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PublicationsResearch on Water Treatment for Pesticide Removal and
the Impacts of Agriculture on Water Quality
ORD/NCER STAR Grants
Research on Water Treatment for Pesticide Removal and the Impacts of Agriculture on Water Quality December 2000 Introduction The research projects described below are funded by NCER grants. Research projects are divided into two main areas that include:
For ease of understanding, all grants have been placed under topic areas that describe the overall, general objectives of the projects. Specific information is given for each grant that includes: title, web address, EPA grant number, principal investigator(s), institution (university), NCER project officer, dates during which the grant is funded, and a brief description of the research. NCER STAR GRANTS ON WATER TREATMENT FOR PESTICIDE REMOVAL Application of Surface Expresses Phosphotriesterase for Detoxification
and Monitoring of Organophosphorus Pesticides The proposed research will seek to develop a novel method for biodegradation of organophosphorus pesticides in an immobilized cell bioreactor using E. coli with surface-exposed phosphotriesterase as "live" biocatalysts and to couple the reactor with a flow injection system for the detection of organophosphorus pesticides. Parathion, being the most frequently employed organophosphate pesticide in the US, will be used to demonstrate the potential of this new method. Anaerobic Biodegradation of 2,4,6-Trinitrotoluene and other
Nitroaromatic Compounds by Clostridium Acetobutylicum Nitroaromatic compounds are widely used in the synthesis of dyes, pesticides, pharmaceuticals and munitions and have become common contaminants of soil, sediments, and water. The purpose of this project is to investigate the anaerobic biotransformation of TNT and other nitroaromatics under highly controlled conditions using cultures of Clostridium acetobutylicum. Results show that aminated nitrotoluenes were not detected during TNT transformation. Instead hydroxylamino-compounds constituted the only aromatic transformation intermediates observed. The second major finding to date is the influence of the metabolic activity of the culture on the initial stages of nitro-reduction. This result has practical applications in the operation of anaerobic bioremediation systems for treatment of nitroaromatics. Papers and Publications Pucik, L. E., and J. B. Hughes, "Capillary Electrophoretic Separation of TNT and TNT-Transformation Products," Journal of Capillary Electrophoresis -- accepted. T. A. Khan, R. Bhadra, and Hughes, J. B., "Transformation of TNT and Related Nitroaromatics by Clostridium acetobutylicum," Journal of Industrial Microbiology -- accepted. T. A. Khan (1996), "Transformation of TNT and Related Nitroaromatics by Clostridium acetobutylicum," M. S. Thesis. Rice University Pucik, L. (1996) "The Fate of TNT Reduction Products in Aerobic Microbial Systems," M. S. Thesis. Rice University Other Research on Water Treatment for Pesticide Removal NCER RESEARCH ON THE WATER QUALITY IMPACTS OF AGRICULTURE Science Questions and Issues
that NCER Is Addressing Related to the Water Quality Impacts of
Agriculture • How Does Agriculture Effect
Water Resources And Aquatic Fauna? Other Research on the Water Quality Impacts of Agriculture HOW DOES AGRICULTURE EFFECT WATER RESOURCES AND AQUATIC FAUNA? CISNet for the Neuse River Estuary, NC: A Program for Evaluating
Nitrogen Driven Eutrophication Associated with Changing Land Use
in a Coastal Watershed The overall objective of this proposal was to build upon the historical water quality database in the Neuse River Estuary. The specific research components are: (1) bi-weekly monitoring of water quality; (2) determination of atmospheric nitrogen (N) loading; (3) quantification of N loading from a large coastal farm; (4) continuous monitoring of circulation; and (5) data management, archival, and integration. Bi-weekly water quality monitoring at 19 mid-estuary stations was conducted. Compared to 1994-1998, freshwater discharge to the Neuse estuary was low until late summer 1999. The mainstem channel was stratified and the bottom water was hypoxic through most of the summer.
