Effects of restoration measures on soil organic carbon fractions in degraded grasslands in China

doi:10.13287/j.1001-9332.202511.002

Abstract

Abstract: Reseeding, fertilization, and fencing are widely used restoration measures for degraded natural grasslands. Soil organic carbon fractions serve as key indicators for evaluating carbon turnover and sequestration during the restoration of degraded grasslands. Clarifying the impacts of various restoration measures on soil organic carbon fractions can provide a scientific basis for selecting appropriate restoration strategies. Based on 269 data pairs from 73 papers, we evaluated the effects of three restoration measures-reseeding, fertilization, and fencing-on soil organic carbon fractions in degraded natural grasslands in China. The results showed that reseeding significantly increased soil total organic carbon by 18.7%, dissolved organic carbon by 12.4%, and easily oxidizable carbon by 17.7%. Fertilization significantly increased easily oxidizable carbon by 15.5% and light fraction organic carbon by 11.5%, but significantly reduced microbial biomass carbon by 15.5%. Fencing significantly increased dissolved organic carbon by 12.7%, microbial biomass carbon by 17.8%, and particulate organic carbon by 14.7%, while significantly reduced light fraction organic carbon by 9.7%. Under different environmental conditions, reseeding significantly enhanced soil organic carbon content, whereas fencing markedly enhanced soil microbial biomass carbon. In contrast, the effects of fertilization on soil organic carbon fractions exhibited considerable uncertainty. Correlation analysis indicated that soil dissolved organic carbon, light fraction organic carbon, and mineral associated organic carbon significantly increased with increasing total soil organic carbon content, whereas microbial biomass carbon, easily oxidizable carbon, and particulate organic carbon remained relatively stable. Soil moisture and ammonium content are key factors influencing changes in soil organic carbon during the restoration of degraded grasslands.

Key words: degraded grassland, reseeding, nitrogen fertilization, fencing, soil organic carbon fraction, meta-analysis

GUO Zihua, HAO Huanhuan, MA Jie, ZHOU Ao, CUI Qingliang, CHEN Xiaopeng, ZHAO Xiang. Effects of restoration measures on soil organic carbon fractions in degraded grasslands in China[J]. Chinese Journal of Applied Ecology, 2025, 36(11): 3327-3338.

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