光叶苕子覆盖对土壤团聚体不同来源碳积累的影响  

Effects of smooth vetch covering on carbon accumulation from different sources in soil aggregates

作　　者：张萌 程瑞梅[1,2] 沈雅飞[1,2] 陈天 李璟 曾立雄[1,2] 雷蕾 肖文发[1,2] ZHANG Meng;CHENG Ruimei;SHEN Yafei;CHEN Tian;LI Jing;ZENG Lixiong;LEI Lei;XIAO Wenfa(Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration,Ecology and Nature Conservation Institute,Chinese Academy of Forestry,Beijing 100091,China;Co-Innovation Center for Sustainable Forestry in Southern China,Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]中国林业科学研究院森林生态环境与自然保护研究所,国家林业和草原局森林生态环境重点实验室,北京100091 [2]南京林业大学南方现代林业协同创新中心,南京210037

出　　处：《应用生态学报》2025年第1期141-151,共11页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金重点项目(32130074);中央级公益性科研院所基本科研业务费专项(CAFYBB2022XD001)资助。

摘　　要：微生物源碳和植物源碳的积累共同决定了土壤有机碳库的稳定。为探究绿肥覆盖下土壤团聚体不同来源有机碳的积累特征及其相对贡献,本研究在柑橘园中设置野外定位控制试验,以清耕处理为对照,分析光叶苕子覆盖对土壤大团聚体(2~8 mm)、小团聚体(0.25~2 mm)以及微团聚体(<0.25 mm)不同来源有机碳的影响,量化了不同来源有机碳对土壤团聚体总有机碳的贡献,明确了不同来源有机碳积累的驱动因素。结果表明:1)光叶苕子覆盖增加了土壤团聚体真菌残体碳、微生物残体碳含量以及二者对土壤团聚体总有机碳的贡献,其中,微团聚体真菌残体碳、微生物残体碳含量增加幅度最大,分别为76.7%、70.2%;光叶苕子覆盖还提高了土壤团聚体真菌残体碳与细菌残体碳的比值,且比值的变化范围为4.58~4.66,说明真菌残体碳含量较高,主导了微生物残体碳的积累。2)光叶苕子覆盖降低了大团聚体的总木质素酚含量及其对总有机碳的贡献,但显著增加了微团聚体总木质素酚含量,而对微团聚体总木质素酚对总有机碳的贡献无显著影响。3)土壤有机碳和微生物生物量碳是微生物残体碳的重要影响因素,亮氨酸氨基肽酶和交换性钙离子含量的增加提高了微生物残体碳对总有机碳的贡献;络合态铁氧化物含量是提高微团聚体总木质素酚对总有机碳贡献的重要因子。综上所述,光叶苕子覆盖下真菌残体碳主导了土壤团聚体微生物残体碳的积累,大团聚体中植物源碳可能转化为微生物源碳储存在土壤中,微生物源碳将主导土壤团聚体有机碳的变化。The stability of soil organic carbon pool is determined by the accumulations of microbial-and plant-drived carbon. To explore the accumulation characteristics of organic carbon from different sources and their relative contributions in soil aggregates covered by green manure, we conducted a field experiment in citrus orchards with clean tillage treatment as the control, to analyze the effects of smooth vetch covering on the accumulation and relative contribution of microbial-and plant-drived carbon in large macroaggregates(2-8 mm), small macroaggregates(0.25-2 mm) and microaggregates(<0.25 mm), as well as the driving factors behind. The results showed that: 1) Smooth vetch covering increased fungal and microbial necromass carbon and their contributions to total organic carbon in soil aggregates. The increase in microaggregates of fungal and microbial necromass carbon was the most prominent, which reached to 76.7% and 70.2%, respectively. Smooth vetch covering increased the ratio of fungal to bacterial necromass carbon, which ranged from 4.58 to 4.66 across soil aggregates, indicating that fungal necromass carbon led to the accumulation of microbial necromass carbon. 2) Smooth vetch covering decreased the total lignin phenol content and its contribution to total organic carbon in large macroaggregates, but significantly increased the content in microaggregates, with no significant contributions to total organic carbon. 3) Soil organic carbon and microbial biomass carbon were two important factors which influenced microbial necromass carbon. The contribution of microbial necromass carbon to total organic carbon was increased with increasing leucine aminopeptidase and exchangeable calcium contents. In addition, the content of complex Fe oxide played a vital role in increasing the contribution of total lignin phenol to total organic carbon in soil aggregates. In summary, under smooth vetch covering, fungal-derived carbon dominated the accumulation of microbial necromass carbon in soil aggregates. Plant-derived carbon

关 键 词：光叶苕子覆盖 土壤团聚体 微生物残体碳 植物残体碳 土壤有机碳 

分 类 号：S153.6[农业科学—土壤学]