approach to the manual in-situ monitoring approach, and finally to the latest wireless-sensor-network (WSN) based solutions in recent decades. The development of the in-situ water quality sensors enable humans to collect high-frequency and real-time water quality data. This poster aims to explore the advantages of the high-frequency water quality data over the low-frequency data collected manually. The data is collected by a remote real-time high-frequency water quality monitor system based on the cutting edge smart city infrastructure in Bristol - `Bristol Is Open'. The water quality of Bristol Floating Harbour is monitored which is the focal area of Bristol with new buildings and features redeveloped in the past decades. This poster will first briefly introduce the water quality monitoring system, followed by the analysis of the advantages of the sub-hourly water quality data. Thus, the suggestion on the monitoring frequency will be given.
R2 Water Quality Portal Monitoring Stations
The Water Quality Data Portal (WQP) provides an easy way to access data stored in various large water quality databases. The WQP provides various input parameters on the form including location, site, sampling, and date parameters to filter and customize the returned results. The The Water Quality Portal (WQP) is a cooperative service sponsored by the United States Geological Survey (USGS), the Environmental Protection Agency (EPA) and the National Water Quality Monitoring Council (NWQMC) that integrates publicly available water quality data from the USGS National Water Information System (NWIS) the EPA STOrage and RETrieval (STORET) Data Warehouse, and the USDA ARS Sustaining The Earth??s Watersheds - Agricultural Research Database System (STEWARDS).
A comparison of water vapor quantities from model short-range forecasts and ARM observations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hnilo, J J
2006-03-17
Model evolution and improvement is complicated by the lack of high quality observational data. To address a major limitation of these measurements the Atmospheric Radiation Measurement (ARM) program was formed. For the second quarter ARM metric we will make use of new water vapor data that has become available, and called the 'Merged-sounding' value added product (referred to as OBS, within the text) at three sites: the North Slope of Alaska (NSA), Darwin Australia (DAR) and the Southern Great Plains (SGP) and compare these observations to model forecast data. Two time periods will be analyzed March 2000 for the SGPmore » and October 2004 for both DAR and NSA. The merged-sounding data have been interpolated to 37 pressure levels (e.g., from 1000hPa to 100hPa at 25hPa increments) and time averaged to 3 hourly data for direct comparison to our model output.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hnilo, J.
2006-03-17
Model evolution and improvement is complicated by the lack of high quality observational data. To address a major limitation of these measurements the Atmospheric Radiation Measurement (ARM) program was formed. For the second quarter ARM metric we will make use of new water vapor data that has become available, and called the “Mergedsounding” value added product (referred to as OBS, within the text) at three sites: the North Slope of Alaska (NSA), Darwin Australia (DAR) and the Southern Great Plains (SGP) and compare these observations to model forecast data. Two time periods will be analyzed March 2000 for the SGPmore » and October 2004 for both DAR and NSA. The merged-sounding data have been interpolated to 37 pressure levels (e.g., from 1000hPa to 100hPa at 25hPa increments) and time averaged to 3 hourly data for direct comparison to our model output.« less
Kroening, Sharon E.
2008-01-01
Surface- and ground-water quality data from the Mosquito Lagoon Basin were compiled and analyzed to: (1) describe historical and current monitoring in the basin, (2) summarize surface- and ground-water quality conditions with an emphasis on identifying areas that require additional monitoring, and (3) develop a water-quality monitoring network to meet the goals of Canaveral National Seashore (a National Park) and to fill gaps in current monitoring. Water-quality data were compiled from the U.S. Environmental Protection Agency's STORET system, the U.S. Geological Survey's National Water Information System, or from the agency which collected the data. Most water-quality monitoring focused on assessing conditions in Mosquito Lagoon. Significant spatial and/or seasonal variations in water-quality constituents in the lagoon were quantified for pH values, fecal coliform bacteria counts, and concentrations of dissolved oxygen, total nitrogen, total phosphorus, chlorophyll-a, and total suspended solids. Trace element, pesticide, and ground-water-quality data were more limited. Organochlorine insecticides were the major class of pesticides analyzed. A surface- and ground-water-quality monitoring network was designed for the Mosquito Lagoon Basin which emphasizes: (1) analysis of compounds indicative of human activities, including pesticides and other trace organic compounds present in domestic and industrial waste; (2) greater data collection in the southern part of Mosquito Lagoon where spatial variations in water-quality constituents were quantified; and (3) additional ground-water-quality data collection in the surficial aquifer system and Upper Floridan aquifer. Surface-water-quality data collected as part of this network would include a fixed-station monitoring network of eight sites in the southern part of the basin, including a canal draining Oak Hill. Ground-water quality monitoring should be done routinely at about 20 wells in the surficial aquifer system and Upper Floridan aquifer, distributed between developed and undeveloped parts of the basin. Water samples collected should be analyzed for a wide range of constituents, including physical properties, nutrients, suspended sediment, and constituents associated with increased urban development such as pesticides, other trace organic compounds associated with domestic and industrial waste, and trace elements.
Water Quality Assessment of Ayeyarwady River in Myanmar
NASA Astrophysics Data System (ADS)
Thatoe Nwe Win, Thanda; Bogaard, Thom; van de Giesen, Nick
2015-04-01
Myanmar's socio-economic activities, urbanisation, industrial operations and agricultural production have increased rapidly in recent years. With the increase of socio-economic development and climate change impacts, there is an increasing threat on quantity and quality of water resources. In Myanmar, some of the drinking water coverage still comes from unimproved sources including rivers. The Ayeyarwady River is the main river in Myanmar draining most of the country's area. The use of chemical fertilizer in the agriculture, the mining activities in the catchment area, wastewater effluents from the industries and communities and other development activities generate pollutants of different nature. Therefore water quality monitoring is of utmost importance. In Myanmar, there are many government organizations linked to water quality management. Each water organization monitors water quality for their own purposes. The monitoring is haphazard, short term and based on individual interest and the available equipment. The monitoring is not properly coordinated and a quality assurance programme is not incorporated in most of the work. As a result, comprehensive data on the water quality of rivers in Myanmar is not available. To provide basic information, action is needed at all management levels. The need for comprehensive and accurate assessments of trends in water quality has been recognized. For such an assessment, reliable monitoring data are essential. The objective of our work is to set-up a multi-objective surface water quality monitoring programme. The need for a scientifically designed network to monitor the Ayeyarwady river water quality is obvious as only limited and scattered data on water quality is available. However, the set-up should also take into account the current socio-economic situation and should be flexible to adjust after first years of monitoring. Additionally, a state-of-the-art baseline river water quality sampling program is required which will take place during the low water season of March, 2015. The water quality information available for the Ayeyarwady as well as the baseline sampling of March 2015 will be presented. Furthermore, the specific scientific ideas but also organisational challenges for the future surface water quality monitoring network of the Ayeyarwady will be discussed.
Khan, Stuart J; Deere, Daniel; Leusch, Frederic D L; Humpage, Andrew; Jenkins, Madeleine; Cunliffe, David
2015-11-15
Among the most widely predicted and accepted consequences of global climate change are increases in both the frequency and severity of a variety of extreme weather events. Such weather events include heavy rainfall and floods, cyclones, droughts, heatwaves, extreme cold, and wildfires, each of which can potentially impact drinking water quality by affecting water catchments, storage reservoirs, the performance of water treatment processes or the integrity of distribution systems. Drinking water guidelines, such as the Australian Drinking Water Guidelines and the World Health Organization Guidelines for Drinking-water Quality, provide guidance for the safe management of drinking water. These documents present principles and strategies for managing risks that may be posed to drinking water quality. While these principles and strategies are applicable to all types of water quality risks, very little specific attention has been paid to the management of extreme weather events. We present a review of recent literature on water quality impacts of extreme weather events and consider practical opportunities for improved guidance for water managers. We conclude that there is a case for an enhanced focus on the management of water quality impacts from extreme weather events in future revisions of water quality guidance documents. Copyright © 2015 Elsevier Ltd. All rights reserved.
High Plains regional ground-water study
Dennehy, Kevin F.
2000-01-01
Over the last 25 years, industry and government have made large financial investments aimed at improving water quality across the Nation. Significant progress has been made; however, many water-quality concerns remain. In 1991, the U.S. Geological Survey (USGS) began implementing a full-scale National Water-Quality Assessment Program to provide consistent and scientifically sound information for managing the Nation's water resources. The goals of the NAWQA Program are to (1) describe current water-quality conditions for a large part of the Nation's freshwater streams and aquifers, (2) describe how water quality is changing over time, and (3) improve our understanding of the primary natural and human factors affecting water quality. Assessing the quality of water in every location in the Nation would not be practical; therefore, NAWQA Program studies are conducted within a set of areas called study units (fig. 1). These study units are composed of more than 50 important river and aquifer systems that represent the diverse geography, water resources, and land and water uses of the Nation. The High Plains Regional Ground-Water Study is one such study area, designed to address issues relevant to the High Plains Aquifer system while supplementing water-quality information collected in other study units across the Nation. Implementation of the NAWQA Program for the High Plains Regional Ground-Water Study area began in 1998.
Sadiq, Rehan; Rodriguez, Manuel J
2005-04-01
Interpreting water quality data routinely generated for control and monitoring purposes in water distribution systems is a complicated task for utility managers. In fact, data for diverse water quality indicators (physico-chemical and microbiological) are generated at different times and at different locations in the distribution system. To simplify and improve the understanding and the interpretation of water quality, methodologies for aggregation and fusion of data must be developed. In this paper, the Dempster-Shafer theory also called theory of evidence is introduced as a potential methodology for interpreting water quality data. The conceptual basis of this methodology and the process for its implementation are presented by two applications. The first application deals with the interpretation of spatial water quality data fusion, while the second application deals with the development of water quality index based on key monitored indicators. Based on the obtained results, the authors discuss the potential contribution of theory of evidence as a decision-making tool for water quality management.
