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Sample records for research catchment north

  1. Collaborative knowledge in catchment research networks

    NASA Astrophysics Data System (ADS)

    Macleod, Christopher Kit

    2015-04-01

    There is a need to improve the production, sharing and use of collaborative knowledge of catchment systems through networks of researchers, policy makers and practitioners. This requires greater levels of systems based integrative research. In parallel to the growing realization that greater levels of collaborative knowledge in scientific research networks are required, a digital revolution has been taking place. This has been driven primarily by the emergence of distributed networks of computers and standards-based interoperability. The objective of this paper is to present the status and research needs for greater levels of systems based integrative research for the production, sharing and use of collaborative knowledge in catchment research networks. To enable increased levels of integrative research depends on development and application of digital technologies to improve collection, use and sharing of data and devise new knowledge infrastructures. This paper focuses on the requirements for catchment observatories that integrate existing and novel physical, social and digital networks of knowledge infrastructures. To support this focus, I present three leading international examples of collaborative networks of catchment researchers and their development of catchment observatories. In particular, the digital infrastructures they have developed to support collaborative knowledge in catchment research networks. These examples are from North America (NSF funded CUAHSI HIS) and from Europe (UK NERC funded EVOp and the German Helmholtz Association Centers funded TERENO/TEODOOR). These exemplars all supported advancing collaborative knowledge in catchment research networks through the development of catchment observatories. I will conclude by discussing the future research directions required for greater levels of production, sharing and use of collaborative knowledge in catchment research networks based on catchment systems science.

  2. Hydro-climatic control of stream water dissolved organic carbon (DOC) across northern catchments within the North-Watch program

    NASA Astrophysics Data System (ADS)

    Laudon, Hjalmar; Tetzlaff, Doerthe; Seibert, Jan; Soulsby, Chris; Carey, Sean; Buttle, Jim; McDonnell, Jeff; McGuire, Kevin; Caissie, Daniel; Shanley, Jamie

    2010-05-01

    There has been an increasing interest in understanding the regulating mechanisms of surface water dissolved organic carbon (DOC) the last decade. A majority of this recent work has been based on individual well characterized research catchments or on regional synoptic datasets combined with readily available landscape and climatic variables. However, as the production and transport of DOC primarily is a function of hydro-climatic conditions a better description of catchment hydrological functioning across large geographic regions would be favorable for moving the mechanistic understanding forward. To do this we report from a first assessment of catchment DOC within the international inter-catchment comparison program North-Watch (http://www.abdn.ac.uk/northwatch/). North-Watch includes long-term research catchments ranging from northern temperate regions to the boreal and sub-arctic biomes with the aim to better understand the variable hydrological and biogeochemical responses in Northern catchments to climate change. The North-Watch catchments are located in Sweden (Krycklan), Scotland (Mharcaidh, Girnock and Strontian), the US (Sleepers River and HJ Andrews) and Canada (Catamaran, Dorset and Wolf Creek). The annual average DOC concentration in the nine catchments investigated were directly linked to hydro-climatic influences (e.g. temperature, water storage) and landscape configuration. In general, the DOC concentration followed a parabolic shape with temperature, where the highest concentrations were found in the boreal and near boreal sites and with the lowest concentrations in the temperate and sub-arctic catchments. The between catchment variability in DOC concentration could also be explained by catchment water storage and amount of wetlands in the catchment. Whereas there is a mechanistic link between long-term climatic conditions and the areal coverage of wetlands, the total catchment storage of water is more strongly linked to topography, parent material

  3. Sediment budget for Rediu reservoir catchment, North-Eastern Romania

    NASA Astrophysics Data System (ADS)

    Todosi, Cristian; Niculita, Mihai

    2016-04-01

    Sediment budgets are a useful tool for geomorphologic analysis, catchment management and environmental assessment, despite the uncertainties related to their assessment. We present the sediment budget construction and validation for a small catchment of 9.5319 kmp (953.19 ha) situated in the North-Eastern part of Romania. The Rediu reservoir was built between 1986 and 1988, on Rediu valley, a left tributary of Bahlui river, north-west from Iasi city. The catchment of the reservoir has 6.5 km in length and 2.5 km in maximum width, the altitudes decreasing from 170 m in the northern part, to 52 m in the southern part. The valley is symmetric, the altitude of the hillslopes going between 200 m to 75 m in one km length, in the transversal section with the maximum width. The floodplain is narrow having between 20 m to 210 m (in the area of confluence with Breazu tributary). The mean slope of the catchment is 6.4 degree, the maximum slope being 24.6 degrees. The length of channels which show banks of up to 2 m is 19.98 km. The land is used predominantly as crops (58.1 %), 16.7 % being covered by pastures (from which over half are eroded), 11.5 % percent of the catchment being covered by planted forests, 9.2 % by rural constructions and roads, 2.9 % by hayfields, 1.5 % by lakes and 0.1 % by orchards. Beside the Rediu reservoir, there are three ponds (15 771, 1761 and 751 sqm) in the catchment. We considered the trap efficiency for the reservoir and the ponds to be 95%. Aerial images from 1963, 1978 , 1984, 2005, 2008, 2010, 2012 and 2014 were used to assess the state of geomorphological processes before and after the reservoir construction. After 1970 a gully system situated in Breazu tributary sub-catchment and several active landslides along the main valley left side were forested. Beside these processes, soil erosion and human impact by constructions are the main processes generating sediment in the study area. The sediment yields were quantified by estimating the

  4. Characterising groundwater-dominated lowland catchments: the UK Lowland Catchment Research Programme (LOCAR)

    NASA Astrophysics Data System (ADS)

    Wheater, H. S.; Peach, D.; Binley, A.

    2007-01-01

    This paper reports on a major UK initiative to address deficiencies in understanding the hydro-ecological response of groundwater-dominated lowland catchments. The scope and objectives of this national programme are introduced and focus on one of three sets of research basins - the Pang/Lambourn Chalk catchments, tributaries of the river Thames in southern England. The motivation for the research is the need to support integrated management of river systems that have high ecological value and are subject to pressures that include groundwater abstraction for water supply, diffuse pollution, and land use and climate change. An overview of the research programme is provided together with highlights of some current research findings concerning the hydrological functioning of these catchments. Despite the importance of the Chalk as a major UK aquifer, knowledge of the subsurface movement of water and solutes is poor. Solute transport in the dual porosity unsaturated zone depends on fracture/matrix interactions that are difficult to observe; current experimental and modelling research supports the predominance of matrix flow and suggests that slow migration of a time-history of decades of nutrient loading is occurring. Groundwater flows are complex; catchments vary seasonally and are ill-defined and karst features are locally important. Groundwater flow pathways are being investigated using natural and artificial geochemical tracers based on experimental borehole arrays; stream-aquifer interaction research is using a combination of geophysics, borehole array geochemistry and longitudinal profiles of stream flow and solutes. A complex picture of localised subsurface inflows, linked to geological controls and karst features, and significant longitudinal groundwater flow below the river channel is emerging. Management implications are discussed. Strategies to control surface application of nutrients are expected to have little effect on groundwater quality for several

  5. Participatory planning in river catchments, an innovative toolkit tested in Southern Africa and North West England.

    PubMed

    Tippett, J

    2005-01-01

    The European Union Water Framework Directive (WFD) offers an unparalleled opportunity for improving river basin management. Active participation is essential for its delivery. "End-of-pipe" solutions will not deliver the improvements needed to achieve its ambitious goals. This research tested DesignWays, a toolkit for participatory planning, as a mechanism for maximizing the long-term social and environmental benefits of such stakeholder and community participation. It examined the emerging role of "planning for sustainability" in the context of river catchments. Sustainable management of water requires integration, and recognition of interconnections between systems at different levels of scale. This is an endeavour in which systems thinking provides useful tools. The development of DesignWays was a conscious attempt to embed 'new paradigm' living systems metaphors into a practical planning tool. This paper begins with a description of DesignWays and its development in Southern Africa. An outline of the context of the action research in North-West England is followed by a description of the stages of the process, with highlights of the outcomes. This research had two major outcomes: a contribution to theory through an in-depth exploration of the theoretical basis of participatory, ecologically informed design; and a contribution to practice through investigating DesignWays' potential to meet key challenges of the WFD. This research points to the importance of understanding participatory planning as a societal process, aiming to make the process engaging and meaningful. It has pointed to the need to see participatory planning and education for sustainability as an integrated process. It demonstrated the benefits of an iterative process in which planning at the landscape level of scale informs, and is informed by, work at the site level. It has shown that an approach consistent with a living systems paradigm can contribute to the development of more integrated

  6. Seamless hydrological predictions for a monsoon driven catchment in North-East India

    NASA Astrophysics Data System (ADS)

    Köhn, Lisei; Bürger, Gerd; Bronstert, Axel

    2016-04-01

    Improving hydrological forecasting systems on different time scales is interesting and challenging with regards to humanitarian as well as scientific aspects. In meteorological research, short-, medium-, and long-term forecasts are now being merged to form a system of seamless weather and climate predictions. Coupling of these meteorological forecasts with a hydrological model leads to seamless predictions of streamflow, ranging from one day to a season. While there are big efforts made to analyse the uncertainties of probabilistic streamflow forecasts, knowledge of the single uncertainty contributions from meteorological and hydrological modeling is still limited. The overarching goal of this project is to gain knowledge in this subject by decomposing and quantifying the overall predictive uncertainty into its single factors for the entire seamless forecast horizon. Our study area is the Mahanadi River Basin in North-East India, which is prone to severe floods and droughts. Improved streamflow forecasts on different time scales would contribute to early flood warning as well as better water management operations in the agricultural sector. Because of strong inter-annual monsoon variations in this region, which are, unlike the mid-latitudes, partly predictable from long-term atmospheric-oceanic oscillations, the Mahanadi catchment represents an ideal study site. Regionalized precipitation forecasts are obtained by applying the method of expanded downscaling to the ensemble prediction systems of ECMWF and NCEP. The semi-distributed hydrological model HYPSO-RR, which was developed in the Eco-Hydrological Simulation Environment ECHSE, is set up for several sub-catchments of the Mahanadi River Basin. The model is calibrated automatically using the Dynamically Dimensioned Search algorithm, with a modified Nash-Sutcliff efficiency as objective function. Meteorological uncertainty is estimated from the existing ensemble simulations, while the hydrological uncertainty is

  7. Combining stable isotopes and hydrometric data to investigate the stormflow response of a Mediterranean mountain catchment (Vallcebre Research Catchments, Spain)

    NASA Astrophysics Data System (ADS)

    Latron, Jérôme; Roig-Planasdemunt, Maria; Llorens, Pilar; Gallart, Francesc

    2015-04-01

    The hydrological behaviour of Mediterranean mountain catchments has been investigated in the last two decades in the Vallcebre Research Catchments (NE Spain, 42° 12'N, 1° 49'E) using a twofold approach based on hydrometric measurements and modelling. Results obtained have shown the complexity of the rainfall-runoff relationship as well as the strong non-linearity of the catchment's hydrological response. The hydrological behaviour of the catchments is broadly similar to that observed in more humid regions during wet periods. On the contrary, during dry periods or during wetting up transitions, some runoff generation processes characteristic of humid conditions are temporarily absent, activating a different combination of hydrological processes. Water stable isotopes have been used in the last 3 years for determining the relative contribution of event and pre-event water in the stormflow response, with the aim of improving the understanding of the hydrological behaviour of these catchments. Even if the use of stable isotopes in seasonal Mediterranean catchments has been relatively limited so far compared to humid temperate catchments, results obtained in the Vallcebre Research Catchments showed that the information they provide was very helpful, when used in combination with detailed hydrometric data. Results obtained using stable isotopes were generally in line with previous finding in these catchments, even if the contribution of pre-event water was higher than expected in some conditions. Using a set of 10 stormflow events with different characteristics (antecedent conditions, rainfall depth and intensity, stormflow coefficient), two components hydrograph separations indicated that pre-event water accounted for 30% to almost 100% of the total runoff. The contribution of pre-event water depended more on rainfall characteristics than on antecedent wetness conditions. Moreover, a strong relationship was observed between the new water contribution and the suspended

  8. A decision support process to compare riparian revegetation options in Scheu Creek catchment in north Queensland.

    PubMed

    Qureshi, M E; Harrison, S R

    2001-05-01

    While riparin vegetation can play a major role in protecting land, water and natural habitat in catchments, there are high costs associated with tree planting and establishment and in diverting land from cropping. The distribution of costs and benefits of riparian revegetation creates conflicts in the objectives of various stakeholder groups. Multicriteria analysis provides an appropriate tool to evaluate alternative riparian revegetation options, and to accommodate the conflicting views of various stakeholder groups. This paper discusses an application of multicriteria analysis in an evaluation of riparian revegetation policy options for Scheu Creek, a small sub-catchment in the Johnstone River catchment in north Queensland, Australia. Clear differences are found in the rankings of revegetation options for different stakeholder groups with respect to environmental, social and economic impacts. Implementation of a revegetation option will involve considerable cost for landholders for the benefits of society. Queensland legislation does not provide a means to require farmers to implement riparian revegetation, hence the need for subsidies, tax incentives and moral suasion. PMID:11400460

  9. Decadal changes in the frequency of major floods in near-natural catchments across North America and Europe

    NASA Astrophysics Data System (ADS)

    Hodgkins, Glenn A.; Hannaford, Jamie; Whitfield, Paul H.; Burn, Donald H.; Fleig, Anne; Stahl, Kerstin; Renard, Benjamin; Korhonen, Johanna; Murphy, Conor; Crochet, Philippe; Wilson, Donna; Madsen, Henrik

    2013-04-01

    Recent major floods in North America and Europe have received much press, with some concluding that these floods are more frequent in recent years as a result of anthropogenic warming. There has therefore been considerable scientific effort invested in establishing whether observed flood records show evidence of trends or variability in flood frequency, and to determine whether these patterns can be linked to climatic changes. However, the river catchments used in many published studies are influenced by direct human alteration such as reservoir regulation and urbanisation, which can confound the interpretation of climate-driven variability. Furthermore, a majority of previous studies have analysed changes in low magnitude floods, such as the annual peak flow, at a national scale. Few studies are known that have analysed changes in large floods (greater than 25-year floods) on a continental scale. To fill this research gap, the current study is analysing flood flows from reference hydrologic networks (RHNs) or RHN-like gauges across a large study domain embracing North America and much of Europe. RHNs comprise gauging stations with minimally disturbed catchment conditions, which have a near-natural flow regime and provide good quality data; RHN analyses thus allow hydro-climatic variability to be distinguished from direct artificial disturbances or data inhomogeneities. One of the key innovations in this study is the definition of an RHN-like network on a continental scale. The network incorporates existing, well-established RHNs in Canada, the US, the UK, Ireland and Norway, alongside RHN-like catchments from Europe (France, Switzerland, Iceland, Denmark, Sweden, Finland), which have been incorporated in the network following a major effort to ensure RHN-like status of candidate gauges through consultation with local experts. As the aim of the study is to examine long-term variability in the number of major floods, annual exceedances of 25-, 50-, and 100-year

  10. Hydrologic responses of a tropical catchment in Thailand and two temperate/cold catchments in north America to global warming

    SciTech Connect

    Gan, T.Y.; Ahmad, Z.

    1997-12-31

    The hydrologic impact or sensitivities of three medium-sized catchments to global warming, one of tropical climate in Northern Thailand and two of temperate climate in the Sacramento and San Joaquin River basins of California, were investigated.

  11. Nutrient loss and water quality under extensive grazing in the upper Burdekin river catchment, North Queensland.

    PubMed

    O'Reagain, P J; Brodie, J; Fraser, G; Bushell, J J; Holloway, C H; Faithful, J W; Haynes, D

    2005-01-01

    of ground cover are maintained. In contrast, sediment and nutrient loss under grazing on more erodable land types is cause for serious concern. Long-term empirical research and monitoring will be essential to quantify the impacts of changed land management on water quality in the spatially and temporally variable Burdekin River catchment. PMID:15757706

  12. Linking the runoff response at micro-plot and catchment scale following wildfire and terracing, north-central Portugal

    NASA Astrophysics Data System (ADS)

    Martins, Martinho A. S.; Rial-Rivas, María E.; Machado, Ana I.; Serpa, Dalila; Prats, Sergio A.; Faria, Sílvia R.; Varela, María E. T.; González-Pelayo, Óscar; Keizer, J. Jacob

    2015-04-01

    Wildfires are known as one of the principal natural hazards affecting the Mediterranean region. This includes Portugal, where wildfires have affected some 100.000 ha of rural lands each year. The effects of wildfires on runoff generation and/or the associated soil (fertility) losses have been studied in Portugal for more than two decades. Some of these studies have reported strong and sometimes extreme hydrological responses in recently burnt areas. Forestry operations in such areas have increasingly come to include bench terracing in preparation of new eucalypt plantations. The hydrological impacts of bench terracing, however, have received little research attention so far and the few existing publications are limited to small spatial scales. The construction of terraces is commonly considered an effective practice for soil conservation on steep slopes, having been applied by mankind since early history. Nonetheless, the present authors have measured high rates of splash as well as inter-rill erosion on recently constructed terraces, and have regularly observed rill formation, including on forest tracks which typically constitute an extensive network in such bench terraced plantations. The present study was carried out in a 29-ha forest catchment in north-central Portugal that was burnt by a wildfire during the summer of 2010, logged during early winter 2010/11, and then bench terraced with bulldozers during late winter 2011, some 6 months after the wildfire. The catchment outlet was instrumented immediately after the fire with an automatic hydrometric station comprising two subsequent flumes with maximum discharge capacities of 120 and 1700 l sec-1. Within the catchment, rainfall was measured using several automatic and storage gauges and overland flow was monitored on two contrasting slopes using 3 micro-plots of approximately 0.25m2 on each slope.Overland flow was measured at 1- to 2-weekly intervals during the hydrological years of 2010/11 and 2011/12, i

  13. Assessing the Age of Particulate Organic Matter Exported from a Temperate Rainforest Catchment of the North American Pacific Coast

    NASA Astrophysics Data System (ADS)

    Martin, E. E.; Ingalls, A. E.; Santos, G.; Keil, R. G.; Wefferling, L.; Jones, A.; Druffel, E. R. M.

    2015-12-01

    Although temperate rainforests of the North American Pacific Coast contain a small proportion of the world's forests, they contain some of the highest densities of biomass of any terrestrial system, and they store large quantities of carbon in soil. Understanding the residence time of organic carbon in these watersheds is of ecological significance. Given that rivers can mobilize sediment (and associated carbon) from across the catchment, carefully deciphering the organic signatures found within riverine particles can be a powerful tool to inform our understanding of carbon cycling catchment-wide. Here we examine the lignin phenol content (lignin is a biomarker unique to vascular plants) and the radiocarbon age (Δ14C) of fine particulate organic carbon (FPOC) exported by the Queets River of Washington State's Olympic Peninsula over the course of one year, targeting winter storm events. This mountainous catchment is one of the largest and most pristine found on the Olympic Peninsula. The Δ14C of FPOC was quantified for each of the twelve sampling events, whereas the Δ14C of the individual lignin phenols was determined during a late-winter storm event. Sediments were enriched in lignin phenols at the end of the summer dry season and into the first storm of the fall, suggesting that surface soils were transported early on. The Δ14C of individual lignin phenols ranged from -161 to 26‰, with biomarkers for non-woody vegetation being most depleted. These results suggest that particulate lignin exported from temperate catchments is considerably aged, especially relative to the tropics. These findings are consistent with cool temperatures and abundant moisture limiting microbial decomposition, increasing the residence time of plant-derived organic carbon in temperate rainforests. We will compare the Δ14C content of lignin phenols to that of bulk organic matter to partition riverine FPOC amongst possible organic matter sources.

  14. Overview of North American stored product research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Major locations for stored product research in North America are in Winnipeg, Manitoba, Canada, and Manhattan, Kansas, USA. Recent personnel changes and research areas are reviewed. One of the pressing research areas in the U.S. is reducing the need for fumigations in flour mills and evaluating alte...

  15. Historical changes in the annual number of large floods in near-natural catchments across North America and Europe, 1931-2010

    NASA Astrophysics Data System (ADS)

    Hodgkins, Glenn; Whitfield, Paul; Hannaford, Jamie; Burn, Donald; Renard, Benjamin; Stahl, Kerstin; Fleig, Anne; Madsen, Henrik; Mediero, Luis; Korhonen, Johanna; Murphy, Conor; Crochet, Philippe; Wilson, Donna

    2014-05-01

    Previous investigations have analyzed historical changes in low magnitude floods, such as the annual peak flow, at regional or national scales. These investigations often use catchments where streamflows have been influenced by human alterations such as reservoir regulation or urbanization. No known studies have analyzed changes in large floods (greater than 25-year return period floods) at a continental scale for near-natural catchments. To fill this research gap, this study analyzed flood flows from reference hydrologic networks (RHNs) or RHN-like gauges in North America (United States and Canada) and Europe (United Kingdom, Ireland, France, Spain, Germany, Switzerland, Iceland, Norway, Denmark, Sweden, and Finland). RHNs are formally defined networks in several countries that comprise gauges with a natural or near-natural flow regime and that provide good quality data. Selected RHN-like gauges were included following a major effort to ensure RHN-like status through consultation with local experts. Some 1206 study gauges met near-natural and completeness criteria for 1961-2010 and 322 gauges met criteria for 1931-2010. Peak flows with recurrence intervals of 25, 50, and 100 years were estimated using the generalized extreme-value distribution and L-moments, and peak flows at each gauge that exceeded these flood thresholds in each year were compiled. Continental and regional trends over time in the annual number of large floods, including groups differentiated by catchment size and major Köppen-Geiger climate group, are being computed and will be presented at EGU. Plots will also show the decadal variability in the annual number of large floods. The unique dataset used for this study is an example of successful international collaboration on hydro-climatic data exchange, which is potentially a step towards establishing RHN or RHN-like networks and analyzing near-natural streamflows on a global scale.

  16. Predicting nutrient responses to mitigation at catchment to national scale: the UK research platform (Invited)

    NASA Astrophysics Data System (ADS)

    Johnes, P.

    2013-12-01

    Nutrient enrichment of waters from land-based and atmospheric sources presents a significant management challenge, requiring effective stakeholder engagement and policy development, properly underpinned by robust scientific evidence. The challenge is complex, raising significant questions about the specific sources, apportionment and pathways that determine nutrient enrichment and the key priorities for effective management and policy intervention. This paper presents outputs from 4 major UK research programmes: the Defra Demonstration Test Catchments programme (DTC), the Environment Agency's Catchment Sensitive Farming monitoring and evaluation programme (CSF), Natural Resources Wales Welsh Catchment Initiative (WCI) and the NERC Environmental Virtual Observatory programme (EVOp). Funded to meet this challenge, they are delivering new understanding of the rates and sources of pollutant fluxes from land to water, their impacts on ecosystem goods and services, and likely trends under future climate and land use change from field to national scale. DTC, a 12m investment by the UK Government, has set up long-term, high resolution research platforms equipped with novel telemetered sensor networks to monitor stream ecosystem responses to on-farm mitigation measures at a representative scale for catchment management. Ecosystem structural and functional responses and bulk hydrochemistry are also being monitored using standard protocols. CSF has set up long-term, enhanced monitoring in 8 priority catchments, with monthly monitoring in a further 72 English catchments and 6 Welsh priority catchments, to identify shifts in pollutant flux to waters resulting from mitigation measures in priority areas and farming sectors. CSF and WCI have contributed to >50 million of targeted farm improvements to date, representing a significant shift in farming practice. Each programme has generated detailed evidence on stream ecosystem responses to targeted mitigation. However, to provide

  17. Mechanisms to improve integrative research at the science-policy interface for sustainable catchment manageme

    NASA Astrophysics Data System (ADS)

    MacLeod, C. J. A.; Blackstock, K. L.; Haygarth, P. M.

    2009-04-01

    There is a need for greater levels of integration between researchers and policy makers to provide an evidence base that is transparent, integrated, and adaptive to support the complexities of sustainable catchment management. Opening up and closing down mechanisms are equally important in creating and establishing such an evidence base. We provide examples of both types based on our recent research and knowledge transfer activities at the science-policy interface. Through our coordination role for the UK government we provide opening up forums for researchers and government science and policy staff to learn about and assess the gaps and uncertainties of the evidence base. Closing down mechanisms are also vital to policy making on sustainable catchment management, in that they distil what is known and what is unknown. The diffuse pollution user manual provides a valuable tool for policy and catchment management staff to assess the potential effectiveness of different combinations of remedial diffuse pollution mitigation methods. We argue that it is important that opening up and closing down mechanisms are iteratively linked given the complexity and uncertainty of the science and policy cycles. Advances in integrative research at the science-policy interface are vital if there is to be a move to more deliberative policy making.

  18. Response of sap flow to environmental factors in the headwater catchment of Miyun Reservoir in subhumid North China

    NASA Astrophysics Data System (ADS)

    Tie, Qiang; Hu, Hongchang; Tian, Fuqiang; Liu, Yaping; Xu, Ran

    2015-04-01

    Since the headwater catchment of Miyun Reservoir is the main drinking water conservation area of Beijing, its water cycle is of importance for the regional water resource. Transpiration is an important component of water cycle, which can be estimated by sap flow. In this study, the dynamics of sap flow and its response to environmental factors and relationship with leaf area index (LAI) were analyzed. The field study was conducted in the Xitaizi Experimental Catchment, located in the headwater catchment of Miyun Reservoir in subhumid North China. The Aspen (Populus davidiana) and Epinette (Larix gmelinii) are the two dominant tree species. Sap flow in 15 Aspen (Populus davidiana) trees was monitored using thermal dissipation probes (TDP) during the growing season of 2013 and 2014, and sap flow in another 3 Epinette (Larix gmelinii) trees was also monitored during September and October in 2014 for comparative analysis. Physiological and biometric parameters of the selected trees and the environmental factors, including meteorological variables, soil moisture content and groundwater table depth were measured. Vapor pressure deficit (VPD), variable of transpiration (VT) and reference crop evapotranspiration (ET0) were calculated using the measured environmental factors. The LAI, which is used to characterize phenophase, was calculated using the Moderate Resolution Imaging Spectroradiometer (MODIS) LAI product (MCD15A3). Correlation analysis for daily sap flow and air temperature, relative humidity, precipitation, wind speed, solar radiation, VPD, VT and ET0 under different soil moisture and groundwater table depth conditions was performed. Diurnal course and hysteresis of sap flow were analyzed as a function of air temperature, solar radiation, VPD and VT on the typical sunny, cloudy and rainy days under different soil moisture conditions. Correlation analysis between daily sap flow and LAI showed that LAI and phenophase significantly influence sap flow and restrict

  19. Testing fine sediment connectivity hypotheses using fallout radionuclide tracers in a small catchment with badlands. Vallcebre Research Catchments (NE Spain)

    NASA Astrophysics Data System (ADS)

    Gallart, Francesc; Latron, Jérôme; Vuolo, Diego; Martínez-Carreras, Núria; Pérez-Gallego, Nuria; Ferrer, Laura; Estrany, Joan

    2016-04-01

    In the Vallcebre Research Catchments (NE Spain), results obtained during over 20 years showed that badlands are the primary sources of sediments to the drainage network. Parent lutitic rocks are weathered during winter producing regoliths, which are eroded from badland surfaces mainly during summer intense rainstorms. Even if the produced sediments are mainly fine, due to the ephemeral nature of summer runoff events most of them are deposited on the stream beds, where they may remain during some time (months to years). Within the MEDhyCON project, a fallout radionuclides (FRNs) tracing experiment (i.e., excess lead 210 (Pbx-210) and beryllium 7 (Be-7)) is being carried out in order to investigate sediment connectivity. A simplified Pbx-210 balance model on badland surfaces suggested a seasonal sawtooth-like activity pattern: FRN being accumulated in regoliths from October to June and depleted in summer. Early summer erosion events would produce the sediments with the highest activity whereas late summer events would produce sediments with the lowest activity coming from the deeper regolith horizons. These findings lead us to launch two sediment transfer connectivity hypotheses analysing respectively the temporal and spatial variability of the Pb-210 activities within the fine sediments at the small catchment scale: (1) The temporal variability of suspended sediment activities at the gauging stations is a measure of sediment transfer immediacy, ergo connectivity. Hence, a high variability in suspended sediment activities, mimicking regolith activity temporal pattern would indicate high connectivity, whereas a low variability, meaning that sediments are mostly pooled in a large and slowly moving stock, would indicate low connectivity. (2) In a drainage system where fine sediments temporarily remain on the dry stream bed, the ratio between fine sediment activities at the sources and fine in-stream sediment activities downstream is a measure of sediment connectivity

  20. Spatio-temporal variability of shallow groundwater during rainfall-runoff events in a Mediterranean mountain catchment (Vallcebre Research Catchments, Spain)

    NASA Astrophysics Data System (ADS)

    Roig-Planasdemunt, Maria; Llorens, Pilar; Latron, Jérôme

    2016-04-01

    With the aim of improving the knowledge of the hydrological functioning of Mediterranean mountain areas, this work investigates the spatial and temporal dynamics of the depth to water table during rainfall-runoff events in the Vallcebre Research Catchments (NE Spain, 42° 12'N, 1° 49'E). In combination with rainfall and runoff measurements, the depth to the water table was monitored at 13 locations within the Can Vila catchment (0.56 km2) during 19 rainfall-runoff events. The distribution of piezometers in the catchment allows examining the effect of topography and distance from the stream on the spatial and temporal distribution of depth to water table. On the other hand, the analysis of different rainfall-runoff events allows investigating the role of antecedent wetness conditions on the shallow groundwater dynamics associated to the streamflow response. Results show that the depth to water table did not rise in unison throughout the catchment during rainfall-runoff events. The shallow groundwater response was clearly different between locations near and far from the stream. However, this response was not clearly related to the topography. The antecedent wetness conditions were found as the most important control on the spatio-temporal variability of the groundwater response, which in turn affects the magnitude of the streamflow response. In dry conditions, a higher spatio-temporal variability of depth to water table as well as a much slower response of the groundwater was observed.

  1. The artificial catchment `Chicken Creek' (`Huehnerwasser') as a new research tool for hydrological and ecological studies

    NASA Astrophysics Data System (ADS)

    Gerwin, W.; Schaaf, W.; Hüttl, R. F.

    2009-04-01

    The most important framework of many ecological studies are watersheds as landscape units for water and element budgets. However, internal structures of natural catchments are often not well known due to natural heterogeneity and difficult boundary conditions. Important information has to be extrapolated from point measurements or indirect exploration methods. In contrast, artificial watersheds have the advantage of better defined boundaries and internal structures. Both local boundary conditions, e.g. the accordance of the surface and the groundwater catchment or hydrologic parameters like drainage patterns, discharge points and stratification can be designed and precisely documented during site construction. A recently launched German-Swiss Collaborative Research Centre is investigating the 'Chicken Creek' watershed which can be seen as one of the largest artificially created catchments for scientific purposes worldwide. The main hypothesis of the Collaborative Research Centre is that initial structures define and shape the development of an ecosystem as well as its later stages. Against this background the artificial catchment was designed to offer manifold opportunities for hydrological oriented as well as ecological studies of an initial ecosystem. As internal structures are well known and the surface and subsurface boundaries are well defined compared to natural catchments the site offers high potentials for improving hydrological and ecological models. The catchment ‘Chicken Creek' in Lusatia (Germany; 150 km SE from Berlin) has an area of 6 ha. It was constructed as a 2-4 m layer of post-glacial sandy to loamy sediments overlying a 1-2 m layer of Tertiary clay that forms a shallow pan and seals the whole catchment at the base. No further measures of restoration like planting, amelioration or fertilization were carried out to allow natural succession and undisturbed development. At the bottom of the catchment a small lake with a diameter of 70 m and a

  2. Effects of land use on greenhouse gas fluxes and soil properties of wetland catchments in the Prairie Pothole Region of North America

    NASA Astrophysics Data System (ADS)

    Tangen, B.; Finocchiaro, R. G.; Gleason, R. A.

    2015-12-01

    Wetland restoration has been suggested as policy goal with multiple environmental benefits including enhancement of atmospheric carbon sequestration. However, there are concerns that increased CH4 emissions associated with restoration may outweigh the potential sequestration benefits. The Prairie Pothole Region (PPR) of North America is characterized by millions of depressional wetlands and spans climate and land-use gradients that have potential to affect biotic and abiotic factors associated with the overall greenhouse gas (GHG) balance of pothole wetland ecosystems. Thus, we conducted a comprehensive, 4-year study of 119 wetland catchments distributed throughout the U.S. portion of the PPR to assess the effects of land use and restoration practices on CH4 and N2O fluxes and soil properties.Results showed that the effects of land use on GHG fluxes and abiotic soil properties differed with respect to catchment zone (upland, wetland), wetland classification, geographic location, and year. CH4 fluxes were greater than previously reported for pothole wetlands, while N2O fluxes were comparable to previously reported values. Moreover, maximum cumulative CH4 fluxes were nearly 3 times as high as previously reported in North America.Results suggest that soil organic carbon is lost when relatively undisturbed catchments are converted for agriculture, but sequestration rates associated with restoration are variable. Further, when non-drained cropland catchments are restored, CH4 fluxes generally are not different than the pre-restoration baseline; conversely, when drained cropland catchments are restored, CH4 fluxes are noticeably higher. Consequently, it is important to consider the type of restoration when assessing restoration benefits. Results also suggest that elevated N2O fluxes from cropland catchments likely would be reduced through restoration. The overall variability discovered by this study underscores the difficulty in quantifying the GHG balance of wetlands.

  3. Hydrological connectivity for catchment management: research approaches, pathways and future agendas

    NASA Astrophysics Data System (ADS)

    Bracken, L. J.; Ali, G.; Roy, A. G.; Smith, M. W.; Tetzlaf, D.; Wainwright, J.

    2012-04-01

    The concept of hydrological connectivity is an overarching framework for understanding runoff and runon that has come to the fore in the last decade. Catchment management is a vital end-use of research around hydrological connectivity. The purpose of management is usually to maintain appropriate (dis)connectivity for different niches (hydrological, ecological, geomorphological), especially to be able to deal with what happens when structures are perturbed. Thus, for effective management and intervention in catchments a process-based understanding of connectivity is required so that: i) the conceptual rather than solely empirical understanding drives how managers interpret a system; and ii) there is an understanding of how continuous flow fields develop under different sets of environmental conditions to enable managers to know when, where and how to intervene successfully in catchment processes. Presently there is confusion around the structure: process dichotomy, shifting focus from understanding static indices influencing hydrological connectivity, to understanding the dynamics of process. Understanding different types and states of connections in catchments is helpful, but it is better to have an appreciation of processes to know that intervention is occurring in the most suitable way, or to prioritize limited resources. The aim of this presentation is to: i) evaluate the extent to which different concepts of hydrological connectivity have emerged from different approaches to measure and predict flow in different environments; ii) discuss the extent to which these different concepts are mutually compatible; and iii) explore what further research needs to be carried out to contribute to a unified understanding of hydrological processes. Approaches to investigating hydrological connectivity can be categorised as those: evaluating soil-moisture patterns (soil-moisture connectivity); understanding hillslope runoff patterns and processes (flow-process connectivity

  4. Measuring and monitoring snow deposition, properties and processes in mountain catchments of Western North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Patterns of snow deposition, and the distribution of snow properties and processes in mountainous regions of Western North America are highly heterogeneous. Wind and topographic structure control snow deposition, causing tremendous spatial heterogeneity in the distribution of the snowcover and the ...

  5. Ecohydrological separation in a Mediterranean mountain environment (Vallcebre research catchments, NE Spain)

    NASA Astrophysics Data System (ADS)

    Llorens, Pilar; Cayuela, Carles; Sánchez-Costa, Elisenda; Gallart, Francesc; Latron, Jérôme

    2016-04-01

    Until very recently, a general paradigm in hydrology was that water is well mixed in the soil, and therefore groundwater, stream water and plant transpiration are all sourced by this well mixed pool. However, recent works (Brooks et al., 2010; Goldsmith et al., 2012) have shown the existence of different water pools in the soil, where tightly bound water, potentially used by plants, does not mix with mobile water that potentially contributes to groundwater and streamflow. This new "two water worlds hypothesis" of ecohydrological separation of water between streams and trees should however be verified in areas with different climates and land covers (McDonnell, 2014). With this objective, we examine this hypothesis in the Vallcebre Research Catchments (NE Spain, 42° 12'N, 1° 49'E) using the dual isotope-based approach combined with meteorological and hydrometric monitoring. Since May 2015, stable water-isotopes have been monitored in rainfall (2 locations), in throughfall and stemflow below Scots pines as well as in stream water at the Can Vila (0.56 km2) catchment outlet. Moreover, three spatially distributed sampling campaigns in different antecedent soil moisture conditions have been performed (May, August and November 2015) within the catchment. During the sampling campaigns soil samples (10, 20, 30, 50 and 100 cm) and xylem samples (3 Scots pines) were collected at 8 locations, with different topographic indices. Water in soil and xylem samples was extracted by cryogenic vacuum distillation. This information was complemented with mobile soil water sampled in 3 lysimetric profiles (20, 50 and 100 cm) and in 13 piezometers (150-300 cm deep) distributed within the catchment. These campaigns were combined with a similar regular sampling, every 15 days (From May to December 2015) at one of the 8 locations. All the isotopic information, obtained by infrared spectroscopy, has been combined with continuous measurement of meteorological, soil moisture and potential

  6. Sediment connectivity in a small catchment with badlands: Testing connectivity indices using fallout radionuclide tracers at the Vallcebre Research Catchments.

    NASA Astrophysics Data System (ADS)

    Gallart, Francesc; Latron, Jérôme; Vuolo, Diego; Martínez-Carreras, Núria; Pérez-Gallego, Nuria; Estrany, Joan; Ferrer, Laura

    2015-04-01

    At the Vallcebre Research Catchments (South Eastern Pyrenees), results obtained during over 20 years showed that badlands are the primary sources of sediments to the drainage network. Parent lutitic rocks are weathered during winter producing regoliths, which are eroded from badland surfaces mainly during summer intense rainstorms. Even if the produced sediments are mainly fine, due to the ephemeral nature of summer runoff events most of them are deposited on the stream beds, where may remain during some time (months to years). Within the MEDhyCON project, a fallout radionuclides (FRNs) tracing experiment (i.e., excess lead 210 (Pbx-210) and beryllium 7 (Be-7)) is being carried out in order to investigate sediment connectivity. A simplified Pbx-210 balance model on badland surfaces suggested a seasonal sawtooth-like activity pattern: FRN would be accumulated in regoliths from October to June and depleted in summer. Early summer erosion events would produce the sediments with the highest activity whereas late summer events would produce sediments with the least activity coming from the deeper regolith horizons. These findings lead us to intend two sediment connectivity indices analysing respectively the temporal and spatial variability of the Pb-210 activities within the fine sediments: (1) The temporal variability of activities in suspended sediments at the gauging stations, being a measure of sediment transfer, ergo connectivity; a high variability mimicking regolith activity temporal pattern would represent high connectivity, whereas a low variability would involve that the sediments were pooled in a large and slowly moving stock. (2) The ratio between fine sediment activities at the sources and fine stream sediment activities downstream; fine stream sediment activities higher than those at their sources and increasing downstream (ratio lower than the unity) may indicate long-term permanence (low connectivity) of sediments in the stream beds, because once

  7. 12. View north of Tropic Chamber. Natick Research & ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. View north of Tropic Chamber. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  8. 2. View southwest of north facade elevation. Natick Research ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. View southwest of north facade elevation. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  9. Hydrochemical responses among nested catchments of the Sleepers River Research Watershed.

    NASA Astrophysics Data System (ADS)

    Sebestyen, S. D.; Boyer, E. W.; Shanley, J. B.; Kendall, C.

    2005-12-01

    We are probing chemical and isotopic tracers of dissolved organic carbon (DOC) and nitrate over both space and time to determine how stream nutrient dynamics change with increasing basin size and differ with flow conditions. At the Sleepers River Research Watershed in northeastern Vermont, USA, 20 to 30 nested sub-basins that ranged in size from 3 to 11,000 ha were sampled repeatedly under baseflow conditions. These synoptic surveys showed a pattern of heterogeneity in headwaters that converged to a consistent response at larger basin sizes and is consistent with findings of other studies. In addition to characterizing spatial patterns under baseflow, we sampled rainfall and snowmelt events over a gradient of basin sizes to investigate scaling responses under different flow conditions. During high flow events, DOC and nitrate flushing responses varied among different basins where high-frequency event samples were collected. While the DOC and nitrate concentration patterns were similar at four headwater basins, the concentration responses of larger basins were markedly different in that the concentration patterns, flushing duration, and maximum concentrations were attenuated from headwaters to the largest basin. We are using these data to explore how flow paths and solute mixing aggregate. Overall, these results highlight the complexities of understanding spatial scaling issues in catchments and underscore the need to consider event responses of hydrology and chemistry among catchments.

  10. Residents' perceptions of water quality improvements following remediation work in the Pymme's Brook catchment, north London, UK.

    PubMed

    Faulkner, H; Green, A; Pellaumail, K; Weaver, T

    2001-07-01

    Residents' perceptions of water quality change following remediation work in the upper Pymme's Brook catchment (north London) were elicited by questionnaire and compared with monitored changes in Escherichia coli count and BMWP (The Biological Monitoring Working Party (BMWP)) score. The wider usefulness of consumer perception surveys was then discussed. Monthly data collected between 1990 and 1996 shows that both E. coli count and BMWP score improved following flushing of the foul sewerage system in 1992, but that only E. coli count improved following the subsequent completion of large-scale remedial engineering works. Local residents were surveyed regarding their awareness of the scheme, and the causes of pollution, together with their perceptions as to the effects of the engineering works and of the resulting water quality improvements. Most respondents selected and ranked indicators in a way that suggested they had an awareness of the significance of various indicators of pollution severity. Following completion of the remediation scheme, residents perceived the watercourse to contain less rubbish and sewage fungus, and to have an improved colour and smell, which corresponds favourably to the monitored improvements. However, respondents' perceptions were found to vary when the study population was sub-divided using a range of parameters. For instance, frequent observers of the brook were most likely to correctly identify sewage as the main form of pollution. These divergent perceptions suggest that there may be considerable difficulties when perception surveys are used to quantify 'benefits' following environmental improvement programmes. Nevertheless, the survey was clearly beneficial in enhancing residents' awareness of their environment and the role of their voice in its management. PMID:11475083

  11. The Skogaryd Research Catchment - an infrastructure to integrate terrestrial and aquatic greenhouse gas fluxes

    NASA Astrophysics Data System (ADS)

    Klemedtsson, Leif; Weslien, Per; Bastviken, David; Natchimuthu, Sivakiruthika; Wallin, Marcus

    2015-04-01

    The Skogaryd Research Catchment (SRC; 58°23'N, 12°09'E, hemiboreal) is part of the Swedish Infrastructure for Ecosystem Science (SITES, www.fieldsites.se). SITES is a national coordinated infrastructure for terrestrial and limnological field research, consisting of nine research stations covering the different landscapes and climatic regions in Sweden. The SITES initiative is a long-term effort founded by the Swedish Research Council and the station owners. Researchers regardless of affiliation are welcome use the stations including the infrastructure in their research and perform experiments (after approval) or outsource tasks which are managed by the stations. Data collected in both background monitoring programs and previous and ongoing projects at the stations are also intended to support past, present and future research. Ecological, biogeochemical, and environmental research often focus on a specific ecosystem or have strict habitat boundaries. However, the growing awareness of systems interactions, feedbacks and large scale consequences calls for approaches that integrate across ecosystems and habitats to consider whole catchments, landscapes and regions. Thus there is an urgent need for long-term field sites that support integrative and cross-habitat-boundary research. Our aim at SRC is to develop methodologies to quantify GHG balances at the landscape scale in forested regions that include land-atmosphere, land-water, and water-atmosphere exchange of CO2, CH4 and N2O. Another aim is to promote investigations to elucidate the undelaying regulation of the biogeochemical processes. The SRC harbor several main habitats including mires, forests at different growth stages, lakes, and streams. The fluxes of greenhouse gases (GHG) are measured to a large extent according to ICOS protocol for the Eddy Covariance (EC) methodology for CO2, H2O, and CH4, as well as axillary data for habitats where such protocols exist. For aquatic habitats lacking such protocols

  12. An Open Source Framework for Coupled Hydro-Hydrogeo-Chemical Systems in Catchment Research

    NASA Astrophysics Data System (ADS)

    Delfs, J.; Sachse, A.; Gayler, S.; Grathwohl, P.; He, W.; Jang, E.; Kalbacher, T.; Klein, C.; Kolditz, O.; Maier, U.; Priesack, E.; Rink, K.; Selle, B.; Shao, H.; Singh, A. K.; Streck, T.; Sun, Y.; Wang, W.; Walther, M.

    2013-12-01

    This poster presents an open-source framework designed to assist water scientists in the study of catchment hydraulic functions with associated chemical processes, e.g. contaminant degradation, plant nutrient turnover. The model successfully calculates the feedbacks between surface water, subsurface water and air in standard benchmarks. In specific model applications to heterogeneous catchments, subsurface water is driven by density variations and runs through double porous media. Software codes of water science are tightly coupled by iteration, namely the Storm Water Management Model (SWMM) for urban runoff, Expert-N for simulating water fluxes and nutrient turnover in agricultural and forested soils, and OpenGeoSys (OGS) for groundwater. The coupled model calculates flow of hydrostatic shallow water over the land surface with finite volume and difference methods. The flow equations for water in the porous subsurface are discretized in space with finite elements. Chemical components are transferred through 1D, 2D or 3D watershed representations with advection-dispersion solvers or, as an alternative, random walk particle tracking. A transport solver can be in sequence with a chemical solver, e.g. PHREEQ-C, BRNS, additionally. Besides coupled partial differential equations, the concept of hydrological response units is employed in simulations at regional scale with scarce data availability. In this case, a conceptual hydrological model, specifically the Jena Adaptable Modeling System (JAMS), passes groundwater recharge through a software interface into OGS, which solves the partial differential equations of groundwater flow. Most components of the modeling framework are open source and can be modified for individual purposes. Applications range from temperate climate regions in Germany (Ammer catchment and Hessian Ried) to arid regions in the Middle East (Oman and Dead See). Some of the presented examples originate from intensively monitored research sites of the

  13. Presence-only approach to assess landslide triggering-thickness susceptibility. A test for the Mili catchment (North-Eastern Sicily, Italy)

    NASA Astrophysics Data System (ADS)

    Lombardo, Luigi; Fubelli, Giandomenico; Amato, Gabriele; Bonasera, Mauro; Hochschild, Volker; Rotigliano, Edoardo

    2015-04-01

    This study aims at comparing the performances of a presence only approach, namely Maximum Entropy, in assessing landslide triggering-thickness susceptibility within the Mili catchment, located in the north-eastern Sicily, Italy. This catchment has been recently exposed to three main meteorological extreme events, resulting in the activation of multiple fast landslides, which occurred on the 1st October 2009, 10th March 2010 and 1st March 2011. Differently from the 2009 event, which only marginally hit the catchment, the 2010 and 2011 storms fully involved the area of the Mili catchment. Detailed field data was collected to associate the thickness of mobilised materials at the triggering zone to each mass movement within the catchment. This information has been used to model the landslide susceptibility for two classes of processes clustered into shallow failures for maximum depths of 0.5m and deep ones in case of values equal or greater than 0.5m. As the authors believed that the peculiar geomorphometry of this narrow and steep catchment played a fundamental role in generating two distinct patterns of landslide thicknesses during the initiation phase, a HRDEM was used to extract topographic attributes to express near-triggering geomorphological conditions. On the other hand, medium resolution vegetation indexes derived from ASTER scenes were used as explanatory variables pertaining to a wider spatial neighbourhood, whilst a revised geological map, the land use from CORINE and a tectonic map were used to convey an even wider area connected to the slope instability. The choice of a presence-only approach allowed to effectively discriminate between the two types of landslide thicknesses at the triggering zone, producing outstanding prediction skills associated with relatively low variances across a set of 20 randomly generated replicates. The validation phase produced indeed average AUC values of 0.91 with a standard deviation of 0.03 for both the modelled landslide

  14. Fluvial responses to volcanism: resedimentation of the 1800a Taupo ignimbrite eruption in the Rangitaiki River catchment, North Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Manville, Vern; Newton, Erin H.; White, James D. L.

    2005-02-01

    The potential for the generation of dangerous and damaging lahars and floods in response to the eruption of voluminous pyroclastic debris has become increasingly appreciated in recent years. The style and tempo of this response varies both between eruptions and between individual catchments impacted by a single eruption, so that an understanding of the factors controlling this variation is necessary for precise hazard assessment. The 1800a Taupo eruption from the Taupo Volcanic Centre in the central North Island of New Zealand devastated an area of 20,000 km 2 during eruption of a climactic ignimbrite, impacting the headwaters of all major rivers draining radially from this region. The Rangitaiki River, the subject of this paper, differs from other catchments in that the Taupo ignimbrite buried an essentially flat land surface inherited from a suite of welded ignimbrite sheets erupted between 320-340 and 230 ka. The middle reaches of the catchment are characterised by narrow, steep gorges alternating with low-gradient basins developed in tectonic half-grabens. Initially, remobilisation of pyroclastic material in the headwaters was dominated by hyperconcentrated sheet flows resulting in shallow reworking. In higher gradient areas, reintegration of drainage networks was achieved by incision of deep channels and gullies, assisted by breakouts from ephemeral lakelets developed in ignimbrite-dammed depressions. Braided, and later meandering, streams superseded this pattern as rill and gully systems stabilised and sediment yields fell leading to a decline in drainage density. Gorge reaches acted as efficient conduits for remobilised material while the basins acted as local depocentres for the temporary storage of volcaniclastic sediments, mediating the transfer of pyroclastic debris to the Bay of Plenty coast >100 km to the north. Reworking and resedimentation of pyroclastic debris began immediately after the eruption, peaking early and then rapidly declining so that

  15. ALASKA NORTH SLOPE OIL-FIELD RESTORATION RESEARCH STRATEGY (ANSORRS)

    EPA Science Inventory

    This document provides a research strategy to support ecological restoration of disturbances related to oil and gas developments on the North Slope of Alaska that is mutually beneficial to the arctic ecorestoration research community and the arctic regulatory community (including...

  16. Indirect emissions and isotopologue signatures of N2O from agricultural drainage water of a Pleistocene lowland catchment in North-Eastern Germany

    NASA Astrophysics Data System (ADS)

    Weymann, D.; Well, R.; Kahle, P.; Tiemeyer, B.; Flessa, H.

    2011-12-01

    Artificial drainage of low- and wetlands is a common practice in many agricultural regions to facilitate crop production. Agricultural drainage water was shown to be supersaturated with nitrous oxide (N2O), a major greenhouse gas thought to contribute to global warming and to the destruction of stratospheric ozone. Therefore, drainage of agricultural land has potential for indirect N2O emissions which are a highly uncertain component of the global N2O budget. This case study focuses on these emissions and further tries to unravel the source processes of N2O as well as the impact of its hydrological controls by applying an isotopologue approach. The research area was an intensively tile drained agricultural catchment embedded in the Pleistocene lowland of the federal state Mecklenburg-Vorpommern (North-Eastern Germany). Water sampling was conducted during the consecutive hydrological winter periods 2007/2008 and 2008/2009 by sampling a collector drain outlet and an adjacent drainage ditch. Besides concentrations of dissolved N2O and NO3- we determined the isotopologue signatures of N2O by measuring δ15Nbulk and δ18O as well as the 15N 'site preference', which characterizes the intramolecular distribution of the N isotopes within the asymmetric N2O molecule and is a promising tool to distinguish between the main source processes of N2O, nitrification and denitrification. The investigated hydrological winter periods varied considerably concerning the weather and hydrological conditions. During the comparatively wet winter period 2007/2008, indirect N2O emissions accounted for 0.17 kg N2O-N ha-1 a-1 and were thus higher than during the colder and comparatively dry 2008/2009 period, where we found 0.12 kg N2O-N ha-1 a-1. The emission factors for both sampling periods were 0.23 % and 0.17 % of the N input, respectively, and therefore in good agreement with the current IPCC default value of 0.25 %. The isotopologue signatures of N2O reflected the different hydrological

  17. Teacher Salary Bonuses in North Carolina. Research Brief

    ERIC Educational Resources Information Center

    National Center on Performance Incentives, 2008

    2008-01-01

    In "Teacher Salary Bonuses in North Carolina"--a paper presented at the February 2008 National Center on Performance Incentives research to policy conference--Jacob Vigdor of Duke University reviews a teacher salary bonus program operating in North Carolina. Known officially as the ABC's of Public Education, the program awards teachers with…

  18. North American berry industries and research areas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The farm gate value of small fruit crops in North America has increased significantly in the last 10 years. Much of this increase is due to increased consumption for health benefits. Small fruits are rich in antioxidants which help prevent adverse effects of aging, cancer, and heart diseases. Acc...

  19. NORTH AMERICAN LANDSCAPE CHARACTERIZATION (NALC): RESEARCH PLAN

    EPA Science Inventory

    The North American Landscape Characterization (NALC) project is a component of the National Aeronautics and Space Administration (NASA) Landsat Pathfinder program of experiments to study global change issues. he NALC program is funded principally by the U.S. Environmental Protect...

  20. Estimation of diffuse and point source microbial pollution in the ribble catchment discharging to bathing waters in the north west of England.

    PubMed

    Wither, A; Greaves, J; Dunhill, I; Wyer, M; Stapleton, C; Kay, D; Humphrey, N; Watkins, J; Francis, C; McDonald, A; Crowther, J

    2005-01-01

    Achieving compliance with the mandatory standards of the 1976 Bathing Water Directive (76/160/EEC) is required at all U.K. identified bathing waters. In recent years, the Fylde coast has been an area of significant investments in 'point source' control, which have not proven, in isolation, to satisfactorily achieve compliance with the mandatory, let alone the guide, levels of water quality in the Directive. The potential impact of riverine sources of pollution was first confirmed after a study in 1997. The completion of sewerage system enhancements offered the potential for the study of faecal indicator delivery from upstream sources comprising both point sources and diffuse agricultural sources. A research project to define these elements commenced in 2001. Initially, a desk study reported here, estimated the principal infrastructure contributions within the Ribble catchment. A second phase of this investigation has involved acquisition of empirical water quality and hydrological data from the catchment during the 2002 bathing season. These data have been used further to calibrate the 'budgets' and 'delivery' modelling and these data are still being analysed. This paper reports the initial desk study approach to faecal indicator budget estimation using available data from the sewerage infrastructure and catchment sources of faecal indicators. PMID:15850190

  1. A cross-site comparison of factors controlling streamwater carbon flux in western North American catchments (Invited)

    NASA Astrophysics Data System (ADS)

    Brooks, P. D.; Biederman, J. A.; Condon, K.; Chorover, J.; McIntosh, J. C.; Meixner, T.; Perdrial, J. N.

    2013-12-01

    Increasing variability in climate is expected to alter the amount and form of terrestrial carbon in stream water both directly, through changes in the magnitude and timing of discharge, and indirectly through changes in land cover following disturbance (e.g. drought, fire, or insect driven mortality). Predicting how these changes will impact individual stream-catchment ecosystems however, is hampered by a lack of concurrent observations on both dissolved and particulate carbon flux across a range of spatial, temporal, and discharge scales. Because carbon is strongly coupled to most biogeochemical reactions within both aquatic and terrestrial ecosystems, this represents a critical unknown in predicting the response of catchment-ecosystems to concurrent changes in climate and land cover. This presentation will address this issue using a meta-analysis of dissolved organic, dissolved inorganic, and particulate organic carbon fluxes from multiple locations, including undisturbed sites along a climate gradient from desert rivers to seasonally snow-covered, forested mountain catchments, and sites disturbed by both fire and extensive, insect driven mortality. Initial analyses suggest that dissolved (organic and inorganic) and particulate fluxes respond differently to various types of disturbance and depend on interactions between changes in size of mobile carbon pools and changes in hydrologic routing of carbon to streamwater. Anomalously large fluxes of both dissolved and particulate organic matter are associated with episodic changes in hydrologic routing (e.g. storm floods; snowmelt) that connect normally hydrologically isolated carbon pools (e.g. surficial hillslope soils) with surface water. These events are often of short duration as the supply of mobile carbon is exhausted in short term flushing response. In contrast, disturbances that increase the size of the mobile carbon pool (e.g. widespread vegetation mortality) result smaller proportional increases in

  2. The necessity of field research in prescription of Environmental Flows - A case of the hydropower dominated Middle Zambezi Catchment

    NASA Astrophysics Data System (ADS)

    Mwelwa, Elenestina; Crosato, Alessandra; Wright, Nigel; Beevers, Lindsay

    2013-04-01

    The research work in the Middle Zambezi sub-catchment has the key objective to investigate the state of the river and its flood plain in terms of flow variation, river and flood plain morphological variation for both the pre and post hydropower schemes. From the rich biodiversity that this area supports, both Zambia and Zimbabwe has established National Parks with Mana Pools National Park, Sapi and Chewore safari areas being designated as UNESCO World Heritage Site in 1984. The habitat sustenance depend on the river channels and the associated morphological features with the flood and recession interaction whose modification can lead to negative environmental consequences. The research findings on the state of the sub-catchment flows and morphology will be outlined. Highlights will be given on the following findings: dominance of hydropower regulation in the water balance of the river reach, historical map analysis and related rates of river channel morphology changes associated to dam operating events and, bed load sediment characterisation and distribution. With the use of SOBEK-Rural (1D/2D) model, analysis of future state of the sub-catchment will be outlined, taking into account the following scenarios: no dam state of the river reach; continue with current water regulation and operations; modification in water regulation to take into account favorable changes and; climate related variation of droughts. The research deductions and implications for maintaining the current dam operation practices will be outline as relates to the sustainability of the hydro-morphology and ecosystem of the catchment which support a rich wildlife habitat. The research observed critical water needs form the basis for environmental flows prescription and recommendation. Whereas the restoration of regular flooding has been identified to be important, the most critical need however is the timing of flood gate regulation which has been observed as a trigger to loss of islands and bars

  3. Hydrological and erosion response at micro-plot to -catchment scale following forest wildfire, north-central Portugal

    NASA Astrophysics Data System (ADS)

    Vieira, Diana; Keizer, Jan Jacob; Nunes, João. Pedro; Fernandes, Isabel; Ferreira, Raquel; Pereira, Luísa; Prats, Sergio; Ermitas Rial, María.; Eufemia Varela, María.

    2010-05-01

    Wildfires can have important impacts on hydrological and soil erosion processes, due to the destruction of vegetation cover and changes to soil properties. According to Shakesby and Doerr (2006), these wildfire effects are: i) much better known at small spatial scales (especially erosion plots) than at the scale of catchments; ii) much better studied with respect to overland flow and streamflow (and, then, especially peak discharges) than to soil erosion. Following up on a precursor project studying runoff generation and the associated soil losses from micro-plot to slope-scale in Portuguese eucalypt forests, the EROSFIRE-II project addresses the connectivity of these processes across hillslopes as well as within the channel network. This is done in the Colmeal study area in central Portugal, where the outlet of an entirely burnt catchment of roughly 10 ha was instrumented with a gauging station continuously recording water level and tubidity, and five slopes were each equipped with 4 runoff plots of < 0,5 m2 ("micro-plot") and 4 slope-scale plots as well as 1 slope-scale sediment fence. Starting one month after the August 2008 wildfire, the plots were monitored at 1- to 2-weekly intervals, depending on the occurrence of rainfall. The gauging station became operational at the end of November 2008, since the in-situ construction of an H-flume required several weeks. A preliminary analysis of the data collected till the end of 2008, focusing on two slopes with contrasting slope lengths as well as the gauging station: revealed clear differences in runoff and erosion between: (i) the micro-plot and slope-scale plots on the same hillslope; (ii) the two slopes; (iii) an initial dry period and a subsequent much wetter period; (iv) the slopes and the catchment-scale, also depending on the sampling period. These results suggest that the different processes govern the hydrological and erosion response at different spatial scales as well as for different periods, with soil

  4. Hydrogeochemical modeling of alteration processes in the Ringelbach granitic research catchment (Vosges, France)

    NASA Astrophysics Data System (ADS)

    Schaffhauser, Thiebaud; Lucas, Yann; Fritz, Bertrand; Clément, Alain; Ambroise, Bruno; Stille, Peter; Chabaux, François

    2014-05-01

    The main goal of this work is to better constrain the parameters that control weathering processes at a small catchment scale, focusing specifically on the role of hydrology. For this purpose, temporal and spatial variations of the chemical water composition of the Ringelbach catchment (Vosges, France) are studied. Several springs of this catchment whose basement is composed of a more or less intensively fractured granite, outcropping along an altitudinal profile, were monthly sampled over a period of two years. The additional interest of this site is that three deep boreholes (down to a maximal depth of 150 meters) allow the sampling of both deep rocks and waters. The connectivity of the different hydrological compartments is evaluated based on the geochemical interpretation of water samples. A schematic hydrological functioning is proposed based on a good knowledge of the geological context. The originality of this study lays also in the combination of the geochemical and modeling approaches using the KIRMAT code (Kinetic Reactions and Mass transport) which integrates geochemical reactions (dissolution/precipitation) and 1D mass transport equations. It allows to simulate the reactive transport of a fluid through a rock along a given water pathway. This modeling is based on the characterization of the mineralogical and physical properties of the rock, sampled along the boreholes and leads to the geochemical interpretation of the water composition. Thus, the modeling of the chemical composition of the spring waters and borehole waters enables to improve the understanding of weathering processes including the role of precipitated secondary phases. It also allows to better understand the interplay of parameters that control the chemical signatures of the waters at the catchment scale.

  5. Olive Mounds, Roman cisterns, erosion pins - potential to characterize erosion in a Mediterranean catchment in north Jordan.

    NASA Astrophysics Data System (ADS)

    Kraushaar, Sabine; Ollesch, Gregor; Siebert, Christian; Vogel, Hans-Jörg

    2013-04-01

    In the framework of a three years' time period of a PhD thesis it is luck to catch the "right" rain events for good general erosion approximations. Methods that (i) cover longer time periods, (ii) are not confined to constructed boundaries, and finally (iii) include all possible erosion processes are crucial for good average estimates of sediment yields from different landscapes. The aim of the study was to get a first understanding of erosion processes and sediment yields in a Mediterranean to semi-arid catchment in NW Jordan, wherefore different measurement methods were tested in the predominant landscape units: olive orchards (27%), fields (14%) and natural shrubs on steep slopes (~30%). One of the applied methods was the measurement of topographic olive mounds within 7 orchards with an average size of 800 m2 in synergy with tree-coring and age estimation of the orchards. Furthermore the OSL dating of deposited sediments in two roman cisterns adjacent to fields was conducted and the 9 erosion pin fields, each about 200m2 large, were installed on steep slopes with natural vegetation. The methods cover different time scales from 560 years for the fields, an average of 32 years for the olive orchards and up to two rainy seasons for the erosion pin fields. Results show that olive orchards on steep slopes (>10%) have the highest erosion potential in the region with 95±8 t ha-1year-1 followed by natural vegetated slopes with 37±4 t ha-1year-1 of dislocated material and fields with 1.22±0.06 t ha-1year-1 sediment yield. These spatially constrained outcomes are supported by geochemical sediment fingerprint results of lake sediments from the catchment and will be discussed in regard to the basic assumption that underlie the principle of measurement and the limitations of the methods.

  6. The North: New Challenges for Creative Research.

    ERIC Educational Resources Information Center

    Grimsson, Olafur Ragnar

    2000-01-01

    A Northern research forum of scholars from universities in Arctic countries will study issues raised by the end of the Cold War, including new political institutions and relationships instituted in Northern regions, the relationship between environmental protection and sustainable economic growth, the relevance of traditional international…

  7. Black raspberry phytochemical research in North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our research group has focused on developing black raspberries with improved disease resistance and phytochemical traits over the last seven years. Recent interest in the rich color of black raspberries, and their historical use as an effective dye, derive from their anthocyanin composition and cont...

  8. The Krycklan Catchment Study—A flagship infrastructure for hydrology, biogeochemistry, and climate research in the boreal landscape

    NASA Astrophysics Data System (ADS)

    Laudon, Hjalmar; Taberman, Ida; Å; gren, Anneli; Futter, Martyn; Ottosson-Löfvenius, Mikaell; Bishop, Kevin

    2013-10-01

    The Krycklan Catchment Study (KCS) provides a unique field infrastructure for hillslope to landscape-scale research on short- and long-term ecosystem dynamics in boreal landscapes. The site is designed for process-based research assessing the role of external drivers including forest management, climate change, and long-range pollutant transport on forests, mires, soils, streams, lakes, and groundwater. The overarching objectives of KCS are to (1) provide a state-of-the-art infrastructure for experimental and hypothesis-driven research, (2) maintain a collection of high-quality, long-term climatic, biogeochemical, hydrological, and environmental data, and (3) support the development of models and guidelines for research, policy, and management.

  9. Bridging the Divide: understanding controls on nitrogen export by scaling from headwater catchments to eastern North America

    NASA Astrophysics Data System (ADS)

    Duncan, J. M.; Band, L. E.; Creed, I. F.; Duffy, C.; Green, M. B.; Groffman, P. M.; Tague, C.; Whittinghill, K. A.; Wollheim, W. M.

    2012-12-01

    A major challenge in ecohydrology is the development of a predictive understanding of the roles of land use and climate on nitrogen (N) cycling and export at regional to continental scales. A dramatic increase in anthropogenic N loads to terrestrial and aquatic ecosystems has contributed to forest decline, acidification of freshwater systems, and eutrophication of coastal and estuarine environments. Watershed studies have been a hallmark of ecosystem research and over the last few decades this approach has been refined to hierarchically link terrestrial and aquatic ecosystems as a continuum of water, carbon and nutrients along hydrologic flowpaths at multiple scales. We examine nested controls and feedbacks between biotic and abiotic processes controlling N cycling and export from watersheds within temperate forest biomes in eastern North America, a region that has undergone major changes in forest cover and structure as a result of historic logging, agricultural expansion then contraction, urbanization, N deposition, and climate change. Our conceptual model is that the controls on patterns of stream N concentrations and loads exported from watersheds emerge from a cascade of sources and sinks at multiple spatial and temporal scales that accumulate along converging flowpaths. This cascade integrates atmospheric, geologic, geomorphic, land use/land cover, water infrastructure and plant, soil and microbial responses. In order to synthesize controls at continental to patch (10-100 sq. m) scales, we must: (1) Understand how N is coupled to water and carbon cycling within reference forest ecosystems, broadly defined to including surface water drainage networks, across current climate, atmospheric N deposition, geologic, geomorphic and vegetation gradients; and (2) Develop a mechanistic understanding of how human activity alters the timing, magnitude and pattern of these coupled processes. Time series of N export patterns from long-term experimental watersheds across a

  10. Early North American research on lithium.

    PubMed

    Johnson, G; Gershon, S

    1999-12-01

    Research and clinical interest in lithium in the USA lagged behind that in Europe, largely because of the experience of deaths due to lithium in cardiac patients. The first American report on lithium was published in 1960 by Sam Gershon, the Australian psychiatrist who had undertaken lithium studies in Melbourne in conjunction with the physiologist Trautner. Major USA clinical trials originated in the 1960s; and the clinical significance of lithium was recognised in a special section in the American Journal of Psychiatry in 1968. The US Food and Drug Administration (FDA) approval of lithium for control of manic episodes was finally given in 1970. PMID:10622180

  11. Research of Houjiayao Unit in North China

    NASA Astrophysics Data System (ADS)

    Ji, Y.

    2012-12-01

    "Houjiayao Group" is the standard stratigraphic unit of late Pleistocene in northern China, which was created by Jia Lanpo and Wei Qi during their research on Houjiayao site. Based on the mammal, ancient human fossils and Paleolithic features, "Houjiayao Group" was thought as late Pleistocene sediments. "Houjiayao Group" was defined as late Pleistocene stratigraphic units. However, the problems of the age of "Houjiayao Group", stratigraphic division and other issues, have not yet been well resolved. These issues include: the differences of age-dating results, the unclear comparison between stratigraphic units and regional contrast, the uncertain relationship between "Houjiayao Group" and "Nihewan Layer ", and so on. Houjiayao site which located in the southeast of Houjiayao village in Dongjingji town Yangyuan County, Hebei province of China, is a very important paleolithic site. But some researches show that Houjiayao site is located at the 3th terrace of Liyigou valley and there are many opinions about the age of Houjiayao site, which varies from 20-500 thousand years. Combined with former research results and many research methods, our study was mainly focused on the key problems existing in the study of "Houjiayao Group". Through the use of sequence stratigraphy, chronostratigraphy, biostratigraphy and other theoretical methods, stratigraphic section was studied in the late Pleistocene stratigraphy and sedimentary environment. Through environmental indicators and the age-dating tests, the evolution of ancient geography and environment were identified elementarily. After analyzing informations of this area, geomorphologic investigation and stratum comparation in and around Houjiayao site were done. Houjiayao site is located on the west bank of Liyigou river, which has a tributary named Black Stone River. Two or three layers of volcanic materials were found in this area, those sediments are from a buried paleovolcano in upstream of Black Stone River. The volcanic

  12. Runoff generation processes in a small Mediterranean research catchment (Vallcebre, Eastern Pyrenees)

    NASA Astrophysics Data System (ADS)

    Latron, J.; Gallart, F.

    2008-09-01

    SummaryThis paper analyses the runoff generation processes in a small Mediterranean catchment (Can Vila catchment, 0.56 km 2), using limited continuous data on water table and soil water potential dynamics along with rainfall and runoff data collected over 6 years. At daily scale, strong non-linearity between rainfall and runoff volume and the effect of the water table position on how rainfall and runoff volume relate were seen. The higher the water table, the greater the runoff for a given rainfall. The relationship between runoff and depth of water table was not straightforward: water table variations sometimes did not correlate with runoff changes, suggesting somewhat intricate hydrological behaviour. Soil water potential data alongside runoff and water table data showed the relatively frequent development of a perched saturation layer in the profile monitored. Examination of soil water potential and water table dynamics during a collection of representative floods helped to identify three types of characteristic hydrological behaviour during the year. Hydrographs corresponding to type 1 events (dry conditions), type 2 events (wetting-up transition) and type 3 events (wet conditions) had different characteristics: each was associated with different dominant runoff generation processes. Under dry conditions, runoff was generated essentially as infiltration excess runoff in low permeable areas, whereas saturation excess runoff dominated during wetting-up and wet conditions. During wetting-up transition, saturated areas resulted from the development of scattered perched water tables, whereas in wet conditions they were linked to the rise of the shallow water table.

  13. A critical re-evaluation of controls on spatial and seasonal variations in nitrate concentrations in river waters throughout the River Derwent catchment in North Yorkshire, UK.

    PubMed

    Begum, Shaheen; Adnan, Muhammad; McClean, Colin J; Cresser, Malcolm S

    2016-05-01

    Since mean nitrate concentration along single river channels increases significantly with percent arable land use upstream of sampling points and autumn/early winter flushes in nitrate concentration are widespread, it is generally concluded that farmers contribute most of the nitrate. For the River Derwent in North Yorkshire, the correlation between nitrate concentration and percent arable land use is much poorer when tributary data are included in the equation, because of greater variations in dilution by water draining upland areas and in other N input sources. For the whole river system therefore, percent upland moorland/rough grazing land cover is an appreciably better predictor than percent arable land use for nitrate concentration. Upland land use encompasses the higher precipitation and runoff in such areas, and the subsequent greater dilution downstream of both arable land runoff and effluent from treatment works, as well as an inverse correlation to percent arable land use. This is strongly supported by the observation that, for the Derwent, Meteorological Office rainfall data alone proved even better than percent moorland rough grazing for predicting nitrate concentration. The dilution effect is therefore substantial but highly seasonal; lower runoff and dilution in summer offset the lower leaching losses from arable land, and higher dilution and runoff in winter offset greater nitrate leaching losses from arable soils. Because of this, coupled to improved efficiency of nitrogen fertilizer use, seasonality trends in nitrate concentrations that were pronounced a decade ago now have all but disappeared in the catchment. PMID:27102774

  14. Comparison of drought occurrence in selected Slovak and Czech catchments

    NASA Astrophysics Data System (ADS)

    Fendekova, Miriam; Fendek, Marian; Porubska, Diana; Hanel, Martin; Horacek, Stanislav; Martinkova, Marta; Vizina, Adam

    2014-05-01

    The presented study is focused on the analysis and comparison of hydrological drought occurrence, development and duration in six small to middle sized catchments in the Czech Republic (CZ) and Slovakia. The main questions to be answered are: (1) are there correlations between the physical conditions in the catchments and drought occurrence, and (2) does the spatial trend of drought occurrence exist. The Žitava catchment is located in the central western part of Slovakia having runoff dominated by rainfall with the contribution of snow melting during the spring period. The Belá River catchment is located on the contact of Západné and Vysoké Tatry Mts. in the north of Slovakia. The runoff is snow to snow-rain combined type. The Ľupčianka catchment is located on the northern slopes of the Nízke Tatry Mts. in the northern part of the central Slovakia. The runoff regime is snow-rain combined in the upper part of the catchment, and of rain-snow type in the rest of catchment. The Rakovnický potok brook (CZ) has its spring in Rakovnická pahorkatina hilly land. Runoff is dominated by rainfall, quite heavily influenced by water uptakes in the catchment. The Teplá River (CZ) originates in peat meadows in the western part of the Czech Republic. Runoff is dominated by rainfall. The Metuje catchment (CZ) is formed by Adršsbach-Teplické stěny Upland. The headwater part is typical by deeply incest valleys, table mountains and pseudokarst caves. The discharge is fed dominantly by groundwater. The streamflow drought was characterized using discharge data, the groundwater drought using the base flow values. The local minimum method was used for base flow separation. The threshold level method (Q80, BF80) and the sequent peak algorithm were used for calculation of drought duration in discharge and base flow time series. The data of the same three decades of the common period (1971 - 1980, 1981 - 1990 and 1991 - 2000) were used. The resulting base flow values along with

  15. MANAGEMENT POLICY FOR THE ASSURANCE OF RESEARCH QUALITY, HEALTH EFFECTS RESEARCH LABORATORY, RESEARCH TRIANGLE PARK, NORTH CAROLINA

    EPA Science Inventory

    The document presents policies, goals, and an organizational structure for the implementation of a management policy for the Quality Assurance program in the Health Effects Research Laboratory, Research Triangle Park, North Carolina. Directed toward functional managers, a system ...

