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Showing 1 to 20 of 23 for “"NPS pollution"”.
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Use Of Small Format Aerial Photography in NPS Pollution Control Applications
An automated procedure was developed to identify and extract confined poultry facilities from color 35-mm slide imagery collected by the United States Department of Agriculture/Farm Service Agency (USDA/FSA). The imagery is used by the USDA/FSA to monitor compliance with various farm support …
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SET-WET: A Wetland Simulation Model to Optimize NPS Pollution Control
… wetlands in order to optimize non-point source (NPS) pollution control measures. The model simulates the hydrologic, nitrogen, carbon, dissolved oxygen, bacteria, vegetative, phosphorous and sediment cycles of a wetland system. Written in Fortran 77, SET-WET models both free water surface (FWS) …
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A subsurface water quality evaluation system for assessing NPS pollution potential by pesticides
A watershed scale water quality evaluation system was developed for assessing spatial variation of subsurface pesticide movement. The system consists of a linked-transport model component for performing simulation and a GIS component for processing spatially-related data. The surface heterogeneity …
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Two analyses of costs of agricultural NPS pollution: Transactions costs of expanding nutrient trading to agricultural working lands and Impacts of TCs and differential BMP adoption rates on the cost of reducing agricultural NPS pollution in Virginia
… efforts to reduce agricultural nonpoint source (NPS) pollution in the Virginia portion of the CB watershed. Firstly, current and possible future transactions costs associated with specific aspects of agricultural NPS participation in water quality trading (WQT) programs are examined in Chapter 1. …
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Surface-subsurface interactive flow simulation using a surface element concept
… urban development. Protecting clean water from pollution is an important goal. One category of water pollution is called ""Nonpoint Source Pollution"" (NPS). This category includes all sources that do not issue from a distinct pipe or outlet. Most of NPS pollution does migrate with surface and …
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Nonpoint source pollution modeling of an agricultural watershed within a geographic information system
… made in the past two decades, nonpoint source (NPS) pollution continues to be an important environment management and water quality management problem. For the most part, analysis of NPS pollution in watersheds has depended on the use of lumped mathematical models to identify potential problem …
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Parameter uncertainty in nonpoint source pollution modeling
… nature of inputs in nonpoint source (NPS) pollution modeling and the lack of information in many cases results in considerable uncertainty in model input parameters, and therefore, model outputs. Uncertainty in input parameters has important implications for model use in simulation …
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Applying Probabilistic Risk Assessment to Agricultural Nonpoint Source Pollution
… of excessive nitrogen from nonpoint sources (NPSs) to a stream was performed for a small agricultural watershed in northern Virginia. Risk, by definition, is the product of the frequency of occurrence of an event and the consequences of that event. The purpose of this research was to determine …
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Procedure to Quantify Environmental Risk of Nutrient Loadings to Surface Waters
… the watershed to environmental degradation, pollution problems, and a decrease in water quality if resources and activities within a watershed are not managed carefully. In order to best utilize limited resources and maximize the results with respect to time and money spent on nonpoint source …
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A Comparative Study of Stream-Gaging Methods Employed in Nonpoint Source Pollution Studies in Small Streams
… with the rising concern about nonpoint source (NPS) pollution. NPS pollution studies, such as TMDL development, often involve quantification of flow in small first and second order streams. This application of technology intended for use in larger streams presents special problems that must be …
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Modeling Fate and Transport of Nitrogen and Phosphorus in Crop Fields Under Tropical Conditions
… important tool for developing nonpoint source (NPS) pollution control plans. Current NPS models were developed for temperate conditions and, thus, do not appropriately represent tropical conditions. The objective of this research was to develop or adapt a nonpoint source pollution model to …
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Modeling Farm-Level Costs of the Yield Reserve Program
Nonpoint Source (NPS) pollution, pollution that comes from diffuse sources that are difficult to trace back to a single point such as farm fields, is a major concern affecting America's water ways. Nationally, agriculture is the leading source of water impairment and has also been identified as the …
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Controlling nonpoint pollution in Virginia's urbanizing areas: an institutional perspective
… and enforcement of nonpoint source (NPS) pollution control measures in the state's urbanizing areas. The institutional framework is developed primarily around the existing governmental framework. The federal, state and local roles are examined in terms of the relevant legislative and …
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A mathematical model of the nitrogen cycle in a constructed wetland
… differences. Constructed wetlands for use in NPS pollution control are a new concept; there is no data currently available to use for model validation. The model was shown to be consistent with qualitative theoretical considerations, based on simulations of different scenarios.
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An Assessment of the Quality of Agricultural Best Management Practices in the James River Basin of Virginia
… be treated equally when accounting for BMPs in NPS pollution in watershed management and computer modeling. Currently, only cost-share practices are included in computer models, in part because these are the only practices tracked by the existing BMP establishment infrastructure. Estimating the …
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Assessing the Current State and Future Outlook of Lake Murray Watershed, South Carolina
… of point source as well as non-point source (NPS) pollution runoff and therefore, the environmental conditions in the watershed. This research examined land cover types surrounding the waterfront of Lake Murray to give a snapshot of the current state of the lake and a glimpse at what the …
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A Whole-Farm Planning Decision Support System for Preventive Integrated Pest Management and Nonpoint Source Pollution Control
… pest management (IPM) and nonpoint source (NPS) pollution control was designed, implemented and evaluated. The objective of the system was to generate plans at the farm level to satisfy economic and production goals while limiting risks of insect pest outbreaks, nitrate and pesticide …
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Understanding the role of scale in assessing sediment and nutrient loads from Coastal Plain watersheds delivered to the Chesapeake Bay
… the principal contributor to non-point source (NPS) pollution and subsequent impairments of streams, rivers, lakes, and estuaries. Urban and agricultural runoff is a major source of sediment, nitrogen (N) and phosphorus (P) loading to receiving waters. Coastal waters in the southeastern U.S. are …
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The Hillslope Hydrology of a Mountain Pasture: The Influence of Subsurface Flow on Nitrate and Ammonium Transport
Nonpoint source (NPS) pollution is possibly the greatest form of contamination to our nation's waters. Nutrient pollutants, such as nitrate and ammonium, often enter aquatic ecosystems through surface and subsurface hydrological transport that drain agricultural watersheds. The over-abundance of …
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Evaluation of Continuous Flow Constructed Wetlands Treating Swine Waste
… any activities resulting in non-point source pollution (NPS). Livestock waste is considered one of the leading causes of NPS pollution which has created this awareness for better waste management. As traditional waste treatment equipment is commonly too expensive for the average livestock …
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