The Maladies of Water and War: Addressing Poor Water Quality in Iraq
2013-01-01
Water is essential in providing nutrients, but contaminated water contributes to poor population health. Water quality and availability can change in unstructured situations, such as war. To develop a practical strategy to address poor water quality resulting from intermittent wars in Iraq, I reviewed information from academic sources regarding waterborne diseases, conflict and war, water quality treatment, and malnutrition. The prevalence of disease was high in impoverished, malnourished populations exposed to contaminated water sources. The data aided in developing a strategy to improve water quality in Iraq, which encompasses remineralized water from desalination plants, health care reform, monitoring and evaluation systems, and educational public health interventions. PMID:23597360
NASA Astrophysics Data System (ADS)
Hurdebise, Quentin; Rixen, Toma; De Ligne, Anne; Vincke, Caroline; Heinesch, Bernard; Aubinet, Marc
2016-04-01
With the development of eddy covariance networks like Fluxnet, ICOS or NEON, long-term data series of carbon dioxide, water vapor and other gas exchanges between terrestrial ecosystems and atmosphere will become more and more numerous. However, long-term analyses of such exchanges require a good understanding of measurement conditions during the investigated period. Independently of climate drivers, measurements may indeed be influenced by measurement conditions themselves subjected to long-term variability due to vegetation growth or set-up changes. The present research refers to the Vielsalm Terrestrial Observatory (VTO) where fluxes of momentum, carbon dioxide, latent and sensible heat have been continuously measured by eddy covariance during twenty years. VTO is an ICOS site installed in a mixed forest (beech, silver fir, Douglas fir, Norway spruce) in the Belgian Ardennes. A multidisciplinary approach was developed in order to investigate the spatial and temporal evolution of several site characteristics: -displacement height (d) and relative measurement height (z-d) were determined using a spectral approach that compared observed and theoretical cospectra; -turbulence statistics were analyzed in the context of Monin-Obukhov similarity theory; -tree height during the measurement period was obtained by combining tree height inventories, a LIDAR survey and tree growth models; -measurement footprint was determined by using a footprint model. A good agreement was found between the three first approaches. Results show notably that z-d was subjected to both temporal and spatial evolution. Temporal evolution resulted from continuous tree growth as well as from a tower raise, achieved in 2009. Spatial evolution, due to canopy heterogeneity, was also observed. The impacts of these changes on measurements are investigated. In particular, it was shown that they affect measurement footprint, flux spectral corrections and flux quality. All these effects must be taken into consideration in order to disentangle long-term flux evolutions due to climate or phenology from changes resulting from measurement set-up changes.
Water Quality Evaluation of the Yellow River Basin Based on Gray Clustering Method
NASA Astrophysics Data System (ADS)
Fu, X. Q.; Zou, Z. H.
2018-03-01
Evaluating the water quality of 12 monitoring sections in the Yellow River Basin comprehensively by grey clustering method based on the water quality monitoring data from the Ministry of environmental protection of China in May 2016 and the environmental quality standard of surface water. The results can reflect the water quality of the Yellow River Basin objectively. Furthermore, the evaluation results are basically the same when compared with the fuzzy comprehensive evaluation method. The results also show that the overall water quality of the Yellow River Basin is good and coincident with the actual situation of the Yellow River basin. Overall, gray clustering method for water quality evaluation is reasonable and feasible and it is also convenient to calculate.
NASA Astrophysics Data System (ADS)
Liu, W.; Kuo, Y. M.
2016-12-01
The Middle Route of China's South-to-North Water Transfer (MSNW) and Yangtze-Han River Water Diversion (YHWD) Projects have been operated since 2014, which may deteriorate water quality in Han River. The 11 water sampling sites distributed from the middle and down streams of Han River watershed were monitored monthly between July 2014 and December 2015. Factor analysis and cluster analysis were applied to investigate the major pollution types and main variables influencing water quality in Han River. The factor analysis distinguishes three main pollution types (agricultural nonpoint source, organic, and phosphorus point source pollution) affecting water quality of Han River. Cluster analysis classified all sampling sites into four groups and determined their pollution source for both Dry and Wet seasons. The sites located at central city receive point source pollution in both seasons. The water quality in downstream Han River (excluding central city sites) was influenced by nonpoint source pollution from Jianghan Plain. Variations of water qualities are associated with hydrological conditions varied from operations of engineering projects and seasonal variability especially in Dry season. Good water quality as Class III mainly occurred when flow rate is greater than 800 cms in Dry season. The low average flow rate below 583 cms will degrade water quality as Class V at almost all sites. Elevating the flow rate discharged from MSNW and YHWD Projects to Han River can avoid degrading water quality especially in low flow conditions and may decrease the probability of algal bloom occurrence in Han River. Increasing the flow rate from 400 cms to 700 cms in main Han River can obviously improve the water quality of Han River. The investigation of relationships between water quality and flow rate in both projects can provide management strategies of water quality for various flow conditions.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-07
... Effective Date for the Water Quality Standards for the State of Florida's Lakes and Flowing Waters AGENCY... Protection Agency (EPA) is finalizing an extension of the March 6, 2012 effective date of the ``Water Quality... INFORMATION: I. General Information Does this action apply to me? Citizens concerned with water quality in...
Water resources data, North Carolina, water year 2004. Volume 2: Ground-water records
Howe, S.S.; Breton, P.L.; Chapman, M.J.
2005-01-01
Water-resources data for the 2004 water year for North Carolina consist of records of stage, discharge, water quality for streams; stage and contents for lakes and reservoirs; precipitation; and ground-water levels and water quality of ground water. Volume 1 contains discharge records for 217 gaging stations; stage and contents for 58 lakes and reservoirs; stage only records for 22 gaging stations; elevations for 9 stations; water quality for 39 gaging stations and 5 miscellaneous sites, and continuous water quality for 35 sites; and continuous precipitation at 127 sites. Volume 2 contains ground-water-level data from 161 observation wells, ground-water-quality data from 38 wells, continuous water quality for 7 sites and continuous precipitation at 7 sites. Additional water data were collected at 51 sites not involved in the systematic data-collection program, and are published as miscellaneous measurements in Volume 1. The collection of water-resources data in North Carolina is a part of the National Water-Data System operated by the U.S. Geological Survey in cooperation with State, municipal, and Federal agencies.
USDA-ARS?s Scientific Manuscript database
Aquatic animals are healthiest and grow best when environmental conditions are within certain ranges that define, for a particular species, “good” water quality. From the outset, successful aquaculture requires a high-quality water supply. Water quality in aquaculture systems also deteriorates as an...
Water Resources Data - New Jersey, Water Year 1999, Volume 3, Water-Quality Data
DeLuca, M.J.; Romanok, K.M.; Riskin, M.L.; Mattes, G.L.; Thomas, A.M.; Gray, B.J.
2000-01-01
Water-resources data for the 1999 water year for New Jersey are presented in three volumes, and consists of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels and water quality of ground water. Volume 3 contains a summary of surface and ground water hydrologic conditions for the 1999 water year, a listing of current water-resource projects in New Jersey, a bibliography of water-related reports, articles, and fact sheets for New Jersey completed by the Geological Survey in recent years, water-quality records of chemical analyses from 133 surface-water stations, 46 miscellaneous surface-water sites, 30 ground-water stations, 41 miscellaneous ground-water sites, and records of daily statistics of temperature and other physical measurements from 17 continuous-monitoring stations. Locations of water-quality stations are shown in figures 11 and 17-20. Locations of miscellaneous water-quality sites are shown in figures 29-32 and 34. These data represent the part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in New Jersey.
Guzmán, Blanca Lisseth; Nava, Gerardo; Díaz, Paula
2015-08-01
The quality of water for human consumption has been correlated with the occurrence of different diseases. Studying the relationship between these parameters would allow determining the impact of water quality on human health, and to direct preventative measures and promote environmental health. To analyze the quality of water intended for human consumption and its association with morbimortality in Colombia, 2008-2012. The database for surveillance of water quality was analyzed by means of descriptive statistics of the principal indicators (total coliforms, Escherichia coli , turbidity, color, pH, free residual chlorine and water quality risk index). The results were correlated with infant mortality and morbidity due to acute diarrheal diseases, foodborne diseases and hepatitis A. A risk map was prepared to identify those municipalities with the highest risk of water contamination and infant mortality. A high percentage of municipalities did not conform to existing standards for water potability values. Problems were identified that were related to presence of E. coli and total coliforms, as well as absence of free residual chlorine, a situation that was exacerbated in rural areas. Water quality showed a high correlation with infant mortality, highlighting its importance for children's health. Water quality was found to have an important impact on infant mortality. Improving water quality in Colombia will require policies that strengthen water supply systems in this country. Strengthening of environmental health surveillance programs is essential to guide actions aimed at improving water quality and exert a positive impact on health.
Hashimoto, Tadafumi; Osawa, Yusuke; Itoh, Shinsuke; Mochizuki, Masahito; Nishimoto, Kazutoshi
2013-06-01
To prevent primary water stress corrosion cracking (PWSCC), water jet peening (WJP) has been used on the welds of Ni-based alloys in pressurized water reactors (PWRs). Before WJP, the welds are machined and buffed in order to conduct a penetrant test (PT) to verify the weld qualities to access, and microstructure evolution takes place in the target area due to the severe plastic deformation. The compressive residual stresses induced by WJP might be unstable under elevated temperatures because of the high dislocation density in the compressive stress layer. Therefore, the stability of the compressive residual stresses caused by WJP was investigated during long-term operation by considering the microstructure evolution due to the working processes. The following conclusions were made: The compressive residual stresses were slightly relaxed in the surface layers of the thermally aged specimens. There were no differences in the magnitude of the relaxation based on temperature or time. The compressive residual stresses induced by WJP were confirmed to remain stable under elevated temperatures. The stress relaxation at the surface followed the Johnson-Mehl equation, which states that stress relaxation can occur due to the recovery of severe plastic strain, since the estimated activation energy agrees very well with the self-diffusion energy for Ni. By utilizing the additivity rule, it was indicated that stress relaxation due to recovery is completed during the startup process. It was proposed that the long-term stability of WJP under elevated temperatures must be assessed based on compressive stresses with respect to the yield stress. Thermal elastic-plastic creep analysis was performed to predict the effect of creep strain. After 100 yr of simulated continuous operation at 80% capacity, there was little change in the WJP compressive stresses under an actual operating temperature of 623 K. Therefore, the long-term stability of WJP during actual operation was analytically predicted.
NASA Astrophysics Data System (ADS)
Lin, Botao; Jin, Yan; Pang, Huiwen; Cerato, Amy B.
2016-04-01
The success of steam-assisted gravity drainage (SAGD) is strongly dependent on the formation of a homogeneous and highly permeable zone in the land-facies Karamay oil sand reservoirs. To accomplish this, hydraulic fracturing is applied through controlled water injection to a pair of horizontal wells to create a dilation zone between the dual wells. The mechanical response of the reservoirs during this injection process, however, has remained unclear for the land-facies oil sand that has a loosely packed structure. This research conducted triaxial, permeability and scanning electron microscopy (SEM) tests on the field-collected oil sand samples. The tests evaluated the influences of the field temperature, confining stress and injection pressure on the dilation mechanisms as shear dilation and tensile parting during injection. To account for petrophysical heterogeneity, five reservoir rocks including regular oil sand, mud-rich oil sand, bitumen-rich oil sand, mudstone and sandstone were investigated. It was found that the permeability evolution in the oil sand samples subjected to shear dilation closely followed the porosity and microcrack evolutions in the shear bands. In contrast, the mudstone and sandstone samples developed distinct shear planes, which formed preferred permeation paths. Tensile parting expanded the pore space and increased the permeability of all the samples in various degrees. Based on this analysis, it is concluded that the range of injection propagation in the pay zone determines the overall quality of hydraulic fracturing, while the injection pressure must be carefully controlled. A region in a reservoir has little dilation upon injection if it remains unsaturated. Moreover, a cooling of the injected water can strengthen the dilation potential of a reservoir. Finally, it is suggested that the numerical modeling of water injection in the Karamay oil sand reservoirs must take into account the volumetric plastic strain in hydrostatic loading.
