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121.
笔者通过改进先前提出的基于专家证据权重法的成矿远景区划与评价方法的不足之处,重新对青海东昆仑地区Au、Cu和Co3矿种进行成矿远景区划与评价,将各矿种的远景区按成矿潜力大小划分为A、B、C三级。在此基础上,提出了将多个单矿种远景区合成综合成矿远景区的评价方法和手段,最终圈定出青海东昆仑的综合远景区25个,并对它们也按成矿潜力大小划分为A、B、C三级。从青海东昆仑地区已知Au、Cu、Co矿床(点)在各综合远景区内的数量和规模分布情况来看,结果令人满意。青海东昆仑地区的综合选区研究成果可望为该区进一步找矿工作部署提供部分科学依据。  相似文献   
122.
国家于1996年确定了全国35个贫困山区综合开发试点县,并建立了山区综合开发试点贷款这一新信贷种类.通过分析该工作在试点阶段遇到的一些问题和管理难点,提出了改进管理工作的指导思想和对策措施  相似文献   
123.
中国东北及邻区若干地质构造问题的新认识   总被引:99,自引:1,他引:98  
李锦轶 《地质论评》1998,44(4):339-347
本文简要叙述了笔者对中国东北及邻区地质构造的新认识,首次提出了该区株罗纪晚期可能发育与现今青藏高原 类似的古高原的初步见解,对前人“古亚洲洋构造体制”和“演太平洋构造体制”等概念进行了讨论,对中朝地块与西伯利亚地台中元古代以来的构造活动性作了简要的比较。  相似文献   
124.
Through analysis we found that some mesoscale anomalous regions (101–102 km) of meteorological parameters such as the special drought areas, unusual warm areas, the largest snowfall center, low pressure area together with the epicenter area of M S=6.2 Zhangbei earthquake on January 10, 1998 are located at the same area, i.e. there appears the “Five areas corresponding” phenomenon. Meanwhile, three times of low pressure evolution are generated and develop in the earthquake area in five days after the occurrence of the earthquake. The abnormal variation of the lower limit of frozen soil layer shows indirectly that unusual warm in earthquake areas are related to the upward thermal conduction from the deeper layer of earth surface.  相似文献   
125.
长江中下游及邻区基底和花岗岩成矿元素丰度背景的研究   总被引:7,自引:0,他引:7  
马振东  张本仁 《地质学报》1998,72(3):267-275
本文系统地研究了长江中下游及邻区的结晶基底,褶皱基底及花岗岩岩基成矿元素丰度背景,从而为区域Cu、Au,W、Sn等成矿作用提供了一套完整的基础地球化学数据,用此来作为窥视地壳组成及成矿作用时空演变的窗口。  相似文献   
126.
Spatial dynamics of retail structure and the venerable retail hierarchy   总被引:1,自引:0,他引:1  
The retail system is continuously adapting itself to changing demographic conditions, consumer behavior and economic conditions. Existing retail units, getting larger in order to achieve economics of scale, and new forms of large-scale retailing do not fit easily in the traditional spatial pattern of retail concentrations. Neverteless the spatial distribution of retailing in urban areas, as schematized by Berry thirty-five years ago, still has its value. Through an upward hierarchical movement the retail system has adapted itself to an inflexible spatial system, in which downtown has still a dominant position. Future developments, however, may weaken the position of central shopping areas in favour of peripheral locations. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
127.
Tourism and recreation are important economic activities which are major agents of change globally and, more specifically, in wetland areas. There is a regular round of activities associated with the seasons and anything which influences operating seasons is likely to have substantial consequences for tourism businesses Atmospheric conditions influence both whether or not people will participate as well as the quality of the experience. In marine coasts, wetland recreations may be threatened by rising sea levels but recreation in inland water bodies may be affected more by deficiencies rather than superabundance of water. Marinas and recreational boating are harmed by extremes of both high and low water, particularly the latter which is the most likely situation under global climate change. Two main groups can be considered with respect to the potential to adapt to climate change. These are the participants themselves and the businesses which cater to them. It is argued that the former are likely to be much more adaptable than the latter.  相似文献   
128.
论民间法对中国少数民族地区环境法制建设的贡献   总被引:1,自引:0,他引:1  
创始于西方国家的环境法以工业化和民主政治为基础,在工业化程度不高、民主意识欠缺的少数民族地区开展环境法制建设必须尊重当地少数民族的自治权利及社会的法文化传统,发挥民间法对环境法制建设的贡献.因为民间法作为历史文化遗留有巨大的惯性力量,是实际存在于中国现代社会的有效秩序和规范来源.少数民族地区广泛存在的与环境保护相关的民间法能够成为地方环境立法的来源,帮助人们认同国家环境立法,并且弥补国家环境立法的空白,全面细致地规范人们开发利用环境的行为.  相似文献   
129.
While there is considerable international research focused on the conservation outcomes of marine protected areas (MPAs) and marine reserves (MRs) there is little information on the economic cost to establish and manage these protected areas. This study estimated the MR pre-establishment and establishment costs for the Taputeranga Marine Reserve (TMR) in New Zealand (NZ) and determined the annual management costs for this reserve and four further NZ MRs. Finally, the cost to local rock lobster fishers resulting from the displaced fishing effort once the TMR had been established was estimated. This research found that the TMR pre-establishment cost was approximately NZ$508,000, and the establishment process cost was approximately NZ$353,000. The annual management costs across the five reserves ranged between NZ$43,200 and NZ$112,500 between 2008/09 and 2010/11. The annual fishers displacement cost at TMR was approximately NZ$22,000 per annum. This research showed that on a unit area basis, small MRs in NZ are just as expensive to maintain as large MRs. This study also highlighted how volunteer effort helped to considerably reduce the monetary cost of the MR pre-establishment process. This research increases our understanding of establishment and management costs, and supports future planning of MRs both within NZ and internationally.  相似文献   
130.
谢广龙  姜娇  吴小平  欧阳珊 《海洋科学》2015,39(11):126-131
作者于2013年5月至6月调查了位于江西北部地区岩溶地貌陆生贝类资源,共采得陆生贝类63种及亚种(含5个未定种),分别隶属于12科21属,其中1个新种,即石钟山弯螺(Sinoennea shizhongshanensis sp.nov),优势种为雪土鸥螺(Georissa niva)、细纹喇叭螺(Boysidia gracilis)、囊喇叭螺(Boysidia dorsata)和灰尖巴蜗牛(Bradybaena ravida ravida)。区系成分以东洋界成分为主,占总种类数的61.90%。计算了江西北部地区岩溶地貌陆生贝类多样性指数,其中Margalef丰富度指数(dMA)为2.205~4.273,Shannon-Wiener多样性指数(H′)为1.960~3.374,Pielou均匀度指数(Jsw)为0.448~0.681。与邻近自然保护区比较,江西北部地区岩溶地貌陆生贝类较为丰富,与其他自然保护区物种相似性较低。  相似文献   
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