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1.
各位代表、各位来宾: 大家好! 首先,我代表中国可持续发展研究会对参加2007年学术年会的嘉宾、专家与学者表示热烈的欢迎,向多年来支持和致力于研究会工作的各界领导、各位同仁表示衷心的感谢!  相似文献   

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The main objective of this study is to simulate the potential vegetation types on the basis of environmental parameters.The paper took Barkam County in a mountainous region of the Eastern Tibetan Plateau as the study area.The vegetation distribution was mapped in 1994 and 2007 based on TM remote sensing images by object-oriented interpretation method.We overlaid the two maps to find out the vegetation patches which have not changed,and took them as stable types.Fifty per cent of the stable patches were randomly sampled to operate the logistic regression with related environmental parameters;others were used as test data of simulated results.Seven environmental parameters were mapped,including elevation,slope,aspect,surface curvature,solar radiation,temperature and precipitation,based on DEM data and meteorological site data by GIS technology.The relationship between the spatial distribution of vegetation and environmental variables were quantified by logistic regression.The distribution probabilities of each vegetation type were calculated.Finally,the spatial distribution of potential vegetation was simulated.This research can provide a scientific basis for vegetation restoration and ecological construction in this area.  相似文献   

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沿海城市在全球发展中具有重要的战略地位,然而特殊的地理位置和高度集中的人口及财富也决定了其面临灾害具有较高的脆弱性,即同等灾害强度下,沿海城市遭遇自然灾害时的人口伤亡更多、经济损失更大。从灾害系统承灾体的角度,分析影响灾害脆弱性的基础设施、城市形态与结构和灾害管理体制等5个方面,顺应脆弱性评价定量化的趋势,依据一定的原则,不分灾种,面对区域和人群,选取代表性指标尝试构建了沿海城市自然灾害脆弱性的评价指标体系,利用AHP法对该区域相应指标的权重进行确定,建立了脆弱性模型,并在收集和标准化数据的基础上,以上海市浦东开发区为例进行了实证分析。结果证明,模拟结果与实际情况基本吻合,可以为沿海城市防灾减灾提供科科学依据,有一定的参考价值。  相似文献   

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渤海海洋资源价值量核算的研究   总被引:3,自引:0,他引:3  
探讨海洋资源核算的目的在于重新建立海洋资源价值观,科学评价、合理开发利用海洋资源,为实施有效的管理、保障区域海洋经济的可持续发展提供依据。以海洋资源分类为基础,构建了水产,港址、海洋石油、海盐、滨海景观、滩涂等海洋资源价值量评估的基本方法。以渤海为研究区域.以2004年为基准年.对上述海洋资源初步进行货币化的价值量核算。结果表明:环渤海地区主要海洋资源价值为8028亿元.相当于当年环渤海地区生产总值的24%;海洋资源价值以港址资源为主。占总价值的38.56%;海洋资源价值主要分布在山东地区。占总价值的47.4%;单位岸线海洋资源价值差异大,其中天津最高为7.84亿元/km;海洋资源开发雷同现象严重.环渤海各地区均以海洋渔业、港口运输业和滨海旅游业为主。  相似文献   

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湖南省汨罗市再生资源产业集群升级研究   总被引:3,自引:1,他引:2  
随着我国经济快速增长。生态建设和环境保护的形势日益严峻,再生资源产业作为根本解决资源枯竭、能源短缺、环境污染等问题的有效途径,对我国资源节约型、环境友好型社会建设具有重要战略意义。汨罗市再生资源产业历史悠久,已经初步建立起再生资源回收系统、再生资源加工利用系统和废弃物资无害化处置系统.呈现出产业集群发展雏形。针对目前汨罗市再生资源产业集群存在的产业链条短、产品加工度不高、附加值低等问题。必须通过再生资源产业价值链技术创新、链核延伸和链条辐射。实现汨罗市再生资源产业集群的动态升级。加速汨罗市再生资源产业集群区域品牌的形成。为其他地区和城市再生资源产业发展提供重要经验借鉴和发展启示。  相似文献   

