Revisiting Sustainable Development of Dry Valleys in Hengduan Mountains Region

Dry valleys are a striking geographic landscape in Hengduan Mountains Region and are characterized by low rainfall, desert type of vegetation and fragile environment. Past efforts and resources have been concentrated mainly on rehabilitation of degraded ecosystem and fragile environment, particularly reforestation, while socio-economic development has been largely overlooked. Despite successes in pocket areas, the overall trend of unsustainability and environmental deterioration are continuing. It is important to understand that uplift of the Tibetan Plateau is the root cause of development of dry valleys, and development and formation of dry valleys is a natural process. Human intervention has played a secondary role in development of dry valleys and degradation of dry valleys though human intervention in many cases has speeded up environmental degradation of the dry valleys. It is important to understand that dry valleys are climatic enclaves and an integrated approach that combines rehabilitation of degraded ecosystems and socio-economic development should be adopted if the overall goal of sustainable development of dry valleys is to be achieved. Promotion of niche-based cash crops, rural energy including hydropower, solar energy, biogas and fuelwood plantation is recommended as the priority activities.     

台湾地层检讨(续)

所谓‘大寮层’者,以页岩与砂岩之交互层为主,厚约350公尺,在其上部,砂岩发育较佳,而在山下部则反是。砂岩往住带石灰质并含有化石,尤其在上部有富含Ditrupa sp之灰质的砂岩发现,所谓Ditrupa化石带是也。此外尚有下列之化石发现:     

风沙路基施工技术初探

路基施工中保证路基填筑密实度，通常沙土路基采用水夯；普通路基采用振动碾、羊角碾等重型机具振密夯实。但在缺电、缺水，高气温、大风沙的沙漠气候等恶劣的施工条件下，风沙路基的施工如何保证路基填筑的密实度和施工机械在风沙路基上作业而不陷车的问题，就目前没有合适的经验可借鉴，也没有规范可参考。因此把在包西线神木北至延安北段的铁路工程建设中风沙路基施工所取得的经验和施工技术作一介绍。     

青海省沙漠现状及形成与发展趋势

本文根据遥感调查的结果,论述了青海省沙漠的类型、面积及分布规律特征。并通过不同时期的遥感图象,研究了青海湖等地区近三十年沙漠化环境的动态变化规律,从自然和人为因素两方面分析探讨了沙漠形成及发展趋势。     

周末风暴（十）——亲历南极大救险

饮恨雷岛经历了昨晚长城海湾的风雪之夜,奥立格虽疲惫之极,却因出艇搜救未果而久不能眠。清晨7点51分,他突然接到韩国站呼叫,通报长城站在沙坝一带海岸发现遇险小艇物品,并请求加强对阿德雷岛一线继续搜寻。于是他分析了韩国人员在昨夜恶劣暴风雪中翻艇落水可能的过程,很快设想了自己下一步营救计划。8点30分,一辆改装的苏式装甲运兵车,装载着一支由俄罗斯队员为主的7人搜救队,急速向阿德雷     

江苏潮滩沉积物激光粒度仪与移液管-筛析分析结果的对比

激光粒度仪的广泛应用带来了与历史数据的对比问题,因此需要建立激光粒度仪与早期分析结果之间的关系。根据江苏海岸潮滩沉积物样品的激光粒度仪和移液管-筛析法分析,对粒度参数、粒度组分等进行了对比,对两种方法的差异进行了分析。结果表明,对于江苏潮滩沉积物粒度参数中平均粒径的激光粒度仪与移液管-筛析分析结果之间有良好的线性关系;筛分法测得的粗颗粒物质较激光法偏少,而移液管法法测得的细颗粒物质较激光法偏多;将样品分类之后再进行两种方法所获粒度参数的回归分析,相关性得以提高,说明不同粒度组成的沉积物对分析结果的对比有不同的影响。两种方法之间的换算关系不仅与研究区域有关,而且与沉积物本身的粒度组成有关。     

护砂保堤 固我“长城”

84km长的盐场海堤宛如一条巨龙横卧在黄海海岸线上,它不仅为金桥盐业有限公司挡潮抵浪。同时也保护着赣榆、灌云、新浦、连云两县两区2000km^2、150万人口的生命财产安全。     

美国地质勘探局海岸与海洋地质研究--近期重点和成就

本文详细介绍了美国地质勘探局海岸与海洋地质研究项目在环境质量与保护、自然危害与公众安全、自然资源、信息和技术以及未来的研究方面所开展的工作和取得的成就。