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191.
In order to find out the factors which influence community participation in tourism,several effect factors are summed up through the investigation of the local residents and the analysis of the logistic regression of the data gained from Xingwen world Geopark.Results indicated there are several main influencing factors of community participation such as the comparative benefit of tourist industry,participant residents’ subjective wishes,preference consciousness of working opportunity obtainment in the tourist enterprise and participant skills.Based on above investigation data and field travel,the paper put forward several methods about how to enhance the residents’ participant degree:increasing the comparative benefit of tourist industry,enhancing the attraction of tourism for boosting participant wishes,improving the preference consciousness on obtaining working opportunity in tourism industry and cultivating residents’ participant skills through training.  相似文献   
192.
三峡库区巴东新城区库岸三叠系巴东组层间软弱带   总被引:3,自引:1,他引:2  
摘要 巴东新城区发育有黄土坡滑坡、赵树岭滑坡、太矶头滑坡、童家坪滑坡等多处大型古滑坡,研究库岸斜坡岩体结构特征对滑坡的治理有着至关重要的作用。本文基于巴东新城区白土坡和西壤坡两段库岸深300余米监测剖面的地质勘探资料,根据岩芯颜色、岩性和结构将巴东组第三段划分为24段;通过薄片鉴定、X射线衍射和岩芯精细测量分析库岸斜坡岩体处于滨海环境的海陆过渡相,岩性组合、岩层厚度、矿物组成及强度具有复杂的垂向分带特征;探讨了层间软弱带和大型滑坡的关系。研究表明:巴东新城区库岸斜坡巴东组第三段内发育有13层贯通的软弱带,表现为为富含泥质、结构破碎的泥质软弱夹层、构造碎裂岩、溶蚀改造带和软岩软弱带。在沉积成岩时经历了滨海相反复的海浸海退,软弱带多分布在沉积环境动荡的开阔台地(陆棚泻湖)和局限台地(潮间带)。巴东组第二、三段岩性及沉积环境属缓慢过渡,在构造作用下未发生明显的滑脱。沉积结构和后期构造共同作用形成了贯通软弱带,为大型滑坡发生提供了有利条件。三峡水库全面蓄水后,软弱带在地下水长期作用下必将加剧库岸斜坡的深部形变。  相似文献   
193.
The rifted Eastern Continental Margin of India (ECMI) has evolved as a result of breakup of East Gondwanaland. Previous geophysical studies of the continental margin have not elucidated upon its volcanic nature. Magnetics plays a useful role in the study of continental margins, particularly in identifying the volcanic units. The aeromagnetic map of the offshore Mahanadi basin of ECMI displays a conspicuous linear anomaly along the continental shelf. A comprehensive study of the published aeromagnetic, marine magnetic and gravity data of the offshore Mahanadi basin reveals the existence of a seaward dipping volcanic unit in the offshore Mahanadi basin bordering the Hinge zone. This inference suggests that the ECMI is a volcanic rifted margin. The study further indicates the deepening of the basement towards the sea. In addition, the existing geological studies on the ECMI demarcated the probable limit of the continental crust by studying the basement detached tectonic style of the sedimentation in sub-surface configuration of the East coast basins of India. The probable continental crustal limit, the Hinge zone, and the inner edge of the presently inferred volcanic unit conform to one another spatially in the offshore Mahanadi region. These features characterize the inferred volcanic body as seaward dipping reflectors (SDRs) that usually occur at the rifted continental margins. The deepening of the basement towards the sea and the presence of the volcanic body on the continental margin are indicative of the transitional nature of the crust. It is generally accepted that Antarctica and India were juxtaposed before the breakup of Gondwanaland. But the microcontinents in the southern Indian Ocean are neglected in the reconstruction of Gondwanaland continents. The recent studies of the discovery of continental crust within the Elan Bank (EB) microcontinent show that the EB was contiguous with the East coast of India before the breakup of Gondwanaland. Moreover, it is reported that the upper igneous crust of the EB consists of a 2–3 km thick layer of accumulated lava flows originating from the Kerguelen hotspot. An estimate shows that the total volume of volcanic and plutonic component of the Elan Bank is about 0.3 million cubic kilometers. The present inference of a volcanic body from the offshore Mahanadi basin is in agreement with the above observations of the juxtaposition of EB with ECMI.  相似文献   
194.
倪兆球 《热带地理》1999,19(3):268-274
探讨了世纪之交世界社会经济发展与生态环境之间存在的矛盾, 提出了根据各国经济发展水平、国土面积、人口和对资源环境的开发利用与保护的差别, 把世界分为富国资源高消费型、新兴工业国资源大量需求型、穷国生态破坏型、石油输出国环境脆弱型, 以及各类国家的可持续发展型式。还提出要实现全球可持续发展战略, 必须采取的共同对策  相似文献   
195.