NASA Astrophysics Data System (ADS)
Taylor, C. B.
1994-06-01
With the exception of water-bearing remnants of earlier fluvial gravels overlying basement, the sediments of the Poverty Bay flats have accumulated during the postglacial period of the past 14 000 years, and have been tilted and deformed by recent tectonism. A sequence of gravel aquifers, separated by poorly permeable silt layers, lies between surface and basement, which is at depths varying between 50 and 200 m. A shallow sand/silt aquifer is situated near the coast. This study applies evidence of chemical and isotopic properties of river and ground water to clarify the recharge mechanisms, chemical evolution and age of the ground water in the aquifers. Particular attention is paid to the evolution of dissolved inorganic carbon content, applying carbon-14 data measured by accelerator mass spectrometry. Most of the ground water is recharged from the Waipaoa River, which flows across the flats and discharges into Poverty Bay. The two deepest aquifers (Matokitoki and Makauri) are both tritium-free; the deeper Matokitoki Gravels yield water of age about 4300 years since recharge (possibly up to 1300 years greater), but the Makauri water is no older than 100-200 years, discharging slowly through overlying aquitards near the limit of closest approach to the present coast.
Water Quality Assessment and Management
Overview of Clean Water Act (CWA) restoration framework including; water quality standards, monitoring/assessment, reporting water quality status, TMDL development, TMDL implementation (point & nonpoint source control)
The derivation of water quality criteria of copper in Biliu River
NASA Astrophysics Data System (ADS)
Zheng, Hongbo; Jia, Xinru
2018-03-01
Excessive copper in water can be detrimental to the health of human and aquatic life. China has promulgated Environmental Quality Standards for Surface Water to control water pollution, but uniform standard values may cause under-protection or over-protection. Therefore, the basic research work on water quality criteria of water source or reservoir is urgently needed. This study deduces the acute and chronic Water Quality Criteria (WQC) of copper in Biliu River by Species Sensitivity Distribution method (SSD). The result shows that BiDoseResp is the most suitable model and the acute and chronic water quality benchmark of copper are 10.72 µg•L-1 and 5.86 µg•L-1. This study provides basis for the construction of water quality standard of Liaoning and the environmental management of Biliu River.
Chapter 5: Surface water quality sampling in streams and canals
USDA-ARS?s Scientific Manuscript database
Surface water sampling and water quality assessments have greatly evolved in the United States since the 1970s establishment of the Clean Water Act. Traditionally, water quality referred to only the chemical characteristics of the water and its toxicological properties related to drinking water or ...
Berndt, Marian P.; Katz, Brian G.
2000-01-01
In accordance with guidelines set forth by the Office of Water Quality in the Water Resources Division of the U.S. Geological Survey, a quality-assurance plan was created for use by the Florida District's North Florida Program Office in conducting water-quality activities. This plan documents the standards, policies, and procedures used by the North Florida Program Office for activities related to the collection, processing, storage, analysis, and publication of water-quality data.
Data from selected U.S. Geological Survey National Stream Water-Quality Networks (WQN)
Alexander, Richard B.; Slack, J.R.; Ludtke, A.S.; Fitzgerald, K.K.; Schertz, T.L.; Briel, L.I.; Buttleman, K.P.
1996-01-01
This CD-ROM set contains data from two USGS national stream water-quality networks, the Hydrologic Benchmark Network (HBN) and the National Stream Quality Accounting Network (NASQAN), operated during the past 30 years. These networks were established to provide national and regional descriptions of stream water-quality conditions and trends, based on uniform monitoring of selected watersheds throughout the United States, and to improve our understanding of the effects of the natural environment and human activities on water quality. The HBN, consisting of 63 relatively small, minimally disturbed watersheds, provides data for investigating naturally induced changes in streamflow and water quality and the effects of airborne substances on water quality. NASQAN, consisting of 618 larger, more culturally influenced watersheds, provides information for tracking water-quality conditions in major U.S. rivers and streams.
2012-01-09
utilize LID techniques to enable greater on-site infiltration of storm water to improve storm water quality and restore natural water quality conditions...systems and conveyed through above- and below-ground piping to concrete roadside ditches. Stonn Water Quality Storm water quality monitoring has been...process of being awarded and implemented. The results of all referenced storm water quality and septic inspection reports is available upon request to
Water quality of Cisadane River based on watershed segmentation
NASA Astrophysics Data System (ADS)
Effendi, Hefni; Ayu Permatasari, Prita; Muslimah, Sri; Mursalin
2018-05-01
The growth of population and industrialization combined with land development along river cause water pollution and environmental deterioration. Cisadane River is one of the river in Indonesia where urbanization, industrialization, and agricultural are extremely main sources of pollution. Cisadane River is an interesting case for investigating the effect of land use to water quality and comparing water quality in every river segment. The main objectives with this study were to examine if there is a correlation between land use and water quality in Cisadane River and there is a difference in water quality between the upstream section of Cisadane River compared with its downstream section. This study compared water quality with land use condition in each segment of river. Land use classification showed that river segment that has more undeveloped area has better water quality compared to river segment with developed area. in general, BOD and COD values have increased from upstream to downstream. However, BOD and COD values do not show a steady increase in each segment Water quality is closely related to the surrounding land use.Therefore, it can not be concluded that the water quality downstream is worse than in the upstream area.
Littin, Gregory R.; Schnoebelen, Douglas J.
2010-01-01
The Cedar River alluvial aquifer is the primary source of municipal water in the Cedar Rapids, Iowa area. Municipal wells are completed in the alluvial aquifer at approximately 40 to 80 feet deep. The City of Cedar Rapids and the U.S. Geological Survey have been conducting a cooperative study of the groundwater-flow system and water quality near the well fields since 1992. Previous cooperative studies between the City of Cedar Rapids and the U.S. Geological Survey have documented hydrologic and water-quality data, geochemistry, and groundwater models. Water-quality samples were collected for studies involving well field monitoring, trends, source-water protection, groundwater geochemistry, evaluation of surface and ground-water interaction, assessment of pesticides in groundwater and surface water, and to evaluate water quality near a wetland area in the Seminole well field. Typical water-quality analyses included major ions (boron, bromide, calcium, chloride, fluoride, iron, magnesium, manganese, potassium, silica, sodium, and sulfate), nutrients (ammonia as nitrogen, nitrite as nitrogen, nitrite plus nitrate as nitrogen, and orthophosphate as phosphorus), dissolved organic carbon, and selected pesticides including two degradates of the herbicide atrazine. In addition, two synoptic samplings included analyses of additional pesticide degradates in water samples. Physical field parameters (alkalinity, dissolved oxygen, pH, specific conductance and water temperature) were recorded with each water sample collected. This report presents the results of water quality data-collection activities from January 1999 through December 2005. Methods of data collection, quality-assurance samples, water-quality analyses, and statistical summaries are presented. Data include the results of water-quality analyses from quarterly and synoptic sampling from monitoring wells, municipal wells, and the Cedar River.
40 CFR 35.925-2 - Water quality management plans and agencies.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Water quality management plans and... Water Act § 35.925-2 Water quality management plans and agencies. That the project is consistent with any applicable water quality management (WQM) plan approved under section 208 or section 303(e) of the...
Annotated bibliography on forest practices legislation related to water quality
Neil K. Huyler; David McMath; Daphne Hewitt
1999-01-01
Includes annotated citations of literature on forest practices regulations related to all aspects of water quality protection. The bibliography is divided into three sections: 1) Water quality protection during timber harvesting; 2) Methods for assessing the costs and benefits of water quality protection; and 3) Effectiveness of regulatory programs in protecting water...
40 CFR 131.6 - Minimum requirements for water quality standards submission.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Minimum requirements for water quality standards submission. 131.6 Section 131.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS General Provisions § 131.6 Minimum requirements for water quality standards submission. The...
40 CFR 131.6 - Minimum requirements for water quality standards submission.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 22 2011-07-01 2011-07-01 false Minimum requirements for water quality standards submission. 131.6 Section 131.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS General Provisions § 131.6 Minimum requirements for water quality standards submission. The...
USDA-ARS?s Scientific Manuscript database
Water quality trading (WQT) is a market-based approach that allows point sources of water pollution to meet their water quality obligations by purchasing credits from the reduced discharges from other point or nonpoint sources. Non-permitted animal operations and fields of permitted animal operatio...
Water resources data, Idaho, 2003; Volume 3. Ground water records
Campbell, A.M.; Conti, S.N.; O'Dell, I.
2003-01-01
Water resources data for the 2003 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 208 stream-gaging stations and 14 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 50 stream-gaging stations and partial record sites, 3 lakes sites, and 398 groundwater wells; and water levels for 427 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.
Water resources data, Idaho, 2004; Volume 3. Ground water records
Campbell, A.M.; Conti, S.N.; O'Dell, I.
2005-01-01
Water resources data for the 2004 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 209 stream-gaging stations and 8 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 39 stream-gaging stations and partial record sites, 18 lakes sites, and 395 groundwater wells; and water levels for 425 observation network wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.
NASA Technical Reports Server (NTRS)
Kahn, R.
1985-01-01
The consequences of the hypothesis that the evolution of CO2 is directly linked to the occurrence of at least transitory pockets of moisture were exposed. The current conditions preclude the existence of open bodies of liquid water and the formation of moisture in disequilibrium is not excluded by any known constraints. The water evaporation rate is inversely proportional to PCO2, and the existence of a limiting value (P*) for which liquid water can form in the Mars environment is postulated. The evolution of PCO2 is controlled largely by relatively rapid aqueous chemistry forming carbon-containing sedimentary rocks, perhaps during early history in open water, but more recently in transitory pockets of moisture in the soil. Once the total atmospheric pressure is reduced to near P*, the occurrence of transitory moisture is inhibited, and atmospheric CO2 is no longer depleted by an efficient mechanism. The role of the carbonate reservoir in the current overall carbon budget on Mars, according to this scheme, is illustrated.
Kostoglou, M; Varka, E-M; Kalogianni, E P; Karapantsios, T D
2010-09-01
Destabilization of hexane-in-water emulsions is studied by a continuous, non-intrusive, multi-probe, electrical conductance technique. Emulsions made of different oil fractions and surfactant (C(10)E(5)) concentrations are prepared in a stirred vessel using a Rushton turbine to break and agitate droplets. During the separation of phases, electrical signals from pairs of ring electrodes mounted at different heights onto the vessel wall, are recorded. The evolution of the local water volume fractions at the locations of the electrodes is estimated from these signals. It is found that in the absence of coalescence, the water fraction evolution curve from the bottom pair of electrodes is compatible with a bidisperse oil droplet size distribution. The sizes and volume fractions of the two droplet modes are estimated using theoretical arguments. The electrically determined droplet sizes are compared to data from microscopy image analysis. Results are discussed in detail. Copyright 2010 Elsevier Inc. All rights reserved.
