麻类作物的土壤碳效应:基于Meta与SWiM方法的定量研究OA

Bast fiber crops exhibit strong stress tolerance and high biomass productivity,and are thus recognized as promising ecological pioneer plants and high-potential carbon sequestration species.Never-theless,current studies on the soil carbon sequestration effects of bast fiber crops are highly heterogene-ous.Moreover,available data are insufficient for standardized integration of several key soil ecological in-dicators,which constrains a comprehensive evaluation of their ecological functions.Based on a global dataset of core experimental observations,this study employed a hybrid analytical approach combining random-effects Meta-analysis and Synthesis without Meta-analysis(SWiM)to quantify the impacts of fi-ber crop cultivation on soil organic carbon(SOC)and associated soil physicochemical properties.The re-sults showed that,compared to conventional non-fiber crops or bare fallow land,bast fiber crops exerted a significant overall positive effect on SOC(lnRR=0.38),yet this effect was highly context-dependent,relying on a comprehensive response to land use type,management intensity,and initial soil background conditions.Subgroup analysis indicated significant differences in carbon sequestration capacity among dif-ferent types of bast fiber crops,with perennial crops(such as ramie and Apocynum venetum)showing considerably higher potential than annual crops(such as jute,flax,and industrial hemp).Furthermore,a trade-off mechanism between biomass input and agronomic disturbance was observed in the soil carbon effects of bast fiber crops:in marginal lands or perennial systems(such as Apocynum venetum primarily used for ecological restoration of saline-alkali soils),low-disturbance management facilitated the stable accumulation of root-derived carbon;by contrast,in annual systems under conventional tillage(e.g.,jute rotation),frequent mechanical disturbance offset the carbon sequestration benefits derived from bio-mass input.SWiM analysis indicated that elevated SOC was not consistently accompanied by reduced soil bulk density or enhanced microbial biomass,demonstrating the asynchronous responses between soil physical structure and biological processes.Our findings suggest that bast fiber crops possess considerable carbon sequestration potential,and their soil carbon effects are comprehensively modulated by agronomic practices.Accordingly,crop management intensity should be prioritized when formulating bast fiber crop-based strategies for carbon sequestration and soil remediation.