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61.
Donna M. Cosgrove Gary S. Johnson 《Journal of the American Water Resources Association》2004,40(6):1469-1482
ABSTRACT: Increasing demands on western water are causing a mounting need for the conjunctive management of surface water and ground water resources. Under western water law, the senior water rights holder has priority over the junior water rights holder in times of water shortage. Water managers have been reluctant to conjunctively manage surface water and ground water resources because of the difficulty of quantification of the impacts to surface water resources from ground water stresses. Impacts from ground water use can take years to propagate through an aquifer system. Prediction of the degree of impact to surface water resources over time and the spatial distribution of impacts is very difficult. Response functions mathematically describe the relationship between a unit ground water stress applied at a specific location and stream depletion or aquifer water level change elsewhere in the system. Response functions can be used to help quantify the spatial and temporal impacts to surface water resources caused by ground water pumping. This paper describes the theory of response functions and presents an application of transient response functions in the Snake River Plain, Idaho. Transient response functions can be used to facilitate the conjunctive management of surface and ground water not only in the eastern Snake River Plain basin, but also in similar basins throughout the western United States. 相似文献
62.
环境政策作用机制的分析框架 总被引:1,自引:0,他引:1
了解环境政策作用机制是环境政策有效调控的前提和核心,准确理解环境政策作用的背景、成因、过程、作用机制、效应动态、演变规律等;全面而深刻地环境政策副作用和变形的生成-演变规律,了解政策副作用形成机制、传导机制、积累发展机制、作用机制、研究政策变形对环境政策适应性和效率的影响才可能准确预测环境政策所引发的变化,这些变化对社会经济的影响,进而对环境政策的反馈影响和反馈作用,才可能准确有效地设计开发政策工具和调控机制,有铲地进行环境政策调控,提高环境政策的预见性、准确性、操作性和适应性。 相似文献
63.
Dalia Streimikiene 《Natural resources forum》2005,29(4):322-333
This article summarizes some of the results from the application of the indicators for sustainable energy development (ISED) tool for analyzing Lithuania's energy sector, in terms of trends, setting energy policy goals and monitoring progress towards these goals. This experience illustrates the potential applicability of the ISED methodology for energy policy development in economies in transition, using Lithuania as an example. The article presents a summary of the results achieved and conclusions arrived at from the analysis of six priority areas in the context of the research project coordinated by the International Atomic Energy Agency, and provides recommendations for the development of sustainable energy policy using the ISED approach. 相似文献
64.
John V. Westra Julie K.H. Zimmerman Bruce Vondracek 《Journal of the American Water Resources Association》2005,41(2):309-322
ABSTRACT: Farmers can generate environmental benefits (improved water quality and fisheries and wildlife habitat), but they may not be able to quantify them. Furthermore, farmers may reduce their incomes from managing lands to produce these positive externalities but receive little monetary compensation in return. This study simulated the relationship between agricultural practices, water quality, fish responses to suspended sediment and farm income within two small watersheds, one of a cool water stream and one of a warm water stream. Using the Agricultural Drainage and Pesticide Transport (ADAPT) model, this study related best management practices (BMPs) to calculated instream suspended sediment concentrations by estimating sediment delivery, runoff, base flow, and streambank erosion to quantify the effects of suspended sediment exposure on fish communities. By implementing selected BMPs in each watershed, annual net farm income declined $18,000 to $28,000 (1 to 3 percent) from previous levels. “Lethal” fish events from suspended sediments in the cool water watershed decreased by 60 percent as conservation tillage and riparian buffers increased. Despite reducing suspended sediments by 25 percent, BMPs in the warm water watershed did not reduce the negative response of the fisheries. Differences in responses (physical and biological) between watersheds highlight potential gains in economic efficiency by targeting BMPs or by offering performance based “green payments.” 相似文献
65.
