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521.
A strategy for management of giant sequoia groves is formulated using a conceptual framework for ecosystem management recently developed by Region Five of the USDA Forest Service. The framework includes physical, biological, and social dimensions. Environmental indicators and reference variability for key ecosystem elements are discussed in this paper. The selected ecosystem elements include: 1) attitudes, beliefs, and values; 2) economics and subsistence; 3) stream channel morphology; 4) sediment; 5) water; 6) fire; 7) organic debris; and 8) vegetation mosaic. Recommendations are made for the attributes of environmental indicators that characterize these elements. These elements and associated indicators will define and control management activities for the protection, preservation, and restoration of national forest giant sequoia ecosystems.  相似文献   
522.
天津城市自然灾害及其对策的初步研究   总被引:1,自引:0,他引:1  
本文初步分析和研究了天津市近百年来的10余种城市自然灾害的特征与成因,指出随着城市化的发展,相应地必须加强城市自然灾害的对策研究,并结合天津市实际情况,提出初步的对策方案。  相似文献   
523.
孙昭民  魏光兴 《灾害学》1995,10(3):57-63
本文通过发生于山东省境内的各种主要自然灾害的分析,给出山东省主要自然灾害类型,结合山东省的自然地理、地质等特征,对自然灾害的区域分布进行了初步综合分区。  相似文献   
524.
Available estimates of potentially recoverable world mineral and fuel resources are examined with a view to determining whether everyone likely to be living on earth next century could be raised to the material living standards people in developed countries now have. It is concluded that this goal is impossible. A number of fundamentally important implications follow, especially regarding the inappropriateness of growth strategies in general, goals for Third World development, and the need for ‘de-development’ of developed countries to much more frugal, self-sufficient and cooperative social systems.  相似文献   
525.
The surveillance of communicable diseases after a natural disaster reflects the permanent state of effectiveness of the health services and the adverse factors of the natural, physical and family environments. Diarrhoeal diseases may be the best indicator of a community's period of recovery. The return of these diseases to endemic levels means that the pre-disaster situation has been reestablished.  相似文献   
526.
The separate effects of 50% increases in the prices of energy, renewable and nonrenewable natural resource inputs on factor demands and production costs are simulated for Canadian total manufacturing and six two-digit industries. Both renewable and nonrenewable natural resource price increases have a substantially greater effect upon the demands for other factors and upon production costs than a parallel energy price increase. These results are important from a policy perspective and justify the further disaggregation of inputs in this and in other models of input demand.  相似文献   
527.
A variety of species was observed as either visitors, permanent, or summer residents on surface mines with different ecological adaptations. Passerine species were the most prevalent of the 25 families represented. Bird communities as well as individual species were correlated with the structure and species of vegetation on the mines. The composition of the bird communities changed in response to successional vegetation stages from grassland to forest communities.  相似文献   
528.
Stakeholder participation is expected to improve the efficiency, equity, and sustainability of natural resource management research and development (R&D) projects by ensuring that research reflects users’ priorities, needs, capabilities, and constraints. Use of participatory methods and tools is growing rapidly; however, there is little systematic evidence about what participation actually means in practice, or about what difference it makes. Based on an inventory of 59 self‐described participatory R&D projects in the area of natural resource management, this article characterizes the typical project and analyzes how stakeholders are selected, how they participate in the research process, and what their involvement means for project costs and impacts. The results suggest that, while projects are generating a range of direct and indirect benefits for participants, more careful attention needs to be paid to achieving equitable impacts. Current practices may lag behind best practices in key areas, such as power sharing and participant selection, and may therefore be missing important contributions from women and other marginalized groups.  相似文献   
529.
中国城市灾害地学背景研究   总被引:10,自引:0,他引:10  
吴必虎  彭加亮 《灾害学》1997,12(1):28-33
根据特征致灾因子的差异,将中国城市灾害类型大体上划分为沿海台风暴雨洪涝地面沉降型、北方干旱缺水风沙地面沉降型和南方洪涝渍害地面沉陷塌陷型等三大类型区。分别用上海、北京、武汉作为三种案例地区,讨论了以上三种城市灾害类型区的主要灾害及其地学背景。指出除了自然地理的因素外,人类在城市灾害致灾因素中也通过开采地下水、设计防洪排涝设施等行为表现出一定程度的作用.  相似文献   
530.
本文在对自然灾害主要特征及我省主要灾害综合分析的基础上,结合我省灾情提出了减轻自然灾害的对策建议。  相似文献   
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