Progress Report: Aquatic - Rivers and Estuaries The overall goal of this research is to determine the adverse effects of multiple stressors on tissues, cells and macromolecules of fish, crayfish and fish-eating birds within a waterway and to incorporate these findings into hydrodynamic and biologically-based models enabling better understanding of the role of multiple stressors in population level responses. The Sacramento River, its Delta and upper San Francisco Bay comprise a heavily managed ecosystem. Dams store snow melt and release water for contracted agricultural and municipal usage. Large exports of water support irrigation of crop lands and municipal and domestic usage. The system is stressed by transport of water from the river by dams and diversions that disrupts both waterflow patterns and fish-population movements. It is also stressed by deteriorating water quality due to pesticide runoff, nutrient enrichment, mine drainage, saline intrusion from the ocean and elevated temperatures. Studies are continuing with the embryos and multiple stressor effects are being investigated. These include salinity, temperature and anthropogenic compounds (pesticides, herbicides, metals). 1998 Progress Report: Modeling Effects of Alternative Landscape
Design and Management on Water Quality and Biodiversity in Midwest
Agricultural Watersheds Research has generated alternative future scenarios that explore a range of human land use and management choices for watersheds in the cornbelt region of the United States. Species-habitat matrices for nonfish vertebrates of central Iowa were and sent out for expert review. Efforts were begun to calibrate the Environmental Policy Integrated Climate economic simulator model. At our all-project meeting (July 1998), we shared results of preliminary model runs on current land cover and first drafts of future scenarios. HOW CAN WE REDUCE AGRICULTURAL IMPACTS ON WATERSHEDS? Riparian Poplar Tree Buffer Impact on Non-point Source Surface
Water Contamination: A Paired Agricultural Watershed Study Objectives are to develop a paired watershed research site sufficiently
instrumented to develop a hydrologic, silt, and agricultural chemical
movement database; to compile the watershed basin data in a form
usable with existing EPA and USDA models to understand the impact
of perennial tree buffers on the runoff water quantity and quality
from "conventionally" farmed land; to install alternative
perennial plant buffer designs to compare plant survival, biomass
growth potential, sediment interception, subsurface nitrate movement
in near-surface ground water, and herbicide movement from up-gradient
application to the stream; to test equipment and tillage practices
required by farmers to make this plant production practical; and
to develop an education and technology exchange program to explain
watershed-scale conservation and cropping concepts to 1999 Progress Report: An Integrated Ecological and Socio-Economic
Approach to Evaluating and Reducing Agricultural Impacts on Upper
Mississippi River Watersheds The objectives of this research project are to: (1) use a spatial-process
model to predict agricultural discharges from the Lower Minnesota
River watershed in eastern Minnesota, the Maquoketa River watershed
in northeastern Iowa, and Big Darby Creek watershed in central Ohio
; (2) use observed and predicted runoff, sediment, and nutrient
loadings to estimate the contribution of urban areas, wastewater
treatment plants and point sources to the total loading; (3) use
the model to evaluate potential water quality benefits associated
with the adoption of alternative management strategies on these
watersheds; (4) develop regional-scale predictive models of ecosystem
‘health,' biodiversity, and sustainability by relating information
on biota and ecosystem functional processes to current and potential
landscape composition and structure; and (5) identify factors that
affect adoption of conservation production systems among land owner-operators
in the two watersheds. Findings reveal that many farmers within
the three watersheds had adopted soil and water conservation protection
practices. However, they also reported using production practices
that could negate many of the environmental benefits associated
with conservation practices currently in use. Findings strongly
suggested that conservation initiatives should place emphasis on
"whole farm planning" so that all production practices
used on a specific farm will be complementary. Watershed Protection in Agricultural Environments: Integrated
Social, Geomorphological, and Ecological Research to Support Ecosystem-based
Stream Management The objectives of the proposed research are to: 1) examine the social dynamics of community-based watershed projects, particularly the social context of local agents and institutions (local stakeholders) within which scientific knowledge about watershed protection is absorbed and acted on, and 2) to provide an improved scientific understanding of the connection between the geomorphological dynamics and ecological integrity of human-modified stream systems in the agricultural Midwest. HOW ARE AGRICULTURE AND OTHER FACTORS LINKED TO WATER QUALITY? Final Report: Influences of Watershed Land Use on Stream Ecosystem
Structure and Function This research had two objectives: (1) to determine how differing patterns of land use in the watershed alter stream ecosystem structure and function, and (2) to compare measures of stream ecosystem function (rates of community metabolism and transport and cycling of carbon and nutrients) with traditional chemistry-based water quality assessment and organism-based bioassessment. Streams were placed in forest, agricultural (poultry and livestock production), urban, and suburban categories based on GIS analyses of land use in the watershed. Percent impervious surface varied greatly as a function of dominant land use in the watershed: less than 1 percent in forested and agricultural watersheds, 17–22 percent in suburban watersheds, and 32–37 percent in the urban watersheds. Gross primary production was generally higher in agricultural streams and lower in urban and suburban streams. Community respiration was generally higher in forest and urban streams than in agricultural or suburban streams. Uptake length for both NH4 and PO4 was significantly greater in urban streams (1630 ± 250 m and 2030 ± 540 m for NH4 and PO4, respectively) than in forest streams (550 ± 100 m and 590 ± 140 m), meaning that nutrients were removed more slowly from the water column in urban streams. Urban and suburban streams had greatly reduced fine particle retention, largely because of decreases in hydraulic complexity and in-stream retention structures, which reduced the size of transient storage zones. Retention of leaf material was also lowest in urban streams. See web site for numerous publications related to this research. Final Report: Integrating Planning, Forecasting, and Watershed
