排序方式: 共有79条查询结果,搜索用时 15 毫秒
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Todaysustainabledevelopmentiscurentlypromoted,butprohibitedbyfragileenvironment.Soinrecentyears,thestudyincludingformationre... 相似文献
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江爱良 《成都信息工程学院学报》2000,15(1):46-52
ENSO事件(包括厄尼诺,与其相反的拉尼娜以及南方涛动)不但影响赤道东太平洋海域的渔业生产,还和地球上许多地区的气候异常现象有关,进而影响到全球环境尤其是生态环境。有人认为ENSO是地球上对于生物界最巨大的一种扰动。本文介绍了1982~1983年与1997~1998年的ENSO事件对于世界各地生态环境的影响。 相似文献
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西南丘陵山地区土地整理与区域生态安全研究 总被引:38,自引:6,他引:38
开展土地整理是实现土地可持续利用的重要途径,不同区域土地整理的目标、任务侧重点各不相同。对于生态脆弱、生态区位非常重要的西南地区而言,其丘陵山地区土地整理的目标必须与区域生态安全的目标相一致。本文从国际国内土地整理的发展趋势以及土地整理目标区域分工的角度,论述西南丘陵山地区土地整理与区域生态安全之间的关系,提出西南丘陵山地区土地整理的首要目标是确保区域生态安全,小流域土地整理是实现该区域生态安全的典型模式。 相似文献
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40a来江河源区的气候变化特征及其生态环境效应 总被引:68,自引:19,他引:68
通过江河源区分布的5个气象台站有关气温与降水的多年数据,分析了近40a来江河源区的气候变化特征,结果表明,近40a来江河源区气候变化的总趋势是气温升高,降水量增加,但降水量的增加主要体现在春季降水和近15a来冬季降水的明显增加上,对植被生长起重要作用的夏季降水量却呈明显减少趋势;江河源区20世纪80年代10a平均气温比50年代高0.12~0.9℃,大部分地区高于0.3℃,属于青藏高原高温区或升温幅度最大的地区之一,平均升温0.44℃,明显比全国平均升温0.2℃要高出一倍,在这种背景下,与植被生长关系密切的4、5月和9月气温呈现持续下降态势,江河源区脆弱的生态环境体系对气候的这种变化响应强烈,冰川退缩,多年冻土消融加剧,导致大范围高寒草甸与草原被植退化。 相似文献
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安溪县光德村地氟病区生态地球化学特征 总被引:5,自引:2,他引:3
在安溪县光德村地氟病区进行生态地球化学调查发现,岩石、土壤、饮用水、水稻、蔬菜中F含量较高,而Cu、Mo、Ca等人体必需的元素严重缺乏;饮用水中F严重超标, F-高达4.18 mg/L,达地下水Ⅲ类标准的4倍之多,且水质pH低于饮用水标准的下限6.5,属酸性水质,不适合饮用,该地区特殊的生态地球化学环境是导致地氟病的主要原因。 相似文献
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Hydrological effects of groundwater abstraction near a Danish river valley have been assessed by integrated hydrological modelling. The study site contains groundwater‐dependent terrestrial ecosystems in terms of fen and spring habitats that are highly dependent on regional and local scale hydrology. Fens are rare and threatened worldwide due to pressures from agriculture, to lack of appropriate management and to altered catchment hydrology. A solid foundation for hydrological modelling was established based on intensive monitoring at the site, combined with full‐scale pumping tests in the area. A regional groundwater model was used to describe the dynamics in groundwater recharge and the large‐scale discharge to streams. A local grid refinement approach was then applied in a detailed assessment of damage in order to balance the computational effort and the need for a high spatial resolution. A considerable flow reduction in the natural spring was monitored during a full‐scale pumping test while no significant effects on the water table in the fen habitats were observed. A modelled abstraction scenario predicted a lowering of 2–3 cm in the centre of the main fen area during summer periods. The predicted change in water table conditions in the fen habitat is compared to the variability found in 35 Danish fens, and the ecological response is discussed based on statistical water‐level vegetation relations. The results provide a rare quantitative foundation for decision making in relation to management of groundwater‐dependent terrestrial ecosystems. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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