Gossell, M A; Nishikawa, T; Hanson, R T; Izbicki, J A; Tabidian, M A; Bertine, K
1999-01-01
Ground water production wells commonly are designed to maximize well yield and, therefore, may be screened over several water-bearing zones. These water-bearing zones usually are identified, and their hydrogeologic characteristics and water quality are inferred, on the basis of indirect data such as geologic and geophysical logs. Production well designs based on these data may result in wells that are drilled deeper than necessary and are screened through zones having low permeability or poor-quality ground water. In this study, we examined the application of flowmeter logging and depth-dependent water quality samples for the improved design of production wells in a complex hydrogeologic setting. As a demonstration of these techniques, a flowmeter log and depth-dependent water quality data were collected from a long-screened production well within a multilayered coastal aquifer system in the Santa Clara-Calleguas Basin, Ventura County, California. Results showed that the well yields most of its water from four zones that constitute 58% of the screened interval. The importance of these zones to well yield was not readily discernible from indirect geologic or geophysical data. The flowmeter logs and downhole water quality data also show that small quantities of poor-quality water could degrade the overall quality of water from the well. The data obtained from one well can be applied to other proposed wells in the same hydrologic basin. The application of flowmeter and depth-dependent water quality data to well design can reduce installation costs and improve the quantity and quality of water produced from wells in complex multiple-aquifer systems.
Gossell, M.A.; Nishikawa, Tracy; Hanson, Randall T.; Izbicki, John A.; Tabidian, M.A.; Bertine, K.
1999-01-01
Ground water production wells commonly are designed to maximize well yield and, therefore, may be screened over several water-bearing zones. These water-bearing zones usually are identified, and their hydrogeologic characteristics and water quality are inferred, on the basis of indirect data such as geologic and geophysical logs. Production well designs based on these data may result in wells that are drilled deeper than necessary and are screened through zones having low permeability or poor-quality ground water. In this study, we examined the application of flowmeter logging and depth-dependent water quality samples for the improved design of production wells in a complex hydrogeologic setting. As a demonstration of these techniques, a flowmeter log and depth-dependent water quality data were collected from a long-screened production well within a multilayered coastal aquifer system in the Santa Clara-Calleguas Basin, Ventura County, California. Results showed that the well yields most of its water from four zones that constitute 58% of the screened interval. The importance of these zones to well yield was not readily discernible from indirect geologic or geophysical data. The flowmeter logs and downhole water quality data also show that small quantities of poor-quality water could degrade the overall quality of water from the well. The data obtained from one well can be applied to other proposed wells in the same hydrologic basin. The application of flowmeter and depth-dependent water quality data to well design can reduce installation costs and improve the quantity and quality of water produced from wells in complex multiple-aquifer systems.
Investigating Drought Onset, Termination and Recovery According to Water Quality Indicators
NASA Astrophysics Data System (ADS)
Ahmadi, B.; Moradkhani, H.
2016-12-01
Frequency and severity of droughts are increasing globally. Reduced catchment runoff and river flows caused by the meteorological drivers leads to hydrological drought. Hydrological droughts have significant impacts not only on water quantity but also on water quality. In this study, first the onset of historical hydrological droughts is estimated using daily threshold-based indicators. Then drought termination and recovery period in terms of water quantity is analyzed. This is followed by examination of water quality during these detected hydrological droughts. Four water quality parameters, i.e., water temperature, dissolved oxygen, pH and turbidity are investigated over Willamette river basin located in northwestern Oregon in the United States. Drought vulnerability and resiliency are analyzed for the study period. Droughts and the recovery period are found to have significant impact on water quality parameters. Also, the results indicate a deterioration of water quality during droughts and longer drought recovery if water quality indicators are considered in the analysis.
Water Quality Assessment of Danjiangkou Reservoir and its Tributaries in China
NASA Astrophysics Data System (ADS)
Liu, Linghua; Peng, Wenqi; Wu, Leixiang; Liu, Laisheng
2018-01-01
Danjiangkou Reservoir is an important water source for the middle route of the South to North Water Diversion Project in China, and water quality of Danjiangkou Reservoir and its tributaries is crucial for the project. The purpose of this study is to evaluate the water quality of Daniiangkou Reservoir and its tributaries based on Canadian Council of Ministers of the Environment Water Quality Index (CCMEWQI). 22 water quality parameters from 25 sampling sites were analyzed to calculate WQI. The results indicate that water quality in Danjiangkou Reservoir area, Hanjiang River and Danjiang River is excellent. And the seriously polluted tributary rivers were Shending River, Jianghe River, Sihe River, Tianhe River, Jianhe River and Jiangjun River. Water quality parameters that cannot meet the standard limit for drinking water source were fecal coliform bacteria, CODcr, CODMn, BOD5, NH3-N, TP, DO, anionic surfactant and petroleum. Fecal coliform bacteria, TP, ammonia nitrogen, CODMn were the most common parameters to fail.
Mass imbalances in EPANET water-quality simulations
NASA Astrophysics Data System (ADS)
Davis, Michael J.; Janke, Robert; Taxon, Thomas N.
2018-04-01
EPANET is widely employed to simulate water quality in water distribution systems. However, in general, the time-driven simulation approach used to determine concentrations of water-quality constituents provides accurate results only for short water-quality time steps. Overly long time steps can yield errors in concentration estimates and can result in situations in which constituent mass is not conserved. The use of a time step that is sufficiently short to avoid these problems may not always be feasible. The absence of EPANET errors or warnings does not ensure conservation of mass. This paper provides examples illustrating mass imbalances and explains how such imbalances can occur because of fundamental limitations in the water-quality routing algorithm used in EPANET. In general, these limitations cannot be overcome by the use of improved water-quality modeling practices. This paper also presents a preliminary event-driven approach that conserves mass with a water-quality time step that is as long as the hydraulic time step. Results obtained using the current approach converge, or tend to converge, toward those obtained using the preliminary event-driven approach as the water-quality time step decreases. Improving the water-quality routing algorithm used in EPANET could eliminate mass imbalances and related errors in estimated concentrations. The results presented in this paper should be of value to those who perform water-quality simulations using EPANET or use the results of such simulations, including utility managers and engineers.
Panthi, Jeeban; Li, Fengting; Wang, Hongtao; Aryal, Suman; Dahal, Piyush; Ghimire, Sheila; Kabenge, Martin
2017-06-01
Both climatic and non-climatic factors affect surface water quality. Similar to its effect across various sectors and areas, climate change has potential to affect surface water quality directly and indirectly. On the one hand, the rise in temperature enhances the microbial activity and decomposition of organic matter in the river system and changes in rainfall alter discharge and water flow in the river ultimately affecting pollution dilution level. On the other hand, the disposal of organic waste and channelizing municipal sewage into the rivers seriously worsen water quality. This study attempts to relate hydro-climatology, water quality, and impact of climatic and non-climatic stresses in affecting river water quality in the upper Bagmati basin in Central Nepal. The results showed that the key water quality indicators such as dissolved oxygen and chemical oxygen demand are getting worse in recent years. No significant relationships were found between the key water quality indicators and changes in key climatic variables. However, the water quality indicators correlated with the increase in urban population and per capita waste production in the city. The findings of this study indicate that dealing with non-climatic stressors such as reducing direct disposal of sewerage and other wastes in the river rather than emphasizing on working with the effects from climate change would largely help to improve water quality in the river flowing from highly populated urban areas.
Lu, Yan; He, Tian
2014-09-15
Much attention has been recently paid to ex-post assessments of socioeconomic and environmental benefits of payment for ecosystem services (PES) programs on poverty reduction, water quality, and forest protection. To evaluate the effects of a regional PES program on water quality, we selected chemical oxygen demand (COD) and ammonia-nitrogen (NH3-N) as indicators of water quality. Statistical methods and an intervention analysis model were employed to assess whether the PES program produced substantial changes in water quality at 10 water-quality sampling stations in the Shaying River watershed, China during 2006-2011. Statistical results from paired-sample t-tests and box plots of COD and NH3-N concentrations at the 10 stations showed that the PES program has played a positive role in improving water quality and reducing trans-boundary water pollution in the Shaying River watershed. Using the intervention analysis model, we quantitatively evaluated the effects of the intervention policy, i.e., the watershed PES program, on water quality at the 10 stations. The results suggest that this method could be used to assess the environmental benefits of watershed or water-related PES programs, such as improvements in water quality, seasonal flow regulation, erosion and sedimentation, and aquatic habitat. Copyright © 2014 Elsevier B.V. All rights reserved.
Solberg, Patricia A.; Moore, Bryan; Blacklock, Ty D.
2012-01-01
Population growth and changes in land use have the potential to affect water quality and quantity in the upper Gunnison River Basin. In 1995, the U.S. Geological Survey (USGS), in cooperation with the Bureau of Land Management, City of Gunnison, Colorado River Water Conservation District, Crested Butte South Metropolitan District, Gunnison County, Hinsdale County, Mount Crested Butte Water and Sanitation District, National Park Service, Town of Crested Butte, U.S. Forest Service, Upper Gunnison River Water Conservancy District, and Western State College, established a water-quality monitoring program in the upper Gunnison River Basin to characterize current water-quality conditions and to assess the effects of increased urban development and other land-use changes on water quality. The monitoring network has evolved into two groups of sites: (1) sites that are considered long term and (2) sites that are considered rotational. Data from the long-term sites assist in defining temporal changes in water quality (how conditions may change over time). The rotational sites assist in the spatial definition of water-quality conditions (how conditions differ throughout the basin) and address local and short-term concerns. Biannual summaries of the water-quality data from the monitoring network provide a point of reference for stakeholder discussions regarding the location and purpose of water-quality monitoring sites in the upper Gunnison River Basin. This report compares and summarizes the data collected during water years 2008 and 2009 to the historical data available at these sites. The introduction provides a map of the sampling sites, definitions of terms, and a one-page summary of selected water-quality conditions at the network sites. The remainder of the report is organized around the data collected at individual sites. Data collected during water years 2008 and 2009 are compared to historical data, State water-quality standards, and Federal water-quality guidelines. A seasonal Kendall test for trend analysis is completed when there is sufficient data (typically >5 years) at the station. Data were collected following USGS protocols.
Geochemical evolution of solutions derived from experimental weathering of sulfide-bearing rocks
Munk, L.; Faure, G.; Koski, R.