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Margalla Hills National Park(MHNP) is a declared natural reserve of Pakistan,and Saidpur village is located at its foothills.To sustain livelihood,Saidpur community relies on natural resources and has established an intriguing relationship with the surrounding ecosystem.Human intrusion and related impacts were investigated through self-structured questionnaire from village community to gather information about demography,life practices,natural resource use,and their perception about the environment.Quadrat analysis revealed that the overall plant density was<4 plants/m~2,whereas ordination biplot has indicated significant reduction in plant cover and sparse distribution of species in areas close to human settlement.Survey results show that more than 50%families rely on forest wood as fuel source.Logistic regression has identified education paucity(odds ratio,OR=2.6,95%confidence interval,CI=1.0-6.7),large family size(OR= 5.0,95%CI=1.5-16.6),and fuel type(OR=3.5,95%CI=1.2-9.9)as significant predictors of accelerated forest cutting in MHNP.Male members were mostly illiterate and in favor to promote construction activities which reflects their low concern and casual attitude toward resource conservation.In this study,lack of awareness and peoples’ dependency on natural resources emerged as priority challenges,and hence,we suggest provision of alternate fuel sources,better education and sustained income resources as incentives to bring behavioral change.It is pivotal to involve local community before the adoption of any conservation plan as intervention strategy to protect MHNP ecosystem.  相似文献   

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用水户参与灌溉管理模式运行机制与绩效实证分析   总被引:5,自引:1,他引:4  
我国是一个水资源非常短缺的国家。推行用水户参与灌溉管理(SIDD)模式是解决这一难题的重要措施之一。SIDD管理模式运行机制可以从产权制度安排、运营制度安排、激励制度安排、组织制度安排等进行分析,其运行绩效体现在用水机制、管理方式、交易成本降低等方面。结合江苏皂河灌区管理体制改革,分析了SIDD管理模式的运行机制、绩效及存在的问题。为完善这一管理模式.主要的建议是:制订相关的规章制度,使农户广泛参与;建立多元化的投入机制.拓宽资金来源渠道;遵循市场经济运作机制,深化农业水价改革;明确政府职能。加强指导、服务和监管。  相似文献   

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乡村道路建设对于农村的经济发展、降低贫困等具有重要意义,对于如何评价乡村道路收益一直以来都存在着争议。传统的成本-效益分析方法具体来说有消费者剩余方法、生产者剩余方法等,但是由于这些方法都存在共同的缺陷,即不适合衡量交通流量小的地区乡村道路收益,对乡村道路收益的衡量依然存在低估的问题,引起了诸多学者的批评。本文通过构建新的计量经济学方法,利用对湖北农村家庭的实际调查数据,发现乡村道路建设可以有效地节约农村家庭交通成本、提高男性和女性劳动力的农业工资水平、提高学龄儿童的入学率、降低农业和非农业生产投入产品的价格等,对农村家庭具有重要的即时和长期的正向利益影响。  相似文献   

10.
This paper firstly extends the single period forest optimal harvesting decision model to infinite periods,in order to indicate how to determine the optimal rotation period aimed at maximizing forest revenue in all directions when repeat planting and harvesting trees on the same plot of earth till infinite future.The study also analyzes the influence of discounted rates,timber price,harvesting costs,planting costs,and tax on the determination of optimal rotation period;and how the optimal rotation period will change when we introduce the factors of continuously rising timber price and ecological revenue.Secondly,the authors introduce the intergenerational equity principle into the above model to design a resource-exploiting mode which satisfies bom the dynamic efficiency principle and the intergenerational equity principle.Last but not least,the research applies the above model to the analysis of Chinese forestry economic policy and explains the economic theory of institutions such as Government Purchasing Ecological Forest,Tree Compensation,and Forestry Subsidization,which provides a necessary theoretical foundation for future application of these new institutions.Besides,in regard to mis theoretical framework,the authors analyze the necessity of the Natural Forest Protection and Grain for Green projects which are currently being implemented in China.We also point out the emphasis of work to insure the project sustainable and successful.Finally,the research discusses the enterprise’s incentive to over-the-quota harvesting and the government’s means of restricting such behavior,which highlights the fact mat improved supervision and higher penalties are helpful in restricting over-the-quota harvesting.  相似文献   

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