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231.
输电线路建设项目水土保持方案编制的几点认识   总被引:1,自引:0,他引:1  
针对输电建设项目的特点,阐述了输电线路与一般线形建设项目水土保持方案的不同之处,提出了输电线路水土保持方案编制的程序、内容及方法.  相似文献   
232.
Environmental pollution and degradation of ecosystems considerably affect the natural resources. The Turkish Government is aware of the importance of the preservation of natural ecology and thereby the environmental conservation of many species in their natural habitat. This paper provides critical assessments of the problems and possible solutions in the identification, implementation and management of the Specially Protected Areas (SPAs) system by giving basic information about stakeholders and their responsibilities that currently offer nature conservation in Turkey. The goals of the article are to analyze how the SPAs interface with the local people, especially the villagers who have dwelt there before SPA designation and how people-SPA conflicts resolved; to show how effective the SPA conservation objectives have been; to outline the significance of informing and empowering people in nature conservation for the protected area management and to show the importance of planning at all levels during protection of the natural, archeological and cultural values of the SPAs.  相似文献   
233.
Sub‐Saharan Africa continues to face the daunting challenge of alleviating poverty due to slow economic growth. In southern Africa, most countries are adopting policies that promote the integration of biodiversity conservation and rural development to contribute to rural poverty alleviation. Numerous approaches have been undertaken in this endeavour, including Transfrontier Parks (TFPs) and Transfrontier Conservation Areas (TFCAs). This paper discusses some of the limitations of the TFPs. In conclusion I posit that unlike TFPs, which are state controlled and managed, TFCAs, which promote multi‐land use and multi‐stakeholder participation are attainable and have a higher probability of sustaining biodiversity conservation and contributing to the alleviation of rural poverty, if: (i) areas of high biodiversity conservation within communal areas can be identified, zoned and leveraged to biodiversity conservation and managed in partnership between the communities and the private sector; (ii) local communities can secure legal rights to their customary land being devoted to biodiversity conservation and use such pieces of land as collateral in negotiating partnerships with the private sector in developing conservation‐based enterprises; (iii) functional community natural resource governance institutions can be established and empowered to represent their constituencies in securing fair equity from profits made from sustainable use of the conserved biodiversity assets and tourism businesses; (iv) concerted effort can be invested in developing and implementing family planning and fertility reduction strategies that would slow down human population growth to levels that can be sustained by the available natural resources; and (v) if sustainable financing mechanisms can be developed, and the governance of protected areas occurring in the TFCAs can be broadened to include other stakeholders.  相似文献   
234.
通过对钢铁行业消耗水资源及产生污染情况进行分析,阐述了目前钢铁行业为节能减排而采取的管理、技术、污染治理措施,以达到减少废水外排量、降低污染物浓度、降低新水消耗的目的,对钢铁行业废水回用中尚存和潜在的工艺、设计问题进行了讨论,同时提出了通过清洁生产、优化工艺结构来解决问题的措施和建议,确立了企业近期和长期的节能减排任务目标。  相似文献   
235.
Abstract: Thermoelectric power generation is responsible for the largest annual volume of water withdrawals in the United States although it is only a distant third after irrigation and industrial sectors in consumptive use. The substantial water withdrawals by thermoelectric power plants can have significant impacts on local surface and ground water sources, especially in arid regions. However, there are few studies of the determinants of water use in thermoelectric generation. Analysis of thermoelectric water use data in existing steam thermoelectric power plants shows that there is wide variability in unitary thermoelectric water use (in cubic decimeters per 1 kWh) within and among different types of cooling systems. Multiple‐regression models of unit thermoelectric water use were developed to identify significant determinants of unit thermoelectric water use. The high variability of unit usage rates indicates that there is a significant potential for water conservation in existing thermoelectric power plants.  相似文献   
236.
为了解听力防护用品使用过程中的问题,提高我国噪声暴露工人听力防护用品的使用率和有效率,选择噪声危害较大的某飞机维修公司的员工,进行听力防护用品使用情况的问卷调查。结果显示:该公司为员工提供耳塞和耳罩两种听力防护用品;员工的听力保护意识、使用情况较好,使用率达95%,但对听力防护用品相关知识的了解不够全面;能够在工作中一直坚持使用的工人较少,仅占11%,影响工人工作时间使用听力防护用品时间长短的因素主要是其舒适性。调查分析提示:在未来听力防护用品的生产过程中,需要进一步加强和改善舒适性的技术;政府、企业和个人3方面共同参与,降低职业性噪声暴露对工人听力的损伤。  相似文献   
237.
