亚热带森林逆向演替对土壤碳贮量的影响

A study on the change of the soil carbon storage during inverse succession in subtropical forests in Ailao Mountain,Southwest China

选择了亚热带森林逆向演替过程中的原生林、次生林和人工林作为研究对象,开展亚热带森林逆向演替过程中土壤有机碳贮量的研究.研究结果表明：自原生林到人工林,0-100 cm土壤容重增加,土壤有机碳含量显著减少;土壤碳贮量次序却为原生林（445.7 Mg·hm-2）,茶园（427.7 Mg·hm-2）和次生林（314.5 Mg·hm-2）依次减少,表明在逆向演替过程中,因人为干扰和管理使得人工林土壤碳储蓄能力高于次生林.0-40 cm的土壤占100 cm土壤剖面碳的比例随着逆向演替过程逐渐减少：亚热带常绿阔叶林（63.0%）〉滇南山杨次生林（57.2%）〉茶园（52.4%）;土壤容重,土壤有机碳含量,土壤碳贮量剖面动态有林间差异.但在60 cm以下层间差异不显著,表明逆向演替过程对深层的土壤碳贮量影响小,在未来的研究中需关注本区域60 cm以上土壤碳库对土地利用变化和气候变化的反馈.

To study the variation of soil carbon storage during inverse succession in subtropical forests,primary forest（ subtropical evergreen broad- leaved forest）,Populus rotundifolia forest（ secondary forest） and tea plantation（ planted forest） as the typical forests were selected in Ailao Mountain and soil organic carbon content,soil bulk density and carbon storage by layers of soil profile from 0 to 100 cm depth were measured. The results showed that： soil bulk density increased but the soil organic carbon contentdecreased from primary forest to tea plantation,while soil organic carbon storage ranked decreasingly as primary forest（ 445.7 Mg·hm-2）,tea plantation（ 427.7 Mg·hm-2）,and secondary forest（ 314.5 Mg·hm-2,which shows that during the inverse succession of subtropical forests,the carbon storage in planted forests is greater than the secondary forests due to fertilizer and forests management.The carbon storage of the first 40 cm soil profile to that of 100 cm soil profile decreased as subtropical evergreen broad-leaved forest（ 63.0%）,secondary forest（ 57.2%） and tea plantation（ 52.4%）.Soil bulk density,soil organic carbon content and soil organic carbon storage dynamic of soil profile layers vary during different forest types,but are not significantly different at depth below 60 cm. It suggests that the inverse succession does not influence the soil carbon storage in deep soil layers.It is recommended to focus on the feedback of soil carbon storage of the soil from 0 to 60 cm depth to the change of land use and climate in Ailao Mountain.