当代新疆洪旱灾害扩大化：人类活动的影响分析

1980′s以来新疆洪旱灾害损失存在扩大化的趋势，这与我国及世界其它地区洪旱灾害增多的趋势相一致。造成当代新疆洪旱灾害增多、灾损扩大的原因除了全球变暖影响外，人类活动的加剧导致新疆生态环境严重退化、绿洲无度扩张致使临灾区域扩大是新疆近期洪旱灾害增多的主要原因。此外，对未来新疆的洪旱趋势进行初步展望，认为在全球和局域人类活动继续加剧的情况下，未来新疆气候会更加不稳定，降水变率增加，洪旱极端事件会增多，若能采取适当的应对措施，洪旱灾害损失会有一定程度的下降。

Recent Magnification of Flood and Drought Calamities in Xinjiang, An Analysis of Anthropogenetic Effects

Since 1980's, there is a magnifying trend of the flood and drought calamities in Xinjiang, which is concordant with that that is occurring in China or in the world. Usually, the global warming is considered as the cause of this trend. However, local human activities are also main reasons of this trend, which should be detected carefully. Therefore, the aim of this paper is to examine the human causes of recent magnification of the flood and drought calamities in Xinjiang based on some statistic data. Generally, magnification of the natural calamity is accompanied by the place change of the human activities in arid land. In the ancient time, the first thing human had to do was probably to choose a safe place for their living. At that time, therefore human lived on some places where the influence of natural hazard was seldom exerted on the people. As the time passing, the human's ability to tame and to affect the nature is increasing with the advancement of the technology. The scope of human activity expands as the man move forward to the center of desert along the river. Thereby, the risk encountering the extreme geophysical event is increased. At present times, the rapidly growing human impacts on ecosystem of the planet are further accelerated. Since 1950, a series of environmental issues, including serious desertifacation, saltification, dust storm, etc., have occurred in Xinjiang owing to the rapidly increase of population and immoderate expansion of the irrigation farmlands. The degradation of environment has become the main restricts of economic development of Xinjiang, which therefor has decreased the ability of human to mitigate the impacts of disasters. This study reveals that the recent magnification of the flood and drought calamities in Xinjiang can be imputed to the rapidly growing of population, the immoderate expansion of the farmland, the inappropriate policies and so on. Although, global change has also exerted, to some extent, impacts on this magnifying. A preliminary prospect to the future of the trend of the flood and drought influence is also outlined in this paper.