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101.
简要地介绍了开展大城市地震活断层探测的意义及世界各国开展活断层探测的基本情况。城市及邻近地区地震活断层引起的直下型地震 ,将会给大城市造成巨大的地震灾害。准确地探测出大城市的活断层分布 ,采取有效措施 ,可大大降低地震时的损失。文中重点介绍了开展地震活断层探测的地球物理方法的类型和主要特点 ,在区域探查与初步鉴定阶段、详细探测与精确定位阶段、孕震构造探测阶段可能涉及到的各种地球物理探测方法、适用范围及所能解决的主要问题 相似文献
102.
该系统提供了航空红外遥感资料的袢时采集和传输,为及时开展地震野外调查工作提供了一个有力的手段。该系统由红外传感器系统、机载站图像和数据实时处理系统、机载站通信系统、转发站通信系统、地面站接收系统、地面站图像和数据实时处理系统组成。 相似文献
103.
Mordechai Haklay 《Area》2002,34(1):17-28
Public access to environmental information received much attention in the last decade. Recent developments promote access to this information through public telecommunication networks. This paper describes a Web-based survey that explored the requirements and needs of likely users of public environmental information systems for London: educated middle-class members of the public, with high interest in environmental issues and computer literacy. The survey demonstrated current information consumption patterns and the reasons to gather and use such information. 相似文献
104.
Robert Gilbert 《Journal of Paleolimnology》2003,29(2):209-220
A sub-bottom acoustic survey of Devil Lake on the Canadian Shield in southern Ontario reveals three acoustic facies: (I) a moderately acoustically transparent, laminated sequence interpreted as a glacilacustrine deposit in glacial Lake Iroquois or a subsequent phase in water depths up to 200 m greater than at present, (II) a transitional more transparent, less layered facies interpreted as being deposited in a more distal glacial lake from erosion of sediment in the watershed exposed by the failure of the ice dam and lowering of the glacial lake before stabilization by the development of forests, and (III) an acoustically transparent facies with similar transmissivity to the water column, interpreted as Holocene gyttja. Each is spatially variable in extent and thickness in response to those processes. There is only a very weak relation between sediment thickness and the water depth in which it was deposited. Wave processes prevent deposition in water depths less than about 6 m and evidence of erosion to the greatest depths of the lake (>40 m) is pervasive. The data demonstrate the value of acoustic survey in assessing lacustrine processes and the history of lakes, and the significance of such documentation in planning a coring program and in interpreting the results. 相似文献
105.
Commercial alpine medicinal plants are collected from the wild by local rural households throughout the Himalaya and sold in order to increase household incomes. Recent studies indicate that this annual trade amounts to thousands of tonnes of roots, rhizomes, tubers, leaves, etc., worth millions of US dollars. The main market is in India. Based on a national survey, including the most commonly traded species, and a village study this paper investigates the importance of the alpine medicinal plant trade at national and local levels in Nepal. The national survey included standardized open-ended interviews with 232 harvesters, 64 local traders, 66 central wholesalers, 47 regional wholesalers, and 16 production companies. The village survey is based on the daily records of household activities in 15 households in a one-year period. The annual Nepalese alpine and sub-alpine medicinal plant trade is conservatively estimated to vary from 480 to 2500 t with a total harvester value of US$0.8–3.3 million; the average harvester value is estimated at US$66.0 ± 99.0. The trade in 1997/98 amounted to 1600 t with a harvester value of US$2.3 million and an export value equivalent to 2.5% of total export from Nepal. Medicinal plant harvesting was found to constitute an integrated part of local livelihood strategies, contributing from 3 to 44% (average of 12%) of the annual household income. Importance at household level depended on land and animal holdings, and the availability of adult male labour. The validity and reliability of methods and analyses is evaluated, and issues of conservation and management of alpine medicinal plant species under the community forestry scheme are discussed. 相似文献
106.
107.
试论少数民族地区的生态化旅游开发 总被引:6,自引:7,他引:6
生态化旅游开发是有别于传统的旅游开发的一种可持续开发与发展的理念,它追求的是生态、社会和经济综合效益的最大化,应该成为旅游开发与旅游业发展的主要方向。民族地区的旅游开发具有特定的区域生态特征。其生态化旅游开发的核心问题是旅游环境容量的确定与旅游环境的保护、民族特色与民族文化的弘扬以及注重旅游经济发展过程中旅游业的拉动效应及其依托性之间的关系处理等。 相似文献
108.
Habitat, occurrence and conservation of Saharo-Arabian-Turanian element Forsskaolea tenacissima L. in the Iberian Peninsula 总被引:1,自引:0,他引:1
Javier Cabello Domingo Alcaraz Francisco Gmez-Mercado Juan F. Mota Javier Navarro Julio Peas Esther Gimnez 《Journal of Arid Environments》2003,53(4):491-500
The aim of this study is to assess the Iberian populations of Forsskaolea tenacissima L. according to its biogeographical interest, habitat, geographical range and conservation status. Results point out that they are restricted to gravel wadis of Tabernas Desert (SE Spain), are scarcely included in protected areas and represent historically isolated populations with relict behaviour. We also describe a new association, Senecioni-Forsskaoleetum tenacissimae. Conservation status of species is cause for concern and two conservation actions must be carried out. Firstly, protected areas should house Forsskaolea populations and secondly, phytosociological characterization of a community allows inventorying its habitat and directing conservation efforts to community level. 相似文献
109.
覆盖区地球化学异常是由自然和人为因素引起的,在土壤垂直剖面上元素有多种分布类型,它反映了元素在土壤中迁移、演化及人为干扰的分布特征;通过对自然和人为污染的地球化学异常源追踪和评价,为环境污染治理和地区经济可持续发展提供决策依据。 相似文献
110.
介绍了桃园煤矿井下所见陷落柱的出露特征。为指导巷道施工,消除水患威胁,采取了综合勘探方法查明陷落柱的范围、高度、导水性等情况,并阐述了注浆加固综合治理陷落柱的方法。 相似文献