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611.
Yongjun Yang Xuefeng Ren Shaoliang Zhang Fu Chen Huping Hou 《Environmental Earth Sciences》2017,76(6):245
A practical issue is present in sustaining and rehabilitating the ecologically vulnerable post-mining area in which the environmental condition varies spatially and therefore influenced by multiple factors. This paper attempts to integrate the ecological vulnerability assessment and rehabilitation treatment to assist land managers in revealing vulnerable features along with developing treatments of vulnerability mitigation. Using a post-mining site in a mountainous area in western China as study area, an indicator system and framework for assessing and reducing vulnerability were developed based on a vulnerability analysis. Geo-informatics, such as satellite image processing and spatial analysis, were employed to perform the assessment and planning. It was found that higher exposure and sensitivity are the main causes of increased vulnerability in a seriously disturbed post-mining area. Rehabilitation treatments were arranged spatially and structurally based on the framework of vulnerability mitigation. A pre-evaluation of the effectiveness shows this type of rehabilitation has a convergence effect that clusters and lowers the ecological vulnerability index (EVI). The average value of EVI will be reduced by 15.02% if the minimum standards of rehabilitation can be completed. Altogether, an integration of rehabilitation treatments and the quantification of vulnerability in a spatially explicit manner are critical for planners to gain more insight into ecological vulnerability in post-mining area, which provides guidance to simplify rehabilitation planning with respect to vulnerability mitigation. 相似文献
612.
在对胶东地区成矿地质背景、各种致矿地质-构造事件在时间和空间上的耦合、金矿床点时空结构、内在成生联系及时空配置关系研究的基础上,厘定了胶东金矿的概念、特征及主要表现形式,并对其进行了阐述,系统地提出了胶东地区金矿成矿的理论体系,即独具特色的四位一体构造叠置成矿背景、挤压-伸展手风琴式构造-岩浆-成矿作用方式和壳-幔流体多种来源的成矿物质,概括起来就是地质条件、定位方式和物质来源的有机耦合共同构成了胶东地区金矿成矿理论体系,这一理论解释了为何在该区形成巨量金矿的原因,是对胶东地区金矿理论研究的创新性成果。 相似文献
613.
Earth surface processes and their effects on human behavior in monsoonal China during the Pleistocene-Holocene epochs 总被引:1,自引:1,他引:0
Huayu Lu Haixin Zhuo Wenchao Zhang Shejiang Wang Hongyan Zhang Xuefeng Sun Xin Jia Zhiwei Xu Xianyan Wang 《地理学报(英文版)》2017,27(11):1311-1324
There is a wide diversity of landforms in China. The topography of three major terraces, decreasing in height stepwise from west to east, was formed by the early Miocene. With the commencement of the Great Northern Hemisphere Glaciations (GHGs) and the glacial-interglacial cycles in the Pleistocene, thick loess deposits accumulated in north China, and fluvial terraces were formed and lakes expanded and contracted in eastern and central China. The earliest evidence of hominins in China is dated to ~1.7 Ma; they occupied the monsoon-dominated region for a long interval, until the late Pleistocene, ~50 ka. In this study, we investigated a large area rich in the relics and artifacts of early man. The results indicate that the early humans occupied riverine areas, especially medium-sized fluvial basins, and lake shores. Even in the relatively recent geological past, the occupation and abandonment of settlements were directly forced by the shifting of sand dune fields in the desert-loess transitional zone, which in turn was closely associated with variations in the monsoon climate and vegetation patterns. Our observations indicate that landforms were one of the main determinants of early human behavior, in that loess tableland, large alluvial plains, desert-Gobi areas, and the Tibetan Plateau, were not suitable environments for early human settlement. We infer that the early humans in China adapted their behavior to specific landforms and landform processes. The monsoon climate, which shapes the large-scale step-like pattern of fluvial landforms, promotes vegetation coverage and dominates soil formation, provides a crucial context for early human adaptation. The adaptation of early humans to earth surface processes in East Asia is investigated for the first time in this study. Future investigations will provide further information that will increase our understanding of the linkage between early human behavior and landform processes in East Asia. 相似文献
614.
焦作市雷暴潜势预报及临近监测预警系统 总被引:6,自引:0,他引:6
在对焦作市雷暴气候特征分析的基础上,利用T213预报场资料,制作焦作市雷暴趋势预报;采取双判据修正K指数,提出焦作市雷暴稳定度界定指标,做雷暴潜势预报。对1984—2004年的历史资料,分别计算出30个物理量场,形成1°×1°格点资料开展雷暴强度等级判别;综合卫星、雷达、闪电定位仪资料,建立雷暴监测预警系统。该系统采用VB语言编程,根据每天08时、20时MICAPS资料自动完成天气分型、物理量计算、预报指标提取和预报方法的判别,输出预警结论,制作雷暴落区预报。在2005—2006年预报工作中取得较为满意的效果。 相似文献
615.