Yongsung Cho K. William. Easter Laura M.J. McCann Frances Homans 《Journal of the American Water Resources Association》2005,41(3):729-740
ABSTRACT: The concentrations of iron and sulfate in community water supplies are a concern for a number of areas in southwestern Minnesota. This study used the contingent valuation method to determine how much consumers would be willing to pay to improve their drinking water quality. On average, individuals were willing to pay US$5.25 per month (in 1995 U.S. dollars) to reduce the level of iron and US$4.33 per month to reduce the level of sulfate in their water to the USEPA's secondary standards for drinking water quality. Respondents with negative perceptions of their drinking water quality were willing to pay more to improve water quality. The aggregate annual willingness to pay (WTP) for all consumers in community water systems in southwestern Minnesota that were out of compliance with water quality standards were estimated to be US$2.4 million and US$2.0 million (in 1995 dollars) for reducing the levels of iron and sulfate, respectively. Yet the total WTP of consumers who use small community water systems may not be enough to pay the full cost of providing improved water in those systems. Economies of scale in water treatment and difficulties in financing improvements mean that technical innovation, government assistance, or institutional changes may be needed to improve water quality in these areas. 相似文献
66.
从"单独二孩"政策到"全面放开二孩"政策,政府针对中国人口现实情况不断做出符合社会需求的政策调整,尽管有可能缓解长期以来计划生育政策导致的适龄劳动力短缺及"未富先老"等社会问题,但人口政策调整的长期效果却有待验证。为此,本文运用灰色预测模型和Leslis模型等方法,对"全面放开二孩"生育政策背景下中国未来人口出生率的冲击和波动趋势作出预测,并对"全面放开二孩"政策所带来的对生育率及人口年龄结构影响展开分析,对2016—2050年的出生率、人口总数及人口结构作出预测,最终发现"全面放开二孩"政策会促进人口结构相对优化,但不能从根本上扭转劳动力供求关系失衡和老龄化加剧的趋势。为防止落入人口超低生育率陷阱,适度抑制老龄化快速增长趋势,实现人口与社会经济全面协调发展,必须对现行的生育政策进行完善,短期内,应积极出台配套措施,全面贯彻"全面放开二孩"政策,积极应对老龄化趋势;长期内,应逐步过渡到自主生育政策,形成人口自然生长的均衡发展长效机制。 相似文献
67.
Green radicalism among local environmental officials in Sweden is examined with the aims of theoretically elaborating on different dimensions of Green radicalism in the context of public administration, exploring the dimensionality of Green radicalism among officials, and examining the extent to which Green radicalism is associated with policy influence. Three types of Green radicalism are identified: Green ethics, Green institutional change, and Green activism. Survey data (N = 701) show that the three theoretical dimensions are present among officials, and that there is no negative association between radicalism and influence. It is primarily officials with Green activism beliefs who perceive themselves as able to influence policy. These findings suggest a need for more nuanced understanding of and further studies into the role of public administration in the quest for more radical Green reforms. 相似文献
68.
ABSTRACTThis paper assesses the evolution of generation technology-mix in Australia, with specific emphasis on understanding how such evolution has been shaped by wider political and socio-economic influences. This assessment is predicated on the argument that the contemporary, quintessentially techno-economic, policy discourse on renewable energy is deficient, as it ignores climacteric political and socio-economic influences on generation technology-mix. The methodological framework employed in this paper is informed by the core tenets of technological change theory. The assessment suggests that generation technology-mix in Australia has historically been overwhelmingly influenced by the underlying technological paradigm of the electricity industry; and that this technological paradigm essentially draws its imprimatur from the wider political and socio-economic contexts. By implication, it suggests that a rapid uptake of renewables will have widespread ramifications, extending into political, socio-economic and cultural realms of a society. Clearly, existing policy discourse – that tends to focus on technical potentials, cost competitiveness, externalities and risks of various renewable technologies – is deficient. A much broader discourse is needed. This paper also made an attempt to develop a basis for such a discourse by reviewing broader aspects of the Australian society that would be affected by a rapid uptake of renewables. 相似文献
69.
70.
A survey-embedded experiment implemented around the time of the 2014 annual Conference of the Parties (COP) to the United Nations Framework Convention on Climate Change (N ≈ 1200) examined whether such summits are able to increase citizens’ awareness of climate problems. This study finds that exposure to positive or negative cues about the COP increases climate change awareness, particularly among participants who start out with a low level of awareness. Neither positive nor negative cues about the COP significantly affect people’s policy preferences. Our finding resonates with Bernard Cohen’s observation that the mass media may not often be successful in telling people what to think, but they are successful in telling readers what to think about. 相似文献