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371.
The attitudes and behaviours of private landholders toward the conservation of a highly transformed and critically endangered habitat, Overberg Coastal Renosterveld (OCR) (a grassy shrubland of the Cape Floral Region, South Africa) are described. Personal, semistructured interviews were conducted with landholders, representing 40 properties in the Overberg region, on topics such as management and utilisation of OCR, the depth of their knowledge of its conservation importance, what they perceive its value to be, and the extent of their willingness to conserve it. General attitudes toward conservation incentives and provincial conservation authorities were also investigated. Farmers more willing to conserve were younger, did not necessarily have a better education, and owned larger farms (>500 ha) with a greater amount of remnant renosterveld (>300 ha) than those less willing to conserve. Attitudes toward the OCR were largely negative, related to associated problem plants and animals and the fact that it is believed not to be economically advantageous to retain it. However, farmers are of the opinion that provision of incentives and increased extension support will provide practical positive inducements for conservation. Landholder education is paramount to prevent further transformation of critically endangered habitats. The success of private-conservation programs depends on the attitudes of landowners toward (1) the particular habitat or species to be conserved (which can vary depending on the type of land use practised and the associated benefits and disadvantages of that habitat type); (2) the conservation agency or extension officers responsible for that area; and (3) willingness of landowners to participate in a conservation program, which is influenced by landowner age, farm size, and the amount of natural habitat left to conserve.  相似文献   
372.
泥石流堵河影响因素研究——以岷江上游为例   总被引:6,自引:0,他引:6  
张金山  沈兴菊  谢洪 《灾害学》2007,22(2):82-86
以岷江上游为研究区,选取堵河型泥石流沟4条、堵塞型和不堵河型泥石流沟各2条,在详细分析和比较8条典型泥石流的流域特征、一次有代表性的泥石流过程的泥石流流体特征及沟口处主河特征的基础上,结合专家问卷调查,得出了与泥石流堵河关系较为密切的因素,它们是:泥石流规模、堆积区主河宽度、泥石流沟床比降、泥石流流量、入汇处主河流量、泥石流颗粒级配、入汇处主河比降、泥石流粘度、重度、泥石流沟与主河夹角、泥石流暴发频率等。  相似文献   
373.
- DOI: http://dx.doi.org/10.1065/espr2006.02.294 Background, Aim and Scope. To better address the requirements of the changing multilateral order, the United Nations Industrial Development Organization (UNIDO) Cleaner Production Programme, in 2004, developed the new Sustainable Industrial Resource Management (SIRM) approach. This approach is in accordance with the principles decided at the United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro, Brazil in 1992. Unlike the traditional approaches to environmental management, the SIRM concept captures the idea of achieving sustainable industrial development through the implementation of circular material and energy flows in the entire production chain and reduction of the amount of material and energy used with greater efficiency solutions. The SIRM approach seeks to develop new models to encourage a shift from selling products to supplying services, modifying, in this manner, the supplier/user relationship and resulting in a win-win situation for the economy and the environment. Chemical Leasing represents such a new service-oriented business model and is currently being promoted by UNIDO′s Cleaner Production Programme. Main Features. One of the potential approaches to address the problems related to ineffective use and over-consumption of chemicals is the development and implementation of Chemical Leasing business models. These provide concrete solutions to the effective management of chemicals and on the ways negative releases to the environment can be reduced. The Chemical Leasing approach is a strategy that addresses the obligations of the changing international chemicals policy by focusing on a more service-oriented strategy. Mexico is one of the countries that were selected for the implementation of UNIDO's demonstration project to promote Chemical Leasing models in the country. The target sector of this project is the chemical industry, which is expected to shift their traditional business concept towards a more service and value-added approach. This is being achieved through the development of company specific business models that implement the above-indicated Chemical Leasing concept with the support from the Mexican National Cleaner Production Centre (NCPC). Results and Conclusions. The implementation of Chemical Leasing in Mexico has proven to be an efficient instrument in enhancing sustainable chemical management and significantly reducing emissions in Mexico. Several companies from the chemical industrial sector implement or agreed to implement chemical leasing business models. Based on the positive findings of the project, several Mexican companies started to negotiate contents of possible Chemical Leasing contracts with suitable business partners. The project further aimed at disseminating information on Chemical Leasing. It successfully attracted globally operating companies in the chemicals sector to explore possibilities to implement Chemical Leasing business models in Mexico. At the international level, the results of the UNIDO project were presented on 20TH September 2005 during a side event of the Strategic Approach to International Chemicals Management (SAICM) Preparation Conference in Vienna. Recommendations and Outlook. To facilitate the promotion and application of Chemical Leasing project at international level, UNIDO is currently developing a number of tools to standardize Chemical Leasing projects. These include, among others, Chemical leasing contract models; Chemical Leasing data base to find partners for chemical leasing; and guidelines to implement Chemical Leasing projects and work programmes.  相似文献   
374.
