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Land degradation is a global problem that seriously threatens human society. However, in China and elsewhere, ecological restoration still largely relies on a traditional approach that focuses only on ecological factors and ignores socioeconomic factors. To improve the effectiveness of ecological restoration and maximize its economic and ecological benefits, a more efficient approach is needed that provides support for policy development and land management and thereby promotes environmental conservation. We devised a framework for assessing the value of ecosystem services that remain after subtracting costs, such as the opportunity costs, costs of forest protection, and costs for the people who are affected by the program; that is, the net value of ecosystem services (NVES). To understand the difference between the value of a resource and the net value of the ecosystem service it provides, we used data on VES, timber sales, and afforestation costs from China's massive national afforestation programs to calculate the net value of forest ecosystem services in China. Accounting for the abovementioned costs revealed an NVES of ¥6.1 × 1012 for forests in 2014, which was 35.9% less than the value calculated without accounting for costs. As a result, the NVES associated with afforestation was 55.9% less than the NVES of natural forests. In some regions, NVES was negative because of the huge costs of human-made plantations, high evapotranspiration rates (thus, high water opportunity costs), and low forest survival rates. To maximize the ecological benefits of conservation, it is necessary to account for as many costs as possible so that management decisions can be based on NVES, thereby helping managers choose projects that maximize both economic and ecological benefits. 相似文献
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连续采样与五日法采样效果及费用的对比分析 总被引:2,自引:0,他引:2
通过对连续采样与五日法采样五种方法监测结果及所需费用的比较,得出连续采样方法监测结果更具有代表性,合理性,一次性投资大,但运行费用并不高的结论。 相似文献
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CHEN Wen-ying 《环境科学学报(英文版)》2003,15(4):541-547
Emission projection and marginal abatement cost curves (MACs) are the central components of any assessment of future carbonmarket, such as CDM (clean development mechanism) potentials, carbon quota price etc. However, they are products of very complex,dynamic systems driven by forces like population growth, economic development, resource endowments, technology progress and so on. The modeling approaches for emission projection and MACs evaluation were summarized, and some major models and their results were compared.Accordingly, reduction and cost requirements to achieve the Kyoto target were estimated. It is concluded that Annex I Parties‘ total reduction requirements range from 503--1304 MtC with USA participation and decrease significantly to 140--612 MtC after USA‘ s withdrawal. Total costs vary from 21--77 BUSD with USA and from 5--36 BUSD without USA if only domestic reduction actions are taken. The costs would sharply reduce while considering the three flexible mechanisms defined in the Kyoto Protocol with domestic actions‘ share in the all mitigation strategies drons to only 0--16%. 相似文献
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采用边际机会成本理论,对自然资源定价的原理和方法进行阐述,并比较了各种方法在实际应用中的适用条件,以及相互之间的优劣,为自然资源开发中的环境损失估算提供理论支持. 相似文献
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生态技术创新政府启动模式的机理与启示 总被引:2,自引:0,他引:2
生态技术创新是经济可持续发展的必要条件。由于环境资源的公共性,时滞性等特点,政府在生态技术创新过程中发挥重要的作用,是企业生态技术创新的主要推动力。政府启动模式的本 于政府借助法律或经济手段促使企业部分边际外部费用内部化。 相似文献
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Starting from a theoreticalnotion of capacity building this paperfocuses on the implications ofmulti-project baselines for costs andinstitutions. Availability of data and thelevel of data aggregation determine to alarge extent the cost of derivingmulti-project baselines. For localinstitutions this implies that theircapacity development needs are linked todecisions made on strictness of baselines.The initial higher costs of multi-projectcalculations in the development stage areeasily offset once more projects will usesuch a baseline. This paper argues theseinitial demands are not as high asexpected. Multi-project approaches willreduce transaction costs, especially forsmall-scale projects, will reducevalidation costs and likely reduce humanresource demands in other stages of theproject cycle. 相似文献
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吴彤坤 《石油化工环境保护》2002,25(2):17-19
本文从污水处理工艺的选择、设备比选,占地,能耗等诸多方面介绍了在设计中如何减少投资,降低污水处理成本的经验与体会,并提出了可行的方法与建议。 相似文献