2006-01-01
The chemical composition of natural waters is affected by the weathering of geologic materials at or near the surface of the Earth. Laboratory weathering experiments of whole-rock sulfide rocks from the Shoe-Basin Mine (SBM) and the Pennsylvania Mine (PM) from the Peru Creek Basin, Summit County, Colorado, indicate that the mineral composition of the sulfide rocks, changes in pH, the duration of the experiment, and the formation of sorbents such as Fe and Al oxyhydroxides affect the chemical composition of the resulting solution. Carbonate minerals in the rock from SBM provide buffering capacity to the solution, contribute to increases in the pH and enhance the formation of Fe and Al oxyhydroxides, which sorb cations from solution. The final solution pH obtained in the experiments was similar to those measured in the field (i.e., 2.8 for PM and 5.0 for SBM). At PM, acidic, metal-rich mine effluent is discharged into Peru Creek where it mixes with stream water. As a result, the pH of the effluent increases causing Fe and Al oxyhydroxide and schwertmannite to precipitate. The resulting solids sorb metal cations from the water thereby improving the quality of the water in Peru Creek. ?? 2006.
Duque-Ramos, Astrid; Quesada-Martínez, Manuel; Iniesta-Moreno, Miguela; Fernández-Breis, Jesualdo Tomás; Stevens, Robert
2016-10-17
The biomedical community has now developed a significant number of ontologies. The curation of biomedical ontologies is a complex task and biomedical ontologies evolve rapidly, so new versions are regularly and frequently published in ontology repositories. This has the implication of there being a high number of ontology versions over a short time span. Given this level of activity, ontology designers need to be supported in the effective management of the evolution of biomedical ontologies as the different changes may affect the engineering and quality of the ontology. This is why there is a need for methods that contribute to the analysis of the effects of changes and evolution of ontologies. In this paper we approach this issue from the ontology quality perspective. In previous work we have developed an ontology evaluation framework based on quantitative metrics, called OQuaRE. Here, OQuaRE is used as a core component in a method that enables the analysis of the different versions of biomedical ontologies using the quality dimensions included in OQuaRE. Moreover, we describe and use two scales for evaluating the changes between the versions of a given ontology. The first one is the static scale used in OQuaRE and the second one is a new, dynamic scale, based on the observed values of the quality metrics of a corpus defined by all the versions of a given ontology (life-cycle). In this work we explain how OQuaRE can be adapted for understanding the evolution of ontologies. Its use has been illustrated with the ontology of bioinformatics operations, types of data, formats, and topics (EDAM). The two scales included in OQuaRE provide complementary information about the evolution of the ontologies. The application of the static scale, which is the original OQuaRE scale, to the versions of the EDAM ontology reveals a design based on good ontological engineering principles. The application of the dynamic scale has enabled a more detailed analysis of the evolution of the ontology, measured through differences between versions. The statistics of change based on the OQuaRE quality scores make possible to identify key versions where some changes in the engineering of the ontology triggered a change from the OQuaRE quality perspective. In the case of the EDAM, this study let us to identify that the fifth version of the ontology has the largest impact in the quality metrics of the ontology, when comparative analyses between the pairs of consecutive versions are performed.
Water-Quality Assessment of the High Plains Aquifer, 1999-2004
McMahon, Peter B.; Dennehy, Kevin F.; Bruce, Breton W.; Gurdak, Jason J.; Qi, Sharon L.
2007-01-01
Water quality of the High Plains aquifer was assessed for the period 1999-2004 as part of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program. This effort represents the first systematic regional assessment of water quality in this nationally important aquifer. A stratified, nested group of studies was designed to assess linkages between the quality of water recharging the aquifer, the effect of transport through the hydrologic system on water quality, and the quality of the resource used for human consumption and agricultural applications. The stratified, nested design facilitated upscaling of monitoring results to unmonitored areas of the aquifer as well as upscaling of process understanding from local to regional scales.
Migrating microbes: what pathogens can tell us about population movements and human evolution.
Houldcroft, Charlotte J; Ramond, Jean-Baptiste; Rifkin, Riaan F; Underdown, Simon J
2017-08-01
The biology of human migration can be observed from the co-evolutionary relationship with infectious diseases. While many pathogens are brief, unpleasant visitors to human bodies, others have the ability to become life-long human passengers. The story of a pathogen's genetic code may, therefore, provide insight into the history of its human host. The evolution and distribution of disease in Africa is of particular interest, because of the deep history of human evolution in Africa, the presence of a variety of non-human primates, and tropical reservoirs of emerging infectious diseases. This study explores which pathogens leave traces in the archaeological record, and whether there are realistic prospects that these pathogens can be recovered from sub-Saharan African archaeological contexts. Three stories are then presented of germs on a journey. The first is the story of HIV's spread on the back of colonialism and the railway networks over the last 150 years. The second involves the spread of Schistosoma mansoni, a parasite which shares its history with the trans-Atlantic slave trade and the origins of fresh-water fishing. Finally, we discuss the tantalising hints of hominin migration and interaction found in the genome of human herpes simplex virus 2. Evidence from modern African pathogen genomes can provide data on human behaviour and migration in deep time and contribute to the improvement of human quality-of-life and longevity.
Evolution of biodegradation of deinking by-products used as alternative cover material.
Aït-Benichou, Samah; Rodrigues Cabral, Alexandre; Teixeira Panarotto, Claudia
2008-01-01
Deinking by-products (DBP) have been used as alternative cover material for landfills and mine tailings. Since DBP is biodegradable because of its high cellulose and hemicellulose content, a laboratory experimental program was performed to monitor the evolution of biodegradation and changes in the physico-chemical and geotechnical properties of DBP samples submitted to accelerated biodegradation for 1460 days at 38 degrees C. The evolution of gas and leachate production was monitored in terms of both quality and quantity, which allowed for the calculation of mass loss with time. Under the conditions of the tests (no load applied), 19.6% of the mass was lost as gas, whereas 6.1% was leached out. The results show that biodegradation did not significantly alter the compaction behavior of DBP. The void ratio and water content increased significantly, while the volume of the samples slightly decreased. This seem to indicate that the porous structure of the samples was no longer the same after 1460 d of accelerated biodegradation. A slight increase in the relative density indicates that the organic/inorganic matter ratio increased. The results of permeability tests performed with samples at various stages of biodegradation and at various confining stresses show that the saturated hydraulic conductivity of recompacted biodegraded DBP decreased from 7 x 10(-7)cm/s to approximately 2 x 10(-7)cm/s, as biodegradation advanced.
NASA Astrophysics Data System (ADS)
Eslami, Babak; López-Guerra, Enrique A.; Raftari, Maryam; Solares, Santiago D.
2016-04-01
Addition of a strong base to Nafion® proton exchange membranes is a common practice in industry to increase their overall performance in fuel cells. Here, we investigate the evolution of the nano-rheological properties of Nafion thin films as a function of the casting pH, via characterization with static and dynamic, contact and intermittent-contact atomic force microscopy (AFM) techniques. The addition of KOH causes non-monotonic changes in the viscoelastic properties of the films, which behave as highly dissipative, softer materials near neutral pH values, and as harder, more elastic materials at extreme pH values. We quantify this behavior through calculation of the temporal evolution of the compliance and the glassy compliance under static AFM measurements. We complement these observations with dynamic AFM metrics, including dissipated power and virial (for intermittent-contact-mode measurements), and contact resonance frequency and quality factor (for dynamic contact-mode measurements). We explain the non-monotonic material property behavior in terms of the degree of ionic crosslinking and moisture content of the films, which vary with the addition of KOH. This work focuses on the special case study of the addition of strong bases, but the observed mechanical property changes are broadly related to water plasticizing effects and ionic crosslinking, which are also important in other types of films.
Zhu, Mingchao; Zhang, Zhongyi; Zhang, Hu; Zhang, Hui; Zhang, Xiaodong; Zhang, Lixue; Wang, Shicai
2018-01-01
Hydrophilic medium and precursors were used to synthesize a hydrophilic electro-catalyst for overall water splitting. The cobalt sulfide (Co 3 S 4 ) catalyst exhibits a layered nanosheet structure with a hydrophilic surface, which can facilitate the diffusion of aqueous substrates into the electrode pores and towards the active sites. The Co 3 S 4 catalyst shows excellent bifunctional catalytic activity for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline solution. The assembled water electrolyzer based on Co 3 S 4 exhibits better performance and stability than that of Pt/C-RuO 2 catalyst. Thereforce the hydrophilic Co 3 S 4 is a highly promising bifunctional catalyst for the overall water splitting reaction. Copyright © 2017 Elsevier Inc. All rights reserved.
Littin, Gregory R.
2012-01-01
The Cedar River alluvial aquifer is the primary source of municipal water in the Cedar Rapids, Iowa area. Municipal wells are completed in the alluvial aquifer approximately 40 to 80 feet below land surface. The City of Cedar Rapids and the U.S. Geological Survey have been conducting a cooperative study of the groundwater-flow system and water quality of the aquifer since 1992. Cooperative reports between the City of Cedar Rapids and the U.S. Geological Survey have documented hydrologic and water-quality data, geochemistry, and groundwater models. Water-quality samples were collected for studies involving well field monitoring, trends, source-water protection, groundwater geochemistry, surface-water-groundwater interaction, and pesticides in groundwater and surface water. Water-quality analyses were conducted for major ions (boron, bromide, calcium, chloride, fluoride, iron, magnesium, manganese, potassium, silica, sodium, and sulfate), nutrients (ammonia as nitrogen, nitrite as nitrogen, nitrite plus nitrate as nitrogen, and orthophosphate as phosphorus), dissolved organic carbon, and selected pesticides including two degradates of the herbicide atrazine. Physical characteristics (alkalinity, dissolved oxygen, pH, specific conductance and water temperature) were measured in the field and recorded for each water sample collected. This report presents the results of routine water-quality data-collection activities from January 2006 through December 2010. Methods of data collection, quality-assurance, and water-quality analyses are presented. Data include the results of water-quality analyses from quarterly sampling from monitoring wells, municipal wells, and the Cedar River.
Loubet, Philippe; Roux, Philippe; Guérin-Schneider, Laetitia; Bellon-Maurel, Véronique
2016-03-01
A framework and an associated modeling tool to perform life cycle assessment (LCA) of urban water system, namely the WaLA model, has been recently developed. In this paper, the WaLA model is applied to a real case study: the urban water system of the Paris suburban area, in France. It aims to verify the capacity of the model to provide environmental insights to stakeholder's issues related to future trends influencing the system (e.g., evolution of water demand, increasing water scarcity) or policy responses (e.g., choices of water resources and technologies). This is achieved by evaluating a baseline scenario for 2012 and several forecasting scenarios for 2022 and 2050. The scenarios are designed through the modeling tool WaLA, which is implemented in Simulink/Matlab: it combines components representing the different technologies, users and resources of the UWS. The life cycle inventories of the technologies and users components include water quantity and quality changes, specific operation (electricity, chemicals) and infrastructures data (construction materials). The methods selected for the LCIA are midpoint ILCD, midpoint water deprivation impacts at the sub-river basin scale, and endpoint Impact 2002+. The results of the baseline scenario show that wastewater treatment plants have the highest impacts compared to drinking water production and distribution, as traditionally encountered in LCA of UWS. The results of the forecasting scenarios show important changes in water deprivation impacts due to water management choices or effects of climate change. They also enable to identify tradeoffs with other impact categories and to compare several scenarios. It suggests the capacity of the model to deliver information for decision making about future policies. Copyright © 2015 Elsevier Ltd. All rights reserved.
