Abstract:

In this paper, ground coverage and the soil water-holding capacity of Zhegu alpine treeline ecotone in Miyaluo forest region of western Sichuan were studied using belt transect method. The results showed that maximum water holding capacity of ground coverage was 33.55-140.03 t ·hm^-2 with a trend of dark-conifer forest> timberline>treeline >dense shrub > apline meadow > sparse scrub. Maximum water holding capacity of litter was significantly higher in dark-conifer forest than in shrubs and meadow. Interception capacity of ground coverage in timberline was most obvious; from the perspective of modified interception amount, moss and litter layers were both dominant in the dark-conifer forest, the moss layer was dominant in the treeline and timberline, the litter layer was dominant in the shrub, interception capacity of herb layer, moss layer and litter layer in alpine meadow was all similar. Maximum water holding capacity of 0-30 cm soil layer was higher than 2 000 t ·hm^-2 with a trend of dark-conifer forest> timberline > sparse scrub >dense shrub≈ apline meadow>treeline. In 0-30 cm soil layers, non-capillary moisture capacity was 575.89-801.46 t ·hm^-2 with a trend of dark-conifer forest> sparse shrub> treeline> dense shrub> timberline> apline meadow.

Key words: alpine treeline ecotone, ground coverage, maximum water holding capacity, modified interception amount