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281.
282.
Abstract: For a number of years, best management practices (BMPs) have been implemented within the Town Brook watershed as part of a watershed wide effort to reduce phosphorus losses to the New York City water supply reservoirs. Currently, there are no quantitative indications of the effectiveness of these practices at the watershed scale. Additionally, work is needed to evaluate management practice solutions for costs in relation to effectiveness. In this study we develop a methodology for evaluating management solutions to determine the best way(s) to select and place management practices so that pollutant removal targets are met at minimum cost. The study combines phosphorus losses as simulated by the Soil and Water Assessment Tool (SWAT), management practice effectiveness estimates from a predeveloped characterization tool, and practice costs in optimizations using a genetic algorithm. For a user defined target phosphorus removal (60 percent for this study), optimization favors nutrient management plans, crop rotations, contour strip cropping, and riparian forest buffers; the most cost effective scenario achieves a cost effectiveness of 24/kg phosphorus removal per year compared to the 34/kg phosphorus removal per year associated with the current basic implementation scheme. The study suggests that there is a need to evaluate potential solutions prior to implementation and offers a means of generating and evaluating the solutions.  相似文献   
283.
ABSTRACT: Research suggests that conflict over public participation in water resource planning is due, in part, to confusion over the nature of the policies involved. This article examines the roadblocks to citizen involvement in water resource planning in terms of two policy models: (1) the Social Feasibility Model and (2) the Political Feasibility Model. Each model posits a different role for public participation. Although the Political Feasibility Model has been widely accepted in water resource planning, changes in the nature of the policies involved in water resource management have weakened its appropriateness. Currently, social and redistributive policies involving value conflicts often dominate water planning and these policies are best chosen through the Social Feasibility Model. The article discusses the nature of the social feasibility model, the new types of policy decisions facing water resource managers, and how the social feasibility model can help overcome the roadblocks to increased public participation in water resource policy making.  相似文献   
284.
The study of the negotiation process has enjoyed a recent resurgence of scholarly interest. Of particular concern is the ability of negotiators to achieve solutions which result in integrative outcomes. The purpose of this study is to identify the effects of different levels of aspiration/goals on negotiator success and their ability to reach integrative solutions in a competitive market. One hundred fifty-eight subjects who were assigned one of four levels of goal difficulty-no goal, compromise goal, challenging goal, and difficult goal-participated in a competitive, multi-person, multi-transaction market simulation. The study found (1) challenging and difficult goals significantly enhanced participants' performance; (2) the more difficult the goal, the fewer transactions were completed; and (3) while there were no differences in total profitability among the challenging goal, compromise goal, and no goal, the difficult goal condition had a significant and negative effect on the ability of participants to achieve profitable outcomes within the market. A discussion of these findings and directions for future research are presented.  相似文献   
285.
Targeting of agricultural conservation practices to the most effective locations in a watershed can promote wise use of conservation funds to protect surface waters from agricultural nonpoint source pollution. A spatial optimization procedure using the Soil and Water Assessment Tool was used to target six widely used conservation practices, namely no‐tillage, cereal rye cover crops (CC), filter strips (FS), grassed waterways (GW), created wetlands, and restored prairie habitats, in two west‐central Indiana watersheds. These watersheds were small, fairly flat, extensively agricultural, and heavily subsurface tile‐drained. The targeting approach was also used to evaluate the model's representation of conservation practices in cost and water quality improvement, defined as export of total nitrogen, total phosphorus, and sediment from cropped fields. FS, GW, and habitats were the most effective at improving water quality, while CC and wetlands made the greatest water quality improvement in lands with multiple existing conservation practices. Spatial optimization resulted in similar cost‐environmental benefit tradeoff curves for each watershed, with the greatest possible water quality improvement being a reduction in total pollutant loads by approximately 60%, with nitrogen reduced by 20‐30%, phosphorus by 70%, and sediment by 80‐90%.  相似文献   
286.
Environmental Science and Pollution Research - Lead (Pb) poisoning is a major public health concern in environmental justice communities of the USA and in many developing countries. There is no...  相似文献   
287.
Environment, Development and Sustainability - The many widely reported significant environmental changes in sub-Saharan communities caused by population change and expansion of built-up areas have...  相似文献   
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