六盘山不同森林群落地被物的持水特性

Water holding capacity,absorption rate and saturated water stock of a different forest's floor were studied in Liu Pan Mountain.The results showed that at the beginning of dipping in water,the absorption rate was high,and then it leveled off with the time going on.Un-decomposed litter and half-decomposed litter were saturated with water in 2 and 4 h,respectively.Except Pinus tabulaeformis litter,water holding capacity of half-decomposed layer was 3.5 to 8 times as the dried weight and the water holding capacity of half-decomposed layer was 1.8 to 7.6 as the dried weight.The water holding capacity of broad-leaved litter was greater more than that of needle litter,and the capacity of moss was greater than branch litter.The water absorption rate was regressed to the time with the equation of Y=a+bt-1.Litter saturated water reflects hydrologic function.Litter saturated water Larix principis-rupprechtii and Quercus Liaotungensis were larger than other species in the valley.Additionally,there was abundant grass stock in Larix principis-rupprechtii and Betula platyphylla forest,and the grass water stock was respectively 5.4 t·hm-2,3.9 t·hm-2,which accounted for 9.3% and 12.0% of that of litter in the two forests.