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381.
党的十五大提出发展多种形式的公有制经济,在这种新形势下,环境管理如何转轨,本文进行了探讨和研究。  相似文献   
382.
论湘中城市群经济的融合耦动与可持续发展   总被引:3,自引:0,他引:3  
本文以湘中(长株潭)城市群作为研究对象,概述了湘中城市群经济融合的总体特征,对其城市群空间生长演化过程中存在的问题和应采取的对策,经济如何实现可持续发展进行了探讨。  相似文献   
383.
A study of the impact of two agroecological development programs in central America was conducted in 1994, five years and fifteen years after the programmes had ended. Yields of maize and beans being achieved by those farmers involved in each program were, on the average, more than seven times the yields being achieved at the time of program initiation. Increases in yields and incomes were achieved through the use of a large number of innovations, involving especially soil retention measures, purchased organic matter, intercropped green manure/cover crops, natural pest control, crop diversification and crop rotations. Use of chemical fertilizer was reduced, herbicides avoided almost entirely, and several substitutes for pesticides are now used. These technologies, plus more recent innovations such as microscale water harvesting and precision planting, should enable small farmers around the world to increase productivity enough that the world can avoid major hunger over the next 30 years, without increasing substantially, if at all, the world's use of chemical inputs.  相似文献   
384.
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   
385.
论城市灾害管理模型   总被引:8,自引:1,他引:7  
城市是人类抗灾,防灾的重点,加强城市灾害防治是城市,乃至整个国家可持续发展的必要保证,城市灾害管理是减轻城市灾害的主要的主要措施之一,本文用管理学,控制论,决策论的思想建立了城市灾害管理的模型。  相似文献   
386.
刘艺林 《灾害学》1999,14(4):65-70
概述了青岛市基础设施现状; 介绍了青岛市主要自然灾害(气象、地震) 特别是90 年代以来重要灾情, 并分析了特征; 最后给出了结论和建议。  相似文献   
387.
ABSTRACT

Public participation in the form of public meetings and written submissions has been criticised as a democratic ritual that fails to give citizens a real voice in government decisions. Participatory mapping and community surveys are alternative public participation (PP) methods that can augment legally required processes for land use planning. To date, there has been little evaluation research comparing the information content generated by required PP processes and alternative PP sources with respect to local land use decisions. Using multiple development projects from a case study community, we analysed and compared information generated from three different sources of public participation: (1) formal public comment (written submissions), (2) responses to community survey questions, and (3) land use preferences generated from participatory mapping. We found public comment strongly supported development while results from survey questions and participatory mapping methods revealed community ambivalence. The differences in public opinion are attributed to two key factors: the representativeness of participants in the PP process and the specific methods used for measuring public opinion. Community surveys and participatory mapping generated more accurate and representative community information compared to the formal PP process which was characterised by lower participation and vulnerability to special interest manipulation. For local government decision makers, the political risk of broadening PP information appears high relative to the risk of inaccurately assessing public opinion thus limiting adoption of alternative PP methods such as participatory mapping.  相似文献   
388.
随着非道路移动机械保有量与使用量的不断增加,其排放造成的环境问题日益严重,相关的防治策略研究亟待加强。本研究首先总结了中国与欧美对非道路移动机械类型的划分方式及标准;其次,对中国与欧美的非道路移动机械排放标准进行归纳;最后,对现行中国与欧美的非道路移动机械排放标准进行了全面对比分析,分析发现,国内标准与欧美标准之间仍存在显著差距,以期为国内制定科学的非道路移动机械排放标准提供参考,为污染物防治策略的制定提供理论支撑。  相似文献   
389.
基于证书权威(CA)中心的时间戳服务系统的实现   总被引:5,自引:3,他引:2  
介绍了数字签名不具有抗抵赖的问题 ,以及数据抗抵赖在信息安全中的重要性。在对原有的时间戳协议缺乏可靠的身份认证和可信性分析后 ,提出了一种新的基于证书权威 (CA)中心的时间戳服务协议。利用CA中心的信任原理和数字证书的身份认证作用 ,使提供时间戳服务的服务方具备了可靠的身份鉴别和可信性。并利用XML标记对时间戳的数据内容进行描述 ,形成简单、直观的时间戳 ,且无需复杂的编解码过程。通过正确和可信的时间戳可以判定用户数据产生的时间 ,防止用户事后的抵赖行为 ,为网络应用提供更为安全的数据。  相似文献   
390.
Young H  Taylor A  Way SA  Leaning J 《Disasters》2004,28(2):142-159
This article examines the recent revision of the Sphere Minimum Standards in disaster response relating to food security, nutrition and food aid. It describes how the revision attempted to incorporate the principles of the Humanitarian Charter, as well as relevant human rights principles and values into the Sphere Minimum Standards. The initial aim of the revision was to ensure that the Sphere Minimum Standards better reflected the principles embodied in the Humanitarian Charter. This was later broadened to ensure that key legal standards and principles from human rights and humanitarian law were considered and also incorporated, in part to fill the "protection gap" within the existing standards. In relation to the food security, nutrition and food aid standards, it was agreed by participants in the process that the human right to adequate food and freedom from hunger should be incorporated. In relation to more general principles underlying the Humanitarian Charter, itself drawn largely from human rights and humanitarian law, it was agreed that there was a need to strengthen "protection" elements within the standards and a need to incorporate the basic principles of the right to life with dignity, non-discrimination, impartiality and participation, as well as to explore the relevance of the concept of the progressive realisation of the right to food. The questions raised in linking rights to operational standards required thought, on the one hand, about whether the technical standards reflected a deep understanding of the values expressed within the legal instruments, and whether the existing standards were adequate in relation to those legal rights. On the other hand, it also required reflection on how operational standards like Sphere could give concrete content to human rights, such as the right to food and the right to be free from hunger. However, there remain challenges in examining what a rights-based approach will mean in terms of the role of humanitarian agencies as duty-bearers of rights, given that the primary responsibility rests with state governments. It will also require reflection on the modes and mechanisms of accountability that are brought to bear in ensuring the implementation of the Minimum Standards.  相似文献   
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