40 CFR 131.35 - Colville Confederated Tribes Indian Reservation.
Code of Federal Regulations, 2011 CFR
2011-07-01
...-effective and reasonable best management practices for nonpoint source control. (iii) Where high quality... within areas designated as unique water quality management areas and waters otherwise of exceptional... PROGRAMS WATER QUALITY STANDARDS Federally Promulgated Water Quality Standards § 131.35 Colville...
NASA Technical Reports Server (NTRS)
Sauer, R. L.; Calley, D. J.
1975-01-01
The history and evolution of the Apollo potable water system is reviewed. Its operation in the space environment and in the spacecraft is described. Its performance is evaluated. The Apollo potable water system satisfied the dual purpose of providing metabolic water for the crewmen and water for spacecraft cooling.
Management of source and drinking-water quality in Pakistan.
Aziz, J A
2005-01-01
Drinking-water quality in both urban and rural areas of Pakistan is not being managed properly. Results of various investigations provide evidence that most of the drinking-water supplies are faecally contaminated. At places groundwater quality is deteriorating due to the naturally occurring subsoil contaminants or to anthropogenic activities. The poor bacteriological quality of drinking-water has frequently resulted in high incidence of waterborne diseases while subsoil contaminants have caused other ailments to consumers. This paper presents a detailed review of drinking-water quality in the country and the consequent health impacts. It identifies various factors contributing to poor water quality and proposes key actions required to ensure safe drinking-water supplies to consumers.
Water-quality assessment of the Cook Inlet basin, Alaska : summary of data through 1997
Glass, Roy L.
1999-01-01
Among the first activities undertaken in each National Water-Quality Assessment (NAWQA) investigation are the compilation, screening, and statistical summary of available data concerning water-quality conditions in the study unit. The water-quality conditions of interest are those that are representative of the general ambient water quality of a given stream reach or area of an aquifer. This report identifies which existing water-quality data are suitable for characterizing general conditions in a nationally consistent manner and describes, to the extent possible, general water-quality conditions in the Cook Inlet Basin in southcentral Alaska. The study unit consists of all lands that drain into Cook Inlet, but not the marine environment itself. Surface-water-quality data are summarized for 31 sites on streams. Ground-water quality data are summarized for four regions using analyses from about 550 wells that yield water from unconsolidated glacial and alluvial deposits and analyses from 17 wells in western Cook Inlet, some of which may yield water from coal or weakly consolidated sandstone or conglomerate. The summaries focus on the central tendencies and typical variations in the data and use nonparametric statistics such as frequencies and percentile values. Few surface- and ground-water sites have long-term water-quality records and very few data are available for dissolved oxygen, nutrients, metals, trace elements, organic compounds, and radionuclides. In general, most waters in streams and wells have small concentrations of major inorganic constituents, nutrients, trace elements, and organic compounds. Most streams have water that is generally suitable for drinking-water supply, the growth and propagation of cold-water anadromous fish, and water-contact recreation. However, suspended-sediment concentrations in glacier-fed streams are naturally high and can make water from glacier-fed streams unsuitable for many uses unless the water is treated to remove the suspended sediment. Several streams and lakes in Anchorage have fecal coliform bacteria concentrations higher than allowed for drinking or water-contact recreation. Ground water in the major withdrawal regions is generally suitable for drinking and most other purposes, but some wells yield water having nitrate, iron, or arsenic concentrations higher than drinking-water criteria. Ground-water quality has been degraded in several areas as the result of leaks or spills of petroleum products.
The effect of land use change on water quality: A case study in Ciliwung Watershed
NASA Astrophysics Data System (ADS)
Ayu Permatasari, Prita; Setiawan, Yudi; Nur Khairiah, Rahmi; Effendi, Hefni
2017-01-01
Ciliwung is the biggest river in Jakarta. It is 119 km long with a catchment area of 476 km2. It flows from Bogor Regency and crosses Bogor City, Depok City, and Jakarta before finally flowing into Java Sea through Jakarta Bay. The water quality in Ciliwung River has degraded. Many factors affect water quality. Understanding the relationship between land use and surface water quality is necessary for effective water management. It has been widely accepted that there is a close relationship between the land use type and water quality. This study aims to analyze the influence of various land use types on the water quality within the Ciliwung Watershed based on the water quality monitoring data and remote sensing data in 2010 and 2014. Water quality parameters exhibited significant variations between the urban-dominated and forest-dominated sites. The proportion of urban land was strongly positively associated with total nitrogen and ammonia nitrogen concentrations. The result can provide scientific reference for the local land use optimization and water pollution control and guidance for the formulation of policies to coordinate the exploitation and protection of the water resource.
NASA Astrophysics Data System (ADS)
Lallahem, S.; Hani, A.
2017-02-01
Water sustainability in the lower Seybouse River basin, eastern Algeria, must take into account the importance of water quantity and quality integration. So, there is a need for a better knowledge and understanding of the water quality determinants of groundwater abstraction to meet the municipal and agricultural uses. In this paper, the artificial neural network (ANN) models were used to model and predict the relationship between groundwater abstraction and water quality determinants in the lower Seybouse River basin. The study area chosen is the lower Seybouse River basin and real data were collected from forty five wells for reference year 2006. Results indicate that the feed-forward multilayer perceptron models with back-propagation are useful tools to define and prioritize the important water quality parameters of groundwater abstraction and use. The model evaluation shows that the correlation coefficients are more than 95% for training, verification and testing data. The model aims to link the water quantity and quality with the objective to strengthen the Integrated Water Resources Management approach. It assists water planners and managers to better assess the water quality parameters and progress towards the provision of appropriate quantities of water of suitable quality.
Lithological Influences on Occurrence of High-Fluoride Waters in The Central Kenya Rift
NASA Astrophysics Data System (ADS)
Olaka, L. A.; Musolff, A.; Mulch, A.; Olago, D.; Odada, E. O.
2013-12-01
Within the East African rift, groundwater recharge results from the complex interplay of geology, land cover, geomorphology, climate and on going volcano-tectonic processes across a broad range of spatial and temporal scales. The interrelationships between these factors create complex patterns of water availability, reliability and quality. The hydrochemical evolution of the waters is further complex due to the different climatic regimes and geothermal processes going on in this area. High fluoridic waters within the rift have been reported by few studies, while dental fluorosis is high among the inhabitants of the rift. The natural sources of fluoride in waters can be from weathering of fluorine bearing minerals in rocks, volcanic or fumarolic activities. Fluoride concentration in water depends on a number of factors including pH, temperature, time of water-rock formation contact and geochemical processes. Knowledge of the sources and dispersion of fluoride in both surface and groundwaters within the central Kenya rift and seasonal variations between wet and dry seasons is still poor. The Central Kenya rift is marked by active tectonics, volcanic activity and fumarolic activity, the rocks are majorly volcanics: rhyolites, tuffs, basalts, phonolites, ashes and agglomerates some are highly fractured. Major NW-SE faults bound the rift escarpment while the rift floor is marked by N-S striking faults We combine petrographic, hydrochemistry and structural information to determine the sources and enrichment pathways of high fluoridic waters within the Naivasha catchment. A total of 120 water samples for both the dry season (January-February2012) and after wet season (June-July 2013) from springs, rivers, lakes, hand dug wells, fumaroles and boreholes within the Naivasha catchment are collected and analysed for fluoride, physicochemical parameters and stable isotopes (δ2 H, δ18 O) in order to determine the origin and evolution of the waters. Additionally, 30 soil and rock samples were also collected and analysed for fluoride, and rock samples were subjected to petrographic investigations and X-ray diffraction. The fluoride levels in surface and groundwater for the dry season range from 0.019 - 50.14 mg/L, on average above the WHO permissible limit. The high fluoride occurs both in the lake and groundwater. Preliminary petrographic studies show considerable fluoride in micas. The study is on-going and plans to present the relative abundances of fluoride in the lithology as the sources and the fluoride enrichment pathways of the groundwater within the Central Kenya rift.
Real time monitoring of water distribution in an operando fuel cell during transient states
NASA Astrophysics Data System (ADS)
Martinez, N.; Peng, Z.; Morin, A.; Porcar, L.; Gebel, G.; Lyonnard, S.
2017-10-01
The water distribution of an operating proton exchange membrane fuel cell (PEMFC) was monitored in real time by using Small Angle Neutron Scattering (SANS). The formation of liquid water was obtained simultaneously with the evolution of the water content inside the membrane. Measurements were performed when changing current with a time resolution of 10 s, providing insights on the kinetics of water management prior to the stationary phase. We confirmed that water distribution is strongly heterogeneous at the scale at of the whole Membrane Electrode Assembly. As already reported, at the local scale there is no straightforward link between the amounts of water present inside and outside the membrane. However, we show that the temporal evolutions of these two parameters are strongly correlated. In particular, the local membrane water content is nearly instantaneously correlated to the total liquid water content, whether it is located at the anode or cathode side. These results can help in optimizing 3D stationary diphasic models used to predict PEMFC water distribution.
Wang, Juan; Yuan, Chengqian; Han, Yuchun; Wang, Yilin; Liu, Xiaomin; Zhang, Suojiang; Yan, Xuehai
2017-11-01
The interaction between water and biomolecules including peptides is of critical importance for forming high-level architectures and triggering life's functions. However, the bulk aqueous environment has limitations in detecting the kinetics and mechanisms of peptide self-assembly, especially relating to interactions of trace water. With ionic liquids (ILs) as a nonconventional medium, herein, it is discovered that trace amounts of water play a decisive role in triggering self-assembly of a biologically derived dipeptide. ILs provide a suitable nonaqueous environment, enabling us to mediate water content and follow the dynamic evolution of peptide self-assembly. The trace water is found to be involved in the assembly process of dipeptide, especially leading to the formation of stable noncovalent dipeptide oligomers in the early stage of nucleation, as evident by both experimental studies and theoretical simulations. The thermodynamics of the growth process is mainly governed by a synergistic effect of hydrophobic interaction and hydrogen bonds. Each step of assembly presents a different trend in thermodynamic energy. The dynamic evolution of assembly process can be efficiently mediated by changing trace water content. The decisive role of trace water in triggering and mediating self-assembly of biomolecules provides a new perspective in understanding supramolecular chemistry and molecular self-organization in biology. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Speltini, Andrea; Sturini, Michela; Dondi, Daniele; Annovazzi, Enrico; Maraschi, Federica; Caratto, Valentina; Profumo, Antonella; Buttafava, Armando
2014-10-01
This work presents a systematic study of cellulose (CLS) as a sacrificial biomass for photocatalytic H2 evolution from water. The idea is indeed to couple a largely available and not expensive biomass, and water, with a renewable energy like solar radiation. An aqueous CLS suspension irradiated either at 366 nm (UV-A) or under sunlight in the presence of Pt/TiO2 behaves as a H2 evolving system. The effects of irradiation time, catalyst and CLS concentrations, pH and water salinity are studied. Addition of CLS to the sample significantly improved H2 evolution from water splitting, with yields up to ten fold higher than those observed in neat water. The mechanism of the photocatalytic process relies on the TiO2-mediated CLS hydrolysis, under irradiation. The polysaccharide depolymerisation generates water-soluble species and intermediates, among them 5-hydroxymethylfurfural (HMF) was identified. These intermediates are readily oxidized following the glucose photoreforming, thus enhancing water hydrogen ion reduction to give gas-phase H2. The formation of "colored" by-products from HMF self-polymerization involves a sort of "in situ dye sensitization" that allows an effective photoreaction even under solar light. The procedure is evaluated and successfully extended on cellulosic biomasses, i.e. rice husk and alfalfa (Medicago sativa) stems, not previously investigated for this application.