  16. Cleanup of the Western Research Institute North Site. Final report

    SciTech Connect

    Merriam, N.W.

    1996-09-01

    The objective of this project is to clean up the Western Research Institute`s North Site in an environmentally sound and cost-effective manner. Work is broken down into the following phases: Phase 1, definition of waste streams; Phase 2, disposal of hazardous wastes; Phase 3, disposal of nonhazardous materials; Phase 4, soil sampling and disposal of buried wastes; Phase 5, decontamination and disposal of equipment; Phase 5a, groundwater monitoring; and Phase 6, preparation of material inventory database.

  17. A new approach to modeling the sediment retention service (InVEST 3.0): Case study of the Cape Fear catchment, North Carolina, USA.

    PubMed

    Hamel, Perrine; Chaplin-Kramer, Rebecca; Sim, Sarah; Mueller, Carina

    2015-08-15

    There is a growing call for ecosystem services models that are both simple and scientifically credible, in order to serve public and private sector decision-making processes. Sediment retention receives particular interest given the impact of this service on water quality. We developed a new version of the sediment retention model for the InVEST (Integrated Valuation of Environmental Services and Tradeoffs) tool to address previous limitations and facilitate model uncertainty assessment. We tested the model in the Cape Fear basin, North Carolina (NC), performing sensitivity analyses and assessing its ability to detect the spatial variability in sediment retention service for eight subcatchments. The main advantages of the revised model include the use of spatially-explicit, globally available input data, and the explicit consideration of hydrological connectivity in the landscape. The sensitivity analyses in the study catchment identified the erosivity and erodibility factors, together with the cover factor for agricultural land as the most influential parameter for sediment export. Relative predictions, representing the spatial variability in sediment exports, were correctly represented by the model. Absolute sediment exports were also highly correlated with observations, although their interpretation for socio-economic assessments is more uncertain without local knowledge of the dominant erosion processes. This work confirms that the sediment connectivity approach used in the revised InVEST model has great potential to quantify the sediment retention service. Although resources to conduct model calibration and testing are typically scarce, these practices should be encouraged to improve model interpretation and for confident application in different decision-making contexts. Without calibration, the InVEST sediment model still provides relevant information for ecosystem services assessments, especially in decision contexts that involve ranking of sediment export

  18. Effects of land use on greenhouse gas fluxes and soil properties of wetland catchments in the Prairie Pothole Region of North America

    USGS Publications Warehouse

    Tangen, Brian A.; Finocchiaro, Raymond G.; Gleason, Robert A.

    2015-01-01

    Results suggest that soil organic carbon is lost when relatively undisturbed catchments are converted for agriculture, and that when non-drained cropland catchments are restored, CH4 fluxes generally are not different than the pre-restoration baseline. Conversely, when drained cropland catchments are restored, CH4 fluxes are noticeably higher. Consequently, it is important to consider the type of wetland restoration (drained, non-drained) when assessing restoration benefits. Results also suggest that elevated N2O fluxes from cropland catchments likely would be reduced through restoration. The overall variability demonstrated by this study was consistent with findings of other wetland investigations and underscores the difficulty in quantifying the GHG balance of wetland systems.

  19. Environmental care in agricultural catchments: Toward the communicative catchment

    NASA Astrophysics Data System (ADS)

    Martin, Peter

    1991-11-01

    Substantial land degradation of agricultural catchments in Australia has resulted from the importation of European farming methods and the large-scale clearing of land. Rural communities are now being encouraged by government to take responsibility for environmental care. The importance of community involvement is supported by the view that environmental problems are a function of interactions between people and their environment. It is suggested that the commonly held view that community groups cannot care for their resources is due to inappropriate social institutions rather that any inherent disability in people. The communicative catchment is developed as a vision for environmental care into the future. This concept emerges from a critique of resource management through the catchment metaphors of the reduced, mechanical, and the complex, evolving catchment, which reflect the development of systemic and people-centered approaches to environmental care. The communicative catchment is one where both community and resource managers participate collaboratively in environmental care. A methodology based on action research and systemic thinking (systemic action research) is proposed as a way of moving towards the communicative catchment of the future. Action research is a way of taking action in organizations and communities that is participative and informed by theory, while systemic thinking takes into account the interconnections and relationships between social and natural worlds. The proposed vision, methodology, and practical operating principles stem from involvement in an action research project looking at extension strategies for the implementation of total catchment management in the Hunter Valley, New South Wales.

  20. Automotive Mg Research and Development in North America

    SciTech Connect

    Carpenter, Joseph A.; Jackman, Jennifer; Li, Naiyi; Osborne, Richard J.; Powell, Bob R.; Sklad, Philip S

    2006-01-01

    Expanding world economic prosperity and probable peaking of conventional petroleum production in the coming decades require efforts to increase the efficiency of, and the development of alternatives to, petroleum-based fuels used in automotive transportation. North America has been aggressively pursuing both approaches for over ten years. Mainly as a result of lower prices due to global sourcing, magnesium has recently emerged as a serious candidate for lightweighting, and thus increasing the fuel efficiency of, automotive transportation. Automotive vehicles produced in North America currently use more Mg than vehicles produced elsewhere in the world, but the amounts per vehicle are very small in comparison to other materials such as steel, aluminum and plastics. The reasons, besides price, are primarily a less-developed state of technology for Mg in automotive transportation applications and lack of familiarity by the vehicle manufacturers with the material. This paper reviews some publicly-known, recent, present and future North American research and development activities in Mg for automotive applications.

  1. Landslide triggering-thickness susceptibility, a simple proxy for landslide hazard? A test in the Mili catchment (North-Eastern Sicily, Italy)

    NASA Astrophysics Data System (ADS)

    Lombardo, Luigi; Fubelli, Giandomenico; Amato, Gabriele; Bonasera, Mauro; Mai, Martin

    2016-04-01

    This study implements a landslide triggering-thickness susceptibility approach in order to investigate the landslide scenario in the catchment of Mili, this being located in the north-easternmost sector of Sicily (Italy). From a detailed geomorphological campaign, thicknesses of mobilised materials at the triggering zone of each mass movement were collected and subsequently used as a dependent variable to be analysed in the framework of spatial predictive models. The adopted modelling methodology consisted of a presence-only learning algorithm which differently from classic presence-absence methods does not rely on stable conditions in order to derive functional relationships between dependent and independent variables. The dependent was pre-processed by reclassifying the crown thickness spectrum into a binary condition expressing thick (values equal or greater than 1m) and thin (values less than 1m) landslide crown classes. The explanatory variables were selected to express triggering-thickness dependency at different scales, these being in close proximity to the triggering point through primary and secondary attributes from a 2m-cell side Lidar HRDEM, at a medium scale through vegetation indexes from multispectral satellite images (ASTER) and a coarser scale through a geological, land use and tectonic maps. The choice of a presence-only approach allowed to effectively discriminate between the two types of landslide thicknesses at the triggering zone, producing excellent prediction skills associated with relatively low variances across a set of 50 randomly generated replicates. In addition, the role of each predictor was assessed for the two considered classes as relevant differences arose in terms of their contribution to the final models. In this regard, predictor importance, Jack-knife tests and response curves were used to assess the reliability of the models together with their geomorphological reasonability. This work attempts to capitalize on fieldwork data

  2. Participatory Research in North America; A Perspective on Participatory Research in Latin America; Participatory Research in Southern Europe.

    ERIC Educational Resources Information Center

    Gaventa, John; And Others

    1988-01-01

    The authors present perspectives on the employment of participatory research techniques in three areas: (1) North America (Gaventa); (2) Latin America (de Souza); and (3) Southern Europe (Orefice). Discussion focuses on participatory research strategies for popular groups, purposes and considerations regarding participatory research, and the role…

  3. Water quality in sugar catchments of Queensland.

    PubMed

    Rayment, G E

    2003-01-01

    Water quality condition and trend are important indicators of the impact of land use on the environment, as degraded water quality causes unwelcome changes to ecosystem composition and health. These concerns extend to the sea, where discharges of nutrients, sediments and toxicants above natural levels are unwelcome, particularly when they drain to the Great Barrier Reef World Heritage Area and other coastal waters of Queensland. Sugarcane is grown in 26 major river catchments in Queensland, most in environmentally sensitive areas. This puts pressure on the Queensland Sugar Industry to manage the land in ways that have minimum adverse off-site impacts. Sugar researchers including CRC Sugar have been associated with water quality studies in North Queensland. These include investigations and reviews to assess the role of groundwater as a pathway for nitrate loss from canelands in the Herbert Catchment, to find causes of oxygen depletion in water (including irrigation runoff) from Ingham to Mackay, to use residues of superseded pesticides as indicators of sediment loss to the sea, and to assemble information on water quality pressure and status in sugar catchments. Key findings, plus information on input pressures are described in this paper, and areas of concern and opportunities discussed. PMID:14653632

  4. Understanding of research, genetics and genetic research in a rapid ethical assessment in north west Cameroon

    PubMed Central

    Kengne-Ouafo, Jonas A.; Millard, James D.; Nji, Theobald M.; Tantoh, William F.; Nyoh, Doris N.; Tendongfor, Nicholas; Enyong, Peter A.; Newport, Melanie J.; Davey, Gail; Wanji, Samuel

    2016-01-01

    Background There is limited assessment of whether research participants in low-income settings are afforded a full understanding of the meaning of medical research. There may also be particular issues with the understanding of genetic research. We used a rapid ethical assessment methodology to explore perceptions surrounding the meaning of research, genetics and genetic research in north west Cameroon. Methods Eleven focus group discussions (including 107 adults) and 72 in-depth interviews were conducted with various stakeholders in two health districts in north west Cameroon between February and April 2012. Results Most participants appreciated the role of research in generating knowledge and identified a difference between research and healthcare but gave varied explanations as to this difference. Most participants' understanding of genetics was limited to concepts of hereditary, with potential benefits limited to the level of the individual or family. Explanations based on supernatural beliefs were identified as a special issue but participants tended not to identify any other special risks with genetic research. Conclusion We demonstrated a variable level of understanding of research, genetics and genetic research, with implications for those carrying out genetic research in this and other low resource settings. Our study highlights the utility of rapid ethical assessment prior to complex or sensitive research. PMID:25969503

  5. LLNL Middle East and North Africa research database

    SciTech Connect

    Ruppert, S.D.; Hauk, T.F.; Leach, R.

    1997-07-15

    The Lawrence Livermore National Laboratory (LLNL) CTBT R{ampersand}D program has made significant progress assembling a comprehensive seismic database (DB) for events and derived parameters in the Middle East and North Africa (ME/NA). The LLNL research DB provides not only a coherent framework in which store and organize large volumes of collected seismic waveforms and associated event parameter information but also provides an efficient data processing/research environment. The DB is designed to be flexible and extensible in order to accommodate the large volumes of data in diverse formats from many sources in addition to maintaining detailed quality control and metadata. Researchers can make use of the relational nature of the DB and interactive analysis tools to quickly and efficiently process large volumes of data. Seismic waveforms have been systematically collected form a wide range of local and regional networks using numerous earthquake bulletins and converted a common format based on CSS3.O while undergoing quality control and corrections of errors. By combining traveltime observations, event characterization studies, and regional wave-propagation studies of the LLNL CTBT team, we are assembling a library of ground truth information and event location correction surfaces required to support the ME/NA regionalization program. Corrections and parameters distilled from the LLNL research DB will provide needed contributions to the DOE knowledge base for the ME/NA region and enable the USNDC and IDC to effectively verify CTBT compliance.

  6. Impact of spatial and temporal resolution of rainfall inputs on urban hydrodynamic modelling outputs: A multi-catchment investigation

    NASA Astrophysics Data System (ADS)

    Ochoa-Rodriguez, Susana; Wang, Li-Pen; Gires, Auguste; Pina, Rui Daniel; Reinoso-Rondinel, Ricardo; Bruni, Guendalina; Ichiba, Abdellah; Gaitan, Santiago; Cristiano, Elena; van Assel, Johan; Kroll, Stefan; Murlà-Tuyls, Damian; Tisserand, Bruno; Schertzer, Daniel; Tchiguirinskaia, Ioulia; Onof, Christian; Willems, Patrick; ten Veldhuis, Marie-Claire

    2015-12-01

    Urban catchments are typically characterised by high spatial variability and fast runoff processes resulting in short response times. Hydrological analysis of such catchments requires high resolution precipitation and catchment information to properly represent catchment response. This study investigated the impact of rainfall input resolution on the outputs of detailed hydrodynamic models of seven urban catchments in North-West Europe. The aim was to identify critical rainfall resolutions for urban catchments to properly characterise catchment response. Nine storm events measured by a dual-polarimetric X-band weather radar, located in the Cabauw Experimental Site for Atmospheric Research (CESAR) of the Netherlands, were selected for analysis. Based on the original radar estimates, at 100 m and 1 min resolutions, 15 different combinations of coarser spatial and temporal resolutions, up to 3000 m and 10 min, were generated. These estimates were then applied to the operational semi-distributed hydrodynamic models of the urban catchments, all of which have similar size (between 3 and 8 km2), but different morphological, hydrological and hydraulic characteristics. When doing so, methodologies for standardising model outputs and making results comparable were implemented. Results were analysed in the light of storm and catchment characteristics. Three main features were observed in the results: (1) the impact of rainfall input resolution decreases rapidly as catchment drainage area increases; (2) in general, variations in temporal resolution of rainfall inputs affect hydrodynamic modelling results more strongly than variations in spatial resolution; (3) there is a strong interaction between the spatial and temporal resolution of rainfall input estimates. Based upon these results, methods to quantify the impact of rainfall input resolution as a function of catchment size and spatial-temporal characteristics of storms are proposed and discussed.

  7. Studies in Teaching: 2002 Research Digest. Research Projects Presented at Annual Research Forum (Winston-Salem, North Carolina, December 2002)

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    2002-01-01

    This document presents the of an annual educational research forum held at Wake Forest University (Winston-Salem, North Carolina) on December 11, 2002. A table of contents and 27 research studies of high school teaching are included. Studies include: Effects of the Earth/Environmental Science Requirement on High School Science Enrollment in North…

  8. Experimental program to stimulate competitive energy research in North Dakota: Summary and significance of DOE Trainee research

    SciTech Connect

    Boudjouk, Philip

    1999-07-01

    The general goals of the North Dakota DOE/EPSCoR Program are to enhance the capabilities of North Dakota's researchers to conduct nationally competitive energy-related research and to develop science and engineering human resources to meet current and future needs in energy-related areas. Doctoral students were trained and energy research was conducted.

  9. LLNL Middle East and North Africa research database

    SciTech Connect

    Dodge, D; Hauk, T; Moore, R M; O'Boyle, J; Ruppert, S

    1999-07-23

    The Lawrence Livermore National Laboratory (LLNL) Comprehensive Nuclear-Test-Ban Treaty Research and Development (CTBT R and D) program has made significant progress populating a comprehensive seismic research database (RDB) for seismic events and derived research products in the Middle East and North Africa (MENA). Our original ME/NA study region has enlarged and is now defined as an area including the Middle East, Africa, Europe, Southwest Asia, the Former Soviet Union and the Scandinavian/Arctic region. The LLNL RDB will facilitate calibration of all International Monitoring System (IMS) stations (primary and auxiliary) or their surrogates (if not yet installed) as well as a variety of gamma stations. The RDB provides not only a coherent framework in which to store and organize large volumes of collected seismic waveforms and associated event parameter information, but also provides an efficient data processing/research environment for deriving location and discrimination correction sur faces and capabilities. In order to accommodate large volumes of data from many sources with diverse formats the RDB is designed to be flexible and extensible in addition to maintaining detailed quality control information and associated metadata. Station parameters, instrument responses, phase pick information, and event bulletins were compiled and made available through the RDB. For seismic events in the MENA region occurring between 1976 and 1999, we have systematically assembled, quality checked and organized event waveforms; continuous seismic data from 1990 to present are archived for many stations. Currently, over 11,400 seismic events and 1.2 million waveforms are maintained in the RDB and made readily available to researchers. In addition to open sources of seismic data, we have established collaborative relationships with several ME/NA countries that have yielded additional ground truth and broadband waveform data essential for regional calibration and capability

  10. The North Wyke Farm Platform, a UK national capability for research into sustainability of temperate agricultural grassland management: progress and developments

    NASA Astrophysics Data System (ADS)

    Harris, Paul; Dungait, Jennifer; Griffith, Bruce; Shepherd, Anita; Sint, Hadewij; Blackwell, Martin; Cardenas, Laura; Collins, Adrian; Goulding, Keith; Lee, Michael; Orr, Robert

    2015-04-01

    The North Wyke Farm Platform (NWFP) at Rothamsted Research in the South-West of England, is a large, farm-scale experiment for collaborative research, training and knowledge exchange in agro-environmental sciences; with the aim of addressing agricultural productivity and ecosystem responses to different management practices. The 63 ha NWFP site, captures the spatial and/or temporal data necessary to develop a better understanding of the dynamic processes and underlying mechanisms that can be used to model how agricultural grassland systems respond to different management inputs. Here, via beef and sheep production, the underlying principle is to manage each of three farmlets (each consisting of five man-made, hydrologically-isolated sub-catchments) in three contrasting ways: (i) improvement through use of mineral fertilizers; (ii) improvement through use of legumes; and (iii) improvement through innovation. The connectivity between the timing and intensity of the different management operations, together with the transport of nutrients and potential pollutants from the NWFP is evaluated using various data collection and data modelling exercises. The primary data collection strategy involves the use of a ground-based, wireless sensor network, where in each of the fifteen sub-catchments, water characteristics such as flow, turbidity and chemistry are measured at a flume laboratory that captures the sub-catchment's water drainage (via a system of directed French drains). This sensor network also captures: precipitation, soil moisture and soil temperature data for each sub-catchment; greenhouse gas data across key subsets of the fifteen sub-catchments; and meteorological data (other than precipitation) at a single site only (representative of the NWFP site, as a whole). Such high temporal resolution data sets (but with limited spatial resolution) are coupled with a secondary data collection strategy, for high spatial resolution data sets (but with limited temporal

  11. Middle East, North Africa and Western Eurasia Seismic Research Database

    SciTech Connect

    O'Boyle, J L; Ruppert, S D; Hauk, T F; Dodge, D A; Ganzberger, M D; Ryall, F

    2003-07-14

    The National Nuclear Security Administration (NNSA) Ground-Based Nuclear Explosion Monitoring Research and Engineering (GNEM R&E) Program at Lawrence Livermore National Laboratory (LLNL) has made significant progress populating a comprehensive Seismic Research Database (SRDB) used for deriving seismic calibration parameters for the Middle East, North Africa and Western Eurasia (ME/NA/WE) regions. In addition to an overview of select individual information products, we present an overview of our visualization, integration, validation, and organizational processes. Development of these processes and the LLNL SRDB was necessitated by both the very large amount of data and information involved (over 15 terabytes) and the varied data and research result formats utilized. The LLNL SRDB allows for the collection of raw and contextual seismic data used in research, provides an interface for researchers to access data, provides a framework to store research results and integrate datasets, and supports assembly, integration and dissemination of datasets to the NNSA Knowledge Base (KB). The LLNL SRDB is a flexible and extensible framework consisting of a relational database (RDB), Geographical Information System (GIS), and associated product/data visualization and data management tools. This framework is designed to accommodate large volumes of data in diverse formats from many sources (both in-house-derived research and integrated contractor products), in addition to maintaining detailed quality control and metadata. In order to efficiently organize information within the LLNL SRDB, it was necessary to automate procedures needed to create and update database tables, but a large effort is still required by technicians and scientists to load special datasets, review results of automated processing and resolve quality issues. The LLNL SRDB currently has 3 million reconciled event origins and arrivals from several global, regional and local seismic bulletins and 30 million

  12. Recent Trends in Soil Science and Agronomy Research in the Northern Great Plains of North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The book “Recent Trends in Soil Science and Agronomy Research in the Northern Great Plains of North America” summarizes published research in soil science and agronomy from various field experiments conducted in the soil-climatic/agro-ecological regions of the Northern Great Plains of North America....

  13. Quantitative catchment profiling to apportion faecal indicator organism budgets for the Ribble system, the UK's sentinel drainage basin for Water Framework Directive research.

    PubMed

    Stapleton, C M; Wyer, M D; Crowther, J; McDonald, A T; Kay, D; Greaves, J; Wither, A; Watkins, J; Francis, C; Humphrey, N; Bradford, M

    2008-06-01

    Under the EU Water Framework Directive (WFD) 20/60/EC and the US Federal Water Pollution Control Act 2002 management of water quality within river drainage basins has shifted from traditional point-source control to a holistic approach whereby the overall contribution of point and diffuse sources of pollutants has to be considered. Consequently, there is a requirement to undertake source-apportionment studies of pollutant fluxes within catchments. The inclusion of the Bathing Water Directive (BWD), under the list of 'protected areas' in the WFD places a requirement to control sources of faecal indicator organisms within catchments in order to achieve the objectives of both the BWD (and its revision - 2006/7/EC) and the WFD. This study was therefore initiated to quantify catchment-derived fluxes of faecal indicator compliance parameters originating from both point and diffuse sources. The Ribble drainage basin is the single UK sentinel WFD research catchment and discharges to the south of the Fylde coast, which includes a number of high profile, historically non-compliant, bathing waters. Faecal indicator concentrations (faecal coliform concentrations are reported herein) were measured at 41 riverine locations, the 15 largest wastewater treatment works (WwTWs) and 15 combined sewer overflows (CSOs) across the Ribble basin over a 44-day period during the 2002 bathing season. The sampling programme included targeting rainfall-induced high flow events and sample results were categorised as either base flow or high flow. At the riverine sites, geometric mean faecal coliform concentrations showed statistically significant elevation at high flow compared to base flow. The resultant faecal coliform flux estimates revealed that over 90% of the total organism load to the Ribble Estuary was discharged by sewage related sources during high flow events. These sewage sources were largely related to the urban areas to the south and east of the Ribble basin, with over half the

  14. Synergies between geomorphic hazard and risk and sediment cascade research fields: exploiting geomorphic processes' susceptibility analyses to derive potential sediment sources in the Oltet, river catchment, southern Romania

    NASA Astrophysics Data System (ADS)

    Jurchescu, Marta-Cristina

    2015-04-01

    Identifying sediment sources and sediment availability represents a major problem and one of the first concerns in the field of sediment cascade. This paper addresses the on-site effects associated with sediment transfer, investigating the degree to which studies pertaining to the field of geomorphic hazard and risk research could be exploited in sediment budget estimations. More precisely, the paper investigates whether results obtained in assessing susceptibility to various geomorphic processes (landslides, soil erosion, gully erosion) could be transferred to the study of sediment sources within a basin. The study area is a medium-sized catchment (> 2400 km2) in southern Romania encompassing four different geomorphic units (mountains, hills, piedmont and plain). The region is highly affected by a wide range of geomorphic processes which supply sediments to the drainage network. The presence of a reservoir at the river outlet emphasizes the importance of estimating sediment budgets. The susceptibility analyses are conducted separately for each type of the considered processes in a top-down framework, i.e. at two different scales, using scale-adapted methods and validation techniques in each case, as widely-recognized in the hazard and risk research literature. The analyses start at a regional scale, which has in view the entire catchment, using readily available data on conditioning factors. In a second step, the suceptibility analyses are carried out at a medium scale for selected hotspot-compartments of the catchment. In order to appraise the extent to which susceptibility results are relevant in interpreting sediment sources at catchment scale, scale-induced differences are analysed in the case of each process. Based on the amount of uncertainty revealed by each regional-scale analysis in comparison to the medium-scale ones, decisions are made on whether the first are acceptable to the aim of identifying potential sediment source areas or if they should be

  15. Issues/Higher Education/Institutional Research. NCAIR Proceedings. Fifth Annual Meeting of the North Carolina Association for Institutional Research (Asheville, North Carolina, November 2-3, 1977).

    ERIC Educational Resources Information Center

    Brown, Charles I., Ed.

    Proceedings from the fifth annual meeting of the North Carolina Association for Institutional Research (NCAIR) focus on issues affecting higher education and the relationship of these issues to the institutional research function. Included are general session addresses by Charles A. Lyons and Dick Robinson that discuss the implications of Judge…

  16. A new, catchment-scale model for simulating methyl and total mercury in soils and surface waters

    NASA Astrophysics Data System (ADS)

    Futter, M. N.; Poste, A. E.; Whitehead, P. G.; Dillon, P. J.

    2012-04-01

    Mercury (Hg) is a potent and persistent neurotoxin. It is subject to long-range atmospheric transport, accumulates in catchment soils, and can pose health risks to humans and animals both at the point of use as well as in remote locations. Elevated concentrations of methyl mercury (MeHg) in fish are related to atmospheric Hg deposition and have resulted in fish consumption advisories in many parts of North America and Fennoscandia. After more than 150 years of elevated Hg deposition in Europe and North America, there remains a large inventory of Hg in the terrestrial catchments of lakes, which continues to be exported to receiving waters despite decreasing atmospheric inputs. While a substantial Hg pool exists in boreal catchment soils, fluxes of Hg from catchments via stream runoff tend to be much lower than atmospheric Hg inputs. Terrestrial catchments receiving similar atmospheric Hg inputs can have markedly different patterns of Hg output in stream water. Considering the importance of catchment processes in determining Hg flux to lakes and subsequent MeHg concentrations in fish, there is a need to characterize Hg cycling and transport in boreal and temperate forest-covered catchments. We present a new, catchment-scale, process-based dynamic model for simulating Hg in soils and surface waters. The Integrated Catchments Model for Mercury (INCA-Hg) simulates transport of gaseous, dissolved and solid Hg and transformations between elemental (Hg0), ionic (Hg(II)) and MeHg in natural and semi-natural landscapes. The mathematical description represents the model as a series of linked, first-order differential equations describing chemical and hydrological processes in catchment soils and waters which control surface water Hg dynamics and subsequent fluxes to lakes and other receiving waters. The model simulates daily time series between one and one hundred years long and can be applied to catchments ranging in size from <1 to ~10000 km2. Here we present applications

  17. OVERVIEW OF THE NORTH AMERICAN RESEARCH STRATEGY FOR TROPOSPHERIC OZONE

    EPA Science Inventory

    Tropospheric ozone (O3) and related products of photochemical smog, have been the subject of repeated control attempts for nearly 30 years in portions of North America. hese trace gases are known to be harmful to humans, animals, vegetation, and materials. s growth and industrial...

  18. Analysing the role of abandoned agricultural terraces on flood generation in a set of small Mediterranean mountain research catchments (Vallcebre, NE Spain)

    NASA Astrophysics Data System (ADS)

    Gallart, Francesc; Llorens, Pilar; Pérez-Gallego, Nuria; Latron, Jérôme

    2016-04-01

    The Vallcebre research catchments are located in NE Spain, in a middle mountain area with a Mediterranean sub-humid climate. Most of the bedrock consists of continental red lutites that are easily weathered into loamy soils. This area was intensely used for agriculture in the past when most of the sunny gentle hillslopes were terraced. The land was progressively abandoned since the mid-20th Century and most of the fields were converted to meadows or were spontaneously forested. Early studies carried out in the terraced Cal Parisa catchment demonstrated the occurrence of two types of frequently saturated areas, ones situated in downslope locations with high topographic index values, and the others located in the inner parts of many terraces, where the shallow water table usually outcrops due to the topographical modifications linked to terrace construction. Both the increased extent of saturated areas and the role of a man-made elementary drainage system designed for depleting water from the terraces suggested that terraced areas would induce an enhanced hydrological response during rainfall events when compared with non-terraced hillslopes. The response of 3 sub-catchments, of increasing area and decreasing percentage of terraced area, during a set of major events collected during over 15 years has been analysed. The results show that storm runoff depths were roughly proportional to precipitations above 30 mm although the smallest catchment (Cal Parisa), with the highest percentage of terraces, was able to completely buffer rainfall events of 60 mm in one hour without any runoff when antecedent conditions were dry. Runoff coefficients depended on antecedent conditions and peak discharges were weakly linked to rainfall intensities. Peak lag times, peak runoff rates and recession coefficients were similar in the 3 catchments; the first variable values were in the range between Hortonian and saturation overland flow and the two last ones were in the range of

  19. Human impacts on river water quality- comparative research in the catchment areas of the Tone River and the Mur River-

    NASA Astrophysics Data System (ADS)

    Kogure, K.

    2013-12-01

    Human activities in river basin affect river water quality as water discharges into river with pollutant after we use it. By detecting pollutants source, pathway, and influential factor of human activities, it will be possible to consider proper river basin management. In this study, material flow analysis was done first and then nutrient emission modeling by MONERIS was conducted. So as to clarify land use contribution and climate condition, comparison of Japanese and European river basin area has been made. The model MONERIS (MOdelling Nutrient Emissions in RIver Systems; Behrendt et al., 2000) was applied to estimate the nutrient emissions in the Danube river basin by point sources and various diffuse pathways. Work for the Mur River Basin in Austria was already carried out by the Institute of Water Quality, Resources and Waste Management at the Vienna University of Technology. This study treats data collection, modelling for the Tone River in Japan, and comparative analysis for these two river basins. The estimation of the nutrient emissions was carried out for 11 different sub catchment areas covering the Tone River Basin for the time period 2000 to 2006. TN emissions into the Tone river basin were 51 kt/y. 67% was via ground water and dominant for all sub catchments. Urban area was also important emission pathway. Human effect is observed in urban structure and agricultural activity. Water supply and sewer system make urban water cycle with pipeline structure. Excess evapotranspiration in arable land is also influential in water cycle. As share of arable land is 37% and there provides agricultural products, it is thought that N emission from agricultural activity is main pollution source. Assumption case of 10% N surplus was simulated and the result was 99% identical to the actual. Even though N surplus reduction does not show drastic impact on N emission, it is of importance to reduce excess of fertilization and to encourage effective agricultural activity

  20. RESEARCH PROSPECTIVES FOR DOLPHIN MORTALITIES IN NORTH AMERICA

    EPA Science Inventory

    The Second Gulf Breeze Symposium sponsored by EPA's Center for Marine and Estuarine Disease Research focused on scientific research related to dolphin mortalities. uring the symposium, four groups were formed to discuss and evaluate current scientific information, research strate...

  1. Topographical and Hydrological Influences on the Spatial Distribution of Mercury at the Catchment Scale

    NASA Astrophysics Data System (ADS)

    Gunda, T.; Converse, A.; Riscassi, A.; Scanlon, T. M.

    2009-12-01

    Inorganic forms of mercury (Hg) can be converted through natural processes into methylmercury, a highly potent neurotoxin that can bioaccumulate in food chains and pose a risk to human health. Although Hg can enter aquatic environments through direct deposition, the predominant source tends to be mobilized Hg deposited in nearby terrestrial systems. Therefore, understanding the complex intermediate Hg cycling in vegetation and soils is crucial to predicting its presence in water bodies and potential for bioaccumulation. While prior studies have revealed dependence of Hg distribution on forest types and soil characteristics, less attention has been given to the role of aspect and hydrological factors on Hg deposition and consequent spatial distribution within catchments. My research addresses this by conducting a litterfall and soil sampling study to assess Hg spatial distribution within two paired catchments: northwest-facing North Fork Dry Run and southeast-facing Hannah Run. Litterfall and soil samples collected through a random stratified sampling process were analyzed for total Hg concentrations using a Cold Vapor Atomic Fluorescence Spectrometry. An analysis of variance conducted on leaf litter and soil Hg concentrations revealed that: (1) Hg accumulation in soils was significantly greater in the northwest-facing catchment than in the south-east facing catchment, while Hg accumulation in leaves was not found to differ, and (2) within each catchment the likelihood of saturation was not found to play a significant role in governing Hg accumulation in soils. Higher Hg levels in the soils of North Forth Dry Run could be attributable to predominant wind direction from sources of Hg (i.e., coal-burning power plants). Within catchments, lack of appreciable Hg deposition resulted in statistically insignificant variation amongst topographic index classes. The results of this study reveal the potential implications of mountainous terrains in distributing Hg arising from

  2. Adult Education Research: A Comparison of North American and British Theory and Practice.

    ERIC Educational Resources Information Center

    Brookfield, Stephen

    1982-01-01

    Finding that British researchers are believed to use qualitative methods while North Americans favor quantitative measurement in adult education enquiry, the author examines substantive research concerns and research publication in the United States, Britain, and Canada and concludes that there is some validity to the stereotype. (Availability:…

  3. NCIP Manual. Manual for the North American Inventory of Research Library Collections. Revised Edition.

    ERIC Educational Resources Information Center

    Reed-Scott, Jutta

    The Association of Research Libraries' Office of Management Services (OMS), working with the Research Libraries Group, Inc. (RLG), began the North American Collections Inventory Project (NCIP) in July 1983 as a cooperative effort intended eventually to involve research libraries throughout the United States and Canada. The project's long-term goal…

  4. NARVAL North - Remote Sensing of Postfrontal Convective Clouds and Precipitation over the North Atlantic with the Research Aircraft HALO

    NASA Astrophysics Data System (ADS)

    Klepp, Christian; Ament, Felix; Bakan, Stephan; Crewell, Susanne; Hagen, Martin; Hirsch, Lutz; Jansen, Friedhelm; Konow, Heike; Mech, Mario; Pfeilsticker, Klaus; Schäfler, Andreas; Stevens, Bjorn

    2014-05-01

    The new German research aircraft HALO (High Altitude and Long Range Research Aircraft) became recently available for measurement flights in atmospheric research. It's capacity of measuring from a high altitude vertical profiles of all components of atmospheric water - like vapor, liquid and ice, in both cloud and precipitation forms, as well as the aerosol particles upon which cloud droplets form - makes it a unique research platform. The aircraft, equipped with advanced radiometers, radar and lidar technology, the HALO Microwave Package (HAMP), is an initiative by German climate and environmental research institutions and is operated by the German Aerospace Center (DLR). One of the first major missions to exploit the capabilities of HALO was conducted for the NARVAL project (Next-generation Aircraft Remote-Sensing for Validation Studies) during January 2014. After studying subtropical clouds one month before in the first NARVAL phase, the interest of NARVAL North focused on the study of cold air convection and precipitation in the form of rain and snow. Based at Keflavik airport (Iceland), several flights were conducted to examine the specific small-scale precipitation structures behind the backsides of cold fronts over the North Atlantic. This should help to narrow the gap in the understanding of substantial differences between satellite observations and model calculations in such situations. First data analysis of these measurements indicate promising results. The poster will describe the HALO instrument packages as well as the collected observations during the campaign and will present preliminary scientific findings.

  5. Evaluating the Impacts of Unexpected Forest Disturbances on Paired Catchment Calibrations of Sediment Yield and Turbidity

    NASA Astrophysics Data System (ADS)

    Herlein, K.; Silins, U.; Williams, C.; Wagner, M. J.; Martens, A. M.

    2015-12-01

    The paired catchment approach of studying the impacts of disturbance on catchment hydrology remains as perhaps the most powerful approach for direct verification of catchment scale impacts from disturbance. However, paired catchment studies are also dependent on the stability of the relationships between treated and reference catchments during calibration and evaluation periods. A long-term paired catchment study of forest harvest impacts on sediment yield and turbidity in the Rocky Mountains of southwestern Alberta, Canada has a robust 11-year pre-treatment data record. The study intends to evaluate three alternative logging practices: clear-cutting, strip-shelterwood, and partial cutting. 3 sub-catchments in Star Creek (1035 ha) underwent harvest treatments while North York Creek (865 Ha) serves as the reference. The objective of this particular study was to explore the potential effects of unplanned and unanticipated watershed changes in two watersheds during an 11-year calibration. Sediment yield (kg ha-1 d-1) and turbidity (NTU) were monitored throughout the calibration period (2004-2014) prior to the 2015 harvest in Star Creek. Two unanticipated disturbances including backcountry trail rehabilitation in North York (2010) followed by a >100 year storm event in both watersheds in June 2013 may have affected the sediment yield and turbidity calibration relationships. Analysis of covariance (ANCOVA) was used to evaluate the effects of this trail rehabilitation and flooding by comparing the calibration relationships before and after these disturbances. Despite qualitative field observations of periodically affected sediment regimes, no impact on pre- or post- calibration relationships was observed. Backcountry trail rehabilitation in North York (p=0.904 and 0.416 for sediment yield and turbidity, respectively) or flooding in both watersheds (p=0.364 and 0.204 for sediment yield and turbidity, respectively) did not produce significant changes to the calibrations

  6. Studies in Teaching. 1995 Research Digest. Papers Presented at the Annual Research Forum (Winston-Salem, North Carolina, December 1995).

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    This is a collection of papers reporting student research projects at the Annual Research Forum, Department of Education, Wake Forest University (North Carolina). They include: "Student Interest in Studying World History in Relation to Current Events" (Conan Arthur); "Perceptions of High School Student Athletes and Athletics" (Edward Barrett);…

  7. NASA/FAA North Texas Research Station Overview

    NASA Technical Reports Server (NTRS)

    Borchers, Paul F.

    2012-01-01

    NTX Research Staion: NASA research assets embedded in an interesting operational air transport environment. Seven personnel (2 civil servants, 5 contractors). ARTCC, TRACON, Towers, 3 air carrier AOCs(American, Eagle and Southwest), and 2 major airports all within 12 miles. Supports NASA Airspace Systems Program with research products at all levels (fundamental to system level). NTX Laboratory: 5000 sq ft purpose-built, dedicated, air traffic management research facility. Established data links to ARTCC, TRACON, Towers, air carriers, airport and NASA facilities. Re-configurable computer labs, dedicated radio tower, state-of-the-art equipment.

  8. An approach for aggregating upstream catchment information to support research and management of fluvial systems across large landscapes.

    PubMed

    Tsang, Yin-Phan; Wieferich, Daniel; Fung, Kuolin; Infante, Dana M; Cooper, Arthur R

    2014-01-01

    The growing quality and availability of spatial map layers (e.g., climate, geology, and land use) allow stream studies, which historically have occurred over small areas like a single watershed or stream reach, to increasingly explore questions from a landscape perspective. This large-scale perspective for fluvial studies depends on the ability to characterize influences on streams resulting from throughout entire upstream networks or catchments. While acquiring upstream information for a single reach is relatively straight-forward, this process becomes demanding when attempting to obtain summaries for all streams throughout a stream network and across large basins. Additionally, the complex nature of stream networks, including braided streams, adds to the challenge of accurately generating upstream summaries. This paper outlines an approach to solve these challenges by building a database and applying an algorithm to gather upstream landscape information for digitized stream networks. This approach avoids the need to directly use spatial data files in computation, and efficiently and accurately acquires various types of upstream summaries of landscape information across large regions using tabular processing. In particular, this approach is not limited to the use of any specific database software or programming language, and its flexibility allows it to be adapted to any digitized stream network as long as it meets a few minimum requirements. This efficient approach facilitates the growing demand of acquiring upstream summaries at large geographic scales and helps to support the use of landscape information in assisting management and decision-making across large regions. PMID:25392769

  9. Recruiting Underserved Mothers to Medical Research: Findings from North Carolina

    PubMed Central

    Spears, Chaya R.; Sandberg, Joanne C.; O’Neill, Jenna L.; Grzywacz, Joseph G.; Howard, Timothy D.; Feldman, Steven R.; Arcury, Thomas A.

    2014-01-01

    Representative samples are required for ethical, valid, and useful health research. Yet, recruiting participants, especially from historically underserved communities, can be challenging. This paper presents findings from in-depth interviews with 40 mothers about factors that might influence their willingness to participate or allow their children to participate in medical research. Saliency analysis organizes the findings. Frequent and important salient themes about research participation included concerns that it might cause participants harm, hope that participants might gain a health benefit, and recognition that time and transportation resources could limit participation. Ultimately, we propose that a theoretical model, such as the Theory of Planned Behavior (TPB), will facilitate more systematic evaluation of effective methods for recruitment and retention of participants in medical research. Future research should explore the utility of such a model for development of effective recruitment and retention strategies. PMID:24185171

  10. 2012 North Plains research field 12-200 limited irrigation corn production study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    2012 represented the third sequential year of research regarding the limited irrigation 12-200 corn production assessment study at the North Plains Research Field (NPRF) with the yield results being improved from that of the 2011 season but less than of the 2010 season. The study's purpose was to ev...

  11. Spectral Analysis in Catchment Hydrology and Geochemistry

    NASA Astrophysics Data System (ADS)

    Kirchner, J. W.; Feng, X.; Renshaw, C. E.; Neal, C.

    2001-12-01

    Spectral analysis of chemical tracer time series can be used to probe the internal workings of catchments. It has recently been shown that catchments act as fractal filters for inert chemical tracers like chloride, converting "white noise" rainfall chemistry inputs into fractal "1/f noise" runoff chemistry time series (Kirchner et al., 2000). This implies that catchments have long-tailed travel time distributions, and thus retain soluble contaminants for unexpectedly long timespans. Long-term monitoring data from North America, Britain, and Scandinavia show that this fractal behavior characterizes a wide array of catchments. How can this fractal scaling arise in such diverse settings? One can show that advection and dispersion of spatially distributed rainfall tracer inputs will generate fractal tracer time series, as long as the flow system is highly dispersive (Kirchner et al., in press). This implies that subsurface flow in small catchments is dominated by large conductivity contrasts, such as arise from macropores, fracture networks, and similar large-scale heterogeneities in subsurface conductivity. One can also use spectral methods to analyze long-term time series of water fluxes in rainfall and streamflow. Spectral analysis of hydrologic time series measures the downslope propagation of the hydraulic potential waves that mobilize runoff, whereas spectral analysis of tracer time series clocks the propagation of water itself through the catchment. Water fluxes in streamflow exhibit non-fractal scaling, instead of the fractal 1/f scaling shown by chemical tracers. These observations imply that hydrologic signals are transmitted downslope more rapidly, and with much less dispersion, than chemical tracer signals are. Thus small upland catchments transmit hydraulic potentials (which drive runoff) much less dispersively than they transport water itself. These observations provide important constraints for theoretical models of subsurface flow and transport in

  12. A North Adriatic centenarian: The marine research station at Rovinj

    NASA Astrophysics Data System (ADS)

    Zavodnik, D.

    1995-03-01

    The institute in Rovinj was founded in 1891 as the field station of the Berlin Aquarium. It soon gained in scientific importance. From 1911, it was governed by various scientific bodies, such as the ‘Kaiser-Wilhelm-Gesellschaft zur Förderung der Wissenschaften’, the ‘Reale Comitato Talassografico Italiano’, and the ‘Jugoslavenska Akademija znanosti i umjetnosti’. At present, it is a department of the ‘Ruđer Bo\\vsković’ Institute, called the ‘Center for Marine Research Rovinj’. In the past hundred years, the Rovinj station experienced several ascents and declines in its development: both in the First and Second World Wars the station's scientific equipment, research vessels, library and reference collections were dispersed, and from 1945 1948 the station was closed. But in “happier” periods, rich support by the state and international bodies favoured the increase in research facilities and promoted interest among visiting scientists. The station has always been involved in studies of the Adriatic Sea, especially in its northern part. It contributed much to general knowledge of oceanography, of the physics and chemistry of the sea, but its paramount contribution is to various disciplines of marine biological sciences. Applied research, however, was most oriented to fisheries biology, especially shellfish culture, to resource studies, and, recently, to toxicology, bacteriology, eutrophication and pollution monitoring. The international approach in science and applied research was always favoured. At present, the Center is well equipped for complex coastal and offshore field- and laboratory research, and maintains facilities for graduate and postgraduate teaching. Scientific dissemination is also promoted by the public aquarium and professional meetings.

  13. Geographically Isolated Wetlands and Catchment Hydrology: A Modified Model Analyses

    NASA Astrophysics Data System (ADS)

    Evenson, G.; Golden, H. E.; Lane, C.; D'Amico, E.

    2014-12-01

    Geographically isolated wetlands (GIWs), typically defined as depressional wetlands surrounded by uplands, support an array of hydrological and ecological processes. However, key research questions concerning the hydrological connectivity of GIWs and their impacts on downgradient surface waters remain unanswered. This is particularly important for regulation and management of these systems. For example, in the past decade United States Supreme Court decisions suggest that GIWs can be afforded protection if significant connectivity exists between these waters and traditional navigable waters. Here we developed a simulation procedure to quantify the effects of various spatial distributions of GIWs across the landscape on the downgradient hydrograph using a refined version of the Soil and Water Assessment Tool (SWAT), a catchment-scale hydrological simulation model. We modified the SWAT FORTRAN source code and employed an alternative hydrologic response unit (HRU) definition to facilitate an improved representation of GIW hydrologic processes and connectivity relationships to other surface waters, and to quantify their downgradient hydrological effects. We applied the modified SWAT model to an ~ 202 km2 catchment in the Coastal Plain of North Carolina, USA, exhibiting a substantial population of mapped GIWs. Results from our series of GIW distribution scenarios suggest that: (1) Our representation of GIWs within SWAT conforms to field-based characterizations of regional GIWs in most respects; (2) GIWs exhibit substantial seasonally-dependent effects upon downgradient base flow; (3) GIWs mitigate peak flows, particularly following high rainfall events; and (4) The presence of GIWs on the landscape impacts the catchment water balance (e.g., by increasing groundwater outflows). Our outcomes support the hypothesis that GIWs have an important catchment-scale effect on downgradient streamflow.

  14. Towards catchment classification by means of environmental tracers and landscape analysis: The Attert catchment in Luxembourg

    NASA Astrophysics Data System (ADS)

    Wrede, S.; Pfister, L.; Krein, A.; Fenicia, F.; Bogaard, T. A.; Uhlenbrook, S.; Savenije, H. H. G.

    2010-05-01

    Until recently hydrological research has been mainly focusing on detailed investigations at small spatial scales, resulting in a set of more and more complex physically-based and spatially distributed hydrologic models. While much of the research effort today is targeted to advance these hydrological model predictions at the catchment scale, shortcomings remain to adequately capture the dominating hydrological processes across a range of scales that translate into the rainfall-runoff response of a catchment. Thus, studies addressing the fundamental relations between catchment structure and function are urgently needed, as they help catchment classification by advancing our knowledge about suitable catchment signatures and controls at different spatial and temporal scales. In our study in the nested Attert catchment in the Grand-Duchy of Luxembourg (Europe) we investigate how environmental tracer dynamics, hydrological response behavior and landscape analysis can help to identify such dominating controls on runoff generation across multiple scales. Techniques to characterize landscape structure and hydrological processes are complementary applied to identify scales in which shifts of the dominant hydrological processes occur. These dominating controls in turn provide a more integrated perspective of catchment structure and functioning that can be used for catchment classification based on functional response.

  15. 2013 North Dakota Transgenic Barley Research and FHB Nursery Report

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research continues to develop and test new transgenic plants using genes provided by collaborators. As lines are developed in Golden Promise, they are crossed to Conlon for field testing. Transgenic lines developed in Conlon are being crossed to resistant lines developed by the breeding programs. ...

  16. The Practice of Institutional Research. Proceedings of a Joint Conference of the Southern Association for Institutional Research and the North Carolina Association for Institutional Research (Charlotte, North Carolina, October 29-30, 1981).

    ERIC Educational Resources Information Center

    Martin, Mary P., Ed.; Staman, E. Michael, Ed.

    Proceedings of a 1981 joint conference sponsored by the Southern Association for Institutional Research (SAIR) and the North Carolina Association for Institutional Research are presented. The conference theme was the practice of institutional research. Contents include preconference workshop reports, speeches, abstracts of papers, and reports of…

  17. Inferring the effect of catchment complexity on mesoscale hydrologic response

    NASA Astrophysics Data System (ADS)

    FröHlich, Holger L.; Breuer, Lutz; Vaché, Kellie B.; Frede, Hans-Georg

    2008-09-01

    The effect of catchment complexity on hydrologic and hydrochemical catchment response was characterized in the mesoscale Dill catchment (692 km2), Germany. This analysis was developed using multivariate daily stream concentration and discharge data at the basin outlet, in connection with less frequently sampled catchment-wide end-member chemistries. The link between catchment-wide runoff sources and basin output was observed through a combination of concentration-discharge (C-Q) analysis and multivariate end-member projection. Subsurface stormflow, various groundwater and wastewater sources, as well as urban surface runoff emerged in catchment output chemistry. Despite the identification of multiple sources, several runoff sources observed within the catchment failed to display consistent links with the output chemistry. This failure to associate known source chemistry with outlet chemistry may have resulted from a lack of hydraulic connectivity between sources and basin outlet, from different arrival times of subbasin-scale runoff contributions, and also from an overlap of source chemistries that subsumed discrete runoff sources in catchment output. This combination of catchment heterogeneity and complexity simply suggests that the internal spatial organization of the catchment impeded the application of lumped mixing calculations at the 692 km2 outlet. Given these challenges, we suggest that in mesoscale catchment research, the potential effects of spatial organization should be included in any interpretation of highly integrated response signals, or when using those signals to evaluate numerical rainfall-runoff models.

  18. High-resolution monitoring of catchment nutrient response to the end of the 2011-2012 drought in England, captured by the demonstration test catchments

    NASA Astrophysics Data System (ADS)

    Outram, F. N.; Lloyd, C.; Jonczyk, J.; Benskin, C. McW. H.; Grant, F.; Dorling, S. R.; Steele, C. J.; Collins, A. L.; Freer, J.; Haygarth, P. M.; Hiscock, K. M.; Johnes, P. J.; Lovett, A. L.

    2013-12-01

    The Demonstration Test Catchments (DTC) project is a UK Government funded initiative to test the effectiveness of on-farm mitigation measures designed to reduce agricultural pollution without compromising farm productivity. Three distinct catchments in England have been chosen to test the efficacy of mitigation measures on working farms in small tributary sub-catchments equipped with continuous water quality monitoring stations. The Hampshire Avon in the south is a mixed livestock and arable farming catchment, the River Wensum in the east is a lowland catchment with predominantly arable farming and land use in the River Eden catchment in the north-west is predominantly livestock farming. One of the many strengths of the DTC as a national research platform is that it provides the ability to investigate catchment hydrology and biogeochemical response across different landscapes and geoclimatic characteristics, with a range of differing flow behaviours, geochemistries and nutrient chemistries. Although numerous authors present studies of individual catchment responses to storms, no studies exist of multiple catchment responses to the same rainfall event captured with in situ high-resolution nutrient monitoring at a national scale. This paper brings together findings from all three DTC research groups to compare the response of the catchments to a major storm event in April 2012. This was one of the first weather fronts to track across the country following a prolonged drought period affecting much of the UK through 2011-2012, marking an unusual meteorological transition when a rapid shift from drought to flood risk occurred. The effects of the weather front on discharge and water chemistry parameters, including nitrogen species (NO3-N and NH4-N) and phosphorus fractions (total P (TP) and total reactive P (TRP)), measured at a half-hourly time step are examined. When considered in the context of one hydrological year, flow and concentration duration curves reveal that

  19. Labor Market Returns to Community College: Evidence from North Carolina. Research Brief

    ERIC Educational Resources Information Center

    Belfield, Clive; Liu, Yuen Ting; Trimble, Madeline Joy

    2014-01-01

    In this brief, we summarize our research on the wage returns to community college pathways in North Carolina. We use detailed individual and college transcript information on approximately 830,000 students who attended community college during the 2000s. This transcript data is matched with earnings data from Unemployment Insurance records. We…

  20. Watershed Research at the North Appalachian Experimental Watershed at Coshocton, Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The North Appalachian Experimental Watershed (NAEW) at Coshocton, Ohio was established during the mid 1930s as one of the first watershed research locations in the US (other locations included Riesel, TX and Hastings, NE). The mission of the outdoor laboratory facility was to determine the effects ...

  1. Studies in Teaching: 2005 Research Digest. Research Projects Presented at Annual Research Forum (Winston-Salem, North Carolina, December 7, 2005)

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    2005-01-01

    These Proceedings document an educational research forum held at Wake Forest University (Winston-Salem, North Carolina) on December 7, 2005. Table of contents and 26 research studies of high school teaching are included. Studies include: (1) Mathematical Reasoning in Multiple Representations: Connections and Confidence (Justin Allman); (2) The…

  2. Studies in Teaching: 2007 Research Digest. Research Projects Presented at Annual Research Forum (Winston-Salem, North Carolina, December 12, 2007)

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    2007-01-01

    These Proceedings document an educational research forum held at Wake Forest University (Winston-Salem, North Carolina) on December 12, 2007. Table of contents and 23 research studies of high school teaching are included. Each paper contains a literature review, methodology, results, conclusions, and references. Studies include: (1) Cultural…

  3. Studies in Teaching: 2012 Research Digest. Action Research Projects Presented at Annual Research Forum (Winston-Salem, North Carolina, June 29, 2012)

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    2012-01-01

    This document presents the proceedings of the 17th Annual Research Forum held June 29, 2012, at Wake Forest University in Winston-Salem, North Carolina. Included herein are the following 25 action research papers: (1) "Reading and Writing": A Study Comparing the Strengths of Peer Review and Visible Author Writing Strategies (Elizabeth Behar); (2)…

  4. Studies in Teaching: 2003 Research Digest. Research Projects Presented at Annual Research Forum (Winston-Salem, North Carolina, December 10, 2003)

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    2003-01-01

    This document presents the proceedings of an annual educational research forum held at Wake Forest University (Winston-Salem, North Carolina) on December 10, 2003. A table of contents and 31 research studies of high school teaching are included. The following studies are included: (1) No, Seriously: Humor Use by High School Social Studies Teachers…

  5. Studies in Teaching: 2013 Research Digest. Action Research Projects Presented at Annual Research Forum (Winston-Salem, North Carolina, June 26, 2013)

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    2013-01-01

    This document presents the proceedings of the 18th Annual Research Forum held June 26, 2013, at Wake Forest University in Winston-Salem, North Carolina. Included are the following 13 action research papers: (1) Developing Oral Language Ability in the Secondary Spanish Classroom Using the Interpersonal and Presentational Modes of Communication…

  6. Studies in Teaching: 2011 Research Digest. Research Projects Presented at Annual Research Forum (Winston-Salem, North Carolina, June 15, 2011)

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    2011-01-01

    This document presents the proceedings of 16th Annual Research Forum held June 15, 2011, at Wake Forest University in Winston-Salem, North Carolina. Included herein are the following 25 action research papers: (1) The Effects of Prompted Math Journaling on Algebra 1 Students' Achievement and Attitudes (Heidi I. Arnold); (2) Group Work and Attitude…

  7. Studies in Teaching: 2006 Research Digest. Research Projects Presented at Annual Research Forum (Winston-Salem, North Carolina, December 6, 2006)

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    2006-01-01

    These Proceedings document an educational research forum held at Wake Forest University (Winston-Salem, North Carolina) on December 6, 2006. Table of contents and 27 research studies of high school teaching are included. Studies include: (1) A Study of Teachers' Perceptions of High School Mathematics Instructional Methods (Caroline Adkisson); (2)…

  8. Studies in Teaching: 2015 Research Digest. Action Research Projects Presented at Annual Research Forum (Winston-Salem, North Carolina, June 25, 2015)

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    2015-01-01

    This document presents the proceedings of the 20th Annual Research Forum held June 25, 2015, at Wake Forest University in Winston-Salem, North Carolina. Included are the following 21 action research papers: (1) History Lives! The Use of Simulations in a High School Social Studies Classroom (Lydia Adkins); (2) Using Francophone Music in the High…

  9. Learning Journeys: Learners' Voice. North East Learners' Views on Progress and Achievement in Literacy and Numeracy. Summary Research Report

    ERIC Educational Resources Information Center

    Gregson, Maggie; Spedding, Trish; Banks, Andy; Stewart, Jennifer; Staley, Jim; Edmonds, Catherine

    2004-01-01

    This report describes the processes and findings of a north east Learning and Skills Development Agency (LSDA) research project. This was a collaborative research study, which followed from a similar, much larger project in the north west, which looked into how learners view their own progress and achievement in the acquisition of literacy and…

  10. Runoff generation mechanism at two distinct headwater catchments - isotopic evidence

    NASA Astrophysics Data System (ADS)

    Dohnal, Michal; Votrubová, Jana; Šanda, Martin; Tesař, Miroslav; Vogel, Tomáš; Dušek, Jaromír

    2016-04-01

    Data from two headwater catchments indicate considerably different runoff formation mechanisms. The contributions of different surface and subsurface runoff mechanisms to the catchment discharge formation at these two small forested headwater catchments are studied with help of the natural isotopic signatures of the observed fluxes. The Uhlirska catchment (1.78 sq. km, Jizera Mts., Czech Republic) is situated in headwater area of Cerna Nisa stream. Deluviofluvial granitic sediments in the valley bottom areas (riparian zones/wetlands) are surrounded by gentle hillslopes with shallow soils developed on crystalline bedrock. The Liz catchment (0.99 sq. km, Bohemian Forest, Czech Republic) belongs to hillslope-type catchments without riparian zones situated in headwater area of Volynka River. The soil at Liz is developed on biotite paragneiss bedrock. Autocorrelation analysis of the measured catchment discharge rates reveals different hydrograph characteristics for each of the two catchments. Estimated autocorrelation lengths differ by an order of magnitude. Variations of oxygen-18 isotope concentrations in precipitation, groundwater and streamflow were analyzed. Several significant rainfall-runoff events at each of the two catchments were analyzed in detail. These events exhibit substantial difference in isotopic compositions of event and pre-event water, which facilitates hydrograph separation. Clockwise and counterclockwise hysteretic relationships between the stream discharge and its isotope concentration were identified. Results were confronted with the previously published concepts of the runoff formation at the catchments under study. The research was funded by the Czech Science Foundation, project No. 14-15201J.

  11. Phosphorus and dissolved organic carbon export during peak flow periods in three small homogenous catchments in eastern Germany

    NASA Astrophysics Data System (ADS)

    Benning, R.; Schwärzel, K.; Feger, K. H.

    2012-04-01

    Regional climate change scenarios for Central Europe predict both an overall increase in temperature and alterations in annual precipitation regimes. For large parts of Central Europe, climate change is expected to result in an increase in winter precipitation and a decrease in summer precipitation. In addition, an increase in extreme conditions, such as heat waves, prolonged drought periods, and heavy rainfall events are predicted. This research examines the potential impacts of increased heavy rainfall events on matter export from small catchment areas, and how different vegetation cover and land management options effects these exports. In order to evaluate the export of matter from different land-use types in the Eastern Ore Mountains (Saxony, NE Germany, 50° 48'18.06" North, 13° 36'24.54" East), study sites were established in three small catchments with homogeneous land-use. These study areas are each sub-catchments of the Ammelsdorf catchment, which provides inflow to the Lehnmühle reservoir (a major water supply for the city of Dresden). Each sub catchment represents one of the three main land-use types in the catchment area of the reservoir: crops (winter oilseed rape, winter wheat), grasslands, and forests (primarily spruce). Since November 2009 the discharge from these sub catchments has been continuously measured and water quality was analyzed on a weekly basis. During peak flow events, discharge was collected using automatic water samplers, which allowed for high temporal resolution analysis of matter export during these periods to be made. During the 2010 and 2011 hydrological years, several heavy rainfall events occurred which have been evaluated. During a 110-hour long precipitation event (P = 170 mm) between 37 and 81 water samples per sub catchment were collected and analyzed. The resulting export of dissolved phosphorus (ortho-PO4-) and dissolved organic carbon (DOC) from the sub catchments during this event is provided in the results. In

  12. Topic: Catchment system dynamics: Processes and feedbacks

    NASA Astrophysics Data System (ADS)

    Keesstra, Saskia

    2015-04-01

    In this meeting we can talk about my main expertise: the focus of my research ocus revolves around understanding catchment system dynamics in a holistic way by incorporating both processes on hillslopes as well as in the river channel. Process knowledge enables explanation of the impact of natural and human drivers on the catchment systems and which consequences these drivers have for water and sediment connectivity. Improved understanding of the catchment sediment and water dynamics will empower sustainable land and river management and mitigate soil threats like erosion and off-side water and sediment accumulation with the help of nature's forces. To be able to understand the system dynamics of a catchment, you need to study the catchment system in a holistic way. In many studies only the hillslopes or even plots are studied; or only the channel. However, these systems are connected and should be evaluated together. When studying a catchment system any intervention to the system will create both on- as well as off sites effects, which should especially be taken into account when transferring science into policy regulations or management decisions.

  13. IPY to Mark Expansion of Research Facilities on the North Slope of Alaska

    NASA Astrophysics Data System (ADS)

    Zak, B. D.; Eicken, H.; Sheehan, G. W.; Glenn, R.

    2004-12-01

    The Barrow Global Climate Change Research Facility will open to researchers on the North Slope of Alaska during the 2007-08 anniversary of the first IPY. Between 1949 and 1980, arctic researchers were very active on the North Slope and in nearby waters largely because of the Naval Arctic Research Laboratory (NARL) at Barrow. NARL provided easy access, laboratories and logistical support. NARL was closed in 1981, but particularly during this past decade, Barrow-based arctic research projects have been back on the upswing. The National Oceanic and Atmospheric Administration (NOAA) Climate Monitoring and Diagnostics Laboratory (CMDL) Barrow station was founded during the 1970s, and continues as part of NOAA's five station global network for monitoring atmospheric composition. The North Slope Borough's Department of Wildlife Management (DWM) has for the past 20 years conducted its own research. The DWM also served as logistical provider for growing numbers of arctic researchers without other logistical support. In the late 1990s, the Department of Energy Atmospheric Radiation Measurement program (ARM: DOE's principal climate change research effort) created a Cloud and Radiation Testbed on the North Slope with atmospheric instrumentation at Barrow and Atqasuk. It is now part of the ARM Climate Research Facility, a National User Facility. In response to growing researcher needs, the Barrow Arctic Science Consortium (BASC) was formed in the late 1990s as a non-profit logistical support and community coordinating organization, and received the endorsement of Ukpeagvik Inupiat Corporation (UIC), NSB and the local community college. BASC provides logistical support to National Science Foundation (NSF) researchers through a cooperative agreement, and to others on a fee for service basis. UIC also dedicated 11 square miles of its land as the Barrow Environmental Observatory (BEO), and charged BASC with management of the BEO. This land that has been used for research for more

  14. Critical uncertainties and research needs for the restoration and conservation of native lampreys in North America

    USGS Publications Warehouse

    Mesa, Matthew G.; Copeland, Elizabeth S.

    2009-01-01

    We briefly reviewed the literature, queried selected researchers, and drew upon our own experience to describe some critical uncertainties and research needs for the conservation and restoration of native lampreys in North America. We parsed the uncertainties and research needs into five general categories: (1) population status; (2) systematics; (3) passage at dams, screens, and other structures; (4) species identification in the field; and (5) geneal biology and ecology. For each topic, we describe why the subject is important for lampreys, briefly smmarize our current state of knowledge, and discuss the key data or information gaps.

  15. Transit time estimation using tritium and stable isotopes in a Mediterranean mountain catchment

    NASA Astrophysics Data System (ADS)

    Roig-Planasdemunt, Maria; Stewart, Mike; Latron, Jérôme; Llorens, Pilar; Morgenstern, Uwe

    2015-04-01

    Water resources of Mediterranean regions mainly depend on runoff generated in mountain areas. Therefore, study of the time water spends travelling through Mediterranean mountains is important for water resources management as it reflects the ability of catchments to retain and release water. Natural isotopes (tritium and stable isotopes) have been used in different environments to quantify the ages of water within catchments. However, there are relatively few studies of water transit times in Mediterranean mountain regions. Additionally, tritium dating is more common in Southern Hemisphere streams because they were less affected by tritium produced mainly in the North Hemisphere by nuclear weapons testing in the 1950s and 60s. With the aim of improving knowledge of the hydrological catchment functioning of Mediterranean mountain areas, this work estimates water transit times in spring water, groundwater and stream water using tritium and stable isotope (δ18O and δ2H) measurements in the Vallcebre Research Catchments (NE Spain, 42° 12'N, 1° 49'E). Tritium measurements from a previous study carried out in 1996-1998 (Herrmann et al., 1999) were supplemented by new samples collected on 3 November 2013. Difficulties with the age interpretation of the tritium measurements arise from the determination of the tritium input function, the different accuracies of the tritium measurements and the ambiguous ages resulting from past input of tritium from nuclear testing to the atmosphere. Water stable isotope samples were collected in rainfall, spring water, groundwater and streamwater at baseflow conditions every 15 days over a 27 month period. Detailed distributed hydrometric measurements (precipitation, potential evapotranspiration, discharge and water table level) were obtained during the same period. Preliminary results using δ18O, δ2H and tritium show that mean transit times in the Cal Rodó catchment (4.2 km2) ranged between 1.3 and 11.6 years. The lowest mean

  16. Characterizing streamflow generation in Alpine catchments

    NASA Astrophysics Data System (ADS)

    Chiogna, Gabriele; Cano Paoli, Karina; Bellin, Alberto

    2016-04-01

    Developing effective hydrological models for streamflow generation in Alpine catchments is challenging due to the inherent complexity of the intertwined processes controlling water transfer from hillslopes to streams and along the river network. With water discharge as the sole observational variable it is impossible to differentiate between different streamflow sources, and modelling activity is often limited to simplified phenomenological rainfall-runoff models. This study focuses on quantifying streamflow sources at different temporal scales and the associated uncertainty by using natural tracer data (electrical conductivity, oxygen and hydrogen stable isotopes ratios) as observational variables supplementing streamflow measurements. We determine the spatial and temporal hydrological behavior and the mean residence time of water in the Vermigliana catchment, North-Eastern Italy and we separate contributions to streamflow originating from Presena and Presanella glaciers, both exerting a strong control on the hydrologic budget of the study site. Furthermore, we identify a seasonal control on the effect of storm events. The catchment responded rapidly to precipitation events in early autumn, it was unaffected by precipitation events in early spring, while runoff generation was enhanced by snow melting in late autumn. Air temperature is identified as the main controlling parameter, in addition to precipitation. Two-component mixing analysis showed that the relative contribution of new water, which can contribute up to 75% of total streamflow, is very rapid. Only two hours time-lag was observed between the beginning of the precipitation event and the emergence of a significant contribution of new water. These results evidence the relevance of mixing between pre-event and event water in the Vermigliana catchment, and in similar high elevation Alpine catchments. This study provides new insights on the dynamics of streamflow generation in Alpine catchments and a

  17. Building International Research Partnerships in the North Atlantic-Arctic Region

    NASA Astrophysics Data System (ADS)

    Benway, Heather M.; Hofmann, Eileen; St. John, Michael

    2014-09-01

    The North Atlantic-Arctic region, which is critical to the health and socioeconomic well being of North America and Europe, is susceptible to climate-driven changes in circulation, biogeochemistry, and marine ecosystems. The need for strong investment in the study of biogeochemical and ecosystem processes and interactions with physical processes over a range of time and space scales in this region was clearly stated in the 2013 Galway Declaration, an intergovernmental statement on Atlantic Ocean cooperation (http://europa.eu/rapid/press-release_IP-13-459_en.htm). Subsequently, a workshop was held to bring together researchers from the United States, Canada, and Europe with expertise across multiple disciplines to discuss an international research initiative focused on key features, processes, and ecosystem services (e.g., Atlantic Meridional Overturning Circulation, spring bloom dynamics, fisheries, etc.) and associated sensitivities to climate changes.

  18. A history of early geologic research in the Deep River Triassic Basin, North Carolina

    USGS Publications Warehouse

    Clark, T.W.

    1998-01-01

    The Deep River Triassic basin has one of the longest recorded histories of geologic research in North Carolina. A quick perusal of nineteenth century geologic literature in North Carolina reveals the Deep River basin has received a tremendous amount of attention, second only, perhaps, to the gold deposits of the Carolina slate belt. While these early researchers' primary interests were coal deposits, many other important discoveries, observations, and hypotheses resulted from their investigations. This article highlights many of the important advances made by these early geo-explorers by trying to include information from every major geologic investigation made in the Deep River basin from 1820 to 1955. This article also provides as thorough a consolidated history as is possible to preserve the exploration history of the Deep River basin for future investigators.

  19. What makes catchment management groups "tick"?

    PubMed

    Oliver, P

    2001-01-01

    The work of catchment management groups throughout Australia represents a significant economic and social investment in natural resource management. Institutional structures and policies, the role of on-ground coordinators, facilitation processes, citizen participation and social capital are critical factors influencing the success of catchment management groups. From a participant-researcher viewpoint, this paper signposts research directions and themes that are being pursued from the participant/coordinator, catchment group, and lead government/non-government agency perspective on the influence of these factors on the success of a catchment management group in the Pumicestone Region of Southeast Queensland, Australia. Research directions, themes and discussion/reflection points for practitioners include--the importance of understanding milieu; motivation; success; having fun; "networking networks"; involvement of "nontraditional" stakeholders; development of stakeholder/participant partnerships; learning from other practitioners; methods of stakeholder/participant representation; evaluation; the need for guiding principles or philosophy; the equivalence of planning, implementation, evaluation, and resourcing; catchments as fundamental units of Nature; continuity of support for groups; recognising a new role for government; working with existing networks; and the need for an eclectic approach to natural resource management. PMID:11424936

  20. Stormflow generation: A meta-analysis of field evidence from small, forested catchments

    NASA Astrophysics Data System (ADS)

    Barthold, Frauke K.; Woods, Ross A.

    2015-05-01

    Combinations of runoff characteristics are commonly used to represent distinct conceptual models of stormflow generation. In this study, three runoff characteristics: hydrograph response, time source of runoff water, and flow path are used to classify catchments. Published data from the scientific literature are used to provide evidence from small, forested catchments. Each catchment was assigned to one of the eight conceptual models, depending on the combination of quick/slow response, old/new water, and overland/subsurface flow. A standard procedure was developed to objectively diagnose the predominant conceptual model of stormflow generation for each catchment and assess its temporal and spatial support. The literature survey yielded 42 catchments, of which 30 catchments provide a complete set of qualitative runoff characteristics resulting in one of the eight conceptual models. The majority of these catchments classify as subsurface flow path dominated. No catchments were found for conceptual models representing combinations of quick response-new water-subsurface flow (SSF), slow-new-SSF, slow-old-overland flow (OF) nor new-slow-OF. Of the 30 qualitatively classified catchments, 24 provide a complete set of quantitative measures. In summary, the field support is strong for 19 subsurface-dominated catchments and is weak for 5 surface flow path dominated catchments (six catchments had insufficient quantitative data). Two alternative explanations exist for the imbalance of field support between the two flow path classes: (1) the selection of research catchments in past field studies was mainly to explain quick hydrograph response in subsurface dominated catchments; (2) catchments with prevailing subsurface flow paths are more common in nature. We conclude that the selection of research catchments needs to cover a wider variety of environmental conditions which should lead to a broader, and more widely applicable, spectrum of resulting conceptual models and process

  1. North American deep underground laboratories: Soudan Underground Laboratory, SNOLab, and the Sanford Underground Research Facility

    NASA Astrophysics Data System (ADS)

    Lesko, Kevin T.

