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1.
长江流域湿地生态系统研究的意义和重点 总被引:7,自引:0,他引:7
长江流域是我国21世纪重点开放开发地区。长江流域生态环境是一个复杂的巨系统,并呈现恶化的趋势,而湿地生态系统是流域生态系统中极为重要的子系统,该子系统受到干扰和破坏,必将危及整个流域的生态平衡和生态安全。作者提出了研究长江流域生态系统的科学意义以及今后研究的重点。 相似文献
2.
森林生态服务价值评价研究有关问题的探讨 总被引:2,自引:4,他引:2
研究生态系统服务及其经济价值评价的理论与方法,已成为当前国内外可持续发展评估研究的焦点和重要内容。本文分析了森林生态系统服务功能价值评价研究的意义.论述了近年来国内外森林生态系统服务功能价值评价研究的进展,指出了其中存在的主要问题.并在此基础上探讨了森林生态系统服务功能价值评价研究的方向与重点,以期为今后的研究提供参考。 相似文献
3.
Bao Yonghong Wu Wenliang* Wang Mingxin Liu Wenna College of Resources Environmental Science China Agricultural University Beijing P. R. China 《生态经济(英文版)》2006,2(2):127-139
1. Introduction Ecosystem services are explicitly defined as “the natural environmental conditions and effects upon which people rely for existence that are formed and maintained by ecosystems and ecological processes” [1] . The valuation of ecosystem goods and services has become an important issue in the field of envi- ronmental protection and sustainable development, which also represents one aspect of the United Na- tions Millennium Assessment. At present, the re- search associated wit… 相似文献
4.
We critically review the literature that claims that existence values, or nonuse values in general, are a large and measurable component of total value for certain environmental resources. Our concern is not with the question “do nonuse values exist?” For some individuals they surely do. Rather, our concern is with two interrelated questions: are there operationally meaningful theorems which might lead to the specific measurement of nonuse values, and do we in fact have a body of credible evidence which shows that nonuse values, particularly components of any nonuse value, are “large”? We find nothing in the way of operationally meaningful hypotheses which would permit the estimation of values attributable to specific motives of individuals. We find no credible basis for claims related to either the measurement of existence and other motive-related values or claims for the “large” relative size of such values. In short, we question the conventional wisdom that such values are measurable and that they are significant as a component of total value. 相似文献
5.
中国生态资源破坏的经济损失:1985年与1993年 总被引:15,自引:0,他引:15
徐嵩龄 《生态经济(学术版)》1997,(4):1-11
本文较为明确地界定了有关生态资源破坏的经济损失计量的概念与方法,重估了1985年中国典型生态区及其它地区生态破坏的经济损失,估计了1993年中国全国生态破坏的经济损失。 相似文献
6.
于敏 《哈尔滨市经济管理干部学院学报》2015,(3)
夕随着经济的发展,时代的变迁,我国大学生社会主义核心价值观培育机制已显落后僵化。思政课肩负着培育大学生社会主义核心价值观的重任,作为思政课教师有必要对其培育机制进行探讨和研究。 相似文献
7.
自2002年农村税费改革以来,庆阳市作为甘肃省首批农村学校撤并对象,按照省统一部署,大力调整农村教育布局。经过了近十年学校布局调整,在减轻财政压力,提高中心办学的规模效应等方面确实取得了显著成果。但因中小学校布局调整受地理环境、经济条件、文化环境以及学校管理等多方面因素的影响。调整后的农村学校存在巨型学校,辍学率增加,寄宿制学校管理不当等问题急需解决。 相似文献
8.
目前国内兴起了建设湿地公园的热潮,为湿地资源的保护带来了强大的动力。然而湿地公园作为一种新兴的湿地保育措施,目前其设计建造大多还处于比较盲目的状态,没有固定规律可循。以湿地公园建设为依托,对湿地生态系统进行生态保护或恢复的设计理论探讨以及技术方法等层面的研究更是缺乏。考虑到湿地的重要生态价值,亟需从保护湿地生态系统的角度出发,提出一套系统的湿地公园设计和方法指导。湿地具有复杂的结构和功能,而不同湿地类型和环境条件下,湿地公园的类型和价值也不同,因而设计方案会有较大差异。因此,要做到根据不同湿地公园的类型,提出有针对性的设计方案和参数计算方法,从而对湿地公园中湿地生态系统的功能和价值进行有效的保护和恢复。 相似文献
9.
Tests of convergent validity and procedural invariance were used to investigate whether individuals lacking direct experience with a commodity can provide valid responses to contingent-valuation questions eliciting ex post use values. Convergent validity between samples with and without experience was shown to hold for dichotomous-choice responses, but not for open-ended responses. 相似文献
10.
历经50多年大开发,三江平原湿地面积急剧减少,生态环境日趋恶化,严重威胁到三江平原地区的生态安全和社会经济可持续发展。鉴于此,文章先对三江平原湿地开发历史进行了总结回顾,然后分析了农业开发对三江平原湿地生态环境的影响,最后对三江平原湿地可持续发展提出了四点建议。 相似文献
11.
Gil Avnimelech 《Technology Analysis & Strategic Management》2013,25(7):835-851
This paper analyses the development of biotechnology clusters in North Carolina (NC) and Israel. In both NC and Israel, when the biotechnology was identified as a potential strategic priority, the framework conditions were suitable for successful policy-targeting. NC presents a case of a successful transition from a traditional manufacturing economy to a knowledge economy. The most successful part of this transition was a policy-led development of a biotechnology cluster in the Research Triangle. While Israel also presents a case of a successful transition from a low-tech economy to a knowledge-intensive economy, Israel failed to develop a successful biotechnology cluster. We suggest that this failure is mostly due to a failure to implement policy to encourage such development. We argue that the elements, which separate NC's success from Israel's failure, are: a clear vision and strategic planning; timely response, long-term commitment; strong leadership; cooperation between the government, private sector and academia, and an adjustable policy-making process. 相似文献
12.