Level Ecological Risk Assessment Techniques: A Test in the Eastern
Cornbelt Plains Ecoregion The objectives of this research were to: (1) test the relationships between biological conditions of streams and the nature and distribution of human activities on the watershed; (2) demonstrate methods for linking physical models of urban and agricultural impacts on runoff volume and runoff quality; (3) define the relationships between physical model forecasts and the biological conditions of streams; and (4) integrate all of the findings into an expert system to be used by planners. Using a comprehensive regional database and regression models, we tested watershed-scale relationships between biological measures of water quality and watershed characteristics. The study was conducted on the Darby Creek Watershed in central Ohio. See web site for numerous publications related to this research. Water and Sustainable Development in the Binational Lower Rio
Grande/Río Bravo Basin The objectives of this research were to develop, compare and integrate reliable, comparable watershed-based data sets for the Lower Rio Grande/Río Bravo Basin. In addition, to analyze water resource issues as critical factors for achieving sustainable development in this type of watershed. Data are being collected in the areas of water supply, including quantity and quality; water demands from municipal, industrial, agricultural and ecological users; water management and institutions; in-stream habitat; and population and socioeconomic growth. 1999 Progress Report: The Choptank River: A Mid-Chesapeake Bay
Index Site for Evaluating Ecosystems Responses to Nutrient Management The primary goal of this research is to develop and examine methods for detecting responses to anthropogenic stresses in the Choptank River Index Site and to establish the site as a sentinel of change for a broader domain of coastal plain ecosystems. The intent is to resolve responses caused by human activities from the variability imposed by nature, to develop key indices of ecosystem change, and to predict trends and their consequences. Monthly shipboard and remote surveys along the 60-km axis of the Choptank River were initiated in January 1999. Chlorophyll concentrations were low in both tributaries compared with long-term averages. These low concentrations were likely associated with low flow from the rivers and tributaries of the Chesapeake Bay during the protracted drought, and mirrored low chlorophyll concentrations in the main stem of the Bay.
1999 Progress Report: A Comparison of Agricultural vs. Forested
Basins: Carbon and Nutrient Cycling Within the Hyporheic Ecotone
of Streams Processes and patterns within the hyporheic zone—the interface between groundwater and surface water beneath streams—may help explain differences in stream functions between forested and agricultural basins. This study focuses primarily on third order reaches of two basins, one in a forested ecosystem, the other in an agricultural basin. Preliminary results show that the effects of siltation on hyporheic processes directly beneath the stream were minimal. What appears to be equally or even more important than silt deposition is the increased runoff that comes from agricultural and rural development. Increased runoff alters the physical structure of stream channel. The size and extent of gravel bars are greatly increased, which results in much larger lateral areas of hyporheic storage and processing. See web site for numerous publications related to this research. 1996 Progress Report: Potential for Long-Term Degradation of Wetland Water Quality Due to Natural Discharge of Polluted Groundwaterhttp://cfpub.epa.gov/ncer_abstracts/index.cfm/fuseaction/display.abstractDetail/abstract/1783/report/1996 EPA Grant Number: R825433C001 Investigators: Graham Fogg (Land, Air and Water Resources) and Miguel Marino (Land, Air and Water Resources) Institution: NCER Center for Ecological Health Research (Cal-Davis) Project Period: 6/30/95 - 1/1/2000 The purpose of this research is to assess the impact of chemicals introduced by agricultural and industrial activities on the quality of subsurface water and exposure levels of contaminants in groundwater discharged to wetlands and rivers. New numerical and analytical methods for probabilistically quantifying origins and ages of ground waters arriving at discharge points (e.g., wetlands, wells) have been developed that rigorously account for the physical processes involved in pollutant transfer between different geologic materials. Results indicate that currently observed deterioration in groundwater quality in a typical alluvial groundwater basin is due to land use practices in the late 1940's and 1950's and that the deterioration may continue for many decades, thereby eventually impacting any wetlands and streams that are sustained by groundwater discharge. Efforts have been initiated to develop models to link the chemical source at the surface to groundwater. 1999 Progress Report: Effects of Interacting Stressors in Agricultural
Ecosystems: Mesocosm and Field Evaluation of Multi-Level Indicators
of Wetland Responses Our primary objective is to evaluate indicators of molecular, cellular, population, community, and ecosystem responses to multiple, potentially interacting, natural and anthropogenic stressors that vary at different spatial and temporal scales in agricultural wetlands. We have characterized physical features, land use practices, and potential pesticide loads in the Little Tallahatchie River Basin in northern Mississippi. From the chemical distributions, we have identified map sections most likely to have wetlands with agrichemical loadings typical of the single or multiple stressor treatments in our mesocosm experiments. 1999 Progress Report: Land Use and Geomorphic Indicators of
Biotic Integrity in Piedmont Streams The main objective of this research is to define the predictive capabilities of scale-variable attributes of land cover (GIS-based) and geomorphology as risk assessment indicators of biotic integrity of stream ecosystems. The watershed under investigation is the Etowah River basin, north of Atlanta, Georgia..We have selected 30 streams (10 each in 15, 50, and 100 km2 watersheds), characterized the land use and geomorphic condition, and assessed biological integrity at each site. Stream chemistry changed along the gradient of land use. Phosphorus, ammonium, nitrate, and specific conductance all increase as a result of decreasing forested land use, but some of the responses show scale dependency.