    2015-08-01

    Over the past several decades, fundamental physics experiments have required access to deep underground laboratories to satisfy the increasingly strict requirements for ultra-low background environments and shielding from cosmic rays. In this presentation, I summarize the existing and anticipated physics programs and laboratory facilities of North America's deep facilities: The Soudan Underground Laboratory in Minnesota, SNOLab in Ontario, Canada, and the Sanford Underground Research Facility in Lead, South Dakota.

  2. Management of North American Culicoides Biting Midges: Current Knowledge and Research Needs.

    PubMed

    Pfannenstiel, Robert S; Mullens, Bradley A; Ruder, Mark G; Zurek, Ludek; Cohnstaedt, Lee W; Nayduch, Dana

    2015-06-01

    Culicoides biting midges (Diptera: Ceratopogonidae) are biological vectors of two important viruses impacting North American ruminants--bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV). These viruses have been identified for over 60 years in North America, but we still lack an adequate understanding of the basic biology and ecology of the confirmed vector, Culicoides sonorensis, and know even less about other putative Culicoides vector species. The major gaps in our knowledge of the biology of Culicoides midges are broad and include an understanding of the ecology of juveniles, the identity of potential alternate vector species, interactions of midges with both pathogens and vertebrates, and the effectiveness of potential control measures. Due to these broad and numerous fundamental knowledge gaps, vector biologists and livestock producers are left with few options to respond to or understand outbreaks of EHD or BT in North America, or respond to emerging or exotic Culicoides-transmitted pathogens. Here we outline current knowledge of vector ecology and control tactics for North American Culicoides species, and delineate research recommendations aimed to fill knowledge gaps. PMID:26086558

  3. The Effect of Terrain Aspect on Interannual Variability of Hydrologic Response in Mountainous Catchments in New Mexico

    NASA Astrophysics Data System (ADS)

    Zapata, X.; Troch, P. A.; McIntosh, J. C.; Broxton, P. D.; Brooks, P. D.

    2012-12-01

    The aspect of the land surface in mid and high latitudes control hydrological response through differences in energy fluxes, prevailing winds, snow processes, evaporation and transpiration. In the Valles Caldera National Preserve (VCNP) in northern New Mexico, recent research has shown that north facing terrains accumulate thicker snow packs, the snow cover duration is longer, the soil moisture content is higher and hillslopes have longer water transit times. These findings suggest that catchments with a predominant north facing aspect are expected to have more water available and consequently a different hydrological response than catchments characterized by a different land orientation. This poster presents four years (2008-2011) of hydrological data in the VCNP and shows the hydrological response to interannual climate variability in mountainous catchments draining along different aspects. This investigation focuses on three perennial catchments draining Redondo Peak (3435m): La Jara (LJ; 3.67 km2), History Grove (HG; 2.42 km2) and Upper Jaramillo (UJ; 3.06 km2). The three catchments range in elevation between 2680 m and 3429 m. They share similar topographic characteristics, climate, vegetation and a complex geology. The most predominant north facing catchment is UJ; HG and LJ have both a predominant east facing aspect. This study is based on empirical observations of basin response and it has been carried out by way of monitoring physical amount, intensity and timing of water entering and leaving the catchments using the available meteorological data in the region and the instrumented network installed by the Jemez River Basin and Santa Catalina Mountains Critical Zone Observatory (http://www.czo.arizona.edu/). The climate in the region is semi-arid, continental and highly variable. For the water years (WY) 2008 and 2011 annual precipitation was 86% and 71% below the mean (P=711.5mm), and during WY 2009 and 2010, annual precipitation was 4% and 1% above the

  4. Estimating gully erosion contribution to large catchment sediment yield rate in Tanzania

    NASA Astrophysics Data System (ADS)

    Ndomba, Preksedis Marco; Mtalo, Felix; Killingtveit, Aanund

    The objective of this paper is to report on the issues and proposed approaches in estimating the contribution of gully erosion to sediment yield at large catchment. The case study is the upstream of Pangani River Basin (PRB) located in the North Eastern part of Tanzania. Little has been done by other researchers to study and/or extrapolate gully erosion results from plot or field scale to large catchment. In this study multi-temporal aerial photos at selected sampling sites were used to estimate gully size and morphology changes over time. The laboratory aerial photo interpretation results were groundtruthed. A data mining tool, Cubist, was used to develop predictive gully density stepwise regression models using aerial photos and environment variables. The delivery ratio was applied to estimate the sediment yield rate. The spatial variations of gully density were mapped under Arc View GIS Environment. Gully erosion sediment yield contribution was estimated as a ratio between gully erosion sediment yield and total sediment yield at the catchment outlet. The general observation is that gullies are localized features and not continuous spatially and mostly located on some mountains’ foot slopes. The estimated sediment yield rate from gullies erosion is 6800 t/year, which is about 1.6% of the long-term total catchment sediment yield rate. The result is comparable to other study findings in the same catchment. In order to improve the result larger scale aerial photos and high resolution spatial data on soil-textural class and saturated hydraulic conductivity - are recommended.

  5. Geoscience Research Drilling Office Operations I: the North INYO Drilling Program, 1984

    SciTech Connect

    Lysne, P.

    1986-05-01

    The North Inyo Drilling Program was part of the Continental Scientific Drilling Program/Thermal Regimes and it was put forth by the Department of Energy/Office of Basic Energy Sciences to explore roots of a 600 year old volcanic system which is found in the north-west corner of Long Valley Caldera, California. The responsibility of the Geoscience Research Drilling Office was to provide logistical support to the scientific drilling team. This support consisted of obtaining the necessary permits, obtaining a drilling contract and providing field services involving logging and core handling/laboratory facilities. The first portion of this program was successful when hole RDO-2b traversed the conduit which fed Obsidian Dome; the second portion succeeded when RDO-3a traversed the dike underlying the Inyo Chain of volcanoes.

  6. Proceedings of the North Aleutian Basin information status and research planning meeting.

    SciTech Connect

    LaGory, K. E.; Krummel, J. R.; Hayse, J. W.; Hlohowskyj, I.; Stull, E. A.; Gorenflo, L.; Environmental Science Division

    2007-10-26

    gathering of relevant literature; (2) synthesis and summary of the literature; and (3) identification and prioritization of information needs. To assist in gathering this information, MMS convened the North Aleutian Basin Information Status and Research Planning Meeting, held in Anchorage, Alaska, from November 28 through December 1, 2006; this report presents a summary of that meeting. The meeting was the primary method used to gather input from stakeholders and identify information needs and priorities for future inventory, monitoring, and research related to potential leasing and oil and gas developments in the North Aleutian Basin.

  7. Land degradation trends in upper catchments and morphological developments of braided rivers in drylands: the case of a marginal graben of the Ethiopian Rift Valley

    NASA Astrophysics Data System (ADS)

    Demissie, Biadgilgn; Frankl, Amaury; Haile, Mitiku; Nyssen, Jan

    2014-05-01

    Braided rivers have received relatively little attention in research and development activities in drylands. However, they strongly impact agroecology and agricultural activities and thereby local livelihoods. The Raya Graben (3750 km² including the escarpment) is a marginal graben of the Ethiopian Rift Valley located in North Ethiopia. In order to study the dynamics of braided rivers and the relationship with biophysical controls, 20 representative catchments were selected, ranging between 15 and 311 km². First, the 2005 morphology (length, area) of the braided rivers was related to biophysical controls (vegetation cover, catchment area and slope gradient in the steep upper catchments and gradient in the graben bottom). Second, the changes in length of the braided rivers were related to vegetation cover changes in the upper catchments since 1972. Landsat imagery was used to calculate the Normalized Difference Vegetation Index (NDVI), and to map vegetation cover and the total length of the braided rivers. Spot CNES imagery available from Google Earth was used to identify the total area of the braided rivers in 2005. A linear regression analysis revealed that the length of braided rivers was positively related to the catchment area (R²=0.32, p<0.01), but insignificantly related to vegetation cover in the upper catchments. However, there is an indication that it is an important factor in the relationship calculated for 2005 (R²=0.2, p=0.064). Similarly, the area occupied by the braided rivers was related to NDVI (R²=0.24, p<0.05) and upper catchment area (R²=0.447, p<0.01). Slope gradient is not an important explanatory factor. This is related to the fact that slope gradients are steep (average of 38.1%) in all upper and gentle (average of 3.4%) in graben bottom catchments. The vegetation cover in the upper catchments shows a statistically insignificant increasing trend (R²=0.73, p=0.067) over the last 40 years, whereas length of rivers in the graben bottom

  8. The Hydrologic Response of a Small Catchment to Clear Cutting

    NASA Astrophysics Data System (ADS)

    Abdelnour, A.; Stieglitz, M.; Pan, F.; McKane, R. B.

    2006-12-01

    We simulated how a landscape disturbance (i.e., fire or clear-cutting) alters hillslope and catchment hydrologic processes. Specifically, we simulated how the pattern and magnitude of tree removal in a catchment increases downslope transport of water and alters catchment soil moisture and discharge. The study site is the WS10 catchment of the HJ Andrews LTER, located in the Pacific NorthWest, USA. We used a spatially- explicit hydrologic model comprised of connected landscape units. We implicitly model biomass removal and the subsequent forest re-growth by manipulating evapotranspiration. We allow potential evapotranspiration to increase exponentially from zero at the onset of the disturbance to pre-disturbance values within a 40 years period. Simulations show that while soil moisture in the uplands increased in post-disturbance period, downslope flow increased only minimally. In this catchment, upland soil moisture stayed well below field capacity, and therefore, downslope lateral flow was not initiated. As such, midland and lowland soil moisture, as well as catchment discharge, remained near pre-disturbance values throughout the re-growth period. This behavior in catchment dynamics resulted primarily from the fact that seasonal temperatures and precipitations are out of phase in this region of the US.

  9. Monitoring post-fire erosion from plot- to catchment scale using a nested scale approach

    NASA Astrophysics Data System (ADS)

    Shakesby, Rick A.; Stoof, Cathelijne R.; Ferreira, Carla S. S.; P. D Walsh, Rory; Urbanek, Emilia; Ferreira, António J. D.

    2010-05-01

    Fire-induced erosion has been observed in many regions, in both wildfire and controlled fire settings. Erosion rates have in many cases been found to be scale-dependent, with erosion rates decreasing with increasing plot size. Most studies, however, have investigated fire-induced erosion at plot and hillslope scales, leaving the catchment scale largely ignored. Moreover, many studies lack pre-fire control data. Here, we present a unique study that combines the multi-scale approach of previous wildfire research with the experimental advantages of controlled fire studies. This study focuses on the 9-ha Valtorto catchment in north-central Portugal, monitored for 1.5 year and then burned by experimental fire in February 2009. During the fire, above- and belowground temperatures were monitored. Rainfall, interception, runoff and soil water repellency were monitored throughout the study period, and soils were characterized. In addition, vegetation regeneration and soil surface evolution were monitored using repeat-picture plots. Runoff and erosion were monitored by various methodologies from the small plot to the catchment scale in the years before and after the fire. At the small plot scale, sediment and organic matter losses were determined from rainfall simulations performed under dry and wet antecedent conditions. At the hillslope scale, sediment losses were determined using sediment fences with known contributing areas. Sediment trapped behind these fences was collected after major rainfall events. At the catchment scale, bedload and suspended sediment sampled in a flume installed at the catchment outlet indicated the character of sediment and nutrient losses. Post-fire runoff and erosion were compared with a 1 to 10-year pre-fire record, and with values determined from a nearby comparable unburned catchment that was used as a control. The nested-scale approach adopted in this study facilitates assessment of the effect of scale on runoff and erosion, while the use

  10. Magnitudes and Sources of Catchment Sediment: When A + B Doesn't Equal C

    NASA Astrophysics Data System (ADS)

    Simon, A.

    2015-12-01

    The export of land-based sediments to receiving waters can cause degradation of water quality and habitat, loss of reservoir capacity and damage to reef ecosystems. Predictions of sources and magnitudes generally come from simulations using catchment models that focus on overland flow processes at the expense of gully and channel processes. This is not appropriate for many catchments where recent research has shown that the dominant erosion sources have shifted from the uplands and fields following European Settlement, to the alluvial valleys today. Still, catchment models which fail to adequately address channel and bank processes are still the overwhelming choice by resource agencies to help manage sediment export. These models often utilize measured values of sediment load at the river mouth to "calibrate" the magnitude of loads emanating from uplands and fields. The difference between the sediment load at the mouth and the simulated upland loading is then proportioned to channel sources.Bank erosion from the Burnett River (a "Reef Catchment" in eastern Queensland) was quantified by comparisons of bank-top locations and by numerical modeling using BSTEM. Results show that bank-derived sediment contributes between 44 and 73% of the sediment load being exported to the Coral Sea. In comparison reported results from a catchment model showed bank contributions of 8%. In absolute terms, this is an increase in the reported average, annual rate of bank erosion from 0.175 Mt/y to 2.0 Mt/y.In the Hoteo River, New Zealand, a rural North Island catchment characterized by resistant cohesive sediments, bank erosion was found to contribute at least 48% of the total specific yield of sediment. Combining the bank-derived, fine-grained loads from some of the major tributaries gives a total, average annual loading rate for fine material of about 10,900 t/y for the studied reaches in the Hoteo River System. If the study was extended to include the lower reaches of the main stem

  11. Vegetation and topography effects on snowcover energetics in mountain catchments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mountainous regions in Western North America are snow-dominated with little or no summer precipitation. Wind and topographic structure control snow deposition, causing tremendous spatial heterogeneity in the distribution of the snowcover and the delivery of melt water across mountain catchments. Th...

  12. How old is upland catchment water?

    NASA Astrophysics Data System (ADS)

    Hofmann, Harald; Cartwright, Ian; Morgenstern, Uwe; Gilfedder, Benjamin

    2014-05-01

    Understanding the dynamics of water supply catchments is an essential part of water management. Upland catchments provide a continuous, reliable source of high quality water not only for some of the world's biggest cities, but also for agriculture and industry. Headwater streams control river flow in lowland agricultural basins as the majority of river discharge emerges from upland catchments. Many rivers are perennial and flow throughout the year, even during droughts. However, it is still unclear how reliable and continuous upland catchment water resources really are. Despite many efforts in upland catchment research, there is still little known about where the water is stored and how long it takes to travel through upper catchments. Resolving these questions is crucial to ensure that this resource is protected from changing land use and to estimate potential impacts from a changing climate. Previous research in this important area has been limited by existing measurement techniques. Knowledge to date has relied heavily on the use of variation in stable isotope signals to estimate the age and origin of water from upland catchments. The problem with relying on these measures is that as the water residence time increases, the variation in the stable isotope signal decreases. After a maximum period of four years, no variation can be detected This means that to date, the residence time in upland catchments is likely to have been vastly underestimated. Consequently, the proportion of water flow out of upland river catchments to the total river flow is also underestimated. Tritium (3H) combines directly with water molecules and enters the flow paths with the infiltrating water. Its half-life (12.32 years) makes it ideal to describe residence times in upper catchment reservoirs as it can theoretically measure water up to about 150 years old. The bomb pulse peak in the southern hemisphere was several orders of magnitude lower than in the northern hemisphere. Hence the

  13. Institutional Research: New Challenges to an Evolving Role. Proceedings of the North East Association for Institutional Research Annual Conference (13th, Philadelphia, Pennsylvania, October 26-28, 1986).

    ERIC Educational Resources Information Center

    Baylis, Bayard, Comp.

    New challenges facing the institutional research profession are covered in these 1986 conference proceedings of the North East Association for Institutional Research. Paper titles and authors include: "Institutional Research at Mercer County Community College: The Changing Role in the Eighties" (F. L. Edwards); "Course Placement and Academic…

  14. Coastal Ocean Research and Monitoring Program at the University of North Carolina at Wilmington

    NASA Astrophysics Data System (ADS)

    Bingham, F. M.; Moss, M. K.; Wilbur, A.; Posey, M.; Pietrafesa, L.; Mallin, M.; Leonard, L.; Lankford, T.; Grindlay, N.; Cooper, W.; Cahoon, L.; Durako, M.; Xie, L.; Alphin, T.

    2002-12-01

    The Coastal Ocean Research and Monitoring Program (CORMP) is a research program and observing system in the coastal ocean off the Carolinas. The program is funded by NOAA to provide an inter-disciplinary science-based framework that supports sound public policy, wise coastal use, sustainable fisheries and improved coastal ocean ecosystem health.\\Core variables of CORMP's monitoring efforts include: physical processes (meteorological and oceanographic), ocean color, water quality (e.g., nutrients, turbidity), irradiation, sediment types, benthic ecology and larval fish distribution. The program's observing system consists of monthly coordinated (multi-disciplinary) surface-based and underwater sampling transects, and a series of long-term moorings in Onslow Bay and Long Bay off North and South Carolina.

  15. Tracer-based assessment of flow paths, storage and runoff generation in northern catchments

    NASA Astrophysics Data System (ADS)

    Tetzlaff, Doerthe; Buttle, Jim; Carey, Sean K.; McGuire, Kevin; Laudon, Hjalmar; Soulsby, Chris

    2015-04-01

    We examine how tracer studies have enhanced our understanding of flow paths, residence times and sources of stream flow in northern catchments. We define northern catchments as non-glacial sites in the temperate conifer/boreal/permafrost zone, focussing mainly on sites in North America and Europe. Improved empirical and theoretical understanding of hydrological functioning has advanced the analytical tools available for tracer-based hydrograph separations, derivation of transit time distributions and tracer-aided rainfall-runoff models that are better able to link hydrological response to storage changes. However, the lack of comprehensive tracer data sets still hinders development of a generalized understanding of how northern catchments will respond to change. This paucity of empirical data leads to many outstanding research needs, particularly in rapidly changing areas that are already responding to climatic warming and economic development. To continually improve our understanding of hydrological processes in these regions our knowledge needs to be advanced using a range of techniques and approaches. Recent technological developments for improved monitoring, distributed hydrological sensor systems, more economic analysis of large sample numbers in conjunction with novel, tracer-aided modelling approaches and the use of remote sensing have the potential to help understanding of northern hydrological systems as well as inform policy at a time of rapid environmental change.

  16. Influence of vegetation on water isotope partitioning across different northern headwater catchments

    NASA Astrophysics Data System (ADS)

    Gabor, R. S.; Tetzlaff, D.; Buttle, J. M.; Carey, S. K.; Laudon, H.; Mitchell, C. P. J.; McNamara, J. P.; Soulsby, C.

    2014-12-01

    The hydrology of high latitude catchments is sensitive to small changes in temperature, and likely to be impacted by changes in climate. Vegetation water usage can play a large role in catchment hydrologic pathways, affecting how water is stored, released, and partitioned within a landscape. Thus a better understanding of how vegetation impacts water partitioning in northern catchments can help us understand how climate change will impact high-latitude hydrology. As part of the VeWa project, five catchments were chosen between 44oN and 64oN in Europe and North America, to compare the role of vegetation in the movement of water across northern landscapes. These catchments vary in aspect as well as extent of snowpack and their vegetative landscapes include heather moorland, coniferous and deciduous forests, mixed grass, and tundra landscapes. Importantly, all the catchments have records of stable isotopes in different waters of the system. An initial comparison of the water isotopes in these catchments demonstrates variation between the catchments, with the lower latitude sites showing more fractionation suggestive of evapotranspiration. While all catchments show a depletion of heavy isotopes in the spring, the depletion is most evident in catchments with a heavier snowpack. The vegetative growing season during the summer months shows the greatest impact of evapotranspiration on isotopes, indicating that an increased summer in a warmer climate would likely alter water partitioning and storage dynamics in these regions.

  17. Catchment classification and model parameter transfer with a view to regionalisation

    NASA Astrophysics Data System (ADS)

    Ley, Rita; Hellebrand, Hugo; Casper, Markus C.

    2013-04-01

    Physiographic and climatic catchment characteristics are responsible for catchment response behaviour, whereas hydrological model parameters describe catchment properties in such a way to transform input data (here: precipitation, evaporation) to runoff, hence describing the response behaviour of a catchment. In this respect, model parameters can thus be seen as catchment descriptors. A third catchment descriptor is runoff behaviour, depicted by indices derived from event runoff coefficients and Flow Duration Curves. In an ongoing research project founded by the Deutsche Forschungsgemeinschaft (DFG), we investigate the interdependencies of these three catchment descriptors for catchment classification with a view to regionalisation. The study area comprises about 80 meso-scale catchments in western Germany. These catchments are classified by Self Organising Maps (SOM) based on a) runoff behaviour and b) physical and climatic properties. The two classifications show an overlap of about 80% for all catchments and indicate a direct connection between the two descriptors for a majority of the catchments. Next, all catchments are calibrated with a simple and parsimonious conceptual model, stemming from the Superflex model framework. In this study we test the interdependencies between the classification and the calibrated model parameters by parameter transfer within and between the classes established by SOM. The model simulates total discharge, given observed precipitation and pre-estimated potential evaporation. Simulations with a few catchments show encouraging results: all simulations with the calibrated model show a good fit, which is indicated by Nash Sutcliff coefficients of about 0.8. Most of the simulations of runoff time series for catchments with parameter sets belonging to their own class display good performances too, while simulated runoff with model parameter sets from other classes display significant lower performance. This indicates that there is a

  18. The influence of naturally-occurring organic acids on model estimates of lakewater acidification using the model of acidification of groundwater in catchments (MAGIC). Summary of research conducted during year 1

    SciTech Connect

    Sullivan, T.J.; Eilers, J.M.; Cosby, B.J.; Driscoll, C.T.; Hemond, H.F.; Charles, D.F.; Norton, S.A.

    1993-03-05

    A project for the US Department of Energy, entitled ``Incorporation of an organic acid representation into MAGIC (Model of Acidification of Groundwater in Catchments) and Testing of the Revised Model UsingIndependent Data Sources`` was initiated by E&S Environmental Chemistry, Inc. in March, 1992. Major components of the project include: improving the MAGIC model by incorporating a rigorous organic acid representation, based on empirical data and geochemical considerations, and testing the revised model using data from paleolimnological hindcasts of preindustrial chemistry for 33 Adirondack Mountain lakes, and the results of whole-catchment artificial acidification projects in Maine and Norway. The ongoing research in this project involves development of an organic acid representation to be incorporated into the MAGIC modeland testing of the improved model using three independent data sources. The research during Year 1 has included conducting two workshops to agree on an approach for the organic acid modeling, developing the organic subroutine and incorporating it into MAGIC (Task 1), conducing MAGIC hindcasts for Adirondack lakes and comparing the results with paleolimnological reconstructions (Task 2), and conducting site visits to the manipulation project sites in Maine and Norway. The purpose of this report is to provide a summary of the work that has been conducted on this project during Year 1. Tasks 1 and 2 have now been completed.

  19. Spatial-temporal rainfall input resolution requirements for urban drainage modelling: a multi-storm, multi-catchment investigation

    NASA Astrophysics Data System (ADS)

    Ochoa-Rodriguez, Susana; Wang, Li-Pen; Gires, Auguste; Pina, Rui; Reinoso-Rondinel, Ricardo; Bruni, Guendalina; Ichiba, Abdellah; Gaitan, Santiago; Cristiano, Elena; van Assel, Johan; Kroll, Stefan; Murlà-Tuyls, Damian; Schertzer, Daniel; Tchiguirinskaia, Ioulia; Willems, Patrick; Onof, Christian; ten Veldhuis, Marie-Claire

    2015-04-01

    Urban hydrological applications require high resolution precipitation and catchment information in order to well represent the spatial variability, fast runoff processes and short response times of urban catchments. Although fast progress has been made over the last few decades in high resolution measurement of rainfall at urban scales, including increasing use of weather radars, the resolution of the currently available rainfall estimates (typically 1 x 1 km2 in space and 5 min in time) may still be too coarse to meet the stringent spatial-temporal scales characteristic of urban catchments. In addition, current evidence is still insufficient to provide a concrete answer regarding rainfall input resolution requirements of urban hydrological applications. With the aim of providing further evidence in this regard, in the framework of the EU Interreg RainGain project a collaborative study was conducted which investigated the impact of rainfall estimates for a range of spatial and temporal resolution combinations on the outputs of operational semi distributed models of seven urban catchments in North-West Europe. Nine storm events measured by a dual polarimetric X-band weather radar, located in the Cabauw Experimental Site for Atmospheric Research (CESAR) of the Netherlands, were selected for analysis. Based on the original radar estimates, at 100 m and 1 min resolutions, 15 different combinations of coarser spatial and temporal resolutions, up to 3000 m and 10 min, were generated. These estimates were applied to the hydraulic models of the urban catchments, all of which have similar size (between 3 and 8 km2), but different morphological, hydrological and hydraulic characteristics. When doing so, methodologies for standardising model outputs and making results comparable were implemented. Results were analysed in the light of storm and catchment characteristics. Three main features were observed in the results: (1) the impact of rainfall input resolution decreases as

  20. Picturing and modelling catchments by representative hillslopes

    NASA Astrophysics Data System (ADS)

    Loritz, Ralf; Hassler, Sibylle; Jackisch, Conrad; Zehe, Erwin

    2016-04-01

    Hydrological modelling studies often start with a qualitative sketch of the hydrological processes of a catchment. These so-called perceptual models are often pictured as hillslopes and are generalizations displaying only the dominant and relevant processes of a catchment or hillslope. The problem with these models is that they are prone to become too much predetermined by the designer's background and experience. Moreover it is difficult to know if that picture is correct and contains enough complexity to represent the system under study. Nevertheless, because of their qualitative form, perceptual models are easy to understand and can be an excellent tool for multidisciplinary exchange between researchers with different backgrounds, helping to identify the dominant structures and processes in a catchment. In our study we explore whether a perceptual model built upon an intensive field campaign may serve as a blueprint for setting up representative hillslopes in a hydrological model to reproduce the functioning of two distinctly different catchments. We use a physically-based 2D hillslope model which has proven capable to be driven by measured soil-hydrological parameters. A key asset of our approach is that the model structure itself remains a picture of the perceptual model, which is benchmarked against a) geo-physical images of the subsurface and b) observed dynamics of discharge, distributed state variables and fluxes (soil moisture, matric potential and sap flow). Within this approach we are able to set up two behavioral model structures which allow the simulation of the most important hydrological fluxes and state variables in good accordance with available observations within the 19.4 km2 large Colpach catchment and the 4.5 km2 large Wollefsbach catchment in Luxembourg without the necessity of calibration. This corroborates, contrary to the widespread opinion, that a) lower mesoscale catchments may be modelled by representative hillslopes and b) physically

  1. A detailed study on Catchment delineation for Urban areas

    NASA Astrophysics Data System (ADS)

    Sharma, B.; B M, A.; Lohani, B.; Jain, A.

    2015-12-01

    Urban flood modelling is carried out for predicting, analysing and planning of floods in urban areas. Catchment information is an important input for urban flood modelling. Automatic catchment delineation at gully gratings for urban areas using appropriate software packages/methods along with an appropriate set of input data and parameters is still a research challenge. Considering the above, the aim of this study is to (i) identify the best suitable software for automatic catchment delineation by considering gully grating as outlet (ii) understand the effect of resolution of DEM on catchments delineated (iii) understand whether to consider DEM or DSM for catchment delineation (iv) study the effect of grid based and TIN based DEM. In this study catchment delineation has been investigated considering IIT Kanpur as a study site. LiDAR data are used to generate DEM/DSM of the study area. A comparative study of catchment delineation has been carried out between ArcHydro 10.1, BASINS 4.1, ArcSWAT, WMS 7.1, and HEC-GeoHMS approaches. Catchments have been delineated for different drainage threshold areas using gully grating points as outlets and their effects have been compared for the aforementioned software. In order to understand the effect of resolution of data, DEMs of 1m and 5m resolution have been generated and compared against each other. Effects of building ridge lines and their contribution to catchment delineation has been studied by generating a DSM of 1m resolution, and comparing the results with catchments delineated using 1m DEM. In order to assess the effects of the types of DEM over catchment delineation, a grid based DEM and TIN based DEM are compared against each other using WMS 7.1 software. The results for the catchment delineation using various software illustrate that ArcHydro 10.1 performs better than any other aforementioned software. Also, it is noted that varied drainage threshold area parameters, resolutions of DEM, selection of DEM

  2. Catchment Systems Engineering: A New Paradigm in Water Management

    NASA Astrophysics Data System (ADS)

    Quinn, P. F.; Wilkinson, M. E.; Burke, S.; O'Donnell, G. M.; Jonczyk, J.; Barber, N.; Nicholson, A.

    2012-04-01

    within a catchment to take responsibility for the water quantity and quality that arises from the catchment. Further, any holistic solution requires a bottom up, problem solving agenda which is facilitated by policy makers and is underpinned by scientific knowledge. http:\\research.ncl.ac.ukproactive

  3. A methodological comparison of catchment storages in mountainous catchments

    NASA Astrophysics Data System (ADS)

    Weiler, Markus; Staudinger, Maria; Stölzle, Michael; Seeger, Stefan; Seibert, Jan; Stahl, Kerstin

    2015-04-01

    One of the most important functions of catchments is the temporary storage of water, which directly influences runoff dynamics, rainfall-runoff transformation, partitioning of evaporation and runoff fluxes, and accessibility of water to plants. Generally, a large catchment storage is considered beneficial and in particular increases the transit times and hence the buffer functioning related to water quality. Many different methods have been developed to assess catchment storage, however, there are hardly any direct comparisons of several of these methods. One challenge is the definition of water storage, while some methods allow estimation of the entire water storage in a catchment, other methods quantify only the dynamic storage. In addition, most studies focused more on lowland catchments with rain-dominated runoff regimes and observed groundwater fluctuations. Furthermore, these studies often focus on one or two catchments, but do not consider the influence of different climates on the relevance of water storage in the catchment. We applied a range of different methods to assess catchment storage characteristics in 18 catchments in the Swiss Alps, ranging from 500 to 2000m of mean elevation and hence from rainfall- to snowmelt dominated runoff regimes. The first method use only discharge information during recession periods and with varying approaches to extract discharge and storage changes between high flow and low flow, the dynamic catchment storage can be derived. In the next methods the conceptual hydrological model HBV is calibrated to the runoff dynamics and the dynamic and total catchment storages of the different compartments are being evaluated. The last methods are based on stable water isotope data analysis. We use the model TRANSEP to derive the dynamic storage as well as the total water storage of the catchment based on the transit times using several years of fortnightly isotope data in streamflow. The results show that the derived catchment

  4. Catchment controls on solute export

    NASA Astrophysics Data System (ADS)

    Musolff, Andreas; Schmidt, Christian; Selle, Benny; Fleckenstein, Jan H.

    2015-12-01

    Dynamics of solute export from catchments can be classified in terms of chemostatic and chemodynamic export regimes by an analysis of concentration-discharge relationships. Previous studies hypothesized that distinct export regimes emerge from the presence of solute mass stores within the catchment and their connectivity to the stream. However, so far a direct link of solute export to identifiable catchment characteristics is missing. Here we investigate long-term time series of stream water quality and quantity of nine neighboring catchments in Central Germany ranging from relatively pristine mountain catchments to agriculturally dominated lowland catchments, spanning large gradients in land use, geology, and climatic conditions. Given the strong collinearity of catchment characteristics we used partial least square regression analysis to quantify the predictive power of these characteristics for median concentrations and the metrics of export regime. We can show that median concentrations and metrics of the export regimes of major ions and nutrients can indeed be inferred from catchment characteristics. Strongest predictors for median concentrations were the share of arable land, discharge per area, runoff coefficient and available water capacity in the root zone of the catchments. The available water capacity in the root zone, the share of arable land being artificially drained and the topographic gradient were found to be the most relevant predictors for the metrics of export regime. These catchment characteristics can represent the size of solute mass store such as the fraction of arable land being a measure for the store of nitrate. On the other hand, catchment characteristics can be a measure for the connectivity of these solute stores to the stream such as the fraction of tile drained land in the catchments. This study demonstrates the potential of data-driven, top down analyses using simple metrics to classify and better understand dominant controls of

  5. A Research Study on the Projected Impact of the North American Free Trade Agreement (NAFTA) on Texas Public Schools.

    ERIC Educational Resources Information Center

    Cortez, Albert; And Others

    This report estimates the number of recent immigrant students that would enroll in Texas public schools as a result of the North American Free Trade Agreement (NAFTA), and recommends educational strategies to address the unique needs of recent immigrants. Research approaches included a review of existing research on immigration trends and…

  6. Studies in Teaching 1999 Research Digest. Research Projects Presented at Annual Research Forum (Winston-Salem, North Carolina, December 1999).

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    This publication presents a collection of research projects presented at the Annual Research Forum at Wake Forest University: "The Use of Group Work as an Effective Teaching Technique in Lower Level Spanish Classes" (James Blackburn); "What Are the Real Factors behind Student Motivation?" (Matthew Grey Burdick); "Can Students Communicate…

  7. North American Prodrome Longitudinal Study: a collaborative multisite approach to prodromal schizophrenia research.

    PubMed

    Addington, Jean; Cadenhead, Kristin S; Cannon, Tyrone D; Cornblatt, Barbara; McGlashan, Thomas H; Perkins, Diana O; Seidman, Larry J; Tsuang, Ming; Walker, Elaine F; Woods, Scott W; Heinssen, Robert

    2007-05-01

    This article presents the rationale, design, and preliminary findings of the North American Prodrome Longitudinal Study (NAPLS), a collaborative, multisite investigation into the earliest phase of psychotic illness. We describe how 8 independently conceived research projects were integrated methodologically, how diagnostic reliability was achieved across sites on the Structured Interview for Prodromal Syndromes, and how baseline and follow-up data were aggregated for 888 at risk and comparison subjects. Data are presented describing the demographic, academic/work, and diagnostic characteristics of 3 relevant subgroups: persons at heightened clinical risk for psychosis, help-seeking comparison subjects, and nonpsychiatric controls. The NAPLS data set will be used to explore a series of questions related to prodromal psychosis, including the descriptive phenomenology of currently accepted diagnostic criteria, conversion rates over a 30-month period, predictors of psychosis onset and functional disability, and the impact of early treatment on the course of prodromal symptoms. PMID:17255119

  8. Making Organisms Model Human Behavior: Situated Models in North-American Alcohol Research, 1950-onwards

    PubMed Central

    Leonelli, Sabina; Ankeny, Rachel A.; Nelson, Nicole C.; Ramsden, Edmund

    2014-01-01

    Argument We examine the criteria used to validate the use of nonhuman organisms in North-American alcohol addiction research from the 1950s to the present day. We argue that this field, where the similarities between behaviors in humans and non-humans are particularly difficult to assess, has addressed questions of model validity by transforming the situatedness of non-human organisms into an experimental tool. We demonstrate that model validity does not hinge on the standardization of one type of organism in isolation, as often the case with genetic model organisms. Rather, organisms are viewed as necessarily situated: they cannot be understood as a model for human behavior in isolation from their environmental conditions. Hence the environment itself is standardized as part of the modeling process; and model validity is assessed with reference to the environmental conditions under which organisms are studied. PMID:25233743

  9. Evolving the linkages between North American Monsoon Experiment research and services in the binational monsoon region

    NASA Astrophysics Data System (ADS)

    Ray, A. J.

    2007-05-01

    Multi-year drought, high interannual precipitation variability, and rapid population growth present major challenges to water resources and land managers in the U.S. Southwest and binational monsoon region. The NAME strategy to improve warm season precipitation forecasts is paying off in the understanding of the system and its potential predictability, illustrated by a special issue of the Journal of Climate with about 25 articles and numerous other published papers (e.g. Higgins and Gochis et al. 2006; Gutzler et al. 2004, Higgins et al. 2003). NOAA now has set a goal to NAME and other initiatives also have the potential to provide key insights, such as historic information regarding onset and overall strength of the monsoon as it affects stakeholder interests in flooding, soil moisture, vegetation health, and summer water demand. However, the usual avenues for scientific output, such as peer-reviewed publications and web sites designed for use by climate and weather experts, do not adequately support the flow of knowledge to operational decisionmakers. A recent workshop on Monsoon Region climate Applications in Guaymas, Sonora identified several areas in which monsoon science might contribute to reducing societal vulnerability, as well as some research findings that are suited to transition into model development and operations at service providers including NOAA and SMN. They recommended that products are needed that interpret climate forecasts for water resource management applications, and developing new regionally-tailored climate information products. This presentation will discuss how to enhance the flow of monsoon information and predictions to stakeholders by linking user-oriented perspectives with research results from NAME and other programs, including a new effort for a North American Monsoon Forecast Forum which plans to develop periodic consolidated North American Monsoon outlooks.

  10. Exploring Research Contributions of the North American Carbon Program using Google Earth and Google Map

    NASA Astrophysics Data System (ADS)

    Griffith, P. C.; Wilcox, L. E.; Morrell, A.

    2009-12-01

    The central objective of the North American Carbon Program (NACP), a core element of the US Global Change Research Program, is to quantify the sources and sinks of carbon dioxide, carbon monoxide, and methane in North America and adjacent ocean regions. The NACP consists of a wide range of investigators at universities and federal research centers. Although many of these investigators have worked together in the past, many have had few prior interactions and may not know of similar work within knowledge domains, much less across the diversity of environments and scientific approaches in the Program. Coordinating interactions and sharing data are major challenges in conducting NACP. The Google Earth and Google Map Collections on the NACP website (www.nacarbon.org) provide a geographical view of the research products contributed by each core and affiliated NACP project. Other relevant data sources (e.g. AERONET, LVIS) can also be browsed in spatial context with NACP contributions. Each contribution links to project-oriented metadata, or “project profiles”, that provide a greater understanding of the scientific and social context of each dataset and are an important means of communicating within the NACP and to the larger carbon cycle science community. Project profiles store information such as a project's title, leaders, participants, an abstract, keywords, funding agencies, associated intensive campaigns, expected data products, data needs, publications, and URLs to associated data centers, datasets, and metadata. Data products are research contributions that include biometric inventories, flux tower estimates, remote sensing land cover products, tools, services, and model inputs / outputs. Project leaders have been asked to identify these contributions to the site level whenever possible, either through simple latitude/longitude pair, or by uploading a KML, KMZ, or shape file. Project leaders may select custom icons to graphically categorize their

  11. Towards Creating an Inclusive Community of Researchers: The First Three Years of the North American Association for Environmental Education Research Symposium

    ERIC Educational Resources Information Center

    Meyers, Ronald B.; Brody, Michael; Dillon, Justin; Hart, Paul; Krasny, Marianne; Monroe, Martha; Russell, Constance; Wals, Arjen

    2007-01-01

    This article uses a series of interlinked, personal vignettes to discuss the first three years of the North American Association for Environmental Education research symposium, from the perspectives of the key organizers. Seven challenges in the field of environmental education research are identified in a recent historical context, and we…

  12. Runoff Variability in Field-scale Catchments and the Implications for Rainffall-Runoff Modeling

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Shuster, W.

    2004-12-01

    In this study long-term rainfall runoff records for two agricultural catchments (ca. 0.5 ha) in the USDA - Agricultural Research Service North Appalachian Experimental Watershed (Coshocton, OH) network were used to address the inter-event and inter-catchment variability of field-scale runoff processes. Through analyses of flood frequency and flow duration, the adjacent fallowed watersheds (WS106 and WS121) were found to be similar in terms of annual flood peaks, but less so in terms of the distribution of their discharge rates. Further investigation was focused on event-scale variations of runoff response and whether these variations can be effectively captured by rainfall-runoff models, which included: a) TR-20 (a lumped model); b) EPA-SWMM (a semi-distributed model); and c) GSSHA (a grid-based, fully distributed model). Each model was used to simulate 41 selected runoff episodes recorded in each of the two catchments, and subsequently calibrated to yield parameter values that maximize the correlation between the simulated and observed runoff peaks. Our results indicate that, despite calibration, the hydrographs derived from all models deviated considerably from actual observations, and on the basis of inter-event fluctuations, which furthermore lacked a conspicuous dependence on the magnitude of runoff peaks. Our findings suggest that, in the absence of information on rainfall distribution and soil moisture, distributed models may not be superior to lumped ones in forecasting runoff responses of field scale catchments; and the correspondence between runoff mechanisms and model representations needs to be better understood and accounted for in order to limit the uncertainties of model predictions.

  13. Catchments of general practice in different countries– a literature review

    PubMed Central

    2014-01-01

    The purpose of this paper is to review the current research on catchment areas of private general practices in different developed countries because healthcare reform, including primary health care, has featured prominently as an important political issue in a number of developed countries. The debates around health reform have had a significant health geographic focus. Conceptually, GP catchments describe the distribution, composition and profile of patients who access a general practitioner or a general practice (i.e. a site or facility comprising one or more general practitioners). Therefore, GP catchments provide important information into the geographic variation of access rates, utilisation of services and health outcomes by all of the population or different population groups in a defined area or aggregated area. This review highlights a wide range of diversity in the literature as to how GP catchments can be described, the indicators and measures used to frame the scale of catchments. Patient access to general practice health care services should be considered from a range of locational concepts, and not necessarily constrained by their place of residence. An analysis of catchment patterns of general practitioners should be considered as dynamic and multi-perspective. Geographic information systems provide opportunities to contribute valuable methodologies to study these relationships. However, researchers acknowledge that a conceptual framework for the analysis of GP catchments requires access to real world data. Recent studies have shown promising developments in the use of real world data, especially from studies in the UK. Understanding the catchment profiles of individual GP surgeries is important if governments are serious about patient choice being a key part of proposed primary health reforms. Future health planning should incorporate models of GP catchments as planning tools, at the micro level as well as the macro level, to assist policies on the

  14. Integrating the UAS in Undergraduate Teaching and Research - Opportunities and Challenges at University of North Georgia

    NASA Astrophysics Data System (ADS)

    Sharma, J. B.; Hulsey, D.

    2014-11-01

    The University of North Georgia (UNG) has begun to evaluate both fixed and rotary UAS platforms across the departments to evaluate their potential for furthering both student learning experiences and undergraduate research. A research project of the Institute for Spatial Analysis (IESA) at UNG has acquired the fixed wing eBee UAS and is currently piloting its integration into the undergraduate geospatial science curriculum. Limited very low altitude, line of sight calibration runs within areas of our campus have help us understand the capabilities that this technology brings to learning and research opportunities at UNG. In our pilot area of study on the UNG Gainesville Campus, we will collect overlapping imagery and generate 3-D models. These models will be compared with models based on LiDAR data. Geographic Object Based Image Analysis (GEOBIA) methods are essential to the analysis of voluminous high resolution UAS data and the associated computational and regulatory issues are discussed. Several future interdisciplinary projects are envisaged with the eBee UAS and this project helps establish their viability.

  15. Moments of catchment storm area

    NASA Technical Reports Server (NTRS)

    Eagleson, P. S.; Wang, Q.

    1985-01-01

    The portion of a catchment covered by a stationary rainstorm is modeled by the common area of two overlapping circles. Given that rain occurs within the catchment and conditioned by fixed storm and catchment sizes, the first two moments of the distribution of the common area are derived from purely geometrical considerations. The variance of the wetted fraction is shown to peak when the catchment size is equal to the size of the predominant storm. The conditioning on storm size is removed by assuming a probability distribution based upon the observed fractal behavior of cloud and rainstorm areas.

  16. Water Catchment and Storage Monitoring

    NASA Astrophysics Data System (ADS)

    Bruenig, Michael; Dunbabin, Matt; Moore, Darren

    2010-05-01

    Sensors and Sensor Networks technologies provide the means for comprehensive understanding of natural processes in the environment by radically increasing the availability of empirical data about the natural world. This step change is achieved through a dramatic reduction in the cost of data acquisition and many orders of magnitude increase in the spatial and temporal granularity of measurements. Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) is undertaking a strategic research program developing wireless sensor network technology for environmental monitoring. As part of this research initiative, we are engaging with government agencies to densely monitor water catchments and storages, thereby enhancing understanding of the environmental processes that affect water quality. In the Gold Coast hinterland in Queensland, Australia, we are building sensor networks to monitor restoration of rainforest within the catchment, and to monitor methane flux release and water quality in the water storages. This poster will present our ongoing work in this region of eastern Australia. The Springbrook plateau in the Gold Coast hinterland lies within a World Heritage listed area, has uniquely high rainfall, hosts a wide range of environmental gradients, and forms part of the catchment for Gold Coast's water storages. Parts of the plateau are being restored from agricultural grassland to native rainforest vegetation. Since April 2008, we have had a 10-node, multi-hop sensor network deployed there to monitor microclimate variables. This network will be expanded to 50-nodes in February 2010, and to around 200-nodes and 1000 sensors by mid-2011, spread over an area of approximately 0.8 square kilometers. The extremely dense microclimate sensing will enhance knowledge of the environmental factors that enhance or inhibit the regeneration of native rainforest. The final network will also include nodes with acoustic and image sensing capability for

  17. Downward approach at the catchment scale or at the catchment set scale?

    NASA Astrophysics Data System (ADS)

    Perrin, C.; Andréassian, V.; Le Moine, N.

    2009-04-01

    examples drawn from our past and current research activities based on large data sets. Surprisingly, the level of model complexity that could be achieved following this approach is quite low, which may indicate that the current understanding of the main features of hydrological catchment behaviour is not as good as many models may suggest (Michel et al., 2006). We hope that this communication will stimulate discussion on this issue and encourage more hydrologists to work on large sets of catchments (Andréassian et al., 2006). References: Andréassian, V., Hall, A., Chahinian, N., Schaake, J. (2006). Introduction and synthesis: Why should hydrologists work on a large number of basin data sets? IAHS Publication n° 307, 1-5. Klemes, V. (1983). Conceptualisation and scale in hydrology. Journal of Hydrology, 65, 1-23. Michel, C., Perrin, C., Andréassian, V. Oudin, L. and Mathevet, T. (2006). Has basin scale modelling advanced far beyond empiricism, IAHS Publication n° 307, 108-116. Sivakumar, B. (2008). Dominant processes concept, model simplification and classification framework in catchment hydrology, Stoch. Envrion. Res. Risk. Assess., 22, 737-748. Sivapalan, M., Blöschl, G., Zhang, L. and Vertessy, R. (2003). Downward approach to hydrological prediction. Hydrological Processes, 17, 2101-2111.

  18. Studies in Teaching 2001 Research Digest. Research Projects Presented at Annual Research Forum (Winston-Salem, North Carolina, December 2001).

    ERIC Educational Resources Information Center

    McCoy, Leah P.

    This collection of research projects includes: "What Types of Questions Do Mathematics Teachers Ask?" (Cynthia L. Adams); "Will Alternate Assessment Formats Create a Difference in Student Motivation to Study?" (Robyn J. Allen); "Factors Affecting the Motivation of Students" (Dejon J. Banks); "The Dynamics of English Classes with Gender Minorities"…

  19. Hydrological Catchment Similarity Assessment in Geum River Catchments, Korea

    NASA Astrophysics Data System (ADS)

    Ko, Ara; Park, Kisoon; Lee, Hyosang

    2013-04-01

    Similarity measure of catchments is essential for regionalization studies, which provide in depth analysis in hydrological response and flood estimations at ungauged catchments. However, this similarity measure is often biased to the selected catchments and is notclearly explained in hydrological sense. This study applied a type of hydrological similarity distance measure-Flood Estimation Handbook to 25 Geum river catchments, Korea. Three Catchment Characteristics, Area (A)-Annual precipitation (SAAR)-SCS Curve Number (CN), are used in Euclidian distance measures. Furthermore, six index of Flow Duration Curve (ILow:Q275/Q185, IDrought:Q355/Q185, IFlood:Qmax/Q185, IAbundant:Q95/Q185, IFloodDuration:Q10/Q355 and IRiverRegime:Qmax/Qmin) are applied to clustering analysis of SPSS. The catchments' grouping of hydrological similarity measures suggests three groups: H1 (Cheongseong, Gidae, Bukil, Oksan, Seockhwa, Habgang and Sangyeogyo), H2 (Cheongju, Guryong, Ugon, Boksu, Useong and Seokdong) and H3 (Muju, Yangganggyo and YongdamDam). The four catchments (Cheoncheon, Donghyang, DaecheongDam and Indong) are not grouped in this study. The clustering analysis of FDC provides four Groups; CFDC1 (Muju, YongdamDam, Yangganggyo, DaecheongDam, Cheongseong, Gidae, Seokhwa, Bukil, Habgang, Cheongju, Oksan, Yuseong and Guryong), CFDC2 (Cheoncheon, Donghyang, Boksu, Indong, Nonsan, Seokdong, Ugon, Simcheon, Useong and Sangyeogyo), CFDC3 (Songcheon) and CFDC4 (Tanbu). The six catchments (out of seven) of H1 are grouped in CFDC1, while Sangyeogyo is grouped in CFDC2. The four catchments (out of six) of H2 are also grouped in CFDC2, while Cheongju and Guryong are grouped in CFDC1. The catchments of H3 are categorized in CFDC1. The authors examine the results (H1, H2 and H3) of similarity measure based on catchment physical descriptors with results (CFDC1 and CFDC2) of clustering based on catchment hydrological response. The results of hydrological similarity measures are supported by

  20. Controls on suspended sediment, particulate and dissolved organic carbon export from two adjacent catchments with contrasting land-uses, Exmoor UK.

    NASA Astrophysics Data System (ADS)

    Glendell, M.; Brazier, R. E.

    2012-04-01

    The fluvial export of total organic carbon (particulate and dissolved) plays an important role in the transportation of organic carbon from terrestrial to aquatic ecosystems, with implications for the understanding of the global carbon cycle and calculations of regional carbon budgets. The terrestrial biosphere contains large amounts of stored carbon in the soil and vegetation, thus a small change in the terrestrial carbon pool may have significant implications for atmospheric CO2 concentrations. Since the onset of agriculture, human activities have accelerated soil erosion rates 10- to 100- fold above all estimated natural background levels, especially in the uplands and at lower latitudes, whilst increasing DOC concentrations over the past decades have been reported in rivers across Western Europe and North America, raising concerns about potential destabilisation of the terrestrial soil carbon pool. The increased input of fine sediment and organic carbon into aquatic environments is also an important factor in stream water quality, being responsible for direct ecological effects as well as transport of a range of contaminants. Many factors, such as topography, hydrological regime and vegetation are known to influence the fluvial export of carbon from catchments. However, most work to date has focused on DOC losses from either forested or peaty catchments, with only limited studies examining the controls and rates of TOC (dissolved and particulate) fluxes from agricultural catchments, particularly during flood events. This research aims to: • Quantify the fluxes of total suspended sediment, total dissolved and total particulate carbon in two adjacent catchments with contrasting land-uses and • Examine the controlling factors of total fluvial carbon fluxes in a semi-natural and agricultural catchment in order to assess the impact of agricultural land-use on fluvial carbon export. The two contrasting study catchments (the Aller and Horner), in south

  1. Priorities for ecological research on energy crops in the north central states

    SciTech Connect

    Ugoretz, S.M.; Rineer, K.C.; Downing, M.

    1995-07-26

    Following the principles set by the National Biofuels Roundtable, a workshop was held in March 1995 which brought together a group of stakeholders and experts in the field of biomass energy and ecology. The mission of the workshop was to identify and set priorities for ecological research to ensure that large-scale biomass energy development in the North Central states occurs in an ecologically sound, sustainable manner. The workshop found that questions about the landscape-scale deployment of biomass plantations were most pressing. The workshop recommended that adaptive resource management principles be applied in a phased development of increasingly larger plantations. Each phase of development would help to answer questions about landscape-scale development; improving the design of subsequent phases. Principles of sustainable agriculture should also be applied to biomass plantations to minimize impact on soils and water quality, maintain productivity and benefit the rural economy. Results of the workshop will be helpful to natural resource and research agencies, as well as utilities and biomass energy developers.

  2. The "Teflon basin" myth: Snow-soil interactions in mountain catchments in the western US

    NASA Astrophysics Data System (ADS)

    Williams, M. W.; Cowie, R. M.

    2015-12-01

    In much of western North America, snow and snowmelt provide the primary means for storage of winter precipitation, effectively transferring water from the relatively wet winter season to the typically dry summers. A common assumption is that high-elevation catchments in the western United States behave like "Teflon basins" and that water released from seasonal storage in snow packs flows directly into streams with little or no interaction with underlying soils. Here I present information from a variety of catchments in the Colorado Front Range on snowmelt/soil interactions using isotopic, geochemical, nutrient and hydrometric data in 2- and 3- component hydrograph separations, along with end-member mixing analysis (EMMA). For most catchments we measured these parameters in weekly precipitation, the seasonal snowpack, snowmelt before contact with the ground, discharge, springs, soil solution, and groundwater. We ran EMMA at the catchment scale for catchments that represent the rain-snow transition zone in the montane forest, the seasonally snow covered sub-alpine to alpine transition zone, and a high-elevation alpine zone near the continental divide. In all catchments three end-members were the source waters for about 95% of discharge. Two end-members were the same in all catchments, snow and groundwater. For the alpine catchment talus springs was the third water source, while rain was the third water source in the two lower-elevation catchments. For all three catchments, soil solution plotted with stream waters along or near a line connecting the snow and groundwater end-members. Thus, for seasonally snow-covered catchments from montane to alpine ecosystems, snowmelt infiltrates underlying soils before snowmelt recharges groundwater reservoirs and contributes to surface flows. Seasonally snow-covered catchments are not Teflon basins. Rather, snowmelt infiltrates soils where solute concentrations are changed by biological and geochemical processes.

  3. The topographic wetness index as a predictor for hot spots of DOC export from catchments

    NASA Astrophysics Data System (ADS)

    Musolff, Andreas; Oosterwoud, Marieke; Tittel, Jörg; Selle, Benny; Fleckenstein, Jan H.

    2015-04-01

    Dissolved organic carbon (DOC) concentrations in the discharge of many catchments in Europe and North America are rising. This increase is of concern for the drinking water supply from reservoirs since high DOC concentrations cause additional costs in water treatment and potentially the formation of harmful disinfection by-products. A prerequisite for understanding this increase is the knowledge on the spatial distribution of dominant soil DOC sources within catchments and on mobilization as well as transfer processes to the surface water. A number of studies identified wetland soils as the dominant source with fast mobilization and short transit times to the receiving surface water. However, most studies have either focussed on smaller, hillslope and single catchment or on larger scale multi-catchment assessments. Moreover, information on the distribution of soil types in catchments is not always readily available. This study brings together both types of assessment in a data-driven top-down approach: (i) a detailed survey on DOC concentration and loads over the course of one year within two paired data-rich catchments discharging into a large drinking water reservoir in central Germany and (ii) a database of hydrochemistry and physio-geographic characteristics of 113 catchments draining into 58 reservoirs across Germany over the course of 16 years. The objective is to define hot spots of DOC export within the catchments for both types of assessments (i, ii) and to test the suitability of the topographic wetness index (TWI) as a proxy for well-connected wetland soils at various spatial scales. In the sub-catchments of assessment (i) the spatial variability of concentrations and loads was much smaller than expected. None of the studied sub-catchments was a predominant producer of the total DOC loads exported from the catchments. We found the mean concentrations and loads to be positively correlated with the share of groundwater-dominated soils in the sub-catchments

  4. Expansion of Economic Base Analysis: Labor Availability in North-Central New Mexico. Research Report No. 264.

    ERIC Educational Resources Information Center

    Carruthers, Garrey E.; And Others

    Estimates of the number of persons willing to commute, at alternative wage rates, to job opportunities in north-central New Mexico have been based on results of basic research in the region and 1970 census data. Expressed willingness to commute and socio-economic characteristics data were accumulated from a regional survey of 643 households. The…

  5. Attitudes of North Dakota Implement Dealership Managers towards a Continuing Management Education Program. Report of the Research Study.

    ERIC Educational Resources Information Center

    Kleene, Marvin D.; Priebe, Donald W.

    Conducted as part of a Farm Management Education Research and Development Project which was examining the use of variations of the Farm Management Education Program in meeting the managerial needs of agribusinesses, the descriptive study reported here was done to determine attitudes of 359 farm implement dealership managers in North Dakota towards…

  6. Gender Gaps in North American Research Productivity: Examining Faculty Publication Rates in Mexico, Canada, and the U.S.

    ERIC Educational Resources Information Center

    Padilla-Gonzalez, Laura; Metcalfe, Amy Scott; Galaz-Fontes, Jesus F.; Fisher, Donald; Snee, Iain

    2011-01-01

    The present study addresses gender gaps in North American research productivity, which may be influenced by personal and family variables, as well as professional and work-related variables. The study was conducted as part of the "Changing Academic Profession (CAP) International Survey", conducted in 2007-08. Using articles as indicator of…

  7. GLOBAL CHANGE RESEARCH NEWS #12: U.S.-- CANADA SYMPOSIUM ON NORTH AMERICAN CLIMATE CHANGE AND WEATHER EXTREMES

    EPA Science Inventory

    This edition reports on a U.S.-Canada Symposium onNorth American Climate Change and Weather Extremes that was held in Atlanta in October. This symposium was conducted by EPA's Global Change Research Program in partnership with Environment Canada and the U.S. National Weather Se...

  8. Air-Quality Data from NARSTO (North American Research Strategy for Tropospheric Ozone)

    DOE Data Explorer

    NARSTO is a public/private partnership dedicated to improving management of air quality in North America. It was established on February 13, 1995 when representatives of Canada, the United States, and Mexico signed the NARSTO Charter in a ceremony at the White House. The Department of Energy is one of the charter members providing funding. The central programmatic goal of NARSTO is to provide data and information for use in the determination of workable, efficient, and effective strategies for local and regional ozone and fine particle management. Since its founding, NARSTO has completed three major scientific Assessments of critical air quality management issues. NARSTO maintains the Quality Systems Science Center and the NARSTO Data Archive for storing data from NARSTO Affiliated Research Activities and making these data available to the scientific community. NARSTO also facilitates activities, such as the Reactivity Research Working Group, which provide critical reviews of the state of the science in areas of interest to air quality policy makers. In January 1997, the U.S. Department of Energy's Environmental Sciences Division announced their sponsorship of the NARSTO Quality Systems Science Center (QSSC). The QSSC is located at the Oak Ridge National Laboratory within the Carbon Dioxide Information Analysis Center (CDIAC). Quality Assurance and Data Management assistance and guidelines are provided by the QSCC, along with access to data files. The permanent data archive is maintained by the NASA EOSDIS Distributed Active Archive Center at the Langley Research Center. The archived data can be reached by a link from the QSSC.(Specialized Interface) See also the NARSTO web site at http://www.narsto.org/

  9. Multiple-method approaches for quantifying fine sediment dynamics in river catchments over contemporary timescales

    NASA Astrophysics Data System (ADS)

    Smith, Hugh

    2015-04-01

    Understanding the patterns and processes of contemporary fine sediment dynamics in river catchments constitutes a key research challenge for catchment scientists. Such knowledge has considerable value for the targeting of management resources to reduce excess fine sediment supply and its impacts on water resources and aquatic ecosystems. Many past studies tended to focus on a single compartment of the fine sediment cascade and utilised a limited range of research methods. For more holistic understanding, the use of multiple-method approaches is required to provide data on the sources, transfer, storage, and transit times of fine sediment in river catchments. Such approaches would allow scientists to better conceptualise catchment processes controlling the movement of fine sediment across a range of spatial scales. It may also enhance the scientific quality of catchment-scale studies through the acquisition of multiple lines of evidence concerning a particular research problem. The specific combination of fine sediment tracing and fingerprinting procedures with catchment sediment flux measurements and sediment budget modelling has considerable potential to enhance our knowledge of contemporary sediment dynamics. This combination of techniques offers complementary information and the opportunity to compare datasets, such as estimates of catchment sediment source contributions obtained using sediment tracers with direct measurements of sediment fluxes or catchment model outputs. This contribution explores the potential for such combinations of methods to yield distinctive insights not otherwise available from the use of only one of these techniques. It draws on published examples of multiple-method studies by the author from small agricultural and wildfire-affected forest catchments (1-2 km2) in south-east Australia and from larger agricultural river catchments (38-920 km2) in south-west England. It will also identify possible directions for catchment research based

  10. Statistical Abstract of Higher Education in North Carolina, 2008-09. Research Report 01-09

    ERIC Educational Resources Information Center

    Dow, Daphne

    2009-01-01

    The University of North Carolina presents the forty-first annual "Statistical Abstract of Higher Education in North Carolina." This abstract covers the breadth of higher education activities in the State in their quantitative aspect, from simple counts of enrollment and degrees conferred to complex analyses of the flow of student transfers among…

  11. Fine-suspended sediment and water budgets for a large, seasonally dry tropical catchment: Burdekin River catchment, Queensland, Australia

    NASA Astrophysics Data System (ADS)

    Bainbridge, Zoë T.; Lewis, Stephen E.; Smithers, Scott G.; Kuhnert, Petra M.; Henderson, Brent L.; Brodie, Jon E.

    2014-11-01

    The Burdekin River catchment (˜130,400 km2) is a seasonally dry tropical catchment located in north-east Queensland, Australia. It is the single largest source of suspended sediment to the Great Barrier Reef (GBR). Fine sediments are a threat to ecosystems on the GBR where they contribute to elevated turbidity (reduced light), sedimentation stress, and potential impacts from the associated nutrients. Suspended sediment data collected over a 5 year period were used to construct a catchment-wide sediment source and transport budget. The Bowen River tributary was identified as the major source of end-of-river suspended sediment export, yielding an average of 530 t km-2 yr-1 during the study period. Sediment trapping within a large reservoir (1.86 million ML) and the preferential transport of clays and fine silts downstream of the structure were also examined. The data reveal that the highest clay and fine silt loads—which are of most interest to environmental managers of the GBR—are not always sourced from areas that yield the largest total suspended sediment load (i.e., all size fractions). Our results demonstrate the importance of incorporating particle size into catchment sediment budget studies undertaken to inform management decisions to reduce downstream turbidity and sedimentation. Our data on sediment source, reservoir influence, and subcatchment and catchment yields will improve understandings of sediment dynamics in other tropical catchments, particularly those located in seasonally wet-dry tropical savannah/semiarid climates. The influence of climatic variability (e.g., drought/wetter periods) on annual sediment loads within large seasonally dry tropical catchments is also demonstrated by our data.

  12. LLNL Middle East and North Africa and Former Soviet Union Research Database

    SciTech Connect

    O'Boyle, J.L.; Ruppert, S.D.; Hauk, T.F.; Dodge, D.; Firpo, M.

    2000-07-14

    The Lawrence Livermore National Laboratory (LLNL) Ground-Based Nuclear Explosion Monitoring (GNEM) R and D program has made significant progress populating a comprehensive Seismic Research knowledge Base (SRKB) and deriving calibration parameters for the Middle East and North Africa (ME/NA) and Former Soviet Union (FSU) regions. The LLNL SRKB provides not only a coherent framework in which to store and organize very large volumes of collected seismic waveforms, associated event parameter information, and spatial contextual data, but also provides an efficient data processing/research environment for deriving location and discrimination correction surfaces. The SRKB is a flexible and extensible framework consisting of a relational database (RDB), Geographical Information System (GIS), and associated product/data visualization and data management tools. This SRKB framework is designed to accommodate large volumes of data (over 2 million waveforms from 20,000 events) in diverse formats from many sources in addition to maintaining detailed quality control and metadata. Using the SRKB framework, they are combining travel-time observations, event characterization studies, and regional tectonic models to assemble a library of ground truth information and phenomenology correction surfaces required for support of the ME/NA and FSU regionalization program. Corrections and parameters distilled from the LLNL SRKB provide needed contributions to the DOE Knowledge Base (DOE KB) for the ME/NA and FSU regions and will help improve monitoring for underground nuclear testing. The LLNL research products will facilitate calibration of IMS stations (primary and auxiliary), their surrogates (if not yet installed) and selected gamma stations necessary to complete the above tasks in the ME/NA and FSU regions. They present expanded lookup tables for critical station parameter information (including location and response) and a new integrated and reconciled event catalog dataset including

  13. Bridges to the Future: Building Linkages for Institutional Research. North East Association for Institutional Research Annual Conference Proceedings (27th, Pittsburgh, PA, November 4-7, 2000).

    ERIC Educational Resources Information Center

    North East Association for Institutional Research.

    This document contains papers, summaries of panel presentations, and work share meetings from the annual conference of the North East Association for Institutional Research. The papers are: (1) "The Influence of Personality Traits, Pre-College Characteristics, and Co-Curricular Experiences on College Outcomes" (Karen W. Bauer); (2) "Threading the…

  14. The North Alabama Severe Thunderstorm Observations, Research, and Monitoring Network (STORMnet)

    NASA Technical Reports Server (NTRS)

    Goodman, S. J.; Blakeslee, R.; Christian, H.; Boccippio, D.; Koshak, W.; Bailey, J.; Hall, J.; Bateman, M.; McCaul, E.; Buechler, D.; Arnold, James E. (Technical Monitor)

    2002-01-01

    The Severe Thunderstorm Observations, Research, and Monitoring network (STORMnet) became operational in 2001 as a test bed to infuse new science and technologies into the severe and hazardous weather forecasting and warning process. STORMnet is collaboration among NASA scientists, National Weather Service (NWS) forecasters, emergency managers and other partners. STORMnet integrates total lightning observations from a ten-station 3-D VHF regional lightning mapping array, the National Lightning Detection Network (NLDN), real-time regional NEXRAD Doppler radar, satellite visible and infrared imagers, and a mobile atmospheric profiling system to characterize storms and their evolution. The storm characteristics and life-cycle trending are accomplished in real-time through the second generation Lightning Imaging Sensor Demonstration and Display (LISDAD II), a distributed processing system with a JAVA-based display application that allows anyone, anywhere to track individual storm histories within the Tennessee Valley region of north Alabama and Tennessee, a region of the southeastern U.S. well known for abundant severe weather.

  15. Prevalence of cattle flukes infection at Andassa Livestock Research Center in north-west of Ethiopia

    PubMed Central

    Yeneneh, Asressa; Kebede, Hassen; Fentahun, Tewodros; Chanie, Mersha

    2012-01-01

    A cross sectional study was carried out from October 2010 to March 2011 at Andassa Livestock Research Center, North-West Ethiopia. The objective was to determine the prevalence of cattle flukes infection. Faecal samples were collected from a total of 384 cattle, cross breed (n= 39) and Fogera breed (n=345) of all age groups and sex. Sedimentation technique was employed for the recovery of fluke eggs from freshly collected fecal sample. The results indicated that the overall prevalence of bovine flukes infection was 60.42%. In this study, the highest prevalence was recorded from Paramphistomosis (45.83%) followed by Fasciolosis (23.96%), and Schistosomosis (9.89%). The prevalence of flukes infection was higher in age group 1- 2 years old. There was significant difference in case of Paramphistomosis among age groups. No significant association was found between crossed breeds and sex groups for fluke’s infection. The prevalence of Paramphistomosis was high in cross breed (58.97%) than Fogera breed (44.35%). However, in both cases, there was no significant difference. The result of the present study revealed that the prevalence of major bovine fluke infection in the study area was relatively low and is the definite proof of active infection. PMID:25653752

  16. Existing data sources for clinical epidemiology: The North Denmark Bacteremia Research Database

    PubMed Central

    Schønheyder, Henrik C; Søgaard, Mette

    2010-01-01

    Bacteremia is associated with high morbidity and mortality. Improving prevention and treatment requires better knowledge of the disease and its prognosis. However, in order to study the entire spectrum of bacteremia patients, we need valid sources of information, prospective data collection, and complete follow-up. In North Denmark Region, all patients diagnosed with bacteremia have been registered in a population-based database since 1981. The information has been recorded prospectively since 1992 and the main variables are: the patient’s unique civil registration number, date of sampling the first positive blood culture, date of admission, clinical department, date of notification of growth, place of acquisition, focus of infection, microbiological species, antibiogram, and empirical antimicrobial treatment. During the time from 1981 to 2008, information on 22,556 cases of bacteremia has been recorded. The civil registration number makes it possible to link the database to other medical databases and thereby build large cohorts with detailed longitudinal data that include hospital histories since 1977, comorbidity data, and complete follow-up of survival. The database is suited for epidemiological research and, presently, approximately 60 studies have been published. Other Danish departments of clinical microbiology have recently started to record the same information and a population base of 2.3 million will be available for future studies. PMID:20865114

  17. The Annual North American Dendroecological Fieldweek: A workweek in applied tree-ring research

    SciTech Connect

    Brown, P.M.; Krusic, P.J.

    1995-12-31

    Trees record many events or processes that influence annual growth patterns. Dendrochronology is concerned with how environment and physiology affect tree growth as recorded within tree rings. The most basic principle of dendrochronology is that of crossdating, in which calendrical years are assigned to individual rings within a tree. Once crossdated, each ring is then a reflection of the climate or other environmental conditions that influenced that tree for that year. The Annual North American Dendroecological Fieldweek is a workweek in applied tree-ring research, designed to give both beginners to the discipline an introduction to its basic methodology and applications and more experienced users a change to work with and learn from others in the field in an informal group setting. The Fieldweek has had an outstanding history to date, with almost 250 participants in the five Fieldweeks from 1990 to 1994. The 6th Fieldweek is scheduled for 30 June to 8 July, 1995, at the Kananaskis Field Station in the Canadian Rockies near Calgary, Alberta.

  18. Assessing the role of urban developments on storm runoff response through multi-scale catchment experiments

    NASA Astrophysics Data System (ADS)

    Wilkinson, Mark; Owen, Gareth; Geris, Josie; Soulsby, Chris; Quinn, Paul

    2015-04-01

    Many communities across the world face the increasing challenge of balancing water quantity and quality issues with accommodating new growth and urban development. Urbanisation is typically associated with detrimental changes in water quality, sediment delivery, and effects on water storage and flow pathways (e.g. increases in flooding). In particular for mixed rural and urban catchments where the spatio-temporal variability of hydrological responses is high, there remains a key research challenge in evaluating the timing and magnitude of storage and flow pathways at multiple scales. This is of crucial importance for appropriate catchment management, for example to aid the design of Green Infrastructure (GI) to mitigate the risk of flooding, among other multiple benefits. The aim of this work was to (i) explore spatio-temporal storm runoff generation characteristics in multi-scale catchment experiments that contain rural and urban land use zones, and (ii) assess the (preliminary) impact of Sustainable Drainage (SuDs) as GI on high flow and flood characteristics. Our key research catchment, the Ouseburn in Northern England (55km2), has rural headwaters (15%) and an urban zone (45%) concentrated in the lower catchment area. There is an intermediate and increasingly expanding peri-urban zone (currently 40%), which is defined here as areas where rural and urban features coexist, alongside GIs. Such a structure is typical for most catchments with urban developments. We monitored spatial precipitation and multiscale nested (five gauges) runoff response, in addition to the storage dynamics in GIs for a period of 6 years (2007-2013). For a range of events, we examined the multiscale nested runoff characteristics (lag time and magnitude) of the rural and urban flow components, assessed how these integrated with changing land use and increasing scale, and discussed the implications for flood management in the catchment. The analyses indicated three distinctly different

  19. North-South Partnership in Training and Education in Space Research and Application

    NASA Astrophysics Data System (ADS)

    Balogun, E.

    tackled by capturing the interest of young people in science, by appealing to space science. This is an area of cooperation in which complementarities of experience, stemming from different cultural origins can yield positive results. Researches into the utilization of space-based observation to monitor and control environmental resources (forests, oceans, atmosphere etc.) and climate change, are other examples of areas in which North-South Space Research and Application partnership can be established and sustained. Another area of partnership is in the development of space-based experiments, especially in the area of Communication Satellites, Earth threatening Asteroids and Comets, Global Navigation Satellites Systems, and the promotion of public awareness in space science and technology applications. Such activities will encourage mutual exchange of ideas and intellectual input by both partners in the progress, as opposed to a unilateral transfer of ideas from one partner to the other. Collaborative projects between partners from the North and South should involve university systems, the polytechnics, elementary and secondary school systems, colleges of education, research centers and organizations, corporate enterprise training, the Internet, and all those institutions whose responsibilities are to manage education and training in the developing world. Partnership in space science and technology, if nurtured in these institutions, can in the long run become one of mutual interaction, and can be sustained for a very long time.

  20. North-South Partnership in Training and Education in Space Research and Application

    NASA Astrophysics Data System (ADS)

    Balogun, E.

    tackled by capturing the interest of young people in science, by appealing to space science. This is an area of cooperation in which complementarities of experience, stemming from different cultural origins can yield positive results. Researches into the utilization of space-based observation to monitor and control environmental resources (forests, oceans, atmosphere etc.) and climate change, are other examples of areas in which North-South Space Research and Application partnership can be established and sustained. Another area of partnership is in the development of space-based experiments, especially in the area of Communication Satellites, Earth threatening Asteroids and Co mets, Global Navigation Satellites Systems, and the promotion of public awareness in space science and technology applications. Such activities will encourage mutual exchange of ideas and intellectual input by both partners in the progress, as opposed to a unilateral transfer of ideas from one partner to the other. Collaborative projects between partners from the North and South should involve university systems, the polytechnics, elementary and secondary school systems, colleges of education, research centers and organizations, corporate enterprise training, the Internet, and all those institutions whose responsibilities are to manage education and training in the developing world. Partnership in space science and technology, if nurtured in these institutions, can in the long run become one of mutual interaction, and can be sustained for a very long time.

