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Daşdemir I 《Environmental management》2005,35(3):247-257
The purpose this study was to improve operational planning and management of national parks in Turkey to balance conservation use and sustainable management. Souksu National Park (SNP) was chosen as the study area. The data were obtained from interviews of 182 visitor groups (in total, 819 people) and analyzed using correlation, factor, discriminant, and regression analyses. It was found that the most important factors affecting operational planning and management of SNP are (1) travel cost, (2) visitor welfare level, (3) intensity of use, (4) size of visitor group, (5) type of recreational demand. The main source of visitors to SNP is from a zone within a 0–90-km radius. This region comprised 53.85% of total visitors to the park. The capital of Turkey (Ankara) is the most important source of visitors from within this zone. The optimum activity mix in SNP is also determined. Picnicking, viewing the scenery, and nature walks or trekking comprised the main uses of the park. It is anticipated that these findings will help to improve operational planning and sustainable management of the national park and the environment. 相似文献
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Rosamund McDougall 《The Environmentalist》2008,28(2):155-157
Europe’s growing energy deficit and destabilising climate may lead the EU and its constituent member states to change its
attitude to population size and growth. 相似文献
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干旱地区水污染控制系统初探 总被引:2,自引:0,他引:2
应用数学规划方法,科学地组织污染物的排放或科学地协调各个治理环节,以乌鲁木齐市水磨河流域水污染控制系统为例,对干旱地区水污染控制系统进行了初步探索,从而得出干旱地区污水处理费用的合理负担,并得出污染物排放的数量,质量受自然地理条件制约的结论。 相似文献
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In this study, a model to estimate the optimum mine size is developed. The model is developed on the basis of marginal analysis. The model solves for the production rate at which the present value of marginal costs equals the present value of marginal revenues—the rate that microeconomic theory shows will maximize the net present value of production from the mine.In addition, the article discusses the effects on the optimum production rate of: the physical characteristics of the deposit, economic factors, and financial factors. It has been found that, not surprisingly, as the reserve tonnage increases, the optimum mine size increases. Also, the optimum production rate increases as the ore grade increases. A direct relationship has been found between the mineral price and the optimum production rate. The optimum mine size is found to be inversely related to the expected growth rate of mineral price, while it is directly related to the expected growth rate of mining costs. A concave relationship has been found between the cost of capital and the optimum mine size. 相似文献
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医院污水处理的消毒剂及消毒工艺 总被引:3,自引:0,他引:3
综合比较目前国内常用的医院污水消毒处理方法,介绍消毒剂的种类和有效氯含量,论述各种消毒工艺的优缺点。 相似文献
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In the investigation of soil cover design options for final decommissioning of reactive mine waste, it is often necessary to analyze or predict the anticipated cover performance as a function of the cost of implementation, which is governed by the type, number and thickness of the layers in the cover system. An example of such investigation is presented in this study where one-dimensional evaporation from hypothetical moisture-retaining cover systems is simulated to assess the influence of several cover properties and hydrogeologic parameters on performance. The commercially available transient flow model, SoilCover, was used to compute suction and water content profiles for different cover design scenarios. The predicted water content profile and porosity of layers were then used to estimate the oxygen diffusion coefficients of the various layers. The oxygen diffusion coefficients were used to estimate oxygen flux through the cover systems. The oxygen flux was, in turn, related to the maximum acid flux. The studied cover and hydrogeologic parameters included soil type, thickness of barriers, and water table elevation. Two types of infiltration and oxygen barrier and two types of capillary layer with different thicknesses were studied. The water table was either kept constant at the base of the waste (tailings) or dropped by 0.5, 1, 2, and 3m over 120 days. The results showed that the relationship between water table depression and the thickness of capillary layers, on one hand, and desaturation of the infiltration and oxygen barrier, on the other, is not linear. Relationships between oxygen flux and barrier thickness and between cost increase and performance improvement of the studied cover systems are presented. Finally, a method that outlines steps for site-specific and economically feasible design of multi-layer cover systems is introduced. 相似文献
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本文阐述了我国的污水处理方式现状,认为发展分散式废水处理系统,坚持分散处理和集中处理相结合,中心城区以集中处理外排为主、郊区以分散处理为主的方式,将是提高我国污水处理率的发展趋势。 相似文献