Integrating Modeling and Management of Agriculturally-Impacted
Watersheds, Issues of Spatial and Temporal Scale We will conduct the research in three coordinated phases: landscape processes, aquatic processes, and social-economic issues. Research will focus on (1) ways to account for scale effects in hydrologic and nutrient transport modeling within watersheds; (2) understanding the effectiveness of agro-ecosystems as complementary landscape units (to watersheds) for analysis of nutrient export from the land; (3) understanding of scales at which aquatic ecosystems process and retain nutrients and how they influence rates of stream recovery when land management practices are improved; and (4) ways to identify priorities for controlling diffuse sources of sediments and P based on technical, social, and economic feasibility. Fellowship - Agricultural production results in the loss of
unutilized nutrients such as nitrogen (N) and phosphorus (P) to
ground and surface waters Agricultural production results in the loss of unutilized nutrients such as nitrogen (N) and phosphorus (P) to ground and surface waters. This research will focus on developing techniques to significantly reduce the amounts of N and P which escape the farm and accumulate in the environment. The focus of my work is to discover animal management methods which will reduce nutrient losses from dairy farms. CAN WE DETERMINE THE ORIGIN OF WATER CONTAMINANTS? 1999 Progress Report: Detecting and Characterizing Fecal Contamination
and Its Sources in Ground and Surface Water (Watersheds and Aquifers) The objectives of this research are to develop, evaluate, and apply new and improved methods to detect, quantify, and distinguish between human and animal fecal contamination in watersheds and aquifers to trace and identify fecal contamination sources. Progress was made in developing new and improved methods to recover and detect enteric microbial pathogens and indicators in water and wastes, with particular emphasis on the recovery of all microbes from water by hollow fiber ultrafiltration, and the detection and quantitation of somatic and male-specific coliphages and the potentially pathogenic bacterium Yersinia enterocolitica.
The Role of Colloidal Particles in the Transport of Chemicals
Through an Agricultural Watershed This project takes an integrated approach in evaluating the important controls on the fate of a widely used herbicide (atrazine) from initial occurrence in the unsaturated soil zone in an agricultural area to occurrence in the groundwater of a bedrock water-supply aquifer to appearance in a stream draining the watershed. We found that the extent of hydroxyatrazine penetration into sand beds is sensitive to influent colloid concentration, infiltration rate, and colloid mineralogy. Colloids isolated from the soil were found to have up to three orders of magnitude more extensive adsorption of atrazine than the bulk soil. Nevertheless, only a fraction (about 10%) of observed atrazine transport at our site was associated with fine particles. We examined atrazine, dissolved organic carbon (DOC), suspended sediment, silica, and major ion concentrations in the streamwater, overland flow, soil water, and groundwater during the summer of 1998. Sampling was initiated following springtime pesticide and fertilizer application. The results indicate that, in general, about 10 percent of the transport occurred as sediment-associated atrazine. Analyses suggest a relationship between atrazine sorption and elevated DOC and potassium concentrations, but reduced nitrate levels. We hypothesize that sorption of atrazine to mobilized manure particles is responsible for the observed sediment-associated atrazine transport. Sediment-associated atrazine is highest in overland flow that contains the highest concentrations of suspended particles. Once the overland flow is diluted by soil water and streamwater, desorption lowers the fraction of atrazine associated with sediments. See web site for numerous publications related to this research. Molecular Tracers of Contaminant Sources to Surface Water Drinking
Supplies The objective of this research is to develop a more quantitative method for apportioning the contribution of contaminants from point source effluents and nonpoint source runoff to surface waters that are drinking water supplies (e.g., rivers and reservoirs). In preliminary research, we developed a suite of molecular tracers for several potential contaminant sources that included waste water treatment plants, agricultural runoff, urban/suburban runoff, and wildlife. A nonparametric Bayesian approach for quantifying herbicide
exposure in streams This research proposes to use benthic algae to detect and quantify low-level herbicide concentrations and their cumulative effects in agricultural basin streams. Fellowship - Use of Mathematical Modeling Techniques to Predict
Dairy Cow Management Strategies That Will Reduce Nutrient Losses
to the Environment The goal of this research is to contribute to the reduction of nutrient losses from animal agriculture systems to the environment. The project will use mathematical modeling to integrate existing data pertaining to nitrogen (N) and phosphorus (P) losses from and flows within dairy farms.
