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261.
Benjamin M. Jones Christopher D. Arp Kenneth M. Hinkel Richard A. Beck Joel A. Schmutz Barry Winston 《Environmental management》2009,43(6):1071-1084
Lakes are dominant landforms in the National Petroleum Reserve Alaska (NPRA) as well as important social and ecological resources.
Of recent importance is the management of these freshwater ecosystems because lakes deeper than maximum ice thickness provide
an important and often sole source of liquid water for aquatic biota, villages, and industry during winter. To better understand
seasonal and annual hydrodynamics in the context of lake morphometry, we analyzed lakes in two adjacent areas where winter
water use is expected to increase in the near future because of industrial expansion. Landsat Thematic Mapper and Enhanced
Thematic Mapper Plus imagery acquired between 1985 and 2007 were analyzed and compared with climate data to understand interannual
variability. Measured changes in lake area extent varied by 0.6% and were significantly correlated to total precipitation
in the preceding 12 months (p < 0.05). Using this relation, the modeled lake area extent from 1985 to 2007 showed no long-term trends. In addition, high-resolution
aerial photography, bathymetric surveys, water-level monitoring, and lake-ice thickness measurements and growth models were
used to better understand seasonal hydrodynamics, surface area-to-volume relations, winter water availability, and more permanent
changes related to geomorphic change. Together, these results describe how lakes vary seasonally and annually in two critical
areas of the NPRA and provide simple models to help better predict variation in lake-water supply. Our findings suggest that
both overestimation and underestimation of actual available winter water volume may occur regularly, and this understanding
may help better inform management strategies as future resource use expands in the NPRA. 相似文献
262.
263.
基于独立环境报告的中日石油企业环境绩效信息披露比较研究 总被引:5,自引:1,他引:4
何丽梅 《中国人口.资源与环境》2009,19(6)
有效的环境绩效信息披露是正确进行企业环境绩效评估的基础.本文首次依据全球报告倡议组织(GRI)<可持续发展报告指南>(2006年版)中的30个环境绩效指标,对中石油独立环境报告中环境绩效信息披露的研究发现,中石油环境绩效指标披露不完整,重要的核心指标披露情况更不理想,年度间纵向比较还出现了倒退;定性指标披露多于定量指标;体现企业积极行动和效果的内容和数据披露得相对较为详细;存在选择性披露问题,可比性较差,相关信息披露也较为散乱,不利于读者进行环境绩效评估.对此,我国企业应重视环境原始信息的收集和处理,将环境相关信息纳入企业日常的信怠管理系统,在披露方法上则应综合借鉴相关国际组织的做法并不断加以改进;政府监管部门也应对环境信息披露做出系统指引和规范,并积极推动环境报告审计的发展. 相似文献
264.
Corruption is the main reason why resource-rich countries perform badly in economic terms. Corruption in resource-rich countries takes two main forms, rent-seeking and patronage. Resource rents induce rent-seeking as individuals compete for a share of the rents rather than use their time and skills more productively. And resource revenues induce patronage as governments pay off supporters to stay in power, resulting in reduced accountability and an inferior allocation of public funds. This paper systematically reviews the literature on natural resources and corruption, and outlines the main policy implications for donors and domestic policy makers. A main conclusion is that priority should be given to policies that address rent-seeking and patronage. In other words, policy in resource-rich countries should be less about macro-economic management and more about institutions to prevent rent-seeking and patronage, and about giving the right incentives to players in the resource sector. Moreover, all policies need to take into account their impact on rent-seeking and patronage, and some current policies may actually be harmful in this respect. 相似文献
265.
This paper develops a method for identifying and assessing long-term supply risks for mineral raw materials. The method is based on a combined evaluation of past and future supply and demand trends. By analysing raw material boom and bust cycles over the past 50 years, we have quantified indicators and defined benchmarks for identifying critical market situations. By applying the method, risks for supply shortage may be identified at an early stage. In addition, a numerical evaluation model has been developed for better comparison between various mineral raw materials. Compared to other assessment methods this method uses specific benchmarks for each raw material to better assess supply risks. The method is embedded within a systematic and comprehensive analytical approach. 相似文献
266.
The whole relationship between environmental variables and firm performance: Competitive advantage and firm resources as mediator variables 总被引:1,自引:0,他引:1
María D. Lpez-Gamero Jos F. Molina-Azorín Enrique Claver-Corts 《Journal of environmental management》2009,90(10):3110-3121
The examination of the possible direct link between environmental protection and firm performance in the literature has generally produced mixed results. The present paper contributes to the literature by using the resource-based view as a mediating process in this relationship. The study specifically tests whether or not the resource-based view of the firm mediates the positive relationships of proactive environmental management and improved environmental performance with competitive advantage, which also has consequences for financial performance. We also check the possible link between the adoption of a pioneering approach and good environmental management practices. Our findings support that early investment timing and intensity in environmental issues impact on the adoption of a proactive environmental management, which in turn helps to improve environmental performance. The findings also show that a firm's resources and competitive advantage act as mediator variables for a positive relationship between environmental protection and financial performance. This contribution is original because the present paper develops a comprehensive whole picture of this path process, which has previously only been partially discussed in the literature. In addition, this study clarifies a relevant point in the literature, namely that the effect of environmental protection on firm performance is not direct and can vary depending on the sector considered. Whereas competitive advantage in relation to costs influences financial performance in the IPPC law sector, the relevant influence in the hotel sector comes from competitive advantage through differentiation. 相似文献
267.
268.
自然资源利用权从产生的途径上看应属于特许物权,从内容和功能上看应属于准用益物权,两种物权属性并不相互排斥。自然资源利用权的双重物权属性符合环境保护的价值取向和价值选择。 相似文献
269.
国民信息素养的高低已成为一个国家在全球竞争中获得优势地位的关键,信息素养教育在全世界范围内备受重视。本文以信息素养为出发点,以当今高校对在校大学生信息素养培训的新要求为依据,通过信息的选择、检索、利用,个人创新和文化素养等五个方面的教育,论述了如何培养高校学生信息素养,使学生养成终身学习的习惯。 相似文献
270.
基于信息熵评价决策模型的突发公共事件应急处置指挥方案优选 总被引:6,自引:4,他引:2
提出基于信息熵评价决策模型对突发公共事件应急处置指挥决策中的作战方案进行优选的方法。首先介绍应急处置指挥决策的概念和过程;其次,分析了信息熵以及基于信息熵评价模型的多属性决策方法;最后,给出基于信息熵的评价决策模型在突发公共事件应急处置指挥方案优选中的应用。实地演练表明,该决策模型在应急指挥决策方案排序与优选是客观合理、切实可行的,能够为应急处置指挥决策提供一定的参考。 相似文献