毛竹林细根生物量及其周转

Fine Root Biomass and Turnover in Moso Bamboo Plantation in Huitong Forest Station,Hunan Province

通过连续土钻取样法,对湖南会同林区集约经营毛竹林地土壤细根生物量及其动态特征进行研究。结果表明:毛竹林细根生物量为7.7349t.hm-2,其中活细根和死细根分别占91.5%和8.5%,并且毛竹林0～20cm层活细根和死细根生物量分别占林地活细根和死细根总量的57.9%和60%。毛竹林活细根和死细根生物量在1年中有明显的季节变化规律,其变化范围分别为4.8647～10.7964和0.3538～1.0057t.hm-2,基本上2—6月份呈上升趋势,到6月份出现最高峰值,8—12月份下降,次年2月为最低值。采用改进的最大值、最小值法计算模型计算出毛竹林细根年生长量、年分解量和年周转率分别为6.895,0.3124t.hm-2和0.93次.a-1。

Fine root biomass and turnov＇er in an intensive management Moso bamboo plantation of Huitong were investigated with the coring soil sample method. The results showed that the average biomass of finerroots was 7.734 9 t·hm^- 2, with living fine root and dead fine root occupied 91.5% and 8.5%, respectively. The fine root was mainly distributed in the 0 - 20 cm top soil. The annual change of living and dead fine root biomass in the Moso bamboo plantation had obviously seasonal variation and their variation ranges were 4.864 7 ～ 10.796 4 t·hm-2 and 0.353 8 - 1.005 7 t·hm-2 , respectively. The fine root biomass increased from February to June, decreased from August to December. This study for the first time reported that fine root growth rate and decomposition rate of Moso bamboo plantation were 6.895 t·hm-2a-1 and 0.312 4 t＇hm-2a-1, respectively. The annual turnover of fine root in the Moso bamboo plantation was 0.93 times· a- 1