  1. Transient Hydraulic Tomography at the North Campus Research Site, University of Waterloo

    NASA Astrophysics Data System (ADS)

    Berg, S. J.; Illman, W. A.

    2009-12-01

    Delineating the subsurface distribution of hydraulic conductivity (K) and specific storage (Ss) is of great importance in many areas of hydrogeology, especially for water supply and contaminant transport investigations. However, acquiring reliable distributions of such hydraulic parameters is often difficult and expensive. Hydraulic tomography has recently been proposed as an alternative to traditional geostatistical methods for imaging subsurface K and Ss distributions. The technique has been tested by various researchers using synthetic simulations and laboratory experiments. It has also been evaluated in the field at a number of sites in different geologic settings. Recently, we conducted transient hydraulic tomography (THT) at the North Campus Research Site (NCRS) situated at the University of Waterloo in a highly heterogeneous glaciofluvial aquifer-aquitard sequence. A plot measuring 15 m by 15 m and approximately 18 m deep was instrumented with four, 7-channel Continuous Multichannel Tubing (CMT) wells consisting of a total of 28 observation ports. Each observation port was instrumented with a pressure transducer to record the response of the system to pumping. These 4 CMT wells were situated in a square pattern with a multi-screen pumping well (eight pumping screens, one every two meters) located in the center. To date, 7 intervals along the center well have been pumped using a straddle-packer system. We interpreted 3 of the 7 pumping tests using two different approaches. In the first approach, the 3 pumping tests were analyzed via THT to obtain the K and Ss distributions (or tomograms) without including any available K measurements from the permeameter analysis of core samples for purposes of conditioning. In the second approach, we conducted the THT analysis by conditioning the K and Ss tomograms with available small scale data. Results to date show that K and Ss tomograms are consistent with site geology and other small scale measurements from the site.

  2. Perceptions of cancer clinical research among African American men in North Carolina

    PubMed Central

    Trantham, Laurel C.; Carpenter, William R; DiMartino, Lisa D.; White, Brandolyn; Green, Melissa; Teal, Randall; Corbie-Smith, Giselle; Godley, Paul A.

    2015-01-01

    Objective The problem of cancer health disparities is substantial. Clinical trials are widely advocated as a means of reducing disparities and bringing state-of-the-art care to the broader community, where most cancer care is delivered. This study sought to develop a better understanding of why disproportionately few African American men enroll in clinical trials given their substantial cancer burden. Design This study applied community-based participatory research (CBPR) methods to design and conduct four focus groups of African American male cancer survivors and their caregivers in North Carolina. Results Among major themes, participants expressed confusion about the relationship between clinical trials, treatment, and research, signifying patient confusion and misinterpretation of common clinical trial terminology. Social norms including gender barriers and generational differences remain problematic; participants often reported that men do not talk about health issues, are unwilling to go to the doctor, and exhibit misapprehension and distrust regarding trials. Participants perceived this as detrimental to community health and expressed the need for more clarity in clinical trials information and a more fundamental social openness and communication about cancer detection and treatment. Conclusion Findings indicate the importance of clinical trials education in both traditional provider referral to trials and also in general patient navigation. To dispel pervasive misapprehension regarding placebos, clinical trials information should emphasize the role of standard care in modern cancer treatment trials. Many participants described willingness to participate in a trial upon physician recommendation, suggesting merit in improving patient-physician communication through culturally competent terminology and trial referral systems. PMID:26113749

  3. Tidal fluxes of dissolved oxygen at the North Inlet-Winyah Bay National Estuarine Research Reserve

    NASA Astrophysics Data System (ADS)

    Gardner, L. R.; Kjerfve, B.; Petrecca, D. M.

    2006-04-01

    Advective, dispersive and total dissolved oxygen (DO) fluxes from 1297 complete tidal cycles were analyzed to test the "outwelling" hypothesis as it pertains to DO. A 910 day time series of meteorological and water quality data (approximately 35,000 half-hourly observations) was used to assess DO fluxes and dynamics at Crab Haul Creek, a small (1.1 km 2) tidal salt marsh basin at North Inlet, South Carolina, within the North Inlet-Winyah Bay National Estuarine Research Reserve. A basin storage curve, derived from water velocity measurements made across a permanent transect in the tidal creek every half hour for eight semidiurnal tidal cycles, enabled water discharges to be estimated from tide height readings in the 910 day time series. The discharges along with DO concentration measurements were used to calculate DO fluxes for each tidal cycle in the series. The long-term mean dispersive and advective DO fluxes were -0.281 g O 2 s -1 and -0.375 g O 2 s -1, respectively. Based on " t" tests both means are significantly less than zero ( p < 0.02), indicating exports. Furthermore a significant correlation was found between the dispersive DO export and the tidal mean solar radiation, indicating that photosynthesis is the principal process driving the dispersive export of DO. On the other hand no significant correlations were found between the advective export of DO and solar radiation or between the dispersive fluxes of DO and salt. The absence of such correlations indicates that the advective export of DO is simply an artifact of a slight ebb sampling bias in our computation of the tidal mean discharge. On a unit area basis the average annual dispersive export of DO is 8.9 g m -2 yr -1 or 0.28 mol DO m -2 yr -1. This is a small fraction of the oxygen produced in the basin by phytoplankton (18 mol DO m -2 yr -1) and its contribution to the DO resources of the receiving waters is far exceeded by the oxygen demand associated with the concurrent export of dissolved

  4. Atmospheric Research and Public Outreach Activities at Grandfather Mountain, North Carolina

    NASA Astrophysics Data System (ADS)

    Perry, B.; Pope, J.; Kelly, G.; Sherman, J. P.; Taubman, B.

    2012-12-01

    Promoting scientific and public understanding of mountain meteorological processes, particularly in the context of climate variability and change, remains a formidable challenge. Mountain environments present considerable difficulties in the collection of surface and atmospheric observations due to complex topography and resulting high spatial and temporal variability of the atmospheric processes. A collaborative partnership between Appalachian State University (ASU) and the Grandfather Mountain Stewardship Foundation (GMSF) in the southern Appalachian Mountains of North Carolina has provided an outstanding opportunity to integrate atmospheric research and outreach activities. The NASA-funded Climate Action Network through Direct Observations and Outreach (CAN-DOO) project directly supports the research and education activities and places them in the context of climate variability and change. This paper introduces the manual observations and citizen science activities, automated meteorological measurements, and public outreach initiatives on Grandfather Mountain and presents preliminary findings. In support of project objectives, GMSF staff makes daily measurements of precipitation, snow water equivalent, snow depth, and aerosol optical depth, while also encouraging citizen scientists to participate in the daily meteorological measurements. Team members have developed real-time displays of meteorological conditions for the two main visitor's centers and website, and have also created interactive climate science public displays. ASU scientists and GMSF staff have worked together to install and operate two research-quality meteorological stations at 1609 m asl that measure temperature, relative humidity, wind speed and direction, pressure, precipitation, and present weather. Preliminary results of research activities suggest that extreme wind gusts >50 m s -1 and severe icing due to riming and freezing rain are a frequent occurrence on Grandfather Mountain

  5. USGS research on geohazards of the North Pacific: past, present, and future

    NASA Astrophysics Data System (ADS)

    McNutt, M. K.; Eichelberger, J. C.

    2012-12-01

    The disastrous earthquakes and tsunamis of Sumatra in 2004 and Tohoku in 2011 have driven re-examination of where and how such events occur. Particular focus is on the North Pacific. Of the top 30 earthquakes recorded instrumentally worldwide, 50% occurred along the line of subduction from the Kuril Islands to the southern Alaska mainland. This region has seen monstrous volcanic eruptions (Katmai-Novarupta, 1912), destructive tsunamis (Severo-Kurilsk, 1952), and one of Earth's largest instrumentally-recorded earthquakes (M9.2 Alaska, 1964). Only the modest populations in these frontier towns half a century ago kept losses to a minimum. Impact of any natural disaster to population, vital infrastructure, and sea and air transportation would be magnified today. While USGS had a presence in Alaska for more than a century, the great Alaska earthquake of 1964 ushered in the first understanding of the area's risks. This was the first mega-thrust earthquake properly interpreted as such, and led to re-examination of the 1960 Chilean event. All modern conceptions of mega-thrust earthquakes and tsunamis derive some heritage from USGS research following the 1964 event. The discovery of oil in the Alaska Arctic prompted building a pipeline from the north slope of Alaska to the ice-free port of Valdez. The USGS identified risks from crossing permafrost and active faults. Accurate characterization of these hazards informed innovative designs that kept the pipeline from rupturing due to ground instability or during the M7.9 Denali earthquake of 2002. As a large state with few roads, air travel is common in Alaska. The frequent ash eruptions of volcanoes in the populous Cook Inlet basin became a serious issue, highlighted by the near-crash of a large passenger jet in 1989. In response, the USGS and its partners developed and deployed efficient seismic networks on remote volcanoes and initiated regular satellite surveillance for early warning of ash eruptions. Close collaboration

  6. On the advantage of a dynamic evaluation of catchment models - two Swedish case studies

    NASA Astrophysics Data System (ADS)

    Clemenzi, Ilaria; Seibert, Jan; Fenicia, Fabrizio; Kavetski, Dmitri; Lyon, Steve; Laudon, Hjalmar

    2010-05-01

    In two different case studies we illustrate how the application of a "dynamic identifiability analysis" approach can be a useful tool both for identifying model deficiencies, and thus guiding model improvement, and for detecting changes of catchments characteristics over time. This type of analysis consists of evaluating a hydrological model in a moving time window, which allows the assessment of time-variable parameter values. Here, the analysis was performed using the SuperFlex modeling framework, which is a hydrological modeling tool that allows the generation of multiple alternative model structures. The first case study consists of applying the analysis on the Krycklan catchment, situated in the north-east of Sweden. The available hydrological data series cover a period of ten years (1997-2007) during which no significant changes occurred in the catchment. In the second case-study, the approach was applied to the sub-arctic Abiskojokken catchment located in northern Sweden. The available time series range from 1918 to 2007 and previous investigations indicated a time-change of catchment characteristics due to changing permafrost. In the first case study, the dynamic analysis helped identifying deficiencies in the model structure, which could subsequently be improved. In the second case study, the analysis contributed to evaluating changes of catchment characteristics and functioning. Time variable model parameters could be associated to time changing catchment characteristics. Overall, this study demonstrated how the dynamic model evaluation is a powerful diagnostic tool that can increase the understanding of catchment behavior.

  7. The catchment based approach using catchment system engineering

    NASA Astrophysics Data System (ADS)

    Jonczyk, Jennine; Quinn, Paul; Barber, Nicholas; Wilkinson, Mark

    2015-04-01

    The catchment based approach (CaBa) has been championed as a potential mechanism for delivery of environmental directives such as the Water Framework Directive in the UK. However, since its launch in 2013, there has been only limited progress towards achieving sustainable, holistic management, with only a few of examples of good practice ( e.g. from the Tyne Rivers trust). Common issues with developing catchment plans over a national scale include limited data and resources to identify issues and source of those issues, how to systematically identify suitable locations for measures or suites of measures that will have the biggest downstream impact and how to overcome barriers for implementing solutions. Catchment System Engineering (CSE) is an interventionist approach to altering the catchment scale runoff regime through the manipulation of hydrological flow pathways throughout the catchment. A significant component of the runoff generation can be managed by targeting hydrological flow pathways at source, such as overland flow, field drain and ditch function, greatly reducing erosive soil losses. Coupled with management of farm nutrients at source, many runoff attenuation features or measures can be co-located to achieve benefits for water quality and biodiversity. A catchment, community-led mitigation measures plan using the CSE approach will be presented from a catchment in Northumberland, Northern England that demonstrate a generic framework for identification of multi-purpose features that slow, store and filter runoff at strategic locations in the landscape. Measures include within-field barriers, edge of field traps and within-ditch measures. Progress on the implementation of measures will be reported alongside potential impacts on the runoff regime at both local and catchment scale and costs.

  8. Switching the poles in sexual and reproductive health research: implementing a research capacity-strengthening network in West and North Africa.

    PubMed

    Dossou, Jean-Paul; Assarag, Bouchra; Delamou, Alexandre; Van der Veken, Karen; Belaid, Loubna; Ouédraogo, Moctar; Khalfallah, Sonia; Aouras, Hayet; Diadhiou, Mohamed; Fassassi, Raïmi; Delvaux, Thérèse

    2016-01-01

    Health research capacities have been improved in Africa but still remain weak as compared to other regions of the World. To strengthen these research capacities, international collaboration and networking for knowledge and capacity transfer are needed. In this commentary, we present the Network for Scientific Support in the field of Sexual and Reproductive Health in West and North Africa, its priority research topics and discuss its implementation process. Established in January 2014, the Network aims at generating human rights and gender-based research fully carried out and driven by South based institutions. It is composed of 12 institutions including the Institute of Tropical Medicine of Antwerp (Belgium) and 11 institutions from eight Francophone West and North African countries. The key areas of interest of this network are health policies analysis and health system research in family planning, HIV prevention among vulnerable groups, quality of care and breast cancers. Since it started, seventeen research proposals based on locally relevant research questions have been developed. Among the seventeen proposals, eleven have been implemented. Several research institutions enhanced linkages with local representations of international partners such as UNFPA. The network is committed to strengthening methodological research capacities and soft skills such as fundraising, advocacy and leadership. Such competencies are strongly needed for developing an effective South-based leadership in Sexual and Reproductive Health research, and for achieving the Sustainable Development Goals. PMID:27502593

  9. Assimilation of Freeze-Thaw Observations into the NASA Catchment Land Surface Model

    NASA Astrophysics Data System (ADS)

    Farhadi, L.; Reichle, R. H.; De Lannoy, G. J.; Kimball, J. S.

    2013-12-01

    The land surface freeze/thaw (F/T) state plays a key role in the hydrological and carbon cycles and thus affects water and energy exchanges and net primary productivity at the land surface. To support the level 4 soil moisture and carbon products (value-added, i.e. using a combination of remote sensing data and modeling) for the planned NASA Soil Moisture Active Passive (SMAP) mission, an F/T assimilation algorithm is developed for the NASA Goddard Earth Observing System, version 5 (GEOS-5) modeling and assimilation framework. The algorithm includes a newly developed observation operator that diagnoses the landscape F/T state in the GEOS-5 Catchment land surface model. A rule-based approach that incorporates model and observational errors is developed and used for assimilating the categorical F/T measurements into the land surface model (F/T analysis). An Observing System Simulation Experiment is conducted using synthetically generated measurements of the F/T state for a region in North America (90-110oW longitude, 45-55oN latitude). The synthetic 'truth' is generated using the NASA Catchment land surface model forced with surface meteorological fields from the Modern-Era Retrospective Reanalysis for Research and Applications (MERRA). To generate synthetic measurements, the true categorical F/T state is corrupted with a prescribed amount of F/T classification error. The assimilation experiment employs the same Catchment model except that forcing errors (relative to truth) are introduced via the application of meteorological forcing fields from the Global Land Data Assimilation System (GLDAS). The effect of the F/T analysis and classification error on land surface temperature and soil temperature predictions is examined in this research.

  10. Comparison of three statistical downscaling methods for precipitation in the Hérault and Ebro catchments

    NASA Astrophysics Data System (ADS)

    Lassonde, Sylvain; Vrac, Mathieu; Ruelland, Denis; Dezetter, Alain

    2014-05-01

    The aim of the GICC project "REMedHE" (http://www.remedhe.org) is to evaluate and compare the evolution of water supply capacity under climatic and anthropogenic changes by 2050 on two Mediterranean catchments: the Hérault (South of France) and the Ebro (North East of Spain) catchments. Indeed, the Mediterranean region has been identified as a "hot spot" of climate change, especially for precipitation which is expected to globally decrease while water needs should continue to increase. To perform such a study, it is then necessary to simulate future water flows with hydrological models fed by high-resolution precipitation data representative of the future climate. To generate high-resolution climate simulations, three different statistical downscaling approaches have been applied. The first one consists in a deterministic transfer function based on a Generalized Additive Model (GAM). The second method involves a Stochastic Weather Generator (SWG), simulating local values from probability density functions conditioned by large-scale predictors. The third approach belongs to the "Model Output Statistics" (MOS) family, in bias correcting the large-scale distributions with respect to the local-scale ones, through the Cumulative Distribution Function transform CDFt approach. These statistical downscaling models were calibrated and cross-validated using the SAFRAN dataset (for Hérault catchment), a dataset compiled by HydroSciences Montpellier (for Ebro catchment) as local-scale reference and the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis outputs as predictors, over two time periods 1959-1984 and 1985-2010. Cross-validation analysis shows that the inter-annual variability of the yearly sum of precipitation from GAM is close to that from SAFRAN. However, daily variability and occurrence frequency are badly represented by GAM. On the opposite, SWG and one version of CDFt allow both the inter-annual and

  11. Vegetation impact on mean annual evapotranspiration at a global catchment scale

    NASA Astrophysics Data System (ADS)

    Peel, Murray C.; McMahon, Thomas A.; Finlayson, Brian L.

    2010-09-01

    Research into the role of catchment vegetation within the hydrologic cycle has a long history in the hydrologic literature. Relationships between vegetation type and catchment evapotranspiration and runoff were primarily assessed through paired catchment studies during the 20th century. Results from over 200 paired catchment studies from around the world have been reported in the literature. Two constraints on utilizing the results from paired catchment studies in the wider domain have been that the catchment areas studied are generally (1) small (<10 km2) and (2) from a narrow range of climate types. The majority of reported paired catchment studies are located in the USA (˜47%) and Australia (˜27%) and experience mainly temperate (Köppen C) and cold (Köppen D) climate types. In this paper we assess the impact of vegetation type on mean annual evapotranspiration through a large, spatially, and climatically diverse data set of 699 catchments from around the world. These catchments are a subset of 861 unregulated catchments considered for the analysis. Spatially averaged precipitation and temperature data, in conjunction with runoff and land cover information, are analyzed to draw broad conclusions about the vegetation impact on mean annual evapotranspiration. In this analysis any vegetation impact signal is assessed through differences in long-term catchment average actual evapotranspiration, defined as precipitation minus runoff, between catchments grouped by vegetation type. This methodology differs from paired catchment studies where vegetation impact is assessed through streamflow responses to a controlled, within catchment, land cover change. The importance of taking the climate type experienced by the catchments into account when assessing the vegetation impact on evapotranspiration is demonstrated. Tropical and temperate forested catchments are found to have statistically significant higher median evapotranspiration, by about 170 mm and 130 mm

  12. Progress in the identification of catchments with co-existent multiple steady states and finite resilience

    NASA Astrophysics Data System (ADS)

    Peterson, T. J.; Western, A. W.; Thyer, M. A.; Frost, A. J.

    2015-12-01

    Hydrology has implicitly assumed that catchments are infinitely resilient to droughts and floods. No matter the magnitude of the climatic disturbance, almost all hydrological models simulate full recovery and hence assume infinite resilience. Recent research shows that catchments can undergo fundamental change during major droughts and this change in behavior is not captured by rainfall-runoff models. To date, the field of hydrological resilience has relied on theoretical deterministic models or vague resilience concepts, with the identification of catchments with multiple steady states (henceforth, attractors) remaining elusive. This is primarily due to the challenges stochastic forcing introduces into quantifying disturbance and recovery, and because resilience theory does not adequately address stochastic forcing. Drawing from recent hydrological resilience theory on catchment disturbance and recovery, a data-driven hidden Markov model is proposed for identifying recovery to a different hydrological state following major climatic disturbances. Application to selected unregulated catchments within Victoria, Australia, shows that after the Millennium Drought (~1995-2010) some catchments are yet to recover and have persisted within a functionally different hydrological state compared to that prior to the drought. Conversely, some catchments fully recovered at the cessation of the drought. This provides the first known field evidence that some catchments may have multiple attractors. Additionally, catchments are shown to differ in their resistance to the drought, with some catchments switching to a drought state at the commencement of the meteorological drought while other catchments taking ~10 years to switch to a hydrological drought state. In addition to separating hydrological droughts from meteorological droughts, this research provides a pathway for quantifying catchment resilience and resistance to climatic disturbances.

  13. Human-Landscape interaction in cultivated lowland catchments (Louroux catchment, Loire Valley, France)

    NASA Astrophysics Data System (ADS)

    Cerdan, Olivier; Foucher, Anthony; Gay, Aurore; Salvador Blanes, Sébastien; Evrard, Olivier; Desmet, Marc

    2015-04-01

    Change of land use or agricultural practices are known to have high impacts on sediment transfer in catchments and rivers. Numerous studies have particularly illustrated these effects in sloping land in tropical areas undergoing deforestation. Much less attention has been paid to lowland humid areas, where permanent land uses have been plowed more recently. However recent studies reported significant erosion rates in these environments despite the gentle topography and the temperate climate. In order to quantify these changing fluxes of sediment, several instrumentation and historical database analyses were carried out in various catchments of the Loire Valley, France. More particularly, a multiparameter analysis was conducted on sedimentary deposits of a pond created in the 11th century in a catchment representative of cultivated and drained lowland environments where an intensification of agricultural practices has occurred during the last 60 years. The results showed that the initial land consolidation period (1954-1960) was characterized by a dominance of allochtonous material input to the pond. This input represents an erosion of 1900 to 2300 t.km-².yr-1 originating from the catchment. Then, between 1970-1990, terrigenous material flow decreased progressively and tended to stabilize, whereas eutrophication and associated primary production increased in the pond. In addition to these temporal changes, material input across the pond during the last 10 years corresponds to a loss of material in the catchment ranging between 90 and 102 t.km-2.yr-1. While a strong decrease is observed, it still represents a 60-fold increase of the sediment fluxes to the pond compared to the preintensification period. Subsequent research monitoring studies permitted to differentiate between the different sources of sediment and highlight the importance of surface erosion during flood events and of bank erosion during low flows. The increased export of the sediment is primarily due

  14. Inter-comparison of hydro-climatic regimes across northern catchments: Synchronicity, resistance and resilience

    USGS Publications Warehouse

    Carey, S.K.; Tetzlaff, D.; Seibert, J.; Soulsby, C.; Buttle, J.; Laudon, H.; McDonnell, J.; McGuire, K.; Caissie, D.; Shanley, J.; Kennedy, M.; Devito, K.; Pomeroy, J.W.

    2010-01-01

    The higher mid-latitudes of the Northern Hemisphere are particularly sensitive to climate change as small differences in temperature determine frozen ground status, precipitation phase, and the magnitude and timing of snow accumulation and melt. An international inter-catchment comparison program, North-Watch, seeks to improve our understanding of the sensitivity of northern catchments to climate change by examining their hydrological and biogeochemical responses. The catchments are located in Sweden (Krycklan), Scotland (Mharcaidh, Girnock and Strontian), the United States (Sleepers River, Hubbard Brook and HJ Andrews) and Canada (Catamaran, Dorset and Wolf Creek). This briefing presents the initial stage of the North-Watch program, which focuses on how these catchments collect, store and release water and identify 'types' of hydro-climatic catchment response. At most sites, a 10-year data of daily precipitation, discharge and temperature were compiled and evaporation and storage were calculated. Inter-annual and seasonal patterns of hydrological processes were assessed via normalized fluxes and standard flow metrics. At the annual-scale, relations between temperature, precipitation and discharge were compared, highlighting the role of seasonality, wetness and snow/frozen ground. The seasonal pattern and synchronicity of fluxes at the monthly scale provided insight into system memory and the role of storage. We identified types of catchments that rapidly translate precipitation into runoff and others that more readily store water for delayed release. Synchronicity and variance of rainfall-runoff patterns were characterized by the coefficient of variation (cv) of monthly fluxes and correlation coefficients. Principal component analysis (PCA) revealed clustering among like catchments in terms of functioning, largely controlled by two components that (i) reflect temperature and precipitation gradients and the correlation of monthly precipitation and discharge and (ii

  15. Modeller's attitude in catchment modelling: a comparative study

    NASA Astrophysics Data System (ADS)

    Battista Chirico, Giovanni

    2010-05-01

    Ten modellers have been invited to predict, independently from each other, the discharge of the artificial Chicken Creek catchment in North-East Germany for simulation period of three years, providing them only soil texture, terrain and meteorological data. No data concerning the discharge or other sources of state variables and fluxes within the catchment have been provided. Modellers had however the opportunity to visit the experimental catchment and inspect areal photos of the catchments since its initial development stage. This study has been a unique comparative study focussing on how different modellers deal with the key issues in predicting the discharge in ungauged catchments: 1) choice of the model structure; 2) identification of model parameters; 3) identification of model initial and boundary conditions. The first general lesson learned during this study was that the modeller is just part of the entire modelling process and has a major bearing on the model results, particularly in ungauged catchments where there are more degrees of freedom in making modelling decisions. Modellers' attitudes during the stages of the model implementation and parameterisation have been deeply influenced by their own experience from previous modelling studies. A common outcome was that modellers have been mainly oriented to apply process-based models able to exploit the available data concerning the physical properties of the catchment and therefore could be more suitable to cope with the lack of data concerning state variables or fluxes. The second general lesson learned during this study was the role of dominant processes. We believed that the modelling task would have been much easier in an artificial catchment, where heterogeneity were expected to be negligible and processes simpler, than in catchments that have evolved over a longer time period. The results of the models were expected to converge, and this would have been a good starting point to proceed for a model

  16. The U.S. Department of Energy's Atmospheric Radiation Measurement Climate Research Facilities on the North Slope of Alaska

    NASA Astrophysics Data System (ADS)

    Ivey, M. D.; Verlinde, J.; Richardson, S.; Zak, B.; Zirzow, J.

    2008-12-01

    The U.S. Department of Energy (DOE) provides scientific infrastructure and data archives to the international Arctic research community through a national user facility, the ARM Climate Research Facilities (ACRF). One of three fixed ARM Climate Research Facilities is located on the North Slope of Alaska. Since 1998, these facilities near the communities of Barrow and Atqasuk have provided data about cloud and radiative processes at high latitudes. These data are used to refine models and parameterizations related to the Arctic. Data records from the instruments at these facilities and data products are available through web- accessible archives. The ACRF's role is to provide infrastructure support for climate research, including Arctic research, to the global scientific community. DOE's climate research programs, with a focus on clouds and aerosols and their impact on the radiative budget, define the research scope supported by the Facility. In addition to a set of baseline instruments at the two fixed North Slope ACRF locations, temporary or guest instruments are operated as required to support field campaigns. Recent field campaigns have included over-flights by aircraft with cloud and aerosol-sampling instrumentation. To support proposed deployments of unmanned aerial vehicle and unmanned aerial systems on the North Slope of Alaska and over the Arctic Ocean, permissions are being obtained and access arranged for use of a runway and nearby ground support facilities at Oliktok Point, Alaska. In addition to the fixed facilities, ARM Mobile Facilities may be used for high-latitude deployments. Deployments for the ARM Mobile Facilities are selected through a formal process that includes peer review of science-focused proposals. The first ARM Mobile Facility is nearing the end of a deployment in China. Design and development of a second ARM Mobile Facility will begin in late calendar year 2008. This paper discusses the scientific infrastructure, data streams and

  17. Multivariate analysis of a small pleistocene catchment: tracing hydrological change

    NASA Astrophysics Data System (ADS)

    Boettcher, Steven; Merz, Christoph; Dannowski, Ralf

    2013-04-01

    The water budget of catchments in north-east Germany has decreased considerably over the last decades. Especially small catchments are affected due to the small amount of water stored within. Climate projections for the next decades hint to even more negative impacts on the water budgets of these catchments. Therefore, a new concept of water resource management for this region must be developed, including counter measures to extreme events such as low and high flow conditions. In order to manage a hydrological system one needs to know the typical behavior and be able to effectively counteract if needed. Within the network activity INKA-BB (Inovationsnetzwerk Klimaanpassung Brandenburg Berlin) dealing with possible adaptation measures to climate change in the Brandenburg and Berlin region, this study aims at identifying the typical hydraulic behavior of the Fredersdorfer Mühlenfließ catchment located north-east of Berlin as a basis for a sustainable water resource management concept. Established schemes are followed, including the application of numerical geochemical and hydraulic models as well as chemical graphical interpretation approaches. A common problem is the sparse spatial as well as temporal resolution of the data at hand. Here, these schemes are too inflexible and vague with respect to analyzing and parameterization of complex features used for identifying operative hydraulic-geochemical processes including intensive non-linear interactions. Hence, methods must be applied that are able to effectively utilize the limited information available. Ordination methods such as the Principle Component Analysis (PCA) or the non-linear Isometric Feature Mapping (Isomap) can provide such a tool. Ordination methods are used in order to derive a meaningful low-dimensional representation of a high-dimensional input data set. The approach is based on the hypothesis, that the amount of processes which explain the variance of the data is relative low although the

  18. Management of North American Culicoides biting midges: Current knowledge and research needs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Culicoides biting midges (Diptera: Ceratopogonidae) are biological vectors of two important viruses infecting North American ruminants: bluetongue (BTV) and epizootic hemorrhagic disease (EHDV). While these viruses have been identified for over 60 years, we still lack an adequate understanding of t...

  19. 2010 North Plains Research Field 12-200 Limited Irrigation Corn Production Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The North Plains Groundwater Conservation District (NPGCD) in the Texas High Plains embarked on a demonstration program to illustrate if the region could produce 200 bushels and acres of corn using just 12 inches of irrigation water (named the 12-200 Project). This report is a summary of the first y...

  20. Disaster Down East: Using Participatory Action Research to Explore Intimate Partner Violence in Eastern North Carolina

    ERIC Educational Resources Information Center

    Frasier, Pamela York; Belton, Leigh; Hooten, Elizabeth; Campbell, Marci Kramish; DeVellis, Brenda; Benedict, Salli; Carrillo, Carla; Gonzalez, Pam; Kelsey, Kristine; Meier, Andrea

    2004-01-01

    In the aftermath of Hurricane Floyd in 1999, a Community Advisory Committee requested assistance from its university partners (University of North Carolina) to address stress and increased risk for intimate partner violence (IPV). Collected from 12 study work sites, baseline data indicated that IPV rates were higher among blue-collar women in…

  1. Model Store Curriculum. A Developmental Model for North Dakota Schools. Final Report. Research Series No. 13.

    ERIC Educational Resources Information Center

    Goschen, Todd; Warcup, Dennis

    The final report evaluates the activities of the first nine weeks of a project designed to develop a curriculum guide for a school-model store at a North Dakota high school. The program combines the favorable aspects of both the school store and the model store, providing "live" experiences as well as simulated ones. The Distributive Education One…

  2. Detecting non-stationary hydrologic model parameters in a paired catchment system using data assimilation

    NASA Astrophysics Data System (ADS)

    Pathiraja, S.; Marshall, L.; Sharma, A.; Moradkhani, H.

    2016-08-01

    Non-stationarity represents one of the major challenges facing hydrologists. There exists a need to develop modelling systems that are capable of accounting for potential catchment changes, in order to provide useful predictions for the future. Such changes may be due to climatic temporal variations or human induced changes to land cover. Extensive research has been undertaken on the impacts of land-use change on hydrologic behaviour, however, few studies have examined this issue in a predictive modelling context. In this paper, we investigate whether a time varying model parameter estimation framework that uses the principles of Data Assimilation can improve prediction for two pairs of experimental catchments in Western Australia. All catchments were initially forested, but after three years one catchment was fully cleared whilst another had only 50% of its area cleared. Their adjacent catchments remained unchanged as a control. Temporal variations in parameters were detected for both treated catchments, with no comparable variations for the control catchments. Improved streamflow prediction and representation of soil moisture dynamics were also seen for the time varying parameter case, compared to when a time invariant parameter set from the calibration period was used. While we use the above mentioned catchments to illustrate the usefulness of the approach, the methods are generic and equally applicable in other settings. This study serves as an important validation step to demonstrate the potential for time varying model structures to improve both predictions and modelling of changing catchments.

  3. Transmission and Epidemiology of Bluetongue and Epizootic Hemorrhagic Disease in North America: Current Perspectives, Research Gaps, and Future Directions.

    PubMed

    Ruder, Mark G; Lysyk, Timothy J; Stallknecht, David E; Foil, Lane D; Johnson, Donna J; Chase, Christopher C; Dargatz, David A; Gibbs, E Paul J

    2015-06-01

    Bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) are arthropod-transmitted viruses in the genus Orbivirus of the family Reoviridae. These viruses infect a variety of domestic and wild ruminant hosts, although the susceptibility to clinical disease associated with BTV or EHDV infection varies greatly among host species, as well as between individuals of the same species. Since their initial detection in North America during the 1950s, these viruses have circulated in endemic and epidemic patterns, with occasional incursions to more northern latitudes. In recent years, changes in the pattern of BTV and EHDV infection and disease have forced the scientific community to revisit some fundamental areas related to the epidemiology of these diseases, specifically in relation to virus-vector-host interactions and environmental factors that have potentially enabled the observed changes. The aim of this review is to identify research and surveillance gaps that obscure our understanding of BT and EHD in North America. PMID:26086556

  4. On using TRMM data and rainfall forecasts from meteorological models in data-scarce transboundary catchments - an example of Bangladesh

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Biswa; Tohidul Islam, Md.

    2014-05-01

    This research focuses on the flood risk of the Haor region in the north-eastern part of Bangladesh. The prediction of the hydrological variables at different spatial and temporal scales in the Haor region is dependent on the influence of several upstream rivers in the Meghalaya catchment in India. Limitation in hydro-meteorological data collection and data sharing issues between the two countries dominate the feasibility of hydrological studies, particularly for near-realtime predictions. One of the possible solutions seems to be in making use of the variety of satellite based and meteorological model products for rainfall. The abundance of a variety of rainfall products provides a good basis of hydrological modelling of a part of the Ganges and Brahmaputra basin. In this research the TRMM data and rainfall forecasts from ECMWF have been compared with the scarce rain gauge data from the upstream Meghalaya catchment. Subsequently, the TRMM data and rainfall forecasts from ECMWF have been used as the meteorological input to a rainfall-runoff model of the Meghalaya catchment. The rainfall-runoff model of Meghalaya has been developed using the DEM data from SRTM. The generated runoff at the outlet of Meghalaya has been used as the upstream boundary condition in the existing rainfall-runoff model of the Haor region. The simulation results have been compared with the existing results based on simulations without any information of the rainfall-runoff in the upstream Meghalaya catchment. The comparison showed that the forecasting lead time has been substantially increased. As per the existing results the forecasting lead time at a number of locations in the catchment was about 6 to 8 hours. With the new results the forecasting lead time has gone up, with different levels of accuracy, to about 24 hours. This additional lead time will be highly beneficial in managing flood risk of the Haor region of Bangladesh. The research shows that satellite based rainfall products and

  5. Research of water resources allocation of South-to-North Water Diversion East Route Project in Jiangsu Province ,Eastern China

    NASA Astrophysics Data System (ADS)

    Zeng, C.

    2015-12-01

    Optimized allocation of water resources is the important means of solving regional water shortage and can improve the utilization of water resources. Water resources allocation in the large-scale water diversion project area is the current research focus. This research takes the east route of the South-to-North Water Transfer Project in Jiangsu province as the research area, based on the hydrological model, agricultural irrigation quota model, and water project scheduling model, a water resources allocation model was constructed. The research carried on generalized regional water supply network, simulated the water supply, water demand and water deficit in agriculture, industry, life, ecology and lock under the status quo and planning engineering conditions. According to the results, the east route of the South-to-North Water Transfer Project is helpful to improve regional water shortage situation. The results showed that pump output increase by 2.8 billion cubic meters of water. On the conditions of P = 95%, 75% and 50%, compared with the benchmark year, water demand increases slightly due to the need of social and economic development in planning years, and water supply increased significantly because of new diversion ability. Water deficit are greatly reduced by 74.9% especially in the commonly drought condition because of the new project operation and optimized allocation of water resources.

  6. Relative influence of upland and lowland headwaters on the isotope hydrology and transit times of larger catchments

    NASA Astrophysics Data System (ADS)

    Tetzlaff, D.; Soulsby, C.; Hrachowitz, M.; Speed, M.

    2011-04-01

    SummaryWeekly variation of δ 18O was measured over 2 years in precipitation and river water in four relatively large catchments in north east Scotland. The River Dee (1712 km 2) is predominantly upland, with impermeable geology and hydrologically responsive soils. The headwaters of the River North Esk (732 km 2) are similar, but the lower third of the catchment is underlain by a major sandstone aquifer and is lowland (i.e. <300 m altitude) in nature. The upper 20% of the River Don catchment (1273 km 2) is upland, but the remainder is lowland with freely draining soils recharging significant groundwater reservoirs in superficial drifts. The River Ythan catchment (662 km 2) is entirely lowland and similar to the lower Don. The hydrological responsiveness of the catchments was directly related to their upland area, with the Dee and the North Esk generating the highest specific discharges during high flow events. Conversely, the Don and Ythan had more subdued hydrological regimes, but higher specific discharge under baseflows. Despite broadly similar δ 18O variation in precipitation inputs, the variability of stream waters was increasingly damped in the order Ythan > Don > North Esk > Dee. Convolution integral models were used to estimate Mean Transit Times (MTTs) for the four catchments from the isotope data. These were reasonably well-constrained at around 2 years for the Dee and 3 years for the North Esk. Estimates for the Don and Ythan were poorly constrained and therefore highly uncertain, but are both likely to exceed 10 years. MTTs in upland catchments in the Scottish Highlands are relatively short (ca. 2 months-4 years) and have been shown to be strongly correlated with soil hydrology, topographic indices and precipitation intensity. However, these relationships change in lowland areas as catchments become less surface water dominated and greater groundwater storage and deeper mixing processes result in much higher MTTs. Nevertheless, a close correlation

  7. Characterizing Runoff and Water Yield from Headwater Catchments in the Southern Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Safeeq, M.; Hunsaker, C. T.

    2015-12-01

    In a mediterranean climate where much of the annual precipitation falls during winter, the snow-capped Sierra Nevada serves as the primary source of dry season runoff that supports agriculture, industries, urban, and other ecosystems. Increased warming has led to significant reductions in mountain snowpack accumulation and earlier snowmelt throughout the western United States where most of the snow accumulates at temperatures near the freezing point. As a result, declines in dry season runoff magnitude, earlier runoff timing, and altered flood risk have been reported across the region. An important question in this context is, how to best manage forested catchments for water and other ecosystem services? We depict the differences in hydrologic response of ten catchments in the Kings River Experimental Watersheds (KREW) research project using continuous precipitation, snow, and runoff data during 2004-2014. The size of these catchments ranges from 50 to 475 ha, and they span a 600-m elevation range in the rain snow transitional zone. In terms of soil, Shaver and Gerle-Cagwin dominate the lower elevation Providence catchments, and Cagwin soils dominate the higher elevation Bull catchments. The majority of these catchments have southwest aspect, moderate average slope (i.e. <25%), and a well-developed drainage network with drainage density ranging from 4.6 to 10.1 km/km2. Bull catchments, on average, have higher runoff than the Providence catchments across all hydrologic signatures extracted from daily hydrographs. Mean annual runoff ranges between 281 to 408 mm in Providence and 436 to 656 mm in Bull catchments despite no significant difference in precipitation among KREW's four meteorological stations. However, high elevation Bull catchments receive significantly more precipitation as snow than the low elevation Providence catchments. The average runoff ratio ranges from 18% to as high as 43% among different catchments, indicating that the catchment

  8. Phosphorus fluxes in headwater streams draining non-research poultry-pasture operations in north-central Georgia, USA

    NASA Astrophysics Data System (ADS)

    Romeis, J. J.; Jackson, C. R.; Radcliffe, D. E.; Risse, M. L.; Bryant, J.

    2007-12-01

    Poultry production is the largest agricultural commodity in Georgia, USA. Due to inefficient utilization of the phosphorus (P) in poultry feed, the manure contains high concentrations of P. When used as fertilizer for crops and pasture, poultry manure may be washed from the soil surface and increase eutrophication risks to downstream lakes and reservoirs. Long term application of poultry manure may result in P saturation of the soils. In the upper Etowah River basin in north-central Georgia, a long history of poultry farming has resulted in high P levels in soils receiving regular poultry manure applications. Few studies to date have been performed on the estimation of P fluxes from operational commercial poultry farms in Georgia. In Fall 2006, a 20-month surface water quality monitoring program was completed that was aimed at estimating P and suspended sediment fluxes in nine headwater streams draining poultry-pasture operations in the upper Etowah River basin. The nine catchments differed in terms of land use history, soil P levels, best management practices and other factors. An additional three streams draining U.S. National Forest were also monitored to provide reference concentrations and loads. Monitoring data included continuous (5-minute) streamflow, rainfall, and water quality samples. Water quality samples included biweekly grab samples plus storm samples collected using conventional autosamplers. Storm sampling using autosamplers included collection of discrete samples and composite samples. In particular instances, the two types of storm sample were collected simultaneously. Discrete storm sampling methods enabled collection of both rising and falling hydrograph limb samples to identify potential hysteretic water quality effects. Water samples were analyzed for total P, filterable reactive P, and total suspended solids. We are using this data to compare different flux estimation methods with emphasis on regression models that utilize laboratory results

  9. Collaborative Research: Climate Sensitivity of Thaw Lake Systems on the Alaska North Slope

    NASA Technical Reports Server (NTRS)

    Zhang, Tingjun; Jeffries, Martin O.

    2001-01-01

    There are thousands of thaw (thermokarst) lakes on the North Slope of Alaska, where they cover as much as 40% of the land area. Their very name recognizes the fact that they owe their origin to the impact they have on the ground thermal regime, but there have been few quantitative studies of the impact of the lakes on atmosphere-land interactions in this tundra region.

  10. Action research: the revision of services at one mental health rehabilitation unit in the north of England.

    PubMed

    Leighton, K

    2005-06-01

    This paper reports the experiences of people in one mental health rehabilitation unit in the north of England, where conventional individualized approaches have repeatedly failed, leading to bed blocking and inertia. An action research approach has been used to identify the key problems concerned, construct appropriate goals and formulate problem-solving plans, leading to the development of an alternative therapeutic regime. The new facility is based on a society-centred, recovery approach which emphasizes the principles of community involvement, social responsibility and meaningful occupation of time. This approach may be of transferable interest to others in the field. The paper outlines the history of the unit, describes the action research process, and presents the philosophy of care, nursing model, admission criteria and main assessment tool now being used. It concludes with an open review of the research process, exploring both positive and negative aspects. PMID:15876246

  11. North-South Partnership in Water Resource Education and Research - Lessons learnt from U.S.-Ethiopia Partnership

    NASA Astrophysics Data System (ADS)

    Gebremichael, M.

    2015-12-01

    In 2010, Ethiopian and U.S. universities formed partnership to train critical mass of Ethiopians in modern water resources tools, techniques, skills and knowledge, and to strengthen the institutional capacity of Ethiopian universities to establish graduate-level programs in Ethiopia. The partnership established Ethiopia's first water resource research institute, two graduate-level programs (water resource engineering and management, water and health) that are currently training about 100 students at M.S. and Ph.D. levels, summer undergraduate outreach program that provided community-based research experience in water resource for undergraduate students, and short-term trainings to practitioners and policy makers. The design, implementation and impact of these programs have had limitations and successes. In this presentation, I will provide lessons learnt from this partnership, and suggestions of elements required for successful North-South partnership in higher education and research.

  12. Optimization of precipitation inputs for SWAT modeling in mountainous catchment

    NASA Astrophysics Data System (ADS)

    Tuo, Ye; Chiogna, Gabriele; Disse, Markus

    2016-04-01

    Precipitation is often the most important input data in hydrological models when simulating streamflow in mountainous catchment. The Soil and Water Assessment Tool (SWAT), a widely used hydrological model, only makes use of data from one precipitation gauging station which is nearest to the centroid of each subcatchment, eventually corrected using the band elevation method. This leads in general to inaccurate subcatchment precipitation representation, which results in unreliable simulation results in mountainous catchment. To investigate the impact of the precipitation inputs and consider the high spatial and temporal variability of precipitation, we first interpolated 21 years (1990-2010) of daily measured data using the Inverse Distance Weighting (IDW) method. Averaged IDW daily values have been calculated at the subcatchment scale to be further supplied as optimized precipitation inputs for SWAT. Both datasets (Measured data and IDW data) are applied to three Alpine subcatchments of the Adige catchment (North-eastern Italy, 12100 km2) as precipitation inputs. Based on the calibration and validation results, model performances are evaluated according to the Nash Sutchliffe Efficiency (NSE) and Coefficient of Determination (R2). For all three subcatchments, the simulation results with IDW inputs are better than the original method which uses measured inputs from the nearest station. This suggests that IDW method could improve the model performance in Alpine catchments to some extent. By taking into account and weighting the distance between precipitation records, IDW supplies more accurate precipitation inputs for each individual Alpine subcatchment, which would as a whole lead to an improved description of the hydrological behavior of the entire Adige catchment.

  13. Interventions to Promote Energy Balance and Cancer Survivorship: European and North American Priorities for Research and Care

    PubMed Central

    Alfano, Catherine M.; Molfino, Alessio; Muscaritoli, Maurizio

    2013-01-01

    The growing population of cancer survivors worldwide and the growing epidemics of obesity and physical inactivity have brought increased attention to the role that interventions to promote exercise and a healthy body weight might play in mitigating the chronic and late effects of cancer. In this light, we describe the similarities and differences in research and clinical priorities related to energy balance interventions among post-treatment cancer survivors in Europe vs. North America. We review the randomized, controlled trials targeting nutrition, exercise, and weight to affect survivorship outcomes. We discuss the interventions focused on improving prognosis or survival, as well as the emerging literature on interventions targeting pathways and mechanisms of prognosis or survival. We describe current North American and European guidelines for diet, exercise, and weight control among cancer survivors and discuss implications of the current state of this science for clinical care. Finally, we delineate future European and American priorities for research and care involving energy balance among survivors. We hope that this dialogue launches an international conversation that will lead to better research and care for all post-treatment cancer survivors. PMID:23695926

  14. BIOLOGICAL SINKS FOR N ADDITIONS TO A FORESTED CATCHMENT

    EPA Science Inventory

    The goal of our research is to identify and quantify sinks for experimental Nitrogen (N) additions to a forested catchment at the Bear Brooks Watershed in Maine (BBWM) where background N deposition rates are low (< 4 kg ha-1 yr1). itrogen is added bimonthly to an experimental cat...

  15. On the value of data for catchment modelling.

    NASA Astrophysics Data System (ADS)

    Fenicia, F.; McDonnell, J. J.; Savenije, H. H.; Pfister, L.

    2006-12-01

    The dialogue between experimentalist and modeller in catchment hydrology continues to be minimal, despite the clear need for this to quantify and reduce uncertainty in our predictions. Experimentalists often instrument catchments to measure key diagnostic properties and variables that, from their perspective, characterize catchment behaviour. Typically, after some years, the research switches to the hands of the catchment modeller who uses these data to support model development or to constrain a model's degrees of freedom. Often there is frustration on the part of the modeller because only a small part of the collected information can be actually used for the set-up, calibration and evaluation of the hydrological model. Much of the field data turns out to be of little use for modelling, for problems that may be related to the disparity between the scale of measurements and the scale of model components. This happens not only because of a lack of communication between modellers and experimentalists, but also because the information requirements of a model are seldom treated as a scientific issue. We use the well-studied Maimai catchment to explore what types of measurements, what length of time series and what resolution in time and space is best suited for modellers, in a way that it can be processed into simple, integrative evaluative data that constrain the model so as to represent the hydrological processes realistically. We discuss the marginal value of different data sources and the tradeoffs between time spent completing time series for a few variables and locations to spatially distributed snapshots of different variables aimed at increasing data complementarity. A first direct application of this study will be to orientate future field research on the experimental catchments operating in the Grand Duchy of Luxembourg.

  16. Population dynamics of the major north American needle-eating budworms. Forest Service research paper

    SciTech Connect

    Campbell, R.W.

    1993-04-01

    The report includes data from six western States provided 1,251 life tables representing western spruce budworm, Choristoneura occidentalis. These data provided projection capabilities for defoliation and successive budworm densities, as well as a basis for comparing survival rates among the three principal North American needle-eating budworms (western and eastern spruce budworms, and the jack pine budworm). Several modifications are suggested in current methods for managing budworm susceptible forests, and suggestions are provided for further studies on the budworm life systems.

  17. Describing Ecosystem Complexity through Integrated Catchment Modeling

    NASA Astrophysics Data System (ADS)

    Shope, C. L.; Tenhunen, J. D.; Peiffer, S.

    2011-12-01

    Land use and climate change have been implicated in reduced ecosystem services (ie: high quality water yield, biodiversity, and agricultural yield. The prediction of ecosystem services expected under future land use decisions and changing climate conditions has become increasingly important. Complex policy and management decisions require the integration of physical, economic, and social data over several scales to assess effects on water resources and ecology. Field-based meteorology, hydrology, soil physics, plant production, solute and sediment transport, economic, and social behavior data were measured in a South Korean catchment. A variety of models are being used to simulate plot and field scale experiments within the catchment. Results from each of the local-scale models provide identification of sensitive, local-scale parameters which are then used as inputs into a large-scale watershed model. We used the spatially distributed SWAT model to synthesize the experimental field data throughout the catchment. The approach of our study was that the range in local-scale model parameter results can be used to define the sensitivity and uncertainty in the large-scale watershed model. Further, this example shows how research can be structured for scientific results describing complex ecosystems and landscapes where cross-disciplinary linkages benefit the end result. The field-based and modeling framework described is being used to develop scenarios to examine spatial and temporal changes in land use practices and climatic effects on water quantity, water quality, and sediment transport. Development of accurate modeling scenarios requires understanding the social relationship between individual and policy driven land management practices and the value of sustainable resources to all shareholders.

  18. Evaluation of TOPLATS on three Mediterranean catchments

    NASA Astrophysics Data System (ADS)

    Loizu, Javier; Álvarez-Mozos, Jesús; Casalí, Javier; Goñi, Mikel

    2016-08-01

    Physically based hydrological models are complex tools that provide a complete description of the different processes occurring on a catchment. The TOPMODEL-based Land-Atmosphere Transfer Scheme (TOPLATS) simulates water and energy balances at different time steps, in both lumped and distributed modes. In order to gain insight on the behavior of TOPLATS and its applicability in different conditions a detailed evaluation needs to be carried out. This study aimed to develop a complete evaluation of TOPLATS including: (1) a detailed review of previous research works using this model; (2) a sensitivity analysis (SA) of the model with two contrasted methods (Morris and Sobol) of different complexity; (3) a 4-step calibration strategy based on a multi-start Powell optimization algorithm; and (4) an analysis of the influence of simulation time step (hourly vs. daily). The model was applied on three catchments of varying size (La Tejeria, Cidacos and Arga), located in Navarre (Northern Spain), and characterized by different levels of Mediterranean climate influence. Both Morris and Sobol methods showed very similar results that identified Brooks-Corey Pore Size distribution Index (B), Bubbling pressure (ψc) and Hydraulic conductivity decay (f) as the three overall most influential parameters in TOPLATS. After calibration and validation, adequate streamflow simulations were obtained in the two wettest catchments, but the driest (Cidacos) gave poor results in validation, due to the large climatic variability between calibration and validation periods. To overcome this issue, an alternative random and discontinuous method of cal/val period selection was implemented, improving model results.

  19. Hydrological Controls on Nutrient Concentrations and Fluxes in Agricultural Catchments

    NASA Astrophysics Data System (ADS)

    Petry, J.; Soulsby, C.

    2002-12-01

    This investigation into diffuse agricultural pollution and the hydrological controls that exert a strong influence on both nutrient concentrations and fluxes, was conducted in an intensively farmed lowland catchment in north-east Scotland. The study focuses on spatial and seasonal variations in nutrient concentrations and fluxes at the catchment scale, over a 15-month period. The water quality of the 14.5 km2 Newmills Burn catchment has relatively high nutrient levels with mean concentrations of NO3-N and NH3-N at 6.09 mg/l and 0.28 mg/l respectively. Average PO4-P concentrations are 0.06 mg/l. Over short timescales nutrient concentrations and fluxes are greatest during storm events when PO4-P and NH3-N are mobilised by overland flow in riparian areas, where soils have been compacted by livestock or machinery. Delivery of deeper soil water in subsurface storm flow, facilitated by agricultural under-drainage, produces a marked increase in NO3-N (6.9 mg/l) concentrations on the hydrograph recession limb. A more detailed insight into the catchment response to storm events, and in particular the response of the hydrological pathways which provide the main sources of runoff during storm events, was gained by sampling stream water at 2-hourly intervals during 5 events. End Member Mixing Analysis (EMMA) was carried out using event specific end-member chemistries to differentiate three catchment-scale hydrological pathways (overland flow, subsurface storm flow, groundwater flow) on the basis of observed Si and NO3-N concentrations in sampled source waters. Results show that overland flow generally dominates the storm peak and provides the main flow path by which P is transferred to stream channels during storm events, whilst subsurface storm flows usually dominate the storm hydrograph volumetrically and route NO3-rich soil water to the stream. The study shows that altering hydrological pathways in a catchment can have implications for nutrient management. Whilst buffer

  20. Carbon Dioxide Flooding Technology Research and Field Test in Liuzan North Block

    NASA Astrophysics Data System (ADS)

    Zhang, Hanshi; Luo, Pingya; Sun, Lei; Fu, Zhijun

    2014-12-01

    The fault roots of Liuzan north block in Jidong oilfield of China have been long-term explored by solution gas drive. Recently, oil production declined rapidly because of shortage of formation energy and needing high water injection pressure. Carbon dioxide injection pressure is found to be generally low, and CO2 has good solubility in crude oil to supply formation energy and achieve high oil recovery efficiency. In this work, a pilot program of CO2 EOR technology was carried out. The slim tube test results showed that the minimal miscible pressure of Liuzan north block was 28.28 MPa. The injection parameters were optimized by numerical simulation method: the injection method was continuous, the slug size was 0.2 HCPV and the EOR efficiency was 7.23%. After two months of gas injection field test, the formation pressure of two gas injectors just increased by 14.02 MPa and 2.98 MPa, respectively, indicating that carbon dioxide could supply the formation energy effectively. 16 months after gas injection, the CO2 injection amount was 14640 t, and the oil increment was 16424 t. The present work demonstrates the potential applicability of CO2 flooding technology from high water injection reservoirs.

  1. The relative influence of climate and catchment properties on hydrological drought

    NASA Astrophysics Data System (ADS)

    Van Loon, Anne; Laaha, Gregor; Koffler, Daniel

    2014-05-01

    high elevation, steep slopes, a high percentage of crystalline rock, bare rock and glacier. The conclusion of our research is that it is not straightforward to separate the effects of climate and catchment properties on drought, since they are interrelated. This is especially true for mountainous regions where temperature and precipitation are strongly dependent on altitude. We did however see that the duration of drought is more related to catchment storage (catchment properties) and the severity of drought (represented by the drought deficit) is more related to catchment wetness (climate). Van Loon, A.F., and Van Lanen, H.A.J.: A process-based typology of hydrological drought, Hydrology and Earth System Science, 16, p. 1915-1946, doi: 10.5194/hess-16-1915-2012, 2012

  2. Watershed scale spatial variability in dissolved and total organic and inorganic carbon in contrasting UK catchments

    NASA Astrophysics Data System (ADS)

    Cumberland, S.; Baker, A.; Hudson, N. J.

    2006-12-01

    ) Recent investigations into carbon fluxes in British rivers have focused on long term increases in DOC in rural and predominantly upland catchments. Our results suggest that research is needed into understanding long term variations in inorganic carbon concentration, as well as total (organic and inorganic) carbon fluxes from British rivers, to obtain total carbon loads. In particular, we provide evidence that DIC concentrations may be greater in urbanized catchments compared to equivalent non-urban catchments, with the implication that increasing urbanization in the future will see increases in riverine DIC and a decrease in the strength of any DOC DIC anti correlation. Further studies of urban catchment DIC sources, within stream processing, long term trends, and potential ecological impacts, are required.

  3. Influence of teleconnection on water quality in agricultural river catchments

    NASA Astrophysics Data System (ADS)

    Mellander, Per-Erik; Jordan, Phil; Shore, Mairead; McDonald, Noeleen; Shortle, Ger

    2015-04-01

    Influences such as weather, flow controls and lag time play an important role in the processes influencing the water quality of agricultural catchments. In particular weather signals need to be clearly considered when interpreting the effectiveness of current measures for reducing nitrogen (N) and phosphorus (P) losses from agricultural sources to water bodies. In north-western Europe weather patterns and trends are influenced by large-scale systems such as the North Atlantic Oscillation (NAO) and the position of the Gulf Stream, the latter expressed as the Gulf Stream North Wall index (GSNW index). Here we present five years of monthly data of nitrate-N concentration in stream water and groundwater (aggregated from sub-hourly monitoring in the stream outlet and monthly sampling in multilevel monitoring wells) from four agricultural catchments (ca. 10 km2) together with monitored weather parameters, long-term weather data and the GSNW index. The catchments are situated in Ireland on the Atlantic seaboard and are susceptible to sudden and seasonal shifts in oceanic climate patterns. Rain anomalies and soil moisture deficit dynamics were similar to the dynamics of the GSNW index. There were monitored changes in nitrate-N concentration in both groundwater and surface water with no apparent connection to agricultural management; instead such changes also appeared to follow the GSNW index. For example, in catchments with poorly drained soils and a 'flashy hydrology' there were seasonal dynamics in nitrate-N concentration that correlated with the seasonal dynamics of the GSNW index. In a groundwater driven catchment there was a consistent increase in nitrate-N concentration over the monitored period which may be the result of increasingly more recharge in summer and autumn (as indicated by more flux in the GSNW index). The results highlight that the position of the Gulf Stream may influence the nitrate-N concentration in groundwater and stream water and there is a risk

  4. Safety evaluation report related to the renewal of the operating license for the research reactor at North Carolina State University

    SciTech Connect

    1997-04-01

    This safety evaluation report (SER) summarizes the findings of a safety review conducted by the staff of the U.S. Nuclear Regulatory Commission (NRC), Office of Nuclear Reactor Regulation (NRR). The staff conducted this review in response to a timely application filed by North Carolina State University (the licensee or NCSU) for a 20-year renewal of Facility Operating License R-120 to continue to operate the NCSU PULSTAR research reactor. The facility is located in the Burlington Engineering Laboratory complex on the NCSU campus in Raleigh, North Carolina. In its safety review, the staff considered information submitted by the licensee (including past operating history recorded in the licensee`s annual reports to the NRC), as well as inspection reports prepared by NRC Region H personnel and first-hand observations. On the basis of this review, the staff concludes that NCSU can continue to operate the PULSTAR research reactor, in accordance with its application, without endangering the health and safety of the public. 16 refs., 31 figs., 7 tabs.

  5. The North American Fetal Therapy Network (NAFTNet): a new approach to collaborative research in fetal diagnosis and therapy.

    PubMed

    Johnson, Mark Paul

    2010-02-01

    In August 2004, the National Institutes of Health organized a 'Workshop on Fetal Therapy' to develop a plan for the maternal-fetal, surgical, and neonatal evaluation and treatment of pregnancies that might benefit from in-utero therapy. At the completion of the workshop several recommendations were made, foremost of which was the 'formation of a cooperative group of clinical investigators to help set a national agenda for research and clinical progress in the field of fetal therapy'. Somewhat by coincidence, a multidisciplinary 'Fetal Therapy Working Group' that had been formed earlier in the year was well-positioned to accept this national mandate and proposed development of a North American Fetal Therapy Network (NAFTNet) to foster collaborative research between active fetal diagnosis and treatment centers in both the USA and Canada, develop a peer review mechanism for study proposals, explore ways to centralize data collection and study development, and establish an educational agenda for medical professionals and the public as well as training of future leaders in the field. NAFTNet represents a new paradigm and approach to international collaborative research. Early success has resulted in the recognition of the power of collaborative research efforts in studying rare congenital anomalies and intervention strategies to improve outcomes and survivals in such limited populations. By abandoning 'competitive research' for a cooperative, collaborative environment of research partnership, NAFTNet strives to be more responsible and effective in using limited resources and improving care for pregnancies and children born with congenital anomalies. PMID:19556173

  6. Timber resource statistics for the north interior resource area of California. Forest Service research bulletin

    SciTech Connect

    Waddell, K.L.; Bassett, P.M.

    1997-03-01

    This report is a summary of timber resource statistics for the North Interior Resource Area of California, which includes Lassen, Modoc, Shasta, Siskiyou, and Trinity Counties. Data were collected as part of a statewide multiresource inventory. The inventory sampled private and public lands except reserved areas and National Forests. The National Forest System provided data from regional inventories of the Lassen, Mendocino, Modoc, Six Rivers, Plumas, Shasta-Trinity, Rogue River, and Toiyabe National Forests. Area information for parks and other reserves was obtained directly from the organizations managing these areas. Statistical tables summarize all ownerships and provide estimates of land area, timber volume, growth, mortality , and harvest. Estimates of periodic change of timberland area and timber volume are presented for all ownerships outside National Forests.

  7. Coevolution of volcanic catchments in Japan

    NASA Astrophysics Data System (ADS)

    Yoshida, Takeo; Troch, Peter A.

    2016-03-01

    Present-day landscapes have evolved over time through interactions between the prevailing climates and geological settings. Understanding the linkage between spatial patterns of landforms, soils, and vegetation in landscapes and their hydrological response is critical to make quantitative predictions in ungaged basins. Catchment coevolution is a theoretical framework that seeks to formulate hypotheses about the mechanisms and conditions that determine the historical development of catchments and how such evolution affects their hydrological response. In this study, we selected 14 volcanic catchments of different ages (from 0.225 to 82.2 Ma) in Japan. We derived indices of landscape properties (drainage density and slope-area relationship) as well as hydrological response (annual water balance, baseflow index, and flow-duration curves) and examined their relation with catchment age and climate (through the aridity index). We found a significant correlation between drainage density and baseflow index with age, but not with climate. The intra-annual flow variability was also significantly related to catchments age. Younger catchments tended to have lower peak flows and higher low flows, while older catchments exhibited more flashy runoff. The decrease in baseflow with catchment age is consistent with the existing hypothesis that in volcanic landscapes the major flow pathways change over time from deep groundwater flow to shallow subsurface flow. The drainage density of our catchments decreased with age, contrary to previous findings in a set of similar, but younger volcanic catchments in the Oregon Cascades, in which drainage density increased with age. In that case, older catchments were thought to show more landscape incision due to increasing near-surface lateral flow paths. Our results suggests two competing hypotheses on the evolution of drainage density in mature catchments. One is that as catchments continue to age, the hydrologically active channels retreat

  8. From Heart Health to Brain Health: Legacy of the North Karelia Project for Dementia Research.

    PubMed

    Kivipelto, Miia; Ngandu, Tiia

    2016-06-01

    Cognitive impairment is very common in advanced age, with dementia representing the main cause of disability in older adults. Over the past 20 years, several modifiable risk factors have been identified for dementia and Alzheimer's disease (AD), and many of them are shared with cardiovascular diseases. Given that the pathologic changes leading to dementia may start decades before dementia is diagnosed, it is crucial to adopt a life course approach when investigating risk factors for dementia. The CAIDE (Cardiovascular Risk Factors, Aging and Dementia) study is one of the first and still very few existing observational studies to have investigated the role of midlife risk factors for the subsequent development of dementia and AD in late life. The CAIDE study is built on the North Karelia Project, enabling risk factor assessment 20 to 30 years before the dementia diagnosis. The CAIDE study has revealed that late-life dementia and AD are heterogeneous and multifactorial disorders, suggesting that multidomain interventions targeting several risk factors simultaneously may be needed for optimal preventive effects. The FINGER (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability) study is the first large long-term multidomain lifestyle intervention showing effect on prevention of cognitive impairment in at-risk elderly people. The study is conducted within the existing framework and builds on multidisciplinary prevention expertise following the North Karelia Project and CAIDE study. The FINGER study will, together with the ongoing multinational preventive initiatives, pave the way for pragmatic prevention programs and integrated interventions to facilitate healthy brain aging. This paper summarizes major findings on risk and protective factors for dementia and AD, and reviews key aspects and future directions in preventative strategies. PMID:27242093

  9. Recent research on the hydrodynamics of the Sacramento - San Joaquin River Delta and north San Francisco Bay

    USGS Publications Warehouse

    Burau, J.R.; Monismith, S.G.; Stacey, M.T.; Oltmann, R.N.; Lacy, J.R.; Schoellhamer, D.H.

    1999-01-01

    This article presents an overview of recent findings from hydrodynamic research on circulation and mixing in the Sacramento-San Joaquin Delta (Delta) (Figure 1) and North San Francisco Bay (North Bay) (Figure 2). For the purposes of this article, North Bay includes San Pablo Bay, Carquinez Strait, and Suisun Bay. The findings presented are those gained from field studies carried out by the U.S. Geological Survey (USGS), as part of the Interagency Ecological Program (IEP), and Stanford University beginning about 1993. The premise behind these studies was that a basic understanding of circulation and mixing patterns in the Bay and Delta is an essential part of understanding how biota and water quality are affected by natural hydrologic variability, water appropriation, and development activities. Data collected for the field studies described in this article have significantly improved our understanding of Bay and Delta hydrodynamics. Measured flows ,in the Delta have provided valuable information on how water moves through the Delta's network of channels and how export pumping affects flows. Studies of the shallows and shallow-channel exchange processes conducted in Honker Bay have shown that the water residence time in Honker Bay is much shorter than previously reported (on the order of hours to several tidal cycles instead ofweeks). Suisun Bay studies have provided data on hydrodynamic transport and accumulation mechanisms that operate primarily in the channels. The Suisun Bay studies have caused us to revise our understanding of residual circulation in the channels of North Bay and of "entrapment" mechanisms in the low salinity zone. Finally, detailed tidal and residual (tidally averaged) time-scale studies of the mechanisms that control gravitational circulation in the estuary show that density-driven transport in the channels is governed by turbulence time-scale (seconds) interactions between the mean flow and stratification. The hydrodynamic research

  10. Changes in catchment hydrology in relation to vegetation recovery: a comparative modelling experiment

    NASA Astrophysics Data System (ADS)

    Lana-Renault, Noemí; Karssenberg, Derek; Latron, Jérôme; Serrano, Mā Pilar; Regüés, David; Bierkens, Marc F. P.

    2010-05-01

    Mediterranean mountains have been largely affected by land abandonment and subsequent vegetation recovery, with a general expansion of shrubs and forests. Such a large scale land-cover change has modified the hydrological behavior of these areas, with significant impact on runoff production. Forecasting the trend of water resources under future re-vegetation scenarios is of paramount importance in Mediterranean basins, where water management relies on runoff generated in these areas. With this purpose, a modelling experiment was designed based on the information collected in two neighbouring research catchments with a different history of land use in the central Spanish Pyrenees. One (2.84 km2) is an abandoned agricultural catchment subjected to plant colonization and at present mainly covered by shrubs. The other (0.92 km2) is a catchment covered by dense natural forest, representative of undisturbed environments. Here we present the results of the analysis of the hydrological differences between the two catchments, and a description of the approach and results of the modelling experiment. In a statistical analysis of the field data, significant differences were observed in the streamflow response of the two catchments. The forested catchment recorded fewer floods per year compared to the old agricultural catchment, and its hydrological response was characterised by a marked seasonality, with autumn and spring as the only high flow periods. Stormflow was generally higher in the old agricultural catchment, especially for low to intermediate size events; only for large events the stormflow in the forested catchment was sometimes greater. Under drier conditions, the relative differences in the stormflow between the two catchments tended to increase whereas under wet conditions they tended to be similar. The forested catchment always reacted more slowly to rainfall, with lower peakflows (generally one order of magnitude lower) and longer recession limbs. The modelling

  11. Using stable isotopes to estimate and compare mean residence times in contrasting geologic catchments (Attert River, NW Luxembourg)

    NASA Astrophysics Data System (ADS)

    Martínez-Carreras, N.; Fenicia, F.; Frentress, J.; Wrede, S.; Pfister, L.

    2012-04-01

    In recent years, stable isotopes have been increasingly used to characterize important aspects of catchment hydrological functioning, such as water storage dynamics, flow pathways and water sources. These characteristics are often synthesized by the Mean Residence Time (MRT), which is a simple catchment descriptor that employ the relation of distinct stable isotopic signatures in the rainfall input and streamflow output of a catchment that are significantly dampened through sub-surface propagation. In this preliminary study, MRT was estimated in the Attert River catchment (NW Luxembourg), where previous studies have shown that lithology exerts a major control on runoff generation. The Attert catchment lies at the transition zone of contrasting bedrock lithology: the Northern part is characterized by Devonian schist of the Ardennes massif, while sedimentary deposits of sandstone and marls dominate in the south of the catchment. As a consequence of differing lithologic characteristics, hydrological processes change across scales. The schistose catchments exhibit a delayed shallow groundwater component, sandstone catchments have slow-responding year-round groundwater component, whereas flashy runoff regimes prevails in the marly catchments. Under these circumstances, the MRTs are expected to vary significantly according to lithology, and provide additional understanding in internal catchment processes and their scale dependencies. In order to test this, bi-weekly monitoring of rainfall and discharge stable water isotope composition (oxygen-18 and deuterium) has been carried out since 2007 in 10 nested sub-catchments ranging in size from 0.4 to 247 km2 in the Attert catchment. MRT was estimated using different lumped convolution integral models and sine wave functions with varying transit times distributions (TTDs). TTDs were evaluated through calibration. Further research efforts will deal with the application of conceptual models to simulate and compare TTD, using

  12. Impacts of climate and land use changes on regional nutrient export in the South Saskatchewan River catchment

    NASA Astrophysics Data System (ADS)

    Morales-Marin, L. A.; Wheater, H. S.; Lindenschmidt, K. E.

    2015-12-01

    Climate and land use changes modify the physical functioning of river catchments and, in particular, influence the transport of nutrients from land to water. In large-scale catchments, where a variety of climates, topographies, soil types and land uses co-exist to form a highly heterogeneous environment, a more complex nutrient dynamic is imposed by climate and land use changes. This is the case of the South Saskatchewan River (SSR) that, along with the North Saskatchewan River, forms the largest river system in western Canada. In the past years changes in the land use and new industrial developments in the SSR area have heightened serious concerns about the future of water quality in the catchment and downstream waters. Agricultural activities have increased the supply of manure and fertilizer for cropping. Oil and gas exploitation has also increased the risk of surface water and groundwater contamination. The rapid population growth not only leads to increments in water consumption and wastewater, but in the construction of roads, railways and the expansion of new urban developments that impose hydraulic controls on the catchment hydrology and therefore the sediment and nutrient transport. Consequences of the actual anthropogenic changes have been notorious in reservoirs where algal blooms and signs of eutrophication have become common during certain times of the year. Although environmental agencies are constantly improving the mechanisms to reduce nutrient export into the river and ensure safe water quality standards, further research is needed in order to identify major nutrient sources and quantify nutrient export and also, to assess how nutrients are going to vary as a result of future climate and land use change scenarios. The SPAtially Referenced Regression On Watershed (SPARROW) model is therefore implemented to assess water quality regionally, in order to describe spatial and temporal patterns to identify those factors and processes that affect water

  13. Understanding fine sediment and phosphorous delivery in upland catchments

    NASA Astrophysics Data System (ADS)

    Perks, M. T.; Reaney, S. M.

