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541.
贵州省水资源承载力的空间地域差异 总被引:3,自引:1,他引:2
水资源承载力是一个国家或地区可持续发展过程中各种自然资源承载力的重要组成部分,对一个国家或地区综合的发展和发展规模有至关重要的影响。由于水资源承载力是涉及到人口、社会经济发展以及资源环境在内的复杂巨系统,通过利用综合多种因素的状态空间法,从综合、宏观的角度来描述研究区域现实的承载状况,并对其进行定量化表示和分析。以贵州省为例,根据其具体情况,选取了9个指标构成评价指标体系,并对各指标运用反映客观赋权的熵值法进行权重的确定,然后通过状态空间法求算出贵州省现实的水资源承载状态值及其理想状态值。计算结果表明,贵州省目前的水资源承载状况总体上处于超载状态,但不同的地区又有所差异,表现出一定的空间地域性。根据贵州省水资源承载的现状值与理想值的比较,把整个贵州省水资源承载力划分为3种类型区:严重超载区、满载区及可载区。计算结果符合贵州省水资源实际情况,对贵州省水资源的可持续利用具有一定的现实指导意义。 相似文献
542.
Daniel H. Hoggan Kirk R. Kimball Jay M. Bagley 《Journal of the American Water Resources Association》1981,17(1):1-9
ABSTRACT: Dramatic changes in Utah's economy caused by urbanization, large scale energy developments, and other influences will significantly reorient water use patterns. Thus, state water management policies and programs which have evolved over many years should be reevaluated. Several factors have influenced Utah water project financing policy. Among these have been: 1) the prominence of agriculture in the settlement of Utah and the century following, 2) dry cycles and periodic severe droughts, 3) recurring periods of economic depression, and 4) allocation of Colorado River water among the basin states and Mexico, Three revolving funds have been established. The Revolving Construction Fund, created in 1947, provides money for irrigation projects; the Cities Water Loan Fund, created in 1975, provides money to communities for developing culinary systems and improving quality to meet the demands of exploding population growth; and the Water Resources Conservation and Development Fund, created in 1978, provides money for large scale multipurpose water projects costing $1 million or more. The justification for these financing programs seems to be a mixture of rectifying market imperfections and income redistribution. However, trends in the agricultural sector and the multipurpose nature of large scale projects now being funded suggest that earlier justifications may no longer be valid. Rigorous project evaluation procedures, lacking in the past, should be adopted. 相似文献
543.
M.Anwar H.Khan M.M.Nazmul Hoque S.Shamsul Alam M.J.Ashfold Graham Nickless Dudley E.Shallcross 《环境科学学报(英文版)》2011,23(1)
Night-time OH levels have been determined for UK urban surface environments using two methods,the decay and steady state approximation methods.Measurement data from the UK National Environmental Technology Centre archive for four urban sites(Bristol,Harwell,London Eltham and Edinburgh) over the time period of 1996 to 2000 have been used in this study.Three reactive alkenes,namely isoprene,1,3-butadiene and trans-2-pentene were chosen for the calculation of OH levels by the decay method.Hourly measurements o... 相似文献
544.
Peter Crabb 《Journal of the American Water Resources Association》1983,19(1):23-28
ABSTRACT: Australia's extremely limited water resources highlight the need for policy guidelines for management. During the 1970s, there was the gradual evolution of a national water resources policy, facilitated by a nationally agreed statement of objectives and culminating in a federal policy statement presented in 1979. However, the Australian constitution gives major responsibility for water resources to the states. Further, the federal policy statement seems to assume that each state has a water resources policy and that it accords with the nationally agreed objectives. This is not the case, and the practical management of Australia's water resources falls short of the principles set out in the policy document. The River Murray, the nation's major water resource, provides ample evidence of this fact. With very limited water resources, Australia urgently needs to reduce the disparity between principle and practice in their management. 相似文献
545.
