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821.
ABSTRACT: Integrated watershed management in the Lower Mississippi Alluvial Plain (Delta) requires blending federal, state, and local authority. The federal government has preeminent authority over interstate navigable waters. Conversely, state and local governments have authority vital for comprehensive watershed management. In the Delta, integrating three broad legal and administrative regimes: (1) flood control, (2) agricultural watershed management, and (3) natural resources and environmental management, is vital for comprehensive intrastate watershed, and interstate river basin management. Federal Mississippi River flood control projects incorporated previous state and local efforts. Similarly, federal agricultural programs in the River's tributary headwaters adopted watershed management and were integrated into flood control efforts. These legal and administrative regimes implement national policy largely in cooperation with and through technical and financial assistance to local agencies such as levee commissions and soil and water conservation districts. This administrative infrastructure could address new national concerns such as nonpoint source pollution which require a watershed scale management approach. However, the natural resources and environmental management regime lacks a local administrative infrastructure. Many governmental and non governmental coordinating organizations have recently formed to address this shortcoming in the Delta. With federal and state leadership and support, these organizations could provide mechanisms to better integrate natural resources and environmental issues into the Delta's existing local administrative infrastructure.  相似文献   
822.
In this perspective, we reflect upon the question: what processes may help transition scientific insights on sustainability issues into practice and thus contribute to tackling the complex, systemic sustainability problems of today? We use five forerunners in the field of providing and brokering knowledge for science informed real world solutions, all published in Ambio and highlighted in this Anniversary collection, as our starting point. We discuss how the authors present solutions, whom they tried to reach, and what was suggested—implicitly or explicitly—as the potential uptake processes for turning scientific knowledge into practice. With this as the starting point, we discuss how sustainability science, as a field vowed to action, has evolved in its views of actors, pathways for impacts, and the potential roles of research and researchers to promote sustainability transformations.  相似文献   
823.
ABSTRACT: The Montana Department of Natural Resources and Conservation developed a hydrologic model to help analyze the effects of allocating water for consumptive and instream uses in the upper Missouri River basin of Montana. The model, a PC-based FORTRAN program, uses a mass-balance approach to compute monthly streamflows, reservoir operations, hydropower production, and irrigation and municipal water uses throughout the 54,000 square mile basin for a 59-year base period. Simulation results are presented as monthly mean and percentile-exceedence values. The model was run for baseline conditions and six hypothetical water-allocation alternatives. Results were used by staff resource area specialists to assess potential impacts to water quantity and distribution, water rights, water quality, stream channel form, fisheries, wildlife, recreation, hydropower production, and economics. These analyses were presented to the public and the decision-making board in an environmental impact statement (EIS). Though, in many instances, the model did not allow for detailed, site-specific analyses, the model was an important tool and its simulation results formed the hydrologic basis for the EIS.  相似文献   
824.
生态现代化理论与中国当前的环境决策   总被引:5,自引:0,他引:5  
生态现代化在理解和阐释现代工业社会如何应付环境危机的过程中,逐渐成为社会科学的一种主导理论,对当前中国而言这一理论同样适用。本文阐述了生态现代化的发展历程和主要内容,然后结合中国的实际,将生态现代化理论应用于分析目前国内已有的某些决策,指明当前迫在眉睫的工业环境改良、产业重构方向。最后用生态现代化的观点和方法构想中国当前的环境决策方法,以促进经济和环境的协调发展。  相似文献   
825.
以碳捕集与封存为典型的新兴技术在应对气候变化上的降碳功能显著,但该技术颇具不确定性。“决策于未知”成为政府规制技术风险的真实写照,如何在鼓励碳捕集与封存技术发展,助力“双碳”目标实现的同时,应对随之而来的风险挑战与安全诉求,既是国家必须肩负的义务,也是回应公众期待的内在要求。应运而生的风险预防原则作为应对气候变化的重要举措,为技术风险规制提供了合法性与正当性基础,对于碳捕获、封存技术发展与碳中和目标实现具有重要现实意义。为此,风险预防原则在技术规制中,应当整体遵循弱风险预防理念,彰显秩序、正义和效率的多元价值诉求,实现科学理性与社会理性的平衡。在此基础上,通过多手段的综合应用,开放的风险决策结构,强化风险管理的动态调试,以预防性环境行政公益诉讼为保障,将风险预防原则融汇于碳捕集与封存技术风险规制中。  相似文献   
826.
