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51.
Miyun County,located in the northeast of Chinese capital Beijing,was underwent remarkable variations in land use in recent years.This paper aimed to detect changes in land use of Miyun from 1997 to 2005,and to qualify the response of ecosystem to LUCC based on ecosystem services valuation.With two-periods TM images,we got land use change data,and then ecosystem services values were calculated using ecosystem services valuation coefficients proposed by Chinese scholar Xie Gaodi.Results showed that water area,farm land and unused land decreased while residential land,forest land,grassland and orchard land increased during the study period.The loss of ESV was RMB 206 million and the main reason was the decrease of water area and farm land area.As for spatial variation,there were most dramatically land use change and ESV decline in reservoir ecological protection region.The coefficient sensitivity analysis indicates that valuation coefficients used in the study are suitable and results are reasonable.The driving forces of ESV loss were rapid population growth and economic development.More work should be done to make eco-environment stay healthy. 相似文献
52.
Supply of international environmental public goods must meet certain conditions to be socially efficient, and several reasons
explain why they are currently undersupplied. Diagnosis of the public goods failure associated with particular ecosystem services
is critical to the development of the appropriate international response. There are two categories of international environmental
public goods that are most likely to be undersupplied. One has an additive supply technology and the other has a weakest link
supply technology. The degree to which the collective response should be targeted depends on the importance of supply from
any one country. In principle, the solution for the undersupply lies in payments designed to compensate local providers for
the additional costs they incur in meeting global demand. Targeted support may take the form of direct investment in supply
(the Global Environment Facility model) or of payments for the benefits of supply (the Payments for Ecosystem Services model). 相似文献
53.
Qiu Ling Fang Chuanglin Shen Yuming Liu Xiaoli .Institution of Geographic Sciences Natural Resources Research Chinese Academy of Sciences Beijing China; 《中国人口.资源与环境(英文版)》2011,(4):82-89
The five central cities-Beijing,Tianjin,Shanghai,Guangzhou and Shenzhen-of the three most important strategic regions in China,namely Beijing-Tianjin-Hebei metropolitan region,the Yangtze River Delta and the Pearl River Delta,are taken as a comparative analysis on urban producer services’ competitiveness,especially focusing on the comparative advantages and disadvantages of producer services in Beijing.Firstly,based on an integrated indicator system including one objective hierarchy,four standard hierarchies and 35 indicator hierarchies,the study applies factor analysis model and analytic hierarchy process model reformed by entropy technology to measure the comprehensive competitiveness of producer services in the above five cities.Secondly,Beijing has comparative advantages of capital resource,industrial base,scientific research resource and market scale,since it takes the first place of the five cities in the comprehensive competitiveness of producer services,the competitiveness of industrial development,business environment and living environment,only inferior to Shanghai in the competitiveness of talent capital.Thirdly,Beijing has comparative disadvantages in the level of producer services development,urban innovation capability and living environment.Finally,five proposals are put forth to enhance the competitiveness of producer services in Beijing,namely perfecting the system of laws and statutes,supporting the development of industry association,implementing scientific development planning,introducing preferential fiscal and taxation policies and strengthening human capital reserve. 相似文献
54.
In this paper, we consider a two-period competition model of a remanufacturing supply chain consisting of three members: a new product manufacturer, a recycler and a remanufacturer. The manufacturer supplies new products in the first period and the remanufacturer participates in the competition in the second period. We consider three scenarios in the second period: (1) there is no government subsidy in the competition; (2) there is only government subsidy in the competition; (3) there are both government subsidy and tax in the competition. First, we give the optimal decision-making of the manufacturer, the remanufacturer and the government in the three scenarios; second, we analyse changes in the decision-making of the manufacturer and remanufacturer in the three scenarios and compare their results. We analyse the effects of government subsidy and tax and their asymmetric use on manufacturers’ and remanufacturers’ decision-making variables and competitive performance. We also take consumer awareness of environmental protection into account and examine its impact on subjects’ decisions. Lastly, we operate a numerical example to show the results. 相似文献
55.
From land cover change to land function dynamics: a major challenge to improve land characterization 总被引:36,自引:0,他引:36
Verburg PH van de Steeg J Veldkamp A Willemen L 《Journal of environmental management》2009,90(3):1327-1335
Land cover change has always had a central role in land change science. This central role is largely the result of the possibilities to map and characterize land cover based on observations and remote sensing. This paper argues that more attention should be given to land use and land functions and linkages between these. Consideration of land functions that provide a wide range of goods and services makes more integrated assessments of land change possible. The increasing attention to multifunctional land use is another incentive to develop methods to assess changes in land functions. A number of methods to quantify and map the spatial extent of land use and land functions are discussed and the implications for modeling are identified based on recent model approaches in land change science. The mixed use of land cover, land use and land function in maps and models leads to inconsistencies in land change assessments. Explicit attention to the non-linear relations between land cover, land use and land function is essential to consistently address land change. New methods to map and quantify land function dynamics will enhance our ability to understand and model land system change and adequately inform policies and planning. 相似文献
56.
Himayatullah Khan 《Environment, Development and Sustainability》2009,11(2):293-305
Using survey-based data approach for modeling the demand for environmental goods/resources, this study estimates income and
price elasticities of demand for improved environmental quality of two National Parks in Northern Pakistan. The study uses
data from two studies. The estimates indicate that improved environmental quality effects can be described as a luxury and
an ordinary and price elastic service. Confidence intervals show however that the classification as a luxury is not statistically
significant. Income elasticities of willingness to pay are estimated for a broad range of environmental services. The study
finds that income and willingness to pay vary directly and significantly. The elasticity estimates, in general, are greater
than zero, but less than unity. The study concludes that environmental improvements are more beneficial to low-income groups
than for high-income groups.
相似文献
Himayatullah KhanEmail: |
57.
This paper examines the impact of training programs on the ability of trainee watch officers to make decisions in collision avoidance situations.It draws on previous studies which have shown that experts are able to manage complex situations in an acceptable way. However, observations of students on simulators have revealed that many of them are unable to manage such situations or even to recall their main features. It is therefore necessary to identify new training tools that will give trainees the capacity to assess a situation quickly and accurately, and to perform satisfactory actions. These would be in addition to formal regulations.Exercises were designed to evaluate the impact of such tools on the decision-making process of trainees. The impact of the type of navigation experienced by trainees during their on-the-job training was also evaluated.Results showed that decision-making exercises did tend to improve the trainees’ capacity to analyse a complex situation; however, they did not have a clear impact on the manoeuvre performed. On the contrary, there was an obvious difference between the trainees who experienced complex avoidance situations during their on-the-job training period and those who did not.At a time where ship-owners are looking to reduce the length of the “on-the-job” training period, these results point to its vital importance. 相似文献
58.
59.
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
60.
危险评价第三维矢量的定性分析 总被引:1,自引:0,他引:1
危险评价主要针对危险导致事故发生的可能性与后果严重性进行分析,目的是为拧制危险提供决策依据,但现有的评价矢量并不能完全实现这一目的.可控性的提出完善了评价内容,并在控制对象、控制方案、控制时机等多方面为决策者提供参考,提高了危险评价结果的实用性. 相似文献