The authors investigated the ignitability of aluminium and magnesium dusts that are generated during the shredding of post-consumer waste. The relations between particle size and the minimum explosive concentration, the minimum ignition energy, the ignition temperature of the dust clouds, etc. the relation between of oxygen concentration and dust explosion, the effect of inert substances on dust explosion, etc. were studied experimentally.

The minimum explosive concentration increased exponentially with particle size. The minimum explosive concentrations of the sample dusts were about 170 g/m3 (aluminium: 0–8 μm) and 90 g/m3 (magnesium: 0–20 μm). The minimum ignition energy tended to increase with particle size. It was about 6 mJ for the aluminium samples and 4 mJ for the magnesium samples. The ignition temperature of dust clouds was about 750 °C for aluminium and about 520 °C for magnesium. The lowest concentrations of oxygen to produce a dust explosion were about 10% for aluminium and about 8% for magnesium. A large mixing ratio (more than about 50%) of calcium oxide or calcium carbonate was necessary to decrease the explosibility of magnesium dust. The experimental data obtained in the present investigation will be useful for evaluating the explosibility of aluminium and magnesium dusts generated in metal recycling operations and thus for enhancing the safety of recycling plants.  相似文献   

238.
All economic sectors are associated with energy use; therefore, government organizations aim to supply sustainable energy for human needs and economic growth. In particular, increased environmental concerns of the public in Turkey have impacted policymaking for renewable energy (RE) management in Turkey. The primary objective for RE sources of the Turkish Ministry of Energy is to ensure that 30% of the share of electricity production is from RE resources in 2023. In this paper, the integrated multi-objective, multi-period linear programming model is presented to determine effective allocation of RE supply for seven different geographical regions in Turkey for the period of 2017 to 2024. The integrated model consists of two different stages. The first stage involves qualitative evaluations of RE sources for seven geographical regions. Analytical Hierarchy Process (AHP) is applied to determine criteria priorities and overall ratings of geographical regions across determined criteria for RE sources are computed. The second stage of the integrated model consists of a multi-objective, multi-period linear programming model. The proposed multi-objective linear programming model is coded in MPL (Mathematical Programming Language) and solved using the GUROBI 5.1.0 solver. The output of the integrated model presents the total supply amount of RE sources for geographical regions in planning period. The ε-constraints method is applied to compute the total supply amount of RE from geographical regions for the period of 2017 to 2024. In this study, a systematic decision-making model is generated to allocate renewable energy sources to the geographical regions. The presented model integrates qualitative evaluations and quantitative parameters of different geographical regions to determine the optimal supply amount of RE. The obtained results are consistent with the potential quantities of RE alternatives in geographical regions, regional specifications, and social requirements.  相似文献   
239.
ABSTRACT: The continuous availability of ground water to riparian phreatophytic vegetation results in large evapotranspiration (ET) losses in summer. Chemical or physical eradication of this vegetation can have undesirable environmental side effects. Spraying phreatophyte foliage with a nontoxic antitranspirant (AT) may reduce transpiration without eradication. Transpiration rate per unit leaf area was similar for several phreatophyte species, but ET per unit land area of phreatophytes depneds more on stand density than species. The mean ET for saltcedar in June was 8.1 mm/day measured by Bowen ratio, compared with 7.9 mm by lysimeters. ATs and growth-retardants reduced transpiration by over 50 percent in laboratory tests where foliage was thoroughly sprayed. In the field AT sprayed by a back-pack mistblower reduced ET by 20–35 percent initially and 10 percent after a month. No ET reduction occurred when AT was sprayed by helicopter on saltcedar, because excessive droplet size and heavy salt deposits on the foliage resulted in poor spray adherence. Wax-based AT was relatively nontoxic to fish and wildlife. Dissolved oxygen could be reduced for aquatic life, but further AT dilution in streams and ponds would minimize this. Helicopter spraying may affect bird nests and egg hatchability. Although ATs significantly reduce ET, their high cost and spraying difficulties preclude current use on phreatophytes. With improvement they may economically help to conserve water in riparian areas in future years.  相似文献   
240.
A myriad of factors, both economic and political, influenced the voting by members of the United States Congress on the 1978 National Energy Act. Determinant factors considered in our analysis included the percentage of residents in the Congressman's district residing in the central city or on farms; the percentage of residents who belong to labor unions; the average level of education of the residents; oil, coal, and natural gas production in the state relative to total domestic production. The results, determined by means of logit analysis, indicate that the impact on low-income energy consumers, the effect on overall employment, the impact on farmers, and the benefits to energy interests, as well as ideology and the subjective perception that the need exists to do something about the energy situation in the United States, were all important explanatory factors.The author is an economist with the United States Department of Energy. The views expressed are those of the author and do not necessarily represent the policies of the Department of Energy or the views of other Department of Energy staff members.  相似文献   
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