针对现行公务员录用分配制度存在的问题,通过细致的分析,探讨关于公务员录用分配的最佳策略.决策过程中以应聘者能力与各部门要求的偏差为标准,建立模型,且考虑所有应聘者的意愿时,分三种情况进行讨论:都服从志愿调配;都不服从志愿调配;既有服从调配的、又有不服从志愿调配的,使模型更接近实际情况.  相似文献   
375.
Glyphosate-based herbicides are extensively used in Argentina's agricultural system to control undesirable weeds. This study was conducted to evaluate the culturable mycobiota [colony forming units (CFU) g?1 and frequency of fungal genera or species] from an agricultural field exposed to pesticides. In addition, we evaluated the tolerance of A. oryzae and nontoxigenic A. flavus strains to high concentrations (100 to 500 mM – 17,000 to 84,500 ppm) of a glyphosate commercial formulation. The analysis of the mycobiota showed that the frequency of the main fungal genera varied according to the analyzed sampling period. Aspergillus spp. or Aspergillus section Flavi strains were isolated from 20 to 100% of the soil samples. Sterilia spp. were also observed throughout the sampling (50 to 100%). Aspergillus section Flavi tolerance assays showed that all of the tested strains were able to develop at the highest glyphosate concentration tested regardless of the water availability conditions. In general, significant reductions in growth rates were observed with increasing concentrations of the herbicide. However, a complete inhibition of fungal growth was not observed with the concentrations assayed. This study contributes to the knowledge of culturable mycobiota from agricultural soils exposed to pesticides and provides evidence on the effective growth ability of A. oryzae and nontoxigenic A. flavus strains exposed to high glyphosate concentrations in vitro.  相似文献   
376.
杜兴信 《灾害学》1996,11(3):58-59
介绍了1995年日本阪神7.2级地震造成的河流损害、防止次生灾害采取的紧急对策及修复方案,以供我国研究防御地震次生灾害参考。  相似文献   
377.
Nine sites on streams in the Platte River Basin in central Nebraska were sampled as part of the US Geological Survey's National Water-Quality Assessment Program during 1993–1994. A combination of canonical correspondence analysis and an index of biotic integrity determined from fish community data produced complementary evaluations of water-quality conditions. Results of the canonical correspondence analysis were useful in showing which environmental variables were significant in differentiating fish communities at the nine sites. Five environmental variables were statistically significant in the analysis. Median specific conductance of water samples collected at a site accounted for the largest amount of variability in the species data. Although the percentage of the basin as cropland was not the first variable chosen in a forward selection process, it was the most strongly correlated with the first ordination axis. A rangeland-dominated site was distinguished from all others along that axis. Median orthophosphate concentration of samples collected in the year up to the time of fish sampling was most strongly correlated with the second ordination axis. The index of biotic integrity produced results that could be interpreted in terms of the relative water quality between sites. Sites draining nearly 100% cropland had the lowest scores for two individual metrics of the index of biotic integrity that were related to species tolerance. Effective monitoring of water quality could be achieved by coupling methods that address both the ecological components of fish communities and their statistical relationships to environmental factors.  相似文献   
378.
The concept of water conservation has increased in importance because of revisions in the rules and procedures for performing cost-benefit analyses of federal water projects. These revisions include a requirement that nonstructural and water conservation measures be incorporated into economic assessments of projects. Project analyses will now proceed as if water supplies were allocated “most effectively,” that is, to their highest valued uses. A related requirement provides that the net benefits of any project should now be valued using willingness to pay measures. A specific cost-benefit methodology accommodating the revisions is constructed and discussed. Informational requirements for applying this methodology are identified. In addition to being consistent with federal mandates, this technique offers important advantages over the traditional “requirements” approach to water supply planning.  相似文献   
379.
对“撞了白撞”问题的思考   总被引:1,自引:1,他引:1  
在《中华人民共和国道路交通安全法》公布前后有关“撞了白撞”被否决的宣传对交通安全不利。“撞了白撞”的演绎存在片面性 ,“撞了白撞”被否决的宣传不符合自然科学规律 ,存在理论上的误区。人们应该清楚的认识到 :获得交通事故损害赔偿并非获得了交通安全保障 ;行人、非机动车等交通“弱者”在一定条件下可转化为交通“强者”。对法律、法规的宣传 ,既要讲究法律原则和社会道德准则 ,也要讲究科学性。  相似文献   
380.
退耕还林还草、进行生态环境建设是我国政府制定的一项战略性措施。伊犁河谷需要退耕还草的面积为14.13×104hm2,河谷自然地理条件较复杂,不同地域水、土、光、热条件差异较大,本文就伊犁河谷不同地域退耕还草的模式、生态经济效益及相关技术问题进行了探讨。  相似文献   
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