Water Resources Data for California, 1969; Part 2: Water Quality Records
1970-01-01
Water-resources investigations of the U.S. Geological Survey include the collection of water-quality data on the chemical and physical characteristics of surface and ground-water supplies of the Nation. Theses data for the 1969 water year for the quality of surface water in California are presented in this report. Data for a few water-quality stations in bordering States are also included. The data were collected by the Water Resources Division of the Geological Survey under the direction of R. Stanley Lord, district chief, Menlo Park, Calif.
NASA Astrophysics Data System (ADS)
Cao, Yingjie; Tang, Changyuan; Song, Xianfang; Liu, Changming; Zhang, Yinghua
2016-06-01
Two multivariate statistical technologies, factor analysis (FA) and discriminant analysis (DA), are applied to study the river and groundwater hydrochemistry and its controlling processes in the Sanjiang Plain of the northeast China. Factor analysis identifies five factors which account for 79.65 % of the total variance in the dataset. Four factors bearing specific meanings as the river and groundwater hydrochemistry controlling processes are divided into two groups, the "natural hydrochemistry evolution" group and the "pollution" group. The "natural hydrochemistry evolution" group includes the salinity factor (factor 1) caused by rock weathering and the residence time factor (factor 2) reflecting the groundwater traveling time. The "pollution" group represents the groundwater quality deterioration due to geogenic pollution caused by elevated Fe and Mn (factor 3) and elevated nitrate (NO3 -) introduced by human activities such as agriculture exploitations (factor 5). The hydrochemical difference and hydraulic connection among rivers (surface water, SW), shallow groundwater (SG) and deep groundwater (DG) group are evaluated by the factor scores obtained from FA and DA (Fisher's method). It is showed that the river water is characterized as low salinity and slight pollution, and the shallow groundwater has the highest salinity and severe pollution. The SW is well separated from SG and DG by Fisher's discriminant function, but the SG and DG can not be well separated showing their hydrochemical similarities, and emphasize hydraulic connections between SG and DG.
An efficient hybrid approach for multiobjective optimization of water distribution systems
NASA Astrophysics Data System (ADS)
Zheng, Feifei; Simpson, Angus R.; Zecchin, Aaron C.
2014-05-01
An efficient hybrid approach for the design of water distribution systems (WDSs) with multiple objectives is described in this paper. The objectives are the minimization of the network cost and maximization of the network resilience. A self-adaptive multiobjective differential evolution (SAMODE) algorithm has been developed, in which control parameters are automatically adapted by means of evolution instead of the presetting of fine-tuned parameter values. In the proposed method, a graph algorithm is first used to decompose a looped WDS into a shortest-distance tree (T) or forest, and chords (Ω). The original two-objective optimization problem is then approximated by a series of single-objective optimization problems of the T to be solved by nonlinear programming (NLP), thereby providing an approximate Pareto optimal front for the original whole network. Finally, the solutions at the approximate front are used to seed the SAMODE algorithm to find an improved front for the original entire network. The proposed approach is compared with two other conventional full-search optimization methods (the SAMODE algorithm and the NSGA-II) that seed the initial population with purely random solutions based on three case studies: a benchmark network and two real-world networks with multiple demand loading cases. Results show that (i) the proposed NLP-SAMODE method consistently generates better-quality Pareto fronts than the full-search methods with significantly improved efficiency; and (ii) the proposed SAMODE algorithm (no parameter tuning) exhibits better performance than the NSGA-II with calibrated parameter values in efficiently offering optimal fronts.
NASA Astrophysics Data System (ADS)
Yunlong, Song; Zhang, Jinsong; Zhu, Jia; Li, Wang; Chang, Aimin; Yi, Tao
2017-12-01
Controlling of water quality pollution and eutrophication of reservoirs has become a very important research topic in urban drinking water field. Xili reservoir is an important water source of drinking water in Shenzhen. And its water quality has played an important role to the city’s drinking water security. A fifteen-month’s field observation was conducted from April 2013 to June 2014 in Xili reservoir, in order to analyze the temporal and spatial distribution of water quality factors and seasonal variation of trophic states. Xili reservoir was seriously polluted by nitrogen. Judged by TN most of the samples were no better than grade VI. Other water quality factor including WT, SD, pH, DO, COD, TOC, TP, Fe, silicate, turbidity, chlorophyll-a were pretty good. One-way ANOVA showed that significant difference was found in water quality factors on month (p<0.005). The spatial heterogeneity of water quality was obvious (p<0.05). The successions of water quality factors y were similar and the mainly pattern was Pre-rainy period > Latter rainy period > High temperature and rain free period > Temperature jump period > Winter drought period. Two-way ANOVA showed that months rather than locations were the key influencing factors of water quality factors succession.TLI (Σ) were about 35~52, suggesting Xili reservoir was in mycotrophic trophic states. As a result of runoff pollution, water quality at sampling sites 1 and 10 was poor. In the rainy season, near sampling sites 1 and 10, water appeared to be Light-eutrophic. The phytoplankton biomass of Xili reservoir was low. Water temperature was the main driving factor of phytoplankton succession.The 14 water quality factors were divided into five groups by factor analysis. The total interpretation rate was about 70.82%. F1 represents the climatic change represented by water temperature and organic pollution. F2 represents the concentration of nitrogen. F3 represents the phytoplankton biomass. F4 represents the sensory indexes of water body, such as turbidity, transparency.
Water Quality in the Great Salt Lake Basins, Utah, Idaho, and Wyoming, 1998-2001
Waddell, Kidd M.; Gerner, Steven J.; Thiros, Susan A.; Giddings, Elise M.; Baskin, Robert L.; Cederberg, Jay R.; Albano, Christine M.
2004-01-01
This report contains the major findings of a 1998-2001 assessment of water quality in the Great Salt Lake Basins. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is discussed in terms of local, State, and regional issues. Conditions in a particular basin or aquifer system are compared to conditions found elsewhere and to selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. This report is intended for individuals working with water-resource issues in Federal, State, or local agencies, universities, public interest groups, or in the private sector. The information will be useful in addressing a number of current issues, such as the effects of agricultural and urban land use on water quality, human health, drinking water, source-water protection, hypoxia and excessive growth of algae and plants, pesticide registration, and monitoring and sampling strategies. This report is also for individuals who wish to know more about the quality of streams and ground water in areas near where they live, and how that water quality compares to water quality in other areas across the Nation. The water-quality conditions in the Great Salt Lake Basins summarized in this report are discussed in detail in other reports that can be accessed at http://ut.water.usgs.gov. Detailed technical information, data and analyses, collection and analytical methodology, models, graphs, and maps that support the findings presented in this report in addition to reports in this series from other basins can be accessed at the national NAWQA Web site http://water.usgs.gov/nawqa.
Water Quality in the Cook Inlet Basin Alaska, 1998-2001
Glass, Roy L.; Brabets, Timothy P.; Frenzel, Steven A.; Whitman, Matthew S.; Ourso, Robert T.
2004-01-01
This report contains the major findings of a 1998?2001 assessment of water quality in the Cook Inlet Basin. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is discussed in terms of local, State, and regional issues. Conditions in a particular basin or aquifer system are compared to conditions found elsewhere and to selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. This report is intended for individuals working with water-resource issues in Federal, State, or local agencies; universities; public interest groups; or in the private sector. The information will be useful in addressing a number of current issues, such as the effects of agricultural and urban land use on water quality, human health, drinking water, source-water protection, hypoxia and excessive growth of algae and plants, pesticide registration, and monitoring and sampling strategies. This report is also for individuals who wish to know more about the quality of streams and ground water in areas near where they live, and how that water quality compares to the quality of water in other areas across the Nation. The water-quality conditions in the Cook Inlet Basin summarized in this report are discussed in detail in other reports that can be accessed at http://ak.water.usgs.gov. Detailed technical information, data and analyses, collection and analytical methodology, models, graphs, and maps that support the findings presented in this report, in addition to reports in this series from other basins, can be accessed from the national NAWQA Web site (http://water.usgs.gov/nawqa).
Water Quality on the Island of Oahu, Hawaii, 1999-2001
Anthony, Stephen S.; Hunt, Charles D.; Brasher, Anne M.D.; Miller, Lisa D.; Tomlinson, Michael S.
2004-01-01
This report contains the major findings of a 1999-2001 assessment of water quality on the island of Oahu, Hawaii. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is discussed in terms of local, State, and regional issues. Conditions in a particular basin or aquifer system are compared to conditions found elsewhere and to selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. This report is intended for individuals working with water-resource issues in Federal, State, or local agencies, universities, public interest groups, or in the private sector. The information will be useful in addressing a number of current issues, such as the effects of agricultural and urban land use on water quality, human health, drinking water, source-water protection, and excessive growth of algae and plants, pesticide registration, and monitoring and sampling strategies. This report is also for individuals who wish to know more about the quality of streams and ground water in areas near where they live, and how that water quality compares to the quality of water in other areas across the Nation. The water-quality conditions on Oahu summarized in this report are discussed in detail in other reports that can be accessed from (http://hi.water.usgs.gov/nawqa). Detailed technical information, data and analyses, collection and analytical methodology, models, graphs, and maps that support the findings presented in this report in addition to reports in this series from other basins can be accessed from the national NAWQA Web site (http://water.usgs.gov/nawqa).
Water Quality in the Upper Illinois River Basin Illinois, Indiana, and Wisconsin, 1999-2001
Groschen, George E.; Arnold, Terri L.; Harris, Mitchell A.; Dupre, David H.; Fitzpatrick, Faith A.; Scudder, Barbara C.; Morrow, William S.; Terrio, Paul J.; Warner, Kelly L.; Murphy, Elizabeth A.
