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991.
上海市旅游生态足迹分析 总被引:1,自引:0,他引:1
运用生态足迹的理论与方法,结合旅游者的生态消费及结构特征,借助现代地理信息技术,对上海市旅游生态足迹进行了分析。通过测算,2009年上海市旅游生态足迹为66 333 483.428hm2,人均旅游生态足迹为466.547×10-4 hm2;旅游生态承载力为1 900 029.08hm2,人均旅游生态承载力为146.908×10-4 hm2,人均生态赤字为319.692×10-4 hm2。从上海市旅游生态足迹结构来看,旅游交通和旅游购物足迹的比例最大,分别占71.79%和23.76%,旅游餐饮和休闲娱乐其次,分别为3.44%和0.14%,比例最小的是旅游观光和旅游住宿。这表明旅游活动正在过度消耗上海城市资源环境,旅游业目前处于生态赤字状态,因此应采取相关的改进措施,以实现资源保护与旅游发展的平衡,并着手调整旅游产业内部结构,发展环保节能的交通工具,大力推动低碳旅游发展,开发有特色的旅游商品,提高旅游购物消费,在保证生态资源可持续利用的同时保持旅游经济快速发展。 相似文献
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Alessandro Paletto Federica Maino Isabella De Meo Fabrizio Ferretti 《Environmental management》2013,51(2):414-422
Values are generally defined as social facts that orientate individual and collective actions, and consequently influence political, economic and social systems. The evaluation of natural resource values is considered an important instrument to support decision making in environmental policy. The forest is an important renewable resource that provides a mix of social, economic and environmental values for society. The paper presents a survey method to collect and analyse individual preferences relating to three macro-categories of forest values. The survey method was tested in the Trentino region (north-east of the Italian Alps) and will soon be extended to other areas. The results of the questionnaires provided evidence that the forest economic value is perceived as least important, while the environmental values were appreciated the most. Regarding the principle social variables, males tended to give higher scores to all three macro-categories compared to females. Moreover, people with a low education also gave higher scores to all three categories in comparison to the more educated individuals. 相似文献
993.
采用加速溶剂萃取处理土壤样品,用超高效液相色谱串联质谱法测定样品中15种氨基甲酸酯类农药残留,方法在5.00μg/L~200μg/L范围内线性良好,检出限为0.3μg/kg~0.5μg/kg,加标回收率为78.9% ~116%,6次测定结果的RSD为0.7% ~15.7%.试验表明:不同地域的6种标准土壤对15种目标物... 相似文献
994.
The discharge of brackish water, as a dense jet in a natural water body, by the osmotic power plants, undergoes complex mixing processes and has significant environmental impacts. This paper focuses on the mixing processes that develop when a dense round jet outfall perpendicularly enters a shallow flowing current. Extensive experimental measurements of both the salinity and the velocity flow fields were conducted to investigate the hydrodynamic jet behavior within the ambient current. Experiments were carried out in a closed circuit flume at the Coastal Engineering Laboratory (LIC) of the Technical University of Bari (Italy). The salinity concentration and velocity fields were analyzed, providing a more thorough knowledge about the main features of the jet behavior within the ambient flow, such as the jet penetration, spreading, dilution, terminal rise height and its impact point with the flume lower boundary. In this study, special attention is given to understand and confirm the conjecture, not yet experimentally demonstrated, of the development and orientation of the jet vortex structures. Results show that the dense jet is almost characterized by two distinct phases: a rapid ascent phase and a gradually descent phase. The measured flow velocity fields definitely confirm the formation of the counter-rotating vortices pair, within the jet cross-section, during both the ascent and descent phases. Nevertheless, the experimental results show that the counter-rotating vortices pair of both phases (ascent and descent) are of opposite rotational direction. 相似文献
995.
A kinetic model is developed for the oxidation of phenolic compounds by Fenton's reagent. In the first stage a rigorous kinetic model is applied to calculate the different kinetic rate constants for the oxidation process of p-hydroxybenzoic acid. In a second phase a competitive method is applied to calculate these kinetic constants for another 10 phenolic compounds present in agroindustrial and pulp paper wastewaters. These 10 phenolic compounds were: beta-resorcylic acid, 3-(4-hydroxyphenyl)-propionic acid, ferulic acid, protocatechuic acid, caffeic acid, p-coumaric acid, vanillic acid, syringic acid, veratric acid and 3,4,5-trimethoxybenzoic acid. 相似文献
996.
The "Atlas of caesium deposition on Europe after the Chernobyl accident" was prepared within the framework of the Joint Study Project 6 (JSP6) of the collaborative programme on the consequences of the Chernobyl accident between the European Commission and the Ministries responsible for Chernobyl affairs in Belarus, Russia and Ukraine. The radiological data provided by scientific institutes and competent authorities of more than 30 European countries were integrated into an information platform. Data validation and intercomparison were therefore essential before the interpretation of the deposition with the help of isoline maps prepared with a geographic information system (GIS) could be done. The data validation was a two-step procedure: after performing a primary logical consistency check, other techniques based on spatial statistics were used to outline uncertain data. The purpose of this paper is to present these validation methods and to discuss the advantages and constraints of these techniques. Rather than trying to improve the techniques of spatial data analysis, suggestions are made on how an adaptation of the sampling information could improve the final result. 相似文献
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Macroinvertebrate response to acid mine drainage: community metrics and on-line behavioural toxicity bioassay 总被引:1,自引:0,他引:1
Gerhardt A Janssens De Bisthoven L Soares AM 《Environmental pollution (Barking, Essex : 1987)》2004,130(2):263-274
The hypothesis is tested that toxicity of acid mine drainage can be detected by a selection of existing macroinvertebrate community and bioindicator metrices supplemented by toxicity tests with the local mosquitofish Gambusia holbrooki Girard and the shrimp Atyaephyra desmaresti Millet. The behavioural responses of A. desmaresti to acid mine drainage were recorded in the Multispecies Freshwater Biomonitor, based on behaviour and survival as parameters. Bioassessment methods were based on community diversity, structure, function, and bioindicators and supplemented by chemical analysis (temperature, pH, metals). The Biological Monitoring Working Party adapted for the Iberian Peninsula, the number of predators (Coleoptera, Hemiptera) and the number of Ephemeroptera and Trichoptera taxa differentiated the sites well. The on-line toxicity test revealed pH-dependent acute toxicity of the acid mine drainage for the shrimp (LC(50)-48 h: pH-AMD=5.8) and a pH- dependent decrease in locomotory activity with the lowest-observed-response-times (LORTs) within 5 h of exposure. Shrimp were more sensitive to acid mine drainage than fish (LC(50)-48 h: pH-AMD=4.9). A new multimetric index combining toxicity testing and bioassessment methods is proposed. 相似文献