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991.
Ronald A. Chadderton Robert G. Traver Jayaram N. Rao 《Journal of the American Water Resources Association》1992,28(6):1069-1076
ABSTRACT: This paper presents a study which used a standard, hydraulic computer model to generate detailed design information to support conflict analysis of a water resource use issue. As an extension of previous studies, the conflict analysis in this case included several scenarios for stability analysis - all of which reached the conclusion that compromising, shared access to the water resources available would result in the most benefits to society. This expected equilibrium outcome was found to maximize benefit-cost estimates. 相似文献
992.
Brenda DeZiel Lori Krider Brad Hansen Joseph Magner Bruce Wilson Geoff Kramer John Nieber 《Journal of the American Water Resources Association》2019,55(1):154-188
Water quality and stream habitat in agricultural watersheds are under greater scrutiny as hydrologic pathways are altered to increase crop production. Ditches have been traditionally constructed to remove water from agricultural lands. Little attention has been placed on alternative ditch designs that are more stable and provide greater habitat diversity for wildlife and aquatic species. In 2009, 1.89 km of a conventional drainage ditch in Mower County, Minnesota, was converted to a two‐stage ditch (TSD) with small, adjacent floodplains to mimic a natural system. Cross section surveys, conducted pre‐ and post‐construction, generally indicate a stable channel with minor adjustments over time. Vegetation surveys showed differences in species composition and biomass between the slopes and the benches, with changes ongoing. Longitudinal surveys demonstrated a 12‐fold increase in depth variability. Fish habitat quality improved with well‐sorted gravel riffles and deeper pool habitat. The biological response to improved habitat quality was investigated using a Fish Index of Biological Integrity (FIBI). Our results show higher FIBI scores post‐construction with scores more similar to natural streams. In summary, the TSD demonstrated improvements in riparian and instream habitat quality and fish communities, which showed greater fish species richness, higher percentages of gravel spawning fish, and better FIBI scores. This type of management tool could benefit ditches in other regions where gradient and geology allow. 相似文献
993.
994.
For a sustainable municipal sewage sludge management, not only the available technology, but also other parameters, such as policy regulations and socio-economic issues should be taken in account. In this study, the current status of both European and Greek Legislation on waste management, with a special insight in municipal sewage sludge, is presented. A SWOT analysis was further developed for comparison of pyrolysis with incineration and gasification and results are presented. Pyrolysis seems to be the optimal thermochemical treatment option compared to incineration and gasification. Sewage sludge pyrolysis is favorable for energy savings, material recovery and high added materials production, providing a ‘zero waste’ solution. Finally, identification of challenges and barriers for sewage sludge pyrolysis deployment in Greece was investigated. 相似文献
995.
公众参与在突发性环境污染事件风险管理中可以发挥重要作用。根据参与者在风险管理中的不同作用,将公众划分为个体公众、社会团体、专家学者、新闻媒体4个类型;从风险管理的3个阶段(预防与准备、应急响应、事故恢复)出发,对各阶段具体工作中所需要的公众参与者类型、参与内容及形式进行了探讨。该研究为突发性环境污染事件风险管理中的公众参与提供了一些新的思路和方法,对有效提高风险管理水平具有借鉴意义。 相似文献
996.
Importance of information on tillage practices in the modelling of environmental processes and in the use of environmental indicators 总被引:1,自引:0,他引:1
Tillage has been and will always be integral to crop production. Tillage can result in the degradation of soil, water, and air quality. Of all farm management practices, tillage may have the greatest impact on the environment. A wide variety of tillage equipment, practices and systems are available to farmers, providing opportunities to enhance environmental performance. These opportunities have made tillage a popular focus of environmental policies and programs such as environmental indicators for agriculture. This paper provides a very brief examination of the role of tillage in crop production, its effect on biophysical processes and, therefore, its impact on the environment. Models of biophysical processes are briefly examined to demonstrate the importance of tillage relative to other farm management practices and to demonstrate the detail of tillage data that these models can demand. The focus of this paper is an examination of the use of information on tillage in Canada's agri-environmental indicators initiative, National Agri-environmental Health Analysis and Reporting Program (NAHARP). Information on tillage is required for several of the indicators in NAHARP. The type of data used, its source, and its quality are discussed. Recommendations regarding the collection of tillage data and use of tillage information are presented. 相似文献
997.
针对我国环境保护行政管理存在的直线式管理、缺乏弹性等问题,将适应性管理的理论和方法引入环境管理领域,提出适应性环境管理的概念和管理模式,通过构建基于AHP(层次分析法)的适应性环境管理绩效评估体系,在环境管理中对各项任务进行跟踪管理和绩效评估,反馈于阶段性目标的制定,从而灵活调整工作方案,最大限度地降低环境管理中的不确定性,保证环境管理总目标的达成. 相似文献
998.
Risk assessment/management frameworks employed around the world to guide environmental decision-making were analyzed for their approaches to developing risk management objectives and the decision criteria necessary for environmental policy implementation. Frameworks from the Netherlands, the UK, Sweden, Australia/New Zealand, Canada, and the USA were considered. Progress in refining the scientific basis for risk assessment/management has been made, but there has been little parallel development in defining the mechanisms by which available scientific information may be used to define risk management goals or identify and select between management options using a priori decision criteria. The lack of detailed guidance on the setting and achievement of risk management goals that appropriately balance technical information and public input remains an important challenge to the use and practice of all risk assessment/management frameworks. 相似文献
999.
以云南省城市空气自动监测站质控考核为依据,对考核中发现的问题进行了详细分析,探讨如何做好空气自动监测质量管理。 相似文献
1000.
企业如何增强市场竞争能力 ,一直是当前企业管理的重要问题之一。就对外工程招标投标的重要竞争手段报价问题 ,提出采用先进的计算机技术 ,开发出快捷准确的自动报价决策支持系统 ,以提高企业在未来WTO环境中的竞争能力。 相似文献