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131.
Jackie Sellers Ronald M. North 《Journal of the American Water Resources Association》1979,15(1):167-181
ABSTRACT: The “principles and standards for planning water and related land resources” were made effective October 25, 1973. The document was noticeably deficient in suggestions for the necessary implementing procedures to ensure its success. Current implementing procedures are based on an incorrect premise of maximizing a single objective subject to non-quantified constraints. A successful implementation of multiple objective planning requires optimizing simultaneously several competitive goals. A system of goal programming has been developed and applied to decisionmaking situations as a test of its usefulness in planning for multiple objective water resources projects. The result is a project planning process which can be replicated for adjustments in expected resource supplies or demands to provide a tradeoff matrix between economic and environmental objectives as well as traditional functional purposes. This procedure, tested on the Cross Florida Barge Canal, is an integrated analysis of economic and environmental values which may be as effective in implementing multiple objective planning as the “Green Book” was in developing the now inappropriate benefit cost analysis. 相似文献
132.
A procedure is outlined which allows consideration of both objective and subjective indicators to establish priorities in plan implementation of water resource development. The objective procedure utilizes stepwise multiple discriminant analysis to predict community performance regarding planned project implementation, based on previous project implementation in the Northeast. The subjective procedure incorporates prior probabilities developed by the planner, based on observation and experience gained through the planning process. The proposed analysis could eliminate waste through better allocation of planning funds to implementation studies exhibiting higher probability of early implementation. 相似文献
133.
John C. Clausen Kenneth N. Brooks 《Journal of the American Water Resources Association》1983,19(5):769-772
ABSTRACT The impacts of milled peat mining on runoff quality in northern Minnesota were determined using a multiple watershed approach. The frequency distributions of water quality constituents were used to detect whether runoff from a mined bog differed from that of 15 unmined (control) bogs. Peat mining increased water temperature, suspended sediment, specific conductance and concentrations of acidity, iron, sodium, and nitrogen species, although drinking water standards were not exceeded (α= 0.05). The method presented may be applicable for other nonpoint pollution investigations. 相似文献
134.
Manfred Fehr 《Resources, Conservation and Recycling》1998,22(3-4)
An integrated network is conceived that qualitatively relates environmental actors and environmental systems within a social unit such as a town, an industrial district or the like. The resulting matrix shows the flow of decisions and information between its active vector representing the environmental objectives, and its passive vector representing the environmental achievements. By way of three additional vectors, the properties of environmental systems are determined and compared to the expectations created by provisions of the environmental actors. The result is a set of residuals that define the living comfort in the social unit. The network motivates interested parties such as administrations, schools or individuals to go through the exercise of finding the causes of the residuals. In order to eliminate them, definite responsibilities have to be assigned to community members. The study pretends to involve all citizens in the flow of information, facts and decisions, and to help them identify themselves in the matrix. It is anticipated that as a result of this educational exercise, individual and collective responsibilities become apparent and are accepted and practiced. 相似文献
135.
Targeting Water Reuse with Multiple Contaminants 总被引:1,自引:0,他引:1
136.
Diana Valiela Paul H. Whitfield 《Journal of the American Water Resources Association》1989,25(1):63-69
ABSTRACT: Two sampling strategies designed to test for compliance with water quality objectives are examined. For objectives based on long-term mean requirements, fixed frequency sampling at frequent intervals is most advantageous regardless of the underlying distribution of the data. For objectives that are based on maximum allowable concentrations, effective sampling strategies increase the likelihood of detecting noncompliance. If data are highly autocorrelated or sharply seasonal in distribution, an exceedance-driven sampling strategy is more effective and efficient for detecting violations than fixed frequency sampling. However, data generated by exceedance-driven sampling provide biased estimates of mean and standard deviation. 相似文献
137.
推导了 BOD5稀释系数的量值关系 ,得出 BOD5稀释系数与样品的可生化性成正比 ,与稀释后水样的耗氧量成反比 ,并据此进一步分析了如何对样品的可生化性和稀释后水样的耗氧量进行预期。在此基础上从实际出发 ,根据工作经验简化和优化了稀释倍数的计算 ,达到提高测定准确度 ,降低劳动强度的目的 相似文献
138.
Spatial based compromise programming for multiple criteria decision making in land use planning 总被引:1,自引:0,他引:1
Sumbangan Baja David M. Chapman Deirdre Dragovich 《Environmental Modeling and Assessment》2007,12(3):171-184
Today, competing land use is continuing to occur in many developed regions. In the Agricultural Development Zone of Western
Sydney Region, which is characterised by complex landscape patterns, land use competition is widespread. From a land use planning
perspective, identification of suitable locations for a given type of land use is necessary for decision makers to formulate
land use alternatives in different locations, based on existing land potential and constraints. For such a region, use of
a simple method that implements a categorical system and considers only inherent land characteristics in the analysis is often
inadequate to arrive at an optimal spatial decision. The primary aim of this paper is to develop spatial modelling procedures
for agricultural land suitability analysis using compromise programming (CoPr) and fuzzy set approach within a geographical
information systems (GIS) environment. Five main sets of spatial data for use as decision criteria were developed by using
fuzzy set methodology: a land suitability index (LSI) for maximising the land productivity objective; an erosion tolerance
index (ETI) for minimising the erosion risk objective; a runoff curve number (CN) for maximising the water discharge regulation
objective; an accessibility (RP) measure for maximising the land accessibility objective; and the proximity to water body
(WP) for minimising the water pollution objective. An L
p
-metric was used in the analysis utilising different strategies with representative indices ranging from a situation where
full tradeoff among criteria occurs to a noncompensatory condition. Different weighting combinations were also applied, and decision analysis was carried out by using values ranging
from 0 to 1.0, where 1.0 is considered as an ideal point. The CoPr model demonstrated in this paper yielded a promising result,
as several different techniques of sensitivity analysis show reasonably good results. Likewise, an overlay of that result
with the present land use/land cover indicates a good corresponding spatial matching between existing land use (orchard and
cultivated land), and the cells (land parcels) classified as the best in CoPr. The results are amenable to various map display
techniques, either using continuous values or by defining different cut off points in the data space within a raster GIS environment. 相似文献
139.
140.
Josiah Akinsanmi Gregory M. Perry 《Journal of the American Water Resources Association》2002,38(1):101-110
ABSTRACT: Traditional focus on reducing one environmental externality may cause another externality to increase. This article examines the environmental and economic costs of abating soil loss and (or) nitrate leaching through alternative optimal production systems in the nonirrigated farming systems of Northeastern Oregon. Models estimating soil loss and nitrate‐nitrogen leaching rates associated with current production processes, are linked to a Multi‐Objective Programming (MOP) model. The results show that site specific conditions influence the level of abatement expenditures and optimal production strategies to reduce soil loss and leaching rates. Moreover, while existing production strategies are effective in reducing soil loss at little cost, no strategies could be identified to reduce nitrate leaching rate on some soils. 相似文献