Effects of revegetation on soil organic carbon composition and stability in the southern edge of the Tengger Desert
Revegetation is an effective way to reverse desertification,promote soil organic carbon sequestration and address climate change in arid and semi-arid regions.However,the effectiveness of SOC in improving soil quality and mitigating climate change are largely dependent on the composition and stability of SOC.In this study,we investigated the contents of SOC,mineral-associated organic carbon(MAOC),and particulate organ-ic carbon(POC)in the 0-10 cm soil layer of sand-fixing vegetation areas in a chronosequence along the south-ern edge of the Tengger Desert,and the relationship between SOC and its fractions and biotic and abiotic factors were analyzed.The results showed that:the contents of SOC,MAOC,and POC,as well as the proportion of MAOC to total SOC were significantly higher in the sand-fixing vegetation areas compared to mobile sand dune(MSD),and they notably increased with time during the revegetion process,while an opposite trend was found for the proportion of POC to SOC.After 41 years of revegetation,the contents of SOC,MAOC,POC increased dramatically from 0.27,0.009,0.26 g·kg-1 in MDS to 2.86,1.03,1.83 g·kg-1,respectively,representing in-creased by 9.59,113.44,6.04 times,respectively.The proportion of MAOC to SOC ranged from 3.35％to 36.47％,suggesting a gradual enhancement in SOC stability as vegetation restoration progressed.Pearson corre-lation coefficient analysis and structural equation modeling further indicated that variations in MAOC and POC contents and their proportions to SOC were intimately linked to changes in vegetation characteristics,soil physi-cochemical properties,microbial community composition,enzyme activity,and microbial biomass carbon de-rived from revegetation.Among these factors,soil physicochemical properties were the key driving factor,with standardized overall effects on MAOC and POC of 0.965 and 0.86,and-0.172 and 0.281,respectively.Our find-ings indicate that revegetation is an effective to enhance carbon sink potential and promote the long-term seques-tration of SOC in arid sandy regions.
soil organic carbonmineral-associated organic carbonclay and siltstabilityrevegetationthe Tengger Desert
NETL
NSTL
万方数据
