中国水土保持科学2024，Vol.22Issue(1)：12-20,9.DOI:10.16843/j.sswc.2023055
松阔混交对侵蚀退化地土壤有机碳和微生物群落结构的影响
Effect of coniferous and broadleaf tree mixture on soil organic carbon and microbial community composition in eroded and degraded lands
摘要
Abstract
[Background]Vegetation types play an important role in stimulating the carbon sequestration potential of eroded and degraded soil.However,how the changes of tree species in subtropical forest ecosystems affect the accumulation of soil organic carbon(SOC)in the surface soil of eroded and degraded red soil and its microbial mechanism are still unclear.Changting county of Fujian province is a typical eroded and degraded area of red soil in China and a key area of stand transformation.[Methods]Field investigation and sample collection were conducted in different age groups(19 and 39 years)Pinus massoniana pure plantation and P.massoniana and Schima superba mixed plantation.Soil samples were collected in top 0-10 cm layers to measure SOC content,microbial community and related environmental factors.Among them,the microbial community was measured by phospholipid fatty acid(PLFA)method.Correlation analysis and structural equation modeling were used to analyze the relationship between SOC and environmental factors and microbial community composition.[Results]1)There were no significant differences in SOC content between pure and mixed plantations after 19 years of restoration,while SOC content of the mixed plantation after 39 years of restoration were 39.8％,48.0％and 93.6％higher than that of the pure plantation after 19 years of restoration,the mixed plantation after 19 years of restoration,and the pure plantation after 39 years of restoration(P＜0.05).2)SOC content was significantly and positively correlated with soil microbial biomass carbon,microbial biomass nitrogen,total phospholipid fatty acids,mineral nitrogen(N)and bacteria,and significantly negatively correlated with the ratio of litter C/N to fungal bacteria(F/B).3)Structural equation model analysis showed that litter C/N was the trigger factor for the change of SOC and mineral nitrogen was the key factor for the change of microbial community structure in the process of stand transformation.The litter C/N directly drove the change of SOC mass fraction(-0.35*),or indirectly regulated the changes of F/B,arbuscular mycorrhizal fungi and bacteria by mineral nitrogen(-0.70***).The above factors explained 86.8％of the variation of SOC mass fraction.[Conclusions]Mixed coniferous and broad leaf tree species promote SOC accumulation in eroded degraded land,and its effectiveness increases with the restoration years.The possible mechanism could be that the S.superba litter is continuously introduced,which significantly reduces C/N of litter,enhances the source of microbial nutrients and N availability and changes microbial community structure,ultimately increases SOC mass fraction.Under the background of"Double Carbon"in China,a multi-species mixture will become a key way to improve forest quality and SOC sequestration in eroded and degraded areas.关键词
土壤有机碳/针阔混交/林龄/微生物群落组成/凋落物质量/马尾松人工林/侵蚀退化地Key words
soil organic carbon/coniferous and broadleaf tree mixture/stand age/microbial community composition/litter quality/Pinus massoniana plantation/eroded and degraded soil分类
林学引用本文复制引用
王慧钦,吕茂奎,姜永孟,吴君梅,朱洪如,张世良,邓翠,谢锦升..松阔混交对侵蚀退化地土壤有机碳和微生物群落结构的影响[J].中国水土保持科学,2024,22(1):12-20,9.基金项目
国家自然科学基金重点项目"亚热带森林恢复过程中植物来源的底物质量对稳定性土壤有机质的影响机制"(32030073) （32030073）
福建省林业科技计划项目"长汀马尾松低效林森林质量精准提升抚育改造技术及模式优选"(2021FKJ16) （2021FKJ16）
