关键词: 河西走廊, 实际水资源, 林木蒸散量, 实际干燥度, 实际湿润度, 林木适生程度

Abstract: 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.

Key words: The Hexi Corridor, Actual water resource, Evapotranspira}tion of tree, Ac-tual aridity, Actual wettability, Adaptive faculty of tree