羊草草甸草原火烧地凋落物的分解与积累速率变化  

Fire Effects on Decomposition and Accumulation of Litter in Aneurolepidium Chinense Steppe

作　　者：周道玮[1] 周以良[2] 

机构地区：[1]东北师范大学草地所,130024 [2]东北林业大学植物所

出　　处：《草业学报》1993年第4期51-55,共5页Acta Prataculturae Sinica

摘　　要：草原经常着火,火烧是草原生态系统中正常而重要的自然生态因子。羊草草甸草原火烧后土壤温度升高,湿度下降,微生物区系组成也发生显著变化,导致枯落物分解和积累速率产生差异。对比研究表明:火烧地羊草枯落物第一年分解消失率为0.25489g·g^(-1)·a^(-1),第二年为0.17344,而未烧地分别为0.34956和0.19913;火烧地群落枯落物分解消失率第一年为0.40797,第二年为0.25443;未烧地分别为0.46204和0.27003。火烧地群落枯落物干重损失99％需3.6年,而未烧地损失99％需3.3年;火烧地羊草枯落物干重损失99％需5.0年,而未烧地需4.1年。火烧地群落枯落物积累量达到50％稳定需2.0年,未烧地需0.4年,火烧地枯落物积累量达到95％稳定需6.7年,未烧地需6.9年。自火烧后第4年起,火烧效应消失。Fire could rapidly return and release the nutrients and energy accumulated in the litter. Burning in meadow steppe of Aneurolepidium chinense could make 85% dry weight of litter gasificated to the air. The changes of microclimate and flora of microorganism after burning lead to the rate of decomposition and accumulation of the litter changed. The results by comparatively studying showed disappearance rate of litter of A. chinense in burned plot is 0.25489g·g^(-1)·a^(-1) (1st year) and 0.17344g·g^(-1)·a^(-1) (2nd year) VS 0.34956 and 0.19913 in unburned plot, disappearance rate of mixed litter is 0. 40797g·g^(-1)·a^(-1)(1st year) and 0.25443g·g^(-1)·a^(-1) (2nd year) in burned plot VS 0.46204 and 0.27003 in unburned plot. It need 5.0 years for 99% dry weight of litter of A. chinense losted in burned plot VS 4.1 years of that in unburned plot, it need 3.6 years for 99% of dry weight of mixed litter losted in burned plot VS 3.3 years of that in unburned plot. It takes 2.0 years to reach 50% steady state accumulation in burned plot VS 0.4 years in unburned plot, takes 6.7 years to reach 95% steady state accumulation in burned plot VS 6.7 years in unburned plot. From the fourth year after early spring burning, the burning effects disappeared. The nature fire frequence in the region may be four years.

关 键 词：羊草草原 火烧 分解 积累 

分 类 号：S812.8[农业科学—草业科学]