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391.
392.
Environmental changes associated with mass urban tourism and nature tourism development in Hong Kong 总被引:4,自引:0,他引:4
C. Y. Jim 《The Environmentalist》2000,20(3):233-247
Hong Kong's tourism is overwhelmingly urban-focused. There is a heavy concentration of tourist and ancillary facilities in a small core urban area. A well-defined tourist business district has evolved with imprints on urban morphology. Hotels and the travel industry have limited direct environmental impacts; recent efforts have reduced energy and water consumption and waste generation. Changing preferences and market diversification call for countryside and resort types of tourism. The mainly young visitors are increasingly interested in the scenic countryside with a well-established country-park system, the tourist potential of which has been neglected. Hitherto rural excursions have been confined to 'honeypots' with little penetration away from main roads. The varied possibilities of nature tourism with ecotourism ingredients can be tapped as an adjunct to the city-based counterpart. New tourist nodes such as scattered resorts and a resort island can bring visitors close to nature. The changing patterns of consumption and the increase in rural visitorship demand measures to forestall environmental degradation. 相似文献
393.
Eco-environmental changes and causative analysis in the source regions of the Yangtze and Yellow Rivers, China 总被引:4,自引:0,他引:4
In the most recent four decades the eco-environment in the source regions of the Yangtze and Yellow Rivers has been continuously getting worse, this is mainly manifested in the serious vegetation degradation, rapidly developing desertification, lake shrinkage and salinization, wetland degradation and biodiversity reduction. This paper attempts to give a quantitative analysis to such eco-environmental changes and explore their causes. The main factors responsible for such changes are climate change and the alterations of glacial snow accumulation and the freeze-thaw processes of the frozen soil, as well as overgrazing and rodent damage. The eco-environmental changes in the source regions not only influence the social-economic development of these regions but also have affected, or are affecting, the whole river basins' social-economic development. 相似文献
394.
E. A. Platonova 《Russian Journal of Ecology》2001,32(6):375-381
The distribution of tree species in the landscape was studied using the approach based on the comparison of the ecological requirements of species and the properties of ecotopes distinguished by their position in the relief and peculiarities of basement rocks. The types and specificity of ecological regimes were determined for the typical ecotopes of the southern Karelian ridge landscape. The main environmental and successional factors determining the distribution of seven forest-forming tree species in the ecotopes of this landscape were identified. The results of this work can provide a basis for the prognosis of forest vegetation in the landscape studied. 相似文献
395.
Joan Iverson Nassauer Sandra E. Kosek Robert C. Corry 《Journal of the American Water Resources Association》2001,37(6):1439-1443
ABSTRACT: Appearances matter for managing riparian landscapes because the appearance of landscapes affects public willingness to accept plans and designs that improve ecological quality. Riparian landscape design and planning should respect and strategically incorporate characteristics that the public values and expects to see. Such design can be quite novel in its ecological effects, but it also should be sufficiently familiar in appearance to correspond with cultural values. This paper describes some influential cultural values for riparian landscapes and demonstrates how attention to such values supports public acceptance of ecologically innovative design in rural and urban watersheds. 相似文献
396.
景观资源是为满足人类精神需求的战略性资源.景观资源是旅游业发展的物质基础,它对区域发展战略和城市风貌具有决定性影响.笔者提出了景观美学识别的三项原则,概述景观评价的内容与方法,提出景观资源保护的途径与策略:作好保护规划、立法保护、开展建设项目景观影响评价和树立保护景观资源的正确观念. 相似文献
397.
398.
流域地表生态信息的卫星遥感图像处理技术 总被引:1,自引:1,他引:0
以福建省九龙江流域为例,利用计算机技术和遥感-GIS工具软件,探讨利用多源卫星遥感影像获取流域地表环境信息的图像处理与分析技术,列举卫星遥感可获取的流域地表生态环境专题信息。重点分析利用遥感-GIS界定流域范围的方法、流域地表覆盖状况和植被覆盖密度的卫星遥感影像处理方法。 相似文献
399.
黑龙江省近50年来沼泽湿地退缩特征及其原因分析 总被引:2,自引:0,他引:2
在RS和GIS的支持下,综合集成1954年地形图和2000年TM影像重建黑龙江省1954~2000年沼泽湿地的空间信息矢量数据,结合斑块质心变化模型、景观参数和欧几里德最短距离函数,分析黑龙江省沼泽湿地退缩的区域分异特征,进一步从人类活动对沼泽退缩的影响的角度探讨沼泽退缩的原因。研究结果表明:黑龙江省近50年来,沼泽湿地面积急剧减少,由791.4×104hm2减少到303.5×104hm2;沼泽景观趋于破碎化;退缩的焦点区域主要集中在三江平原、大小兴安岭和松嫩平原。导致湿地退缩的人文原因主要包括三个方面:人口增加和耕地的不断开垦,国家建设国营农场的农业发展政策,与主要公路的空间区位关系。 相似文献
400.
基于GIS的城市最小生态用地空间分析模型研究——以深圳市为例 总被引:13,自引:3,他引:10
21世纪,全球范围内城市化已经成为人类社会发展的必然趋势,城市扩张不可避免地将大量的森林、农田、草地、湿地和水域等发挥着重要生态服务功能的生态用地转化为城市建设用地,对城市、区域乃至全球的生态系统造成较大的影响。在未来快速城市化过程中,保护必需的生态用地对于维持城市自身生态系统健康、改善城市居民生活质量和城市可持续发展有着重要意义。研究以中国经济特区深圳市为例,将景观生态概念模型与生态系统服务功能价值评估方法结合起来,在GIS技术的支持下,构建了城市最小生态用地空间分析模型,并分别按照保留城市面积30%、40%、50%和60%生态用地的4种情景,分析最小生态用地空间分布的合理性,结果表明论文所构建的最小生态用地模型能够很好地将城市当中具有重要生态系统服务功能的土地提取出来。 相似文献