景电灌区开发建设对区域生态环境的影响

利用１９９４￣１９９６年实地抽样调查资料和全县２５ａ的气象，农林业生产统计资料，对景泰县引黄新灌区开发建设以来区域内的生态环境变化进行分析，结果表明，灌区建设使区域内形成了以新型人工植被和被改造保护的自然植被协调发展的植被景观；灌溉面积增加地和地表植被盖度的提高，使区域内地表蒸发量明显降低，大风日数，沙暴日数，年均风速最大风速值有所下降，并使年降水量，空气温湿度在一定程度上妥生了变化，而人为作用强

EFFECT OF EXPLOITATION AND CONSTRUCTION OF JINGTAI IRRIGATION AREA ON LOCAL ECO ENVIRONMENT

This paper analyses the changes of eco enviroment in the new irrigated area of Jingtai County since its construction.The results show that,a new vegetation landscape was formed in combination of a man made vegetation and improved natural vegetation.That increased the irrgation area and raised the cover rate of vegetation,the evaporation capacity dropped considerably meanwhile,the day number of strong wind,the day number of dust and sand storm,and the annually average speed of winds were decreased.And the precipitation,air temperature and humidity changed to certain degree.The areas with stronger activities and longer time of exploitation generally and higher cover rate of vegetation,the better effect of transformation and the more improved fertility in soil.However,it was found that irrigation could cause secondary salinization in the area of bad drainage.