火干扰对大兴安岭呼中林区地上死木质残体碳储量的影响

Influence of fire disturbance on aboveground deadwood debris carbon storage in Huzhong forest region of Great Xing'an Mountains,Northeast China

基于野外样点实测数据,分析了不同烈度火烧对大兴安岭呼中林区地上死木质残体碳储量的影响.结果表明:不同烈度的火烧会对地上死木质残体碳储量产生显著影响.兴安落叶松林和针阔混交林(落叶松与白桦)中死木质残体碳储量大小为重度火烧>轻度火烧>未火烧,而白桦林中死木质残体碳储量大小为重度火烧>未火烧>轻度火烧.火干扰能显著改变森林中死木质残体碳储量的组成百分比.随着火烧烈度的增加,枯立木比重显著增大,枯落物比重显著减小,而不同火烧烈度下倒木和树桩的碳储量比重变化不显著.不同烈度的火烧对死木质残体碳储量特征的影响不同,轻度火烧下死木质残体碳储量的空间变异性最高,重度火烧下空间变异性最弱.不同火烧烈度下大兴安岭森林死木质残体碳储量差异显著,在进行森林死木质残体碳储量估算时,需要充分考虑这种差异性.

Based on the field inventory data, the aboveground deadwood debris carbon storage un- der different fire severities was analyzed in Huzhong forest region of Great Xing＇ an Mountains. The results showed that the fire severity had a significant effect on aboveground deadwood debris carbon storage. The deadwood debris carbon storage was in the order of high-severity 〉 low-severity 〉 un- burned in Larix gmelinii stands, and mixed conifer-broadleaf stands （L. gmelinii and Betula platyphylla）, and in the order of high severity 〉 unburned 〉 low-severity in B. platyphylla stands. Fire disturbance significantly changed the component percentage of the deadwood debris carbon stor- age. The component percentage of snags increased and litter decreased with the increasing fire se- verity. Logs and stumps did not change significantly with the increasing fire severity. The spatial var- iation of deadwood debris carbon storage in forests burned with low-severity fire was higher than that in unburned forests. The spatial variation of deadwood debris carbon storage with high-severity fires was lowest. This spatial variation needed to be accounted when calculating forest deadwood debris carbon storage.