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161.
基于资源合理性、经济可行性、生态安全性三个角度选取17项指标构建指标体系,通过熵值法计算各指标的权重,求取非资源合理性( NREI)、经济可行性( EEI)、非生态安全性( NESI)3项综合指数,运用改进的三角模型对佛山市2004年-2011年土地可持续利用状态和趋势展开分析和评价。研究表明:佛山市土地可持续状态总体较差,并且呈现不断恶化趋势。  相似文献   
162.
生态文明建设是政府、市场、非政府组织和公民等多元主体合作治理的整体性系统性实践活动,多元主体合作治理的实现依赖于制度环境、组织因素、共同目标和信息沟通等多个关键条件,同时,合作治理需要各主体按照生态文明建设的要求明确和重塑角色定位,进而通过健全多元主体参与生态文明建设法律保障体系,健全生态补偿和生态支出竞争使用机制,建立信息交互制度,寻求多元合作模式,最终实现统筹协调、联动增效的生态文明建设合作治理.  相似文献   
163.
随着我国工业化的不断发展,在我国的主要经济发展地区的雾霾天气不断爆发,使我国的大气环境日益恶化,严重影响了人们的日常生活和身体健康。PM2.5作为雾霾的重要组成成分,也日渐成为环境领域的研究热点问题。随着全球性变化研究领域逐渐加强了对土地利用与生态环境的相关研究,因此无论从法律和社会经济发展的角度,还是从生态资源保护与环境可持续发展的角度,土地利用与PM2.5的相关研究都显得相当重要。研究目的:分析武汉市各类用地类型与PM2.5浓度的相关性程度。研究方法:使用ENVI与ArcGIS对武汉市2013年MODIS气溶胶产品进行空间分析与插值处理,再应用SPSS将其与武汉市2013年10个观测点的PM2.5浓度数据作相关性分析,以证实MODIS气溶胶厚度与PM2.5浓度的相关性,并建立两者的线性回归方程,然后利用计算后的武汉市整体PM2.5浓度分布与各土地利用类型进行相关性研究。研究结果:武汉市PM2.5浓度有明显的空间分布特征,绿化面积比例与PM2.5浓度呈显著负相关,建设用地面积比例与PM2.5浓度呈显著正相关,未利用地面积比例虽然与PM2.5浓度呈正相关,但相关性较低,而耕地与水体对PM2.5浓度没有显著影响。研究结论:土地利用类型对武汉市PM2.5浓度的分布有显著的影响,其与搭载MODIS传感器的遥感卫星监测方式的结合能成为研究大范围特定区域PM2.5浓度空间格局的新方法,并且增加城市绿化面积,控制建设用地规模能有效减少PM2.5浓度。  相似文献   
164.
While fossil fuels greatly contribute to human society,they pose great challenges to natural resources,the environment,and climate change.Developed countries,like the United States,formulated strategic measures to ensure their sustainable development and leading positions in the world.These measures include new green policies,development of shale gas,revitalization of nuclear power,energy independence,reindustrialization,and new low-carbon development based on a combination of Internet technology and renewable energy.Developing countries are also trying to introduce balanced strategies of poverty alleviation and sustainable development.Globally,industrial civilization is being transformed to ecological civilization and green,low-carbon development is a global trend.Addressing climate change provides new strategic factors to further this development.China should take substantial actions to realize sustainable development in a new road:China is in the critical stage of changing its development mode,so it is vital to choose an appropriate development path.This extensive development comes at the high price of consuming too much resources and scarring the environment.Mitigation and adaptation strategies for addressing climate change can help the transition of development.Based on the analysis of the development data of developed countries,the author introduces the concept of"two-type developed countries"with an understanding that not all developed countries must take the same development mode.He also holds the view that China should achieve modernization in a more energy-saving and more carbon-efficient manner compared with that of two-type developed countries.An analysis of"two competitions"that China is facing shows that changing the developing mode is urgent and China should grasp this opportunity in the next five to ten years,which is a key period for this transition.This paper discusses the low-carbon development goals and the three-step process.Low-carbon development does not necessarily restrict economic development.It,however,can expedite the transition of the development mode and this is a low-carbon and green development path.Transition of the development mode includes implementation of China’s green and low-carbon energy strategies,low-carbon society construction,development of agriculture and forestry,garbage sorting and utilization,innovation of urbanization,etc.Improvement of national infrastructure construction includes water safety,environment and climate monitoring system,intelligent energy web,basic database,etc.Addressing climate change can significantly improve the nation’s basic research level.In summary,it mitigates backward production capability,extensive development,and environmental damage while promoting technological advancement,scientific development,and ecological civilization.  相似文献   
165.
水库底层低温低氧水从坝体下泄或渗漏,可能对下游生态产生不利影响。通过对湖北温峡水库下游温峡河225 km河段的野外试验,测量溶解氧、水温等指标的日变化和沿程变化,开展复氧试验研究阶梯深潭结构和沙洲对溶解氧的影响,并取样分析大型底栖无脊椎动物的沿程分布。结果表明,流速对水温与溶解氧日变化规律无明显影响。试验河段水温和溶解氧恢复很快,经过17 km的河段,水温从123℃升高至300℃,且溶解氧饱和度基本达到饱和。河宽对水温恢复起重要作用,对溶解氧影响较小,对复氧速度基本无影响。流量通过改变淹没程度影响阶梯深潭的复氧能力。溶解氧在沙洲下游存在横向分布,滞水区溶解氧高于左右汊道。溶解氧是水库下游水生态的控制因素,物种多样性随溶解氧的升高而增加  相似文献   
166.
