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51.
ABSTRACT: Because of its importance and the perceived inability of private sector sources to meet water demands, many countries have depended on the public sector to provide water services for their populations. Yet this has resulted in many inefficient public water projects and in inadequate supplies of good quality and reliable water. Decentralization of water management, including the use of water markets, cannot solve all of these water problems, but it can improve the efficiency of water allocation. When given adequate responsibility and authority, water user associations have effectively taken over water management activities at a savings to tax payers. Moreover, water markets add the potential benefit of improving water efficiency within a sector as well as providing a mechanism for reallocating water among sectors. The key question involves developing innovative mechanisms for reducing the transaction costs of organizing water users and of making water trades. Water rights need to be established which are recorded, tradable, enforceable, and separate from land if markets are to operate effectively. Also, institutions are needed that effectively resolve conflicts over water rights, including third party impacts and water quality concerns. 相似文献
52.
Kathryn Paxton George 《Journal of Agricultural and Environmental Ethics》1992,5(2):217-233
In response to Evelyn Pluhar'sWho Can Be Morally Obligated to Be a Vegetarian? in this journal issue, the author has read all of Pluhar's citations for the accuracy of her claims and had these read by an independent nutritionist. Detailed analysis of Pluhar's argument shows that she attempts to make her case by consistent misappropriation of the findings and conclusions of the studies she cites. Pluhar makes sweeping generalizations from scanty data, ignores causal explanations given by scientists, equates hypothesis with fact, draws false cause conclusions from studies, and in one case claims a conclusion opposite of what the scientist published. Such poor reasoning cannot be the basis of an argument for moral vegetarianism. A broader search of the literature and attention to reviews and textbooks in nutrition shows that each of Pluhar's claims is suspect or incorrect. Pluhar has not undermined my central claims: even if animals have certain rights and well-planned vegetarian diets are safe in complex industrialized societies, these diets cannot be so regarded if the presuppositions of high levels of wealth, education, and medical care do not exist; and, women, children, the aged and some ill persons are at greater risk on restrictive vegan diets. Thus, any duty of moral vegetarianism is not categorical but provisional in nature. 相似文献
53.
城市土地资产经营新思路探讨 总被引:5,自引:0,他引:5
康雄华 《中国人口.资源与环境》2003,13(4):60-63
自1996年上海市成立第一家土地收购储备机构——土地发展中心后,全国各大城市已纷纷效仿它的成功经验。截止2001年8月不完全统计,全国已有大小不同的土地收购储备机构669家。实践证明,土地收购储备机制在盘活城市存量土地,促进土地集约利用,保障城市土地资产的保值增值等方面成绩卓著。然而,实践过程中,土地收购储备机制的运作也暴露出不少问题。本文通过对这些问题的分析,提出了引进公司制度完善土地收购储备机制,合理运营城市土地资产的新思路。 相似文献
54.
55.
Land Conversion for Suburban Housing: A Study of Urbanization Around Warsaw and Olsztyn,Poland 总被引:9,自引:0,他引:9
In Poland of the 1990s, urban demand for housing land around city agglomerations increased rapidly. The decreasing profitability of agricultural production also caused farmers to become interested in the sale of agricultural land for nonagricultural purposes, and new land legislation granted them the right to sell their land. Polish counties simultaneously received self-governing status, which allowed them to define the priorities for local development. Counties received additional responsibility for land management and quickly demonstrated strong support for land conversion, which was perceived as a factor of local development. This paper argues that decentralization and the extension of private control over land have led to a loss of rural landscapes in Poland because farmers, county governments, and rural society in general gained from the conversion of agricultural to housing land. Rapid urbanization has significantly reduced the availability of open space around cities and threatened valuable landscapes, for it has occurred in the absence of environmental safeguards. This paper reports findings from research in two counties, located in regions with diverse economic growth rates. Decentralization is particularly problematic if tax regulations and intergovernmental fiscal relations reward local authorities for urbanization but not environmental protection.
Note: This version was published online in June 2005 with the cover date of August 2004. 相似文献
56.
