兰州市南北两山人工灌木林地土壤水分动态

 通过定位监测与对比分析,对兰州市南北两山不同生境下柠条和柽柳林地的土壤水分变化情况及土壤水分亏缺状况进行了研究。结果表明:水分亏缺程度、耗水量、耗水强度、吸水能力、根系周围土壤深层水分下降速度，都表现为：柠条>柽柳\.据此认为，在兰州市南北两山这种较干旱地区，如果立地条件允许，更适宜种植柽柳。土壤水分的季节性变化是降水和植物生长综合作用的结果，降水和植物生长对土壤表层的含水量影响较为显著，而对深层土壤水分的作用不明显。土壤水分的季节变化与降水和植物生长的季节性变化相似，可分为三个时期：春季水分消耗期、夏季水分补给期、秋末冬季土壤水分平稳期。

Soil Water Dynamic in Planted Shrubs in Southern and Northern Mountains of Lanzhou City

By position monitoring and comparative analyzing,we studied the variation and deficit degree of soil water of Caragana Korshinskii and Chinese Tamarisk in southern and northern mountains of Lanzhou city.The results showed that the deficit degree of soil water,the amount and intensity of water consumption,the ability to absorb water and the decrease speed of soil water of deep layer were Caragana Korshinskii>Chinese Tamarisk.So Chinese Tamarisk was more suited to be planted in southern and northtern mountains of Lanzhou.The seasonal variation of soil water was the common result of the rainfall and plant growth,the effect of rainfall and plant growth on soil water change of surface layer was notable,and that on substrate was unconspicuous.The seasonal change of soil water was similar to the seasonal variation of rainfall and plant growth,it could be divided into three periods: consuming period,supplying period and stable period.