    2013-12-01

    The uplands of UK are heavily impacted by land management including; farming and forestry operations, moorland burning, peat extraction, metal mining, artificial drainage and channelisation. It has been demonstrated that such land management activity may modify hillslope processes, resulting in enhanced runoff generation and changing the spatial distribution and magnitude of erosion. Resultantly, few upland river systems of the UK are operating in a natural state, with land management activity often resulting in increased fluxes of suspended sediment (< 2 mm) and associated pollutants (such as phosphorous). Most recent Environment Agency (EA) data reveals that 60% of monitored water bodies within upland areas of the UK are currently at risk of failing the Water Framework Directive (WFD) due to poor ecological status. In order to prevent the continual degradation of many upland catchments, riverine systems and their diverse ecosystems, a range of measures to control diffuse pollution will need to be implemented. Future mitigation options and measures in the UK may be tested and targeted through the EA's catchment pilot scheme; DEFRA's Demonstration Test Catchment (DTC) programmes and through the catchment restoration fund. However, restoring the physical and biological processes of past conditions in inherently sensitive upland environments is extremely challenging requiring the development of a solid evidence base to determine the effectiveness of resource allocation and to enable reliable and transparent decisions to be made about future catchment operations. Such evidence is rarely collected, with post-implementation assessments often neglected. This paper presents research conducted in the Morland sub-catchment of the River Eden within Cumbria; UK. 80% of this headwater catchment is in upland areas and is dominated by improved grassland and rough grazing. The catchment is heavily instrumented with a range of hydro-meteorological equipment. A high-tech monitoring

  14. Remote assessment of instantaneous changes in water chemistry after liming in a Nova Scotia catchment

    NASA Astrophysics Data System (ADS)

    Angelidis, Christine

    2013-04-01

    Remote assessment of instantaneous changes in water chemistry after liming in a Nova Scotia catchment ANGELIDIS, C.1, STERLING, S.1, BREEN, A.2, BIAGI, K.1., and CLAIR, T.A.1 1Dalhousie University, christine.angelidis@dal.ca, 2Bluenose Coastal Action Foundation, andrew@coastalaction.org Southwestern Nova Scotia has some of the most acidic freshwaters in North America due to its location downwind of the major emission sources in eastern Canada and the US and due to a resistant geology which offers little acid buffering capacity (Clair et al. 2007). Because of the poor buffering and regionally high runoff values, hydrological events such as snowmelt and rain storms are frequent and can cause sudden changes in water chemistry which can have devastating effects on freshwater biota due to increases in acidity and metals (Dennis and Clair in press). Clair et al. (2001) have estimated the potential frequency of acidic episodes in this region based on a number of hydrological factors, though the technology available at the time to monitor short-term changes was not dependable. Recent advances in equipment have made the assessment of the frequency and severity of acidic episodes easier and more accurate, allowing better interpretation and prediction of hydrogeochemical changes with variations in weather and deposition patterns. Here we take advantage of these recent advances to monitor water chemistry in an experimental catchment, and explore the response to catchment liming. Catchment liming is one way of mitigating the effects of acid deposition in sensitive areas. We limed a 50 ha catchment at a rate of 5 t/ha in the Gold River watershed of southwest Nova Scotia to examine the interactions between application of lime with the geological and climatological conditions of this region and acid episode frequency. In order to assess changes of episode frequency caused by liming, we established two mobile environmental monitoring platforms in the catchment: a control site

  15. Qualitative Research, Semiotics, North Beach, South of Markey, Jack London, and the Grateful Dead.

    ERIC Educational Resources Information Center

    Shank, Gary

    1999-01-01

    Looks at educational research from a macro perspective, advocating semiotics as the foundation for qualitative research in education. Presents myths and disputations and an open-ended conclusion via the kaleidoscopic interpretations of Jack London, Phil Dick, Jack Kerouac, the Grateful Dead, and an assortment of street characters. (Author/VWL)

  16. An Investigation of Distance Education in North American Research Literature Using Co-Word Analysis

    ERIC Educational Resources Information Center

    Ritzhaupt, Albert D.; Stewart, Michelle; Smith, Patryce; Barron, Ann E.

    2010-01-01

    The field of distance education is composed of a multiplicity of topics leading to a vast array of research literature. However, the research does not provide a chronological picture of the topics it addresses, making it difficult to develop an overview of the evolution and trends in the literature. To address this issue, a co-word analysis was…

  17. The future of cardiovascular clinical research in North America and beyond-addressing challenges and leveraging opportunities through unique academic and grassroots collaborations.

    PubMed

    Roe, Matthew T; Mahaffey, Kenneth W; Ezekowitz, Justin A; Alexander, John H; Goodman, Shaun G; Hernandez, Adrian; Temple, Tracy; Berdan, Lisa; Califf, Robert M; Harrington, Robert A; Peterson, Eric D; Armstrong, Paul W

    2015-06-01

    Recent developments have highlighted the challenges facing cardiovascular clinical research in global contemporary practice, particularly in North America, including shifting priorities for drug development targets, increasing regulatory requirements, and expensive operational approaches for conducting randomized clinical trials. Nonetheless, emerging trends such as the consolidation of practices and hospitals into integrated health systems, the integration of electronic health records from thousands of practices into large data repositories to support prospective research studies, and streamlined operational approaches such as registry-based trials and risk-based monitoring have created numerous opportunities to disrupt the clinical research paradigm. Within this context, academic research organizations around the globe, particularly a strengthened collaboration of 3 established academic research organizations in North America, are uniquely positioned to promote and develop grassroots collaborations across all types of clinical practices, to delineate successful solutions to obstacles that limit clinical research initiatives, and to guide the future of cardiovascular research in the global research environment. PMID:26027610

  18. Opinions of fisheries researchers, managers, and anglers towards recreational fishing issues: an exploratory analysis for North America

    SciTech Connect

    Hasler, Caleb T.; Colotelo, Alison HA; Rapp, Tobias; Jamieson, Elizabeth; Bellehumeur, Karyne; Arlinghaus, Robert; Cooke, Steven J.

    2011-05-02

    There is a need to better understand the perspectives of various recreational fishing stakeholder groups regarding key issues related to fisheries sustainability. To provide a first snapshot and to inform future human dimension studies in this area, we distributed a Web-based open-access survey to fisheries researchers, fisheries managers, and anglers in North America. Attitudes of these respondents towards issues such as overharvest, impacts of catch and release, recreational fisheries management, and research priorities for the future were assessed. We found similar opinions and perspectives by the responding recreational anglers, managers,and researchers on a number of issues, such as the perceived impact of commercial fishing contributing to fish stock declines, the perceived importance of using and promoting gear that minimizes stress and injury to individual fish when fish are to be released, and the belief that conflicts among stakeholders is growing as is the global anti-fishing movement based on animal rights thinking. Differences among responding groups included that researchers tended to be more concerned than anglers and managers with the potential of recreational angling contributing to fish stock declines. Responding anglers were also less content with their involvement in the fisheries management process than were responding managers and researchers, and these anglers also indicated a greater desire for more human dimensions research on understanding angler attitudes and behavior than was evident for responding managers and researchers. This preliminary survey revealed some variation in attitudes among recreational fisheries stakeholders. However, due to lack of random sampling, the study results cannot be extrapolated to the population level. We nevertheless conclude that improved communication and better understanding about the different perspectives among fisheries researchers, managers, and anglers and intrasectorally among different angling

  19. Frito-Lay North America/NREL CRADA: Cooperative Research and Development Final Report, CRADA Number CRD-06-176

    SciTech Connect

    Walker, A.

    2013-06-01

    Frito Lay North America (FLNA) requires technical assistance for the evaluation and implementation of renewable energy and energy efficiency projects in production facilities and distribution centers across North America. Services provided by NREL do not compete with those available in the private sector, but rather provide FLNA with expertise to create opportunities for the private sector renewable/efficiency industries and to inform FLNA decision making regarding cost-effective projects. Services include: identifying the most cost-effective project locations based on renewable energy resource data, utility data, incentives and other parameters affecting projects; assistance with feasibility studies; procurement specifications; design reviews; and other services to support FNLA in improving resource efficiency at facilities. This Cooperative Research and Development Agreement (CRADA) establishes the terms and conditions under which FLNA may access capabilities unique to the laboratory and required by FLNA. Each subsequent task issued under this umbrella agreement would include a scope-of-work, budget, schedule, and provisions for intellectual property specific to that task.

  20. Research into the functional components and antioxidant activities of North China rice wine (Ji Mo Lao Jiu)

    PubMed Central

    He, Shuai; Mao, Xiangzhao; Liu, Pei; Lin, Hong; Du, Zuyuan; Lv, Ning; Han, Jichen; Qiu, Cuifang

    2013-01-01

    Over the last decade, considerable experimental evidence has supported the view that grape wine and South China rice wine are rich in diverse nutrients and have powerful antioxidant activity. However, little research has been carried out for North China rice wine, of which Ji Mo Lao Jiu (JMLJ) is the outstanding representative. In this study, the functional components and antioxidant activity of JMLJ were investigated. Twenty-eight free amino acids were found in JMLJ, much more than that previously reported in other Chinese rice wines (16–21). Functional oligosaccharides (5290.222 mg/L), total phenols (722.431 ± 10.970 mg/L), and mineral elements (9) were rich in JMLJ. When compared with synthetic antioxidants, such as butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT), JMLJ showed effective 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging and reducing capacity. The results of this study lay the foundation for promoting the utilization of JMLJ and the development of North China rice wine in the food industry. PMID:24804035

  1. The Evaluation of Educational Programmes: Methods, Uses and Benefits. Part A, Volume 24. Report of the Educational Research Workshop (North Berwick, Scotland, November 22-25, 1988).

    ERIC Educational Resources Information Center

    Scottish Council for Research in Education.

    An introductory report, six commissioned papers, and four selected background reports presented at the North Berwick Workshop, one of a series of educational research meetings sponsored by the Council of Europe, are provided. The Workshop brought together research workers and educational administrators from different countries to: review…

  2. Nitrogen Concentrations and Exports in Baseflow and Stormflow from Three Small Urban Catchments in Central Florida

    NASA Astrophysics Data System (ADS)

    Luo, J.; Hochmuth, G.; Clark, M. W.

    2014-12-01

    Export of nitrogen from different watersheds across the United States is receiving increasing attention due to the impairment of water quality in receiving water bodies. Researchers have indicated that different land uses exerted a substantial influence on the water quality. Nitrogen loadings on the watershed scale are being studied in many large ecosystems, such as the Baltimore Ecosystem and Arizona Ecosystem, but only a few focuses in a smaller scale such as catchment scale. Characterization of the land use in catchment scale can better explain the observed environmental phenomena under the watershed scale and enrich the related watershed studies. Nitrogen fluxes have been studied at Lake Alice watershed in Gainesville, Florida with a focus on the rarely studied catchments such as sports fields with intensive fertilization management (SFC), urban area with reclaimed water irrigation (RWC) and urban area without irrigation (CC). The entire study started from May 2013. Discharge was monitored in the three catchments by transducers every 5 minutes. Regular biweekly grab samples in the three catchments were used to estimate the baseflow N loads, composite samples in 13 storms were collected to estimate the stormflow N loads. The results showed that in the baseflow, the average NO3-N concentration in SFC was 12.19 mg/l, which was significantly different from the urban catchments. Also there was a significant difference between the NO3-N concentrations in RWC (1.17 mg/l on average) and CC (0.60 mg/l on average). A separate log-log relationship was developed between discharge and N loads to estimate the baseflow N loads and stormflow N loads. It showed that baseflow contributed more N loads than stormflow in the three catchments in the annual N load. In conclusion, the recreational catchment received the greatest N load compared to the other catchments, so it should be the priority catchment when it comes to adopting nutrient management practices in the Lake Alice

  3. Fieldwork challenges: lessons learned from a north-south public health research partnership.

    PubMed

    Casale, Marisa A J; Flicker, Sarah; Nixon, Stephanie A

    2011-09-01

    The value of collaborative international research in addressing global public health challenges is increasingly recognized. However, little has been written about lessons learned regarding fieldwork to help guide future collaborative efforts. Through a research partnership between two Northern universities, one Southern university, and a Southern faith-based organization, we evaluated a school-based HIV prevention intervention with South African adolescents. In this article, we highlight the seven key fieldwork-related challenges experienced and identify the lessons learned. The underlying theme is that of reconciling a structured and reasoned "desk" planning process with the more fluid and unpredictable reality of conducting fieldwork. This concern is particularly significant in resource-deprived environments and/or contexts that are less familiar to Northern partners. Fieldwork is unpredictable, but obstacles can be minimized through meaningful participation in both planning and field research. Sharing practical lessons from the field can prove a useful resource for both researchers and practitioners. PMID:21422255

  4. Institutional Research and Planning in the Next Decade. Proceedings from the Annual Conference of the North East Association for Institutional Research (10th, Hershey, Pennsylvania, October 16-18, 1983). Tenth Anniversary Issue.

    ERIC Educational Resources Information Center

    North East Association for Institutional Research.

    Proceedings of the 1983 conference of the North East Association for Institutional Research are presented. The contribution of institutional research to university decision making and the topics of student outcomes assessment, retention/attrition studies, marketing/market research, departmental studies, computer and technological applications, and…

  5. Assessment of surface water resources availability using catchment modeling and the results of tracer studies in the meso-scale Migina Catchment, Rwanda

    NASA Astrophysics Data System (ADS)

    Munyaneza, O.; Mukubwa, A.; Maskey, S.; Wenninger, J.; Uhlenbrook, S.

    2013-12-01

    In the last couple of years, different hydrological research projects were undertaken in the Migina catchment (243.2 km2), a tributary of the Kagera river in Southern Rwanda. These projects were aimed to understand hydrological processes of the catchment using analytical and experimental approaches and to build a pilot case whose experience can be extended to other catchments in Rwanda. In the present study, we developed a hydrological model of the catchment, which can be used to inform water resources planning and decision making. The semi-distributed hydrological model HEC-HMS (version 3.5) was used with its soil moisture accounting, unit hydrograph, liner reservoir (for base flow) and Muskingum-Cunge (river routing) methods. We used rainfall data from 12 stations and streamflow data from 5 stations, which were collected as part of this study over a period of two years (May 2009 and June 2011). The catchment was divided into five sub-catchments each represented by one of the five observed streamflow gauges. The model parameters were calibrated separately for each sub-catchment using the observed streamflow data. Calibration results obtained were found acceptable at four stations with a Nash-Sutcliffe Model Efficiency of 0.65 on daily runoff at the catchment outlet. Due to the lack of sufficient and reliable data for longer periods, a model validation (split sample test) was not undertaken. However, we used results from tracer based hydrograph separation from a previous study to compare our model results in terms of the runoff components. It was shown that the model performed well in simulating the total flow volume, peak flow and timing as well as the portion of direct runoff and base flow. We observed considerable disparities in the parameters (e.g. groundwater storage) and runoff components across the five sub-catchments, that provided insights into the different hydrological processes at sub-catchment scale. We conclude that such disparities justify the need

  6. A small Internet controllable observatory for research and education at the University of North Dakota

    NASA Astrophysics Data System (ADS)

    Hardersen, P. S.; de Silva, S.; Reddy, V.; Cui, P.; Kumar, S.; Gaffey, M. J.

    2006-06-01

    One of the challenges in astronomy education today is to introduce college students to the real-world practice and science of observational astronomy. Along with a good theoretical background, college students can gain an earlier, deeper understanding of the astronomy profession through direct observational and data reduction experience. However, building and managing a modest observatory is still too costly for many colleges and universities. Fortunately, advances in commercial astronomical hardware and software now allow universities to build and operate small Internet controllable observatories for a modest investment. The advantages of an Internet observatory include: 1) remote operation from a comfortable location, 2) immediate data access, 3) telescope control via a web browser, and 4) allowing both on-campus and distance education students the ability to conduct a variety of observing projects. Internet capabilities vastly expand the number of students who will be able to use the observatory, thus exposing them to astronomy as a science and as a potential career. In September 2005, the University of North Dakota (UND) Department of Space Studies began operating a small, recently renovated Internet controllable observatory. Housed within a roll-off roof 10 miles west of UND, the observatory includes a Meade 16-inch, f/10 Schmidt-Cassegrain telescope, an SBIG STL-6303e CCD with broadband filters, ACP observatory control software, focuser, and associated equipment. The observatory cost \\25,000 to build in 1996; 2005 renovation costs total \\28,000. An observatory operator prepares the telescope for use each night. Through remote operation, the roof is opened and the telescope/CCD power is turned on. The telescope is then aligned and focused before allowing students to access the observatory. Students communicate with the observatory operator via an online chat room and via telephone, if necessary, to answer questions and resolve any problems. Additional

  7. Atmospheric Electric Field measurements at Eastern North Atlantic ARM Climate Research Facility: Global Electric Circuit Evolution

    NASA Astrophysics Data System (ADS)

    Lopes, Francisco; Silva, Hugo; Nitschke, Kim; Azevedo, Eduardo

    2016-04-01

    The Eastern North Atlantic (ENA) facility of the ARM programme (established an supported by the U.S. Department of Energy with the collaboration of the local government and University of the Azores), is located at Graciosa Island of the Azores Archipelago (39° N; 28° W). It constitutes a strategic observatory for Atmospheric Electricity since it is located in the Atlantic Ocean basin exposed to clean marine aerosol conditions which reduces the well known spectral signature of atmospheric pollution and enables the study of the so called Global Electrical Circuit (GEC). First evidences of the existence of a GEC affecting the Earth's Electric Environment has retrieved by the Carnegie cruise expedition, in what became known as the Carnegie Curve. Those measurements were made in the Ocean in several campaigns and the present studies aims at reconsidering measurements in similar conditions but in a long-term basis, at least 5 years. This will contribute to the understanding of the long-term evolution of the Ionospheric Potential (IP). In literature there is theoretical evidence that it is decreasing IP in strength, but that conjecture is still lacking valid experimental evidence. Moreover, to clearly identify the GEC signal two effects must be taken into account: the effect of surface radon gas variation, because the Azores Archipelago is a seismic active region the possible influence of Earthquakes cannot be discarded easily; the effect of short-term solar activity on the Atmospheric Electricity modulation, solar flares emitting solar particles (e.g., solar energetic protons) need to be considered in this study.

  8. Hydrologic regime alteration of a Mediterranean catchment under climate change projection

    NASA Astrophysics Data System (ADS)

    Sellami, Haykel; Benabdallah, Sihem; La Jeunesse, Isabelle; Herrmann, Frank; Vanclooster, Marnik

    2014-05-01

    Most of the climate models projections for the Mediterranean basin have showed that the region will likely to experience a general tendency towards drier climate conditions with decreases in total precipitation, increases in temperature, alterations in the rainfall extreme events and droughts frequency (IPCC, 2007; Giorgi and Lionello, 2008; López-Moreno et al., 2011). The region is already suffering from water resources scarcity and vulnerability which are expected to amplify in the next century (Ludwig et al., 2011; Schneider et al., 2013). Therefore, assessing the impact of climate change on the hydrologic regime of Mediterranean catchments is with a major concern not only to scientist but also to water resources policy makers and general public. However, most of the climate change impact studies focus on the flow regime on global or regional scale rather than on the catchment scale which is more useful and more appropriate to guide practical mitigation and adaptation policy. This is because hydro-climate modeling at the local scale is confronted to the variability in climate, topography, geology, lack of observations and anthropogenic activities within the catchment. Furthermore, it is well recognized that hydrological and climate models forecasts are always affected with uncertainty making the assessment of climate change impact on Mediterranean catchment hydrology more challenging. This work aims to assess the impact of climate change on a Mediterranean catchment located in North Africa (the Chiba catchment in northeast Tunisia) through a conjunctive use of physically based hydrological model (SWAT) driven with four climate models*. Quantification of the impact of climate change has been conducted by means of the Indicators of Hydrologic Alteration (Richter et al., 1996) which are also ecologically meaningful. By comparing changes in these indicators in the reference period (1971-2000) to the projected ones in the future (2041-2070), it was possible to draw

  9. A Catchment-Based Land Surface Model for GCMs and the Framework for its Evaluation

    NASA Technical Reports Server (NTRS)

    Ducharen, A.; Koster, R. D.; Suarez, M. J.; Kumar, P.

    1998-01-01

    A new GCM-scale land surface modeling strategy that explicitly accounts for subgrid soil moisture variability and its effects on evaporation and runoff is now being explored. In a break from traditional modeling strategies, the continental surface is disaggregated into a mosaic of hydrological catchments, with boundaries that are not dictated by a regular grid but by topography. Within each catchment, the variability of soil moisture is deduced from TOP-MODEL equations with a special treatment of the unsaturated zone. This paper gives an overview of this new approach and presents the general framework for its off-line evaluation over North-America.

  10. North-South Partnership in Space Research and Application: Space Research Center at Minufiyia University, Egypt, as Case Study

    NASA Astrophysics Data System (ADS)

    Shaltout, M.

    With the starting the year 2002 the Minufiyia University Council taked an Issue by construction Space Research Center, as a first Center for Space Research in the Egyptian Universities (20 Universities), as a part from the Desert Environment Research Institute for temporal time, then after the growth, it will be independent center. The green area of Egypt (Nile Valley and Delta) are 4% only from the total area of Egypt, the remain 96% is desert area. The most useful thing is to study the desert from space. For that the suggested projects to be performed in this new center are: 1.Monitoring the storage tanks of the underground water in the Egyptian Desert (Sahara) by artificial satellites as GRACE of NASA and DLR. 2.Building 32 meter Radio telescope at Abu-Simbel in the South of Egypt as part of the European VLBI network (EVN) to cover the gab between the radio telescope in the western Europe and the radio telescope at Hartebessthock in South Africa. The cooperation of International interested institutions is being explored for this important project of Egypt. 3.Solar activity and the climatic changes through the 21st century as clarified by global solar radiation data at Khargha Oases at the western desert of Egypt. 4.Testing of the Martian exploration instruments for 2003 and 2005 space trips to Mars in the western desert of Egypt, as it is the driest area in the worl d, where are similarity between the dry atmosphere of Sahara and the atmosphere of Mars, also in the soil, and dry valleys. In collaboration with NASA and ESA. 5.Studding the eastern structure, due to meteoric impact in the western desert of Egypt since 28 Million years. Also, studding the meteors chemistry, for meteors found in the Egyptian desert, and the origin of life as meteor (Nachlet) in collaboration with NASA and ESA. Solar energy and humidity distribution over Sahara from artificial Satellite Meteostat observations.

  11. How tritium illuminates catchment structure

    NASA Astrophysics Data System (ADS)

    Stewart, M.; Morgenstern, U.; McDonnell, J.

    2012-04-01

    Streams contain water which has taken widely-varying times to pass through catchments, and the distribution of ages is likely to change with the flow. Part of the water has 'runoff' straight to the stream with little delay, other parts are more delayed and some has taken years (in some cases decades) to traverse the deeper regolith or bedrock of the catchment. This work aims to establish the significance of the last component, which is important because it can cause catchments to have long memories of contaminant inputs (e.g. nitrate). Results of tritium studies on streams world-wide were accessed from the scientific literature. Most of the studies assumed that there were just two age-components present in the streams (i.e. young and old). The mean ages and proportions of the components were found by fitting simulations to tritium data. It was found that the old component in streams was substantial (average was 50% of the annual runoff) and had considerable age (average mean age was 10 years) (Stewart et al., 2010). Use of oxygen-18 or chloride variations to estimate streamflow mean age usually does not reveal the age or size of this old component, because these methods cannot detect water older than about four years. Consequently, the use of tritium has shown that substantial parts of streamflow in headwater catchments are older than expected, and that deep groundwater plays an active and sometimes even a dominant role in runoff generation. Difficulties with interpretation of tritium in streams in recent years due to interference from tritium due to nuclear weapons testing are becoming less serious, because very accurate tritium measurements can be made and there is now little bomb-tritium remaining in the atmosphere. Mean ages can often be estimated from single tritium measurements in the Southern Hemisphere, because there was much less bomb-tritium in the atmosphere. This may also be possible for some locations in the Northern Hemisphere. Age determination on

  12. River nutrient loads and catchment size

    USGS Publications Warehouse

    Smith, S.V.; Swaney, D.P.; Buddemeier, R.W.; Scarsbrook, M.R.; Weatherhead, M.A.; Humborg, Christoph; Eriksson, H.; Hannerz, F.

    2005-01-01

    We have used a total of 496 sample sites to calibrate a simple regression model for calculating dissolved inorganic nutrient fluxes via runoff to the ocean. The regression uses the logarithms of runoff and human population as the independent variables and estimates the logarithms of dissolved inorganic nitrogen and phosphorus loading with R 2 values near 0.8. This predictive capability is about the same as has been derived for total nutrient loading with process-based models requiring more detailed information on independent variables. We conclude that population and runoff are robust proxies for the more detailed application, landscape modification, and in-stream processing estimated by more process-based models. The regression model has then been applied to a demonstration data set of 1353 river catchments draining to the sea from the North American continent south of the Canadian border. The geographic extents of these basins were extracted from a 1-km digital elevation model for North America, and both runoff and population were estimated for each basin. Most of the basins (72% of the total) are smaller than 103 km2, and both runoff and population density are higher and more variable among small basins than among larger ones.While total load to the ocean can probably be adequately estimated from large systems only, analysis of the geographic distribution of nutrient loading requires consideration of the small basins, which can exhibit significant hydrologic and demographic heterogeneity between systems over their range even within the same geographic region. High-resolution regional and local analysis is necessary for environmental assessment and management. ?? Springer 2005.

  13. Hydrological response of a small catchment burned by experimental fire

    NASA Astrophysics Data System (ADS)

    Stoof, C. R.; Vervoort, R. W.; Iwema, J.; van den Elsen, E.; Ferreira, A. J. D.; Ritsema, C. J.

    2012-02-01

    Fire can considerably change hydrological processes, increasing the risk of extreme flooding and erosion events. Although hydrological processes are largely affected by scale, catchment-scale studies on the hydrological impact of fire in Europe are scarce, and nested approaches are rarely used. We performed a catchment-scale experimental fire to improve insight into the drivers of fire impact on hydrology. In north-central Portugal, rainfall, canopy interception, streamflow and soil moisture were monitored in small shrub-covered paired catchments pre- and post-fire. The shrub cover was medium dense to dense (44 to 84%) and pre-fire canopy interception was on average 48.7% of total rainfall. Fire increased streamflow volumes 1.6 times more than predicted, resulting in increased runoff coefficients and changed rainfall-streamflow relationships - although the increase in streamflow per unit rainfall was only significant at the subcatchment-scale. Fire also fastened the response of topsoil moisture to rainfall from 2.7 to 2.1 h (p = 0.058), and caused more rapid drying of topsoils after rain events. Since soil physical changes due to fire were not apparent, we suggest that changes resulting from vegetation removal played an important role in increasing streamflow after fire. Results stress that fire impact on hydrology is largely affected by scale, highlight the hydrological impact of fire on small scales, and emphasize the risk of overestimating fire impact when upscaling plot-scale studies to the catchment-scale. Finally, they increase understanding of the processes contributing to post-fire flooding and erosion events.

  14. Signature Concepts of Key Researchers in North American Higher Education Teaching and Learning

    ERIC Educational Resources Information Center

    Kandlbinder, Peter

    2015-01-01

    Universities in the English-speaking world share a common ancestry that extends back to medieval times. From these beginnings universities quickly developed distinctive qualities as they became integrated within different social and cultural systems of their home societies. A number of comparisons of higher education research have shown major…

  15. Reflective Practice and Motion Sickness: Thoughts on the First North American Action Research Study Day

    ERIC Educational Resources Information Center

    Rowell, Lonnie; Inoue, Noriyuki; Getz, Cheryl

    2014-01-01

    This paper examines the experience of an action research "Study Day" to investigate development of a culture of reflective practice among educators. Shared recognition of the importance of reflective practice in education is now a well-established part of both pre-service preparation and in-service work experience for educators. Osterman…

  16. Fate of organic contaminants in a boreal forest catchment

    NASA Astrophysics Data System (ADS)

    Bergknut, Magnus; Meijer, Sandra; Halsall, Crispin; Ågren, Anneli; Laudon, Hjalmar; Köhler, Stephan; Jones, Kevin; Tysklind, Mats; Wiberg, Karin

    2010-05-01

    organic carbon and soil-water dissolved organic carbon (DOC) content. Significant differences in export of POPs were apparent between the forested and mire areas, and this could be linked to observed differences in hydrology, biogeochemistry and flux of DOC. Levels of POPs in surface water along the water path from the studied catchment to the Baltic Sea (the Gulf of Bothnia subbasin) were measured and the results showed that for this water system, atmospherically derived diffuse pollution has impact on the surface water quality in addition to downstream point sources. In conclusion, it is evident that a full understanding of the baseline contribution and the soil-to-water processes controlling the transport of priority substances at catchment scale is a prerequisite for assessing the variation of priority substances in water streams and river basins on a seasonal and regional scale. It is also clear that mobilization of headwater atmospherically derived diffuse pollution may have an impact on stream water quality in addition to downstream point sources. The above findings are applicable to a wide variety of north European catchments systems and provide an integrated and process-based understanding of base-line contamination of major catchments. The presented data highlight the findings from the PERSPEC project, which was possible under the umbrella of the European Commission's 6th Framework Programme project SNOWMAN (contract no ERAC-CT-2003-003219).

  17. Integrated monitoring of nitrogen dynamics in contrasting catchments

    NASA Astrophysics Data System (ADS)

    Schwientek, M.; Fleischer, M.

    2012-04-01

    The research institute WESS (Water & Earth System Science) is monitoring three adjacent meso-scale catchments (72 - 140 km2) in southwest Germany with respect to water quantity and quality. Due to their spatial proximity, the studied catchments are similar regarding climatic conditions and water balance. Geology is characterized by sedimentary rocks which are partly karstified. The catchments contrast strongly in land use and show a range from predominantly agriculture to almost exclusively forestry. In this context, a special focus of our research is the distinction of matter coming from the catchment area versus substances stemming from urban point sources. One important compound representing inputs from the catchment area is nitrogen. Nitrogen is an essential nutrient governing plant growth. If available in excess it leads to eutrophication and is therefore one of the globally most widespread contaminants in aquatic ecosystems. Transport of human-derived nitrogen through landscapes including urban areas to the oceans predominantly occurs via river network systems. Hence, monitoring of nitrogen fluxes in streams and rivers reveals mechanisms and dynamics of its transport and gives also insight into hydrologic processes which influence the mobilization of nitrogen. Presently, the catchments are equipped with online probes enabling high resolution monitoring of nitrate concentrations and other parameters. We found that average nitrate concentrations in stream water perfectly reflect the portion of fertilized arable land. The dynamics of N transport, however, largely depends on the hydrologic system and is driven by the dominating runoff generation processes. The interplay between different hydrological storages, which eventually also act as N pools, turns out to be decisive for the temporal variability of N concentrations in stream discharge. Inversely, the study of N transport dynamics can be used to infer the hydrologic mechanisms responsible for N mobilization

  18. Interactive Effects of Storms, Drought, and Weekly Land Cover Changes on Water Quality Patterns in an Agricultural-dominated Subtropical Catchment in New Zealand

    NASA Astrophysics Data System (ADS)

    Julian, J.; Owsley, B.; de Beurs, K.; Hughes, A.

    2013-12-01

    Rivers are the funnels of landscapes, with the quality of water at the catchment outlet reflecting interactions among geomorphic processes, vegetation characteristics, weather patterns, and anthropogenic land uses. The impacts of changing climate and land cover on water quality are not straightforward; but instead, are set by the interaction of numerous landscape components at multiple spatiotemporal scales. In agricultural-dominated subtropical landscapes such as the Hoteo River Catchment in northern North Island of New Zealand, the land surface can be very dynamic, responding quickly to storms, drought, forest clearings, and grazing practices. In order to capture these short-term fluctuations, we created an 8-day land disturbance index for the catchment using MODIS Nadir BRDF-adjusted reflectance (NBAR) data (500 meter resolution) from 2000 to 2013. We also fused this time-series with Landsat TM/ETM surface reflectance data (30 meter resolution) to more precisely capture the location and extent of these land disturbances. This high-resolution land disturbance time-series was then compared to daily rainfall, daily river discharge, and monthly water samples to assess the effects of changing weather and land cover on a suite of water quality variables including water clarity, turbidity, ammonium (NH4), nitrate (NO3), total nitrogen (TN), dissolved reactive phosphate (DRP), total phosphorus (TP), and fecal coliforms. Forest clearings in the early part of our study period created the most intense land disturbances, which led to elevated turbidity and DRP during subsequent storms. Pasture areas during drought were also characterized by high disturbance indices, particularly in 2013 - the worst drought on record for northern New Zealand. Seasonal effects on land disturbance and water quality were also detected, especially for water clarity and turbidity. From 2011 to 2013, river discharge and turbidity from three sub-catchments were measured at 5-minute intervals to

  19. Monitoring of initial patterns and structures in an artificial catchment

    NASA Astrophysics Data System (ADS)

    Schaaf, Wolfgang; Gerwin, Werner; Biemelt, Detlef; Fischer, Anton

    2010-05-01

    To combine process-oriented research on initial development of ecosystems with interactions and co-development of spatial patterns and structures the Transregional Collaborative Research Centre (SFB/TRR) 38 (www.tu-cottbus.de/sfb_trr) was established as an initiative of three universities (BTU Cottbus, TU Munich and ETH Zurich). The objective of the SFB/TRR 38 is to enhance our understanding of structure genesis in ecosystems and of process dynamics as well as their interactions during the initial development phase. The aim is to integrate these feedback mechanisms in the analysis of water and element budgets at the catchment scale and to implement them into models. To allow the clear definition of starting conditions at ´point zeró and to be able to integrate spatially distributed processes and patterns to larger units, an artificial catchment was constructed in the mining area of Lusatia/Germany as the main research site (Gerwin et al. 2009a). With an area of about 6 ha, this catchment ´Chicken Creeḱ is to our knowledge the largest artificial catchment worldwide. It was constructed as a 2-4 m layer of post-glacial sandy to loamy sediments overlying a 1-2 m layer of Tertiary clay that forms a shallow pan and seals the whole catchment at the base. No further measures of restoration like planting, amelioration or fertilization were carried out to allow natural succession and undisturbed development. Due to the artificial construction, boundary conditions of this site are clearly defined including well documented inner structures as compared to natural catchments. It is assumed that the interaction of patterns and processes during initial development will proceed from simpler to more complex states of the systems and that different stages along this phase can be identified at the catchment level. Changes within the catchment are intensively monitored since 2005, when construction finished (Gerwin et al. 2009b), including intensive on-site measurements and micro

  20. Digital catchment observatories: A platform for engagement and knowledge exchange between catchment scientists, policy makers, and local communities

    NASA Astrophysics Data System (ADS)

    Mackay, E. B.; Wilkinson, M. E.; Macleod, C. J. A.; Beven, K.; Percy, B. J.; Macklin, M. G.; Quinn, P. F.; Stutter, M.; Haygarth, P. M.

    2015-06-01

    Increasing pressures on the hydrological cycle from our changing planet have led to calls for a refocus of research in the sciences of hydrology and water resources. Opportunities for new and innovative research into these areas are being facilitated by advances in the use of cyberinfrastructure, such as the development of digital catchment observatories. This is enabling research into hydrological issues such as flooding to be approached differently. The ability to combine different sources of data, knowledge, and modeling capabilities from different groups such as scientists, policy makers, and the general public has the potential to provide novel insights into the way individual catchments respond at different temporal and spatial scales. While the potential benefits of the digital catchment observatory are large, this new way of carrying out research into hydrological sciences is likely to prove challenging on many levels. Along with the obvious technical and infrastructural challenges to this work, an important area for consideration is how to enable a digital observatory to work for a range of potential end-users, paving the way for new areas of research through developing a platform effective for engagement and knowledge exchange. Using examples from the recent local-scale hydrological exemplar in the Environmental Virtual Observatory pilot project (http://www.evo-uk.org), this commentary considers a number of issues around the communication between and engagement of different users, the use of local knowledge and uncertainty with cloud-based models, and the potential for decision support and directions for future research.

  1. 2011 Photosynthesis Gordon Research Conference & Seminar (June 11-17, 2011, Davidson College, Davidson, North Carolina)

    SciTech Connect

    Prof. Krishna Niyogi

    2011-06-17

    Photosynthesis is the biological process that converts solar energy into chemical energy. Elucidation of the mechanisms of photosynthetic energy conversion at a molecular level is fundamentally important for understanding the biology of photosynthetic organisms, for optimizing biological solar fuels production, and for developing biologically inspired approaches to solar energy conversion. The 2011 Gordon Conference on Photosynthesis will present cutting-edge research focusing on the biochemical aspects of photosynthesis, including: (1) structure, assembly, and function of photosynthetic complexes; (2) the mechanism of water splitting by PSII; (3) light harvesting and quenching; (4) alternative electron transport pathways; (5) biosynthesis of pigments and cofactors; and (6) improvement of photosynthesis for bioenergy and food production. Reflecting the interdisciplinary nature of photosynthesis research, a diverse group of invited speakers will represent a variety of scientific approaches to investigate photosynthesis, such as biochemistry, molecular genetics, structural biology, systems biology, and spectroscopy. Highly interactive poster sessions provide opportunities for graduate students and postdocs to present their work and exchange ideas with leaders in the field. One of the highlights of the Conference is a session featuring short talks by junior investigators selected from the poster presentations. The collegial atmosphere of the Photosynthesis GRC, with programmed discussion sessions as well as informal gatherings in the afternoons and evenings, enables participants to brainstorm, exchange ideas, and forge new collaborations. For the second time, this Conference will be immediately preceded by a Gordon Research Seminar on Photosynthesis (June 11-12, 2011, at the same location), with a focus on 'Photosynthesis, Bioenergy, and the Environment.' The GRS provides an additional opportunity for graduate students and postdocs to present their research, and it

  2. Identifying hydrological responses of micro-catchments under contrasting land use in the Brazilian Cerrado

    NASA Astrophysics Data System (ADS)

    Nobrega, R. L. B.; Guzha, A. C.; Torres, G. N.; Kovacs, K.; Lamparter, G.; Amorim, R. S. S.; Couto, E.; Gerold, G.

    2015-09-01

    topographic characteristics, and low-till farming techniques in the cropland catchment, additionally to the buffering effect of the gallery forests in these catchments. Although the results of this study provide a useful assessment of catchment rainfall-runoff controls in the Brazilian Cerrado landscape, further research is required to include quantification of the influence of the gallery forests on both hydrological and hydrochemical fluxes, which are important for watershed management and ecosystem services provisioning.

  3. SWAT-CS: Revision and testing of SWAT for Canadian Shield catchments

    NASA Astrophysics Data System (ADS)

    Fu, Congsheng; James, April L.; Yao, Huaxia

    2014-04-01

    Canadian Shield catchments are under increasing pressure from various types of development (e.g., mining and increased cottagers) and changing climate. Within the southern part of the Canadian Shield, catchments are generally characterized by shallow forested soils with high infiltration rates and low bedrock infiltration, generating little overland flow, and macropore and subsurface flow are important streamflow generation processes. Large numbers of wetlands and lakes are also key physiographic features, and snow-processes are critical to catchment modeling in this climate. We have revised the existing, publicly available SWAT (version 2009.10.1 Beta 3) to create SWAT-CS, a version representing hydrological processes dominating Canadian Shield catchments, where forest extends over Precambrian Shield bedrock. Prior to this study, very few studies applying SWAT to Canadian Shield catchments exist (we have found three). We tested SWAT-CS using the Harp Lake catchment dataset, an Ontario Ministry of Environment research station located in south-central Ontario. Simulations were evaluated against 30 years of observational data, including streamflow from six headwater sub-catchments (0.1-1.9 km2), outflow from Harp Lake (5.4 km2) and five years of weekly snow water equivalent (SWE). The best Nash-Sutcliffe efficiency (NSE) results for daily streamflow calibration, daily streamflow validation, and SWE were 0.60, 0.65, and 0.87, respectively, for sub-catchment HP4 (with detailed land use and soil data). For this range of catchment scales, land cover and soil properties were found to be transferable across sub-catchments with similar physiographic features, namely streamflow from the remaining five sub-catchments could be modeled well using sub-catchment HP4 parameterization. The Harp Lake outflow was well modeled using the existing reservoir-based target release method, generating NSEs of 0.72 and 0.67 for calibration and verification periods respectively. With

  4. Dispersion mechanisms and the effect of parameter uncertainty on hydrologic response in urban catchments

    NASA Astrophysics Data System (ADS)

    Cantone, Joshua; Schmidt, Arthur

    2011-05-01

    The link between river network structure and hydrologic response for natural watersheds has been the subject of ongoing research for the past 30 years. In this paper we investigate the link between sewer network structure and hydrologic response in urban catchments. It has been shown in natural watersheds that there are dispersion mechanisms that contribute to the impulse response function of the catchment: hydrodynamic dispersion, geomorphologic dispersion, and hydrodynamic dispersion. We introduce a fourth dispersion mechanism, intrastate dispersion, which accounts for the variance in conduit (e.g., slope, length, diameter, etc.) and overland region input parameters (e.g., slope, area, imperviousness, etc.) within an order. This dispersion mechanism is found to be the second largest contributor to the total dispersion in the urban catchments analyzed, contributing less than hydrodynamic dispersion but more than kinematic and geomorphologic dispersion. This is primarily a result of the shorter network travel times observed in urban catchment. The dispersion mechanisms are incorporated in the Illinois Urban Hydrologic Model, which is a recently developed probabilistic approach for predicting the hydrologic response in highly urbanized catchments. Furthermore, an analysis is performed to help better understand the uncertainty in the predicted hydrologic response that is introduced by spatial variation in conduit and overland input parameters. It is identified that conduit slope and length are the greatest sources of uncertainty in the predicted direct runoff hydrograph for the CDS-51 catchment in the village of Dolton, Illinois, and the CDS-36 catchment in the city of Chicago, Illinois.

  5. Ecology and biology of paddlefish in North America: historical perspectives, management approaches, and research priorities

    USGS Publications Warehouse

    Jennings, Cecil A.; Zigler, Stephen J.

    2000-01-01

    Paddlefish (Polyodon spathula, Polyodontidae) are large, mostly-riverine fish that once were abundant in medium- to large-sized river systems throughout much of the central United States. Concern for paddlefish populations has grown from a regional fisheries issue to one of national importance for the United States. In 1989, the U.S. Fish and Wildlife Service (USFWS) was petitioned to list paddlefish as a federally threatened species under the Endangered Species Act. The petition was not granted, primarily because of a lack of empirical data on paddlefish population size, age structure, growth, or harvest rates across the present 22-state range. Nonetheless, concern for paddlefish populations prompted the USFWS to recommend that paddlefish be protected through the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). The addition of paddlefish to Appendix II of CITES, which was approved in March 1992, provides a mechanism to curtail illegal trade in paddlefish and their parts and supports a variety of conservation plans. Paddlefish populations have been negatively affected by overharvest, river modifications, and pollution, but the paddlefish still occupies much of its historic range and most extant populations seem to be stable. Although many facets of paddlefish biology and ecology are well understood, the lack of information on larval and juvenile ecology, mechanisms that determine recruitment, population size and vital rates, interjurisdictional movements, and the effects of anthropogenic activities present significant obstacles for managing paddlefish populations. Questions about the size and structure of local populations, and how such populations are affected by navigation traffic, dams, and pollution are regarded as medium priority areas for future research. The availability of suitable spawning habitat and overall reproductive success in impounded rivers are unknown and represent critical areas for future research

  6. Space and Atmospheric Physics Education and Research at North Carolina A&T State University

    NASA Astrophysics Data System (ADS)

    Nair, J. R.; Smith, G.; Kebede, A.

    2006-11-01

    gutaye@ncat.edu In this communication we discuss the new undergraduate and graduate space and atmospheric physics program at NC A&T State University. The program is designed to train future generation space scientists to meet the workforce needs of NASA, aerospace industries and academic institutions. In order to fortify this effort, we have initiated collaboration with US Air Force, GSFC and University of Michigan. We plan to contribute to the current scientific issues associated with TEC variations, scintillations and disturbances, and the morphology/manifestations of Ionospheric Spread F phenomena, and their variations with locations, specifically over low and mid-latitudes. In order to facilitate research we plan to install a magnetometer, a coherent beacon receiver and GPS receivers. In the long run the space science research community and K12 students and teachers will use of these facilities. We will discuss our recent experience during the IHY-SCINDA 2006 workshop, in Sal Cape Verde, as well as the plans of the upcoming IHY-Africa workshop, November 5-9, 2007 Addis Ababa Ethiopia.

  7. Catchment classification by means of hydrological models

    NASA Astrophysics Data System (ADS)

    Hellebrand, Hugo; Ley, Rita; Casper, Markus

    2013-04-01

    An important hydrological objective is catchment classification that will serve as a basis for the regionalisation of discharge parameters or model parameters. The main task of this study is the development and assessment of two classification approaches with respect to their efficiency in catchment classification. The study area in western Germany comprises about 80 catchments that range in size from 8 km2 up to 1500 km2, covering a wide range of geological substrata, soils, landscapes and mean annual precipitation. In a first approach Self Organising Maps (SOMs) use discharge characteristics or catchment characteristics to classify the catchments of the study area. Next, a reference hydrological model calibrates the catchments of the study area and tests the possibilities of parameter transfer. Compared to the transfer of parameters outside a class, for most catchments the model performance improves when parameters within a class are transferred. Thus, it should be possible to distinguish catchment classes by means of a hydrological model. The classification results of the SOM are compared to the classification results of the reference hydrological model in order to determine the latter validity. The second approach builds on the first approach in such a way that it uses the Superflex Modelling Framework instead of only one reference model. Within this framework multiple conceptual model structures can be calibrated and adapted. Input data for each calibration of a catchment are hourly time series of runoff, precipitation and evaporation for at least eight years. The calibration of multiple models for each catchment and their comparison allows for the assessment of the influence of different model structures on model performance. Learning loops analyse model performance and adapt model structures accordingly with a view to performance improvement. The result of the modelling exercise is a best performing model structure for each catchment that serves as a basis

  8. Hydrological response of the Mediterranean catchments- A review

    NASA Astrophysics Data System (ADS)

    Merheb, Mohammad; Moussa, Roger; Abdallah, Chadi; Colin, François; Perrin, Charles; Baghdadi, Nicolas

    2015-04-01

    The Mediterranean region is a water stressed environment with increasing climatic and anthropogenic pressures. This work presents a review of 120 hydrological studies carried out in the Mediterranean region. It contributes to the ongoing hydrological research initiative on "Hydrology in a changing world" launched by the IAHS in 2014. It aims to understand the characteristics of hydrological response under Mediterranean conditions, taking into account changes driven by anthropogenic and climatic factors; and to compare modeling and regionalization approaches in use. The study region is divided into three sub-regions: Northwestern Mediterranean (NWM), Eastern (EM) and Southern Mediterranean (SM). Information on catchments responses and modeling approaches at different time scales (annual, dry season and event) were extracted from published studies, and analyzed. Results indicate regional discrepancies (between NWM, EM and SM sub-regions) in the distribution of climatic and hydrological response characteristics at the annual and the event scale. The NWM catchments are the wettest, and the SM catchments are the driest, while the EM catchments are intermediate and exhibit the largest variability. The NWM sub-region shows the most extreme rainfall regime in the Mediterranean, particularly, in an arc that extends from Northeastern Spain to Northeastern Italy. Observations indicate decreasing tendency in water resources due to both anthropogenic and climatic impacts, and a more extreme rainfall regime. Moreover, Mediterranean catchments show very heterogeneous responses in time and space which make the modeling of their hydrological functioning very complicated and data demanding, with increasing model limitations and uncertainties. Nevertheless, the models in use are classical ones; very few were developed to address these regional specificities. Regionalization studies in the Mediterranean are scarce even in term of low flows and FDCs which is surprising in a water

  9. Doing Institutional Research: A Focus on Professional Development. Papers from the Annual Meeting of the North East Association for Institutional Research (9th, Durham, New Hampshire, October 17-19, 1982).

    ERIC Educational Resources Information Center

    Green, Diana M., Ed.

    Institutional research that focuses on professional development is addressed in 35 papers from the 1982 meeting of the North East Association for Institutional Research. Titles and authors include the following: "Modeling College Student Adjustment and Retention for the Individual Institution" (Norman D. Aitken); "The Development Saga of an…

  10. Sailing into the New Millennium: Charting the Course for Institutional Research. North East Association for Institutional Research Annual Conference Proceedings (26th, Newport, Rhode Island, November 13-16, 1999).

    ERIC Educational Resources Information Center

    North East Association for Institutional Research.

    This proceedings contains papers from the 1999 annual conference of the North East Association for Institutional Research. The papers are: (1) "A Marketing Research Program for Commuter Colleges" (Michelle S. Appel and Craig A. Clagett); (2) "Where Do I Start? Determining Institutional Information Needs beyond Mandated Reporting" (Michelle S.…

  11. Investigation of comparative effectiveness research in Asia, Europe, and North America

    PubMed Central

    Patel, Isha; Rarus, Rachel; Tan, Xi; Lee, EK; Guy, Jason; Ahmad, Akram; Chang, Jongwha

    2015-01-01

    Comparative effectiveness research (CER) is an important branch of pharmacoeconomics that systematically studies and evaluates the cost-effectiveness of medical interventions. CER plays instrumental roles in guiding government public health policy programs and insurance. Countries throughout the world use different methods of CER to help make medical decisions based on providing optimal therapy at a reduced cost. Expenses to the healthcare system continue to rise, and CER is one-way in which expenses could be curbed in the future by applying cost-effectiveness evidence to clinical decisions. China, India, South Korea, and the United Kingdom are of essential focus because these country's economies and health care expenses continue to expand. The structures and use of CER are diverse throughout these countries, and each is of prime importance. By conducting this thorough comparison of CER in different nations, strategies and organizational setups from different countries can be applied to help guide public health and medical decision-making in order to continue to expand the establishment and role of CER programs. The patient-centered medical home has been created to help reduce costs in the primary care sector and to help improve the effectiveness of therapy. Barriers to CER are also important as many stakeholders need to be able to work together to provide the best CER evidence. The advancement of CER in multiple countries throughout the world provides a possible way of reducing costs to the healthcare system in an age of expanding expenses. PMID:26729947

  12. Investigation of comparative effectiveness research in Asia, Europe, and North America.

    PubMed

    Patel, Isha; Rarus, Rachel; Tan, Xi; Lee, E K; Guy, Jason; Ahmad, Akram; Chang, Jongwha

    2015-01-01

    Comparative effectiveness research (CER) is an important branch of pharmacoeconomics that systematically studies and evaluates the cost-effectiveness of medical interventions. CER plays instrumental roles in guiding government public health policy programs and insurance. Countries throughout the world use different methods of CER to help make medical decisions based on providing optimal therapy at a reduced cost. Expenses to the healthcare system continue to rise, and CER is one-way in which expenses could be curbed in the future by applying cost-effectiveness evidence to clinical decisions. China, India, South Korea, and the United Kingdom are of essential focus because these country's economies and health care expenses continue to expand. The structures and use of CER are diverse throughout these countries, and each is of prime importance. By conducting this thorough comparison of CER in different nations, strategies and organizational setups from different countries can be applied to help guide public health and medical decision-making in order to continue to expand the establishment and role of CER programs. The patient-centered medical home has been created to help reduce costs in the primary care sector and to help improve the effectiveness of therapy. Barriers to CER are also important as many stakeholders need to be able to work together to provide the best CER evidence. The advancement of CER in multiple countries throughout the world provides a possible way of reducing costs to the healthcare system in an age of expanding expenses. PMID:26729947

  13. Special issue on mercury in Canada's North: summary and recommendations for future research.

    PubMed

    Chételat, John; Braune, Birgit; Stow, Jason; Tomlinson, Scott

    2015-03-15

    Important scientific advances have been made over the last decade in identifying the environmental fate of mercury and the processes that control its cycling in the Canadian Arctic. This special issue includes a series of six detailed reviews that summarize the main findings of a scientific assessment undertaken by the Government of Canada's Northern Contaminants Program. It was the first assessment to focus exclusively on mercury pollution in the Canadian Arctic. Key findings, as detailed in the reviews, relate to sources and long-range transport of mercury to the Canadian Arctic, its cycling within marine, freshwater, and terrestrial environments, and its bioaccumulation in, and effects on, the biota that live there. While these accomplishments are significant, the complex nature of the mercury cycle continues to provide challenges in characterizing and quantifying the relationships of mercury sources and transport processes with mercury levels in biota and biological effects of mercury exposure. Of particular concern are large uncertainties in our understanding of the processes that are contributing to increasing mercury concentrations in some Arctic fish and wildlife. Specific recommendations are provided for future research and monitoring of the environmental impacts of anthropogenic mercury emissions, influences of climate change, and the effectiveness of mitigation strategies for mercury in the Canadian Arctic. PMID:25669603

  14. Further research at the Oldowan site of Ain Hanech, North-eastern Algeria.

    PubMed

    Sahnouni, Mohamed; Hadjouis, Djillali; van der Made, Jan; Derradji, Abd El-Kader; Canals, Antoni; Medig, Mohamed; Belahrech, Hocine; Harichane, Zoheir; Rabhi, Merouane

    2002-12-01

    Further investigations were carried out at Ain Hanech, Algeria in 1998 and 1999 to explore its potential for investigating early hominid behavioral patterns and adaptation. Research concentrated on the stratigraphy and dating, identifying new archaeological deposits, and excavating the Ain Hanech and El-Kherba localities. To enhance the chronological control within a biostratigraphic framework, the Ain Boucherit fossil-bearing stratum, yielding a Plio-Pleistocene fauna, is correlated with the regional stratigraphy. In the stratigraphic sequence, the Ain Boucherit stratum, located 13m below the Ain Hanech Oldowan occurrences, is found in Unit Q of the Ain Hanech Formation. Unit Q shows a paleomagnetically reversed polarity, which may be correlated with an age earlier than the Olduvai normal subchron (1.95-1.77Ma). Based on test trenches and stratigraphic analyses, additional Oldowan deposits A, B, and C are identified at Ain Hanech. All three deposits and the El-Kherba site contain Mode I technology artefacts associated with an Early Pleistocene fauna. El-Kherba is stratigraphically equivalent to Ain Hanech. These two archaeological sites are estimated to be dated to about 1.8Ma. PMID:12473489

  15. Hydropedological insights when considering catchment classification

    NASA Astrophysics Data System (ADS)

    Bouma, J.; Droogers, P.; Sonneveld, M. P. W.; Ritsema, C. J.; Hunink, J. E.; Immerzeel, W. W.; Kauffman, S.

    2011-06-01

    Soil classification systems are analysed to explore the potential of developing classification systems for catchments. Soil classifications are useful to create systematic order in the overwhelming quantity of different soils in the world and to extrapolate data available for a given soil type to soils elsewhere with identical classifications. This principle also applies to catchments. However, to be useful, soil classifications have to be based on permanent characteristics as formed by the soil forming factors over often very long periods of time. When defining permanent catchment characteristics, discharge data would therefore appear to be less suitable. But permanent soil characteristics do not necessarily match with characteristics and parameters needed for functional soil characterization focusing, for example, on catchment hydrology. Hydropedology has made contributions towards the required functional characterization of soils as is illustrated for three recent hydrological catchment studies. However, much still needs to be learned about the physical behaviour of anisotropic, heterogeneous soils with varying soil structures during the year and about spatial and temporal variability. The suggestion is made therefore to first focus on improving simulation of catchment hydrology, possibly incorporating hydropedological expertise, before embarking on a catchment classification effort which involves major input of time and involves the risk of distraction. In doing so, we suggest to also define other characteristics for catchment performance than the traditionally measured discharge rates. Such characteristics may well be derived from societal issues being studied, as is illustrated for the Green Water Credits program.

  16. Institutional Research in Emerging Countries of Southern Africa, Latin America, and the Middle East and North Africa: Global Frameworks and Local Practices

    ERIC Educational Resources Information Center

    Lange, Lis; Saavedra, F. Mauricio; Romano, Jeanine

    2013-01-01

    This chapter presents a synthesis of the conceptualization and practice of institutional research (IR) in higher education (HE) in emerging countries across Southern Africa, Latin America and the Middle East and North Africa (MENA) regions. The chapter contextualizes the growing need for IR in these regions, identifies problems and challenges…

  17. Assessment: Fad or Fact of Life? Proceedings of the North East Association for Institutional Research Annual Conference (14th, Rochester, New York, October 25-27, 1987).

    ERIC Educational Resources Information Center

    North East Association for Institutional Research.

    Assessment in higher education is addressed in these proceedings of the 1987 conference of the North East Association for Institutional Research. Papers and authors include: "Assessing the Status of Assessment" (Peter T. Ewell); "Has the Middle Class Been Pressured the Most? Multivariate Analysis of Parental Contributions to Higher Education"…

  18. Planning for Quality. Papers presented at the Annual Meeting of the North East Association for Institutional Research (8th, Princeton, New Jersey, November 5-7, 1981).

    ERIC Educational Resources Information Center

    North East Association for Institutional Research.

    The proceedings of the annual conference of the North East Association for Institutional Research, whose theme was "Planning for Quality," are presented. The 26 papers were divided into the following topics: admissions, assessment, enrollment, faculty and staff, outcomes, planning, programs and retention, the environment, and the field of…

  19. METHODOLOGIES AND PROTOCOLS IN CLINICAL RESEARCH: EVALUATING ENVIRONMENTAL EFFECTS IN MAN - PROCEEDINGS OF A SYMPOSIUM HELD AT CHAPEL HILL, NORTH CAROLINA OCTOBER 26-28, 1977

    EPA Science Inventory

    The report is a proceedings of a symposium convened at Chapel Hill, North Carolina, October 26-28, 1977. Five major topics pertaining to the use of humans as experimental subjects are addressed in this volume: philosophy of clinical research, environmental and physical safety con...

  20. The North Carolina Youth Empowerment Study (NCYES): A Participatory Research Study Examining the Impact of Youth Empowerment for Tobacco Use Prevention

    ERIC Educational Resources Information Center

    Ribisl, Kurt M.; Steckler, Allan; Linnan, Laura; Patterson, Carol C.; Pevzner, Eric S.; Markatos, Elizabeth; Goldstein, Adam O.; McGloin, Tim; Peterson, Arlana Bobo

    2004-01-01

    This article describes the North Carolina Youth Empowerment Study (NCYES), a 3-year participatory evaluation of youth programs addressing tobacco use prevention. The study goals of NCYES were to (1) convene an advisory board comprised of lay youths and adults in a participatory research process, (2) document the characteristics of youth programs…

  1. Numerical Research of Steam and Gas Plant Efficiency of Triple Cycle for Extreme North Regions

    NASA Astrophysics Data System (ADS)

    Galashov, Nikolay; Tsibulskii, Svjatoslav; Matveev, Aleksandr; Masjuk, Vladimir

    2016-02-01

    The present work shows that temperature decrease of heat rejection in a cycle is necessary for energy efficiency of steam turbine plants. Minimum temperature of heat rejection at steam turbine plant work on water steam is 15°C. Steam turbine plant of triple cycle where lower cycle of steam turbine plant is organic Rankine cycle on low-boiling substance with heat rejection in air condenser, which safely allows rejecting heat at condensation temperatures below 0°C, has been offered. Mathematical model of steam and gas plant of triple cycle, which allows conducting complex researches with change of working body appearance and parameters defining thermodynamic efficiency of cycles, has been developed. On the basis of the model a program of parameters and index cycles design of steam and gas plants has been developed in a package of electron tables Excel. Numerical studies of models showed that energy efficiency of steam turbine plants of triple cycle strongly depend on low-boiling substance type in a lower cycle. Energy efficiency of steam and gas plants net 60% higher can be received for steam and gas plants on the basis of gas turbine plant NK-36ST on pentane and its condensation temperature below 0°C. It was stated that energy efficiency of steam and gas plants net linearly depends on condensation temperature of low-boiling substance type and temperature of gases leaving reco very boiler. Energy efficiency increases by 1% at 10% decrease of condensation temperature of pentane, and it increases by 0.88% at 15°C temperature decrease of gases leaving recovery boiler.

  2. Building Partnerships and Research Collaborations to Address the Impacts of Arctic Change: The North Atlantic Climate Change Collaboration (NAC3)

    NASA Astrophysics Data System (ADS)

    Polk, J.; North, L. A.; Strenecky, B.

    2015-12-01

    Changes in Arctic warming influence the various atmospheric and oceanic patterns that drive Caribbean and mid-latitude climate events, including extreme events like drought, tornadoes, and flooding in Kentucky and the surrounding region. Recently, the establishment of the North Atlantic Climate Change Collaboration (NAC3) project at Western Kentucky University (WKU) in partnership with the University of Akureyri (UNAK), Iceland Arctic Cooperation Network (IACN), and Caribbean Community Climate Change Centre (CCCCC) provides a foundation from which to engage students in applied research from the local to global levels and more clearly understand the many tenets of climate change impacts in the Arctic within both a global and local community context. The NAC3 project encompasses many facets, including joint international courses, student internships, economic development, service learning, and applied research. In its first phase, the project has generated myriad outcomes and opportunities for bridging STEM disciplines with other fields to holistically and collaboratively address specific human-environmental issues falling under the broad umbrella of climate change. WKU and UNAK students desire interaction and exposure to other cultures and regions that are threatened by climate change and Iceland presents a unique opportunity to study influences such as oceanic processes, island economies, sustainable harvest of fisheries, and Arctic influences on climate change. The project aims to develop a model to bring partners together to conduct applied research on the complex subject of global environmental change, particularly in the Arctic, while simultaneously focusing on changing how we learn, develop community, and engage internationally to understand the impacts and find solutions.

  3. Process type identification in torrential catchments

    NASA Astrophysics Data System (ADS)

    Heiser, Micha; Scheidl, Christian; Eisl, Julia; Spangl, Bernhard; Hübl, Johannes

    2015-04-01

    The classification of torrential processes takes place according to factors like sediment concentration and flow behavior and ranges from fluvial process types, including water floods and fluvial sediment transport processes, to fluvial mass movements such as debris flows. This study hypothises a context between basic geomorphological disposition parameters and potential dominant flow process types in steep headwater catchments. Thus, examined catchments were selected based on a historical event documentation of torrential events in the Austrian Alps. In total, 84 catchments could be analysed, and 11 different morphometric parameters were considered. To predict the dominant torrential process type within a catchment, a naive Bayes classifier, a decision tree model, and a multinomial regression model was trained against the compiled geomorphological disposition parameters. All models as well as their combination were compared, based on bootstrapping and complexity. The presented classification model with the lowest prediction error for our data might help to identify the most likely torrential process within a considered catchment.

  4. The missing flux in a 35S budget for the soils of a small polluted catchment

    USGS Publications Warehouse

    Novak, M.; Michel, R.L.; Prechova, E.; Stepanova, M.

    2004-01-01

    A combination of cosmogenic and artificial 35S was used to assess the movement of sulfur in a steep Central European catchment affected by spruce die-back. The Jezer??i?? catchment, Krus??ne?? Hory Mts. (Czech Republic) is characterized by a large disproportion between atmospheric S input and S output via stream discharge, with S output currently exceeding S input three times. A relatively high natural concentration of cosmogenic 35S (42 mBq L-1) was found in atmospheric deposition into the catchment in winter and spring of 2000. In contrast, stream discharge contained only 2 mBq L-1. Consequently, more than 95% of the deposited S is cycled or retained within the catchment for more than several months, while older S is exported via surface water. In spring, when the soil temperature is above 0 ??C, practically no S from instantaneous rainfall is exported, despite the steepness of the slopes and the relatively short mean residence time of water in the catchment (6.5 months). Sulfur cycling in the soil includes not just adsorption of inorganic sulfate and biological uptake, but also volatilization of S compounds back into the atmosphere. Laboratory incubations of an Orthic Podzol from Jezer??i?? spiked with h 720 kBq of artificial 35S showed a 20% loss of the spike within 18 weeks under summer conditions. Under winter conditions, the 35S loss was insignificant (< 5%). This missing S flux was interpreted as volatilized hydrogen sulfide resulting from intermittent dissimilatory bacterial sulfate reduction. The missing S flux is comparable to the estimated uncertainty in many catchment S mass balances (??10%), or even larger, and should be considered in constructing these mass balances. In severely polluted forest catchments, such as Jezer??i??, sulfur loss to volatilization may exceed 13 kg ha-1 a-1, which is more than the current total atmospheric S input in large parts of North America and Europe. ?? 2004 Kluwer Academic Publishers.

  5. Spatial variation in concentrations of dissolved nitrogen species in an upland blanket peat catchment.

    PubMed

    Cundill, A P; Chapman, P J; Adamson, J K

    2007-02-01

    The concentration of nitrogen (N), particularly as nitrate (NO3-N), in upland streams, lakes and rivers is frequently used as a diagnostic of the vulnerability of upland ecosystems to increased atmospheric nitrogen deposition and N saturation. The N content of running waters, however, is generally assessed on the basis of sampling at a limited number of points in space and time within the catchment under investigation. The current study was conducted at Trout Beck, an 11.5 km2 blanket peat-dominated catchment in the North Pennine uplands of the UK. Results from sampling at 33 sites within this catchment demonstrated that the concentrations of all dissolved N species were highly variable, even over short distances. Statistical relationships between the concentrations of NO3-N and dissolved organic nitrogen (DON) and percentage catchment cover of Calluna/Eriophorum and Eriophorum vegetation were found. However, it was also noted that in catchments containing limestone outcrops, NO3-N concentration was much higher than in catchments where runoff was sourced directly from the blanket peat surface. It is possible that NH4-N and DON leached from the blanket peat are mineralised and nitrified, providing a source for the NO3-N found in the river channels. Overall, the current study suggests that interpretations of N-saturation based on river water chemistry measurements at a single point must be treated cautiously, and that the influence of catchment-scale physical factors, such as vegetation and geology cover on the concentration of dissolved N species in upland river waters should not be ignored. PMID:17182088

  6. Modelling the impact of changing climate and forest cultivation on the water balance of a closed lake in North-east Germany

    NASA Astrophysics Data System (ADS)

    Natkhin, M.; Steidl, J.; Dietrich, O.

    2009-04-01

    Over the last 25 years declining water levels are observed in several lakes of forested catchments in North-east-Brandenburg (Germany). This region is located in the transition zone between maritime and continental climate. The annual lake evapotranspiration often exceeds the precipitation which annual average is below 600 mm year-1. So the groundwater recharge mainly controls the water supply of lakes. Changes of climate and forest cultivation can have highly influence on groundwater recharge. To identify and quantify the share of changes in climate and forest management in the decline of the lake water levels, the participating processes are separated and evaluated using water balance modelling in a small lowland catchment. The results and methods were used to predict the development of lake water levels in future. The lake Redernswalder See (0.5 km²) was chosen as subject of research. It has a forest dominated catchment (3.5 km²) and no outlet. Water gauge measurements over the last 25 years show a decline in lake water level by more than 3 m. Changes of climate and forest cultivation are actually observed and will alter the groundwater recharge in the catchment. Currently, the forest in the Redernswalder See catchment just as throughout North-East Brandenburg is dominated by pine monoculture. Depending on the climate conditions, groundwater recharge may be significantly lower under pine than under broad-leaved trees like beech or oak. Forestry plans to expand the share of beeches and oaks among mixed deciduous forest in future. The physically based distributed water balance model WaSiM-ETH is used to model groundwater recharge in the catchment and the lake water balance. The horizontal groundwater flow is handled by the built-in 2D groundwater model. This plays an important role as a connector between the lake and its catchment. To verify the hydrogeological conditions, a separate 3D groundwater model of this Late Pleistocene lowland catchment was built up

  7. A large scale girdling experiment in the TERENO Wüstebach catchment

    NASA Astrophysics Data System (ADS)

    Weihermüller, Lutz; Bogena, Heye; Herbst, Michael; Pütz, Thomas; Vereecken, Harry

    2010-05-01

    Forest ecosystems are in focus of various research projects analyzing soil-plant-atmosphere interactions. Understanding of the carbon budget and carbon fluxes in the different compartments (soil and plants) are of great importance to understand future climate change impact or the influence of management practice. For example, in forest stands soil respiration is the sum of heterotrophic and autotrophic respiration, whereby both fluxes can be only separated by root exclusion (trenching) or isotope techniques if the tree stand cannot not be disturbed. Another possibility to study soil respiration processes without altering the micro-meteorological conditions are girdling experiments. However, in practice girdling experiments are restricted to relatively small areas before clear-cutting. Additionally, most experiments were performed at plots, where the undisturbed processes are not well known. The proposed girdling experiment will take place in a mature spruce stand of approximately 60 years of age located in the Wüstebach catchment in North Rhine Westphalia, Germany. The 27 ha Wüstebach catchment is located in the Eifel low mountain range and is one out of four German Terrestrial Environmental Observatories (TERENO see also ttp://www.tereno.net/index.php?index=2). The catchment is permanently equipped with a wide range of sensors monitoring hydrological, meteorological, and biological processes. To monitor the soil water status a wireless sensor network of 150 sensor stations is already installed and monitors soil water content and soil temperature at 5, 20, and 50 cm depth. Hereby approximately 40 percent of all sensors are located within the area of projected clear cutting. Micrometeorological stations are equipped with standard weather data sensors. Additionally, a 30 m tower is equipped with an eddy covariance station. Soil respiration is measured using closed chamber technique since 2007 at predefined transects and nested points. A clear-cutting of about 40

  8. Modeling of matters removal from swampy catchment

    NASA Astrophysics Data System (ADS)

    Inishev, N. G.; Inisheva, L. I.

    2010-05-01

    the estimations were made taking into account layering unevenness of snow cover in deferent landscapes. Stored water distribution in the limits of every landscape was approximated by the curve of gamma distribution with parameters which are the results of snow survey. Everyday basin water yield was determined as difference between excesses of water coming above usage for filling of its water retaining tank. The size of the water retaining tank before start of snow melting depends on the basin wetting in the previous autumn. Autumn river flow is taken as a degree of water retaining tank filling before the snow melt. It is supposed that there is a process of water accumulation at slopes. Between theses water supplies and overland runoffs there is a nonlinear link. Temporary melt water detention, which comes from mire in swamp forest, is considered. Estimations are made individually for field, forest and swamp parts of the basin of the river Kljuch. Estimation of HA removal from the surface of catchment of the river Kljuch is taken as an example of model application. The results reveal possibilities of the given approach to modeling of dissolved matters removal from the swampy area. Acknowledgements: This research was supported by RFFR (No.No. 09-05-00235, 09-05-99007), Minister of education and science (No. 02.740.11.0325).

  9. Process scales in catchment science: a new synthesis

    NASA Astrophysics Data System (ADS)

    Price, K.; Dennedy-frank, P.; Harman, C. J.; Purucker, T.; Jackson, C. R.; Sidle, R. C.

    2013-12-01

    Concerns surrounding data resolution, choice of spatial and temporal scales in research design, and problems with extrapolation of processes across spatial and temporal scales differ greatly between scientific process-elucidation research and scenario exploration for watershed management and policy. This is true whether the underlying watershed models are statistical or process-based. Watershed scientists understand that we lack the knowledge and tools to extrapolate this detailed understanding from the smallest scales of observations to larger, more heterogeneous watershed systems over larger timescales, while it is at these larger scales where our most pressing questions of water availability lie, creating a conundrum that has stymied watershed science for several decades. As a scientific community, catchment scientists clearly understand the potential problems associated with up- and down-scaling in hydrology and related processes, but we suggest that the community lacks a cohesive perspective on how to deal with these issues. Having been nearly two decades since the last major review of this topic, we offer a new synthesis on the topic of scaling in catchment science with the results of four main objectives: 1) to identify a community definition of management and policy scales and their relationship to catchment process scales, 2) to synthesize legacy perspectives on scaling in hydrology, 3) to identify known scale-dependent and scale-invariant catchment processes , and 4) to suggest methods and conceptualizations for removal of scaling barriers in future research. Suggested approaches will incorporate trans-disciplinary perspectives on scaling, and will cover: thresholds for scale-dependence, the role of the representative elementary watershed in conceptualizing scaling, existing and potential use of scaling algorithms, strengths and weaknesses of cross-scale process-based modeling, and statistical approaches for maximizing observed information and

  10. Launch, Low-Speed, and Landing Characteristics Determined from the First Flight of the North American X-15 Research Airplane

    NASA Technical Reports Server (NTRS)

    Finch, Thomas W.; Matranga, Gene J.

    1959-01-01

    The first flight of the North American X-15 research airplane was made on June 8, 1959. This was accomplished after completion of a series of captive flights with the X-15 attached to the B-52 carrier airplane to demonstrate the aerodynamic and systems compatibility of the X-15//B-52 combination and the X-15 subsystem operation. This flight was planned as a glide flight so that the pilot need not be concerned with the propulsion system. Discussions of the launch, low-speed maneuvering, and landing characteristics are presented, and the results are compared with predictions from preflight studies. The launch characteristics were generally satisfactory, and the X-15 vertical tail adequately cleared the B-52 wing cutout. The actual landing pattern and landing characteristics compared favorably with predictions, and the recommended landing technique of lowering the flaps and landing gear at a low altitude appears to be a satisfactory method of landing the X-15 airplane. There was a quantitative correlation between flight-measured and predicted lift-drag-ratio characteristics in the clean configuration and a qualitative correlation in the landing configuration. A longitudinal-controllability problem, which became severe in the landing configuration, was evident throughout the flight and, apparently, was aggravated by the sensitivity of the side-located control stick. In the low-to-moderate angle-of-attack range covered, the longitudinal and directional stability were indicated to be adequate.