生态服务价值的发挥是现代都市农业的重要特征。本文以上海的都市农业为例,对农业生态系统的农产品提供功能、观光旅游功能、净化大气、涵养水分、保持土壤以及维持营养物质循环功能进行了评估。研究结果表明,21世纪以来,上海现代都市农业生态系统的服务价值不断上升,在提供了大量农产品的同时,还提供了巨大的生态服务功能,但同时间接经济价值随着耕地面积的减少而逐年降低,应引起我们的足够重视。 相似文献
13.
Path Dependence,Behavioral Rules,and the Role of Entrepreneurship in Economic Change: The Case of the Automobile Industry 总被引:4,自引:0,他引:4
This paper develops a complementary theory of path dependence based on rigidity resulting from the choice of management system within the firm. Rules-following behavior introduces rigidity which can lead to inefficient path dependence within a firm. Entrepreneurial alertness, in a crisis, can prevent lock-in from occurring since it leads people to alter perceptions and change behavior. An empirical look at the automobile industry explores the idea of rules-following behavior inducing path dependence development and the potential for change despite inefficient path dependent behavior. 相似文献
14.
Most contingent valuation studies in the literature utilized a pre-determined geographic market area for their sample frame. In other words, they did not include variables that would measure the extent of the geographic areas over which to aggregate willingness to pay. These studies implicitly assumed that the effects of geographic distance were moot; an assumption that could have led to an understatement of the aggregate benefit values computed in these studies. The overall goal of this study was to determine if distance affects willingness to pay for public goods with large non-use values. The data used came from a contingent valuation study regarding the San Joaquin Valley, CA. Respondents were asked about their willingness to pay (WTP) for three proposed programs designed to reduce various environmental problems in the Valley. A logit model was used to examine the effects of geographic distance on respondents' willingness to pay for each of the three programs. Results indicate that distance affected WTP for two of the three programs (wetlands habitat and wildlife, and the wildlife contamination control programs). We calculate the underestimate in benefits if the geographic extent of the public good market is arbitrarily limited to one political jurisdiction. 相似文献
15.
长江源区和黄河源区生态系统功能变化的对比研究 总被引:1,自引:1,他引:0
文章根据长江源区和黄河源区1986年和2000年的TM遥感影像解译数据,选取基于货币量的价值量评价法,应用Oostanza生态系统服务价值算法,分析了长江、黄河源区区域生态功能价值的动态变化.结果表明:1986~2000年长江源区、黄河源区的生态系统功能总体呈下降趋势,生态系统服务价值分别减少199亿元和30亿元,长江源区的生态系统功能缺失明显高于黄河源区;从功能分析.长江源区的气候调节功能、黄河源区的水源涵养功能变化最为显著;从结构分析,草地、湿地、水域是生态系统服务价值的主要构成,长江源区和黄河源区生态系统功能变化的主要驱动力存在根本差异. 相似文献
16.
We examine the impact of derivatives held by US bank holding companies on their market valuations over the period 2000 to 2010. By using bank-level data with detailed information on the notional amounts of derivative positions according to holding purposes and underlying asset types, our regression analyses provide three main findings. First, derivative instruments held for hedging rather than trading purposes contribute to enhancing market values. Second, the positive effects exhibit nonmonotonic patterns indicating that excessive amounts of derivatives holdings deteriorate market values. Third, interest rate derivatives are the main source of high valuations. 相似文献
17.
党的十八大提出全面推进依法治国、培育和践行社会主义核心价值观,不仅体现了中国共产党高度的法治自觉和价值自信,也体现出依法治国对培育、践行社会主义核心价值观的重要意义。因此,立足于依法治国,对依法治国助推社会主义核心价值观的培育和践行展开论证。 相似文献
18.
中国近代著名文学家、思想家和实业家郑观应(1842-1922)在其名著《盛世危言》中通过介绍西方慈善事业的发展情况,就赈贫济难社会福利提出中国应该学习移植西方慈善事业的诸多方面,并使之与中国实际社会生活情况相融合。并从对待赈贫济难的态度、“弱势群体”形成的社会原因及赈贫济难的必要性、赈贫济难的主客体、赈贫济难的管理方法和具体措施等诸多方面展开全面、具体的分析与论证。 相似文献
19.
初次分配中效率与公平不是孰轻孰重的关系,初次分配中的效率本身具有公平性质。针对初次分配中存在的不公现象,处理好效率与公平的关系具有紧迫性和现实性。要对影响初次分配中效率与公平关系的因素进行分析,区分产生收入差距的合理因素和不合理因素,通过完善社会主义市场经济体制、真正落实社会主义初级阶段的分配制度、制定并严格执行国家在微观经济领域制定的法律法规等措施,正确处理初次分配中效率与公平关系。 相似文献
20.
随着我国经济的迅速发展,中专毕业生作为国家建设队伍的重要组成部分,理应在市场经济中发挥其专业优势。但是,就目前我国中专生人才培养现状来看,许多学校并没有将这部分学生自身的特点与其专业、职业发展紧密联系在一起,导致很多中专毕业生不能适应市场经济发展的需要,专业优势无从体现。因此,这些学校应着力加强学生的思想道德教育,帮助其树立正确的人生观、价值观及科学的职业道德理念,使其能够发挥自身优势,做出应有的贡献。 相似文献