黄腐酸的萃取和性质研究 总被引:3,自引:0,他引:3
黄腐酸是腐植酸中最具活力的组成部分,蕴藏量丰富,萃取方法简便。研究了从红原1#泥炭中萃取黄腐酸和降解物。它的分子量较小,易溶于水,抗絮凝性能好,分子内含有较多的活性官能团,具有很高的化学活性和生物活性,用途广泛。 相似文献
57.
William E. Cox Keith A. Argow 《Journal of the American Water Resources Association》1979,15(3):728-739
ABSTRACT: The issues involved in the conflict between the rights of the public and those of riparian landowners are examined by reviewing the public access situation with regard to inland streams in the State of Virginia. Consideration is given to the legal framework defining access rights and to the attitudes of riparian landowners regarding the access question. Existing provisions of law suggest only limited recognition of public rights, but this law is incompletely developed. A considerably broader concept of public rights could be developed within the existing framework due to the existence of unresolved questions. The analysis of landowner attitudes is based on a survey of a sample of riparian owners chosen from throughout the state. The questionnaire used in the survey contained 123 questions in a variety of areas, including landowners' perceptions of public rights, problems encountered as the result of recreational water use, attitudes toward state designation and protection of scenic rivers, and the acceptability of alternatives for increasing public access. Although the survey results indicate substantial acceptance of the concept of public use, the landowners expressed concern over governmental control of land use and did not indicate a generally acceptable means for increasing public use. 相似文献
58.
Marion Babcock Bruce Mitchell 《Journal of the American Water Resources Association》1980,16(3):532-537
ABSTRACT: This study is an examination of the relationship between flooding and property values for an urban community in southwestern Ontario which has a lengthy history of flooding. As well, peoples’perceptions of the effect of flooding on property values is discussed. Analysis of sales prices and assessment data demonstrated no statistically significant differences in values of property for residences located in high- and low-risk areas either before or after a major flood in 1974. With both the high- and low-risk areas, sales prices after the 1974 flood were significantly higher than sales prices before the flood. The perceived property values followed a similar pattern. We concluded that differences in flood risk and flood experience did not adversely affect actual or perceived long-term property values. 相似文献
59.
Otis W. Tempter 《Journal of the American Water Resources Association》1981,17(5):789-798
Texas' surface water law began its evolution during the Hispanic period of occupance. Later, the English riparian doctrine was adopted, and finally, in the late 1800's, the prior appropriation doctrine was superimposed, resulting in an exceedingly complex dual system. Though the judiciary, legislature, and state water agencies have wrestled with the problem of coordinating these diverse water rights and more accurately delineating and measuring riparian rights and water use since early in this century, until recently all attempts were unsuccessful. The unknown riparian element, in particular, made coordinated and efficient management and administration of the state's surface water resources impossible. Finally, measurable progress toward solution of these problems began in 1967 with passage of the Water Rights Adjudication Act, aimed at identifying all unrecorded surface water rights claims and eventually merging all claims into the permit system. This paper examines the gradual evolution of Texas' curious blend of Hispanic-English riparian rights and later appropriate rights; discusses the resultant problems of water resource administration; and traces the progress of the ongoing water rights adjudication, a lengthy, expensive, and complex procedure, which should eventually make possible more efficient administration of all surface water rights. 相似文献
60.
Herbert W. Greydanus 《Journal of the American Water Resources Association》1978,14(2):477-480
ABSTRACT: Most of California's precipitation falls at the wrong place in the wrong season in relation to the water needs. Redistribution and regulation are essential. Aquifer systems – groundwater basins – can provide a share of the future cyclic storage regulation. There are some differences in management concepts in using a full basin in comparison with a partially dewatered basin. Legal, water quality, and physical impacts on aquifer systems, including subsidence, are concerns. Storage may be for the benefit of overlying water users or for distant areas. Extraction during dry periods or recharge methods will require careful planning. Existing rights and uses and equitable treatment of all parties must be assured. Financial compensation may be involved. Changes in methods of operation or degree of self-determination by affected water agencies will require committed watermanship to resolve. Legislation or amendments to organic acts may be needed but much can be accomplished within existing statutes. Environmental impacts which can be avoided by not using large surface storage sites are important. Energy for pumping will be a key consideration. About 40 percent of California is underlain by aquifer systems. This resource offers major potential in overcoming the maldistribution of natural water resources. 相似文献