2004-01-01
This report contains the major findings of a 1999?2001 assessment of water quality in the upper Illinois River Basin. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is discussed in terms of local, State, and regional issues. Conditions in a particular basin or aquifer system are compared to conditions found elsewhere and to selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. This report is intended for individuals working with water-resource issues in Federal, State, or local agencies, universities, public-interest groups, or in the private sector. The information will be useful in addressing a number of current issues, such as the effects of agricultural and urban land use on water quality, human health, drinking water, source-water protection, hypoxia and excessive growth of algae and plants, pesticide registration, and monitoring and sampling strategies. This report also is for individuals who wish to know more about the quality of streams and ground water in areas near where they live, and how that water quality compares to the quality of water in other areas across the Nation. The water-quality conditions in the upper Illinois River Basin summarized in this report are discussed in detail in other reports that can be accessed from (http://il.water.usgs.gov/nawqa/uirb). Detailed technical information, data and analyses, collection and analytical methodology, models, graphs, and maps that support the findings presented in this report in addition to reports in this series from other basins can be accessed from the national NAWQA Web site at (http://water.usgs.gov/nawqa).
Water quality in the Northern Rockies Intermontane basins, Idaho, Montana, and Washington, 1999-2001
Clark, Gregory M.; Caldwell, Rodney R.; Maret, Terry R.; Bowers, Craig L.; Dutton, DeAnn M.; Becksmith, Michael A.
2003-01-01
This report contains the major findings of a 1999–2001 assessment of water quality in the Northern Rockies Intermontane Basins. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is discussed in terms of local, State, and regional issues. Conditions in a particular basin or aquifer system are compared to conditions found elsewhere and to selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. This report is intended for individuals working with water-resource issues in Federal, State, or local agencies, universities, public interest groups, or in the private sector. The information will be useful in addressing a number of current issues, such as the effects of agricultural and urban land use on water quality, human health, drinking water, source-water protection, hypoxia and excessive growth of algae and plants, pesticide registration, and monitoring and sampling strategies. This report is also for individuals who wish to know more about the quality of streams and ground water in areas near where they live, and how that water quality compares to the quality of water in other areas across the Nation. The water-quality conditions in the Northern Rockies Intermontane Basins summarized in this report are discussed in detail in other reports that can be accessed from (http://id.water.usgs.gov/nrok/index.html). Detailed technical information, data and analyses, collection and analytical methodology, models, graphs, and maps that support the findings presented in this report in addition to reports in this series from other basins can be accessed from the national NAWQA Web site (http://water.usgs.gov/nawqa).
Water quality in the Yellowstone River Basin, Wyoming, Montana, and North Dakota, 1999-2001
Peterson, David A.; Bartos, Timothy T.; Clark, Melanie L.; Miller, Kirk A.; Porter, Stephen D.; Quinn, Thomas L.
2004-01-01
This report contains the major findings of a 1999?2001 assessment of water quality in the Yellowstone River Basin. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is discussed in terms of local, State, and regional issues. Conditions in a particular basin or aquifer system are compared to conditions found elsewhere and to selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. This report is intended for individuals working with water-resource issues in Federal, State, or local agencies, universities, public interest groups, or in the private sector. The information will be useful in addressing a number of current issues, such as the effects of agricultural and urban land use on water quality, human health, drinking water, source-water protection, hypoxia and excessive growth of algae and plants, pesticide registration, and monitoring and sampling strategies. This report also is for individuals who wish to know more about the quality of streams and ground water in areas near where they live, and how that water quality compares to the quality of water in other areas across the Nation. The water-quality conditions in the Yellowstone River Basin summarized in this report are discussed in detail in other reports that can be accessed from http://wy.water.usgs.gov/YELL/index.htm. Detailed technical information, data and analyses, collection and analytical methodology, models, graphs, and maps that support the findings presented in this report, in addition to reports in this series from other basins, can be accessed from the national NAWQA Web site (http://water.usgs.gov/nawqa).
Stark, J.R.; Andrews, W.J.; Fallon, J.D.; Fong, A.L.; Goldstein, R.M.; Hanson, P.E.; Kroening, S.E.; Lee, K.E.
1996-01-01
Environmental stratification consists of dividing the study unit into subareas with homogeneous characteristics to assess natural and anthropogenic factors affecting water quality. The assessment of water quality in streams and in aquifers is based on the sampling design that compares water quality within homogeneous subareas defined by subbasins or aquifer boundaries. The study unit is stratified at four levels for the surface-water component: glacial deposit composition, surficial geology, general land use and land cover, and secondary land use. Ground-water studies emphasize shallow ground water where quality is most likely influenced by overlying land use and land cover. Stratification for ground-water sampling is superimposed on the distribution of shallow aquifers. For each aquifer and surface-water basin this stratification forms the basis for the proposed sampling design used in the Upper Mississippi River Basin National Water-Quality Assessment.
Water Resources Data North Dakota Water Year 2002 Volume 1. Surface Water
Harkness, R.E.; Lundgren, R.F.; Norbeck, S.W.; Robinson, S.M.; Sether, B.A.
2003-01-01
Water-resources data for the 2002 water year for North Dakota consists of records of discharge, stage, and water quality for streams; contents, stage, and water quality for lakes and reservoirs; and water levels and water quality for ground-water wells. Volume 1 contains records of water discharge for 106 streamflow-gaging stations; stage only for 22 river-stage stations; contents and/or stage for 14 lake or reservoir stations; annual maximum discharge for 35 crest-stage stations; and water-quality for 96 streamflow-gaging stations, 3 river-stage stations, 11 lake or reservoir stations, 8 miscellaneous sample sites on rivers, and 63 miscellaneous sample sites on lakes and wetlands. Data are included for 7 water-quality monitor sites on streams and 2 precipitation-chemistry stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in North Dakota.
Water Resources Data North Dakota Water Year 2003, Volume 1. Surface Water
Robinson, S.M.; Lundgren, R.F.; Sether, B.A.; Norbeck, S.W.; Lambrecht, J.M.
2004-01-01
Water-resources data for the 2003 water year for North Dakota consists of records of discharge, stage, and water quality for streams; contents, stage, and water quality for lakes and reservoirs; and water levels and water quality for ground-water wells. Volume 1 contains records of water discharge for 108 streamflow-gaging stations; stage only for 24 river-stage stations; contents and/or stage for 14 lake or reservoir stations; annual maximum discharge for 32 crest-stage stations; and water-quality for 99 streamflow-gaging stations, 5 river-stage stations, 11 lake or reservoir stations, 8 miscellaneous sample sites on rivers, and 63 miscellaneous sample sites on lakes and wetlands. Data are included for 7 water-quality monitor sites on streams and 2 precipitation-chemistry stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in North Dakota.
Water resources data--North Dakota water year 2005, Volume 1. Surface water
Robinson, S.M.; Lundgren, R.F.; Sether, B.A.; Norbeck, S.W.; Lambrecht, J.M.
2006-01-01
Water-resources data for the 2005 water year for North Dakota consists of records of discharge, stage, and water quality for streams; contents, stage, and water quality for lakes and reservoirs; and water levels and water quality for ground-water wells. Volume 1 contains records of water discharge for 107 streamflow-gaging stations; stage only for 22 river-stage stations; contents and/or stage for 13 lake or reservoir stations; annual maximum discharge for 31 crest-stage stations; and water quality for 93 streamflow-gaging stations, 6 river-stage stations, 15 lake or reservoir stations, and about 50 miscellaneous sample sites on lakes and wetlands. Data are included for 8 water-quality monitor sites on streams and 2 precipitation-chemistry stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in North Dakota.
Water Resources Data North Dakota Water Year 2001, Volume 1. Surface Water
Harkness, R.E.; Berkas, W.R.; Norbeck, S.W.; Robinson, S.M.
2002-01-01
Water-resources data for the 2001 water year for North Dakota consists of records of discharge, stage, and water quality for streams; contents, stage, and water quality for lakes and reservoirs; and water levels and water quality for ground-water wells. Volume 1 contains records of water discharge for 103 streamflow-gaging stations; stage only for 20 river-stage stations; contents and/or stage for 13 lake or reservoir stations; annual maximum discharge for 35 crest-stage stations; and water-quality for 94 streamflow-gaging stations, 2 river-stage stations, 9 lake or reservoir stations, 7 miscellaneous sample sites on rivers, and 58 miscellaneous sample sites on lakes and wetlands. Data are included for 9 water-quality monitor sites on streams and 2 precipitation-chemistry stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in North Dakota.
ERIC Educational Resources Information Center
Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.
The Environmental Quality Instructional Resources Center acquires, reviews, indexes, and announces both print (books, modules, units, etc.) and non-print (films, slides, video tapes, etc.) materials related to water quality and water resources education and instruction. This publication contains abstracts and indexes to selected materials related…
40 CFR Appendix F to Part 132 - Great Lakes Water Quality Initiative Implementation Procedures
Code of Federal Regulations, 2013 CFR
2013-07-01
... aquatic life criteria or values may be developed when: i. The local water quality characteristics such as... 40 Protection of Environment 23 2013-07-01 2013-07-01 false Great Lakes Water Quality Initiative... (CONTINUED) WATER PROGRAMS WATER QUALITY GUIDANCE FOR THE GREAT LAKES SYSTEM Pt. 132, App. F Appendix F to...
Changes in water quality that occur as water flows along hyporheic flow paths may have important effects on surface water quality and aquatic habitat, yet very few studies have examined these hyporheic processes along large gravel bed rivers. To determine water quality changes as...
40 CFR 131.20 - State review and revision of water quality standards.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 22 2011-07-01 2011-07-01 false State review and revision of water quality standards. 131.20 Section 131.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY STANDARDS Procedures for Review and Revision of Water Quality Standards § 131.20 State review and revision of...
Environmental Assessment On-Base Snowmobile Trail at Grand Forks AFB, North Dakota
2004-04-01
Water: Surface water quality could be degraded, both in the short-term, and over the long-term due to reduced storm water quality caused by a potential...Surface water quality could be degraded, both in the short-term, and over the long-term due to reduced storm water quality caused by a potential increase
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gandara, S.C.; Jones, R.E.
1993-11-01
Water-resources data for the 1993 water year for Texas consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains water levels for 771 observation wells and water-quality data for 226 monitoring wells.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gandara, S.C.; Jones, R.E.; Barbie, D.L.
1996-11-22
Water-resources data for the 1996 water year for Texas consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains water levels for 845 observation wells and 187 water-quality data for monitoring wells.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gandara, S.C.; Jones, R.E.
1994-12-12
Water-resources data for the 1994 water year for Texas consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 4 contains water levels for 698 observation wells and water-quality data for 97 monitoring wells.