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81.
Delivering on the Promise of Agroforestry   总被引:1,自引:0,他引:1  
Agroforestry – the traditional practice of growing trees on farms for the benefit of the farm family and for the environment – was brought from the realm of indigenous knowledge into the forefront of agricultural research less than two decades ago. It was promoted widely as a sustainability-enhancing practice that combines the best attributes of forestry and agriculture. Based on principles of natural resource management and process-oriented research, agroforestry is now recognized as an applied science, that is instrumental in assuring food security, reducing poverty and enhancing ecosystem resilience at the scale of thousands of smallholder farmers in the tropics.Trees on farms provide both products and services: they yield food, fuelwood, fodder, timber and medicines, which farm families can use at home or take to market to bring in much-needed cash; they replenish organic matter and nutrient levels in soils and they help control erosion and conserve water. The International Centre for Research in Agroforestry, and its partners, are working to integrate the functions of trees with policy and institutional improvements that aim at facilitating wide-scale adoption by farmers.Two examples described in this paper are replenishing soil fertility in sub-Saharan Africa using short-term improved tree and shrub fallows and the results of agroforestry research to support significant land tenure policy in southeast Asia.Although just one option in sustainable land-use, science-based agroforestry has the potential to produce economically, socially and environmentally sound results for the billions of people who depend on this ancient practice and modern science.  相似文献   
82.
对灾害研究中几个问题的思考   总被引:2,自引:1,他引:1  
单修正 《灾害学》1999,14(4):85-89
对灾害研究中有关的几个问题进行了探讨。认为: 灾害学是最重要的自然社会科学; 人文灾害比自然灾害更具毁灭性; 研究人文灾害中的公路交通事故、核战争问题、人口问题、环境污染问题等具有重要的现实意义和深远的历史意义。  相似文献   
83.
Poverty Reduction and Sustainable Development   总被引:3,自引:0,他引:3  
The prominent place of the chapter on poverty in the Johannesburg Plan of Implementation (JPI) is totally in keeping with the priority given to poverty reduction in the development thinking of the international community of today. The Johannesburg process did not lead to any new insights or new commitments in the fight against poverty. Section one sets out a factual comparison of the poverty chapters in Rio's Agenda 21 (AG21) and in the JPI. Section two reviews the conceptual links between poverty reduction and sustainable development, since poverty is used both as a dependent and as an independent variable. This analysis shows a shift in the function of growth as related to environmental protection. Section three explores the naturalization of development thinking in its economic and social dimensions and shows how this affects the policy options for social protection. I also explain how social and environmental sustainability have become elements of risk management and how are both aimed at conflict prevention and enhanced growth. Finally, in section four three lines of action are suggested to enhance the emergence of a socially meaningful sustainable development agenda that, ideally, would make poverty reduction strategies redundant.  相似文献   
84.
The Akosombo dam was constructed on the Volta river primarily for the generation of hydropower. The resultant Volta lake which was formed between 1962 and 1966 in Ghana will probably long be one of the greatest man-made lakes. It produces 912MW of electricity at its maximum operating capacity. The Akosombo hydroelectric project (HEP) was meant among others to open up Ghana to rapid industrialization and hence modern development. Other positive impacts of the HEP include fishing, farming, transportation and tourism. However, there are equally negative impacts, some of which the project did not envisage and these are felt on the physical, biological and human subsystems within the immediate project environments and places much more distant from them. Recently, there have been declines in the lake levels resulting most probably from inadequate rainfall and/or runoff from the river catchments that feed the lake, and also from the observed rising temperatures. Comparisons of the runoff from two most important tributaries of the Volta (White Volta and Oti) for two time periods of 1951–1970 and 1971–1990 showed reductions in mean streamflows of 23.1% on the White Volta and 32.5% on the Oti. Similarly, a plot of the mean annual temperatures for the upper Volta basin indicated a 1^C rise in temperature from 1945–1993.  相似文献   
85.
根据中国道路交通事故经济损失的研究现状,借鉴国外对道路交通事故经济损失研究的成功经验,提出适用于中国实际情况的交通事故社会公共机构服务损失费用构成;确定了道路交通事故社会公共机构服务损失评价指标体系。基于经济学和统计学理论,主要从警方服务、清障服务、管理部门服务和法律诉讼服务4个方面对道路交通事故社会服务损失进行了深层次理论分析与评价;构建了相应的评价计量模型;提出了我国评价交通事故社会服务损失的一些合理化建议。研究结果对科学、全面、合理地评价道路交通事故社会经济损失具有重要的实际意义。  相似文献   
86.
87.
ABSTRACT: Decisionmaking associated with the Nation's 1.7 billion acres of forest and range land has become increasingly complicated because of the rise in competition for resource use and in the awareness of environmental and social effects. This system analysis approach uses four models to synthesize pertinent masses of information into measures of economic, environmental, and social impacts. The system results can be used to help evaluate alternative national programs. The models are:
88.
ABSTRACT: For many years, Federal water resources projects have been subjected to benefit-cost analysis to establish their economic feasibility. Several years ago social well-being was added as a consideration. This paper discusses the state-of-the-art in analyzing and evaluating aspects of social well-being. It stresses current short-falls and advocates a direction for further efforts.  相似文献   
89.
ABSTRACT: Increased irrigation as a means of achieving economic development can impose significant social costs on the state or region of growth. The growth in population induced by additional irrigation will require new roads, water and sewage facilities, schools, fire and police protection, etc. Also the increased energy demands due to irrigation and growth in economic activity must be met. Capital investments required to service these needs of new development can become very large. This study attempts to measure such social overhead costs or irrigation development for some specific irrigation project areas of Eastern Washington. It is shown that investment costs in overhead items can reach $2,000 per acre irrigated or $70,000 per job created. Alternatively, the annual costs can equal $180 per acre or $6,700 per worker. These costs must be paid locally through increased taxes, utility rates, or costs for services.  相似文献   
90.
ABSTRACT: Participation in water-based recreation activities does not arise in random fashion nor simply as a result of having a water resource immediately available. Neither do individuals and groups engage in the same activities or a specific activity in the same way. The purpose of the present paper is to describe an alternative framework whereby differences among recreation users can be identified. Prior to this time, research directed toward understanding participation patterns at a recreational site have emphasized the activities while ignoring the human behavior factors which determine how participation arises. People consider recreation sites to be leisure settings in which the definition of such places has a broader socio-cultural meaning than that the site was designed. These definitions are reflected within the context of the social group and can be observed in the subsequent orientation to leisure and play. When activities are considered in the context of a human group, differences in participation patterns can be discovered.  相似文献   
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