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101.
The karst landscape in the interior of the Philippines' Bohol Province represents one of the world's premier kegelkarst (cone karst) environments. Government efforts to protect some of this karst, exemplified by the establishment of the Rajah Sikatuna National Park and the Chocolate Hills Natural Monument, have proven to be significant catalysts of social conflict. In Bohol there is a long history of traditional land tenure, which has recently been supplanted by a Westernized model. Protected area establishment is a response to deforestation, agricultural exploitation and uncontrolled quarrying. However, the imposition of protective legislation to prevent further degradation has disenfranchized and marginalized many local farmers and residents. The conflict between the obligation of the State to ensure environmental protection and the perceived property rights of landowners and farmers has provoked an escalation in civil unrest and armed conflict. 相似文献
102.
Eastern and southern coastal zones of Laizhou Bay are the most representative seawater intruded areas in the world, with two intrusion sources of contemporary seawater and paleobrine. In order to reveal the complicated hydrochemical changing process and the mechanism of fresh groundwater being polluted by saltwater, we conducted long-term observation and hydrochemical analysis at four observing sections of typical salt-fresh water transitional zone. The study indicates that seawater and brine intrusion processes have different hydrochemical features, and that ion exchange and adsorption actions between water and aquifer produce great influence on the intrusion. 相似文献
103.
东北农牧交错区水分条件的空间分异及其对土地利用的影响 总被引:2,自引:2,他引:2
大气降水、土壤水分和干燥度指数是在经度方向上控制区域景观格局的主要因素。本文运用最新的调查统计资料,对东北农牧交错区降水、土壤潜在蒸散量、干燥度指数及农作物生长期间土壤水分盈亏量的时间分布进行了分析;提出了研究区内作物生长季期间土壤潜在蒸散量的空间分布规律和干燥度指数的时空变化情形。结合水分条件的空间分布,提出了5种土地利用区域组合类型。 相似文献
104.
西南地区山地不同土地退化类型特征及调控途径 总被引:4,自引:7,他引:4
土地退化不仅是目前全还需性的重大环境问题之一,而且也是重大的社会和经济问题之一,西南地区的土地退化是以水力侵蚀为主要动力形成的,文中简述了西南地区的土地退化状况,选择了4个(楚雄市、遂宁市,毕节地区及元谋县)山地不同土地退化类型进行分析,讨论了土 退化过程,提出了土地退化调控途径。 相似文献
105.
106.
宜溧地区中生代侵入体经地面调查和对比分析,依据花岗岩类岩石谱系单位划分原则,可划分为2个超单元(序列)、7个单元以及1个独立侵入体和2类脉岩.戴埠序列岩石化学特征为钙碱质,平桥序列为弱碱质,反映两个序列岩浆有着明显的差异,组合变异图进一步表明两序列的岩浆演化机理不同,是不连续和彼此独立存在.戴埠序列为轻稀土富集型,平桥序列属于重稀土富集型,应归属A型花岗岩系列. 相似文献
107.
地表复杂地区煤田地震勘探方法及效果 总被引:2,自引:6,他引:2
以宁夏、山东的煤矿地震勘探为例,介绍了复杂地表工区地震勘探的方法与地质效果。 相似文献
108.
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
109.
110.
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