根据河西走廊近年来水资源研究中比较一致的结果,计算了各县市绿洲年、日平均气温≥10℃期间的实际水资源。采用张宝堃和H.L.彭曼的气候学方法,对各县市林木生长期的蒸散耗水量进行了估算,与实测和调查资料对照表明,两种估算值大致可分别反映林木基本正常生长和良好生长对水分的需求。提出了“实际干燥度”和“实际湿润度”的概念,并根据后者确定了各县市绿洲不同气候植被区林木的适生程度,以及应当选择的乔、灌木树种。

According to the recent research on water resources in the Hexi Corridor, Gansu Provin-ce, the author calculated in detail the actual runoffs of rivers in every district and municipa-lily, and the irrigation requirements and the actual water resources of oases during annual and daily mean temperature≥10℃. Using Zhang Baokun and H. L. Penman's climatological method respectively, the author estimated the evapotranspirations of trees during their growing season everywhere. Compared with the observed and investigated data, the value estimated by the former could be considered as the consumption index of arbor that grows fine and forms fuel forest, the value estimated by the latter could be considered as the consumption index of arbor that grows fine and forms timber forest. The evapotranspiration of bush is 1/3-2/3 as many as that of arbor. Based on the fact that there exit bath nonirrigated desert area and irrigable oasis area, the author suggests the concepts of "natural aridity", "natural wettability", "actual aridity" and "ac-tual wettability", and divides both nonirrigated desert area and irrigable oasis area into vari-ous types of climate and vegetation by virtue of these concepts. The results are relatively coin-cided with their physical landscapes. From the analysis, in the Hexi Corridor the wettability in the arid area is equal to the ratio of plantable arbor or bush area to the total area. According to the natural wettability and the actual wettabili}y, the adaptive faculties of trees and what kinds of trees are suitable to plant in both the nonirrigated area and the irrigable oasis area in the Hexi Corridor are determined respectively.