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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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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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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   

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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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Climate warming has prolonged the optimization of crop-growing seasons,shortened actual growth periods,and changed crop-planting boundaries.It also has boosted crop yields in certain regions while compromising crop quality and affected the occurrence of meteorological disasters and pest diseases damage,which has resulted in reduction in grain yield.Crop production systems will evidence more sensitivity to climate change in future;for example,with an increase of 1°C in temperature,the average growth period will be shortened by 17 days for winter wheat and 7-8 days for maize and rice.Of course regional differences will exist.Climate change will threaten crop yield stability and affect crop quality.Vulnerability will be addressed in regard to extreme climatic events,which include reducing exposure and improving adaptive capacity,because the exposure of rain-fed agriculture is greater than that of irrigated agriculture.Therefore,we propose three suggestions to reduce the vulnerability of crop production systems to climate change.First,strengthen the evaluation capacity construction of sensitivity,which includes(1)refining and improving all types of evaluation indicator systems and models;(2)innovating and developing evaluation methods and tools;and(3)combining field observation and case studies,so that(1)the impact of climate change and sensitivity can be assessed scientifically;(2)uncertainty in the study can be identified and reduced;and(3)improved understanding of climate systems and their changes,climate change impact,and sensitivity will be achieved.Second,strengthen adaptive capacity construction for crop production systems,which includes(1)rebuilding existing farmland infrastructure to improve meteorological disaster defences;(2)adjusting agriculture structure and adopting new crop varieties with enhanced resistance;(3)popularizing water-saving technology and dry farming technology;and(4)further researching interdisciplinary theories and methods.Third,strengthen function construction for natural and social s  相似文献   

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With the rapid social and economic development of the Tibet Autonomous Region,the situation in regard to energy supply and demand is increasingly tense.Meanwhile,the development of renewable energy in Tibet has been given considerable practical significance by its peculiar ecological environment.Given the complementarity of renewable energies in Tibet,using the method of factor analysis,we derived four major factors:level of economic development,social development,industrial development,and energy endowment,which help to evaluate development conditions in different regions of Tibet.Treating these four factors equally,we used the hierarchical clustering method to determine the order of regional development.Thus we acquire a three-stage planning project for renewable energy.In the first stage,Lhasa plays a leading role in promoting the development of renewable energy,particularly that based on solar and wind energy.There are two phases in the second stage,the first being to simultaneously develop solar and wind energy in Xigaze and Nyingchi.The second is to develop solar and wind energy in accordance with the time of year in Qamdo,Nagqu,and Ali,with 1.145billion kWh electricity to be generated.The third stage is to develop energy production in Lhoka Prefecture,with 1.369billion kWh electricity to be generated.At the end of the three-stage project,consumption of available electricity will have reached 4.045 billion kwh,with major social and economic benefits.  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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经济增长下的渤海环境容量预测   总被引:1,自引:0,他引:1  
据1999,2002—2005年渤海活性磷酸盐、石油类、无机氮的水质监测资料。采用箱式模型。估算渤海及各分区现状下及不同经济增长率下的环境容量预测值。估算结果显示.分污染物来看,各年份均是无机氮较大,石油类次之.活性磷酸盐较小;分区域来看。各年份各污染物均是渤海中部较大,辽东湾、渤海湾次之,莱州湾最小;从时间变化来看。除活性磷酸盐外。石油类和无机氯自2002年到2004年逐年减小。假设渤海污染物排入量随着经济增长每年增加5%。以达到环境容量极限值需要的年数来看。自2005年。分别在7年、4年、17年后渤海的石油类、活性磷酸盐、无机氮将达不到一类水质标准,50年、19年、37年后超过四类水质下环境容量极限值;假设随着经济增长污染物排海量每年增长10%,那么自2005年起。29年、13年和22年后三种污染物将超过四类水质下环境容量极限值。  相似文献   

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A comparative analysis of field observations and experiments on the distance and rate of dispersal of self-sown Scotch pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) progeny has shown that the rate of their hydrochorous dissemination downstream is an order of magnitude higher than the rate of dispersal in upland areas. A hypothesis assigning priority to the role of hydrochory in the expansion of conifer populations to the tundra (periglacial) zone along with climate warming has been formulated and substantiated by comparative isozyme analysis of populations in transects lying along and across rivers.  相似文献   

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退耕还林工程费用有效性的影响因素分析   总被引:3,自引:0,他引:3  
费用有效性评价是工程评价的重要方面。从政策制定和执行角度对退耕还林的费用有效性及其影响因素进行分析。具有重要的意义。利用实地调研数据和相关统计数据.从退耕地选择和造林入手对退耕还林工程实施的费用有效性殛其影响因素进行考察.并尝试对这些因素的作用机制进行了分析。研究指出由于缺乏长期的和有效的退耕还林规划以及相关政策措施的缺失.使得退耕还林费用有效性的损失在微观层面和宏观层面广泛存在。而各利益主体的利益不相害性是影响工程有效实施的基本矛盾。有必要在遇耕还林中确立明确的规划、清晰的退耕地选择标准。建立和完善管理信息系统和及时有效的反馈和控制机制。构建协调多方利益的长期稳定的生态补偿机制。从而改进退耕还林工程的费用有效性。  相似文献   

