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111.
The Apuseni Mountains constitute one of the most interesting parts of the Carpathians in terms of landscape, biodiversity and culture. Yet dislocations are now severe and there are development threats which also require a significant response. On the one hand there are some severe pollution problems associated with mining areas developed in the communist period which require remedial action and the cases of Roşia Montana and Zlatna are discussed. On the other hand, there are forest and pasture zones – especially the Padiş Plateau – which are coming under heavy pressure from farmers seeking to enhance their incomes following the decline of mining and manufacturing which has left many households without salaries. At the same time, tourist pressure is growing. Actions are already being taken to limit pollution damage and develop sustainable landuse practices. There is a national park project linked with nature reserves comprising picturesque landscapes, a rare flora and fauna and distinct geological and palaeotological formations (including fossil ice). There are major tourist attractions and with proper management they could become part of a development programme of the countryside. However it is essential that all stakeholders adopt sustainable practices and this means that official programmes – including the future national park authority administration's work in environment protection and tourism management – are backed up by Environmental Non-Governmental Organisations (ENGOs). The paper reviews their diverse activities and concludes that they are making a very substantial contribution in ensuring that the potentials of isolated regions can be utilised in a manner consistent with nature conservation. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
112.
山地蒸发的计算   总被引:8,自引:0,他引:8  
傅抱璞 《气象科学》1996,16(4):328-335
本文研讨了山地下垫面蒸发的计算,提出了根据迳流系数和降水强度确定计算蒸发公式中与地形、植被、土壤等下垫面特性降水性质有关的参数的方法,经实际检验,结果令人满意。  相似文献   
113.
火山地区二维自然电位异常反演   总被引:2,自引:0,他引:2       下载免费PDF全文
将线性反演理论与正则化法相结合,提出一个火山地区二维自然电位(SP)异常反演方法.地下岩浆活动(对流体)是引起自电异常的极化源,反演的目的是计算地下视极化强度分布和极化源中心位置.可以通过用已知的各种资料改变地下极化源区域(简称源区)的方式来进行多次反演,以便获得一个比较合理的地下视极化强度分布模型.最后,分别给出意大利和墨西哥的两个火山地区的自然电位异常分析结果.  相似文献   
114.
50km范围内2级以上地震年频数的空间扫描图,揭示了1970年以来晋北及其附近地区5级以上地震发生前,震中附近地区出现的地震空区,文中展示了从1970-1995年每年的空间扫描图,供分析对比。  相似文献   
115.
计算伸展断层底界面深度的作图法简介   总被引:2,自引:0,他引:2  
本文简介了计算正断层底界滑脱面深度的3种几何作图法。其中,M.W.Kilsdonk(1989)在Davison(1985)方法基础上作出的修正方法,简便且较准确。运用这种方法计算的鲁西地区深层次滑脱面深度与壳内低速层深度吻合。  相似文献   
116.
本文基于地质环境是由诸多因素有机组合而成,其质量也是各因素质量的复杂组合,是一种模糊现象,难以精确评价,但又存在明显差异的认识,采用模糊数学理论,即以环境地质亚区为单元,考虑多因素的综合影响。采用数量化的动态聚类法,对晋陕蒙接壤地区地质环境质量进行了评价:包括自然条件下地质环境质量评价和煤炭、水资源开发后地质环境质量的相对变化评价。  相似文献   
117.
ABSTRACT

In humid regions, surface runoff is often generated by saturation-excess runoff mechanisms from relatively small variable source areas (VSAs). However, the majority of the current hydrologic models are based on infiltration-excess mechanisms. In this study, the AGricultural Non-Point Source Pollution (AGNPS) model was used to integrate the VSA concept using topographic wetness index (TWI). Both the original and AGNPS-VSA models were evaluated for a small agricultural field in Ontario, Canada. The results indicate that the AGNPS-VSA model performed better than original model. The AGNPS-VSA model predicted that only the saturated portion of the field with higher TWI values produced runoff, whereas the original AGNPS model showed uniform hydrologic response from the entire field. The results of this study are important for accurately mapping the locations of VSAs. This new model could be a powerful tool in identifying critical source areas for applying targeted best management practices to minimize pollutant loads to receiving waters.  相似文献   
118.
ABSTRACT

Data on global population distribution are a strategic resource currently in high demand in an age of new Development Agendas that call for universal inclusiveness of people. However, quality, detail, and age of census data varies significantly by country and suffers from shortcomings that propagate to derived population grids and their applications. In this work, the improved capabilities of recent remote sensing-derived global settlement data to detect and mitigate major discrepancies with census data is explored. Open layers mapping built-up presence were used to revise census units deemed as ‘unpopulated’ and to harmonize population distribution along coastlines. Automated procedures to detect and mitigate these anomalies, while minimizing changes to census geometry, preserving the regional distribution of population, and the overall counts were developed, tested, and applied. The two procedures employed for the detection of deficiencies in global census data obtained high rates of true positives, after verification and validation. Results also show that the targeted anomalies were significantly mitigated and are encouraging for further uses of free and open geospatial data derived from remote sensing in complementing and improving conventional sources of fundamental population statistics.  相似文献   
119.
四川少数民族自治区域旅游开发与贫困缓解   总被引:10,自引:0,他引:10  
四川少数民族自治地区是一个贫困面大、贫困程度深的区域。但它有着非常丰富的自然生态和民俗风情旅游资源,旅游业有着其他产业所无法比拟的资源优势。近年来,旅游业已成为区域新的经济增长点和国民经济的先导产业,将旅游开发与扶贫有机结合应该成为缓解贫困的有效的途径。但旅游扶贫功效的发挥是有条件的,并不是所有的旅游形式都具有同等的扶贫功效。为此文章论述了有利于贫困缓解的旅游发展战略。  相似文献   
120.
朔黄铁路与沿线地带经济发展   总被引:1,自引:0,他引:1  
该文分析朔黄铁路的功能及其对沿线地区基础设施建设、商贸旅游业、工农业和城镇发展的影响,提出沿线地区经济发展应采取的措施。  相似文献   
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