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41.
J. C. Day 《Journal of the American Water Resources Association》1972,8(6):1120-1136
Neither Canada nor the United States attach much importance to the International Joint Commission (IJC) judging by the size of staffs and annual budgets. The Commission has been restricted to a relatively minor number of functions in the Great Lakes-St. Lawrence. It has investigated: the degree and causes of water and air quality deterioration; the effects of hydroelectric and navigation projects on water levels; the impacts of water-level fluctuations; and the feasibility of a deep waterway from the St. Lawrence to the Hudson River. Projects approved by the Commission have produced less than might be expected through no fault of the Commission. The Great Lakes Fishery Commission has promoted little international management. Budgetary limitations restrict its lamprey control program; institutional limitations restrict its ability to deal effectively with fishery problems. Commission responsibilities are limited to coordination and advisory functions. Since Canada and the United States have not chosen to refer most aspects of river basin management to international bodies, an institutional void exists in the Great Lakes Basin to consider these questions on a continuous basis. There is a need for expanded international cooperation. 相似文献
42.
王海忠 《中国人口.资源与环境》1996,6(1):55-58
本文认为环境生态是全球可持续发展的重要组成部分,必须在全球范围内,通过有效的国际合作和国际协调来加以解决。作者认为:国际合作应在国际性河流流域管理方面发挥重要作用。对全球温室效应问题,国际组织应重视科学研究,协调各国政府在能源税收、补贴和开发再生能源方面取得进展。此外,在保护地球生物多样性方面,国际组织可调试债务与自然环境互换机制。 相似文献
43.
关于生态补偿机制基本法律问题研究--以三江源国家级自然保护区生物多样性保护为例 总被引:4,自引:0,他引:4
本文以现代生态法文化观念为理论导引,在对传统生态法理论进行检视和对三江源区的生物多样性保护与生态裣机制进行尝试考评的基础上,以理论分析与实证调研相结合的方法,提出了具有建设性和可行性的法律对策。 相似文献
44.
45.
The research questions posed in this study highlight the importance of valuing proactivity in both prompting an individual to engage in proactive behavior and encouraging the expression of that behavior. We integrate a variety of constructs from the proactivity literature to gain a deeper understanding of proactive behavior as it relates to proactive motivation and supervisory performance evaluations. First, we draw upon self‐determination theory, expectancy–value theory, and the recent integration of the proactive motivation literature to hypothesize that proactive behavior is predicted by the interaction of “can do” and “reason to” proactive motivational states. Second, on the basis of performance theory, we hypothesize that the relationship between proactive behavior and performance depends upon the extent to which the supervisor values proactivity. Specifically, we argue that supervisors with proactive personalities are more likely to value and reward subordinate proactive behavior than passive supervisors. Results provide support for both of our hypotheses. Interestingly, results show that proactive behavior did not result in negative consequences but rather that there was a cost (i.e., lower performance rating) for not taking charge for employees with proactive supervisors. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
46.
根据国际上对于荒漠化概念的新说明以及由联合国环境规划署所资助的《中国荒漠化 (土地退化 )防治研究》课题报告中确定的荒漠化定义 ,荒漠化概念的内涵包括 :1)以土地退化为本质 ;2 )与人类活动相关联 ;3)以荒漠化景观为标志 ;4 )以脆弱生态环境为背景。因此我国的荒漠化类型除了风蚀作用形成的沙质荒漠化外 ,还有水蚀作用形成的土质荒漠化和石质荒漠化 ;荒漠化防治的重点区域除北方干旱、半干旱和半湿润地区以外 ,也包括南方湿润地区的红壤丘陵区和石质山区。其中属于水蚀荒漠化和土质荒漠化的红色荒漠化就是指我国南方红壤丘陵区在人类不合理经济活动和脆弱生态环境相互作用背景下 ,以流水侵蚀为主导作用而形成、以地表出现劣地为标志的严重土地退化。鉴于我国南方红色荒漠化现象在我国现实存在中的客观性、在全球变化中的特殊性以及在理论概念上的模糊性 ,有必要对其进行深入研究 相似文献
47.
Dietmar Zinner Michael H. Schwibbe Werner Kaumanns 《Behavioral ecology and sociobiology》1994,35(3):175-183
We investigated the factors affecting conception in a captive population ofPapio hamadryas. We collected data on reproductive states from 16 females over 12 years. Probability of conception was related to the outcome of the immediately preceding pregnancy and the fate of the preceding offspring. After abortions or when an infant survived more than 6 months, a female needed more cycles to conceive than when an infant died within the first 6 months post partum. The degree of estrus synchrony within, but not between, one-male units influenced the probability of conception. Females experiencing conceptive estrus showed less synchrony than those experiencing nonconceptive estrus. The number of females simultaneously in estrus within a one-male unit was negatively correlated with the probability of conception. Within our captive population, group size and male and female age had no influence on the probability of conception. The results indicate that sperm may be a limited resource in the one-male reproductive units of hamadryas baboons. Female-female competition for conception may exist and should influence the demography of one-male units. 相似文献
48.
Anders Berglund Gunilla Rosenqvist Sarah Robinson-Wolrath 《Behavioral ecology and sociobiology》2006,60(2):281-287
In a sex role reversed pipefish, Syngnathus typhle, we found that basic life history allocations were directly influenced by sexual selection. We investigated time allocation to foraging and mating, respectively, in a choice experiment, giving males and females, of small or large body size, a choice between food and a potential partner. We found that males were more interested in foraging than mating, i.e., were more frequently observed in front of the food than in front of the partner, whereas females were more interested in the potential partner. This reflects sexual selection operating differently on the two sexes, as males and females are relatively similar in other life history traits, such as growth, mortality, age of maturity, dispersal, and parental expenditure. Moreover, large individuals allocated more time to mating activities, small to feeding. Individuals more interested in mating compared to food were subsequently more critical when given a choice between a large (high-quality) and a small (low-quality) partner, whereas individuals more interested in food were not selective. These findings are consistent with our predictions: sex-role reversed males can be relatively sure of achieving one or more matings, and should allocate more time to feeding and, hence, to parental investment, growth and/or future reproduction. Females, on the other hand, have more uncertain mating prospects and should allocate time to imminent reproductive activities, thereby foregoing other life history traits such as growth and future egg production. By this, they also sacrifice future fecundity and attractiveness. 相似文献
49.
褚淑荣 《城市环境与城市生态》1996,(4)
本文简介国际环境管理标准ISO14000系列的内容,论述了其特点及其在国际贸易、产业结构、公司经营的影响,并提出了我国采用ISO14000系列应做的工作。 相似文献
50.
型煤燃烧固硫的钠离子效应 总被引:15,自引:0,他引:15
本文用脉冲二氧化硫荧光分析仪连续测试了煤样中二氧化硫的浓度,并用X荧光、X衍射和电子扫描电镜等方法,分析了添加钠离子样品的含硫率、物相及表面形貌。实验结果表明,钠离子添加剂改变了二氧化硫释放过程,抑制了硫酸钙的分解。灰样成分中既有稳定的三元化合物3CaO.3Al2O3.CaSO4,也有不稳定的化合物硫酸钙存在,说明钠离子添加剂对提高固硫率有促进作用。 相似文献