A fungal perspective on conservation biology   总被引:1,自引:0,他引:1       下载免费PDF全文
Hitherto fungi have rarely been considered in conservation biology, but this is changing as the field moves from addressing single species issues to an integrative ecosystem‐based approach. The current emphasis on biodiversity as a provider of ecosystem services throws the spotlight on the vast diversity of fungi, their crucial roles in terrestrial ecosystems, and the benefits of considering fungi in concert with animals and plants. We reviewed the role of fungi in ecosystems and composed an overview of the current state of conservation of fungi. There are 5 areas in which fungi can be readily integrated into conservation: as providers of habitats and processes important for other organisms; as indicators of desired or undesired trends in ecosystem functioning; as indicators of habitats of conservation value; as providers of powerful links between human societies and the natural world because of their value as food, medicine, and biotechnological tools; and as sources of novel tools and approaches for conservation of megadiverse organism groups. We hope conservation professionals will value the potential of fungi, engage mycologists in their work, and appreciate the crucial role of fungi in nature. Una Perspectiva Micótica de la Biología de la Conservación  相似文献   
167.
Advocates of community-based approaches to environmental management argue that by respecting local circumstances, skills, and concerns we may improve the prospects of achieving environmental sustainability; yet, within nation states such as Canada, environmental conditions, management and enforcement costs and capabilities, and power differentials within and among civic and public sectors may result in a highly differentiated capacity for environmental management across different localities and regions. This article draws on insights of political ecology to 1) create a conceptual framework that identifies key elements shaping regional environmental management regimes and to 2) undertake a comparative analysis to assess how elements interact to generate uneven management outcomes. I compare experiences of two Canadian biosphere reserves designated in 2000: Clayoquot Sound, BC; and Redberry Lake, SK. Analysis reveals that differences in governance and institutional capacities in the biosphere reserves are key to explaining uneven local outcomes. Where the public and civic sectors are strong, a robust and publicly vetted form of management will emerge. Where these sectors are weak and land is held as private property, environmental nongovernmental organizations can set the type and level of management, to the exclusion of effective civic and state involvement. This result may improve environmental sustainability but hinder social sustainability of a management regime and raises questions about the efficacy of community-based management.  相似文献   
168.
This paper examines predictors of vegetative cover on private lands in Baltimore, Maryland. Using high-resolution spatial data, we generated two measures: “possible stewardship,” which is the proportion of private land that does not have built structures on it and hence has the possibility of supporting vegetation, and “realized stewardship,” which is the proportion of possible stewardship land upon which vegetation is growing. These measures were calculated at the parcel level and averaged by US Census block group. Realized stewardship was further defined by proportion of tree canopy and grass. Expenditures on yard supplies and services, available by block group, were used to help understand where vegetation condition appears to be the result of current activity, past legacies, or abandonment. PRIZM™ market segmentation data were tested as categorical predictors of possible and realized stewardship and yard expenditures. PRIZM™ segmentations are hierarchically clustered into 5, 15, and 62 categories, which correspond to population density, social stratification (income and education), and lifestyle clusters, respectively. We found that PRIZM 15 best predicted variation in possible stewardship and PRIZM 62 best predicted variation in realized stewardship. These results were further analyzed by regressing each dependent variable against a set of continuous variables reflective of each of the three PRIZM groupings. Housing age, vacancy, and population density were found to be critical determinants of both stewardship metrics. A number of lifestyle factors, such as average family size, marriage rates, and percentage of single-family detached homes, were strongly related to realized stewardship. The percentage of African Americans by block group was positively related to realized stewardship but negatively related to yard expenditures.  相似文献   
169.
Many problems and challenges of ecosystem management currently are driven by the rapid pace and spatial extent of landscape change. Parks and reserves within areas of high human population density are especially challenged to meet the recreational needs of local populations and to preserve valued environmental resources. The complex problem of managing multiple objectives and multiple resources requires an enormous quantity of information, and conceptual models have been proposed as tools for organizing and interpreting this information. Academics generally prefer a bottom-up approach to model construction that emphasizes ecologic theory and process, whereas managers often use a top-down approach that takes advantage of existing information to address more pragmatic objectives. The authors propose a formal process for developing, applying, and testing conceptual models to be used in landscape monitoring that reconciles these seemingly opposing perspectives. The four-step process embraces the role of hypothesis testing in the development of models and evaluation of their utility. An example application of the process to a network of national parks in and around Washington, DC illustrates the ability of the approach to systematically identify monitoring data that would both advance ecologic theory and inform management decisions.  相似文献   
170.
Recent “green” planning initiatives envision food production, including urban agriculture and livestock production, as desirable elements of sustainable cities. We use an integrated urban political ecology and human–plant geographies framework to explore how foraging for “wild” foods in cities, a subversive practice that challenges prevailing views about the roles of humans in urban green spaces, has potential to also support sustainability goals. Drawing on research from Baltimore, New York City, Philadelphia, and Seattle, we show that foraging is a vibrant and ongoing practice among diverse urban residents in the USA. At the same time, as reflected in regulations, planning practices, and attitudes of conservation practitioners, it is conceptualised as out of place in urban landscapes and an activity to be discouraged. We discuss how paying attention to urban foraging spaces and practices can strengthen green space planning and summarise opportunities for and challenges associated with including foragers and their concerns.  相似文献   
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