设计和编制海陆统筹的综合航海地图集服务于国家“构建海洋命运共同体”发展目标,同时也是促进海陆文化共融和海陆睦邻合作的重要推力,在当前地图学领域受到普遍关注。本文通过与航海专题图、陆地专题图的对比分析,从地图选题、比例尺、投影、地理分幅等方面探讨了海陆统筹地图集的表达特点,并从海陆并蓄视角出发,提出综合航海地图集基础地理框架的内容体系和构建策略。在此基础上,结合《世界航海地图集》的编制实践设计了其基础地理框架的具体建立方案:(1)中小比例尺地图使用WGS84坐标系,较大比例尺地图使用CGCS2000坐标系;(2)根据专题内容、制图区域、变形需要,制图单元可以使用等差分纬线多圆锥、墨卡托、古德等多种投影;(3)地理底图分为世界地图、典型区域地图、陆地地图、海域地图、航区地图、港口地图6种图型,其系列比例尺内容需按一定规则进行取舍和化简派生得到;(4)地图制图单元采用北方定向,联合地理分幅和地图分幅可生成灵活的图面布局。世界航海专题图集的编制实践表明,应用本文建立的基础地理框架能较好实现海洋与陆地的协调统一表达。  相似文献   
196.
三峡工程运用后长江中游荆江河段河床持续冲刷,局部河段崩岸频发,影响河道内悬沙输移与河床形态调整.本研究采用实测长程河道地形及固定断面地形资料,确定了2002-2018年荆江河段的主要崩岸区域,估算了崩岸土体的泥沙总量,进而定量分析了河岸崩退对河床调整的影响.计算结果表明:荆江段累计河岸崩退体积约为2.0亿m3,约占该河...  相似文献   
197.
穿越南沙礼乐滩的海底地震仪广角地震试验   总被引:7,自引:9,他引:7       下载免费PDF全文
本文对穿越礼乐滩东北部向西北方向延伸进入中央海盆长369 km的广角地震剖面OBS973-2进行了反演研究,以期了解南海南部陆缘的地壳结构,同时探讨南、北陆缘的共轭问题.结果表明OBS973-2剖面的速度模型中三个沉积层的速度分别为1.8~2.0 km/s、2.0~2.7 km/s和3.5~4.0 km/s;沿剖面沉积...  相似文献   
198.
2015 is the International Year of Soil (IYS) adopted by the 378th Congress of the United Nations. The Status of the World’s Soil Resources was released by the Food and Agriculture Organization of the United Nations, which was the policy report about the status of the world soil resources for the first time. The universal values of the global community were strengthened by the challenges for the global society from the risk and safety of the change of soil quality, functions, services and soil health. One third of the world soil resources were suffering serious degradation, which could affect the food security in the future, regional development and local conflicts in the report. The major task of the global monitoring, regulation and management of the world soil resources and the social responsibility of supporting the sustainable soil management by education, research and technology development were highlighted. The social responsibility and global development trends of soil science and management strategies were discussed by the keywords, the distribution of contributing authors and the citation of the references, as well as the main contents of the report. The keywords distribution of the report showed that the focus of the soil research included the change of soil quality, processes, functions and services induced by the natural driving forces, human’s activity and soil degradation, as well as the hotspots covered soil carbon/nitrogen-water-biological pool and distribution related with the biogeochemistry, global climate change and ecosystem functions and human health. The number and structure of the cited papers showed that the integration research based on the mega-data analysis were the prominent development trend of the soil science. The geographic distribution of all the contributing authors showed that dominant discourse of the global soil science were grasped by the developed countries including Europe and the United States, China had just limited effects on the global soil science. It is urgent to promote China’s soil science research and the services for global society.  相似文献   
199.
Implementing conservation actions on-the-ground is not a straightforward process,especially when faced with high scientific uncertainty due to limited available information. This is especially acute in regions of the world that harbor many unique species that have not been well studied,such as the alpine zone of the Hengduan Mountains of Northwest Yunnan (NWY),a global biodiversity hotspot and site of The Nature Conservancy’s Yunnan Great Rivers Project. We conducted a quantitative,but rapid regional-level assessment of the alpine flora across NWY to provide a broad-based understanding of local and regional patterns of the alpine flora,the first large-scale analysis of alpine biodiversity patterns in this region. Multivariate analyses were used to classify the major plant community types and link community patterns to habitat variables. Our analysis indicated that most species had small distributions and/or small population sizes. Strong patterns emerged with higher diversity in the more northern mountains,but beta diversity was high,averaging only 10% among sites. The ordinations indicated that elevation and geographic location were the dominant environ-mental gradients underlying the differences in the species composition among communities. The high beta diversity across the alpine of these mountains implies that conservation strategies ultimately will require the protection of large numbers of species over a large geographical area. However,prioritiza-tion should be given to areas where potential payoffs are greatest. Sites with high species richness also have a greater number of endemic species,and,by focusing efforts on these sites,conservation investments would be maximized by protecting the greatest number of unique species.  相似文献   
200.
In this study,we used remotely sensed data,GIS modeling,and statistical methods to evaluate the damage caused by the Wenchuan Earthquake (May 12,2008) to the giant panda (Ailuropoda melanoleuca) habitat in the World Nature Heritage Sichuan Giant Panda Sanctuary (WHSGPS) in China.A landscape ecological analysis found increases of landscape heterogeneity,complexity,and fragmentation in the giant panda habitat after the earthquake.A terrain analysis found that slope and elevation are directly associated with t...  相似文献   
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