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791.
Compensatory mitigation of impacted streams and wetlands has increased over the past two decades, with the associated industry spending over US$2.9 billion in aquatic restoration annually. Despite these expenditures, evaluations by the National Research Council and U.S. Government Accountability Office have provided evidence that compensatory mitigation practices are failing to protect aquatic resource functions and services, and vague federal policy and inadequate evaluation of compensatory mitigation projects are to blame. To address these weaknesses, an update to federal regulations on compensatory mitigation was released in 2008. Additionally, the 2012 Reissuance of Nationwide Permits, some of which affects compensatory stream mitigation, was recently published. Current policy, as reflected in these documents, still uses nonspecific language to direct compensatory stream mitigation leaving most implementation decisions to the local U.S. Army Corps of Engineers district. The majority of federal mitigation policy has focused on wetland compensation, with other aquatic resources receiving less attention (e.g., streams). In this article, weaknesses of current policy are discussed, as are suggested policy changes to minimize the loss of stream ecosystem functions and services. Compensatory mitigation policy should clearly define key terms, incorporate adaptive management procedures, and provide guidelines for determining mitigation costs and compensation ratio requirements.  相似文献   
792.
Urine diversion (UD) has great potential to contribute to sustainably managing wastewater by separating urine at the source and recovering nutrients for reuse in agriculture. While factors enabling the UD technology in Sweden are thought to involve policies supporting nutrient recovery/reuse, on closer inspection, the variable success of UD systems has revealed that critical factors for success also relate to human-centred issues of social organisation, participation and incorporation of social knowledges of a variety of stakeholders into the decision-making process in which new technologies are trialled and adopted. Through the analytical lens of strategic niche management, we consider how early experimentation in UD has involved user participation and whether internal processes of learning, networking and visioning have been consciously considered and to what effect. As niche experiments are enabled/disabled not only by informal institutions such as values and social norms but also formal regulatory institutions, we have concurrently analysed the broader environment in which policies and institutions influence, to varying degrees, the uptake of UD.  相似文献   
793.
Moving towards a more sustainable adaptation process requires closer integration of policies related to the environment. An important actor in this is the local government. This paper examines to what extend adaptation is currently being integrated into Dutch local policies, and what the role is of a municipality's size, risk and experience in the encountered manifestations of adaptation. First, it was determined that adaptations taking place only anticipate currently perceivable weather extremes – mostly increasing precipitation. Second, it was determined that the realisation of further adaptations is hindered by a strongly sectoral divided reality. Adaptation is now heavily dominated by the water department, while spatial planning and the environment are only limitedly involved. Finally, it was observed that the contextual factor size proved to most important for horizontal policy integration, whereas the contextual factor extreme-weather experience was the most definite for the realisation of adaptations. We conclude that a more sustainable adaptation should first tackle the sectoral divides which requires administrative efforts, for example, professional training. These would preferably be initiated from a vertical direction.  相似文献   
794.
Abstract

Agricultural residues can be converted to methane-rich gas mixture. Anaerobic biomethane production is an effective process for conversion of a broad variety of agricultural residues to methane to substitute natural gas and medium calorific value gases. Methane generating bacteria (methanogens) and other microbes that help digest dying plants in anaerobic conditions. Agricultural solid residues (ASR) represent a potential energy resource if they can be properly and biologically converted to methane.  相似文献   
795.
Renewable energy can address rising demand for energy, environmental protection, energy security, and job creation. This paper assesses resource, economic, social, and political drivers for the adoption of renewable energy. Analysis of the data collected from over 100 interviews with utility managers reveals that production tax credits significantly influence the percent of renewable energy in a utility's portfolio. The availability of renewable energy resources, economic drivers, social influences, and political drivers such as renewable portfolio standards and government grants are not significant drivers. Understanding these drivers can help electric utilities, governments, and other stakeholders with their efforts to reap the benefits of renewable energy.  相似文献   
796.
ABSTRACT: Federal and state governments in the United States and Australia have come to play a key role in attempts to mitigate the impact of drought. Government actions have usually taken the form of loans and grants to individual citizens, businesses and municipalities experiencing the hardship of drought. Most of these actions have occurred in an environment of crisis management, rather than as a result of clearly stated policy objectives. Based on a review and evaluation of recent drought policy in the United States and Australia, recommendations are offered on ways to improve the United States’approach. A national drought plan is suggested as an efficient mechanism through which these recommendations could be implemented. States should also become more actively involved in drought assessment and response, but these actions must be coordinated with federal actions.  相似文献   
797.
The outcome of recent international climate negotiations suggests we are headed toward a more fragmented carbon market, with multiple emission trading and offset programs operating in parallel. To effectively harmonize and link across programs, it will be important to ensure that across offset programs and protocols that a “ton is a ton”. In this article, we consider how sample offsets projects in the U.S. carbon market are treated across protocols from five programs: the Clean Development Mechanism, Climate Action Reserve, Chicago Climate Exchange, Regional Greenhouse Gas Initiative, and the U.S. EPA's former program, Climate Leaders. We find that differences among protocols for landfill methane, manure management, and afforestation/reforestation project types in accounting boundary definitions, baseline setting methods, measurement rules, emission factors, and discounts lead to differences in offsets credited that are often significant (e.g. greater than 50%). We suggest opportunities for modification and harmonization of protocols that can improve offset quality and credibility and enhance prospects for future linking of trading units and systems.  相似文献   
798.
This paper has developed a two-sector model of forestry that gives some insights into the interactions of poverty, land tenure insecurity, economic growth, trade and deforestation in the context of the drylands of Africa. Externally, the model results show that the world demand for non-timber forestry products can lead to a win-win situation whereby both trade and environmental sustainability can be promoted. Monopolistic measures to control the supply of these products, for short-term price gains, are harmful economically and environmentally. By contrast, productivity-raising measures have a favourable impact on both the economy and the environment. Internally, the model results show that the growth of the rest of the economy has driven the economic growth of the forestry sector, but at the same time, its environmental degradation. Poverty and land tenure insecurity also contribute to this degradation. Fortunately, policies promoting basic needs satisfaction and property rights security are shown to be effective in mitigating environmental degradation in the forestry sector. The paper results contribute towards a more sustainable exploitation of forestry.Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
799.
论中国可再生能源发展机制   总被引:8,自引:0,他引:8  
中国可再生能源存在着成本高和市场狭小两大问题,要根本解决这两大问题必须制定新政策,形成新机制。中国的可再生能源政策的多目标性决定了新出台政策应该是一个政策体系,具体应包括目标机制、定价机制、交易机制、选择机制和补偿机制五种运行机制。  相似文献   
800.
Differences between the scientific and environmental policy communities regarding marine environmental protection strategies are discussed in the context of the nature and extent of scientific influence on marine environmental policy. Public perceptions of the nature and severity of marine pollution frequently differ from scientific assessments. the thesis of this paper is that the increasing influence of public perception on marine environmental protection policy is leading to the adoption of simplistic and unnecessarily extreme approaches to marine pollution prevention and to a reduced reliance on science. This trend is illustrated by some recent international developments and some suggestions are made towards enhancing the influence of science on marine protection policy.  相似文献   
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