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821.
The coupling relation exists in water and soil conservation and economic-social development. The article analyses the relation of soil and water conservation and economic-social development stages as well as the coupling analytical method. Then calculates the expecting income by dispersing Markov decision and calculates the correlation coefficient and the relationship degree. The article obtains the relationship of soil and water conservation investments and all kinds of incomes. Finally, it analyzes the important meaning in socio-economic development of water and soil conservation.  相似文献   
822.
Energy efficiency and conservation for individual Americans   总被引:1,自引:0,他引:1  
Americans make up only 4% of the world population, yet currently consume 25% of the world’s fossil fuels. The U.S. imports 63% of its oil and it is predicted that by 2020 the U.S. will be importing 95% of its oil resources. Over the past century, ample and affordable supplies of fossil fuels have powered the growth and prosperity of the economies of the US and other countries. Within this century, world oil supplies will decline while demand is projected to continue to increase, suggesting that we will have to transition to different fuels or become much more energy efficient or both. Looking ahead to the near decades, estimates are that consumers will have to reduce their energy use by at least 50%. This reduction will be necessary in large part due the decline in the availability of conventional oil and gas, but also because the U.S. population will continue to grow in number. Although government action is important, individuals too often discount their ability to make significant contributions to solving such major problems. This investigation identifies how informed and concerned individuals can collectively conserve fossil energy. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. An erratum to this article can be found at  相似文献   
823.
The Miombo, the most extensive tropical woodland formation of Africa directly supports the livelihoods of over 100 million people through the provision of many tree products and ecosystem services essential to both the rural and urban communities. While the destruction of the Miombo has often been blamed on the rural communities dwelling near the forest resources, many urban dwellers depend heavily on the various products derived from the woodlands. This paper highlights the importance of the Miombo in the livelihoods of rural people, the potential threats to this ecosystem and opportunities for its sustainable management. About 70% of energy consumed in southern Africa is in the form of fuelwood or charcoal. The economic importance of the Miombo especially from non-timber forest products (NTFPs) is usually understated due to their perceived non-economic value yet they play an important role in sustaining livelihoods of forest dependent people in the miombo ecoregion. The Miombo also contributes to health services through the use of medicinal plant and products, in some cases, contributing up to 80% to rural health, including helping in coping with effects of HIV/AIDS, malaria and several diseases. The possibility of developing payment for environmental services schemes through public–private partnerships, and community-based sustainable management models are proposed. Through conservation and commercialization of some of the products and services, there is a potential to provide income and improve the livelihood of people involved in the trade along the value chain.  相似文献   
824.
In seeking to determine whether climate change mitigation strategies are effective, researchers and policy-makers typically use energy consumption as an indicator. UK government data show that energy use amongst the public is rising, despite measures to encourage energy conservation. Yet, research to date has not explicitly asked which actions the public are taking with the express intention of mitigating climate change. Using Stern's classification of impact-oriented and intent-oriented behaviour research, the research described in this paper examines both actions taken ‘out of concern for climate change’ and energy conservation practices amongst the UK public. The findings show a clear divergence between actions prescribed by policy-makers (i.e. energy conservation) and those taken by the public to mitigate climate change (e.g., recycling). Furthermore, those who take action to conserve energy generally do so for reasons unconnected to the environment (e.g., to save money). Regression analyses highlight the distinct determinants of these two behavioural categories. These findings imply that surveys using energy reduction as an indicator of public response to climate change falsely assume that these can be equated; consequently, they will provide a distorted picture of behavioural response. Possible reasons for the asymmetry of intentions and impacts, and policy implications, are discussed.  相似文献   
825.
