土地利用变化对流域生态需水的影响分析

人类对流域生态系统的干预,导致季节性淹没区减少,天然湿地丧失,生态环境的恶化和生物多样性锐减,土地利用方式发生了剧烈变化。以流域整体性理论、物种多样性理论、物种耐性理论和景观生态学理论为基础,分析了土地利用方式对生态需水的影响。结果表明,河岸天然植被生态系统通过削减洪峰、增补枯水和截留污染物的作用,来影响流域的水量分配和水质改善,使流域受水分不足威胁的程度降低,即在更大的时间与空间尺度上,保证了流域对生态水的需求。因此,为了流域生态系统的可持续发展,应采取保护湿地、河溪森林植被、水陆交错带等合理的土地利用方式。

Effect of land use on ecological water requirement of river basin

The interruption of human with the ecosystem of a river basin will change the land use dramatically such as reducing the seasonal flood area,losing the natural wetland,decreasing the diversity of habitat and biology and so on.Based on the holistic theory of river basin,the biodiversity theory,the patience theory and the landscape ecology theory,the influences of various land uses on ecological water requirement are analyzed.The results prove that the ripatian natural plant ecosystem can allocate the water quantity,improve the water quality of river basin,lower the risk of a river basin threatened by the shortage of water resources, and ensure the ecological water requirement on longer time and wider space scales.So the reasonable measures about land uses including protecting wetland,ripatian forest and island water ecotone should be taken in order to make the ecosystem sustainable development of a river basin.