  11. The observed evapotranspiration combining the energy and water balance for different land use under semiarid Mediterranean catchment

    NASA Astrophysics Data System (ADS)

    Zitouna Chebbi, Rim; Mekki, Insaf; Jacob, Frédéric; Masmoudi, Moncef; Prévot, Laurent; Ben Mechlia, Netij; Voltz, Marc; Albergel, Jean

    2014-05-01

    The Mediterranean semiarid cultivated catchments are affected by global and climate change and are characterized by very complex hydrological systems. The improvement of their management requires a best understanding of the hydrological processes and developing reliable means for characterizing the temporal dynamics of soil water balance in a spatially distributed manner. The main objective of this study is: i) to analyze the observed evapotranspiration in relation to natural drivers (i.e. rainfall and soil properties) and anthropogenic forcing (i.e. land use and crop successions), and ) ii to assess the differences in both energy and water balances. We focus on a hilly semiarid Mediterranean catchment devoted to rainfed agriculture, so-called the Kamech catchment, which is located in the Cap Bon Peninsula, north-eastern Tunisia. The site belongs to the OMERE observatory for environmental research and it is monitored for the different hydrological cycle components under influence of anthropogenic forcing. The analysis is based on in-situ data measured under the common cereals/legumes/pasture cropping systems within the Kamech catchment. Energy and water balance components and vegetation parameters were collected in different fields and during various crop growth cycles. The results showed the highly variable response of energy and water balances depending on soil types, land use, and climatic conditions. The annual rainfall is mainly converted into evapotranspiration during the growing cycle for different land uses. The runoff amounts, for most of the sites, correspond to less than 10% of the rainfall amount. The evapotransipration ratios differed significantly across site and season in relation to soil properties and cumulated rainfall. We observe large differences in soil water dynamics among the legumes (fababean and chickpea) and cereals (wheat, oat, and triticale). Soil water is larger for legume crops, despite substantial plant growth during winter

  12. Regional health workforce planning through action research: lessons for commissioning health services from a case study in Far North Queensland.

    PubMed

    Panzera, Annette June; Murray, Richard; Stewart, Ruth; Mills, Jane; Beaton, Neil; Larkins, Sarah

    2016-01-01

    Creating a stable and sustainable health workforce in regional, rural and remote Australia has long been a challenge to health workforce planners, policy makers and researchers alike. Traditional health workforce planning is often reactive and assumes continuation of current patterns of healthcare utilisation. This demonstration project in Far North Queensland exemplifies how participatory regional health workforce planning processes can accurately model current and projected local workforce requirements. The recent establishment of Primary Health Networks (PHNs) with the intent to commission health services tailored to individual healthcare needs underlines the relevance of such an approach. This study used action research methodology informed by World Health Organization (WHO) systems thinking. Four cyclical stages of health workforce planning were followed: needs assessment; health service model redesign; skills-set assessment and workforce redesign; and development of a workforce and training plan. This study demonstrated that needs-based loco-regional health workforce planning can be achieved successfully through participatory processes with stakeholders. Stronger health systems and workforce training solutions were delivered by facilitating linkages and planning processes based on community need involving healthcare professionals across all disciplines and sectors. By focusing upon extending competencies and skills sets, local health professionals form a stable and sustainable local workforce. Concrete examples of initiatives generated from this process include developing a chronic disease inter-professional teaching clinic in a rural town and renal dialysis being delivered locally to an Aboriginal community. The growing trend of policy makers decentralising health funding, planning and accountability and rising health system costs increase the future utility of this approach. This type of planning can also assist the new PHNs to commission health services

  13. Climate-driven trends in the occurrence of major floods across North America and Europe

    NASA Astrophysics Data System (ADS)

    Hodgkins, Glenn A.; Whitfield, Paul H.; Burn, Donald H.; Hannaford, Jamie; Renard, Benjamin; Stahl, Kerstin; Fleig, Anne K.; Madsen, Henrik; Mediero, Luis; Korhonen, Johanna; Murphy, Conor; Crochet, Philippe; Wilson, Donna

    2016-04-01

    Every year river floods cause enormous damage around the world. Recent major floods in North America and Europe, for example, have received much press, with some concluding that these floods are more frequent in recent years as a result of anthropogenic warming. There has been considerable scientific effort invested in establishing whether observed flood records show evidence of trends or variability in flood frequency, and to determine whether these patterns can be linked to climatic changes. However, the river catchments used in many published studies are influenced by direct human alteration such as reservoir regulation and urbanisation, which can confound the interpretation of climate-driven variability. Furthermore, a majority of previous studies have analysed changes in low magnitude floods, such as the annual peak flow, at a national scale. Few studies are known that have analysed changes in large floods (greater than 25-year floods) on a continental scale. To fill this research gap, we present a study analysing flood flows from reference hydrologic networks (RHNs) or RHN-like gauges across a large study domain embracing North America and much of Europe. RHNs comprise gauging stations with minimally disturbed catchment conditions, which have a near-natural flow regime and provide good quality data; RHN analyses thus allow hydro-climatic variability to be distinguished from direct artificial disturbances or data inhomogeneities. One of the key innovations in this study is the definition of an RHN-like network consisting of 1204 catchments on a continental scale. The network incorporates existing, well-established RHNs in Canada, the US, the UK, Ireland and Norway, alongside RHN-like catchments from Europe (France, Switzerland, Iceland, Denmark, Sweden, Finland, Spain), which have been incorporated in the network following a major effort to ensure RHN-like status of candidate gauges through consultation with local experts. As the aim of the study is to examine

  14. Compilation of Water-Resources Data and Hydrogeologic Setting for the Allison Woods Research Station in Iredell County, North Carolina, 2005-2008

    USGS Publications Warehouse

    Huffman, Brad A.; Abraham, Joju

    2010-01-01

    Water-resources data were collected to describe the hydrologic conditions at the Allison Woods research station near Statesville, North Carolina, in the Piedmont Physiographic Province of North Carolina. Data collected by the U.S. Geological Survey and the North Carolina Department of Environment and Natural Resources, Division of Water Quality, from April 2005 through September 2008 are presented in this report. Data presented include well-construction characteristics and periodic groundwater-level measurements for 29 wells, borehole geophysical logs for 8 wells, hourly groundwater-level measurements for 5 wells, continuous water-quality measurements for 3 wells, periodic water-quality samples for 12 wells and 1 surface-water station, slug-test results for 11 wells, and shallow groundwater-flow maps. In addition, the geology and hydrogeology at the site are summarized.

  15. Analysis of land use changes over the last 200 years in the catchment of Lake Czechowskie (Pomerania, northern Poland)

    NASA Astrophysics Data System (ADS)

    Tyszkowski, Sebastian; Kaczmarek, Halina

    2014-05-01

    Changes in land cover in the catchment area are, beside climate change, some of the major factors affecting sedimentation processes in lakes. With increasing human impact, changes in land cover no longer depend primarily on climate. In relation to research on sediments of Lake Czechowskie in Pomeranian Province in North Poland, land use changes over the last 200 years were analysed, with particular reference to deforestation or afforestation. The study area was the lake catchment, which covers nearly 20 km2. The analysis was based on archival and contemporary cartographic and photogrammetric materials, georeferenced and rectified using ArcGIS software. The following materials were used: Schrötter-Engelhart, Karte von Ost-Preussen nebst Preussisch Litthauen und West-Preussen nebst dem Netzdistrict, 1:50 000, section 92, 93, 1796-1802; Map Messtishchblatt, 1:25000, sheet Czarnen, (mapping conducted in 1874), 1932; Map WIG (Military Geographical Institute - Wojskowy Instytut Geograficzny), 1:25000, sheet Osowo, (mapping conducted in 1929-31), 1933; aerial photos 1:13000, 1964, 1969; 1:25000, 1987; 1:26000, 1997; aerial ortophotomap , 1:5000, 2010. Today, over 60% of the catchment of Lake Czechowskie is covered with forests, dominated by planted Scots pine (Pinus sylvestris), while the remaining areas are used for agricultural purposes or are built up. The first cartographic materials indicate that in the late 18th c., forest covered almost 50% of the catchment surface. By the year 1870, there was a significant reduction in the forested area, as its contribution fell to 40%. Deforestation took place mainly between the main villages. In the 1920s the forest cover increased to 44%. Today, almost the entire lake is surrounded by forest and a wetland belt (at least 0.5 km wide). Deforestation in the catchment should not be attributed solely to logging because the area of Tuchola Forests (Bory Tucholskie) was repeatedly affected by natural disasters. In the 19th c. these

  16. Doing hydrology backwards in tropical humid catchments

    NASA Astrophysics Data System (ADS)

    Real Rangel, R.; Brena-Naranjo, J. A.; Pedrozo-Acuña, A.

    2015-12-01

    Top-down approaches in hydrology offer the possibility to predict water fluxes at the catchment scale based on the interpretation of the observed hydrological response at the catchment itself. Doing hydrology backwards (inferring precipitation and evapotranspiration rates at the catchment scale from streamflow measurements, see Kirchner (2009)) can be a useful methodology for estimating water fluxes at the catchment and regional scales. Previous studies using this inverse modeling approach have been performed in regions (UK, Switzerland, France, Eastern US) where energy-limited (in winter and early spring) and water-limited conditions (in summer) prevail during a large period of the year. However, such approach has not been tested in regions characterized by a quasi-constant supply of water and energy (e.g. humid tropics). The objective of this work is to infer annual rates of precipitation and evapotranspiration over the last decade in 10 catchments located in Mexico's tropical humid regions. Hourly discharge measurements during recession periods were analyzed and parameters for the nonlinear storage-discharge relationship of each catchment were derived. Results showed large variability in both catchment-scale precipitation and evapotranspiration rates among the selected study sites. Finally, a comparison was done between such estimates and those obtained from remotely-sensed data (TRMM for precipitation and MOD16 for evapotranspiration).

  17. Catchment water storage: Models vs Measurements

    NASA Astrophysics Data System (ADS)

    McMillan, Hilary

    2016-04-01

    Recent years have seen a great deal of progress in development of hydrological models that can simulate both the dynamic streamflow response and the hydrochemical flux response of a catchment. In general terms, streamflow response is driven by water deficit in the catchment, whereas hydrochemical response is driven by water storage. Therefore, models that can simultaneously predict both responses must succeed in representing these two related, but different, quantities. This presentation will consider how much information we can gain from field studies to quantify the joint deficit/storage state of a catchment. In particular, examples from two New Zealand experimental catchments in lowland and high country locations will be used to link typical measurements available with the information required by hydrological - hydrochemical models. I will then use the example catchments to assess how well the structure of a typical hydrological-hydrochemical model is supported by field measurements. In particular, can we quantify catchment storage and link this to flow response? Can we incorporate our knowledge of plant water use into such a model, including timing and depth of water withdrawn by the plant? What can field measurements tell us about spatial variability in hydrological-hydrochemical response and can this be represented in the model? I will conclude by discussing what we can learn from field data about the major challenges ahead in catchment storage modelling.

  18. A biogeochemical comparison of two well-buffered catchments with contrasting histories of acid deposition

    USGS Publications Warehouse

    Shanley, J.B.; Kram, P.; Hruska, J.; Bullen, T.D.

    2004-01-01

    Much of the biogeochemical cycling research in catchments in the past 25 years has been driven by acid deposition research funding. This research has focused on vulnerable base-poor systems; catchments on alkaline lithologies have received little attention. In regions of high acid loadings, however, even well-buffered catchments are susceptible to forest decline and episodes of low alkalinity in streamwater. As part of a collaboration between the Czech and U.S. Geological Surveys, we compared biogeochemical patterns in two well-studied, well-buffered catchments: Pluhuv Bor in the western Czech Republic, which has received high loading of atmospheric acidity, and Sleepers River Research Watershed in Vermont, U.S.A., where acid loading has been considerably less. Despite differences in lithology, wetness, forest type, and glacial history, the catchments displayed similar patterns of solute concentrations and flow. At both catchments, base cation and alkalinity diluted with increasing flow, whereas nitrate and dissolved organic carbon increased with increasing flow. Sulfate diluted with increasing flow at Sleepers River, while at Pluhuv Bor the sulfate-flow relation shifted from positive to negative as atmospheric sulfur (S) loadings decreased and soil S pools were depleted during the 1990s. At high flow, alkalinity decreased to near 100 ??eq L-1 at Pluhuv Bor compared to 400 ??eq L-1 at Sleepers River. Despite the large amounts of S flushed from Pluhuv Bor soils, these alkalinity declines were caused solely by dilution, which was greater at Pluhuv Bor relative to Sleepers River due to greater contributions from shallow flow paths at high flow. Although the historical high S loading at Pluhuv Bor has caused soil acidification and possible forest damage, it has had little effect on the acid/base status of streamwater in this well-buffered catchment. ?? 2004 Kluwer Academic Publishers.

  19. Limnological consequences of climate change in Wisconsin lakes: the North Temperate Lakes Long Term Ecological Research Program (Invited)

    NASA Astrophysics Data System (ADS)

    Stanley, E. H.; Beversdorf, L.; Carpenter, S. R.; Hanson, P. C.; Hsieh, Y. F.; Hunt, R. J.; Kara, E.; Kamarainen, A. M.; Kucharik, C. J.; Lathrop, R. C.; McMahon, K. D.; Miller, T.; Walker, J. F.; Wu, C. H.

    2009-12-01

    The North Temperate Lakes Long-Term Ecological Research Program aims to understand change in lake districts in relation to relevant abiotic, biotic, and human processes. Within this broad mission, investigating the limnological consequences of climate dynamics has been a major research theme for this 25-year project. Here, we report on effects of climate change on dominant regional biogeochemical cycles: carbon in the Northern Highlands Lake District (NHLD) of Northern Wisconsin, and phosphorus in the Yahara Lake district of Southern Wisconsin. Lakes play a significant role in regional C cycling in the NHLD and are net sources to the atmosphere, thus, climate changes that affect lake C dynamics may have important large-scale consequences. Simulation models used to explore scenarios of wet and dry future climates indicate that CO2 fluxes to the atmosphere had the greatest sensitivity to precipitation changes. A wetter climate scenario resulted in a 31% increase in CO2 efflux, reaching an areal rate roughly equal to terrestrial CO2 uptake. In southern Wisconsin lakes, P cycling has been a major research focus because of its role in controlling lake productivity, with excess P inputs commonly leading to eutrophication. In years with extreme precipitation events, runoff P loadings are massive resulting in a high P status for the lake and worse summer blue-green algal blooms. During prolonged droughts when runoff P loadings are low, P concentrations in the lake decline with fewer algal blooms. Climate dynamics also have a major effect on internal P processes via their effects on lake stratification. Duration and stability of summer stratification has increased over the past 50 years, and greater lake stability is correlated with lower epilimnetic P, but higher hypolimnetic P. On balance, this has led to increased water clarity (lower productivity), but may also increase the likelihood of summertime algal blooms through episodic delivery of hypolimnetic P to the

  20. Shale to Regolith Evolution: The Controls on Catchment Solute Fluxes

    NASA Astrophysics Data System (ADS)

    Sullivan, Pamela; Goddéris, Yves; Shi, Yuning; Singha, Kamini; Clarke, Brian; Schott, Jacques; Duff, Chritopher; Brantley, Susan

    2014-05-01

    Understanding the factors that control the formation of regolith and the evolution of pore space within regolith as it is moves upward to the surface is of global importance. Unfortunately, both access and high costs have been prohibitive in gathering information about the bedrock-regolith boundary. Recognizing the need for data at depth, the Critical Zone Observatory (CZO) network initiated the "Drill the Ridge" project. The goal of this project is to investigate fresh bedrock at each CZO and then to perform an array of downhole geophysical survey and geochemical analyses to understand regolith formation. In response to this call, several ridgetop boreholes were drilled at the Susquehanna Shale Hills CZO in 2012 and 2013. Here we present the optical televiewer and gamma logs of these boreholes, along with downcore bulk geochemical analysis to shed light on the geochemical and lithological controls on the evolution of the watershed. Observations of catchment hydrology are also being used with estimates of hydrologic parameters to quantify near-surface geologic evolution and geochemical fluxes associated with weathering at depth. To quantify the contribution of weathering fluxes from the mobile regolith, we then link the meteorological forcing from the North American Land Data Assimilation System (NLDAS-2), the fully-coupled land-surface Penn State Integrated Hydrologic Model (Flux-PIHM), and the geochemical box model WITCH. With this cascade of models, solute fluxes for the CZO are being simulated. At depth, the bulk geochemical analysis of ridgetop sediments indicates that pyrite had the deepest depletion front, which was concurrent with the regional water table position. Hydrologic data together with detailed borehole and bulk soil/rock geochemical analysis elucidated an eastern to western progression in lithology across the SSHCZO catchment controls fracture distribution and thus groundwater flow. Where shale and mudstone underlie the eastern portion of

  1. Evaluation of a distributed catchment scale water balance model

    NASA Technical Reports Server (NTRS)

    Troch, Peter A.; Mancini, Marco; Paniconi, Claudio; Wood, Eric F.

    1993-01-01

    The validity of some of the simplifying assumptions in a conceptual water balance model is investigated by comparing simulation results from the conceptual model with simulation results from a three-dimensional physically based numerical model and with field observations. We examine, in particular, assumptions and simplifications related to water table dynamics, vertical soil moisture and pressure head distributions, and subsurface flow contributions to stream discharge. The conceptual model relies on a topographic index to predict saturation excess runoff and on Philip's infiltration equation to predict infiltration excess runoff. The numerical model solves the three-dimensional Richards equation describing flow in variably saturated porous media, and handles seepage face boundaries, infiltration excess and saturation excess runoff production, and soil driven and atmosphere driven surface fluxes. The study catchments (a 7.2 sq km catchment and a 0.64 sq km subcatchment) are located in the North Appalachian ridge and valley region of eastern Pennsylvania. Hydrologic data collected during the MACHYDRO 90 field experiment are used to calibrate the models and to evaluate simulation results. It is found that water table dynamics as predicted by the conceptual model are close to the observations in a shallow water well and therefore, that a linear relationship between a topographic index and the local water table depth is found to be a reasonable assumption for catchment scale modeling. However, the hydraulic equilibrium assumption is not valid for the upper 100 cm layer of the unsaturated zone and a conceptual model that incorporates a root zone is suggested. Furthermore, theoretical subsurface flow characteristics from the conceptual model are found to be different from field observations, numerical simulation results, and theoretical baseflow recession characteristics based on Boussinesq's groundwater equation.

  2. Pseudo Paired Catchments Analysis to Assess the Impact of Urbanization on Catchment Hydrology

    NASA Astrophysics Data System (ADS)

    Salavati, B.; Oudin, L.; Furusho, C.; Ribstein, P.

    2014-12-01

    Paired catchments analysis provides a robust approach to assess the impact of land use changes on catchment's hydrological response. This approach is limited by the availability of data for two neighbor catchments with and without land use changes under similar climate conditions. Thus, hydrological modelling approaches are also very popular since they do not depend on data of a reference catchment. In the present study, 70 urbanized and non-urbanized paired catchments were selected in the United States. Unit housing density maps over the 1940-2010 time period were used to reconstruct historic impervious area extents with aproximatly the same resolution as the National Land Cover Database (NLCD) maps. Two approaches were compared to assess the impact of urbanization on catchment-scale hydrology: the classical paired catchments approach using observed flow time series and an alternative paired catchments approach involving hydrological modeling that allows to simulate a virtual control catchment. To this aim, the GR4J model, a conceptual daily 4-parameter hydrological model, was used. The parameters of the model calibrated on the pre urbanization period were used to predict the streamflow that would have occurred in the urban catchment if the urbanization had not taken place. Then, classical statistical methods involving ANCOVA were used to detect the significance and to quantify the change on the hydrological responses due to land use changes. Results show that the two approaches lead to similar conclusions on the impact of urbanization on catchment hydrology. Thus, the modelling approach provides a relevant alternative for case studies where data of reference catchments are not available.

  3. Neural networks forecast in small catchments with transfer of network parameters

    NASA Astrophysics Data System (ADS)

    Maca, P.; Havlicek, V.; Hermanovsky, M.; Horacek, S.; Pech, P.

    2009-04-01

    This contribution deals with neural network approach for short term forecast on small catchments. The applied methodology is based on theory of multilayer perceptron (MLP), feed forward neural network with back propagation optimization procedure was tested in order to explore the possibilities to transfer parameters between different catchments. Supervised optimization of network parameters and structure was investigated. A software tool was created for these research and operative purposes. The hourly discharges and rainfall data of real flood events served as an input to MLP. Seven catchments with areas, which range from 10 to 250 square kilometres and which are situated in the east part of the Czech Republic, were selected. The input data were normalized by parametric method. Variable configuration of neural network was tested in number of modes represented by different combination of learning and testing data sets. The analysis focuses on ability of the model to forecast the flood event with different peak discharge magnitudes. This should be achieved in both application steps - MLP learning and testing within given catchment and in step of parameter transfer of well learned network to another catchment. The length of prediction ranged from one hour to six hours ahead. The results showed that the model is capable to provide satisfying short term discharge forecast for the most of studied cases, including successful parameter transfer among different catchments. This was accomplished by using optimization of parameters which determine not only the structure and behaviour of applied network but also the transformation of input data.

  4. Studies in Teaching: 2009 Research Digest. Research Projects Presented at Annual Research Forum (15th, Winston-Salem, North Carolina, December 2009)

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    2009-01-01

    This document presents the proceedings of the Annual Research Forum. Included herein are the following 29 studies: (1) What Factors Influence Algebra 1 Students' Attitudes toward Math? (Elizabeth A. Allen); (2) Low-Income Student and Teacher Impressions of Kagan Cooperative Learning (Andrea Anderson); (3) Developing and Implementing an Articulated…

  5. A Successful Example of Transitioning Research to NCEP Operations: The North American Land Data Assimilation System (NLDAS)

    NASA Astrophysics Data System (ADS)

    Ek, M. B.; Xia, Y.; Wei, H.; Meng, J.; Dong, J.; Mitchell, K.; Wood, E. F.; Sheffield, J.; Peters-Lidard, C. D.; Mocko, D. M.; Cosgrove, B.; Lettenmaier, D. P.; Mo, K. C.; Ebisuzaki, W.; Rosencrans, M.; Luo, L.; Luebehusen, E.

    2014-12-01

    The North American Land Data Assimilation System (NLDAS) is a long-term, multi-institutional project initiated to provide improved land surface initial conditions for weather and climate models, and subsequently expanded to support multiple applications related to land surface hydrology. Begun as a research project in January 2000, it became quasi-operational in September 2008, and operational at NCEP in August 2014. The NLDAS development included Phase 1 to establish the NLDAS configuration, including collection of soil and vegetation data, selection of land-surface models (LSMs), generation of surface forcing data sets, and model runs for a 3-year period, with evaluation/validation of model output. Phase 2 involved 30-year (1979-2008) retrospective and near real-time runs (2009-present) of four improved LSMs and surface forcing to generate energy and water fluxes, and state variables from those LSMs. The anomalies and percentiles from the 30-year climatologies for evapotranspiration, soil moisture, runoff/streamflow, and snow water equivalent have been comprehensively evaluated against observations, and are used to support US operational drought monitoring and prediction tasks such as the U.S. Drought Monitor, NCEP Climate Prediction Center drought information, and activities of the National Integrated Drought Information System. More than 34 years of surface forcing and model output data have been distributed by the NCEP/EMC NLDAS website (www.emc.ncep.noaa.gov/mmb/nldas), the NASA Goddard Earth Sciences Data Information Services Center (GES DISC, daac.gsfc.nasa.gov), the UCAR/NCAR Climate Data Guide (climatedataguide.ucar.edu/climate-data), and the USGS Geo Portal (cida.usgs.gov/gdp). The operational implementation provides more reliable and timely access to NLDAS products. This presentation summarizes experiences of NLDAS, status and format of current NLDAS products, and the future plans for NLDAS.

  6. Aerodynamic and Landing Measurements Obtained During the First Powered Flight of the North American X-15 Research Airplane

    NASA Technical Reports Server (NTRS)

    1960-01-01

    During the first powered flight of the North American X-15 research airplane on September 17, 1959, a Mach number of 2.1 and an altitude of 52,000 feet were attained. Static and dynamic maneuvers were performed to evaluate the characteristics of the airplane at subsonic and supersonic speeds. Data from these maneuvers as well as from the launch and landing phases are presented, discussed, and compared with predicted values. The rate of separation of the X-15 from the B-52 carrier airplane at launch was less than that predicted by wind-tunnel studies and was less rapid than in the lightweight condition of the initial glide flight. In addition, the angular motions and bank angle attained following the launch were of lesser magnitude than in the glide flight. Stable longitudinal-stability trends were apparent during the acceleration to maximum speed, and the pilot reported experiencing little or no transonic trim excursions. An inexplicable high-frequency vibration, which occurred at Mach numbers above 1.4, is being investigated further. Essentially linear lift and stability characteristics were indicated within the limited ranges of angle of attack and angle of sideslip investigated. The dynamic longitudinal and lateral-directional stability and control-effectiveness characteristics appeared satisfactory to the pilot. Although the longitudinal- and lateral-directional-damping ratios showed no significant change from subsonic to supersonic speeds, on the basis of time to damp, the damping characteristics at supersonic speeds appeared to the pilot to be somewhat improved over those at subsonic speeds.

  7. Effects of climate and irrigation changes on the water balance of a Mediterranean catchment

    NASA Astrophysics Data System (ADS)

    von Gunten, Diane; Wöhling, Thomas; Haslauer, Claus; Cirpka, Olaf

    2015-04-01

    Climate change will strongly impact the water cycle of Mediterranean catchments as a result of the changes in precipitation patterns and increased temperature. However, effects of climate change are difficult to predict with precision and are often influenced by land-use or water management choices. In agricultural catchments, irrigation is of particular interest because of its importance for cultivation in semi-arid climate and because of its strong impacts on hydrological processes. Interactions between irrigation and climate change impacts are likely to be important and should be considered when studying the future of a catchment. However, they are still difficult to quantify. A better understanding of the differences in climate-change sensitivity between irrigated and non-irrigated catchments would allow a finer description of local climate change effects. In this study, we compared the impacts of climate change in various irrigation scenarios, including a scenario without irrigation. Our case study was a relatively small catchment (about 7.5km2) in north-east Spain, called the Lerma catchment. This catchment was not irrigated prior to 2006, but 54% of its surface is now used for irrigated agriculture. This transition to irrigated agriculture was closely monitored and data on hydraulic heads, discharge and daily irrigation volume are available. Based on these measurements, a coupled surface-subsurface model of the catchment was developed using the pde-based model HydroGeoSphere. The model performs well for both irrigated and non-irrigated periods. Future climate was predicted using four regional climate models from the ENSEMBLE project (P.van der Linden and J.Mitchell, ENSEMBLES: Climate Change and its Impacts [...], Met Office Hadley Center, 2009) and two downscaling methods, including one based on a weather generator. Four irrigation scenarios, based on projected potential evapotranspiration changes, were compared. Our results show a shift in the climate

  8. Understanding the Importance of Aspect on Mountain Catchment Hydrology

    NASA Astrophysics Data System (ADS)

    Broxton, P. D.; Troch, P. A.; Lyon, S. W.

    2008-12-01

    In surface hydrology, much attention is paid to the effects of changing water fluxes, however there is less of a focus on the effects of changing energy fluxes. These energy fluxes are an important driver of many hydrological processes such as evapotranspiration and snow sublimation/ablation. To test the hypothesis that varying energy fluxes are important to the hydrological features of a catchment, we have designed an experiment that involves calculating mean transit times for a number of catchments that drain from a large dome located in the Valles Caldera, New Mexico, called Redondo Peak. These catchments have different orientations and therefore receive different amounts of solar radiation. We found that there is a general correlation between mean transit times and aspect, suggesting that in the Valles Caldera, transit times might be affected by a variety of features that are influenced by exposure to solar radiation, such as slope steepness, vegetation patterns, and soil depth. We also used a distributed model to to simulate a number of factors simultaniously to determine how hydrological features are influenced by aspect. These efforts have illuminated differences in energy inputs, the timing and intensity of snowmelt, and soil moisture patterns. The purpose of this research is to further refine a conceptual model that combines the net effect of these various factors and contribute to the body of scientific knowledge describing the movement of water in hillslopes.

  9. Restoring Landform Geodiversity in Modified Rivers and Catchments

    NASA Astrophysics Data System (ADS)

    Smith, Ben; Clifford, Nicholas

    2014-05-01

    Extensive human modification and exploitation has created degraded and simplified systems lacking many of the landforms which would characterise healthy, geodiverse rivers. As awareness of geodiversity grows we must look to ways not only to conserve geodiversity but to also restore or create landforms which contribute to geodiverse environments. River restoration, with lessons learned over the last 30 years and across multiple continents, has much to offer as an exemplar of how to understand, restore or create geodiversity. Although not mentioned explicitly, there is an implicit emphasis in the Water Framework Directive on the importance of landforms and geodiversity, with landform units and assemblages at the reach scale assumed to provide the physical template for a healthy aquatic ecosystem. The focus on hydromorphology has increased the importance of geomorphology within river restoration programmes. The dominant paradigm is to restore landforms in order to increase habitat heterogeneity and improve biodiversity within rivers. However, the process of landform restoration is also a goal in its own right in the context of geodiversity, and extensive compilations of restoration experiences allow an inventory and pattern of landform (re-) creation to be assembled, and an assessment of landform function as well as landform presence/absence to be made. Accordingly, this paper outlines three principal research questions: Which landforms are commonly reinstated in river restoration activities? How do these landforms function compared to natural equivalents and thus contribute to 'functional' geodiversity as compared to the 'aesthetic' geodiversity? How does landform diversity scale from reach to catchment and contribute to larger-scale geodiversity? Data from the UK National River Restoration Inventory and the RHS are combined to assess the frequency and spatial distribution of commonly created landforms in relation to catchment type and more local context. Analysis is

  10. Tracing crop-specific sediment sources in agricultural catchments

    NASA Astrophysics Data System (ADS)

    Blake, William H.; Ficken, Katherine J.; Taylor, Philip; Russell, Mark A.; Walling, Desmond E.

    2012-02-01

    A Compound Specific Stable Isotope (CSSI) sediment tracing approach is evaluated for the first time in an agricultural catchment setting against established geochemical fingerprinting techniques. The work demonstrates that novel CSSI techniques have the potential to provide important support for soil resource management policies and inform sediment risk assessment for the protection of aquatic habitats and water resources. Analysis of soil material from a range of crop covers in a mixed land-use agricultural catchment shows that the carbon CSSI signatures of particle-reactive fatty acids label surface agricultural soil with distinct crop-specific signatures, thus permitting sediment eroded from each land-cover to be tracked downstream. High resolution sediment sampling during a storm event and analysis for CSSI and conventional geochemical fingerprints elucidated temporal patterns of sediment mobilisation under different crop regimes and the specific contribution that each crop type makes to downstream sediment load. Pasture sources (65% of the catchment area) dominated the sediment load but areal yield (0.13 ± 0.02 t ha - 1 ) was considerably less than that for winter wheat (0.44 ± 0.15 t ha - 1 ). While temporal patterns in crop response matched runoff and erosion response predictions based on plot-scale rainfall simulation experiments, comparison of biomarker and geochemical fingerprinting data indicated that the latter overestimated cultivated land inputs to catchment sediment yield due to inability to discriminate temporary pasture (in rotation) from cultivated land. This discrepancy, however, presents an opportunity since combination of the two datasets revealed the extremely localised nature of erosion from permanent pasture fields in this system (estimated at up to 0.5 t ha - 1 ). The novel use of CSSI and geochemical tracers in tandem provided unique insights into sediment source dynamics that could not have been derived from each method alone. Research

  11. Using isotopes to investigate hydrological flow pathways and sources in a remote Arctic catchment

    NASA Astrophysics Data System (ADS)

    Lessels, Jason; Tetzlaff, Doerthe; Dinsmore, Kerry; Street, Lorna; Billet, Mike; Baxter, Robert; Subke, Jens-Arne; Wookey, Phillip

    2014-05-01

    Stable water isotopes allow for the identification of flow paths and stream water sources. This ability is beneficial in improving the understanding in catchments with dynamic spatial and temporal sources. Arctic catchments are characterised with strong seasonality where the dominant flow paths change throughout the short summer season. Therefore, the identification of stream water sources through time and space is necessary in order to accurately quantify these dynamics. Stable isotope tracers are incredibly useful tools which integrate processes of time and space and therefore, particularly useful in identifying flow pathways and runoff sources at remote sites. This work presents stable isotope data collected from a small (1km2) catchment in Northwest Canada. The aims of this study are to 1) identify sources of stream water through time and space, 2) provide information which will be incorporated into hydrological and transit time models Sampling of snowmelt, surface runoff, ice-wedge polygons, stream and soil water was undertaken throughout the 2013 summer. The results of this sampling reveal the dominant flow paths in the catchment and the strong influence of aspect in controlling these processes. After the spring freshet, late lying snow packs on north facing slopes and thawing permafrost on south facing slopes are the dominant sources of stream water. Progressively through the season the thawing permafrost and precipitation become the largest contributing sources. The depth of the thawing aspect layer and consequently the contribution to the stream is heavily dependent on aspect. The collection of precipitation, soil and stream isotope samples throughout the summer period provide valuable information for transit time estimates. The combination of spatial and temporal sampling of stable isotopes has revealed clear differences between the main stream sources in the studied catchment and reinforced the importance of slope aspect in these catchments.

  12. Projected Climate Change Impacts on a Mediterranean Catchment under Different Irrigation Scenarios

    NASA Astrophysics Data System (ADS)

    Gunten, D. V.; Wöhling, T.; Haslauer, C. P.; Cirpka, O. A.

    2014-12-01

    In semi-arid regions, irrigation is often needed for cultivation and greatly impacts the water cycle of agricultural catchments. It is important to investigate the effects of climate change in these settings under consideration of future agricultural management and irrigation needs. However, quantifying how irrigation influences climate-change effects is still a challenge. Understanding the differences in climate-change sensitivity between irrigated and non-irrigated catchments would allow refining regional-scale assessments of climate-change impacts. We investigated a catchment in north-east Spain which had not been irrigated prior to 2006 and where 54% of the land is now converted to irrigated agriculture. Data on hydraulic heads, discharge, and irrigation were used to simulate coupled surface-subsurface flow in the catchment, using the pde-based model HydroGeoSphere. The model performs well for both irrigated and non-irrigated periods. To predict future climate scenarios in the region, we use four regional climate models from the ENSEMBLE project (P.van der Linden and J.Mitchell, ENSEMBLES: Climate Change and its Impacts [...], Met Office Hadley Center, 2009) and three downscaling methods. We further investigated four irrigation scenarios, based on projected potential evapotranspiration. Preliminary results show a shift in the hydrological regime of the catchment under future climate scenarios. Under irrigation, the variability of low-flow discharge increases in future climate. On the contrary, peak flows increase and hydraulics heads decrease significantly in the non-irrigated scenarios. For example, annual maximum flow increases by about 15 % in the non-irrigated case but there is only little change in the corresponding irrigated scenarios. Sensitivity to projected precipitation changes is higher without irrigation, while potential evapotranspiration has more importance for irrigated catchments.

  13. Contrasting Patterns of Fine Fluvial Sediment Delivery in Two Adjacent Upland Catchments

    NASA Astrophysics Data System (ADS)

    Perks, M.; Bracken, L.; Warburton, J.

    2010-12-01

    Quantifying patterns of fine suspended sediment transfer in UK upland rivers is of vital importance in combating the damaging effects of elevated fluxes of suspended sediment, and sediment associated transport of contaminants, on in-stream biota. In many catchments of the UK there is still a lack of catchment-wide understanding of both the spatial patterns and temporal variation in fine sediment delivery. This poster describes the spatial and temporal distribution of in-stream fine sediment delivery from a network of 44 time-integrated mass flux samplers (TIMs) in two adjacent upland catchments. The two catchments are the Esk (210 km2) and Upper Derwent (236 km2) which drain the North York Moors National Park. Annual suspended sediment loads in the Upper Derwent are 1273 t, whereas in the Esk catchment they are greater at 1778 t. Maximum yields of 22 t km-2 yr -1 were measured in the headwater tributaries of the Rye River (Derwent), whereas peak yields in the Esk are four times greater (98 t km-2 yr-1) on the Butter Beck subcatchment. Analysis of the within-storm sediment dynamics, indicates that the sediment sources within the Upper Derwent catchment are from distal locations possibly mobilised by hillslope runoff processes, whereas in the Esk, sediment sources are more proximal to the channel e.g. within channel stores or bank failures. These estimates of suspended sediment flux are compared with the diffuse pollution potential generated by a risk-based model of sediment transfer (SCIMAP) in order to assess the similarity between the model predictions and observed fluxes.

  14. A differential equation for specific catchment area

    NASA Astrophysics Data System (ADS)

    Gallant, John C.; Hutchinson, Michael F.

    2011-05-01

    Analysis of the behavior of specific catchment area in a stream tube leads to a simple nonlinear differential equation describing the rate of change of specific catchment area along a flow path. The differential equation can be integrated numerically along a flow path to calculate specific catchment area at any point on a digital elevation model without requiring the usual estimates of catchment area and width. The method is more computationally intensive than most grid-based methods for calculating specific catchment area, so its main application is as a reference against which conventional methods can be tested. This is the first method that provides a benchmark for more approximate methods in complex terrain with both convergent and divergent areas, not just on simple surfaces for which analytical solutions are known. Preliminary evaluation of the D8, M8, digital elevation model networks (DEMON), and D∞ methods indicate that the D∞ method is the best of those methods for estimating specific catchment area, but all methods overestimate in divergent terrain.

  15. Building learning catchments for integrated catchment managing: designing learning systems based on experiences in the UK and South Africa.

    PubMed

    Collins, Kevin; Colvin, John; Ison, Ray

    2009-01-01

    We examine challenges and opportunities for developing 'learning systems' for integrated catchment managing (ICMg) drawing on our experiences in two contexts: UK and South Africa (SA). Our research question is: what is it that we would have to experience to claim that a catchment was a learning catchment? We suggest that any valid answer to this question will arise in social relations in context-determined ways. From this perspective ICMg is an emergent 'performance' of stakeholders engaged in mutual action, or social learning (SL), in which understandings and practices are transformed in situation improving ways. These questions are relevant given recent reviews suggesting that implementation of the European Water Framework Directive (WFD) is not nurturing adaptive management. Our European and SA experiences demonstrate that it is possible to invest in social learning as a governance mechanism for water managing, but key constraints exist. Our SA work based on (i) appreciating the situation, especially the history, and (ii) contextual appreciation and design of learning systems (as a result of (i)) is described in response to these constraints. We conclude that more attention on developing an effective praxis for ICMg is required. PMID:19237762

  16. Do physicochemical sediment variables and their soft sediment macrofauna differ among microsize coastal lagoons with forested and urbanised catchments?

    NASA Astrophysics Data System (ADS)

    Mikac, K. M.; Maher, W. A.; Jones, A. R.

    2007-03-01

    Microsize intermittently open and closed coastal lagoons are a common feature of the coast of southern New South Wales, in southeast Australia. Many of these lagoons are undergoing development and urbanisation of their catchments, leading to concern about their ecological health. Consequently, it was hypothesised that lagoons with urbanised catchments should hav e finer, more contaminated sediments and fewer macrofaunal taxa (represented by opportunistic taxa) than lagoons that have undeveloped, forested catchments. To test these hypotheses, five lagoons with catchments dominated by either native forest or urban development were compared with respect to their sediment composition (i.e. sediment grain size, trace metal concentrations, organic carbon and nutrients) and soft sediment macrofaunal assemblages in the Batemans Bay region of southeast Australia. Using a nested design without temporal replication, replicate core samples were taken from sampling stations nested within lagoons that were nested within catchment type. Univariate and multivariate statistical analyses were used to test for significant differences and dissimilarities between catchment types and among lagoons. Of all the abiotic and biotic variables measured, only total nitrogen showed a difference between the two catchment types. Thus providing support to refute the explanatory model that urbanisation had negatively affected the sedimentary environment and macrofaunal composition of these microsize coastal lagoons. In contrast, differences among lagoons were usually significant with differences between the two forested lagoons, North Head and Acheron lagoon, being particularly large for assemblage composition and the abundance of some taxa; this variation may, potentially, obscure any effects of urbanisation. In addition, the information collected in this study provides a basic understanding of the physicochemical and biological aspects of microsize coastal lagoons in southeast Australia. Such

  17. A novel modeling framework to obtain new insights into the controls of catchment mixing processes

    NASA Astrophysics Data System (ADS)

    Neubauer, Markus; Musolff, Andreas; de Rooij, Gerrit; Fleckenstein, Jan H.

    2015-04-01

    der Velde, Y., P. Torfs, S. van der Zee, and R. Uijlenhoet. 2012 "Quantifying Catchment-scale Mixing and Its Effect on Time-varying Travel Time Distributions." Water Resources Research 48 (6): W06536. Botter, G., E. Bertuzzo, and A. Rinaldo. 2011. "Catchment Residence and Travel Time Distributions: The Master Equation." Geophysical Research Letters 38 (11): L11403

  18. Catchment scale molecular composition of hydrologically mobilized dissolved organic matter

    NASA Astrophysics Data System (ADS)

    Raeke, Julia; Lechtenfeld, Oliver J.; Oosterwoud, Marieke R.; Bornmann, Katrin; Tittel, Jörg; Reemtsma, Thorsten

    2016-04-01

    Increasing concentrations of dissolved organic matter (DOM) in rivers of temperate catchments in Europe and North Amerika impose new technical challenges for drinking water production. The driving factors for this decadal increase in DOM concentration are not conclusive and changes in annual temperatures, precipitation and atmospheric deposition are intensely discussed. It is known that the majority of DOM is released by few but large hydrologic events, mobilizing DOM from riparian wetlands for export by rivers and streams. The mechanisms of this mobilization and the resulting molecular composition of the released DOM may be used to infer long-term changes in the biogeochemistry of the respective catchment. Event-based samples collected over two years from streams in three temperate catchments in the German mid-range mountains were analyzed after solid-phase extraction of DOM for their molecular composition by ultra-high resolution mass spectrometry (FT-ICR MS). Hydrologic conditions, land use and water chemistry parameters were used to complement the molecular analysis. The molecular composition of the riverine DOM was strongly dependent on the magnitude of the hydrologic events, with unsaturated, oxygen-enriched compounds being preferentially mobilized by large events. This pattern is consistent with an increase in dissolved iron and aluminum concentrations. In contrast, the relative proportions of nitrogen and sulfur bearing compounds increased with an increased agricultural land use but were less affected by the mobilization events. Co-precipitation experiments with colloidal aluminum showed that unsaturated and oxygen-rich compounds are preferentially removed from the dissolved phase. The precipitated compounds thus had similar chemical characteristics as compared to the mobilized DOM from heavy rain events. Radiocarbon analyses also indicated that this precipitated fraction of DOM was of comparably young radiocarbon age. DOM radiocarbon from field samples

  19. Comparing Hydrologic Response Times Between a Forested and Mountaintop Mined Catchment

    NASA Astrophysics Data System (ADS)

    Miller, A. J.; Zegre, N.

    2012-12-01

    Mountaintop removal mining (MTR) represents the largest land cover/landuse change in the Central Appalachian region. By 2012, the U.S. EPA estimates that MTR will have impacted approximately 6.8% of the predominately forested Appalachian Coalfield region of West Virginia, Kentucky, Tennessee, and Virginia with nearly 4,000 miles of headwater streams buried under valley fills. In spite of the scale and extent of MTR, its hydrologic impacts are poorly understood. While MTR has a well-established pattern of downstream water quality degradation, its effect on the quantity and timing of catchment runoff is less clear. Several devastating floods in the region have been attributed to MTR, but there is little evidence to either confirm or refute this belief. Existing research has focused on statistical analysis of catchment outlet responses, but results from these studies only offer evidence of differences in hydrologic behavior, not process understanding of how the system is changing. This study begins to address that research gap by exploring differences in hydrologic response times, a fundamental hydraulic parameter that controls the conversion of rainfall to runoff. A simple rainfall-runoff model was used to quantify differences in response times for storm events in a mined and predominantly forested catchment. Results showed that the mountaintop mined catchment responded more quickly to storm events than the forested catchment. The mined catchment also showed more variability in response time than the forested catchment. These patterns repeated using multiple model structures. The more rapid response of the mined catchment is likely attributed to increased impervious surface, preferential flow paths within valley fills that rapidly route water to the stream, or rapid displacement of water stored in valley fills upon the onset of rain. However, further research using tools such as isotope tracers is needed to offer insight about the processes responsible for streamflow

  20. Geological controls on isotopic signatures of streamflow: results from a nested catchment experiment in Luxembourg (Europe)

    NASA Astrophysics Data System (ADS)

    Pfister, Laurent; McDonnell, Jeffrey J.; Hissler, Christophe; Martinez-Carreras, Nuria; Gourdol, Laurent; Klaus, Julian; François Iffly, Jean; Barnich, François; Stewart, Mike K.

    2014-05-01

    permeable bedrock, isotopic signatures of streamflow remained stable throughout the entire flow duration curve consistent with a large storage and mixing potential. On less permeable bedrock substrate, we have observed that isotopic signatures in streamflow were much more variable, due to reduced storage volume and comparatively smaller mixing potential. Other metrics such as catchment size and flowpath length exerted a smaller secondary control on isotopic signatures of streamflow in the Alzette River sub-basins. Tague, C., Grant, G.E., 2004. A geological framework for interpreting the low-flow regimes of Cascade streams, Willamette River Basin, Oregon. Water Resources Research, 40(4), doi:10.1029/2003WR002629 Sayama, T., McDonnell, J.J., Dhakal, A., Sullivan, K., 2011. How much water can a watershed store ? Hydrological Processes 25, 3899-3908. Klaus, J., McDonnell, J.J., 2013. Hydrograph separation using stable isotopes: Review and evaluation. Journal of Hydrology 505, 47-64.

  1. Controls on variability in surface and ground waters in a headwater catchment

    NASA Astrophysics Data System (ADS)

    McMillan, Hilary; Srinivasan, MS

    2014-05-01

    Hydrologists recognise the importance of vertical drainage and deep flow paths in runoff generation, even in headwater catchments. Therefore, characterisation of the joint surfacewater-groundwater system is needed to improve hydrological understanding and model representation. Both soil and groundwater stores are highly variable over multiple scales, and the distribution of water has a strong control on flow rates and timing. In this study, we instrumented an upland headwater catchment in New Zealand to measure the spatial variation in unsaturated and saturated-zone responses. Over a period of 16 months we measured continuous soil moisture at 32 locations and near-surface water table (< 2 m) at 14 locations, with varied aspects, hillslope position and distance from stream, as well as recording streamflow at 3 gauges. In this presentation we describe the controls, types and implications of variability. Our results showed several distinct causes of variability in water stores. Some types of variability involve a response of only part of the catchment to a rainfall event, e.g. partial response of deep soils in the summer months. Other types of variability involve differences in dynamics, e.g. recession shapes; or differences in response rates in different parts of the catchment, e.g. timing of winter wet-up, and a distinctive split between slow and fast groundwater responses. A further type of variability occurs when some parts of the catchment respond more strongly than others, as in the partial saturation responses seen in winter. Soil moisture and water table show different variability characteristics. Soil moisture on the North facing slope is qualitatively different to that on the South facing slope: it does not have the long winter plateau seen on the South facing slope. Groundwater variability appears to be more location specific, with both North and South facing slopes showing a combination of fast and slow water table responses to rainfall events. The many

  2. Policy Fuzz and Fuzzy Logic: Researching Contemporary Indigenous Education and Parent-School Engagement in North Australia

    ERIC Educational Resources Information Center

    Lea, Tess; Thompson, Helen; McRae-Williams, Eva; Wegner, Aggie

    2011-01-01

    "Engagement" is the second of six top priorities in Australia's most recent Indigenous education strategy to "close the gap" in schooling outcomes. Drawing on findings from a three-year ethnographic analysis of school engagement issues in the north of Australia, this article situates engagement within the history of Indigenous education policy,…

  3. "Making Connections" at the University of North Carolina: Moving toward a Global Curriculum at a Flagship Research University

    ERIC Educational Resources Information Center

    Smith, Jay M.; Kruse, Julia

    2009-01-01

    The University of North Carolina at Chapel Hill has reformed its undergraduate curriculum to create connections across disciplines and advance efforts to internationalize its campus. As a result, global issues, experiential learning, study abroad, and international course clusters have become an integral part of a curriculum that emphasizes…

  4. Model for Small Business Management Program in North Dakota Post-Secondary Institutions. Final Report. Research Series Number 51.

    ERIC Educational Resources Information Center

    Lake Region Junior Coll., Devils Lake, ND.

    To educate the small business entrepreneur on a continuing basis over three years, a model was developed to meet the specific needs of North Dakota business entrepreneurs and the educational institutions serving them. Enrollment in the program at Lake Region Junior College was limited the first year to twenty businesses and was increased the…

  5. A Comparative Economic Analysis of North-Central New Mexico. New Mexico Agricultural Experiment Station Research Report 211.

    ERIC Educational Resources Information Center

    Carruthers, Garrey E.; Eastman, Clyde

    North-Central New Mexico has many of the problems common to other rural areas. Unemployment and underemployment rates tend to be high and per capita income relatively low. This study evaluated regional economic performance over a 19-year period (1949-1968) as compared to other regions and the nation. Shift analysis (a means of examining regional…

  6. Report Card on Enrollment Projections and Other Selected Papers. Third Annual Meeting of the North Carolina Association for Institutional Research.

    ERIC Educational Resources Information Center

    Brown, Charles I., Ed.

    The major theme of Report Card 1 is enrollment projections. Reports in this section include: Barwick and Stafford's "Statewide Enrollment Projections for North Carolina, 1975-80"; Reiman's "Assumption-Based Model for Developing Institutional Enrollment Projections"; Rajasekhara's "Enrollment Projection," dealing with alternative methods;…

  7. Addressing Retention through an Orientation Course: Results from a North Campus Study. Research Report No. 87-24.

    ERIC Educational Resources Information Center

    Belcher, Marcia J.; And Others

    In 1984-85, Miami-Dade Community College's (MDCC's) North Campus developed a one-credit orientation course (SLS 1101) to provide students with information and college-level skills before they encounter problems. A study was conducted to assess the effectiveness of SLS 1101 in reducing attrition and increasing grade point average (GPA) over the…

  8. Evaluation of White Shield School, Roseglen, North Dakota. Part B: Appendix. Research and Evaluation Report Series No. 30-B.

    ERIC Educational Resources Information Center

    Bureau of Indian Affairs (Dept. of Interior), Albuquerque, NM.

    As an appendix to "Evaluation of White Shield School, Roseglen, North Dakota. Part A", August 1974, this document substantiated findings of an evaluation team. A brief on-site visitation report stated that students wanted more flexible course requirements and firmer student discipline; teachers wanted more authority clarification on discipline…

  9. Evaluation of White Shield School, Roseglen, North Dakota. Part A: Evaluation Report. Research and Evaluation Report Series No. 30-A.

    ERIC Educational Resources Information Center

    Matsushige, Susan, Comp.

    In response to a request from concerned Indian members of the community of Roseglen, North Dakota, an evaluation team visited White Shield School (an elementary/secondary school of 303 students, 50 percent Indian) on May 13-17, 1974 to survey: identification and classification of goals, objectives, and purposes; distinguishing between perceptions…

  10. Groundwater as an emergency source for drought mitigation in the Crocodile River catchment, South Africa

    NASA Astrophysics Data System (ADS)

    Mussá, F. E. F.; Zhou, Y.; Maskey, S.; Masih, I.; Uhlenbrook, S.

    2014-03-01

    Global climate change has received much attention worldwide in the scientific as well as in the political community, indicating that changes in precipitation, extreme droughts and floods may threaten increasingly many regions. Drought is a natural phenomenon that may cause social, economical and environmental damages to the society. In this study, we assess the drought intensity and severity and the groundwater potential to be used as a supplement source of water to mitigate drought impacts in the Crocodile River catchment, a water-stressed sub-catchment of the Incomati River catchment in South Africa. The research methodology consists mainly of three parts. First, the spatial and temporal variation of the meteorological and hydrological drought severity and intensity over the catchment were evaluated. The Standardized Precipitation Index (SPI) was used to analyse the meteorological drought and the Standardized Runoff Index (SRI) was used for the hydrological drought. Second, the water deficit in the catchment during the drought period was computed using a simple water balance method. Finally, a groundwater model was constructed in order to assess the feasibility of using groundwater as an emergency source for drought impact mitigation. Results show that the meteorological drought severity varies accordingly with the precipitation; the low rainfall areas are more vulnerable to severe meteorological droughts (lower and upper crocodile). Moreover, the most water stressed sub-catchments with high level of water uses but limited storage, such as the Kaap located in the middle catchment and the Lower Crocodile sub-catchments are those which are more vulnerable to severe hydrological droughts. The analysis of the potential groundwater use during droughts showed that a deficit of 97 Mm3 yr-1 could be supplied from groundwater without considerable adverse impacts on the river base flow and groundwater storage. Abstraction simulations for different scenarios of extremely

  11. Groundwater as an emergency source for drought mitigation in the Crocodile River catchment, South Africa

    NASA Astrophysics Data System (ADS)

    Mussá, F. E. F.; Zhou, Y.; Maskey, S.; Masih, I.; Uhlenbrook, S.

    2015-02-01

    Global climate change has received much attention worldwide in the scientific as well as in the political community, indicating that changes in precipitation, extreme droughts and floods may increasingly threaten many regions. Drought is a natural phenomenon that causes social, economical and environmental damage to society. In this study, we assess the drought intensity and severity and the groundwater potential to be used as a supplementary source of water to mitigate drought impacts in the Crocodile River catchment, a water-stressed sub-catchment of the Incomati River catchment in South Africa. The research methodology consists of three parts. First, the spatial and temporal variation of the meteorological and hydrological drought severity and intensity over the catchment were evaluated. The Standardized Precipitation Index (SPI) was used to analyse the meteorological drought and the Standardized Runoff Index (SRI) was used for the hydrological drought. Second, the water deficit in the catchment during the drought period was computed using a simple water balance method. Finally, a groundwater model was constructed in order to assess the feasibility of using groundwater as an emergency source for drought impact mitigation. Results show that the low-rainfall areas are more vulnerable to severe meteorological droughts (lower and upper crocodile). Moreover, the most water stressed sub-catchments with high level of water uses but limited storage, such as the Kaap located in the middle catchment and the Lower Crocodile sub-catchments, are more vulnerable to severe hydrological droughts. The analysis of the potential groundwater use during droughts showed that a deficit of 97 Mm3 yr-1 could be supplied from groundwater without considerable adverse impacts on the river base flow and groundwater storage. Abstraction simulations for different scenarios of extremely severe droughts reveal that it is possible to use groundwater to cope with the droughts in the catchment

  12. Compilation of water-resources data and hydrogeologic setting for four research stations in the Piedmont and Blue Ridge physiographic provinces of North Carolina, 2000-2004

    USGS Publications Warehouse

    Huffman, Brad A.; Pfeifle, Cassandra A.; Chapman, Melinda J.; Bolich, Richard E.; Campbell, Ted R.; Geddes, Donald J., Jr.; Pippin, Charles G.

    2006-01-01

    Water-resources data were collected to describe the hydrologic conditions at four research stations in the Piedmont and Blue Ridge Physiographic Provinces of North Carolina. Data collected by the U.S. Geological Survey and the North Carolina Department of Environment and Natural Resources, Division of Water Quality, from September 2000 through September 2004 are presented in this report. The locations and periods of data collection are as follows: the Lake Wheeler Road research station (Raleigh) from April 2001 to September 2004, the Langtree Peninsula research station (Mooresville) from September 2000 to September 2004, the Upper Piedmont research station (Reidsville) from March 2002 to September 2004, and the Bent Creek research station (Asheville) from July 2002 to September 2004. Data presented in this report include well-construction characteristics for 110 wells, periodic ground-water-level measurements for 96 wells, borehole geophysical logs for 23 wells, hourly ground-water-level measurements for 12 wells, continuous-stage measurements for 2 streams, continuous water-quality measurements for 8 wells and 2 streams, periodic water-quality samples for 57 wells and 6 stream sites, slug-test results for 38 wells, and shallow ground-water-flow maps. In addition, the geology and hydrogeology at each site are summarized.

  13. Apportioning sediment pressures on watercourses in grassland dominated agricultural catchments: a new framework for policy support

    NASA Astrophysics Data System (ADS)

    Collins, A.; Black, K.; Walling, D. E.; Wilson, P.

    2009-04-01

    Much of the effort directed towards monitoring and understanding soil erosion in the UK has focused upon arable farming systems, but the evidence base has suggested for some time that soil loss from grassland dominated landscapes can be enhanced by agricultural practises. Studies using composite source fingerprinting procedures have, for example, repeatedly highlighted the relative significance of managed pasture as a sediment source at catchment scale. Although traditional sediment sourcing approaches provide useful generic information for characterising sediment pressures, Catchment Officers working as part of the England Catchment Sensitive Farming Delivery Initiative (ECSFDI) also require higher resolution evidence to assist better the targeting of mitigation options. Accordingly, a new framework combining conventional sediment source fingerprinting and a dual signature tracking method has recently been tested in a grassland catchment in Cumbria, north-west England. The former provides information on the relative significance of generic sediment sources such as grassland or arable surface soils, damaged road verges and channel banks/subsurface sources, whereas the latter elucidates sediment loss from poached gateways or cattle tracks and wider areas of general hoofing damage in grass fields. Uncertainty and prior information are explicitly recognised by the novel framework.

  14. Distribution and diversity of fungi in freshwater sediments on a river catchment scale

    PubMed Central

    Liu, Jie; Wang, Jianan; Gao, Guanghai; Bartlam, Mark G.; Wang, Yingying

    2015-01-01

    Fungal communities perform essential functions in biogeochemical cycles. However, knowledge of fungal community structural changes in river ecosystems is still very limited. In the present study, we combined culture-dependent and culture-independent methods to investigate fungal distribution and diversity in sediment on a regional scale in the Songhua River catchment, located in North-East Asia. A total of 147 samples over the whole river catchment were analyzed. The results showed that compared to the mainstream, the tributaries have a higher fungal community organization and culturable fungal concentration, but possess lower community dynamics as assessed by denaturing gradient gel electrophoresis (DGGE). Furthermore, phylogenetic analysis of DGGE bands showed that Ascomycota and Basidiomycota were the predominant community in the Songhua River catchment. Redundancy analysis revealed that longitude was the primary factor determining the variation of fungal community structure, and fungal biomass was mainly related to the total nutrient content. Our findings provide new insights into the characteristics of fungal community distribution in a temperate zone river at a regional scale, and demonstrate that fungal dispersal is restricted by geographical barriers in a whole river catchment. PMID:25954259

  15. CAOS: the nested catchment soil-vegetation-atmosphere observation platform

    NASA Astrophysics Data System (ADS)

    Weiler, Markus; Blume, Theresa

    2016-04-01

    Most catchment based observations linking hydrometeorology, ecohydrology, soil hydrology and hydrogeology are typically not integrated with each other and lack a consistent and appropriate spatial-temporal resolution. Within the research network CAOS (Catchments As Organized Systems), we have initiated and developed a novel and integrated observation platform in several catchments in Luxembourg. In 20 nested catchments covering three distinct geologies the subscale processes at the bedrock-soil-vegetation-atmosphere interface are being monitored at 46 sensor cluster locations. Each sensor cluster is designed to observe a variety of different fluxes and state variables above and below ground, in the saturated and unsaturated zone. The numbers of sensors are chosen to capture the spatial variability as well the average dynamics. At each of these sensor clusters three soil moisture profiles with sensors at different depths, four soil temperature profiles as well as matric potential, air temperature, relative humidity, global radiation, rainfall/throughfall, sapflow and shallow groundwater and stream water levels are measured continuously. In addition, most sensors also measure temperature (water, soil, atmosphere) and electrical conductivity. This setup allows us to determine the local water and energy balance at each of these sites. The discharge gauging sites in the nested catchments are also equipped with automatic water samplers to monitor water quality and water stable isotopes continuously. Furthermore, water temperature and electrical conductivity observations are extended to over 120 locations distributed across the entire stream network to capture the energy exchange between the groundwater, stream water and atmosphere. The measurements at the sensor clusters are complemented by hydrometeorological observations (rain radar, network of distrometers and dense network of precipitation gauges) and linked with high resolution meteorological models. In this

  16. Use of GIS Technology in Surface Water Monitoring fro Targeted Policy Intervention in a Mountainous Catchment in Romania

    NASA Astrophysics Data System (ADS)

    Giali, Gabriela; Schneider, Petra

    2015-04-01

    USE OF GIS TECHNOLOGY IN SURFACE WATER MONITORING FOR TARGETED POLICY INTERVENTION IN A MOUNTAINOUS CATCHMENT IN ROMANIA The collection of information on surface water quality is a specific activity that takes place systematically and regularly at regional and national scale, and it is important for the assessment of the water quality as well as for water management policy-making. A data base information management using a Geographical Information System (GIS) forms an important aspect of environmental management, which provides the frame for processing and visualisation of water monitoring data and information as well as for the optimisation of monitoring concepts. This paper presents an architecture performed by a GIS which provides a grafic database and attributes the nesessary measurements of the water quality to different sections of the mountainous catchment of the Suceava river in the north of Romania. With this approach the location of the water sampling points can be optimised in terms of the selection and setting of the river sections. To facilitate the setting of the sampling locations in the various sections of water sampling in the river, the presented GIS system provides to the user different information layers with combined or isolated data according to the objectives. In the frame of the research were created 5 layers of information in the basin under study, underlying the determination of a new information layer, namely the "Hydrografic Network Graded to Hydrographic Sections". Practically, in the studied basin were established 8 sections for water sampling locations, and the water quality characterization was done by the consideration of 15 quality indicators. The GIS system presented in this research is a valuable, useful and adaptable to land use changes data base that can be exploited by any number of combinations, its capabilities justify it's role as "tool to support decision making." With this characteristics it supports the policy-making of

  17. Stakeholder discourse and water management in a catchment in northern Italy

    NASA Astrophysics Data System (ADS)

    Lupo Stanghellini, P. S.; Collentine, D.

    2007-06-01

    The Water Framework Directive (WFD; directive 2000/60/EC) was created to ensure the sustainable use of water resources in the European Union. A central guideline included throughout the directive is a call for the participation of stakeholders in the management of these resources. Involving stakeholders is an important step to ensure that catchment management plans take into consideration local experience in the development of these plans and the impact of the plans on local interests. This paper describes and analyses the results of a series of workshops to facilitate implementation of the WFD at a catchment level based on the stakeholder participation model, CATCH. To test the usefulness of the stakeholder participation model CATCH for water management in a catchment area, a sub-catchment in an alpine valley in the north-east of Italy, the Alta Valsugana in the Province of Trento, was chosen as the setting for a series of workshops. In this valley water is fundamental for activities associated with agriculture, domestic use, energy production, sports and recreation. In the recent past the valley has had serious problems related to water quality and quantity. Implementation of water management plans under the WFD may lead to conflicts within the catchment between different stakeholder interest groups. Including stakeholders in the development of management plans not only follows the guidelines of the WFD but also could result in a more locally adapted and acceptable plan for the catchment. A new stakeholder analysis methodology was developed and implemented in order to identify the relevant stakeholders of the area and then two sets of workshops involving the key stakeholders identified were conducted in Spring 2006. The CATCH meetings were a new experience for the participants, who had to deal with both the principles of the WFD in general and the participation requirement in particular. During the meetings, the CATCH model played a very important role in

  18. Hydrologic connectivity between landscapes and streams: Transferring reach- and plot-scale understanding to the catchment scale

    USGS Publications Warehouse

    Jencso, K.G.; McGlynn, B.L.; Gooseff, M.N.; Wondzell, S.M.; Bencala, K.E.; Marshall, L.A.

    2009-01-01

    The relationship between catchment structure and runoff characteristics is poorly understood. In steep headwater catchments with shallow soils the accumulation of hillslope area (upslope accumulated area (UAA)) is a hypothesized first-order control on the distribution of soil water and groundwater. Hillslope-riparian water table connectivity represents the linkage between the dominant catchment landscape elements (hillslopes and riparian zones) and the channel network. Hydrologic connectivity between hillslope-riparian-stream (HRS) landscape elements is heterogeneous in space and often temporally transient. We sought to test the relationship between UAA and the existence and longevity of HRS shallow groundwater connectivity. We quantified water table connectivity based on 84 recording wells distributed across 24 HRS transects within the Tenderfoot Creek Experimental Forest (U.S. Forest Service), northern Rocky Mountains, Montana. Correlations were observed between the longevity of HRS water table connectivity and the size of each transect's UAA (r2 = 0.91). We applied this relationship to the entire stream network to quantify landscape-scale connectivity through time and ascertain its relationship to catchment-scale runoff dynamics. We found that the shape of the estimated annual landscape connectivity duration curve was highly related to the catchment flow duration curve (r2 = 0.95). This research suggests internal catchment landscape structure (topography and topology) as a first-order control on runoff source area and whole catchment response characteristics. Copyright 2009 by the American Geophysical Union.

  19. Hydropedological insights when considering catchment classification

    NASA Astrophysics Data System (ADS)

    Bouma, J.; Droogers, P.; Sonneveld, M. P. W.; Ritsema, C. J.; Hunink, J. E.; Immerzeel, W. W.; Kauffman, S.

    2011-02-01

    Soil classification systems are analysed in relation to the functioning and characterisation of catchments. Soil classifications are useful to create systematic order in the overwhelming quantity of different soils in the world and to extrapolate data available for a given soil type to soils elsewhere with identical classifications. However, such classifications are based on permanent characteristics as formed by the soil forming factors over often very long periods of time and this does not necessarily match with characteristics and parameters needed for functional soil characterization focusing, for example, on catchment hydrology. Hydropedology has made contributions towards functional characterization of soils as is illustrated for recent hydrological catchment studies. However, much still needs to be learned about the physical behaviour of anisotropic, heterogeneous field soils with varying soil structures during the year and the suggestion is made to first focus on improving simulation of catchment hydrology, incorporating hydropedological expertise, before embarking on a classification effort which involves major input of time and involves the risk of distraction. In doing so, we advise to also define other characteristics for catchment performance than the traditionally measured discharge rates.

  20. Catchment coevolution: A useful framework for improving predictions of hydrological change?

    NASA Astrophysics Data System (ADS)

    Troch, Peter A.; Lahmers, Tim; Meira, Antonio; Mukherjee, Rajarshi; Pedersen, Jonas W.; Roy, Tirthankar; Valdés-Pineda, Rodrigo

    2015-07-01

    The notion that landscape features have coevolved over time is well known in the Earth sciences. Hydrologists have recently called for a more rigorous connection between emerging spatial patterns of landscape features and the hydrological response of catchments, and have termed this concept catchment coevolution. In this paper we review recent literature on this subject and attempt to synthesize what we have learned into a general framework that would improve predictions of hydrologic change. We first present empirical evidence of the interaction and feedback of landscape evolution and changes in hydrological response. From this review it is clear that the independent drivers of catchment coevolution are climate, geology, and tectonics. We identify common currency that allows comparing the levels of activity of these independent drivers, such that, at least conceptually, we can quantify the rate of evolution or aging. Knowing the hydrologic age of a catchment by itself is not very meaningful without linking age to hydrologic response. Two avenues of investigation have been used to understand the relationship between (differences in) age and hydrological response: (i) one that is based on relating present landscape features to runoff processes that are hypothesized to be responsible for the current fingerprints in the landscape; and (ii) one that takes advantage of an experimental design known as space-for-time substitution. Both methods have yielded significant insights in the hydrologic response of landscapes with different histories. If we want to make accurate predictions of hydrologic change, we will also need to be able to predict how the catchment will further coevolve in association with changes in the activity levels of the drivers (e.g., climate). There is ample evidence in the literature that suggests that whole-system prediction of catchment coevolution is, at least in principle, plausible. With this imperative we outline a research agenda that

  1. A methodology to determine pesticides pollution sources in water catchments: study case (Belgium).

    PubMed

    Limbourg, Q; Noel, S; Huyghebaert, B; Capette, L; Hallet, V

    2009-01-01

    In the Walloon Region (Belgium), a Committee of Investigation was created in 2007 to investigate and determine the potential pesticides pollution sources in drinkable water catchments. This Committee, constituted by a multidisciplinary team of experts i.e agronomists, soil scientists, phyto-chemists, hydrogeologists, is coordinated by the Walloon Agricultural Research Centre (CRA-W) and funded by the Société Publique de Gestion des Eaux (SPGE). The diagnosis method is inspired of the AQUAPLAINE method (Arvalis, France), and is composed of four steps: 1/preparing the diagnosis using existing data, 2/diagnosis using data bank completed by field observations, 3/meeting and discussion with the pesticide users, 4/final diagnosis and remediation proposal. In a rural district of Walloon Region, a water producer who possesses two catchments ("Les marroniers" (P1) and "Puits N2" (P2)) has problems with pesticides. The pollution started in 1998 with atrazine and bromacile detected in the two catchments. In 2004, 2,6-dichlorobenzamide, metabolite of dichlobenil, was also detected in the catchments. At present, all these pesticides are still found in the catchment P1 and only the 2,6 dichlorobenzamide is found in the other catchment. These active ingredients are not used in agriculture expect atrazine. Indeed, the main user of these products is the public sector. An investigation was realised to locate the main sites which are treated with these pesticides in this commune. The conclusion of this study is that the local authority used dichlobenil, bromacile and atrazine to weed the public areas. In more, the filling and the cleaning areas of sprayer, used for the treatment, are located near the catchments. PMID:20218526

  2. Identifying critical source areas for phosphorus loss in Ireland using field and catchment scale ranking schemes

    NASA Astrophysics Data System (ADS)

    Hughes, K. J.; Magette, W. L.; Kurz, I.

    2005-03-01

    Phosphorus (P) in agricultural runoff is a major pollutant in many of Ireland's surface waters. Identification of areas that are at a high risk for P loss to surface waters is a critical component of river basin management. Two P ranking schemes (PRS's) were developed for Ireland, based on multi-criteria analysis approaches proposed in both the US and Europe, to predict the relative likelihood of P loss at both the field and catchment scales. The Field PRS was evaluated by comparing predicted rankings of potential P loss and transport against measured edge-of-field Dissolved Reactive P (DRP) loss for three fields with varying soil P levels. Qualitatively, results indicated that the Field PRS rankings corresponded to the magnitudes of measured P loss for the field sites, as well as to a reasoned evaluation of the relative likelihood that the fields would lose P that would subsequently make its way to surface water. The Catchment PRS was evaluated on a total of 31 catchments and sub-catchments by comparing predicted rankings of potential P loss and transport against measured in-stream median Molybdate Reactive P (MRP). Rankings of the relative likelihood of P loss and transport predicted by the Catchment PRS were positively correlated with median in-stream MRP ( r=0.51, P<0.05). Although the data available for these evaluations were limited, especially at field scale, and further research may identify the opportunity for modifications, both field and catchment scale P ranking schemes demonstrated a potential for identifying critical P source areas within catchments dominated by grass-based agricultural production systems, such as those in Ireland.

  3. Scaling ET from different data sources gives insight in catchment processes

    NASA Astrophysics Data System (ADS)

    Vervoort, Willem; Henry, Joseph; Gharun, Mana; Adams, Mark

    2014-05-01

    Depending on the available funding and equipment, environmental data are often available at one scale, while predictions or forecasts are needed at a larger or smaller scale. The scientific literature is therefore full of comments and papers about scaling, upscaling and downscaling. Brought back to its basics, all scaling problems are essentially model prediction problems. Thus seeking a universal scaling law is unlikely to deliver results. Our interest has been in scaling evapotranspiration. A literature review revealed that most of the work in estimating evapotranspiration in Australia has occurred at short time scales at the local tree level, scaling to the stand or hillslope level. There has been limited work at scaling to larger scales, such as the catchment, although there has been work at the much larger continental scales (reference), scaling from a limited number of EC towers. However, from a hydrological prediction point of view, estimates of evapotranspiration at the catchment scale or distributed across the catchment scale are crucial to improve water balance estimates for water resource management. Here we compare several different approaches to scale local ET estimates to catchment scale ET and highlight how they all produce different results due to limitations with each of the methods. However, each of the scaling exercises reveals other aspects of the overall catchment system behaviour that cannot be identified at an individual scale. In this research we used collected field site in a model (WAVES) to predict local scale ET using different approaches and scaled this to catchment level ET, derived from the water balance and derived from the satellite MODIS ET estimates. The model was calibrated to sapflow measurements scaled to stand, introducing another opportunity for uncertainty. We discuss how at each of this scales lack of knowledge influences the estimates, but that the combined analysis reveals more about the temporal and spatial variation in

  4. Differentiating causes for erosion at the catchment scale: do soil conservation measures mitigate weather dynamics?

    NASA Astrophysics Data System (ADS)

    Barneveld, Robert; Greipsland, Inga

    2016-04-01

    The efficacy of most measures to control soil loss is well established at the field or plot scale. Less well documented are the changes in hydrological behaviour and sediment production at the scale of the (small) catchment. In Norway, incentives to reduce tillage have been in place for over decades. However, even long time (20 years) discharge monitoring of a series of small catchments does not show a clear effect of the application of conservation measures. This research hypothesizes that the effect of weather conditions for a 4.2 km2 catchment in southeastern Norway outweighs the effect of conservation measures in the time series on runoff and sediment load. To test this, it was assumed that trends and changes in soil loss E over time are the product of an agromic index C, precipitation P and rainfall erosivity R. The values of C were calculated based on extensive farm records, covering every tillage operation for every field in the catchment for the period of investigation. Runoff and sediment load records were used to parameterise and test different correlative models. In order to quantify the effect of topography on the degree to which conservations measures reduce soil loss at catchment level, a spatially distributed connectivity index was calculated and multiplied with C. Calculations were carried out for a 10 year period, in monthly time steps. The following statistical models proved the most promising to correlate sediment load to precipitation and agronomic practice. Et=a \\cdot Ptb \\cdot Pt-1c \\cdot Ctd Et=a \\cdot Rtb \\cdot Pt-1c \\cdot Ctd where Pt-1c, the precipition in the prior month, is a proxy indicator for antecedent moisture conditions. The results show that precipitation dynamics outweigh the effect of soil conservation measures for this typical agricultural catchment. It also shows that the inclusion of a hydrological connectivity index improves the quantification of the effect of soil conservation measures on the catchment scale.

