Abstract: The study by using associate coefficient and simultaneous emergence percentage showed that on the alpine grassland of east Qilian Mountains, the interspecific relationships in Salix shrub community could be classified into three kinds,i.e., 1) positive association, which was shown from the relationships between the couples of all plant species except those between S. myrtillacea and S. cupularis, and Dasiphora fruticosa and Spiraea alpina at the altitudes of 3 050, 3 100, 3 200 and 3 250 m, and S. ortrepha and Rhododendron capitatum at the altitudes of 3 300, 3 350 and 3 450 m, 2) negative association, which was shown from the relationships between D. fruticosa and S. rehderiana at 3 100 m, D. fruticsa and S. myrtillacea as well as D. fruticsa and S. myrtillacea at 3 150 m, and S. ortrepha and S. cupularis as well as S. rehderiana and R. capitatum at 3 450 m, and 3) neutral association, which was shown from the relationships between the couples of all plant species except those between S. myrtillacea and S. cupularis at 3 050 m, R. capitatum and other shrub plants from 3 100 to 3 250 m, and S. alpina and R.capitatum at 3 400 m.

Key words: Platycladus orientalis, Robinia pseudoacacia, Growth stage, Transpiration pattern, Soil moisture, Time-soil moisture function