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1.
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   

2.
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   

3.
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   

4.
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   

5.
中国进出口贸易中的隐含能估算   总被引:11,自引:0,他引:11  
采用投入产出法。估算了1997-2006年中国进出口贸易中的隐含能。在考虑隐含能和进出口能源产品的情况下,都按我国的能耗效率对进出口进行的保守估计发现:1997-2006年,我国的能源进出口基本持平.其中1999-2005年是一个微弱的能源净进口国,而1997。1998和2006年却是能源净出口国;按照日本的能耗效率对进口产品进行调整后的乐观估计发现中国则是一个更大的能源净出口国,每年能源净出口量在10000-50000万t标煤之间,其中1997-2002年我国能源净出口量占当年能源消费总量的10%左右。之后该数字迅速增长,2006年更高达18.8%。可见我国进口的能源(包括进口产品中的隐含能)又以出口产品的形式输出到了国外。从能源净消费的角度看我国并没有多消费世界上其他国家的能源。虽然我国近年来能源产品进口增加较快,但我国快速增长的净出口使这些能源又“隐含”在产品中离开了中国。  相似文献   

6.
环境问题的外部性属性决定了其不可能依靠市场解决。必须进行适当的政府干预。研究外部性的意义在于内部化,即纠正市场失灵。本文对外部性进行了主体划分.建立了以时间和空间为基准的外部性分类矩阵,构建了外部性绝对大小和相对大小的概念模型。基于这些研究.分别回答环境问题是否需要管理、由谁来管、采取什么手段以及管到什么程度的问题.并由此提出“三级两层”的中国环境管理体制框架。跨行政区的环境外部性应当由上一级政府负责管理,在总社会成本最小化的前提下.应当在尽量小的范围实现较高程度的内部化,内部化手段的搭配符合费用效果最好原则。建议中国的环境管理体制改革在保留国家、省、市三级环境管理机构的基础上。设置环保总局和省环保局的分局以便直接管理省际、市际等外部性。  相似文献   

7.
This article will briefly discuss the implications of recognition of ecological justice in relation to environmental education(EE) and education for sustainable development(ESD).It is argued that the present conception of environment taught through EE and ESD negates the subjectivity of non-human species and ignores the ethical imperatives of ecological justice.Evocating environmental ethics,major directions integrating ecological justice into EE and ESD are proposed.  相似文献   

8.
<正>Chinese Journal of Population Resources and Environment,Print ISSN 1004-2857,Online ISSN 2325-4262,Volume 11,2013,Chinese Journal of Population Resources and Environment(www.tandfonline.com/tpre)is a peer-reviewed journal published in March,June,September,and December by TaylorFrancis,4 Park Square,Milton Park,Abingdon,Oxon,OX14 4RN,UK.  相似文献   

9.
<正>Chinese Journal of Population Resources and Environment,Print ISSN 1004-2857,Online ISSN 2325-4262,Volume 11,2013.Chinese Journal of Population Resources and Environment(www.tandfonline.com/tpre)is a peer-reviewed journal published in March,June,September,and December by TaylorFrancis,4 Park Square,Milton Park,Abingdon,Oxon,OX14 4RN,UK.  相似文献   

10.
Food traceability systems are capable of overcoming or alleviating problems caused by incomplete and asymmetric information on food markets.This study conducts an empirical analysis using 308 supermarket samples from China’s Beijing,Guangzhou,and Qingdao to determine the factors that influence supermarket behavior when operating traceability systems.The results show that operating profits(generated from food traceability systems),scale of operation,level of economic development(of a city),and government subsidies will positively affect the decision of supermarkets to use traceability systems.At the same time,government policies promoting food traceability systems should have a long-term role.  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
18.
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   

19.
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   

20.
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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