文献类型：期刊文献

英文题名：N-fixing species outperform non-N-fixing species in promoting soil organic carbon stability via enhancing edaphic-litter nitrogen availability in Eucalyptus plantations

作者：Fu, Daihan[1] Ming, Angang[2,3] Cao, Haoyang[1] Huang, Runxia[1] Fu, Hao[2,3] Shu, Weiwei[2,3] Wang, Zhichao[1] Zhu, Wankuan[1] Du, Apeng[1] Xu, Yuxing[1]

第一作者：Fu, Daihan

通信作者：Xu, YX[1]

机构：[1]Chinese Acad Forestry CAF, Res Inst Fast Growing Trees RIFT, State Key Lab Efficient Prod Forest Resources, Zhanjiang 524022, Guangdong, Peoples R China;[2]Guangxi Youyiguan Forest Ecosyst Res Stn, Pingxiang 532600, Guangxi, Peoples R China;[3]Chinese Acad Forestry, Expt Ctr Trop Forestry, Pingxiang 532600, Guangxi, Peoples R China

年份：2026

卷号：23

外文期刊名：TREES FORESTS AND PEOPLE

收录：Scopus(收录号：2-s2.0-105023508769);WOS:【ESCI(收录号:WOS:001636513700002)】；

基金：Financial support for this study was provided by grants from the China National Key R & D Program during the 14th Five-year Plan Period (2023YFD2201005) ; Special Funds for the Basic Research and Development Program of the central non-profit research institutes of China (CAFYBB2024MA018, CAFYBB2024QF006) ; Forestry Ecological Monitoring Network Platform Construction Project, and the Operation Project for Guangdong Zhanjiang Eucalyptus Forest Ecosystem National Positioning Observation and Research Station.

语种：英文

外文关键词：Carbon sequestration; Tree species; Soil aggregates; Mixed plantations; Microflora

摘要：Aims: Mixed planting is a more favorable approach than monocultures for soil organic carbon (SOC) sequestration; however, due to the diversity in mixed-species assemblages, the underlying mechanisms remain unclear, hindering afforestation schemes that protect SOC stocks. Methods: A 13-year mixed-species experiment was conducted in a subtropical region, focusing on a Eucalyptus urophylla x E. grandis pure plantation (PP), a Eucalyptus and nitrogen-fixer Erythrophleum fordii mixed plantation (EE), and Eucalyptus and non-nitrogen-fixer Castanopsis hystrix mixed plantation (EC), by measuring SOC in bulk soil and aggregates, followed by partitioning SOC into active carbon pools (labile carbon pool I [LPI-C] and labile carbon pool II [LPII-C]) and a recalcitrant carbon pool (RP-C). The present study considered various environmental factors, including plants, soil, microflora, and enzyme activities, to analyze the processes and factors underlying SOC sequestration within different mixed plantation modes. Results: Mixed forests improved SOC sequestration by optimizing soil aggregate stability, increasing fertility, relieving phosphorus limitation, and stimulating microbial activity. SOC sequestration in EE soils was driven by both fine root biomass and litter quality, whereas SOC sequestration in EC soils relied on fine root elongation. Only nitrogen-fixing mixtures enhanced SOC stability, favoring long-term carbon storage. The high carbon (C)/ nitrogen (N) ratio in the soil and the nitrogen-rich environment promoted an increase in Gram-negative bacteria, achieving stable SOC storage by forming large aggregates. Conclusion: The present study highlights the advantages of mixed-species afforestation in SOC sequestration and reveals the unique value of nitrogen-fixing species in long-term carbon storage. The present findings offer theoretical and practical guidance for scientific afforestation and enhancing the carbon sink function of forest ecosystems.