Revegetation drives the accrual and stabilization of organic carbon in biocrusts and subsoils in the Tengger Desert, north China

作者：Xiaojun Li, Qun Guo, Rongliang Jia, Yanhong Gao · 发表于：Geoderma · 年份：2025 · DOI：10.1016/j.geoderma.2025.117437 · 被引用次数：9 · 研究领域：Biocrusts and Microbial Ecology、Ecosystem dynamics and resilience、Aeolian processes and effects

Revegetation serves as a critical strategy for desertification reversal and ecosystem restoration in global drylands, which facilitates the development of biological soil crusts (biocrusts) thereby significantly influencing C accumulation and persistence in biocrusts and subsoils. However, the quantitative aspects of SOC accrual and its stabilization mechanisms during biocrust development process following revegetation remain poorly understood. In this study, we investigated the temporal evolution of particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) fractions in biocrusts and the underlying soil layers (0–2 and 2–5 cm) along a 68-year revegetation chronosequence in the Tengger Desert. We aimed to elucidate the mechanisms governing the accumulation and stabilization of SOC in biocrust profiles in these fragile ecosystems by analyzing the relationships between SOC fractions and biotic and abiotic factors. Results revealed substantial SOC accumulation across all layers, with biocrusts showing a 91.77-fold increase over the study period compared with the 38.33– and 7.07-fold increases in the 0–2 and 2–5 cm layers, respectively. MAOC concentrations increased significantly from 1.14 to 5.65 g kg −1 in biocrusts, 0.001 to 1.49 g kg −1 in 0–2 cm soil, and 0.002 to 0.33 g kg −1 in 2–5 cm soil. Consequently, the MAOC proportion of total SOC ranged from 19.89 %–37.36 % in biocrusts, 1.46 %–41.99 % in 0–2 cm soil, and 1.59 %–30.96 % in 2–5 cm soil after 68 yea...