Potential for rainwater use in high-rise buildings in Australian cities   总被引:1,自引:0,他引:1  
Rainwater is a traditional but underutilized water resource that has today had a resurgence due to the worldwide water crisis. This paper demonstrates the outcomes of research on the feasibility of rainwater use in high-rise residential envelopes for four Australian cities of Melbourne, Sydney, Perth and Darwin. Different climate patterns and various levels of water demand management were established for determination of storage dimensions; annual tank water use; reduction in both imported water flow and stormwater disposal; and water spillage from tanks. High level water demand management was a profoundly effective tool for reducing potable water supply, especially in combination with rainwater use. The economic feasibility of rainwater use systems were estimated; with Sydney having the shortest payback period compared to other cities either both with 3A rated appliances (8.6 years) or 5A ones installed (10.4 years). That was due to the higher and more consistent rainfall in Sydney. An outcome of this study was that Sydney was likely most suited to rainwater use, followed by Perth, Darwin, and then Melbourne. The objective of this study was to fill in the gap in estimating feasibility of rainwater use in various Australian cities. This investigation endeavors to provide assistance to water authorities and urban planners of Australian cities with the consideration of the potential of rainwater harvesting.  相似文献   
826.
Establishment of plans for environmental planning and management requires that a number of natural and societal factors must be taken into consideration. Insights into the inherent dynamics of nature as well as the role that past human activities have played for establishing the current condition of the landscape and the natural environment in general are essential. Many natural and man-made changes occur over time scales of decades or centuries, and these are difficult to comprehend without a historical perspective. Such a perspective can be obtained using palaeoecological studies, i.e. by geochemical and biological analyses of lake sediment and peat deposits. To illustrate the long-term dynamics of nature and particularly the role of man, we present here five case studies from Sweden concerning pollution, lake acidification, lake eutrophication, biodiversity, and landscape dynamics and conservation – topics of broad interests – and discuss benefits of including a longer time perspective in environmental management.  相似文献   
827.
Group-based approaches to the elicitation of stated preferences are considered particularly suitable for valuing unfamiliar or complex environmental goods. While such exercises provide participants with detailed information and time to think and deliberate, they require a considerable degree of motivation from the respondents. Effects of motivation on willingness to pay (WTP) tend to be ignored within the valuation research community, although similar effects have been reported in psychological literature. In this study, a novel approach using video recordings and behaviour coding of participants in group-based Market Stall meetings was employed to measure motivation as well as its impact on WTP and the theoretical and convergent validity of stated WTP. Indicators of motivation correlated significantly with both WTP statements and their validity, with more motivated individuals stating higher and more valid bids. These findings suggest that the recognition of motivation is an important novel element of research into stated preferences, particularly with respect to usefulness and quality of WTP measures.  相似文献   
828.
湖南省水土流失及其危害   总被引:1,自引:0,他引:1  
贺建林 《生态环境》2000,9(4):266-269
目前湖南省水土流失面积已由50a前的1.87万km2增加为4.40万km2,占全省土地总面积的20.8%。水土流失为中等以上的县市占全省的比例达到了60%。湖南省水土流失以面蚀为主,水土流失日趋严重。水土流失主要有以下危害降低土壤肥力,加剧旱洪灾害尤其是湖区的洪涝灾害,降低水利工程效益和阻碍水上交通。由此可见,水土保持工作不仅关系到湖南山区的经济发展和广大山区人民的脱贫致富,还关系到保护环境、资源和洞庭湖区的长治久安问题。  相似文献   
829.
Many current wildlife conservation efforts in Africa focus on providing local communities with economic incentives to utilize wildlife as a form of land use in order to achieve the twin goals of ecological preservation as well as sustainable human economic development. Tanzanian Maasailand is home to some of the greatest concentrations of large mammals remaining outside National Parks and reserves, as well as a uniquely traditional human culture in the form of the Maasai themselves. Both are increasingly threatened by a variety of factors; poaching and habitat loss for wildlife, and the increasing marginalization of their pastoralist economy with regards to the Maasai. The fundamental cause of declining wildlife populations and biodiversity loss is that the Maasai have little economic or social interest in wildlife due to centralized management and financial benefits which are directed primarily to the Tanzanian state. Maasai pastoralism is highly compatible with wildlife, and the potential for the local communities to sustainably manage and benefit from this resource is promising. However, implementation of effective community-based natural resource management in the area faces political, cultural, and economic obstacles which will be critical in determining the outcomes of both conservation and community development efforts in Maasailand.  相似文献   
830.
论节能技术创新制度   总被引:1,自引:1,他引:0  
节能根据节能途径不同可分为结构节能、管理节能和技术节能三种。其中技术节能潜力巨大。文章试图通过完善节能技术创新制度推动我国技术节能工作。  相似文献   
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