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221.
Christine L. Jocoy 《Journal of the American Water Resources Association》2000,36(4):811-821
ABSTRACT: Research on the condition of drinking water provision in the United States documents the inequitable financial impact of environmental regulations on small water systems (those serving 3,300 or fewer people). While a variety of federal and state financial assistance programs are available for water systems, few quantitative analyses have evaluated the success of these programs in alleviating the problems of small systems. A case study of the largest aid initiative for water supply infrastructure in Pennsylvania provides the empirical framework through which to analyze government funding opportunities for water systems. This study examines the allocation practices of the Pennsylvania Infrastructure Investment Authority (PENNVEST) to water systems of varying sizes. Utilizing data from PENNVEST applications and the Pennsylvania Department of Environmental Protection, the distribution of PENNVEST award recipients and denied applicants by size characteristics are compared. The study indicates that very small water systems (those serving 500 or fewer) do not apply for or receive funds with the same frequency as their larger counterparts. Understanding the allocation of awards from PENNVEST offers insight into the ability of small communities to access capital for water supply infrastructure. 相似文献
222.
Patrick C. Mann John L. Mikesell 《Journal of the American Water Resources Association》1976,12(5):995-1004
ABSTRACT: Two types of organizational systems provide most of the water service in the United States. The investor-owned firm operates on a profit basis generally subject to state commission regulation. The government-owned firm is generally confronted by local control. The comparative efficiency of private versus government firm provision of water services is essentially an empirical issue. Unit costs and other operating statistics are examined for water firms of each ownership form. The analysis shows that private firms tend to have higher operation costs than do government firms, possibly attributable to wage-salary differentials. The analysis also indicates that capital investment in large government firms may result in diseconomies. The analysis creates serious doubt as to whether efficient provision of water services can be better facilitated by large mergers of either ownership form. 相似文献
223.
Across the globe, groups are experimenting with initiatives to create alternatives to the dominant food system. What role might research play in helping to strengthen and multiply these initiatives? In this paper we discuss two research projects in Australia and the Philippines in which we have cultivated hybrid collectives of academic researchers, lay researchers and various non-human others with the intention of enacting community food economies. We feature three critical interactions in the “hybrid collective research method”: gathering, which brings together those who share concerns about community food economies; reassembling, in which material gathered is deliberatively rebundled to amplify particular insights; and translating, by which reassembled ideas are taken up by other collectives so they may continue to “do work”. We argue that in a climate-changing world, the hybrid collective research method fosters opportunities for a range of human and non-human participants to act in concert to build community food economies. 相似文献
224.
Destruction of Wetlands and Waterbird Populations by Dams and Irrigation on the Murrumbidgee River in Arid Australia 总被引:3,自引:0,他引:3
The Lowbidgee floodplain is the Murrumbidgee Rivers major wetland in southeastern Australia. From more than 300,000 ha in the early 1900s, at least 76.5% was destroyed (58%) or degraded (18%) by dams (26 major storages), subsequent diversions and floodplain development. Diversions of about 2,144,000 ML year–1 from the Murrumbidgee River come from a natural median flow of about 3,380,000 ML year–1 providing water for Australias capital, hydroelectricity, and 273,000 ha of irrigation. Diversions have reduced the amount of water reaching the Lowbidgee floodplain by at least 60%, from 1888 to 1998. About 97,000 ha of Lowbidgee wetland was destroyed by development of the floodplain for an irrigation area (1975–1998), including building of 394 km of channels and 2,145 km of levee banks. Over 19 years (1983–2001), waterbird numbers estimated during annual aerial surveys collapsed by 90%, from an average of 139,939 (1983–1986) to 14,170 (1998–2001). Similar declines occurred across all functional groups: piscivores (82%), herbivores (87%), ducks and small grebe species (90%), large wading birds (91%), and small wading birds (95%), indicating a similar decline in the aquatic biota that formed their food base. Numbers of species also declined significantly by 21%. The Lowbidgee floodplain is an example of the ecological consequences of water resource development. Yanga Nature Reserve, within the Lowbidgee floodplain, conserved for its floodplain vegetation communities, will lose these communities because of insufficient water. Until conservation policies adequately protect river flows to important wetland areas, examples such as the Lowbidgee will continue to occur around the world. 相似文献
225.
