Spatial distribution of soil organic carbon and its response to forest growth and soil layer in Cunninghamia lanceolata plantations in mid-subtropical China

• Published in: Forest ecology and management Vol. 545; p. 121302
• Main Authors: Wang, Hailun, Wang, Jiachen, Zhang, Ying, He, Gongxiu, Wen, Shizhi
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2023
• Subjects: administrative management; canopy; carbon sequestration; China; Cunninghamia lanceolata; enzyme activity; Forest growth; Redundancy analysis; simulation models; soil density; Soil depth; soil enzymes; Soil organic carbon; soil pH; Stand age; stand development; tree and stand measurements; tree height; China; Soil organic carbon; Forest growth; Soil depth; Stand age; Redundancy analysis
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/j.foreco.2023.121302

•Soil organic carbon distribution in forests responded to external environmental factors.•Forest soil organic carbon distribution exhibited surface aggregation at multiple scales.•Forest growth and soil enzyme activity were important factors affecting soil organic carbon distribution.•The interaction of various environmental factors on soil organic carbon distribution showed a weakening trend. To investigate the effects of stand age and soil layer on the temporal and spatial distribution of soil organic carbon (SOC) in Cunninghamia lanceolata plantations, five experimental plots and 15 soil sampling sites were established in five stands of different ages (3, 6, 9, 15, and 25 years) in Huitong, Hunan Province. Tree diameter at breast height, tree height, canopy density and elevation in sample plots, and soil organic carbon concentrations (SOCC), soil enzyme activity, soil pH, and soil bulk density at 0–15, 15–30, 30–45 cm soil layers were measured during stand development. The change in SOC distribution with stand age and soil layer, and soil enzyme activity were investigated using ANOVA, LSD test, and inter-subject effect test and simulation analysis. The results showed that the SOC distribution in Cunninghamia lanceolata plantations had spatiotemporal heterogeneity and surface aggregation. The SOC increased with increasing stand age and decreased with increasing soil depth. Furthermore, SOCC and SOC density (SOCD) were strongly correlated with environmental factors; however, the interaction between forest growth and soil layer reduced the variation of SOC distribution. Forest growth and soil enzyme activity were important factors that affect the temporal and spatial distribution of SOC. Therefore, the management measures to promote the growth of the plantation and improve soil enzyme activity can enhance the SOC storage capacity from the angle of balancing ecological and economic benefits, and contribute to the achievement of the goal of “carbon neutrality”.