川西高山树线群落交错带地被物及土壤的水文效应

摘要

采用样带法,以川西米亚罗林区鹧鸪山高山树线群落交错带为研究对象,分析交错带地被物和土壤的持水特性及其变化规律.结果表明:地被通物最大持水量为33.55～140.03 t·hm-2,暗针叶林>林线>树线>密灌丛>草甸>疏灌丛,暗针叶林枯落物最大持水量显著高于疏密灌丛和草甸;林线地被物拦蓄降水的作用最明显;暗针叶林以苔藓层和枯落物层具有最大有效拦蓄效果,林线和树线以苔藓层具有最大有效拦蓄效果,疏密灌丛以枯落物层具有最大有效拦蓄效果,高山草甸草本层、苔藓层、枯落物层有效拦蓄效果相当;0～30 cm土壤饱和蓄水量都在2 000 t·hm.以上,暗针叶林>林线>疏灌丛>密灌丛一草甸>树线;各群落0～30 cm土层非毛管持水量为575.89～801.46 t·hm-2,表现为暗针叶林>疏灌丛>树线>密灌丛>林线>草甸.%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.