  5. GLOBAL CHANGE RESEARCH NEWS #33: PUBLICATION OF RESEARCH AGENDA FROM UNITED STATES - CANADA SYMPOSIUM ON NORTH AMERICAN CLIMATE CHANGE AND WEATHER EXTREMES

    EPA Science Inventory

    A three-day workshop on climate variability and change and extreme weather events in North America was held in October 1999 in Atlanta, Georgia. The workshop was a bi-national effort conducted under the auspices of a United States - Canada agreement fostering cooperation on activ...

  6. Sources of sediment in catchments and its eutrophication potential

    NASA Astrophysics Data System (ADS)

    Krasa, Josef; Dostal, Tomas; Bauer, Miroslav; Janotova, Barbora; Rosendorf, Pavel

    2013-04-01

    reservoirs is an important source of data for balancing phosphorus sources but often misses the episodic erosion inputs. WATEM/SEDEM shows up to be reasonable tool for sediment transport and particulate phosphorus transport within large catchments, even though getting relevant high resolution input data is a limiting factor for assessment. The topography and land-use data are good enough for defining the spatial pattern of erosion and deposition, but for getting actual sediment transport volumes there are not enough data on precipitation, and stream hydrology. Acknowledgements Research is supported by the NAZV project No. QI102A265 "Assessment of soil erosion and phosphorus loads causing eutrophication of stagnant water bodies" and QI91C008 "Optimization of design of technical soil erosion control measures". References Dendy, F.E., and W.A. Champion. 1978. Sediment Deposition in U.S. Reservoirs. MP-1362. U.S. Dept. Agr., Agr. Res. Serv. Sharpley A. N.: Dependence of runoff phosphorus on extractable soil phosphorus. J. Environ. Qual., 24, (1995), p. 920-926. Van Rompaey A, Verstraeten G, Van Oost K, Govers G & Poesen J, 2001. Modeling mean annual sediment yield using a distributed approach. Earth Surface Processes and Landforms 26 (11), 1221-1236.

  7. Hydrological monitoring of experimental karst catchment Sutina - Karakašica

    NASA Astrophysics Data System (ADS)

    Bonacci, O.; Andrić, I.

    2012-04-01

    The Sutina - Karakašica is an ungauged karst catchment in southern part of Croatia with relative small area but with existing records of several events of flash flood that compromised the structures as bridge and roads along the stream. This poster gives an overview of the creation of the experimental catchment and establishment of the hydrological monitoring system which has for a goal a better understanding of runoff processes within the experimental karst area as well as flash flood occurrence analysis. The studied catchment is located in Dalmatia, southern part of Croatia, a region of Dinaric karst. Although it is very difficult to determine catchment borders in the karstic terrain, for the porpoises of the study the area of the catchment is estimated to 8 km2. The length of the stream flow up to the control cross section is 4.4 km. The highest point of the studied catchment area is on the 941 m a.s.l. and the lowest at the 300 m a.s.l. The geological settings of the catchment are characterized by the sedimentary rocks, mostly limestone and dolomites with discontinuities (cracks, and fractures) filled up with terra rossa and breccias. The presence of mudstone patches in the surface ensures the continuous surface flow of the studied stream. Some caves are also to be found in the catchment area. In the karst watersheds the occurrence of flash floods can be registered due to the exceptional meteorologic events during the year. The intensive rainfall in the short time period can trigger a flash flood that can induce overbank flow, immense changes in channel morphology and in sediment distribution. In order to produce a hydrological model that could predict the events of flash flood in the studied area, a continuous monitoring of meteorological and hydrological parameters in the catchment is established. The predictions of exceptional flooding events derived from a useful hydrological model based on the study site can be used further on to quantify the possible

  8. Before and After Integrated Catchment Management in a Headwater Catchment: Changes in Water Quality

    NASA Astrophysics Data System (ADS)

    Hughes, Andrew O.; Quinn, John M.

    2014-12-01

    Few studies have comprehensively measured the effect on water quality of catchment rehabilitation measures in comparison with baseline conditions. Here we have analyzed water clarity and nutrient concentrations and loads for a 13-year period in a headwater catchment within the western Waikato region, New Zealand. For the first 6 years, the entire catchment was used for hill-country cattle and sheep grazing. An integrated catchment management plan was implemented whereby cattle were excluded from riparian areas, the most degraded land was planted in Pinus radiata, channel banks were planted with poplar trees and the beef cattle enterprise was modified. The removal of cattle from riparian areas without additional riparian planting had a positive and rapid effect on stream water clarity. In contrast, the water clarity decreased in those sub-catchments where livestock was excluded but riparian areas were planted with trees and shrubs. We attribute the decrease in water clarity to a reduction in groundcover vegetation that armors stream banks against preparatory erosion processes. Increases in concentrations of forms of P and N were recorded. These increases were attributed to: (i) the reduction of instream nutrient uptake by macrophytes and periphyton due to increased riparian shading; (ii) uncontrolled growth of a nitrogen fixing weed (gorse) in some parts of the catchment, and (iii) the reduction in the nutrient attenuation capacity of seepage wetlands due to the decrease in their areal coverage in response to afforestation. Our findings highlight the complex nature of the water quality response to catchment rehabilitation measures.

  9. Investigating the potential to reduce flood risk through catchment-based land management techniques and interventions in the River Roe catchment, Cumbria,UK

    NASA Astrophysics Data System (ADS)

    Pearson, Callum; Reaney, Sim; Bracken, Louise; Butler, Lucy

    2015-04-01

    Throughout the United Kingdom flood risk is a growing problem and a significant proportion of the population are at risk from flooding throughout the country. Across England and Wales over 5 million people are believed to be at risk from fluvial, pluvial or coastal flooding (DEFRA, 2013). Increasingly communities that have not dealt with flooding before have recently experienced significant flood events. The communities of Stockdalewath and Highbridge in the Roe catchment, a tributary of the River Eden in Cumbria, UK, are an excellent example. The River Roe has a normal flow of less than 5m3 sec-1 occurring 97 percent of the time however there have been two flash floods of 98.8m3 sec-1 in January 2005 and 86.9m3 sec-1 in May 2013. These two flash flood events resulted in the inundation of numerous properties within the catchment with the 2013 event prompting the creation of the Roe Catchment Community Water Management Group which aims are to deliver a sustainable approach to managing the flood risk. Due to the distributed rural population the community fails the cost-benefit analysis for a centrally funded flood risk mitigation scheme. Therefore the at-risk community within the Roe catchment have to look for cost-effective, sustainable techniques and interventions to reduce the potential negative impacts of future events; this has resulted in a focus on natural flood risk management. This research investigates the potential to reduce flood risk through natural catchment-based land management techniques and interventions within the Roe catchment; providing a scientific base from with further action can be enacted. These interventions include changes to land management and land use, such as soil aeration and targeted afforestation, the creation of runoff attenuation features and the construction of in channel features, such as debris dams. Natural flood management (NFM) application has been proven to be effective when reducing flood risk in smaller catchments and the

  10. Catchment scale multi-objective flood management

    NASA Astrophysics Data System (ADS)

    Rose, Steve; Worrall, Peter; Rosolova, Zdenka; Hammond, Gene

    2010-05-01

    Rural land management is known to affect both the generation and propagation of flooding at the local scale, but there is still a general lack of good evidence that this impact is still significant at the larger catchment scale given the complexity of physical interactions and climatic variability taking place at this level. The National Trust, in partnership with the Environment Agency, are managing an innovative project on the Holnicote Estate in south west England to demonstrate the benefits of using good rural land management practices to reduce flood risk at the both the catchment and sub-catchment scales. The Holnicote Estate is owned by the National Trust and comprises about 5,000 hectares of land, from the uplands of Exmoor to the sea, incorporating most of the catchments of the river Horner and Aller Water. There are nearly 100 houses across three villages that are at risk from flooding which could potentially benefit from changes in land management practices in the surrounding catchment providing a more sustainable flood attenuation function. In addition to the contribution being made to flood risk management there are a range of other ecosystems services that will be enhanced through these targeted land management changes. Alterations in land management will create new opportunities for wildlife and habitats and help to improve the local surface water quality. Such improvements will not only create additional wildlife resources locally but also serve the landscape response to climate change effects by creating and enhancing wildlife networks within the region. Land management changes will also restore and sustain landscape heritage resources and provide opportunities for amenity, recreation and tourism. The project delivery team is working with the National Trust from source to sea across the entire Holnicote Estate, to identify and subsequently implement suitable land management techniques to manage local flood risk within the catchments. These

  11. Validation of Pacific Northwest hydrologic landscapes at the catchment scale

    EPA Science Inventory

    The interaction between the physical properties of a catchment (form) and climatic forcing of precipitation and energy control how water is partitioned, stored, and conveyed through a catchment (function). Hydrologic Landscapes (HLs) were previously developed across Oregon and de...

  12. Use of color maps and wavelet coherence to discern seasonal and interannual climate influences on streamflow variability in northern catchments

    NASA Astrophysics Data System (ADS)

    Carey, Sean K.; Tetzlaff, Doerthe; Buttle, Jim; Laudon, Hjalmar; McDonnell, Jeff; McGuire, Kevin; Seibert, Jan; Soulsby, Chris; Shanley, Jamie

    2013-10-01

    The higher midlatitudes of the northern hemisphere are particularly sensitive to change due to the important role the 0°C isotherm plays in the phase of precipitation and intermediate storage as snow. An international intercatchment comparison program called North-Watch seeks to improve our understanding of the sensitivity of northern catchments to change by examining their hydrological and biogeochemical variability and response. Here eight North-Watch catchments located in Sweden (Krycklan), Scotland (Girnock and Strontian), the United States (Sleepers River, Hubbard Brook, and HJ Andrews), and Canada (Dorset and Wolf Creek) with 10 continuous years of daily precipitation and runoff data were selected to assess daily to seasonal coupling of precipitation (P) and runoff (Q) using wavelet coherency, and to explore the patterns and scales of variability in streamflow using color maps. Wavelet coherency revealed that P and Q were decoupled in catchments with cold winters, yet were strongly coupled during and immediately following the spring snowmelt freshet. In all catchments, coupling at shorter time scales occurred during wet periods when the catchment was responsive and storage deficits were small. At longer time scales, coupling reflected coherence between seasonal cycles, being enhanced at sites with enhanced seasonality in P. Color maps were applied as an alternative method to identify patterns and scales of flow variability. Seasonal versus transient flow variability was identified along with the persistence of that variability on influencing the flow regime. While exploratory in nature, this intercomparison exercise highlights the importance of climate and the 0°C isotherm on the functioning of northern catchments.

  13. A satellite-based approach for land cover/use changes in Acheron River catchment (Greece)

    NASA Astrophysics Data System (ADS)

    Kostara, Aikaterini; Retalis, Adrianos; Papastergiadou, Eva

    2013-08-01

    Mediterranean landscape has undergone many significant changes during last decades. Especially river catchments are among the threatened landscapes in the world, mainly due to human activities and land cover changes. This description demonstrates the case of Acheron River catchment, which is a typical of many Mediterranean catchments cases. Human activities, through its impact on land cover and use, affect this ecological succession at various degrees in the whole catchment area. The proposed analysis focuses on the use of the normalized difference vegetation index (NDVI), which can provide important information in terms of vegetation productivity and status, which represents one of the most sensitive landscape components to environmental degradation. Emphasis is given to the spatiotemporal dynamic patterns of land cover/use changes for the period 1984 - 2011 with Landsat-TM imagery. Land use disturbances in the catchment's area decreased habitat integrity, with maximum habitat integrity recorded in the upper river reaches, known as the Straits of Acheron, through a narrow and magnificent gorge created by mountains. Human interventions have changed the river beds, increased landscape fragmentation, and led to the degradation and loss of wetland habitats. Additionally the current research could be a valuable tool for the river managers to develop area-specific policies that minimize human influences.

  14. Identification of internal flow dynamics in two experimental catchments

    USGS Publications Warehouse

    Hansen, D.P.; Jakeman, A.J.; Kendall, C.; Weizu, G.

    1997-01-01

    Identification of the internal flow dynamics in catchments is difficult because of the lack of information in precipitation -stream discharge time series alone. Two experimental catchments, Hydrohill and Nandadish, near Nanjing in China, have been set up to monitor internal flows reaching the catchment stream at various depths, from the surface runoff to the bedrock. With analysis of the precipitation against these internal discharges, it is possible to quantify the time constants and volumes associated with various flowpaths in both catchments.

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    Over the past decade many European catchments have experienced an unusually high number of flood events. A large number of these events are the result of intense rainfall in small headwater catchments which are dominated by surface runoff generation, resulting in flash flooding of local communities. Soil erosion and related water quality issues, among others, are typically associated with such rapid runoff generation. The hazard of flooding is increasing owing to impacts of changing climatic patterns (including more intense summer storms), intensification of agriculture within rural catchments and continued pressure to build on floodplains. Concurrently, the cost of constructing and maintaining traditional flood defences in small communities outweigh the potential benefits. Hence, there is a growing interest in more cost effective natural approaches that also have multipurpose benefits in terms of sediment, water quality, and habitat creation. Many catchments in Europe are intensively farmed and there is great potential for agriculture to be part of the solution to flood risk management. Natural flood management (NFM) is the alteration, restoration or use of landscape features with the aim of reducing flood risk by slowing down, storing (and filtering) rapid surface runoff. NFM includes measures such as temporarily storing water in ponds/wetlands, increasing soil infiltration, planting trees on floodplains and within catchments, re-meandering and wood placements in streams/ditches. In this presentation we highlight case studies from densely instrumented research sites across the UK (which could be typical of many European catchments) where NFM measures have been installed in small scale flashy catchments. The presentation will give an overview of the function of these measures in these catchments and how other multiple benefits are being accrued. Study catchments include the headwater catchments of the Bowmont (3 to 8 km2) and Belford Burn (6 km2) catchments. These

  16. Assessing and Synthesizing the Last Decade of Research on the Major Pools and Fluxes of the Carbon Cycle in the US and North America: An Interagency Governmental Perspective

    NASA Astrophysics Data System (ADS)

    Cavallaro, N.; Shrestha, G.; Stover, D. B.; Zhu, Z.; Ombres, E. H.; Deangelo, B.

    2015-12-01

    The 2nd State of the Carbon Cycle Report (SOCCR-2) is focused on US and North American carbon stocks and fluxes in managed and unmanaged systems, including relevant carbon management science perspectives and tools for supporting and informing decisions. SOCCR-2 is inspired by the US Carbon Cycle Science Plan (2011) which emphasizes global scale research on long-lived, carbon-based greenhouse gases, carbon dioxide and methane, and the major pools and fluxes of the global carbon cycle. Accordingly, the questions framing the Plan inform this report's topical roadmap, with a focus on US and North America in the global context: 1) How have natural processes and human actions affected the global carbon cycle on land, in the atmosphere, in the oceans and in the ecosystem interfaces (e.g. coastal, wetlands, urban-rural)? 2) How have socio-economic trends affected the levels of the primary carbon-containing gases, carbon dioxide and methane, in the atmosphere? 3) How have species, ecosystems, natural resources and human systems been impacted by increasing greenhouse gas concentrations, the associated changes in climate, and by carbon management decisions and practices? To address these aspects, SOCCR-2 will encompass the following broad assessment framework: 1) Carbon Cycle at Scales (Global Perspective, North American Perspective, US Perspective, Regional Perspective); 2) Role of carbon in systems (Soils; Water, Oceans, Vegetation; Terrestrial-aquatic Interfaces); 3) Interactions/Disturbance/Impacts from/on the carbon cycle. 4) Carbon Management Science Perspective and Decision Support (measurements, observations and monitoring for research and policy relevant decision-support etc.). In this presentation, the Carbon Cycle Interagency Working Group and the U.S. Global Change Research Program's U.S. Carbon Cycle Science Program Office will highlight the scientific context, strategy, structure, team and production process of the report, which is part of the USGCRP's Sustained

  17. Storage selection functions: A coherent framework for quantifying how catchments store and release water and solutes

    NASA Astrophysics Data System (ADS)

    Rinaldo, Andrea; Benettin, Paolo; Harman, Ciaran J.; Hrachowitz, Markus; McGuire, Kevin J.; van der Velde, Ype; Bertuzzo, Enrico; Botter, Gianluca

    2015-06-01

    We discuss a recent theoretical approach combining catchment-scale flow and transport processes into a unified framework. The approach is designed to characterize the hydrochemistry of hydrologic systems and to meet the challenges posed by empirical evidence. StorAge Selection functions (SAS) are defined to represent the way catchment storage supplies the outflows with water of different ages, thus regulating the chemical composition of out-fluxes. Biogeochemical processes are also reflected in the evolving residence time distribution and thus in age-selection. Here we make the case for the routine use of SAS functions and look forward to areas where further research is needed.

  18. Using protection motivation theory and formative research to guide an injury prevention intervention: increasing adherence to the North American Guidelines for Children's Agricultural Tasks.

    PubMed

    Ashida, Sato; Heaney, Catherine A; Kmet, Jennifer M; Wilkins, J R

    2011-05-01

    The North American Guidelines for Children's Agricultural Tasks (NAGCAT) were developed to reduce childhood agricultural injuries by assisting adults in assigning appropriate chores and providing needed supervision and training. To develop an effective intervention to increase adherence to NAGCAT among farm parents, formative research (focus groups and pilot-testing) was conducted. Protection motivation theory (PMT) was used to guide this research and inform intervention development. Focus group results suggested how PMT constructs might be addressed to increase adherence. A home visit intervention, using a standardized presentation in POWERPoint™, was developed to (a) introduce NAGCAT, (b) increase motivation to use NAGCAT and enhance safe work behaviors, and (c) ultimately reduce agricultural work-related injuries among youth. Process evaluation data suggests that the intervention was well received by farm parents. Conducting theory-guided formative research identified motivational barriers and strategies for overcoming these barriers that might not have been otherwise apparent. PMID:21518923

  19. North Carolina

    Atmospheric Science Data Center

    2014-05-15

    ... (Terra orbit 4344) captures the intricate system of barrier islands, wetlands, and estuaries comprising the coastal environments of North ... formats available at JPL October 11, 2000 - Barrier islands, wetlands, and estuaries of coastal North Carolina and ...

  20. Modeling daily streamflow at ungauged catchments: What information is necessary?

    NASA Astrophysics Data System (ADS)

    Patil, S.; Stieglitz, M.

    2011-12-01

    Streamflow modeling at ungauged catchments involves transfer of information (viz., model structure and parameters) from gauged to ungauged catchments that are judged to be hydrologically similar. In this study, we focus on identifying: (1) what constitutes the critical information that needs to be transferred among hydrologically similar catchments to achieve good predictability using models at ungauged sites, and (2) which is the best approach for transferring this information from gauged to ungauged catchments. We develop a simple hydrologic model with minimal calibration requirement and implement it over 756 catchments located across the continental United States. The model computes water balance at a daily time-step and conceptualizes subsurface runoff through a storage-dependent exponential decline in saturated hydraulic conductivity. Snow accumulation and melt are modeled using the thermal degree-day concept. The calibrated model performs better in humid runoff-dominated regions than in the drier evapotranspiration-dominated regions. Results show that within a region, transfer of hydrograph recession information alone is sufficient for reliable streamflow predictions at ungauged catchments. Information transfer from spatially proximate gauged catchments provides better streamflow predictability at ungauged catchments than transfer from catchments identified as physically similar. When considering spatially proximate catchments, information transfer from multiple donor catchments is preferable to transfer from a single donor catchment.

  1. Groundwater Contributions to Intermittent Streamflow in a Headwater Catchment: How do Geoclimatic Controls Influence Downstream Water Quality?

    NASA Astrophysics Data System (ADS)

    Smull, E. M.; Gooseff, M. N.; Singha, K.

    2014-12-01

    Hydrologic connectivity of headwater catchments affects surface water yield and quality of downstream drinking water supplies. Lower Gordon Gulch, a 2.75 km2 catchment, is part of the Boulder Creek watershed - the primary drinking water supply for the city of Boulder, Colorado. We hypothesize that the geologic and climatic environment within the catchment controls the magnitude, timing, and duration of hydrologic connection between the landscape and the stream, and thus the distribution of major ions to the surface water. Specifically, bedrock patterns, vegetation type and density, and snowpack dynamics influence how precipitation inputs move from the hillslopes to the catchment outlet. Preliminary results suggest that north-facing hillslopes with steeper slopes, deeper weathering of bedrock, denser vegetation stands, and a seasonal snowpack, provide consistently greater groundwater inputs to the stream compared to the south-facing hillslopes. We believe that this is in part due to subsurface bedrock patterns forcing a dominate cross-valley gradient. Through an extensive observation network of hillslope wells, periodic stream water balance measurements, and synoptic chemistry samples, we plan to continue our assessment of the spatio-temporal connectivity dynamics throughout the seasonal dry down (late summer through winter), during which streamflow can be intermittent. Results will help to guide landuse practices of upland catchments with respect to their role in Boulder's drinking water supply.

  2. Identification of weathered structures and aquifers from resistivity observations in the Strengbach catchment (Vosges, France).

    NASA Astrophysics Data System (ADS)

    Gance, Julien; Sailhac, Pascal; Malet, Jean-Philippe; Viville, Daniel; Pierret, Marie-Claire

    2015-04-01

    In low mountain regions, natural water resources used for agriculture or drinking water generally come from natural sources. Management of these water resources is complex for some catchments where most of the water flows is exfiltrating from bedrock aquifers characterized by important spatial heterogeneity and different connectivity levels in space and time. The Strengbach catchment (Vosges, North East France) is a hydro-geochemical observatory monitored for more than 25 years. The numerous geochemical studies have highlighted the existence of different lithological and structural units in the catchment constituted by different weathered granitic aquifers. Their spatial extension has been determined through the measurement of the soil electrical resistivity using 20 Electrical Resistivity Tomography (ERT) profiles. The profiles have been inverted separately with the BERT software in 2D and compared to 2.5 D inversions, where the inversion accounts for the profile crossings. The comparison between 2D and 2.5D inversion results allows validating the 2-D assumption. The 20 profiles are distributed over the complete catchment and cover more densely the water source area of the Strengbach stream. The shallow resistivities (5-10 m) measured highlight several weathered zones possibly characterized by different porosity. A combined analysis with soil water conductivity measurements in boreholes allows proposing a map of the spatial extension of these units. The resistivity data are also used to assess the depth of the main reservoir at the scale of the catchment. The hypothesis of the existence of a deeper reservoir is brought out by Audio-Magneto Telluric (AMT) and Very Low Frequency (VLF) measurements.

  3. Morphometric properties of the trans-Himalayan river catchments: Clues towards a relative chronology of orogen-wide drainage integration

    NASA Astrophysics Data System (ADS)

    Ghosh, Parthasarathi; Sinha, Sayan; Misra, Arindam

    2015-03-01

    The geomorphological evolution of the Himalayan mountain belt both in terms of crustal deformation and concomitant erosion by surface processes has been suggested to have a profound influence on a number of earth system processes and has been extensively researched through a number of different techniques. The huge catchments of the trans-Himalayan rivers are the product of long-term fluvial erosion of the landscape. This work attempts to understand their evolution through a study of drainage network, morphology, and internal organization of the smaller watersheds nested within each catchment. Using morphometric techniques applied to an orogen-wide digital elevation data grid, we characterized the drainage network structure and catchment of all the 18 trans-Himalayan rivers situated between the exits of the Indus and Brahmaputra rivers and constructed rectangular approximations of the catchment geometries. With the help of catchment dimensions measured transverse and parallel to the strike of the orogen, and by analyzing the dimension and spatial dispositions of the rectangular approximations, we demonstrate that the trans-Himalayan catchment shapes cannot be explained only as a product of the headward enlargement of drainage networks on a topographic slope, or orogenic taper. Within individual catchments we identified the existence of drainage components (watersheds) that are organized in a systematic manner with respect to the first-order physiographic features of the Himalayas, formed at different periods of geological time. Each of them shows distinct morphometric characteristics that are indicative of differences in processes and / or time scale involved in their formation. The hypsometric properties of the watersheds occupying the upper part of the catchments suggest that they are the remnants of pre-orogenic drainage that became confined to the leeward side of the Himalayas before the advent of monsoon circulation. The shape and organization of the

  4. Global investigation of vegetation impact on mean annual catchment evapotranspiration

    NASA Astrophysics Data System (ADS)

    Peel, Murray C.; McMahon, Thomas A.; Finlayson, Brian L.

    2010-05-01

    Historically, relationships between catchment vegetation type, evapotranspiration and runoff have been assessed primarily through paired catchment studies. The literature contains results from over 200 of these studies from around the world but two factors limit the applicability of the results to the wider domain. Firstly, catchment areas are generally small (<10 km2). Secondly, the range of climate types is narrow, with temperate (Köppen C) and cold (Köppen D) climate types in the majority. Here we present results from a global assessment of the impact of vegetation type on mean annual catchment evapotranspiration for a large, spatially and climatically diverse dataset of 699 catchments. This assessment is based on analysis of areal precipitation, temperature, runoff, and land cover information from each catchment, which differs from the paired catchment methodology where streamflow responses to a controlled land cover change are assessed. When catchments are grouped by vegetation type, any evidence of differing vegetation impact on actual evapotranspiration will be observed through differences in mean annual actual evapotranspiration, defined as precipitation minus runoff. Stratifying catchments by climate type was observed to be important when assessing the vegetation impact on evapotranspiration. Tropical and temperate forested catchments had significantly higher median evapotranspiration (~170mm and ~130mm, respectively) than non-forested catchments. Cold forested catchments unexpectedly had significantly lower median evapotranspiration (~90mm) than non-forested catchments. No significant difference in median evapotranspiration was found between temperate evergreen and deciduous forested catchments, though sample sizes were small. Temperate evergreen needleleaf forested catchments had significantly higher median evapotranspiration than evergreen broadleaf forested catchments, though again sample sizes were small. The significant difference in median

  5. The assessment of developmental status using the Ages and Stages questionnaire-3 in nutritional research in north Indian young children

    PubMed Central

    2013-01-01

    Objective and background For large epidemiological studies in low and middle-income countries, inexpensive and easily administered developmental assessment tools are called for. This report evaluates the feasibility of the assessment tool Ages and Stages Questionnaire 3.edition (ASQ-3) “home procedure” in a field trial in 422 North Indian young children. Methods ASQ-3 was translated and adjusted for a North Indian Hindi setting. Three examiners were trained by a clinical psychologist to perform the assessments. During the main study, ten % of the assessments were done by two examiners to estimate inter-observer agreement. During all sessions, the examiners recorded whether the scoring was based on observation of the skill during the session, or on caregiver’s report of the child’s skill. Intra class correlation coefficient was calculated to estimate the agreement between the raters and between the raters and a gold standard. Pearson product moment correlation coefficient and standardized alphas were calculated to measure internal consistency. Principal findings Inter-observer agreement was strong both during training exercises and during the main study. In the Motor subscales and the Problem Solving subscale most items could be observed during the session. The standardized alphas for the total ASQ-3 scale across all ages were strong, while the alpha values for the different subscales and age levels varied. The correlations between the total score and the subscale scores were consistently strong, while the correlations between subscale scores were moderate. Conclusions/significance We found that the translated and adjusted ASQ-3 “home procedure” was a feasible procedure for the collection of reliable data on the developmental status in infants and young children. Examiners were effectively trained over a short period of time, and the total ASQ scores showed adequate variability. However, further adjustments are needed to obtain satisfying alpha values in

  6. Extending a rainfall-runoff model for lowland catchments from lumped to semi-distributed

    NASA Astrophysics Data System (ADS)

    Brauer, Claudia; Torfs, Paul; Teuling, Ryan; Uijlenhoet, Remko

    2016-04-01

    The Wageningen Lowland Runoff Simulator (WALRUS) is a parametric rainfall-runoff model for catchments with shallow groundwater (Brauer et al., 2014ab). WALRUS was developed using data and experience from two Dutch experimental catchments: the Hupsel Brook catchment (6.5 km2) and the Cabauw polder (0.5 km2). We identified key processes for runoff generation in lowland catchments, notably (1) groundwater-unsaturated zone coupling, (2) wetness-dependent flow routes, (3) groundwater-surface water feedbacks and (4) seepage and surface water supply, and accounted for these in the model structure. Up to now, WALRUS has been used in a lumped manner. However, water managers and researchers have expressed an interest in a semi-distributed version for application to larger catchments with varying forcing and catchment characteristics and to investigate the effect of groundwater flow within the catchment on modelled variables (e.g. groundwater depth). We combined WALRUS and a model for 2-dimensional groundwater flow into a simple modelling framework. WALRUS was already designed to cope with groundwater flow into or out of the model domain, because seepage and lateral groundwater flow are common in lowlands. In the semi-distributed version, we used this feature to couple different WALRUS elements (grid cells or subcatchments) to each other. Groundwater flow was computed using a digital elevation model, groundwater depths computed by WALRUS, soil transmissivity data and Darcy's law. Finally, we implemented a surface routing model including backwater effects, which are relevant in areas with little relief. With respect to the lumped version, the semi-distributed requires more data. Therefore, we investigated the added value of different data sources (forcing, elevation, soil, surface water) separately. We will present the rationale behind the semi-distributed model and show how the model structure compares to observations and and simulations without lateral transport. C.C. Brauer

  7. Using long time series of agricultural-derived nitrates for estimating catchment transit times

    NASA Astrophysics Data System (ADS)

    Fovet, O.; Ruiz, L.; Faucheux, M.; Molénat, J.; Sekhar, M.; Vertès, F.; Aquilina, L.; Gascuel-Odoux, C.; Durand, P.

    2015-03-01

    The estimation of water and solute transit times in catchments is crucial for predicting the response of hydrosystems to external forcings (climatic or anthropogenic). The hydrogeochemical signatures of tracers (either natural or anthropogenic) in streams have been widely used to estimate transit times in catchments as they integrate the various processes at stake. However, most of these tracers are well suited for catchments with mean transit times lower than about 4-5 years. Since the second half of the 20th century, the intensification of agriculture led to a general increase of the nitrogen load in rivers. As nitrate is mainly transported by groundwater in agricultural catchments, this signal can be used to estimate transit times greater than several years, even if nitrate is not a conservative tracer. Conceptual hydrological models can be used to estimate catchment transit times provided their consistency is demonstrated, based on their ability to simulate the stream chemical signatures at various time scales and catchment internal processes such as N storage in groundwater. The objective of this study was to assess if a conceptual lumped model was able to simulate the observed patterns of nitrogen concentration, at various time scales, from seasonal to pluriannual and thus if it was relevant to estimate the nitrogen transit times in headwater catchments. A conceptual lumped model, representing shallow groundwater flow as two parallel linear stores with double porosity, and riparian processes by a constant nitrogen removal function, was applied on two paired agricultural catchments which belong to the Research Observatory ORE AgrHys. The Global Likelihood Uncertainty Estimation (GLUE) approach was used to estimate parameter values and uncertainties. The model performance was assessed on (i) its ability to simulate the contrasted patterns of stream flow and stream nitrate concentrations at seasonal and inter-annual time scales, (ii) its ability to simulate the

  8. Investigating catchment-scale hysteretic behaviour of nutrients at annual and individual storm time-resolutions.

    NASA Astrophysics Data System (ADS)

    Lloyd, Charlotte; Freer, Jim; Johnes, Penny; Collins, Adrian

    2013-04-01

    The European Water Framework Directive (WFD) requires that all water bodies should be maintained at, or raised to, good ecological status, driven by improved integrated catchment management. Therefore, it is necessary to implement cost-effective mitigation strategies to reduce pollution from nutrients and improve overall water quality. If successful mitigation strategies are to be designed then it is imperative that catchment scale responses to environmental and anthropogenic changes are better understood. Against this background, this presentation investigates changes in hysteretic behaviours of nutrients in response to different environmental drivers using high resolution monitoring techniques. Observations of hysteretic behaviour can provide insights into the dominant flow pathways of pollutants. Therefore, monitoring changes in nutrient hysteresis can provide a useful tool for detecting regime differences or changes within and between catchments. In the UK, the Demonstration Test Catchment (DTC) project has been set up to monitor evidence for improving water quality problems arising specifically from diffuse pollution from agriculture using targeted mitigation experiments and high resolution monitoring. This research platform provides an opportunity to compare storm-driven nutrient behaviour between catchments which have differing geologies, as well as how these behaviours evolve on a seasonal and annual basis. The monitoring to date has included a period of drought, directly followed by extreme wet conditions in the UK and therefore offers opportunities to assess the effect of differences in antecedent conditions on monitored nutrient response to rainfall events. The study compares the hysteretic behaviour of nutrients, including nitrogen and phosphorus species as well as sediment from a number of storm events of varying magnitudes throughout the 2011-2012 monitoring period in the Hampshire Avon catchment as part of the DTC programme. The investigation focuses

  9. Model development based on a landscape oriented catchment unit concept

    NASA Astrophysics Data System (ADS)

    Cárdenas Gaudry, María.; Gutknecht, Dieter

    2010-05-01

    regional hydrological modelling using PRMS/MMS in the drainage basin of the river Bröl, Germany. Hydrological Processes 9, 424-436. Merz, R., Blöschl, G. (2009a): process controls on the statistical flood moments - a data based analysis. Hydrological Processes 23, 675-696. Merz, R., Blöschl, G. (2009b): A regional analysis of event runoff coefficients with respect to climate and catchment characteristics in Austria. Water Resources Research, Vol. 45, W01404, doi:10.1029/2008WR007163, 2009. Reszler, C. Komma, J., Blöschl, G., Gutknecht, D. (2008): Dominante Prozesse und Ereignistypen zur Plausibilisierung flächendetaillierter Niederschlag-Abflussmodelle. Hydrologie und Wasserbewirtschaftung 52, 120-131 Samuel, J.M., Sivapalan, M., Struthers, I. (2008): Diagnostic analysis of water balance variability: A comparative modeling study of catchments in Perth, Newcastle, and Darwin, Australia. Water Resources Research, Vol. 44, W06403, doi.10.1029/2007WR006694, 2008. Schmocker_Fackel, P., Scherrer, S. (2007): Identifying runoff processes on the plot and catchment scale. Hydrol. Earth Syst. Sci. 11, 891-906

  10. DOC quantity and quality in northeastern USA catchments

    NASA Astrophysics Data System (ADS)

    Shanley, J. B.; Sebestyen, S. D.; Aiken, G.; Pellerin, B. A.

    2011-12-01

    At the Sleepers River Research Watershed in Vermont we have studied interactions of dissolved organic carbon (DOC) cycling and hydrological processes for nearly 20 years to determine how and when DOC is transported through the landscape. Stream DOC concentration in this cool temperate forested catchment varies from ~1 to ~15 mg L-1 and is transport-limited; concentrations increase with increasing flow, even under the wettest conditions, suggesting shifting but non-depletable sources. Specific UV absorbance (SUVA) also increases consistently with flow. Source strength does vary seasonally, however, evidenced by higher DOC for a given flow during autumn leaf fall relative to spring snowmelt. Recent high-frequency optical sensor measurements have revealed fine-scale structure in the temporal DOC pattern not possible from discrete sampling. We observe a consistent counterclockwise hysteresis and diurnal cycles with seasonally variable amplitude. In this presentation we infer DOC sources and processes through analysis of antecedent moisture conditions and concurrent variations in nitrate, dissolved organic nitrogen, and SUVA. With sensors and sampling in place at several other research catchments, we are investigating the similarity of patterns across the northeastern USA.

  11. Establishment of a hydrological monitoring network in a tropical African catchment: An integrated participatory approach

    NASA Astrophysics Data System (ADS)

    Gomani, M. C.; Dietrich, O.; Lischeid, G.; Mahoo, H.; Mahay, F.; Mbilinyi, B.; Sarmett, J.

    Sound decision making for water resources management has to be based on good knowledge of the dominant hydrological processes of a catchment. This information can only be obtained through establishing suitable hydrological monitoring networks. Research catchments are typically established without involving the key stakeholders, which results in instruments being installed at inappropriate places as well as at high risk of theft and vandalism. This paper presents an integrated participatory approach for establishing a hydrological monitoring network. We propose a framework with six steps beginning with (i) inception of idea; (ii) stakeholder identification; (iii) defining the scope of the network; (iv) installation; (v) monitoring; and (vi) feedback mechanism integrated within the participatory framework. The approach is illustrated using an example of the Ngerengere catchment in Tanzania. In applying the approach, the concept of establishing the Ngerengere catchment monitoring network was initiated in 2008 within the Resilient Agro-landscapes to Climate Change in Tanzania (ReACCT) research program. The main stakeholders included: local communities; Sokoine University of Agriculture; Wami Ruvu Basin Water Office and the ReACCT Research team. The scope of the network was based on expert experience in similar projects and lessons learnt from literature review of similar projects from elsewhere integrated with local expert knowledge. The installations involved reconnaissance surveys, detailed surveys, and expert consultations to identify best sites. First, a Digital Elevation Model, land use, and soil maps were used to identify potential monitoring sites. Local and expert knowledge was collected on flow regimes, indicators of shallow groundwater plant species, precipitation pattern, vegetation, and soil types. This information was integrated and used to select sites for installation of an automatic weather station, automatic rain gauges, river flow gauging stations

  12. Modeling the water balance of a small Pinus radiata catchment.

    PubMed

    Whitehead, D.; Kelliher, F. M.

    1991-01-01

    An hourly biophysical model was used to calculate the water balance over a period of one year for an 8.7-ha catchment with a closed-canopy, 13-year-old Pinus radiata D. Don forest in the central North Island, New Zealand. Components of the model are transpiration from the dry tree canopy, evaporation from the partially wet tree canopy and stems, evaporation from the understory and soil, and drainage from a single-layer root zone. The model requires input of hourly weather data (net radiation, air and wet bulb temperatures, windspeed, and rainfall), tree stand characteristics (average height, tree number, leaf area index), physical characteristics of the site (root zone depth, relationship between root zone matric potential and volumetric water content, the relationship between the rate of drainage from the root zone and volumetric water content, and the area of open-stream channels). A submodel of the response of stomatal conductance to air saturation deficit and root zone matric potential is also required. Tree transpiration (704 mm year(-1) or 50% of annual rainfall) was a dominant component of the catchment water balance. Estimated evaporation from the wet tree canopy was 203 mm year(-1) (15%). Evaporation from the understory was much less, amounting to 94 mm year(-1) (7%) and an increase in water storage for the 3.5 m root zone depth was estimated to be 53 mm year(-1) (4%). Estimated daily rates of drainage generally agreed well with measurements of streamflow, although estimated annual drainage (349 mm year(-1), 24%) exceeded measured streamflow (234 mm year(-1)). The significance of the results is discussed in relation to closure of the hydrologic balance. PMID:14972854

  13. Co-evolution of volcanic catchments in Japan

    NASA Astrophysics Data System (ADS)

    Yoshida, T.; Troch, P. A.

    2015-09-01

    Present day landscapes have evolved over time through interactions between the prevailing climates and geological settings. Understanding the linkage between spatial patterns of landforms, soils, and vegetation in landscapes and their hydrological response is critical to make quantitative predictions in ungaged basins. Catchment co-evolution is a theoretical framework that seeks to formulate hypotheses about the mechanisms and conditions that determine the historical development of catchments and how such evolution affects their hydrological response. In this study, we selected 14 volcanic catchments of different ages (from 0.225 to 82.2 Ma) in Japan. We derived indices of landscape properties (drainage density) as well as hydrological response (annual water balance, baseflow index, and flow duration curves) and examined their relation with catchment age and climate (through the aridity index). We found significant correlation between drainage density and baseflow index with age, but not with climate. The age of the catchments was also significantly related to intra-annual flow variability. Younger catchments tend to have lower peak flows and higher low flows, while older catchments exhibit more flashy runoff. The decrease of baseflow with catchment age confirms previous studies that hypothesized that in volcanic landscapes the major flow pathways have changed over time, from deep groundwater flow to shallow subsurface flow. The drainage density of our catchments decreased with age, contrary to previous findings in similar volcanic catchments but of significant younger age than the ones explored here. In these younger catchments, an increase in drainage density with age was observed, and it was hypothesized that this was because of more landscape incision due to increasing near-surface lateral flow paths in more mature catchments. Our results suggests two hypotheses on the evolution of drainage density in matured catchments. One is that as catchments further evolve

  14. Hydrological modelling of urbanized catchments: A review and future directions

    NASA Astrophysics Data System (ADS)

    Salvadore, Elga; Bronders, Jan; Batelaan, Okke

    2015-10-01

    In recent years, the conceptual detail of hydrological models has dramatically increased as a result of improved computational techniques and the availability of spatially-distributed digital data. Nevertheless modelling spatially-distributed hydrological processes can be challenging, particularly in strongly heterogeneous urbanized areas. Multiple interactions occur between urban structures and the water system at various temporal and spatial scales. So far, no universal methodology exists for simulating the urban water system at catchment scale. This paper reviews the state of the art on the scientific knowledge and practice of modelling the urban hydrological system at the catchment scale, with the purpose of identifying current limitations and defining a blueprint for future modelling advances. We compare conceptual descriptions of urban physical hydrological processes on basis of a selection of 43 modelling approaches. The complexity of the urban water system at the catchment scale results in an incomplete understanding of the interaction between urban and natural hydrological systems, and in a high degree of uncertainty. Data availability is still a strong limitation since current modelling practice recognizes the need for high spatial and temporal resolution. Spatio-temporal gaps exist between the physical scales of hydrological processes and the resolution of applied models. Therefore urban hydrology is often simplified either as a study of surface runoff over impervious surfaces or hydraulics of piped systems. Many approaches target very specific objectives and the level of detail in representing physical processes is not consistent. Based on our analysis, we propose a blueprint for a highly complex integrated urban hydrological model. We regard flexibility, in terms of model structure and data assimilation, as the key characteristic for overcoming these limitations. We advocate the use of modular, process-based approaches, which are flexible and adaptable

  15. Hydrological improvements for nutrient and pollutant emission modeling in large scale catchments

    NASA Astrophysics Data System (ADS)

    Höllering, S.; Ihringer, J.

    2012-04-01

    hydrological system is simulated spatially differentiated and emissions from urban and rural areas into river courses can be detected separately. In the Ruhr catchment (4.485 km2) as a right tributary of the Rhine located in the lower mountain range of North Rhine-Westphalia in Germany for the validation period 2002-2006 the hydrological model showed first satisfying results. The feasibility study in the Ruhr shows the suitability of the approach and illustrates the potentials for further developments in terms of an implementation throughout the German and contiguous watersheds. IWG, Karlsruhe Institute of Technology (KIT). 2011. http://isww.iwg.kit.edu/MoRE.php. [Online] Institute for Water and River Basin Management, Department of Aquatic Environmental Engineering, October 2011. USGS, U.S. Geological Survey. 2009. PRMS-2009, the Precipitation-Runoff Modeling System. Denver, Colorado : s.n., 2009. Bd. U.S. Geologic Survey Open File Report.

  16. Advances in catchment scale bank erosion modelling - quantifying the improved representation of temporal and spatial variability

    NASA Astrophysics Data System (ADS)

    Janes, Victoria; Holman, Ian; O'Donnell, Greg; Birkinshaw, Stephen; Kilsby, Chris

    2015-04-01

    Channel bank erosion processes are influenced by numerous factors resulting in high spatial and temporal variability of sediment production. The representation of channel bank erosion is overly simplistic within most catchment models, despite its significance to catchment sediment budgets. Within this study, the physically-based distributed SHETRAN model is modified to incorporate bank vegetation and channel sinuosity factors that influence spatial and temporal bank erosion rates. The modified model simulates the temporal variation of bank erosion in response to high magnitude events with the potential to remove bank vegetation and de-stabilise banks, thereby increasing erodibility. As vegetation re-establishes, simulated bank erodibility decreases. During the recovery period, banks have increased vulnerability to further high magnitude events that will result in increased bank erosion. This enables the model to represent the impact of flood clustering on sediment generation. The modified model also represents the spatial variation of bank erosion as a result of varying channel planform. Channel geometry has also been linked to bank erosion rates as a result of flow circulation within channels. Channel sinuosity shows a non-linear relationship with bank erosion, with bank erosion increasing up to a threshold value of sinuosity and decreasing as sinuosity increases above this point. The original and modified models have been applied to the Eden catchment in north east England. Bank erosion data derived from a GIS overlay methodology covering 150 years has been used to validate the models, indicating annual sediment generation from bank erosion processes within the catchment is 410-4500 t yr-1, equivalent to 2-11% of the catchment sediment budget. Comparison of the original and modified models highlights the improved ability of the modified model to simulate annual variation of bank eroded sediment production; annual sediment production from the original model ranged

  17. Ecosystem Services Derived from Headwater Catchments

    EPA Science Inventory

    We used data from the USEPA’s wadeable streams assessment (WSA), US Forest Service’s forest inventory and analysis (FIA), and select USFS experimental forests (EF) to investigate potential ecosystems services derived from headwater catchments. C, N, and P inputs to these catchmen...

  18. Geomorphic histories for river and catchment management.

    PubMed

    Wasson, R J

    2012-05-13

    River and catchment management usually proceeds from the identification of an undesirable state (e.g. pollution, sedimentation, excessive water extraction, dams, invasion by exotic species) to a strategy for reaching a desirable state described as a target. Desirable states are usually determined from community values, economic assessments and ecosystem functions, or a combination of these. Where a catchment is highly disturbed, the target is usually not a natural state, as that cannot be achieved while maintaining human uses, and a history is needed to document the disturbance, understand its cause and define the 'existence space', that is, the range of natural states that have occurred in the past. Where a catchment is less disturbed, a former natural state could provide a target for management. But which of the many natural (equilibrium) states that have occurred in the past should be the target? The paper reviews what is known of the quantitative difference between pre- and post-disturbance states, searches for the presence or otherwise of equilibrium and comments on the utility of this information for catchment management. The focus is on erosion and sediment transport. PMID:22474683

  19. Measuring winter precipitation in a mountain catchment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Measuring winter precipitation (principally snowfall) in a mountain catchment is difficult. The magnitude of gauge under catch is affected by variable density during deposition, wind speed and direction, and site conditions such as vegetation and topography. Though numerous studies have been condu...

  20. Catchment management and the Great Barrier Reef.

    PubMed

    Brodie, J; Christie, C; Devlin, M; Haynes, D; Morris, S; Ramsay, M; Waterhouse, J; Yorkston, H

    2001-01-01

    Pollution of coastal regions of the Great Barrier Reef is dominated by runoff from the adjacent catchment. Catchment land-use is dominated by beef grazing and cropping, largely sugarcane cultivation, with relatively minor urban development. Runoff of sediment, nutrients and pesticides is increasing and for nitrogen is now four times the natural amount discharged 150 years ago. Significant effects and potential threats are now evident on inshore reefs, seagrasses and marine animals. There is no effective legislation or processes in place to manage agricultural pollution. The Great Barrier Reef Marine Park Act does not provide effective jurisdiction on the catchment. Queensland legislation relies on voluntary codes and there is no assessment of the effectiveness of the codes. Integrated catchment management strategies, also voluntary, provide some positive outcomes but are of limited success. Pollutant loads are predicted to continue to increase and it is unlikely that current management regimes will prevent this. New mechanisms to prevent continued degradation of inshore ecosystems of the Great Barrier Reef World Heritage Area are urgently needed. PMID:11419129

  1. Development of soil quality along a chronosequence under natural succession in the Dragonja catchment, SW Slovenia

    NASA Astrophysics Data System (ADS)

    van Hall, Rutger; Cammeraat, Erik

    2015-04-01

    Agricultural fields have been increasingly abandoned in several regions in Southern Europe. In many cases this leads to natural vegetation succession which may have a direct impact on soil quality,biodiversity and hydrological connectivity. This research aims at getting insight on the effects of natural vegetation succession on the development of soil quality in the Sub-Mediterranean Dragonja catchment in SW Slovenia. This site was chosen due to its uniform geology, geomorphology and soil types. Four different stages of vegetation succession (i.e. field, abandoned field, young forest, semi-mature forest) were selected and sampled on both north-, and south-facing slopes, resulting in 8 treatments for which 6 representative sites were sampled. Samples were analysed on OC and TN content, EC, pH, bulk density, aggregate stability and grain size distribution. To get insight on the changes in biodiversity vegetation records were made distinguishing five different plant functional groups (i.e. juveniles, grasses, herbs, shrubs and trees). Age group (i.e. stage of vegetation succession) significantly influenced the OC and TN content, aggregate stability, bulk density and pH. Directly after abandonment, between age group 0 and 1, OC and TN content, aggregate stability and pH increased significantly and bulk density decreased significantly. OC content was most affected by age group and furthermore significantly correlated to TN content, aggregate stability, bulk density and pH. Regarding biodiversity, there was a significant increase in cover by trees between age group 1 and 2 and a significant decrease between age group 2 and 3. Cover by herbs decreased significantly between age group 1 and 2. The number of different trees and shrubs increased significantly between age group 0 and 1, and the number of different juveniles increased significantly between age group 2 and 3. Another factor significantly influencing the soil's quality is aspect. Although not found for each age

  2. WORKSHOP REPORT: COMPUTATIONAL TOXICOLOGY: FRAMEWORK, PARTNERSHIPS, AND PROGRAM DEVELOPMENT, SEPTEMBER 29-30, 2003, RESEARCH TRIANGLE PARK, NORTH CAROLINA

    EPA Science Inventory

    Computational toxicology is a new research initiative being developed within the Office of Research and Development (ORD) of the US Environmental Protection Agency (EPA). Operationally, it is defined as the application of mathematical and computer models together with molecular c...

  3. Catchment scale afforestation for mitigating flooding

    NASA Astrophysics Data System (ADS)

    Barnes, Mhari; Quinn, Paul; Bathurst, James; Birkinshaw, Stephen

    2016-04-01

    After the 2013-14 floods in the UK there were calls to 'forest the uplands' as a solution to reducing flood risk across the nation. At present, 1 in 6 homes in Britain are at risk of flooding and current EU legislation demands a sustainable, 'nature-based solution'. However, the role of forests as a natural flood management technique remains highly controversial, due to a distinct lack of robust evidence into its effectiveness in reducing flood risk during extreme events. SHETRAN, physically-based spatially-distributed hydrological models of the Irthing catchment and Wark forest sub-catchments (northern England) have been developed in order to test the hypothesis of the effect trees have on flood magnitude. The advanced physically-based models have been designed to model scale-related responses from 1, through 10, to 100km2, a first study of the extent to which afforestation and woody debris runoff attenuation features (RAFs) may help to mitigate floods at the full catchment scale (100-1000 km2) and on a national basis. Furthermore, there is a need to analyse the extent to which land management practices, and the installation of nature-based RAFs, such as woody debris dams, in headwater catchments can attenuate flood-wave movement, and potentially reduce downstream flood risk. The impacts of riparian planting and the benefits of adding large woody debris of several designs and on differing sizes of channels has also been simulated using advanced hydrodynamic (HiPIMS) and hydrological modelling (SHETRAN). With the aim of determining the effect forestry may have on flood frequency, 1000 years of generated rainfall data representative of current conditions has been used to determine the difference between current land-cover, different distributions of forest cover and the defining scenarios - complete forest removal and complete afforestation of the catchment. The simulations show the percentage of forestry required to have a significant impact on mitigating

  4. Evaluating an ecosystem management approach for improving water quality in two contrasting study catchments in south-west England.

    NASA Astrophysics Data System (ADS)

    Glendell, Miriam; Brazier, Richard

    2014-05-01

    The European Water Framework Directive (WFD) 2000 established a new emphasis for the management of freshwaters by establishing ecologically-based water quality targets that are to be achieved through holistic, catchment-scale, ecosystem management approaches. However, significant knowledge gaps still exist in the understanding of the cumulative effectiveness of multiple mitigation measures on a number of pollutants at a catchment scale. This research furthers the understanding of the effectiveness of an ecosystem management approach to deliver catchment-scale water quality improvements in two contrasting study catchments in south-west England: the lowland agricultural Aller and the upland semi-natural Horner Water. Characterisation of the spatial variability of soil properties (bulk density, total carbon, nitrogen, C:N ratio, stable isotope δ15N, total, organic and inorganic phosphorus) in the two study catchments demonstrated extensive alteration of soil properties in the agricultural catchment, with likely long-term implications for the restoration of ecosystem functioning and water quality management (Glendell et al., 2014b). Further, the agricultural catchment supported a proportionally greater total fluvial carbon (dissolved and particulate) export than the semi-natural catchment. During an eight month period for which a comparable continuous turbidity record was available, the estimated SS yields from the agricultural catchment (25.5-116.2 t km-2) were higher than from the semi-natural catchment (21.7-57.8 t km-2). In addition, the agricultural catchment exported proportionally more TPC (0.51-2.59 kg mm-1) than the semi-natural catchment (0.36-0.97 kg mm-1) and a similar amount of DOC (0.26-0.52 kg mm-1 in the Aller and 0.24-0.32 kg mm-1 in Horner Water), when normalised by catchment area and total discharge, despite the lower total soil carbon pool, thus indicating an enhanced fluvial loss of sediment and carbon (Glendell and Brazier, in review). Whilst

  5. Response of current phosphorus mitigation measures across the nutrient transfer continuum in two hydrological contrasting agricultural catchments

    NASA Astrophysics Data System (ADS)

    McDonald, Noeleen; Shore, Mairead; Mellander, Per-Erik; Shortle, Ger; Jordan, Phil

    2015-04-01

    Effective assessment of National Action Programme (NAP) measures introduced under the EU Nitrates Directive (ND), to manage nutrient use and risk of loss to waters from agriculture, is best achieved when examined across the nutrient transfer continuum at catchment scale. The Irish NAP measures are implemented on a whole-territory basis for both nitrogen (N) and phosphorus (P), with P being the key trophic pressure. The aim of this research was to observe the efficacy of P regulation measures and P source management across the transfer continuum and resultant water quality status (i.e. source to impact), in two contrasting agricultural catchments over a four year period. The catchments are ca. 11 km2 and are located in the south-east of Ireland. One is well-drained and arable dominated, while the other is mostly poorly-drained and grassland dominated. In 2009 and 2013 soil surveys for plant-available P were carried out (<2 ha sample areas) in both catchments. Concurrently, high temporal resolution monitoring of water discharge and P concentration was conducted at each catchment outlet across four hydrological years (April to March). Ecological impact surveys were carried out at four sites within each catchment in May and September across the observed four year period (2009-2013). Importantly, the proportion of farmland with excessive soil P concentrations decreased in both the arable (20% to 11.8%) and grassland catchments (5.9 to 3.6%). However, soil P concentrations also declined critically in both catchments, as proportional areas below the national crop agronomic optimum thresholds (grassland; <5 mg P l-1, arable; <6 mg P l-1) increased from 57% to 68% in the arable catchment and 75% to 87% in the grassland catchment. This decline in plant available P strongly indicates a reduced or sustained level of P inputs in both catchments. Indications of responses to soil P change in the surface waters of these catchments appeared to be highly influenced by their

  6. A mediated modelling approach to promote collaborative learning in Andean rural micro-catchments in Colombia

    NASA Astrophysics Data System (ADS)

    Gowing, John; Dominguez, Isabel

    2013-04-01

    In rural catchments of developing countries water-related diseases, due to land use patterns (agriculture and livestock), microbial pollution, inadequate sanitation systems, access to water of poor quality, and lack of institutional support are common problems which disproportionally affect poor and vulnerable people. This research aims at developing a system dynamic model to improve the understanding of the macro and micro factors that influence human health and environmental health in rural micro-catchments in Valle del Cauca, Colombia. In this catchment livelihoods for most people depend on agriculture, particularly coffee. The research uses a mediated modeling approach, in which different stakeholders in modeling sessions, develop a STELLA model that allows them to identify relations between the economic, social and environmental factors and driving forces over the performance of their system. Stakeholders jointly develop the model structure in sessions facilitated by the researcher and the data required is gathered using secondary information from the different relevant institutions and primary information from field surveys that cover socioeconomic and environmental aspects that has not been previously collected by any institution or organization (i.e. household survey, stream water survey, and drinking water survey). Representation and understanding of their system will allow the stakeholders to test the effect of different management strategies in the micro-catchment and their associated socioeconomic, environmental and human health outcomes.

  7. Integration of NASA Research into Undergraduate Education in Math, Science, Engineering and Technology at North Carolina A&T State University

    NASA Technical Reports Server (NTRS)

    Monroe, Joseph; Kelkar, Ajit

    2003-01-01

    The NASA PAIR program incorporated the NASA-Sponsored research into the undergraduate environment at North Carolina Agricultural and Technical State University. This program is designed to significantly improve undergraduate education in the areas of mathematics, science, engineering, and technology (MSET) by directly benefiting from the experiences of NASA field centers, affiliated industrial partners and academic institutions. The three basic goals of the program were enhancing core courses in MSET curriculum, upgrading core-engineering laboratories to compliment upgraded MSET curriculum, and conduct research training for undergraduates in MSET disciplines through a sophomore shadow program and through Research Experience for Undergraduates (REU) programs. Since the inception of the program nine courses have been modified to include NASA related topics and research. These courses have impacted over 900 students in the first three years of the program. The Electrical Engineering circuit's lab is completely re-equipped to include Computer controlled and data acquisition equipment. The Physics lab is upgraded to implement better sensory data acquisition to enhance students understanding of course concepts. In addition a new instrumentation laboratory in the department of Mechanical Engineering is developed. Research training for A&T students was conducted through four different programs: Apprentice program, Developers program, Sophomore Shadow program and Independent Research program. These programs provided opportunities for an average of forty students per semester.

  8. Predominant Runoff Components During Heavy Rainfall Events on Cultivated Catchment

    NASA Astrophysics Data System (ADS)

    Jeřábek, J.; Zumr, D.; Strouhal, L.

    2015-12-01

    The fact that flash floods initiated in arable catchments are often accompanied by massive sediment and nutrient loads often leads to the assumption that surface runoff is the principle pathway by which runoff reaches watercourses. But the hydrology of cultivated catchments has its specific features due to the temporary variable topsoil properties and a sharp divide between topsoil and compacted subsoil. Under various conditions the prevailing runoff mechanisms may vary from surface runoff to subsurface runoff or deep percolation. On the basis of an evaluation of several rainfall-runoff events in a representative agricultural catchment (Nucice, Czech Republic), we show that runoff from cultivated land may be generated in a way similar to that seen on forested slopes, where shallow subsurface runoff is the predominant pathway. To identify the predominant runoff pathway, we employed a combination of turbidity measurements and stream discharge data. Although we observed temporal variability of topsoil properties attributable to seasonal weather changes and agricultural activities, e.g. bulk density and porosity, runoff generation was mainly driven by precipitation characteristics and the initial catchment saturation. The concept of the runoff formation was also observed during plot scale experiments with rainfall simulator. Various initial soil moisture conditions, and vegetation stages delimited the simulations. Variable proportions of both monitored runoff components were observed in relation to rainfall intensity and duration, ranging from zero surface runoff to a distinct dominance of surface runoff. Even with the highest tested precipitation intensities, surface runoff always formed due to saturation excess of the topsoil, irrespective of the topsoil properties and crops. The experiments were numerically modelled and analysed to understand the effect of temporal variability in the macropores and intra-aggregate voids ratio within the topsoil. We used a

  9. The artifcial catchment Chicken Creek as a tool to study initial ecosystem development

    NASA Astrophysics Data System (ADS)

    Schaaf, W.; Elmer, M.; Fischer, A.; Gerwin, W.; Nenov, R.

    2011-12-01

    The artificial catchment Chicken Creek was constructed in 2005 to study the increasingly complex interactions of processes and structures during initial development of ecosystems. The 6ha area serves as the central research site for the Transregional Collaborative Research Center 38. Both internal and external factors could be identified as driving forces for the formation of structures and patterns in the artificial catchment during the first five years of development. Initial structures formed by the construction process (e.g. catchment morphology, subsurface structures like clay dams and dumping cones, caterpillar tracks at the surface) and initial substrate characteristics (e.g. texture, geochemistry) were decisive both for the distribution and flow of precipitation water and for vegetation succession. External factors like episodic events (e.g. heavy thunderstorms) triggered erosion and dissection during this initial phase, promoted by the low vegetation cover and the unconsolidated sandy substrate. These processes resulted in transport and redistribution of water and sediment within the catchment, mainly along the main slope, and the formation of new structural elements like gullies and channels, a sedimentation fan above and sediments within the pond. As a result, we observed an overall differentiation of the site, e.g. with respect to water availability and texture redistribution, into areas with abrasion or accumulation processes dominating and areas with stable surfaces. During further development, both external factors and processes within the catchment continued to influence the site. For example, beside the initial soil seed bank, the surrounding environment of the catchment clearly affected species invasion. The dissection and stability of surfaces may be an important factor for the establishment of plants and habitats as well as for the formation of vegetation patterns and biological soil crusts. The transformation of the initial geo-system into

  10. Hydrology Research with the North American Land Data Assimilation System (NLDAS) Datasets at the NASA GES DISC Using Giovanni

    NASA Technical Reports Server (NTRS)

    Mocko, David M.; Rui, Hualan; Acker, James G.

    2013-01-01

    The North American Land Data Assimilation System (NLDAS) is a collaboration project between NASA/GSFC, NOAA, Princeton Univ., and the Univ. of Washington. NLDAS has created a surface meteorology dataset using the best-available observations and reanalyses the backbone of this dataset is a gridded precipitation analysis from rain gauges. This dataset is used to drive four separate land-surface models (LSMs) to produce datasets of soil moisture, snow, runoff, and surface fluxes. NLDAS datasets are available hourly and extend from Jan 1979 to near real-time with a typical 4-day lag. The datasets are available at 1/8th-degree over CONUS and portions of Canada and Mexico from 25-53 North. The datasets have been extensively evaluated against observations, and are also used as part of a drought monitor. NLDAS datasets are available from the NASA GES DISC and can be accessed via ftp, GDS, Mirador, and Giovanni. GES DISC news articles were published showing figures from the heat wave of 2011, Hurricane Irene, Tropical Storm Lee, and the low-snow winter of 2011-2012. For this presentation, Giovanni-generated figures using NLDAS data from the derecho across the U.S. Midwest and Mid-Atlantic will be presented. Also, similar figures will be presented from the landfall of Hurricane Isaac and the before-and-after drought conditions of the path of the tropical moisture into the central states of the U.S. Updates on future products and datasets from the NLDAS project will also be introduced.

  11. What can we learn from the hydrological modeling of small-scale catchments for the discharge and water balance modeling of mesoscale catchments?

    NASA Astrophysics Data System (ADS)

    Cornelissen, Thomas; Diekkrüger, Bernd; Bogena, Heye

    2015-04-01

    The application of 3D hydrological models remains a challenge both in research and application studies because the parameterization not only depends on the amount and quality of data available for calibration and validation but also on the spatial and temporal model resolution. In recent years, the model parameterization has improved with the availability of high resolution data (e.g. eddy-covariance, wireless soil sensor networks). Unfortunately, these high resolution data are typically only available for small scale research test sites. This study aims to upscale the parameterization from a highly equipped, small-scale catchment to a mesoscale catchment in order to reduce the parameterization uncertainty at that scale. The two nested catchments chosen for the study are the 0.38 km² large spruce covered Wüstebach catchment and the 42 km² large Erkensruhr catchment characterized by a mixture of spruce and beech forest and grassland vegetation. The 3D hydrogeological model HydroGeoSphere (HGS) has already been setup for the Wüstebach catchment in a previous study with a focus on the simulation performance of soil water dynamics and patterns. Thus, the parameterization process did not only optimize the water balance components but the catchment's wireless soil sensor network data were utilized to calibrate porosities in order to improve the simulation of soil moisture dynamics. In this study we compared different HGS model realizations for the Erkensruhr catchment with different input data. For the first model realization, the catchment is treated heterogeneous in terms of soil properties and topography but homogeneous with respect to land use, precipitation and potential evapotranspiration. For this case, the spruce forest parameterization and the climate input data were taken directly from the small-scale Wüstebach model realization. Next, the calibrated soil porosity for the Wüstebach catchment is applied to the Erkensruhr. Further model realizations

  12. Characterising water balance dynamics and different runoff components in a poorly gauged tropical catchment, Nicaragua

    NASA Astrophysics Data System (ADS)

    Calderon, Heyddy; Uhlenbrook, Stefan

    2014-05-01

    The water balance dynamics, groundwater flow systems and the runoff components of a tropical forested small catchment (46 km2) is the southwestern Pacific coast of Nicaragua were studied by a combination of hydrometry (observation of rainfall, runoff, evaporation and groundwater levels), geological characterisation (hydrogeological mapping, flow systems, characterization and Piper diagrams) and hydrochemical and isotopic tracers (chemograph analysis, 2- and 3-component hydrograph separation, discharge-hydrochemical hysteresis effects, and MWL). Although some methods can be considered standard in runoff generation research in temperate climate regions; to the best of our knowledge, this is one of the few studies that used the combination of these techniques in a tropical catchment of Central America. Runoff components were studied at different spatial and temporal scales, finding that different sources and temporal contributions are controlled by geology, catchment size, and dominant landscape elements. Two major groundwater flow systems were identified with different chemical and isotopic characteristics. Indication of moisture recycling in the upper catchment area was found based on d-excess analysis. Runoff components were studied at different spatial and temporal scales, demonstrating that different sources and temporal contributions are controlled by dominant landscape elements and precipitation distribution. Evidence of strong river-aquifer interactions in the lower part of the catchment was found. The results provide an in-depth understanding of the surface and groundwater contributions to stream flow and its temporal and spatial distribution, which indicate the importance of runoff generation areas upstream in the catchment and also the vulnerability of the alluvial aquifer to contamination. This provides the basis to develop realistic, evidence-based water management plans for this developing region.

  13. Physical and biological controls on reach to catchment scale nutrient retention and streamwater composition

    NASA Astrophysics Data System (ADS)

    Covino, T. P.; McGlynn, B. L.; Wohl, E.

    2014-12-01

    Physical and biological processes occurring within fluvial networks can have strong influence on catchment scale retention of water and nutrients. Quantifying the physical (i.e., hydrologic exchange) and biological (i.e., nutrient uptake) contributions to total retention and deciphering how they relate to catchment morphology remains a central challenge in the hydrologic and biogeo-sciences. Here we present examples from our research that highlight the interactions between biology, physical hydrology, and geomorphology and how they combine to influence nutrient retention and streamwater compositions. Biological nutrient uptake in streams can have substantial influence on downstream fluxes and induce nutrient transformation along stream networks. Additionally, hydrologic loss of water and associated nutrients from streams to surrounding groundwater systems can greatly elongate water and nutrient retention times. While in-stream nutrient uptake is often associated with hyporheic exchanges that occur at sub-meter scales, these are nested within a larger framework of fluvial exchanges (100s - 1000s of meters). Larger scale exchanges can lead to strong shifts in streamwater composition over relatively short spatial scales (~1km) and are often very pronounced along geomorphic transitions (e.g., mountain to valley) and/or catchment retention zones (e.g., alluvial aquifers, wetlands, lakes). In fact, 50 - 80% of the water in the channel can be exchanged and replaced by different water (i.e., groundwater) along geomorphic transitions/catchment retention zones that are ~1 km in scale. These features can enhance geochemical processing through extended interactions between water, sediment, and nutrients. Accordingly, we suggest that although catchment retention features may be limited in spatial extent (~1km) and frequency they have the capacity to play a disproportionately large role in controlling catchment retention dynamics and setting fluvial network streamwater

  14. Informing Hydrological Drought Response in Headwater Catchments Using Water Storage Estimated From GRACE: Storage-Flow Dynamics

    NASA Astrophysics Data System (ADS)

    Gaffney, R.; Tyler, S. W.; Harpold, A. A.; Volk, J. M.

    2015-12-01

    Quantifying the relationship between subsurface water storage and streamflow is challenging due to heterogeneity of surface-groundwater interactions in space and time. Hence, point measurements of storage from wells are insufficient to characterize the storage across a catchment, especially in mountainous environments with complex geology. Here, we present a novel approach to quantify the storage-flow relationship for catchments in the Sierra Nevada Mountains. For 23 gages in the Hydro-Climatic Data Network, the 7-day average annual minimum flow (drought flow) was computed for years 2003 to 2015. We then aggregated, for each gage, the associated storage time-series dataset from 1o gridded measurements of monthly Terrestrial Water Storage (TWS) derived from the Gravity Recovery and Climate Experiment (GRACE) satellite mission. Despite the significant mismatch between the spatial scales and temporal resolution, we found a strong empirical correlation between TWS and drought flow. From these relationships, we examined how physical characteristics of each catchment (such as size and geology) impact the observed nonlinear relationship between TWS and drought flow. Furthermore, we show how physical characteristics, such as geology/storage capacity, of catchments affect the sensitivity of decreasing flows to multi-year droughts. This research has the potential to help better quantify the streamflow-storage relationship in small mountainous catchments, as well as, classify catchments that may be more vulnerable to decreasing flows with multi-year droughts.

  15. Effect of bedrock permeability on stream base flow mean transit time scaling relations: 1. A multiscale catchment intercomparison

    NASA Astrophysics Data System (ADS)

    Hale, V. Cody; McDonnell, Jeffrey J.

    2016-02-01

    The effect of bedrock permeability and underlying catchment boundaries on stream base flow mean transit time (MTT) and MTT scaling relationships in headwater catchments is poorly understood. Here we examine the effect of bedrock permeability on MTT and MTT scaling relations by comparing 15 nested research catchments in western Oregon; half within the HJ Andrews Experimental Forest and half at the site of the Alsea Watershed Study. The two sites share remarkably similar vegetation, topography, and climate and differ only in bedrock permeability (one poorly permeable volcanic rock and the other more permeable sandstone). We found longer MTTs in the catchments with more permeable fractured and weathered sandstone bedrock than in the catchments with tight, volcanic bedrock (on average, 6.2 versus 1.8 years, respectively). At the permeable bedrock site, 67% of the variance in MTT across catchments scales was explained by drainage area, with no significant correlation to topographic characteristics. The poorly permeable site had opposite scaling relations, where MTT showed no correlation to drainage area but the ratio of median flow path length to median flow path gradient explained 91% of the variance in MTT across seven catchment scales. Despite these differences, hydrometric analyses, including flow duration and recession analysis, and storm response analysis, show that the two sites share relatively indistinguishable hydrodynamic behavior. These results show that similar catchment forms and hydrologic regimes hide different subsurface routing, storage, and scaling behavior—a major issue if only hydrometric data are used to define hydrological similarity for assessing land use or climate change response.