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以加入WTO为标志.中国积极参与经济全球化已成为一种必然.但由于我国的国土规模、自然环境、气候条件等方面的地区差异很大,地区之间在发展水平上一直存在着差距,地区发展不平衡是个长期的国内政治经济现象.这种地区发展的差距表现为各类地区融入经济全球化的程度不同,反应不同.有些地区能够借助经济的全球化而发展自身,有些地区则无法从中受益,甚至因而处于更加落后的境地.本文从三大经济地带、各经济区和各省(市)区三个屡次分析和探讨了不同区域对经济全球化响应的差异,并对全球化条件下我国内部区域一体化格局进行了深入的研究.  相似文献   

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实施生态补偿制度是保障黄河三角洲高效生态区可持续发展的基础。该文在明晰黄河三角洲高效生态区生态补偿原则和利益相关方各自的责任和义务的基础上,提出并设计了黄河三角洲高效生态区生态补偿平台建设思路和生态补偿运行机制。生态补偿平台建设主要包括:建立由政府主导的生态补偿交易市场平台;建立以生态补偿保险、生态补偿期货、互助基金、证券化交易为主要内容的生态补偿风险保障平台;建立以相关独立认证和监测(检测)、资产评估、审计、代理等机构组成的生态补偿交易中介服务平台;建立生态补偿监管平台。生态补偿运行机制需要将法制建设、财政扶持、税收调节和保障措施等系统化:推进《生态补偿法》、《黄河三角洲高效生态区补偿协定》的制定;完善并建立中央财政转移支付、财政转移制度纵向化、"环境财政"等制度;改革创新区域或专项税收制度;构建完备的生态补偿评估、考核、监督管理体系,等等。  相似文献   

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In the crustacean Eudiaptomus gracilisSars, relationships between mortality (D) and the ratio of main cations (R, the ratio of the sum of potassium and sodium equivalent concentrations to the sum of calcium and magnesium equivalent concentrations) were studied. The calculated regression equation D= 315 – 355/Rwas used for predicting the state of E. gracilispopulation in Lake Poppalijarvi (Karelia) polluted with mining waste. At R< 0.47, the population will survive; at R> 1.53, its extinction should be expected. The results of hydrobiological observations on Lake Poppalijarvi confirmed the prognosis based on the equation.  相似文献   

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中国发展低碳建筑的困境与对策   总被引:3,自引:1,他引:2  
本文采用文献资料法、和数据分析法,以及系统科学的思想,分析了我国20年来城市建设突飞猛进发展过程中,留下的高碳排遗憾,对房地产业、建筑业发展过程中的能源利用到碳排放问题进行了深入的剖析。作者认为:我国发展低碳建筑,目前面临着认识问题,激励机制问题和投入不足等方面的问题;提出了建立建筑物碳排量评价标准,规范房地产开发行为;制定低碳建筑标准,促进建筑业结构调整;以节能减排为导向,理顺能源价格;以及弘扬祖国传统文化等建议。得出了发展低碳建筑应该通过文化理念的回归与进步,依靠技术跨越式发展和制度约束才能实现的结论。然而技术的跨越式发展需要大量的投入,制度的约束难免会影响原有的发展方式。可见低碳建筑的发展的确是任重道远。  相似文献   

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地质旅游研究进展   总被引:1,自引:0,他引:1  
自20世纪70年代以来,地质旅游受到世界各国的重视,并在国内外相关领域的研究中积累了丰富的经验和文献。本文从地质旅游的含义、地质旅游活动发展历程和国内外理论与实践建设出发对地质旅游进行归纳和总结。综述表明,地质旅游越来越受到游客、地方和政府的关注和重视,是一重要的生态和可持续旅游型式。  相似文献   

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Northern Rangelands of Kenya have continued to grapple with management challenges largely due to a lack of understanding of the dynamics thereof. Eroding customary institutions and new institutional arrangements characterize the system suggesting that adaptation is taking place to cope with the change. It is imperative that these socio-ecosystems adjust to the disturbance without disintegrating into a different state that is controlled by a different set of processes to ensure sustainable rangeland management. To understand the nature of change, the study sought to evaluate institutional arrangements engaged in tackling growing socio-economic and ecological factors challenging development within the last decade. Three study sites namely Kinna, Makurian and Westgate, representing three types of institutional arrangements (elders only, group ranch committee and community conservancy board), were investigated. Key informants, focused group discussions and household survey methods were used to gather data. Data were managed and analysed using Ms Access, Ms Excel, social network analysis and SPSS. Findings indicate that more actors (internal and external) are engaging in management of social economic and ecological factors challenging development within the last decade. The co-management approach allows increased capacity to tackle these challenges and further presents more opportunities for a diversified livelihood, two key features of ecosystem resilience. Findings are useful as the Kenya government implements the National Land Policy that recognizes the need to restructure community land and its management.  相似文献   

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The main regulatory mechanism of populations is revealed for some insect groups (Carabidae, Curculionidae, Chrysomelidae, and Hemiptera) on islands of the Kuibyshev Reservoir. This mechanism is the dynamics of the ratio of species with imaginal and preimaginal winter diapause. The extent of these dynamics depends on the stability of habitats, which in turn depends on water-level conditions in the reservoir. The period of adaptation of the community of carabids of the most flooded biotope to the extreme impact of water conditions is determined.  相似文献   

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