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161.
Mark E. Thompson Herbert H. Stoevener 《Journal of the American Water Resources Association》1983,19(6):889-896
ABSTRACT: An implicit price model relating residential lot value to price determining characteristics of land is developed to measure the benefits of a structural flood control project. Special attention is given to the selection of relevant price determining characteristics of residential lots. An implicit price equation is estimated for both the with and without project conditions. Flood damages are quantified through the use of a dummy variable indicating a flood plain location. The analysis shows that annual flood damages were reduced by $15,275. 相似文献
162.
Lloyd G. Antle 《Journal of the American Water Resources Association》1979,15(5):1408-1417
ABSTRACT: Recreation has produced substantial employment, incomes, economic development, and migration impacts since completion of the McCle-lan-Kerr Arkansas River Navigation System. These impacts support the influence of navigation, hydropower, flood control, and channel stabilization outputs on regional development. The marked success is not without substantial costs in public resources, including manpower which are devoted to recreational management. Increasing the share of financial resources obtained from recreational users and transfer of management responsibilities to nonfederal agencies, including private concessionaires is recommended. 相似文献
163.
河南金源公司祁雨沟金矿在新技术改造项目中引进了清洁生产工艺,可节约生产用水资金,提高劳动生产效率;减排生产废水和污染物等,实现经济和环境效益双赢。 相似文献
164.
通过分析煤矸石堆积所带来的环境问题以及在煤矸石砖与传统的黏土砖进行比较的基础上,从经济效益、环境效益以及社会效益几个方面分析了煤矸石砖在生态建筑中的应用前景,说明了煤矸石砖在生态建筑中应用的市场潜力是无穷的。 相似文献
165.
以湖南为例从分散蓄水与扩容蓄水、即时蓄水与重复蓄水、分级截流与设阻截流等角度,分析了稻田养鱼的生态防灾机制,得出湖南宜鱼稻田87.0万hm2,以蓄水30cm计算可蓄存107.9亿m3.通过重复蓄水、设阻蓄水,接纳多次降雨洪水,调节水分时空分布,创造减灾避灾的人工生态防灾系统,形成多物种共生共存的农田湿地生态系统,提高农田生态经济效益. 相似文献
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167.
在我国土地整理项目的规划设计中农业生态效益并未得到相应的重视,土地整理尚停留在对农业生产基础设施的综合改善阶段,我们试以设计的角度出发来探讨其产生的原因和改进的方法。 相似文献
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Recent theoretical and empirical studies have shown that male dominance is often at odds with female mate preference and that
indirect (genetic) benefits of mate choice may not be related to male dominance. We tested whether female preference corresponded
to male dominance and whether mating with dominant males conveyed benefits to offspring fitness in a small freshwater fish,
the African annual killifish Nothobranchius korthausae (Cyprinodontiformes), a species without parental care. The experimental design used controlled for the effect of male age,
possibility of sperm and egg depletion, and accounted for a potential that females express their preference through maternal
effects by manipulation of egg mass during ovulation. By sequentially mating females with males of known dominance, we found
that female N. korthausae showed no mate preference in terms of egg numbers deposited with respect to male dominance or body size and no congruent
mate preference to specific males was detected. However, males sired offspring with consistently higher hatching success and
the effect was repeatable across individual females. Thus, some males provided females with indirect benefits related to additive
genetic quality (“good genes”) and expressed via increased hatching rate, but this benefit was not related to male dominance
status or body size. 相似文献