凋落物输入对木荷林土壤微团聚体有机碳及其化学结合形态的影响  

Effects of Litter Input on Organic Carbon and Its Chemical-Bound Forms of Soil Microaggregate in Schima Superba Forest

作　　者：朱丽琴[1] 黄荣珍[1] 王金平 黄国敏[1] 万鸿宇 林丽靖 Zhu Liqin;Huang Rongzhen;Wang Jinping;Huang Guomin;Wan Hongyu;Lin Lijing(Jiangxi Key Laboratory of Degraded Ecosystem Restoration and Watershed Eco-hydrology,Nanchang Institute of Technology,Nanchang,Jiangxi 330099,China;Shantou Overseas Chinese Economic and Cultural Cooperation Experimental Zone Management Committee,Shantou,Guangdong 515000,China)

机构地区：[1]南昌工程学院,江西省退化生态系统修复与流域生态水文重点实验室,江西南昌330099 [2]汕头华侨经济文化合作试验区管委会,广东汕头515000

出　　处：《水土保持通报》2023年第1期307-313,共7页Bulletin of Soil and Water Conservation

基　　金：江西省教育厅科学技术研究项目“凋落物、细根和菌根输入对退化红壤微生物群落结构的影响”(GJJ190974);国家自然科学基金项目“外源有机碳对红壤退化地微团聚体形成与稳定的影响机制”(31660192)。

摘　　要：[目的]探究地上凋落物、地下根系和菌根输入对红壤恢复林地土壤微团聚体的影响,为退化地进行森林恢复后土壤功能重建和生态系统碳循环提供依据。[方法]以亚热带红壤侵蚀退化地恢复形成的典型阔叶林分木荷纯林为研究对象,设置无凋落物(CT)、菌根(M)、根系+菌根(RM)、地上+地下凋落物(LRM)和地上凋落物加倍(DLRM)5种输入处理,对土壤微团聚体组成、有机碳及其化学结合形态进行分析。[结果]木荷恢复林土壤微团聚体质量百分比、有机碳、钙键结合态有机碳(Ca-SOC)、铁铝键结合态有机碳[Fe(Al)-SOC]和Ca-SOC/SOC在不同处理间均无显著差异(p>0.05);相对于CT,LRM处理使20~50μm和50~200μm粒级微团聚体Fe(Al)-SOC/SOC分别降低了40.06%和46.67%(p<0.05)。土壤微团聚体质量百分比、有机碳、Ca-SOC和Fe(Al)-SOC均随粒级的增大而减小,有机碳及结合态有机碳趋于在较小粒级的微团聚体颗粒组(<20μm)中富集。微团聚体Ca-SOC含量(0.55~1.28 g/kg)远低于Fe(Al)-SOC含量(6.88~13.34 g/kg),但其在不同粒级中的变化幅度大于Fe(Al)-SOC;Ca-SOC/SOC(1.54%~3.44%)亦小于Fe(Al)-SOC/SOC(16.75%~42.54%)。微团聚体质量百分比、有机碳、Ca-SOC和Fe(Al)-SOC两两之间呈极显著正相关关系(r=0.497~0.757,p<0.01)。[结论]木荷恢复林土壤微团聚体及其有机碳受粒级的影响,对地上凋落物、地下根系和菌根的短期输入有所响应,但未达到显著水平,需要在更长的时间尺度上开展研究。[Objective]The effects of changes in aboveground litter,underground roots,and mycorrhizal inputs on soil microaggregates of restored red soil forestland were analyzed in order to provide a basis for soil function reconstruction and understanding the ecosystem carbon cycle after forest restoration of degraded lands.[Methods]The study was conducted in a pure Schima superba forest,a typical broad-leaved forest recovered from eroded and degraded red soil in a subtropical region.Five input treatments were established:no litter(CT),mycorrhiza(M),root+mycorrhiza(RM),aboveground+underground litter(LRM),and double aboveground+underground litter(DLRM).The composition of soil microaggregates,organic carbon,and their chemically bound forms were analyzed.[Results]There were no significant differences in soil microaggregate mass percentage,organic carbon,Ca-SOC,Fe(Al)-SOC,and Ca-SOC/SOC among the different treatments(p>0.05).Compared with CT,LRM reduced Fe(Al)-SOC/SOC of microaggregates of size 20—50μm and 50—200μm by 40.06%and 46.67%,respectively(p<0.05).Soil microaggregate mass percentage,organic carbon,Ca-SOC,and Fe(Al)-SOC decreased as particle size increased,and organic carbon and bound organic carbon tended to be enriched in smaller particle size groups(<20μm).The content of Ca-SOC in microaggregates(0.55—1.28 g/kg)was much lower than observed for Fe(Al)-SOC(6.88—13.34 g/kg),but its variation range in different particle sizes was greater than that of Fe(Al)-SOC.The percentage of Ca-SOC/SOC(1.54%—3.44%)was also less than the percentage of Fe(Al)-SOC/SOC(16.75%—42.54%).Microaggregate mass percentage,organic carbon,Ca-SOC,and Fe(Al)-SOC were positively correlated(r=0.497—0.757,p<0.01).[Conclusion]Soil microaggregates and their organic carbon in a restored S.superba forest were affected by particle size.Both quantities responded to short-term inputs of aboveground litter,underground roots,and mycorrhiza,but did not reach a significant level,and therefore need to be studied over a longer time period.

关 键 词：凋落物 微团聚体 钙键结合态有机碳 铁铝键结合态有机碳 木荷 

分 类 号：S714.2[农业科学—林学]