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131.
John H. Martin 《Journal of the American Water Resources Association》1997,33(4):741-753
ABSTRACT: On May 19, 1993, a jury in the U.S. District Court for the Western District of New York found Southview Farm and Richard H. Popp guilty of violating the Clean Water Act on five occasions. The violations were the result of storm water runoff from a site used for disposal of dairy cattle manure from an unpermitted concentrated animal feeding operation. The presiding District Court judge later dismissed the jury verdict, and subsequently a U.S. Court of Appeals for the Second Circuit reversed the dismissal. The Court of Appeals concluded that the discharges were not exempt as agricultural storm water discharges, and that the manure spreaders involved were point sources. Because the use of animal manures in crop production activities will result, unavoidably, in the discharge of some pollutants to adjacent surface waters, a rational and universally applicable basis is needed to determine when such discharges are point versus nonpoint source. Current statutes and regulations do not delineate clearly such a boundary. To address this lack of specificity, I propose that application rates be based on recommended crop nutrient needs. 相似文献
132.
Hugo A. Loaiciga Stephen Renehan 《Journal of the American Water Resources Association》1997,33(6):1313-1326
ABSTRACT: This paper synthesizes and interprets data pertaining to the evolution of average water revenue, water use, and the average cost of water supply in the City of Santa Barbara, California, from 1986 to 1996, a period which included one of the most devastating droughts in California this century. The 1987–1992 drought hit the study area particularly hard. The City of Santa Barbara was dependent exclusively on local sources for its water supply. That made it vulnerable as the regional climate is prone to extreme variability and recurrent droughts. The 1986–1992 drought provided a rare opportunity to assess the sensitivity of municipal water use to pricing, conservation, and other water management measures under extreme drought conditions. Our analysis indicates that the average cost of water rose more than three-fold in real terms from 1986 to 1996, while the gap between the average cost of supply and the average revenue per unit of water (= 100 cubic feet) rose in real terms from $0.14 in 1986 to $ 0.75 in 1996. The rise of $3.08 in the average cost of supplying one unit of water between 1986 and 1996 measures the cost of hedging drought risk in the study area. Water use dropped 46 percent at the height of the drought relative to pro-drought water use, and remains at 61 percent of the pre-drought level. The data derived from the 1987–1992 California drought are unique and valuable insofar as shedding light on drought/water demand adaptive interactions. The experience garnered on drought management during that unique period points to the possibilities available for future water management in the Arid West where dwindling water supplies and burgeoning populations are facts that we must deal with. 相似文献
133.
Adaptive management: Promises and pitfalls 总被引:3,自引:1,他引:3
Proponents of the scientific adaptive management approach argue that it increases knowledge acquisition rates, enhances information flow among policy actors, and provides opportunities for creating shared understandings. However, evidence from efforts to implement the approach in New Brunswick, British Columbia, Canada, and the Columbia River Basin indicates that these promises have not been met. The data show that scientific adaptive management relies excessively on the use of linear systems models, discounts nonscientific forms of knowledge, and pays inadequate attention to policy processes that promote the development of shared understandings among diverse stakeholders. To be effective, new adaptive management efforts will need to incorporate knowledge from multiple sources, make use of multiple systems models, and support new forms of cooperation among stakeholders. 相似文献
134.
菹草的经济价值及其栽培与养鱼技术 总被引:12,自引:0,他引:12
菹草是渔业水域生态系统中的初级生产者,为渔业生产的重要自然资源之一、根据近年来的试验研究成果,本文探讨了菹草的自明、药用、饲用价值及其在渔业水域中对自然国类资原的增殖与保护作用,介绍了菹草人工栽培与养鱼的技术措施。 相似文献
135.
Allan K Fitzsimmons 《Journal of the American Water Resources Association》1996,32(2):217-227
ABSTRACT: Protection of ecosystems as entities on the landscape has attracted a wide range of support. Ecosystem-based public policies are claimed to be more effective, efficient, and scientifically sound than other approaches to environmental and natural resource policy. The ecosystem concept was never intended to serve as a public policy guide or to determine landscape units for land management purposes. This paper critically examines the use of the ecosystem concept in public policy and land use management and analyzes the proposed rule to manage the National Forest System according to ecosystem management principles. The concept is found to be unsuitable as a basis for guiding environmental and natural resource public policies in general while the proposed rule to manage the national forests according to ecosystem management principles is shown to be incoherent. 相似文献
136.
Frank A. Ward Thomas P Lynch 《Journal of the American Water Resources Association》1996,32(6):1127-1138
ABSTRACT: This paper presents an integrated optimal control model that optimizes economic performance of reservoir management in watersheds in which there are significant economic and hydrologic interdependencies. The model is solved using the General Algebraic Modeling System (GAMS). Results show that application of this model to New Mexico's Rio Chama basin can increase total system benefits over historical benefits by exploiting complementarities between hydroelectricity production, instream recreation, and downstream lake recreation. 相似文献
137.
138.
我国安全生产工作的体制、机制和自主创新的若干思考及建议 总被引:1,自引:7,他引:1
本文分析了安全生产工作的重要性和六个基本特点,总结了国内外安全生产的差距和面临的机遇与挑战,探讨了我国安全生产工作的体制、机制,并从专家的角度提出了一些战略性的建议。创新性地描述了由范围、对象、内容、目标和手段等组成的一个安全生产工作矩阵,并在此基础上探讨了安全科学技术与工程的发展思路与方法。从加强党和政府对安全生产工作领导迫切性的角度,扼要阐述了党和政府对安全生产工作领导的思考。 相似文献
139.
140.
进入“十一五”规划期,中国的大城市正面临着“建构资源节约型、环境友好型和谐社会”的重大战略转型。城市地下空间资源的综合开发利用是实现这一伟大战略目标的重要保障之一。作者在研究总结国外大城市地下空间资源综合开发利用成功经验与教训的基础上,分析未来中国城市发展趋势,论述城市地下空间资源综合开发利用的发展方向与战略目标,创造性的提出了实现这一伟大战略目标应该创建的中国式综合管理的体制、机制与法制。本文可供政府决策参考。 相似文献