Robert L. Vertrees 《Journal of the American Water Resources Association》1985,21(1):115-134
ABSTRACT: A matrix was developed of problems with the functional use of water resources (rows) and functions served by water resources research (columns). A classification of water problems and a classification of research fields also were developed to accompany the matrix. The matrix and classification schemes were used when preparing the five-year research and development plan of the Water Resources Center of The Ohio State University. They were used: (1) to classify each research project that had been supported by the Water Resources Center from 1965 through 1980, (2) to guide interviews with personnel of federal and state agencies and university faculty who assisted in defining Ohio's water research needs, (3) to organize responses received during these interviews, and (4) to arrive at a selected list of ten problems with the functional use of Ohio's water resources that were prioritized based upon opinions received from water-related officials throughout the state. Other matrices and classification schemes are reviewed that were revised and expanded upon when formulating the ones used in Ohio. Suggestions are given regarding further development of the functional matrix and accompanying classifications as well as their use in administration of the cooperative federal-state water resources research program and other federal water resources research programs. 相似文献
546.
Daniel H. Hoggan 《Journal of the American Water Resources Association》1972,8(3):625-630
ABSTRACT As availability of funds in the federal budget for water development has decreased recently, pressure has increased for state and local governments to pay a larger share of the costs. In this situation a difficult question immediately arises-what is the capability of state and local governments to pay a larger share? Of course, there is no easy answer. Expenditures of public funds are policy outcomes of a government's political process in which political, economic, legal and other factors are involved in complex relationships. The traditional sources of capital funds for state and local governments include bond proceeds, tax revenues, and federal financial aid (state aid is also a major source of local government funds). The issuing of bonds is hampered by a variety of legal debt limitations, but there are means for circumventing the limitations. State and local governments vary widely in amounts of taxable resources available and in the extent to which these resources have been tapped. More effective use of revenue resources could be made in some cases. New sources of capital funds for water development ought to be considered-a fee on the use of water per se, for example. Costs associated with water use currently are imposed to cover development costs, but a state might impose additional use fees earmarked for a state water development fund. 相似文献
547.
Victor W. Lambou Stephen C. Hern William D. Taylor Llewellyn R. Williams 《Journal of the American Water Resources Association》1982,18(5):807-813
ABSTRACT: The relationship between chlorophyll u, total phosphorus, secchi disk depth, and trophic state were examined using data on U.S. lakes collected by U.S. EPA's National Eutrophication Survey. By comparing predicted secchi disk depths with observed summer secchi disk depths in 757 lakes, it was determined that in many lakes non-chlorophyll related light attenuation is important in controlling the amount of chlorophyll u produced per unit of total phosphorus. Ranking of 44 lakes by 18 different trophic state measurements and single and multivariable indices were compared with rankings provided by mean summer ambient total phosphorus and chlorophyll u. The trophic state measurements and indices were much more successful in ranking the lakes against total phosphorus than chlorophyll u, indicating that there are differences in the relative trophic rankings of many of the lakes depending upon whether primary nutrients or biological manifestations are used as the ranking mechanism. If the manifestations of nutrients rather than their absolute levels are the primary criteria for beneficial use of lakes, the use of many of the commonly employed trophic state measurements, which assume or imply that there is a constant relationship between total phosphorus or secchi disk and chlorophyll, can lead to erroneous conclusions and unnecessary costly management controls. Secchi disk measurements may be more useful as a predictor of ambient lake total phosphorus concentrations than of chlorophyll. 相似文献
548.
ABSTRACT: Variation among Carlson's three TSI values is unsettling to both the public and the scientific communities. Currently, there is no systematic way to account for differences in the three TSI values. Either (or both) of two mechanisms are proposed to account for differing TSI values on a regional basis. The first mechanism simply transforms the Secchi disk and phosphorus information to conform to their respective regional relationship with chlorophyll. The second mechanism uses the three TSI values to identify modifying processes in a lake and may indicate which TSI value (or combination of values) best reflects a lake's trophic condition. The format that is being proposed using information collected from 60 lakes in the Twin Cities (Minnesota) Metropolitan Area can be applied to other regional situations. 相似文献
549.
550.
重量法和冷凝法测量烟气含湿量计算公式的改进 总被引:1,自引:0,他引:1
本文对现有文献中用重量法和冷凝法测量烟气含湿量的计算公式进行了改进,使改进后的公式更准确、适用。 相似文献