黄河上游退耕还林地枯落物层持水特性研究

Water Holding Characteristics of Litter Layer on Converted Land in Upper Reaches of the Yellow River

对黄河上游的青海省大通县退耕还林地枯落物层的容水特性进行了研究。结果表明,(1)植物群落枯落物层厚度随着林龄的增加而增加;枯落物蓄积量由4.19t/hm2增加到59.91t/hm2。(2)枯落物未分解层、半分解层容水量分别以青海云杉、青海云杉+白桦天然次生林最大,分别为27.22,60.48t/hm2,而青海云杉+沙棘人工林和白桦+青杨+沙棘的退耕地最小,分别为6.85,4.75t/hm2。对未分解层、半分解层蓄积量与容水量进行拟合,相关系数均在0.96以上。(3)退耕地人工群落的枯落物平均厚度已达到天然群落的44.20%,平均容水能力达到天然林群落的33.28%。(4)枯落物容水量与林龄、群落生物量、枯落物厚度、枯落物蓄积量均呈达到极显著相关水平。

The water holding characteristics of litter layer on the land from the converting cropland into forest land project in Datong County in the upper reaches of the Yellow River are studied experimentally.As time lasts,the thickness of litter layer increases and the litter layer storage capacity increases from 4.19 to 59.91 t/hm2.The maximum water holding capacities in the undecomposed and half-decomposed litter layers for Picea crassifolia and Picea crassifolia + Betula platyphylla natural communities are 27.2...