Douglas S. Kenney 《Journal of the American Water Resources Association》1999,35(3):493-503
ABSTRACT: The 1990s have featured a rapid proliferation of “watershed initiatives” in the western United States and elsewhere. Watershed initiatives are ad hoc, voluntary associations typically featuring both governmental and non-governmental actors organized together to collaboratively seek new strategies for addressing water and related natural resource problems at physically relevant regional scales. These efforts are a response to historical and sociopolitical trends that have resulted in increasingly ineffective forums and processes of resource management decision-making, and that have subordinated the role of local stakeholders in problem-solving efforts. In most cases, watershed initiatives appear to provide a pragmatic vehicle for resource managers and stakeholders to address common concerns in a more efficient manner than is otherwise possible, and as such, deserve further application and continued support. 相似文献
226.
227.
Richard S. Krannich Sean P. Keenan Michael S. Walker Donald L. Hardesty 《Journal of the American Water Resources Association》1995,31(5):851-865
ABSTRACT: Survey data collected in the San Joaquin Valley of southern California and the Grand Valley of western Colorado reveal that residents of both areas believe that a severe sustained drought is likely to occur within the next 20–25 years and that their communities would be seriously impacted by such an event. Although a severe sustained drought affecting the Colorado River Basin would cause major economic and social disruptions in these and other communities, residents express little support for water management alternatives that would require significant shifts in economic development activities or in water use and allocation patterns. In particular, residents of these areas express little support for strategies such as construction and growth moratoriums, mandatory water conservation programs, water transfers from low-to high-population areas, water marketing, or reallocations of water from agricultural to municipal/industrial uses. This rejection of water management strategies that would require a departure from “business as usual” with respect to water use and allocations severely restricts the capacity of these and similar communities to respond effectively should a severe sustained drought occur. 相似文献
228.
河豚毒素检测技术研究进展 总被引:2,自引:0,他引:2
对检测河豚毒素的主要方法包括生物检测方法、理化检测方法、免疫学方法、传感器方法进行了介绍,并对目前检测方法的优缺点进行比较分析。小鼠测定法是河豚毒素检测的标准方法;理化检测法方法准确,但是对设备要求高,前处理严格;免疫学方法费用较高;传感器方法是新方法,还有待进一步规范。各种检测方法都有其优缺点,河豚毒素检测时应根据要求选择方法。 相似文献
229.
Joseph W. Dellapenna 《Journal of the American Water Resources Association》1994,30(2):197-204
ABSTRACT: Lawyers, engineers, and hydrologists are accustomed to thinking of water law as falling into one of two incompatible models: riparian rights (under which water is allocated by courts according to the relative reasonableness of the competing uses) and appropriative rights (under which water is allocated according to the temporal priority of the competing uses, largely by the action of the water users themselves but perfected by the issuance of an administrative permit). Usually unnoticed is the existence of a third approach, which I have dubbed “regulated riparianism.” Under regulated riparianism, water is allocated by water permits issued after an administrative determination of the reasonableness of the proposed use before the use is commenced. This system, now in place in about half of the states east of Kansas City (plus Hawaii), thus is fundamentally different from either the traditional ripanan rights that it replaces or the appropriative rights found in western states. 相似文献
230.
本文简述了我国《地表水环境质量标准》中分析方法已不适应现代分析技术的发展,归纳总结了地表水中无机元素和有机物污染物的最新分析方法。通过整合优化,分析地表水109项指标由原来的80余种精简至32种方法。 相似文献