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351.
上海潜在滨海旅游资源调查及开发研究 总被引:1,自引:0,他引:1
上海市的海岸线蜿蜒460km,涉及5区1县,潜在滨海旅游资源亟待开发。为了更好地了解和掌握潜在上海滨海旅游资源的现状,结合上海独特的自然禀赋和社会经济条件,参照《旅游资源分类、调查与评价(国家标准)》(GB/T18972-2003),在对上海潜在滨海旅游资源普查的基础上,研究了上海潜在滨海旅游资源分类,分析了潜在滨海旅游资源特征和资源富集区状况,选划出上海应重点开发的6大潜在滨海旅游资源区,并分别就各资源区的开发对策与建议提出初步构想。 相似文献
352.
Jean-Christophe Gaillard Catherine C. Liamzon Jessica D. Villanueva 《Environmental Hazards》2007,7(4):257-270
Between 14 November and 4 December 2004, four successive tropical depressions and typhoons lashed the Eastern coast of Luzon in the Philippines. Heavy rainfall triggered massive landslides and devastating flash floods, which brought tremendous damage and killed more than 1600 people. Immediately after the disaster, there was a media and political consensus to incrimate ‘extraordinary’ natural phenomena and widespread deforestation as responsible for the catastrophe. We argue that the tragedy that befell the municipalities of General Nakar, Infanta and Real, among other devastated areas, is enmeshed in a deeper tangle of causal factors that are political, socio-economic and demographic in nature. These factors include unmanaged population growth, difficult access to land and resources, corruption within the government, and power of the elite. 相似文献
353.
我国生态安全现状分析及保护对策研究 总被引:3,自引:3,他引:3
生态安全是国家安全的重要组成部分,是国防安全、政治和经济安全的基础。笔者论述生态安全的基本含义、构成和特点,分析我国生态安全在国土资源安全、水资源安全、环境安全和生物物种安全等方面存在严重的问题,指出我国生态安全有加速恶化的趋势。以其为基础,提出了保护我国生态安全的具体对策和措施,为我国生态安全提供切实可行的手段和途径,旨在提醒国人对生态安全引起高度重视,有效保护我国的生态安全。 相似文献
354.
清代在水土资源、林木资源、矿产资源的保护与利用等方面采取了积极有效的措施,包括开垦土地、兴修水利、发展生态农业、植树造林、加强法制、设立环保机构等。 相似文献
355.
356.
Nora M. Znotinas Keith William Hipel 《Journal of the American Water Resources Association》1979,15(1):44-59
ABSTRACT: Procedures are presented for comparing and evaluating alternative engineering designs for a particular water resources project. By using certain aspects of fuzzy set theory, it is possible to introduce both quantitative and qualitative considerations into the decisionmaking process. In addition, the viewpoints of the various interest groups involved with the water resources development can be realistically incorporated by the evaluation techniques for the alternative designs. Methods are given for eliminating undesirable alternatives and thereby obtaining a reduced set of possible feasible solutions to the problem. Because of the flexibility of the evaluation methods, the viable alternatives should not only satisfy economical, technical. environmental and other types of constraints, but these possible solutions should be politically feasible as well. A method is formulated for checking the sensitivity of the feasible results with respect to the factors that are considered in the analysis. 相似文献
357.
358.
Gary L. Larson 《Environmental management》1980,4(2):105-110
Since the presentation of the Leopold Report (Leopold et al. 1963) to the United States Secretary of the Interior, recommendations in the document for managing natural park resources on the ecosystem level have been included in the management policies of the National Park Service. In many instances, however, management programs have continued to focus on individual resource problems, without apparent concern for the ecological consequences on ecosystems. Without knowledge of the interrelationships of ecosystem components, solving one problem may result in other resource problems. Graphic approaches are presented as potential tools to view these complex interrelationships relative to the needs of the resource manager. Interpreting the dynamics of aquatic systems is emphasized. 相似文献
359.
David M. Meko Charles W. Stockton William R. Boggess 《Journal of the American Water Resources Association》1980,16(4):594-600
ABSTRACT: Indices of annual diameter growth of trees were used to reconstruct drought in southern California back to A.D. 1700. A regional Palmer Drought Index served as predictand and tree-ring indices from eight sites as predictors in multiple linear regression analyses that yielded the prediction (reconstruction) equations. The regression explained 69 percent of the variance in Palmer Index in the period of calibration. The long-term reconstruction indicated that drought was rare in the first half of the current century relative to other discrete 50-year periods, and that based on evidence to date the last half of the 20th century may well turn out to be the most drought prone since A.D. 1700 in southern California. 相似文献
360.
Roger D. Hansen Michael F. Torpy Michael Kemp David Mills 《Journal of the American Water Resources Association》1980,16(5):862-865
ABSTRACT: The authors conducted a mail survey of 600 employers in the government and private sectors who were thought to hire water track environmental engineers. Of a total of 148 respondents, over 80 percent employed a combined total of over 2,800 environmental engineers. The survey addressed two basic questions: (1) what is the quality of graduate education recently trained engineers have received, and (2) what effect does a nonengineering undergraduate degree have on an engineering graduate student's employment potential. In answer to the first question, respondents indicated that engineering graduates were deficient in report writing, business law (contracts and specifications), economics and finance, and practical design. Many employers stated that students could better prepare themselves for employment by (1) obtaining professional experience through internships and summer or part-time jobs, and (2) learning to communicate effectively, both orally and in writing. In answer to the second question, 50 percent of the respondents indicated that engineers without an engineering undergraduate degree would not necessarily be limited in their abilities to perform engineering duties. 相似文献