CAN WE USE MODELS TO ESTIMATE CHANGES IN WATER QUALITY? 1999 Progress Report: An Integrated Approach To Assessing Water
Management Options in a Major Watershed: Expanding a Hydrodynamic-Water
Quality Model To Include Biological and Politico-Economic Components Hydrodynamic (water surface elevation and flow) and water-quality (temperature and salinity) models have been calibrated for 1984 (April-June, a "wet" year), 1992 (April-December, a "dry" year), and 1993 (January-June, an "above average" year) using a substantially improved grid. The individual-based striped bass model (relating population dynamics to flows, temperature, salinity, and toxins) has been improved. A model relating water supply to cropping patterns, pesticide usage, and nutrient loadings on 8,000 fields in Glenn and Colusa counties is being developed. Funding has been obtained to look at the effect of various water management options on urban water supplies. We are also modeling the impact of five different management scenarios on water quality, salmon and striped bass, and agricultural and urban water use. See web site for numerous publications related to this research. Linking Environmental and Social Performance Measurement for
Management at National and Watershed Levels: Modeling and Statistical
Approaches The objectives of the study are to: 1) estimate year-to-year changes in water quality for conventional water-quality parameters at the national and watershed level by using index numbers, and multivariate and ordered mean rates of change for conventional and toxic pollutants, 2) estimate the net benefits of alternative policies for Total Maximum Daily Loads (TMDL) trading, 3) estimate the economic benefits of water quality improvement at the watershed level, 4) improve modeling of wet weather events in a policy model, and 5) estimate the link between water quality pollution abatement and control expenditures at the facility level and water-quality performance indicators for the nation and specific regions and watersheds. Integrating Modeling and Management of Agriculturally-Impacted
Watersheds, Issues of Spatial and Temporal Scale HOW DOES URBANIZATION EFFECT WATER QUALITY? Alternative Urbanization Scenarios for an Agricultural Watershed:
Design Criteria, Social Constraints, and Effects on Groundwater
and Surface Water Systems Agricultural landscapes are being urbanized throughout the United States, resulting in the degradation of aquatic systems. Fundamental changes in watershed hydrology result from the construction of impervious surfaces (roofs, streets, sidewalks).We propose to evaluate alternative management practices and patterns of urbanization by considering a range of urban development issues, including storm runoff, groundwater depletion, wastewater treatment, eutrophication, and wetland degradation. We will also address the interaction among these issues and the social and political opportunities for, and constraints on, effective management. Other Research on Water Treatment for Pesticide Removal ORD's National Risk Management Research Laboratory in Cincinnati, Ohio has done an extensive amount of work on water treatment methods for pesticide removal. Information can be obtained from: Thomas Speth at: http://www.epa.gov/ORD/NRMRL/wswrd/ Also information can be obtained from EPA's Office of Science Technology
in the Office of Water: Other Research on the Water Quality Impacts of Agriculture Many states and federal agencies monitor water bodies for pesticides
and nutrients used in agriculture. One of the best sources for this
type of information is the US Geological Survey's National Water-Quality
Assessment Program at: http://water.usgs.gov/nawqa/
In addition, EPA's Office of Pesticide Programs is working on a database entitled "The Pesticides in Ground and Surface Water Database," a national compilation of monitoring data. The database is not yet online but should be in the near future. For details, contact Dan Rieder at rieder.daniel@epa.gov The US Department of Agriculture's Agricultural Research Service
(ARS) is also doing research in this area. Current research projects
being conducted at the National Soil Tilth Laboratory can be found
at: http://www.nstl.gov/research/current.html. Research being done
by the ARS's Water Management Unit can be found at: http://www.wmuinfo.usda.gov
(under "Projects").
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