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641.
Glen C. Filson 《Journal of Agricultural and Environmental Ethics》1993,6(2):165-184
This paper provides an analysis of a 1991 survey of the views of a stratified random sample of 1,105 Ontario farmers. Factor analysis, Kruskal—Wallis one-way ANOVA, chi-square and correlations were used to identify differences in farmers' attitudes toward rural environmental issues as a function of their demographic and farm characteristics. Younger, well-educated farmers, especially if female, were most concerned about the seriousness of rural environmental degradation. The largest operators expressed the greatest support for the use of agricultural chemicals, were most opposed to government conservation regulations and were least environmentally oriented. Such differences between Australian and Ontario farmers as the former's greater cautiousness about governmental regulation and receptivity to the Green Movement are a function of differing demographic and farm characteristics between Australia and Ontario. 相似文献
642.
本文根据沱江源头水源涵养林辽度砍代,导致源头蓄水量锐减,以及滥采乱控矿石,造成资源损失与灾害频繁的严峻现实,提出了建立沱江源头水源保护区的必要性。 相似文献
643.
贵州南部河谷热带性植物共计464种、2变种。主要构成3种植被类型:大型羽状复叶林、稀树草坡灌丛与肉质多刺灌丛。可分为11类经济用途:药用(139种)、纤维(38种)、野果(21种)、观赏(21种)、鞣料(18种)、饲料(13种)、油脂(13种)、淀粉(12种)、紫胶虫寄主(11种)、芳香(6种)、染料(5种)。资源流失与环境变化,使现存资源的保护与深层次利用成为当前的主要问题。 相似文献
644.
广西喀斯特岩溶石山面积占全区总面积的33.3%,森林植被的严重破坏是这些地区贫困落后的主要原因。对广西喀斯特地区的综合治理开发,要重视对森林植被及珍稀濒危植物的保护。该区至少有290种石山植物为珍稀濒危植物,它们中许多有重要经济用途,在保护的基础上,引种发展一些种类是山区脱贫致富的一条途径。 相似文献
645.
Creg S. Bishop Glen T. Broach Wendell H. Hester Vincent A. Sikora 《Journal of the American Water Resources Association》1982,18(2):189-195
ABSTRACT: The importance of water conservation was emphasized by a proposed National Water Policy which was established during the previous Carter Administration. This policy stressed water conservation on a national scale. Such a policy sought to apply one program to all water resources problems. Before implementation of this or another such policy, consideration must be given to those vast areas of the country which in reality do not have a shortage of water. One of these areas is the French-Broad River basin in Tennessee. This report was formulated in an effort to describe both the positive and negative effects of water policies which would bring about either a 10 percent or 30 percent reduction in water usage in this basically water rich area. The parameters used in the evaluation included selected economic, sociological, legal, and environmental impacts. 相似文献
646.
Raymond L. Anderson Thomas A. Miller Monty C. Washburn 《Journal of the American Water Resources Association》1980,16(4):642-645
ABSTRACT: During the drought year of 1977, unusually low river flows during the summer caused the City of Fort Collins, Colorado, to institute lawn watering restrictions for six weeks as a conservation measure. Water use during the restriction period decreased 41 percent below the previous year. The effectiveness of the restrictions, however, has been unclear because abnormally wet weather also appeared to reduce evapotranspiration rates during the period the restrictions were in effect. The statistical analysis indicates that the reduction in water use due to lawn watering restrictions was 603 acre-feet and that abnormal weather reduced use by an additional 659 acre-feet during the same period. During a period of normal evapotranspiration rates, such restrictions would be expected to reduce Fort Collins municipal water usage by 19.7 percent. 相似文献
647.
William Whipple 《Journal of the American Water Resources Association》1981,17(5):814-819
Water conservation is a much emphasized policy of the Federal government. Discussion of water conservation proposals often involves confusion between a conservation “ethic,” which is an end in itself, and conservation as a means for attaining various economic objectives. Analysis indicates that outside of ground water “mining.” water is usually a renewable and reusable resource. During periods of normal precipitation, water conservation should be employed only when the value of the water saved exceeds the cost of effecting the savings. Water conservation is most valuable as a drought contingency tactic. Water conservation as a substitute for structural provision to meet normal water demand growth is apt to prove shortsighted. 相似文献
648.
Ronald C. Griffin John R. Stoll 《Journal of the American Water Resources Association》1983,19(3):447-457
The concept of water conservation has increased in importance because of revisions in the rules and procedures for performing cost-benefit analyses of federal water projects. These revisions include a requirement that nonstructural and water conservation measures be incorporated into economic assessments of projects. Project analyses will now proceed as if water supplies were allocated “most effectively,” that is, to their highest valued uses. A related requirement provides that the net benefits of any project should now be valued using willingness to pay measures. A specific cost-benefit methodology accommodating the revisions is constructed and discussed. Informational requirements for applying this methodology are identified. In addition to being consistent with federal mandates, this technique offers important advantages over the traditional “requirements” approach to water supply planning. 相似文献
649.
Theodore M. Schad 《Journal of the American Water Resources Association》1978,14(2):302-312
ABSTRACT: In 1973 the National Water Commission concluded its five-year study of national water policy by issuing a massive report containing over 200 recommendations for improvements in the way the Nation deals with its water resources. The Carter Administration is now engaged in another water policy review which incorporates many of the policies espoused by the National Water Commission. In this paper, presented at the 13th American Water Resources Conference in Tucson in November of 1977, the author describes the work of the National Water Commission and the actions taken on its recommendations. 相似文献
650.