  16. Rainfall Threshold For Slope-Channel Connectivity In Agricultural Catchment

    NASA Astrophysics Data System (ADS)

    Święchowicz, Jolanta

    2015-04-01

    Many rainfall events lead to the transfer of soil material from one slope section to another, which does not notably alter slope relief (first transfer threshold). Some events lead to the transfer of soil from the water divide to the footslope (second transfer threshold). In a few exceptional cases, soil material is transferred directly into river channels due to severe erosion moving large quantities of soil over long distances. Extreme events lead to the transfer of soil material down the entire slope length, its deposition at the footslope and even further across the valley floor. Sediment is transferred directly from slopes to river channels (third transfer threshold or slope-channel connectivity threshold). This work presents rainfall threshold values and probability of slope-to-river sediment transfer in a foothill agricultural catchment in Poland. The study is based on research performed in the Dworski Potok Catchment (227-275 m a.s.l.), which is a small agricultural foothill catchment (0.29 km2), situated in a moderate climate zone, with slopes covered with loess-like formations. The paper uses precipitation data for the period 1987-2009 obtained at the Łazy Field Research Station near Bochnia (Poland) and long-term field data on splash (2007-2009), slope wash (2007-2009) and linear erosion (1998-2009) on slopes. In Dworski Potok Catchment change in the slope relief was brought about by short transformation periods, during which soil erosion by water took place, especially if it was caused by events of high magnitude and low frequency. Those periods which, depending on the criterion adopted, lasted from 0.3 to 4% of the time of study were the most interesting and effective episodes in the development of slopes. It was determined that in the researched multi-year period, the transfer of soil material was possible to occur after certain parameters had exceeded the following threshold values: EI30 = 40.5 MJmmha-1h-1 or I30 = 9.8 mmh-1 for the first transfer

  17. Response of surface and groundwater on meteorological drought in Topla River catchment, Slovakia

    NASA Astrophysics Data System (ADS)

    Fendekova, Miriam; Fendek, Marian; Vrablikova, Dana; Blaskovicova, Lotta; Slivova, Valeria; Horvat, Oliver

    2016-04-01

    Continuously increasing number of drought studies published in scientific journals reflects the attention of the scientific community paid to drought. The fundamental works among many others were published by Yevjevich (1967), Zelenhasic and Salvai (1987), later by Tallaksen and van Lanen Eds. (2004). The aim of the paper was to analyze the response of surface and groundwater to meteorological drought occurrence in the upper and middle part of the Topla River Basin, Slovakia. This catchment belongs to catchments with unfavourable hydrogeological conditions, being built of rocks with quite low permeability. The basin is located in the north-eastern part of Slovakia covering the area of 1050.05 km2. The response was analyzed using precipitation data from the Bardejov station (long-term annual average of 662 mm in 1981 - 2012) and discharge data from two gauging stations - Bardejov and Hanusovce nad Toplou. Data on groundwater head from eight observation wells, located in the catchment, were also used, covering the same observation period. Meteorological drought was estimated using characterisation of the year humidity and SPI index. Hydrological drought was evaluated using the threshold level method and method of sequent peak algorithm, both with the fixed and also variable thresholds. The centroid method of the cluster analysis with the squared Euclidean distance was used for clustering data according to occurrence of drought periods, lasting for 100 days and more. Results of the SPI index showed very good applicability for drought periods identification in the basin. The most pronounced dry periods occurred in 1982 - 1983, 1984, 1998 and 2012 being classified as moderately dry, and also in 1993 - 1994, 2003 - 2004 and 2007 evolving from moderately to severely dry years. Short-term drought prevailed in discharges, only three periods of drought longer than 100 days occurred during the evaluated period in 1986 - 1987, 1997 and 2003 - 2004. Discharge drought in the

  18. Hydrogeochemical signatures of catchment evolution - the role of calcium and sulphate release in the constructed Hühnerwasser ("Chicken Creek") catchment

    NASA Astrophysics Data System (ADS)

    Pohle, Ina; Hu, Yuzhu; Schaaf, Wolfgang; Gerwin, Werner; Hinz, Christoph

    2016-04-01

    The constructed Hühnerwasser ("Chicken Creek") catchment is an ecohydrological system in an initial state of development. The catchment with an area of 6 ha was built up from quaternary sediments in the post-mining landscape of Lusatia in Eastern Germany and serves as a critical zone observatory for detecting ecosystem transition. The soil substrate is characterized as sands to loamy sands with low carbonate contents but significant amounts of gypsum in the sediments of the catchment. The catchment undergoes a strong transition from an abiotic system in the initial years to a system with growing influence of biota. Concerning the hydrology, a regime shift from surface runoff to groundwater flow dominated processes is significant. It is of interest, whether the catchment transition is also reflected by hydrogeochemical indicators. We assume gypsum dissolution as dominant process at the catchment scale. In order to investigate the hydrogeochemical evolution of the catchment we analysed electric conductivity, calcium and sulphate concentrations and pH-values of biweekly composite samples from 2007-2013 of the atmospheric deposition, of runoff and soil water. The two observation points in the flowing water represent surface runoff and groundwater discharge respectively. Soil water has been analysed at four soil pits in three depths. The monitoring data were provided by the Research Platform Chicken Creek (https://www.tu-cottbus.de/projekte/en/oekosysteme/startseite.html). From the macroscopic data analysis we found an exponential decay of the electric conductivity, calcium and sulphate concentrations in the flowing waters and some of the soil pits. In the flowing water, the decrease slope of the electric conductivity and the calcium and sulphate concentrations is almost identical. The calcium / sulphate molar ratio as an indicator of gypsum dissolution is almost equal to one up to 2010, afterwards more calcium than sulphate is released. The pH-values in the flowing

  19. Using high resolution water quality monitoring across three English catchments to capture a storm event during a transition from dry to wet conditions

    NASA Astrophysics Data System (ADS)

    Outram, F.; Lloyd, C.; Jonczyk, J.; Benskin, C.; Grant, F.

    2013-12-01

    The Demonstration Test Catchment (DTC) project is a UK government funded initiative to test the effectiveness of on-farm mitigation measures designed to reduce agricultural pollution without compromising farm productivity. Three distinct catchments in England have been chosen to test mitigation measures on working farms in small tributary catchments equipped with continuous water quality monitoring stations. The River Avon in the south is a chalk and sandstone catchment with livestock and arable farming, the River Wensum in the east is a lowland chalk catchment with predominantly arable farming and the River Eden in the North has a limestone and sandstone geology with predominantly livestock farming. One of the many strengths of the DTC as a national programme is that it provides the ability to investigate catchment hydrology and biogeochemical response across three different English landscapes. This is a collaborative paper involving members of all three DTC consortia, which aims to compare the responses of each of the catchments to a single storm event from April 2012, which was as a result of one of the first weather fronts to track across the country following a drought period affecting much of the UK, producing heavy rainfall in all three catchments. This was an unusual meteorological period, with subsequent hydrological implications when a rapid shift from drought to flood risk occurred across parts of the country. The effects of the weather front on discharge and water chemistry parameters, including N (NO3- and NH4), P (Total P (TP) and Total Reactive P (TRP)), dissolved oxygen (DO), chlorophyll and turbidity, measured at a half-hourly time step, are examined. When considered in the context of one hydrological year, flow and concentration duration curves reveal that the weather fronts resulted in extreme flow, nitrate and TP concentrations in all three catchments but with distinct differences in hydrograph and nutrient response. Hysteresis loops constructed

  20. COMPUTATIONAL TOXICOLOGY: FRAMEWORK, PARTNERSHIPS, AND PROGRAM DEVELOPMENT. SEPTEMBER 29-30, 2003, RESEARCH TRIANGLE PARK, NORTH CAROLINA

    EPA Science Inventory

    Abstract

    The EPA sponsored a workshop held September 29-30, 2003 at the EPA in RTP that was focused on a proposal entitled "A Framework for a Computational Toxicology Research Program in ORD" (www.epa.gov/computox). Computational toxicology is a new research ini...

  1. North East Association for Institutional Research Annual Conference Proceedings (29th, Annapolis, Maryland, November 16-19, 2002).

    ERIC Educational Resources Information Center

    North East Association for Institutional Research.

    This proceedings contains papers from the 2002 annual conference of the Northeast Association for Institutional Research, a meeting devoted to assessment in the 21st century and the challenges that face institutional research. The papers are: (1) "Putting Community College Enrollment Trends in Perspective by the Use of Census Data and Market…

  2. ON-ROAD REMOTE SENSING OF AUTOMOBILE EMISSIONS IN THE RESEARCH TRIANGLE PARK, NORTH CAROLINA AREA: 1997-2001

    EPA Science Inventory

    The report describes automobile exhaust remote sensing data collected by EPA at a number of sites in the Research Triangle Park, NC area during 1997. Data were also collected at one site in Raleigh, NC from 1998 through 2001 for the Coordinating Research Council (CRC) study of re...

  3. Inverse distributed hydrological modelling of alpine catchments

    NASA Astrophysics Data System (ADS)

    Kunstmann, H.; Krause, J.; Mayr, S.

    2005-12-01

    Even in physically based distributed hydrological models, various remaining parameters must be estimated for each sub-catchment. This can involve tremendous effort, especially when the number of sub-catchments is large and the applied hydrological model is computationally expensive. Automatic parameter estimation tools can significantly facilitate the calibration process. Hence, we combined the nonlinear parameter estimation tool PEST with the distributed hydrological model WaSiM. PEST is based on the Gauss-Marquardt-Levenberg method, a gradient-based nonlinear parameter estimation algorithm. WaSiM is a fully distributed hydrological model using physically based algorithms for most of the process descriptions. WaSiM was applied to the alpine/prealpine Ammer River catchment (southern Germany, 710 km2) in a 100×100 m2 horizontal resolution. The catchment is heterogeneous in terms of geology, pedology and land use and shows a complex orography (the difference of elevation is around 1600 m). Using the developed PEST-WaSiM interface, the hydrological model was calibrated by comparing simulated and observed runoff at eight gauges for the hydrologic year 1997 and validated for the hydrologic year 1993. For each sub-catchment four parameters had to be calibrated: the recession constants of direct runoff and interflow, the drainage density, and the hydraulic conductivity of the uppermost aquifer. Additionally, five snowmelt specific parameters were adjusted for the entire catchment. Altogether, 37 parameters had to be calibrated. Additional a priori information (e.g. from flood hydrograph analysis) narrowed the parameter space of the solutions and improved the non-uniqueness of the fitted values. A reasonable quality of fit was achieved. Discrepancies between modelled and observed runoff were also due to the small number of meteorological stations and corresponding interpolation artefacts in the orographically complex terrain. A detailed covariance analysis was performed

  4. Inverse distributed hydrological modelling of Alpine catchments

    NASA Astrophysics Data System (ADS)

    Kunstmann, H.; Krause, J.; Mayr, S.

    2006-06-01

    Even in physically based distributed hydrological models, various remaining parameters must be estimated for each sub-catchment. This can involve tremendous effort, especially when the number of sub-catchments is large and the applied hydrological model is computationally expensive. Automatic parameter estimation tools can significantly facilitate the calibration process. Hence, we combined the nonlinear parameter estimation tool PEST with the distributed hydrological model WaSiM. PEST is based on the Gauss-Marquardt-Levenberg method, a gradient-based nonlinear parameter estimation algorithm. WaSiM is a fully distributed hydrological model using physically based algorithms for most of the process descriptions. WaSiM was applied to the alpine/prealpine Ammer River catchment (southern Germany, 710 km2 in a 100×100 m2 horizontal resolution. The catchment is heterogeneous in terms of geology, pedology and land use and shows a complex orography (the difference of elevation is around 1600 m). Using the developed PEST-WaSiM interface, the hydrological model was calibrated by comparing simulated and observed runoff at eight gauges for the hydrologic year 1997 and validated for the hydrologic year 1993. For each sub-catchment four parameters had to be calibrated: the recession constants of direct runoff and interflow, the drainage density, and the hydraulic conductivity of the uppermost aquifer. Additionally, five snowmelt specific parameters were adjusted for the entire catchment. Altogether, 37 parameters had to be calibrated. Additional a priori information (e.g. from flood hydrograph analysis) narrowed the parameter space of the solutions and improved the non-uniqueness of the fitted values. A reasonable quality of fit was achieved. Discrepancies between modelled and observed runoff were also due to the small number of meteorological stations and corresponding interpolation artefacts in the orographically complex terrain. Application of a 2-dimensional numerical

  5. River runoff and regional climate of a small glaciated catchment area in the Andes in southernmost Patagonia, Chile

    NASA Astrophysics Data System (ADS)

    Schneider, C.; Moritz, M.; Kilian, R.

    2003-04-01

    The river runoff from a small partly glaciated catchment area in southernmost Patagonian Andes in Chile is measured to analyse the influence of regional precipitation and climate dependent glacier ablation on runoff. The first data from March to September 2002 were compared to climate data recorded at an automatic weather station in the area. The poster presents the first detailed hydrometeorological investigation from this part of the Andes. The investigation area is located at 53°S in southernmost South America exactly east of the main divide of the mountain range of the Andes at 72.5°W. The catchment area of about 15 km2 comprises parts of the Gran Campo Nevado Ice Cap reaching up to 1500 m asl, and the outlet glacier Glaciar Lengua which ends at a proglacial lake at 100 m asl. The Gran Campo Nevado Ice Cap is the major ice mass between the Southern Patagonian Ice field in the north and the Strait of Magallan to the South. Climate in the area is characterised by whole-year round cool and super-humid conditions with a mean annual air temperature of 5,6°C at sea level and an annual precipitation sum of approximately 7,000 mm. The Río Lengua itself meets approximately 3.5 km downstreams from the proglacial lake into the fjord system of Canal Garjado which is a branch of Seno Skyring. A continuous hourly record of water levels in the river was obtained from two digital water depth sensors. Runoff was calibrated against river level by measuring runoff at different times with the tracer method of salt dilution and with velocity measurements employing a hydrometric vane. Mean runoff was computed to about 3 m3/s with peak flows exceeding 10 m3/s. Ablation on the glacier was estimated using the degree-day method with a degree-day factor that has been calibrated previously using data from a temporal energy balance weather station on Glacíar Lengua. The correlation between runoff and air temperature and precipitation returned significant correlation coefficients of rt

  6. Establishing a connection between hydrologic model parameters and physical catchment signatures for improved hierarchical Bayesian modeling in ungauged catchments

    NASA Astrophysics Data System (ADS)

    Marshall, L. A.; Weber, K.; Smith, T. J.; Greenwood, M. C.; Sharma, A.

    2012-12-01

    In an effort to improve hydrologic analysis in areas with limited data, hydrologists often seek to link catchments where little to no data collection occurs to catchments that are gauged. Various metrics and methods have been proposed to identify such relationships, in the hope that "surrogate" catchments might provide information for those catchments that are hydrologically similar. In this study we present a statistical analysis of over 150 catchments located in southeast Australia to examine the relationship between a hydrological model and certain catchment metrics. A conceptual rainfall-runoff model is optimized for each of the catchments and hierarchical clustering is performed to link catchments based on their calibrated model parameters. Clustering has been used in recent hydrologic studies but catchments are often clustered based on physical characteristics alone. Usually there is little evidence to suggest that such "surrogate" data approaches provide sufficiently similar model predictions. Beginning with model parameters and working backwards, we hope to establish if there is a relationship between the model parameters and physical characteristics for improved model predictions in the ungauged catchment. To analyze relationships, permutational multivariate analysis of variance tests are used that suggest which hydrologic metrics are most appropriate for discriminating between calibrated catchment clusters. Additional analysis is performed to determine which cluster pairs show significant differences for various metrics. We further examine the extent to which these results may be insightful for a hierarchical Bayesian modeling approach that is aimed at generating model predictions at an ungauged site. The method, known as Bayes Empirical Bayes (BEB) works to pool information from similar catchments to generate informed probability distributions for each model parameter at a data-limited catchment of interest. We demonstrate the effect of selecting

  7. The Computable Catchment: An executable document for model-data software sharing, reproducibility and interactive visualization

    NASA Astrophysics Data System (ADS)

    Gil, Y.; Duffy, C.

    2015-12-01

    This paper proposes the concept of a "Computable Catchment" which is used to develop a collaborative platform for watershed modeling and data analysis. The object of the research is a sharable, executable document similar to a pdf, but one that includes documentation of the underlying theoretical concepts, interactive computational/numerical resources, linkage to essential data repositories and the ability for interactive model-data visualization and analysis. The executable document for each catchment is stored in the cloud with automatic provisioning and a unique identifier allowing collaborative model and data enhancements for historical hydroclimatic reconstruction and/or future landuse or climate change scenarios to be easily reconstructed or extended. The Computable Catchment adopts metadata standards for naming all variables in the model and the data. The a-priori or initial data is derived from national data sources for soils, hydrogeology, climate, and land cover available from the www.hydroterre.psu.edu data service (Leonard and Duffy, 2015). The executable document is based on Wolfram CDF or Computable Document Format with an interactive open-source reader accessible by any modern computing platform. The CDF file and contents can be uploaded to a website or simply shared as a normal document maintaining all interactive features of the model and data. The Computable Catchment concept represents one application for Geoscience Papers of the Future representing an extensible document that combines theory, models, data and analysis that are digitally shared, documented and reused among research collaborators, students, educators and decision makers.

  8. Monitoring of fluvial transport in small upland catchments - methods and preliminary results

    NASA Astrophysics Data System (ADS)

    Janicki, Grzegorz; Rodzik, Jan; Chabudziński, Łukasz; Franczak, Łukasz; Siłuch, Marcin; Stępniewski, Krzysztof; Dyer, Jamie L.; Kołodziej, Grzegorz; Maciejewska, Ewa

    2014-06-01

    In April 2011 a study was initiated, financed from resources of the Polish National Science Centre, entitled: ‘Rainstorm prediction and mathematic modelling of their environmental and social-economical effects’ (No. NN/306571640). The study, implemented by a Polish-American team, covers meteorological research, including: (1) monitoring of single cell storms developing in various synoptic situations, (2) detection of their movement courses, and (3) estimation of parameters of their rain field. Empirical studies, including hydrological and geomorphological measurements, are conducted in objects researched thoroughly in physiographic terms (experimental catchments) in the Lublin region (SE Poland), distinguished by high frequency of occurrence of the events described. For comparative purposes, studies are also carried out on selected model areas in the lower course of the Mississippi River valley (USA), in a region with high frequency of summer rainstorms. For detailed studies on sediment transport processes during rainstorm events, catchments of low hydrological rank and their sub-catchments in a cascade system were selected. For the basic, relatively uniform geomorpho logical units distinguished this way, erosion and deposition balance of material transported was determined. The aim of work was to determine influence of weather condition on fluvial transport rate in small catchment with low hydrological order

  9. Nonstationarities in Catchment Response According to Basin and Rainfall Characteristics: Application to Korean Watershed

    NASA Astrophysics Data System (ADS)

    Kwon, Hyun-Han; Kim, Jin-Guk; Jung, Il-Won

    2015-04-01

    It must be acknowledged that application of rainfall-runoff models to simulate rainfall-runoff processes are successful in gauged watershed. However, there still remain some issues that will need to be further discussed. In particular, the quantitive representation of nonstationarity issue in basin response (e.g. concentration time, storage coefficient and roughness) along with ungauged watershed needs to be studied. In this regard, this study aims to investigate nonstationarity in basin response so as to potentially provide useful information in simulating runoff processes in ungauged watershed. For this purpose, HEC-1 rainfall-runoff model was mainly utilized. In addition, this study combined HEC-1 model with Bayesian statistical model to estimate uncertainty of the parameters which is called Bayesian HEC-1 (BHEC-1). The proposed rainfall-runofall model is applied to various catchments along with various rainfall patterns to understand nonstationarities in catchment response. Further discussion about the nonstationarity in catchment response and possible regionalization of the parameters for ungauged watershed are discussed. KEYWORDS: Nonstationary, Catchment response, Uncertainty, Bayesian Acknowledgement This research was supported by a Grant (13SCIPA01) from Smart Civil Infrastructure Research Program funded by the Ministry of Land, Infrastructure and Transport (MOLIT) of Korea government and the Korea Agency for Infrastructure Technology Advancement (KAIA).

  10. Catchments as simple dynamical systems: A case study on methods and data requirements for parameter identification

    NASA Astrophysics Data System (ADS)

    Melsen, Lieke; Teuling, Adriaan; van Berkum, Sonja; Torfs, Paul; Uijlenhoet, Remko

    2014-05-01

    In many rainfall-runoff models at least some calibration of model parameters has to take place. Especially for ungauged or poorly gauged basins this can be problematic, because there is little or no data available for calibration. A possible solution to overcome the problems caused by data scarcity is to set up a measurement campaign for a short time period. With the employed approach based on the theory of Kirchner (2009), a model was developed and applied to the Rietholzbach catchment in Switzerland (Teuling et al., 2010, Seneviratne et al., 2012), with only two parameters. These two parameters describe a unique storage-discharge relation. The model is constructed such that the parameters can be determined not only with automatic calibration, but also by recession analysis and a priori from Boussinesq theory. The automatic calibration and the recession analysis have been fed with different selections of the full data record as well as with the full data record itself. For Boussinesq theory, catchment characteristics were given as required input. In the end, a comparison of the performance of the three different methods was made, and a comparison on the amount of data that is required by each of the three parameter identification methods. Melsen, L.A., Teuling, A.J., van Berkum, S.W., Torfs, P.J.J.F., Uijlenhoet, R. (2013) Catchments as simple dynamical systems: A case study on methods and data requirements for parameter identification, Water Resour. Res., under review References Kirchner, J.W. (2009), Catchments as simple dynamical systems: Catchment characterization, rainfall-runoff modeling, and doing hydrology backward, Water Resour. Res. 45:W02429. Seneviratne, S.I., I. Lehner, J. Gurtz, A.J. Teuling, H Lang, U. Moser, D. Grebner, L. Menzel, K. Schro, T. Vitvar, and M. Zappa (2012), Swiss prealpine Rietholzbach research catchment and lysimeter: 32 year time series and 2003 drought event, Water Resour. Res. 48:W06526. Teuling, A. J., I. Lehner, J. W. Kirchner

  11. New understanding of the complexity of groundwater flow in Chalk catchments of the UK

    NASA Astrophysics Data System (ADS)

    Peach, D.; Shand, P.; Gooddy, D.; Abesser, C.; Bloomfield, J.; Mathias, S.; Butler, A.; Williams, A.; Binley, A.; Wheater, H.

    2006-12-01

    The Chalk is the largest aquifer in the UK accounting for more than half the groundwater used and nearly a quarter of the total public water supplied in England and Wales. Although the Chalk is a double porosity and permeability medium, transmission of water in the saturated zone depends largely on flow through fractures, the location and distribution of which are controlled by lithology and geological structure. These features operate on a number of spatial scales and so provide a range of flow pathways that can markedly affect both stream flow and water quality. In addition, overlying Palaeogene or superficial deposits can act as controls on recharge and zones of increased groundwater storage. As part of a major initiative on Lowland Catchment Research in the UK two Chalk sub-catchments, in the River Thames basin, the rivers Pang and Lambourn, have been the focus of an intensive set of studies. The catchments have been characterised using a multidisciplinary approach. This has resulted in an improved understanding of the way such catchments work and the mechanisms that control groundwater flow. The low fracture porosity gives rise to a low specific yield, which means that large fluctuations in water table elevation beneath the interfluves are not uncommon. Consequently, groundwater catchments differ from the topographic catchments and their size varies seasonally. This means, for example, that groundwater might be flowing to the River Pang in winter but to the River Thames in summer. It also means that various flow features in the catchment may be active at different locations and times during the year. Four flow systems have been identified, through a detailed analysis of the data; a shallow, but rapid flow system; a slower, deeper system; a very high velocity system developed in large diameter solution enhanced fractures and a system found in the river valley sediments. The interconnections between and within these systems can be poor and sometimes vary on a

  12. Spatial and temporal variation of residence time and storage volume of subsurface water evaluated by multi-tracers approach in mountainous headwater catchments

    NASA Astrophysics Data System (ADS)

    Tsujimura, Maki; Yano, Shinjiro; Abe, Yutaka; Matsumoto, Takehiro; Yoshizawa, Ayumi; Watanabe, Ysuhito; Ikeda, Koichi

    2015-04-01

    Headwater catchments in mountainous region are the most important recharge area for surface and subsurface waters, additionally time and stock information of the water is principal to understand hydrological processes in the catchments. However, there have been few researches to evaluate variation of residence time and storage volume of subsurface water in time and space at the mountainous headwaters especially with steep slope. We performed an investigation on age dating and estimation of storage volume using simple water budget model in subsurface water with tracing of hydrological flow processes in mountainous catchments underlain by granite, Paleozoic and Tertiary, Yamanashi and Tsukuba, central Japan. We conducted hydrometric measurements and sampling of spring, stream and ground waters in high-flow and low-flow seasons from 2008 through 2012 in the catchments, and CFCs, stable isotopic ratios of oxygen-18 and deuterium, inorganic solute constituent concentrations were determined on all water samples. Residence time of subsurface water ranged from 11 to 60 years in the granite catchments, from 17 to 32 years in the Paleozoic catchments, from 13 to 26 years in the Tertiary catchments, and showed a younger age during the high-flow season, whereas it showed an older age in the low-flow season. Storage volume of subsurface water was estimated to be ranging from 10 ^ 4 to 10 ^ 6 m3 in the granite catchments, from 10 ^ 5 to 10 ^ 7 m3 in the Paleozoic catchments, from 10 ^ 4 to 10 ^ 6 m3 in the Tertiary catchments. In addition, seasonal change of storage volume in the granite catchments was the highest as compared with those of the Paleozoic and the Tertiary catchments. The results suggest that dynamic change of hydrological process seems to cause a larger variation of the residence time and storage volume of subsurface water in time and space in the granite catchments, whereas higher groundwater recharge rate due to frequent fissures or cracks seems to cause larger

  13. Highlighting the Impacts of North-South Research Collaboration among Canadian and Southern Higher Education Partners (Principaux impacts des collaborations de recherche Nord-Sud entre les partenaires des etablissements d'enseignement superieur du Canada et du Sud)

    ERIC Educational Resources Information Center

    Association of Universities and Colleges of Canada, 2006

    2006-01-01

    The Association of Universities and Colleges of Canada (AUCC) felt it was timely to create an academic forum in which university researchers have the opportunity to engage with their peers and relevant stakeholders and document the impacts of their North-South research collaboration in a peer-reviewed publication. The Association achieved this by…

  14. Making a World of Difference. Dimension: Language '91. Selected Papers from the Joint Meeting of the Southern Conference on Language Teaching and the Foreign Language Association of North Carolina (Research Triangle Park, North Carolina, 1991).

    ERIC Educational Resources Information Center

    Terry, Robert M., Ed.

    Papers from the 1991 joint Southern Conference on Language Teaching (SCOLT)/ Foreign Language Association of North Carolina (FLANC) conference are presented. Because the state of North Carolina is in the forefront of state-mandated foreign language education in the elementary schools (FLES), 4 of the 10 articles in this volume address FLES…

  15. Dynamics of large wood during a flash flood in two mountain catchments

    NASA Astrophysics Data System (ADS)

    Lucía, A.; Comiti, F.; Borga, M.; Cavalli, M.; Marchi, L.

    2015-02-01

    Understanding and modelling the dynamics of large wood (LW) in rivers during flood events has spurred a great deal of research in recent years. However, few studies have documented the effect of high-magnitude flash floods on LW recruitment, transport and deposition. On 25 October 2011, the Magra river basin (north-western Italy) was hit by an intense rainstorm, with hourly rainfall rates up to 130 mm h-1 and event rain accumulations up to 540 mm in 8 h. Such large rainfall intensities originated flash floods in the main river channels and in several tributaries, causing severe damages and loss of lives. Numerous bridges were partly or fully clogged by LW jams. A post-flood survey was carried out along the channels of two catchments that were severely and similarly affected by this event, the Gravegnola (34.6 km2) and Pogliaschina (25.1 km2). The analysis highlighted a very relevant channel widening in many channel reaches, which was more marked in the Gravegnola basin. Large wood recruitment rates were very high, up to 1270 m3 km-1, and most of it (70-80%) was eroded from the floodplains as a consequence of channel widening processes, while the rest came from hillslopes processes. Overall, drainage area and channel slope are the most relevant controlling variables in explaining the reach-scale variability of LW recruitment, whereas LW deposition appears to be more complex, as correlation analysis did not evidence any statistically significant relationship with the tested controlling variables. Indeed, in-channel LW displacement during the flood has been mostly limited by the presence of bridges, given the relatively large width attained by channels after the event.

  16. Dynamics of large wood during a flash flood in two mountain catchments

    NASA Astrophysics Data System (ADS)

    Lucía, A.; Comiti, F.; Borga, M.; Cavalli, M.; Marchi, L.

    2015-08-01

    Understanding and modelling the dynamics of large wood (LW) in rivers during flood events has spurred a great deal of research in recent years. However, few studies have documented the effect of high-magnitude flash floods on LW recruitment, transport and deposition. On 25 October 2011, the Magra river basin (north-western Italy) was hit by an intense rainstorm, with hourly rainfall rates up to 130 mm h-1 and event rain accumulations up to 540 mm in 8 h. Such large rainfall intensities originated flash floods in the main river channels and in several tributaries, causing severe damages and loss of lives. Numerous bridges were partly or fully clogged by LW jams. A post-flood survey was carried out along the channels of two catchments that were severely and similarly affected by this event, the Gravegnola (34.3 km2) and Pogliaschina (25.1 km2). The analysis highlighted a very relevant channel widening in many channel reaches, which was more marked in the Gravegnola basin due to highly erodible material forming the slopes adjacent to the fluvial corridor. Large wood recruitment rates were very high, up to 1270 m3 km-1, and most of it (70-80 %) was eroded from the floodplains as a consequence of channel-widening processes, while the rest came from hillslopes processes. Overall, drainage area and channel slope are the most relevant controlling variables in explaining the reach-scale variability of LW recruitment, whereas LW deposition appears to be more complex, as correlation analysis did not evidence any statistically significant relationship with the tested controlling variables. Indeed, in-channel LW displacement during the flood has been mostly limited by the presence of bridges, given the relatively large width attained by channels after the event.

  17. Co-evolution of volcanic catchments in Japan

    NASA Astrophysics Data System (ADS)

    Yoshida, T.; Troch, P. A. A.

    2015-12-01

    Present day landscapes have evolved over time through interactions between the prevailing climates and geological settings. Understanding the linkage between spatial patterns of landforms, soils, and vegetation in landscapes and their hydrological response is critical to make quantitative predictions in ungaged basins. Catchment co-evolution is a theoretical framework that seeks to formulate hypotheses about the mechanisms and conditions that determine the historical development of catchments and how such evolution affects their hydrological response. In this study, we selected 14 volcanic catchments of different ages (from 0.22 to 82Ma) in Japan. We derived indices of landscape properties (drainage density) as well as hydrological response (annual water balance, baseow index, and flow duration curves) and examined their relation with catchment age and climate (through the aridity index). We found signicant correlation between drainage density and baseow index with age, but not with climate. The age of the catchments was also signicantly related to intra-annual flow variability. Younger catchments tend to have lower peak flows and higher low flows, while older catchments exhibit more flashy runoff. The decrease of baseflow with catchment age confirms previous studies that hypothesized that in volcanic landscapes the major flow pathways have changed over time, from deep groundwater flow to shallow subsurface flow. The drainage density of our catchments decreased with age, contrary to previous findings in similar volcanic catchments but of signicant younger age than the ones explored here. In these younger catchments, an increase in drainage density with age was observed, and it was hypothesized that this was because of more landscape incision due to increasing near-surface lateral flow paths in more mature catchments. Our results suggest that as catchments further evolve, hydrologically active channels retreat as less recharge leads to lower average aquifer levels

  18. Catchment Engineering: A New Paradigm in Water Management

    NASA Astrophysics Data System (ADS)

    Quinn, P. F.; Burke, S.; O'Donnell, G. M.; Wilkinson, M.; Jonczyk, J.; Barber, N.; Nicholson, A.; Proactive Team

    2011-12-01

    Recent catchment initiatives have highlighted the need for new holistic approaches to sustainable water management. Here, a catchment engineering approach seeks to describe catchment 'function' (or role) as the principal driver for evaluating how it should be managed in the future. Catchment engineering does not seek to re-establish a natural system but seeks to work with natural processes in order to engineer landscapes so that multiple benefits accrue. This approach involves quantifying and assessing catchment change and impacts but most importantly suggests an urgent and proactive agenda for future planning. In particular, an interventionist approach to managing hydrological flow pathways across scale is proposed. It is already accepted that future management will require a range of scientific expertise and full engagement with stakeholders, namely the general public and policy makers. This inclusive concept under a catchment engineering agenda forces any consortia to commit to actively changing and perturbing the catchment system and thus learn, in situ, how to manage the environment for collective benefits. The shared cost, the design, the implementation, the evaluation and any subsequent modifications should involve all relevant parties in the consortia. This joint ownership of a 'hands on' interventionist agenda to catchment change is at the core of catchment engineering. In this paper we show a range of catchment engineering projects from the UK that have addressed multi-disciplinary approaches to flooding, pollution and ecosystem management whilst maintaining economic food production. Local scale demonstration activities, led by local champions, have proven to be an effective means of encouraging wider uptake. Catchment engineering is a concept that relies on all relevant parties within a catchment to take responsibility for the water quantity and quality that arises from the catchment. Further, any holistic solution requires a bottom up, problem solving

  19. The Center for Aerospace Research: A NASA Center of Excellence at North Carolina Agricultural and Technical State University

    NASA Technical Reports Server (NTRS)

    Lai, Steven H.-Y.

    1992-01-01

    This report documents the efforts and outcomes of our research and educational programs at NASA-CORE in NCA&TSU. The goal of the center was to establish a quality aerospace research base and to develop an educational program to increase the participation of minority faculty and students in the areas of aerospace engineering. The major accomplishments of this center in the first year are summarized in terms of three different areas, namely, the center's research programs area, the center's educational programs area, and the center's management area. In the center's research programs area, we focus on developing capabilities needed to support the development of the aerospace plane and high speed civil transportation system technologies. In the educational programs area, we developed an aerospace engineering option program ready for university approval.

  20. Dynamic processes in the mountain catchment

    NASA Astrophysics Data System (ADS)

    Trifonova, Tatiana; Arakelian, Sergei

    2015-04-01

    The process of the river cftchment foundation and the mechanisms being in the basis of its development are not clear at present. Principal phenomena determining the dynamics of formation of the river catchment are under our study in this paper for the case of the mountain basin as an example. The methodology of this monitoring includes the space image recognition and computer data processing of the images for the Maliy Caucasus Mountains. Mountain river catchment formation on the slope of the ridge can be considered as a self-organizing staged process of its evolution passing through several non-equilibrium but steady-state conditions. We consider a system of tributaries in the mountain river catchment as a system of cracks, which are formed on the slope of the mountain massif. In other words, the formation of river networks should be the result of development of several processes, among of which the mechanisms of crack development should play a dominant role. The principal results, discussed in the present report, can be formulated as follow. (1) The mountain catchment (litho-watershed) formation takes place under conditions of the confined states of a mountain massif: on the one hand it is bounded by the surface of the slope; but on the other hand, - by a primary cracks density occurrence (as a spatial distribution 3D-crack net). (2) The development in time of the river catchment takes place by several stages. Each stage specifies a definite energetic state of the system in the mountain massif. (3) The overhead river streams arise not only due to surface water, but and namely due to rising of water from underground water horizons over the watercourse cracks penetrating deeply into the underground. (4) The 3D-river catchment structure results in concept in behavior of the unit as an open nonlinear dynamic system with a spatially distributed feedback. The energetic (endogen) processes of formation, rising and bifurcation for cracks are the consequence of relaxation

  1. The hydrological response of a small catchment after the abandonment of terrace cultivation. A study case in northwestern Spain

    NASA Astrophysics Data System (ADS)

    Llorente-Adán, Jose A.; Lana-Renault, Noemí; Galilea, Ianire; Ruiz-Flaño, Purificacion

    2015-04-01

    Terrace construction for cultivation results in a complete transformation of the hillslopes to a series of flat sectors and almost vertical steps. This strategy, which involves a redistribution of soils and a re-organization of the drainage network, provides fertile soil over steep slopes, improves infiltration and controls overland flow under conditions of intense rainstorms. In Camero Viejo (north-western Iberian ranges) most of the hillslopes are occupied by terraced fields. During the XXth century, rural population declined and agricultural practices were abandoned. In this area, a small catchment (1.9 km2) was monitored in 2012 for studying how the abandonment of agricultural terraces affect water and sediment transfer from the hillslopes to the channels. Terraces occupy 40% of the catchment and are covered by sparse grass and shrubs. The equipment installed in the catchment registers continuously meteorological data, discharge and water table fluctuations. Data on suspended sediment transport is obtained by means of a rising-stage sampler. Here we present the hydrological results corresponding to the years 2012-13 and 2013-14. The hydrological response of the catchment was moderate (annual runoff coefficient < 0.20), which could be in part explained by the high evapotranspiration rates reported in the area. Lows flows were recorded in summer and autumn, when the water reserves of the catchment were dry, and high flows occurred from January, when the catchment became wetter. The shape of the hydrographs, with slow response times, moderate peakflows and long recession limbs suggested a large contribution of subsurface flow, probably favored by deep and well structured soils in the bench terraces. Soil saturation areas were not observed during the study period, suggesting that soil infiltration processes and subsurface flow are important, and that the drainage system of the terraces is probably well maintained. No suspended sediment has been collected so far

  2. Effects of model input data uncertainty in simulating water resources of a transnational catchment

    NASA Astrophysics Data System (ADS)

    Camargos, Carla; Breuer, Lutz

    2016-04-01

    Landscape consists of different ecosystem components and how these components affect water quantity and quality need to be understood. We start from the assumption that water resources are generated in landscapes and that rural land use (particular agriculture) has a strong impact on water resources that are used downstream for domestic and industrial supply. Partly located in the north of Luxembourg and partly in the southeast of Belgium, the Haute-Sûre catchment is about 943 km2. As part of the catchment, the Haute-Sûre Lake is an important source of drinking water for Luxembourg population, satisfying 30% of the city's demand. The objective of this study is investigate impact of spatial input data uncertainty on water resources simulations for the Haute-Sûre catchment. We apply the SWAT model for the period 2006 to 2012 and use a variety of digital information on soils, elevation and land uses with various spatial resolutions. Several objective functions are being evaluated and we consider resulting parameter uncertainty to quantify an important part of the global uncertainty in model simulations.

  3. Institutional Research: Leadership through Excellence. North East Association for Institutional Research Annual Conference Proceedings (28th, Cambridge, Massachusetts, November 17-20, 2001).

    ERIC Educational Resources Information Center

    North East Association for Institutional Research.

    The theme of the 2001 annual conference of the Northeast Association for Institutional Research was Institutional Research: Leadership through Excellence. These proceedings represent the intellectual content and insights shared during the conference. The papers are: (1) The Rocky Road to Graduation: An Academic Career Flow Model for Tracking…

  4. Groundwater recharge from point to catchment scale

    NASA Astrophysics Data System (ADS)

    Leterme, Bertrand; Di Ciacca, Antoine; Laloy, Eric; Jacques, Diederik

    2016-04-01

    Accurate estimation of groundwater recharge is a challenging task as only a few devices (if any) can measure it directly. In this study, we discuss how groundwater recharge can be calculated at different temporal and spatial scales in the Kleine Nete catchment (Belgium). A small monitoring network is being installed, that is aimed to monitor the changes in dominant processes and to address data availability as one goes from the point to the catchment scale. At the point scale, groundwater recharge is estimated using inversion of soil moisture and/or water potential data and stable isotope concentrations (Koeniger et al. 2015). At the plot scale, it is proposed to monitor the discharge of a small drainage ditch in order to calculate the field groundwater recharge. Electrical conductivity measurements are necessary to separate shallow from deeper groundwater contribution to the ditch discharge (see Di Ciacca et al. poster in session HS8.3.4). At this scale, two or three-dimensional process-based vadose zone models will be used to model subsurface flow. At the catchment scale though, using a mechanistic, process-based model to estimate groundwater recharge is debatable (because of, e.g., the presence of numerous drainage ditches, mixed land use pixels, etc.). We therefore investigate to which extent various types of surrogate models can be used to make the necessary upscaling from the plot scale to the scale of the whole Kleine Nete catchment. Ref. Koeniger P, Gaj M, Beyer M, Himmelsbach T (2015) Review on soil water isotope based groundwater recharge estimations. Hydrological Processes, DOI: 10.1002/hyp.10775

  5. Creating a catchment perspective for river restoration

    NASA Astrophysics Data System (ADS)

    Benda, L.; Miller, D.; Barquín, J.

    2011-03-01

    One of the major challenges in river restoration is to identify the natural fluvial landscape in catchments with a long history of river control. Intensive land use on valley floors often predates the earliest remote sensing: levees, dikes, dams, and other structures alter valley-floor morphology, river channels and flow regimes. Consequently, morphological patterns indicative of the fluvial landscape including multiple channels, extensive floodplains, wetlands, and fluvial-riparian and tributary-confluence dynamics can be obscured, and information to develop appropriate and cost effective river restoration strategies can be unavailable. This is the case in the Pas River catchment in northern Spain (650 km2), in which land use and development have obscured the natural fluvial landscape in many parts of the basin. To address this issue we coupled general principles of hydro-geomorphic processes with computer tools to characterize the fluvial landscape. Using a 5-m digital elevation model, valley-floor surfaces were mapped according to elevation above the channel and proximity to key geomorphic processes. The predicted fluvial landscape is patchily distributed according to topography, valley morphology, river network structure, and fan and terrace landforms. The vast majority of the fluvial landscape in the main segments of the Pas River catchment is presently masked by human infrastructure, with only 15% not impacted by river control structures and development. The reconstructed fluvial landscape provides a catchment scale context to support restoration planning, in which areas of potential ecological productivity and diversity could be targeted for in-channel, floodplain and riparian restoration projects.

  6. Can spatial study of hydrological connectivity explain some behaviors of catchments?

    NASA Astrophysics Data System (ADS)

    Cantreul, Vincent

    2015-04-01

    Erosion is a major threat to European soil. Consequences can be very important both on-site and off-site. Belgian loamy soils are highly vulnerable to this threat because of their natural sensitivity to erosion on the one hand, and because the land is mainly used for intensive agricultural practices on the other hand. Over the last few decades, rising erosion has even been observed in our regions. This shows the importance of a deeper understanding of the coupled phenomena of runoff and erosion in order to manage soils at catchment scale. Plenty of research have already studied this but all agree to say that it seems to have a non-linear relationship between rainfall and discharge, as well as between rainfall and erosion. For that reason, a new concept has been developed a few years ago: the hydrological connectivity. Several research have focused on connectivity but up to now, each there are as much definition as papers. In this thesis, it will be important firstly to resume all these definitions to clarify this concept. Secondly, a methodology using various transects on the watershed and some pertinent field measurements will be used. These measurements include spatial distribution of particle size, surface states and soil moisture. A new approach of photogrammetry using an UAV will be used to observe erosion and deposition zones on the watershed. In this framework, several time scales will be studied from the event scale to the annual scale passing by monthly and seasonal scales. All this will serve to progress toward a better understanding of the concept of hydrological connectivity in order to study erosion at catchment scale. The final goal of this study is to describe hydrologically each different part of the catchment and to generalize these behaviors to other catchments with similar properties if possible. Afterwards, this research will be integrated in an existing (or not) model to improve the modelling of discharge and erosion in the catchment. Thanks to

  7. Similarity and scale in catchment storm response

    NASA Technical Reports Server (NTRS)

    Wood, Eric F.; Sivapalan, Murugesu; Beven, Keith

    1993-01-01

    Until recently, very little progress had been made in understanding the relationship between small-scale variability of topography, soil, and rainfalls and the storm response seen at the catchment scale. The work reviewed here represents the first attempt at a systematic theoretical framework for such understanding in the context of surface runoff generation by different processes. The parameterization of hydrological processes over a range of scales is examined, and the concept of the 'representative elementary area' (REA) is introduced. The REA is a fundamental scale for catchment modeling at which continuum assumptions can be applied for the spatially variable controls and parameters, and spatial patterns no longer have to be considered explicitly. The investigation of scale leads into the concept of hydrologic similarity in which the effects of the environmental controls on runoff generation and flood frequency response be investigated independently of catchment scale. The paper reviews the authors' initial results and hopefully will motivate others to also investigate the issues of hydrologic scale and similarity.

  8. Modeling of facade leaching in urban catchments

    NASA Astrophysics Data System (ADS)

    Coutu, S.; Del Giudice, D.; Rossi, L.; Barry, D. A.

    2012-12-01

    Building facades are protected from microbial attack by incorporation of biocides within them. Flow over facades leaches these biocides and transports them to the urban environment. A parsimonious water quantity/quality model applicable for engineered urban watersheds was developed to compute biocide release from facades and their transport at the urban basin scale. The model couples two lumped submodels applicable at the basin scale, and a local model of biocide leaching at the facade scale. For the facade leaching, an existing model applicable at the individual wall scale was utilized. The two lumped models describe urban hydrodynamics and leachate transport. The integrated model allows prediction of biocide concentrations in urban rivers. It was applied to a 15 km2urban hydrosystem in western Switzerland, the Vuachère river basin, to study three facade biocides (terbutryn, carbendazim, diuron). The water quality simulated by the model matched well most of the pollutographs at the outlet of the Vuachère watershed. The model was then used to estimate possible ecotoxicological impacts of facade leachates. To this end, exceedance probabilities and cumulative pollutant loads from the catchment were estimated. Results showed that the considered biocides rarely exceeded the relevant predicted no-effect concentrations for the riverine system. Despite the heterogeneities and complexity of (engineered) urban catchments, the model application demonstrated that a computationally "light" model can be employed to simulate the hydrograph and pollutograph response within them. It thus allows catchment-scale assessment of the potential ecotoxicological impact of biocides on receiving waters.

  9. Climate change influence on catchment sediment yield

    NASA Astrophysics Data System (ADS)

    Rulli, Maria Cristina; Grossi, Giovanna

    2010-05-01

    The effects of a change in climate are expected to be recognizable in many environmental aspects even at small spatial scales: atmospheric carbon dioxide concentration, air temperature, precipitation pattern (days of snowfall translate in days of rainfall), rainfall intensity and erosivity. As a consequence, strong modifications may affect the rate of evapo-transpiration, infiltration and plant biomass production, but also of the soil erosion. To which extent climate change may affect runoff production, soil erosion and sediment transport in upland catchments is investigated here by combining data of long term precipitation, sediment yield and future climate change provided by Global Circulation Models (GCMs) with a spatially distributed modeling approach to flow generation and surface erosion. The model accounts for changes in the structure and properties of soil and vegetation cover by combining the tube-flux approach to the topographic watershed partitioning through a parsimonious parametrization of the main hydrological processes. This model is used to predict hydrological and sediment fluxes for three small catchments in Saint Gabriel mountains of Southern California under control and climate change conditions. Simulation runs using a 45 years long record of hourly precipitation, both observed and referred to a future scenario, show that climate change may induce a significant modification in the catchment response to storms, with major effects on erosion and flood flows.

  10. North-South benefit sharing arrangements in bioprospecting and genetic research: a critical ethical and legal analysis.

    PubMed

    Schüklenk, Udo; Kleinsmidt, Anita

    2006-12-01

    Most pharmaceutical research carried out today is focused on the treatment and management of the lifestyle diseases of the developed world. Diseases that affect mainly poor people are neglected in research advancements in treatment because they cannot generate large financial returns on research and development costs. Benefit sharing arrangements for the use of indigenous resources and genetic research could only marginally address this gap in research and development in diseases that affect the poor. Benefit sharing as a strategy is conceptually problematic, even if one, as we do, agrees that impoverished indigenous communities should not be exploited and that they should be assisted in improving their living conditions. The accepted concept of intellectual property protection envisages clearly defined originators and owners of knowledge, whereas the concept of community membership is fluid and indigenous knowledge is, by its very nature, open, with the originator(s) lost in the mists of time. The delineation of 'community' presents serious conceptual and practical difficulties as few communities form discrete, easily discernable groups, and most have problematic leadership structures. Benefit sharing is no substitute for governments' responsibility to uplift impoverished communities. Benefit sharing arrangements may be fraught with difficulties but considerations of respect and equity demand that prior informed consent and consultation around commercialisation of knowledge take place with the source community and their government. PMID:17038004

  11. Water ponding and catchment runoff as influenced by conservation agriculture in May Zeg-zeg (Ethiopia)

    NASA Astrophysics Data System (ADS)

    Lanckriet, Sil; Nyssen, Jan; Araya, Tesfay; Poesen, Jean; Govaerts, Bram; Bauer, Hans; Deckers, Jozef; Haile, Mitiku; Verfaillie, Els; Cornelis, Wim M.

    2013-04-01

    This study evaluates the practice of conservation agriculture (CA) in the May Zeg-zeg catchment (MZZ; 187 ha) in the North Ethiopian Highlands as a soil management technique for reducing soil loss and runoff, and assesses the consequences of future large-scale implementation on soil and hydrology at catchment-level. The study of such practice is important especially under conditions of climate change, since EdGCM (Educational Global Climate Model) simulation predicts by 2040 an increase in precipitation by more than 100 mm yr-1 in the study area. Firstly, field-saturated infiltration rates, together with soil texture and soil organic carbon contents, were measured. Relation with local topography allows to generate a pedotransfer function for field-saturated infiltration rate, and spatial interpolation with Linear Regression Mapping was used to map field-saturated infiltration rates optimally within the catchment. Secondly, on several farmlands, CA was checked against Plain Tillage (PT) for values of field-saturated infiltration rates, soil organic carbon, runoff and soil loss. Results show no significant differences for infiltration rates but significant differences for runoff and soil loss (as measured in the period 2005-2011). Runoff coefficients were 30.4% for PT and 18.8% for CA; soil losses were 35.4 t ha-1 yr-1 for PT and 14.4 t ha-1 yr-1 for CA. Thirdly, all collected information was used to predict future catchment hydrological response for full-implementation of CA under the predicted wetter climate (simulation with EdGCM). Curve Numbers for farmlands with CA were calculated. An area-weighted Curve Number allows the simulation of the 2011 rainy season runoff, predicting a total runoff depth of 23.5 mm under CA and 27.9 mm under PT. Furthermore, the Revised Universal Soil Loss Equation management factor P was calibrated for CA. Results also show the important influence of increased surface roughness on water ponding, modeled with a hydrologic conservation

  12. High-frequency nutrient monitoring to infer seasonal patterns in catchment source availability, mobilisation and delivery.

    PubMed

    Bende-Michl, Ulrike; Verburg, Kirsten; Cresswell, Hamish P

    2013-11-01

    To explore the value of high-frequency monitoring to characterise and explain riverine nutrient concentration dynamics, total phosphorus (TP), reactive phosphorus (RP), ammonium (NH4-N) and nitrate (NO3-N) concentrations were measured hourly over a 2-year period in the Duck River, in north-western Tasmania, Australia, draining a 369-km(2) mixed land use catchment area. River discharge was observed at the same location and frequency, spanning a wide range of hydrological conditions. Nutrient concentrations changed rapidly and were higher than previously observed. Maximum nutrient concentrations were 2,577 μg L(-1) TP, 1,572 μg L(-1) RP, 972 μg L(-1) NH₄-N and 1,983 μg L(-1) NO₃-N, respectively. Different nutrient response patterns were evident at seasonal, individual event and diurnal time scales-patterns that had gone largely undetected in previous less frequent water quality sampling. Interpretation of these patterns in terms of nutrient source availability, mobilisation and delivery to the stream allowed the development of a conceptual model of catchment nutrient dynamics. Functional stages of nutrient release were identified for the Duck River catchment and were supported by a cluster analysis which confirmed the similarities and differences in nutrient responses caused by the sequence of hydrologic events: (1) a build-up of nutrients during periods with low hydrologic activity, (2) flushing of readily available nutrient sources at the onset of the high flow period, followed by (3) a switch from transport to supply limitation, (4) the accessibility of new nutrient sources with increasing catchment wetness and hydrologic connectivity and (5) high nutrient spikes occurring when new sources become available that are easily mobilised with quickly re-established hydrologic connectivity. Diurnal variations that could be influenced by riverine processes and/or localised point sources were also identified as part of stage (1) and during late recession of some of

  13. The role of groundwater in streamflow in a headwater catchment with sub-humid climate

    NASA Astrophysics Data System (ADS)

    Liu, Yaping; Tian, Fuqiang; Hu, Hongchang; Tie, Qiang

    2015-04-01

    Recent studies have suggested that bedrock groundwater can exert considerable influence on streamflow in headwater catchments under humid climate. However, study of the role of bedrock groundwater is still challenged due to limited direct observation data. In this study, by utilizing observed hydrometric and hydrochemical data, we aimed at characterize the bedrock groundwater's response to rainfall at hillslope and catchment scales in a small headwater catchment with sub-humid climate. We selected Xitaizi catchment with area of 6.7 km in the earth-rock mountain region, which located in the north of Beijing, China, as study area. The catchment bedrock is mainly consist of fractured granite. Four weather stations were installed to observe the weather condition and soil volumetric water content (VWC) at depth of 10-60 cm with 10-minute interval. Five wells with depth of 10 m were drilled in two slopes to monitor the bedrock water table by pneumatic water gauge. At slope 1, the soil VWC at depth of 10-80 cm were also observed by soil moisture sensors, and surface/subsurface hillslope runoff at three different layers (0-20cm, 20-80cm, 80-300cm) was observed by three recording buckets. Field works were conducted from July 2013 to November 2014. During the period, precipitation, river, spring and groundwater were sampled nearly monthly. Water temperature, electrical conductivity (EC) and pH were measured in site with portable instruments. In addition, the precipitation, river and groundwater were also sampled intensively during two storm events. All the samples were subjected to stable isotope analysis, the samples taken monthly during the period from July 2013 to July 2014 were subjected to hydrochemistry analysis. Our results show that: (1) the bedrock groundwater is the dominant component of streamflow in the headwater catchment with sub-humid climate; (2) stream is recharged by groundwater sourcing from different mountains with different hydrochemistry characteristics

  14. The Wageningen Lowland Runoff Simulator (WALRUS): implementation and application to the freely draining Hupsel Brook catchment and controlled Cabauw polder

    NASA Astrophysics Data System (ADS)

    Brauer, Claudia; Torfs, Paul; Teuling, Ryan; Uijlenhoet, Remko

    2014-05-01

    Recently, we developed the Wageningen Lowland Runoff Simulator (WALRUS) to fill the gap between complex, spatially distributed models which are often used in lowland catchments and simple, parametric models which have mostly been developed for mountainous catchments. This parametric rainfall-runoff model can be used all over the world in both freely draining lowland catchments and polders with controlled water levels. Here, we present the model implementation, opportunities for practical application and experience from validation studies with data from two field sites. The open source model code is implemented in R and is set-up such that it can be used by both practitioners and researchers. For direct use by practitioners, defaults are implemented for relations between model variables and to compute initial conditions, leaving only four parameters which require calibration. For research purposes, the defaults can easily be changed. WALRUS is computationally efficient, which allows operational forecasting and uncertainty estimation by creating ensembles. An approach for flexible time steps increases numerical stability and makes model parameter values independent of time step size, which facilitates use of the model with the same parameter set for multi-year water balance studies as well as detailed analyses of individual flood peaks. We applied WALRUS to two contrasting Dutch catchments: the slightly sloping, freely draining Hupsel Brook catchment and the flat Cabauw polder with controlled water levels. In both catchments, WALRUS performs well during the years used for calibration and validation. The model also performs well during extremely wet periods (flash flood in the Hupsel Brook catchment in August 2010) and extremely dry periods (summer 1976) and can forecast the effect of control operations (changing weir elevations and surface water supply).

  15. Authorship in Multi-Disciplinary, Multi-National North-South Research Projects: Issues of Equity, Capacity and Accountability

    ERIC Educational Resources Information Center

    Jeffery, Roger

    2014-01-01

    The challenges of ensuring equity among partners of very different academic power and status, across continents, within complex research projects involving differing disciplines with their own norms, and balancing needs for capacity development of individuals and for institutions can be major sources of conflicts. While each of these concerns has…

  16. Annual Southern Region Research Conference in Agricultural Education Proceedings (35th, North Little Rock, Arkansas, March 22-24, 1986).

    ERIC Educational Resources Information Center

    Rolloff, John A., Comp.

    These proceedings contain a summary of each of the 15 papers presented and the discussants' reactions. The keynote address and reflections on the outcome of the conference are also included. The keynote address is "Priorities for Continuing Progress in Research in Agricultural Education" (J. Robert Warmbrod). Presentations include "Assessment of…

  17. Controls on Nitrate Spatial Variability in Paine Run Catchment of Shenandoah National Park

    NASA Astrophysics Data System (ADS)

    Ingram, S. M.; Scanlon, T. M.

    2007-12-01

    This research examines the catchment-scale controls on in-stream nitrate concentrations by (1) quantifying nitrate spatial variability in a headwater catchment and (2) determining the biophysical processes underlying this variability. The Shenandoah Watershed Study (SWAS) established thirty-eight stream sampling sites in the Paine Run catchment to collect field data on stream chemistry, discharge and transient storage. An evaluation of SWAS data at these sites from the early 1990s to 2007 reveals spatial and temporal variability in nitrate concentrations following the gypsy moth defoliation. We observed high in-stream nitrate concentrations with elevation and an apparent dilution at lower elevations. Main topographic descriptors related to the spatial distribution of nitrate, elevation and contributing area, are associated with differing biophysical factors such as soil residence time, bacterial denitrification, vegetation and mineralization. Previous studies have demonstrated that the physical properties of hyporheic zones can strongly influence denitrification rates. We examined this in the Paine Run catchment with tracer tests to evaluate dilution effects and predict stream outflow and inflow from hyporheic zones responsible for denitrification. We then looked for biophysical processes responsible for higher nitrate levels at higher elevation by using the OTIS model for transient storage to evaluate hyporhiec zones in Paine Run. We also established a method to evaluate soil parameters for depth and permeability. By identifying the controls on nitrate inputs, transport and denitrification, we isolated a set of criteria applied to a quantitative model for nitrate spatial variability. This research has important implications for defining nutrient availability both within the stream network and at the outlet of forested headwater catchments.

  18. Catchment-mediated atmospheric nitrogen deposition drives ecological change in two alpine lakes in SE Tibet.

    PubMed

    Hu, Zhujun; Anderson, Nicholas John; Yang, Xiangdong; McGowan, Suzanne

    2014-05-01

    The south-east margin of Tibet is highly sensitive to global environmental change pressures, in particular, high contemporary reactive nitrogen (Nr) deposition rates (ca. 40 kg ha(-1)  yr(-1) ), but the extent and timescale of recent ecological change is not well prescribed. Multiproxy analyses (diatoms, pigments and geochemistry) of (210) Pb-dated sediment cores from two alpine lakes in Sichuan were used to assess whether they have undergone ecological change comparable to those in Europe and North America over the last two centuries. The study lakes have contrasting catchment-to-lake ratios and vegetation cover: Shade Co has a relatively larger catchment and denser alpine shrub than Moon Lake. Both lakes exhibited unambiguous increasing production since the late 19th to early 20th. Principle component analysis was used to summarize the trends of diatom and pigment data after the little ice age (LIA). There was strong linear change in biological proxies at both lakes, which were not consistent with regional temperature, suggesting that climate is not the primary driver of ecological change. The multiproxy analysis indicated an indirect ecological response to Nr deposition at Shade Co mediated through catchment processes since ca. 1930, while ecological change at Moon Lake started earlier (ca. 1880) and was more directly related to Nr deposition (depleted δ(15) N). The only pronounced climate effect was evidenced by changes during the LIA when photoautotrophic groups shifted dramatically at Shade Co (a 4-fold increase in lutein concentration) and planktonic diatom abundance declined at both sites because of longer ice cover. The substantial increases in aquatic production over the last ca. 100 years required a substantial nutrient subsidy and the geochemical data point to a major role for Nr deposition although dust cannot be excluded. The study also highlights the importance of lake and catchment morphology for determining the response of alpine lakes to

  19. First-order catchment mass balance during the wet season in the Panama Canal Watershed

    NASA Astrophysics Data System (ADS)

    Niedzialek, Justin M.; Ogden, Fred L.

    2012-09-01

    SummaryTropical hydrology is poorly understood for a number of reasons. Intense biological activity in the tropics introduces complexities to the hydrologic process. Bioturbation, rapid rates of decay, and intensive insect activity all tend to promote rapid flow paths in the upper soil. Aggressive weathering leads to clays depleted of light cations and deep soil profiles. Processes in the seasonal tropics are further complicated by seasonal transitions, and very large changes in catchment storage between seasons. Beginning in 2005, we installed a suite of hydrologic sensors in a 16.7 ha first-order catchment in the Panama Canal Watershed to observe hydrologic variables and identify the dominant streamflow generation processes. The site is located near the village of Gamboa, which is located on the east bank of the Panama Canal at the confluence of Lake Gatun and the Chagres River. The study catchment is located on the north side of a ridge off the eastern flank of a 230 m tall hill known as Cerro Pelado, and is covered by 70-120 year old re-growth triple-canopy forest. Measurements included: rainfall above the canopy, throughfall, stemflow, evapotranspiration, shallow groundwater levels and streamflow. Deep groundwater storage was not measured. This paper describes measurements made, data collected, and the worth of those data in estimating the mass balance closure of a first-order catchment during the wet season. We compare measurements of the different components of the water cycle with observations from other published studies from the tropics. Data analysis results indicate water balance closure errors of approximately 8%.

  20. Tidal fluxes of nutrients and suspended sediments at the North Inlet Winyah Bay National Estuarine Research Reserve

    NASA Astrophysics Data System (ADS)

    Gardner, L. R.; Kjerfve, B.

    2006-12-01

    Beginning June of 1993 suites of 13 water samples have been collected at Oyster Landing, North Inlet (SC), every 20 days covering two consecutive tidal cycles at 2.07 h intervals. In order to ascertain whether this large (and still growing) water chemistry data set can be used to determine tidal fluxes of nutrients and sediments, we coupled measured concentrations to estimates of instantaneous tidal discharge based on a basin water storage curve and hindcast tides. The mean advective fluxes of all constituents, including salt, showed statistically significant exports. This result, however, is largely due to an ebb bias in the sampling protocol, which resulted in 52% of the samples being collected on ebb tide versus a theoretical percentage of 48%. When this bias was corrected by reducing the mean discharge (-610 l s -1) to a value (-125 l s -1) that produced a balance between the mean advective and dispersive salt fluxes, the advective fluxes of the other constituents were reduced to values that are not significantly different from zero. In addition to a statistically significant dispersive influx of salt, significant dispersive exports were found for DON, NH 4, DOP, PO 4 and DOC. All particulate constituents (PN, PP, ISS and OSS) yielded dispersive fluxes that were not significantly different from zero. Annual material budgets for the Oyster Landing basin based on the dispersive fluxes of all constituents (except salt) are generally similar in magnitude and direction to those measured by [Dame, R.F., Spurrier, J.D., Williams, T.M., Kjerfve, B., Zingmark, R.G., Wolaver, T.G., Chrzanowski, T.H., McKeller, H.N., Vernberg, F.J., 1991. Annual material processing by a salt marsh-estuarine basin in South Carolina, USA. Marine Ecology Progress Series 72, 153-166.] in the nearby and ecologically similar Bly Creek basin, indicating that the dispersive fluxes determined in this study are realistic. We offer suggestions for improving the reliability and usefulness of future

  1. Patterns and processes of nutrient transfers from land to water: a catchment approach to evaluate Good Agricultural Practice in Ireland

    NASA Astrophysics Data System (ADS)

    Mellander, P.-E.; Melland, A. R.; Shortle, G.; Wall, D.; Mechan, S.; Buckley, C.; Fealy, R.; Jordan, P.

    2009-04-01

    grassland soils; areas where arable production represents a significant landuse; and catchments on productive and unproductive aquifers. The catchments were identified using a GIS-based multicriteria decision analysis with objective criteria that included landuse data (including agricultural and settlement statistics) combined with soils and geology data to evaluate the risk of P and N loss. Shortlisted catchments were then finalised using practical criteria based on the potential for hydrometry and hydrochemistry research. In each catchment, a conceptual model approach is being used to hypothesize the sources, seasonal mobilisation and pathways of nutrients and water through the soil/subsoil system and transfer into surface and ground water systems to stratify each catchment experimental design. Knowledge of the nutrient management of each catchment farm and resulting soil fertility will be used to monitor the sources of agricultural N and P. Environmental soil nutrient tests will provide baselines and checks on the potential for mobilisation. Areas of high soil fertility that are coincident with high surface or sub-surface hydrological connectivity will be monitored for subsequent nutrient transfer. Other potential nutrient source loads within the catchments, such as rural waste-water treatment plants and domestic septic systems, will be factored in as non-agricultural sources. Similarly, the potential for farmyard transfers will also be assessed. The net balance of nutrient transfer at the catchment outlets will be monitored using a high resolution method that is coincident with hydrometric measurements to ensure that there is a full understanding of the inter-dependence between point and diffuse nutrient transfers and hydrodynamics. This source to transfer approach is highly appropriate and a move towards inductive understanding of nutrient use and export in river catchments - the scale at which policies for water resources management will be assessed under the WFD. The

  2. Data mining methods for predicting event runoff coefficients in ungauged basins using static and dynamic catchment characteristics

    NASA Astrophysics Data System (ADS)

    Loritz, Ralf; Weiler, Markus; Seibert, Simon

    2015-04-01

    Transferring hydrological information into ungauged basin by regionalisation approaches is an ongoing field of research. Usually regionalisation techniques use physical landscape descriptors to transfer either model parameters or hydrological characteristics from a catchment to another. A common problem of these approaches is the high degree of uncertainty associated to their results. One reason is that often solely static (structural) catchment characteristics such as catchment area, physiographic properties or land use data are used for regionalisation. However, it is well known that the hydrological response of a 'natural' system is a complex and a non-linear interaction of its structure, state and forcing. Here it is important to note, that only structure is a static property. State and forcing are highly dynamic when considering the temporal and spatial scale of a rainfall-runoff event. To overcome the limitations associated with 'static' regionalisation techniques we propose a regionalisation technique for event runoff coefficients combining static and dynamic catchment properties. The approach is based on the two data mining algorithms 'random forests' and 'quantile regression forests'. The static catchment characteristics include standard variables such as physiographic properties, land cover and soil data. The dynamic variables include event based properties of the forcing (i.e. rainfall amount, intensity,...) and proxies for the initial state of the catchment (i.e. initial soil moisture). Together with the runoff coefficient these quantities were extracted form hydro-meteorological time series (precipitation, discharge and soil moisture) using an automated rainfall-runoff event detection technique. We tested our method using a set of 60 meso-scale catchments (3.1 to 205,6 km2, covering a range of different geologies and land uses) from Southwest Germany. We randomly separated the catchments in two groups. The first group (30 donor catchments) was used to

  3. An ice core derived 1013-year catchment-scale annual rainfall reconstruction in subtropical eastern Australia

    NASA Astrophysics Data System (ADS)

    Tozer, Carly R.; Vance, Tessa R.; Roberts, Jason L.; Kiem, Anthony S.; Curran, Mark A. J.; Moy, Andrew D.

    2016-05-01

    Paleoclimate research indicates that the Australian instrumental climate record (˜ 100 years) does not cover the full range of hydroclimatic variability that is possible. To better understand the implications of this on catchment-scale water resources management, a 1013-year (1000-2012 common era (CE)) annual rainfall reconstruction was produced for the Williams River catchment in coastal eastern Australia. No high-resolution paleoclimate proxies are located in the region and so a teleconnection between summer sea salt deposition recorded in ice cores from East Antarctica and rainfall variability in eastern Australia was exploited to reconstruct the catchment-scale rainfall record. The reconstruction shows that significantly longer and more frequent wet and dry periods were experienced in the preinstrumental compared to the instrumental period. This suggests that existing drought and flood risk assessments underestimate the true risks due to the reliance on data and statistics obtained from only the instrumental record. This raises questions about the robustness of existing water security and flood protection measures and has serious implications for water resources management, infrastructure design and catchment planning. The method used in this proof of concept study is transferable and enables similar insights into the true risk of flood/drought to be gained for other paleoclimate proxy poor regions for which suitable remote teleconnected proxies exist. This will lead to improved understanding and ability to deal with the impacts of multi-decadal to centennial hydroclimatic variability.

  4. Landslide triggering rainfall thresholds estimation using hydrological modelling of catchments in the Ialomita Subcarpathians, Romania

    NASA Astrophysics Data System (ADS)

    Chitu, Zenaida; Busuioc, Aristita; Burcea, Sorin; Sandric, Ionut

    2016-04-01

    This work focuses on the hydro-meteorological analysis for landslide triggering rainfall thresholds estimation in the Ialomita Subcarpathians. This specific area is a complex geological and geomorphic unit in Romania, affected by landslides that produce numerous damages to the infrastructure every few years (1997, 1998, 2005, 2006, 2010, 2012 and 2014). Semi-distributed ModClark hydrological model implemented in HEC HMS software that integrates radar rainfall data, was used to investigate hydrological conditions within the catchment responsible for the occurrence of landslides during the main rainfall events. Statistical analysis of the main hydro-meteorological variables during the landslide events that occurred between 2005 and 2014 was carried out in order to identify preliminary rainfall thresholds for landslides in the Ialomita Subcarpathians. Moreover, according to the environmental catchment characteristics, different hydrological behaviors could be identified based on the spatially distributed rainfall estimates from weather radar data. Two hydrological regimes in the catchments were distinguished: one dominated by direct flow that explains the landslides that occurred due to slope undercutting and one characterized by high soil water storage during prolonged rainfall and therefore where subsurface runoff is significant. The hydrological precipitation-discharge modelling of the catchment in the Ialomita Subcarpathians, in which landslides occurred, helped understanding the landslide triggering and as such can be of added value for landslide research.

  5. Solute Dynamics in a Near-Surface Flowpath-Dominated Forest Catchment

    NASA Astrophysics Data System (ADS)

    Zimmermann, A.; Turner, B. L.; Elsenbeer, H.

    2008-12-01

    Near-surface flowpaths are common in soilscapes that show a pronounced decrease in permeability and that are subject to high rainfall amounts and intensities; Lutz Creek catchment in tropical Panama is no exception. In this catchment, landscape position and antecedent wetness dictate whether overland flow is generated by saturation excess (SOF) or by return flow (RF). In an ongoing study we explore the consequences of these topography-controlled modes of overland flow generation for solute dynamics at different scales: catchment scale and nested subcatchment scale. Total dissolved nitrogen, for example, is higher in RF-dominated than in SOF-dominated subcatchments. Potassium, in contrast, shows higher concentrations in SOF than in RF, and SOF resembles throughfall in this respect, whereas RF does not. Calcium is equally suitable to distinguish between SOF and throughfall on the one hand, and RF on the other. Accordingly, RF-dominated subcatchments show a dynamic within-event response whereas the calcium signal is nearly flat in SOF- controlled subcatchments. We conclude that the topography-controlled and flowpath-mediated hydrochemical signals persist over the extent of our research catchment.

  6. An exploration of coupled surface-subsurface solute transport in a fully integrated catchment model

    NASA Astrophysics Data System (ADS)

    Liggett, Jessica E.; Partington, Daniel; Frei, Sven; Werner, Adrian D.; Simmons, Craig T.; Fleckenstein, Jan H.

    2015-10-01

    Coupling surface and subsurface water flow in fully integrated hydrological codes is becoming common in hydrological research; however, the coupling of surface-subsurface solute transport has received much less attention. Previous studies on fully integrated solute transport focus on small scales, simple geometric domains, and have not utilised many different field data sources. The objective of this study is to demonstrate the inclusion of both flow and solute transport in a 3D, fully integrated catchment model, utilising high resolution observations of dissolved organic carbon (DOC) export from a wetland complex during a rainfall event. A sensitivity analysis is performed to span a range of transport conditions for the surface-subsurface boundary (e.g. advective exchange only, advection plus diffusion, advection plus full mechanical dispersion) and subsurface dispersivities. The catchment model captures some aspects of observed catchment behaviour (e.g. solute discharge at the catchment outlet, increasing discharge from wetlands with increased stream discharge, and counter-clockwise concentration-discharge relationships), although other known behaviours are not well represented in the model (e.g. slope of concentration-discharge plots). Including surface-subsurface solute transport aids in evaluating internal model processes, however there are challenges related to the influence of dispersion across the surface-subsurface interface, and non-uniqueness of the solute transport solution. This highlights that obtaining solute field data is especially important for constraining integrated models of solute transport.

  7. Monitoring temporal changes in use of two cathinones in a large urban catchment in Queensland, Australia.

    PubMed

    Thai, Phong K; Lai, Foon Yin; Edirisinghe, Methsiri; Hall, Wayne; Bruno, Raimondo; O'Brien, Jake W; Prichard, Jeremy; Kirkbride, K Paul; Mueller, Jochen F

    2016-03-01

    Wastewater analysis was used to examine prevalence and temporal trends in the use of two cathinones, methylone and mephedrone, in an urban population (>200,000 people) in South East Queensland, Australia. Wastewater samples were collected from the inlet of the sewage treatment plant that serviced the catchment from 2011 to 2013. Liquid chromatography coupled with tandem mass spectrometry was used to measure mephedrone and methylone in wastewater sample using direct injection mode. Mephedrone was not detected in any samples while methylone was detected in 45% of the samples. Daily mass loads of methylone were normalized to the population and used to evaluate methylone use in the