Fish habitat loss has been prevalent over the last century in Canada. To prevent further erosion of the resource base and ensure sustainable development, Fisheries and Oceans Canada enacted the habitat provisions of the Fisheries Act in 1976. In 1986, this was articulated by a policy that a “harmful alteration, disruption, or destruction to fish habitat” (HADD) cannot occur unless authorised with legally binding compensatory habitat to offset the HADD. Despite Canada’s progressive conservation policies, the effectiveness of compensation habitat in replicating ecosystem function has never been tested on a national scale. The effectiveness of habitat compensation projects in achieving no net loss of habitat productivity (NNL) was evaluated at 16 sites across Canada. Periphyton biomass, invertebrate density, fish biomass, and riparian vegetation density were used as indicators of habitat productivity. Approximately 63% of projects resulted in net losses in habitat productivity. These projects were characterised by mean compensation ratios (area gain:area loss) of 0.7:1. Twenty-five percent of projects achieved NNL and 12% of projects achieved a net gain in habitat productivity. These projects were characterised by mean ratios of 1.1:1 and 4.8:1, respectively. We demonstrated that artificially increasing ratios to 2:1 was not sufficient to achieve NNL for all projects. The ability to replicate ecosystem function is clearly limited. Improvements in both compensation science and institutional approaches are recommended to achieve Canada’s conservation goal.  相似文献   
827.
Ten Key Questions About the Management of Water in the Yellow River Basin   总被引:3,自引:0,他引:3  
Water is scarce in many regions of the world, clean water is difficult to find in most developing countries, there are conflicts between irrigation needs and urban demands, and there is wide debate over appropriate means of resolving these problems. Similarly, in China, there is limited understanding of the ways in which people, groups, and institutions contribute to, are affected by, and respond to changes in water quantity and quality. We use the example of the Yellow River basin to argue that these social, managerial, and policy dimensions of the present water problems are significant and overshadow the physical ones. Despite this, they receive relatively little attention in the research agenda, particularly of the lead agencies in the management of the Yellow River basin. To this end, we ask ten research questions needed to address the policy needs of water management in the basin, split into two groups of five. The first five relate to the importance of water in this basin and the changes that have affected water problems and will continue to do so. The second five questions represent an attempt to explore possible solutions to these problems.  相似文献   
828.
In this study, an interval-parameter two-stage mixed integer linear programming (ITMILP) model is developed for supporting long-term planning of waste management activities in the City of Regina. In the ITMILP, both two-stage stochastic programming and interval linear programming are introduced into a general mixed integer linear programming framework. Uncertainties expressed as not only probability density functions but also discrete intervals can be reflected. The model can help tackle the dynamic, interactive and uncertain characteristics of the solid waste management system in the City, and can address issues concerning plans for cost-effective waste diversion and landfill prolongation. Three scenarios are considered based on different waste management policies. The results indicate that reasonable solutions have been generated. They are valuable for supporting the adjustment or justification of the existing waste flow allocation patterns, the long-term capacity planning of the City's waste management system, and the formulation of local policies and regulations regarding waste generation and management.  相似文献   
829.
Fenton试剂作为一种具有强氧化性的试剂,广泛地应用于废水处理的研究中.通过正交实验对Fenton试剂处理废水的几种影响因素进行了讨论,得出了影响因素的次序:Fe2 的投加量>H2O2的投加量>pH值>反应时间.同时得到Fenton试剂处理造纸废水的最佳工艺条件:pH=5.0,FeSO4·7H2O的投加量为5.93g/L,H2O2的投加量为8.8‰(体积百分比),搅拌时间0.5 h,COD值由原来的2167 mg/L降至187 mg/L,COD去除率达到91.37%.  相似文献   
830.
用政策作指导以法律为依据提高环境评价质量   总被引:1,自引:0,他引:1  
谭祥炳 《四川环境》2000,19(2):73-75
本文提出了环境影响评价必须用政策作指导 ,以法律为依据 ,提高环境影响评价质量的几点意见。  相似文献   
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