Effect of different vegetation restoration on soil organic carbon dynamics and fractions in the Rainy Zone of Western China. (1st April 2023)

• Record Type: Journal Article
• Authors: Yang, Fan; Zhong, Yujian; Han, Guangzhong; Li, Xiuzhi; Luo, Li; Cai, Xiaomin; Long, Xinyu; Li, Tangli; Huang, Laiming
• Is Part Of: Journal of environmental management. Volume 331(2023)
• Publication Date: 2023-04-01
• Subjects: Grain-for-green project -- Land-use change -- Soil carbon fraction -- Carbon management index; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2023.117296
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Vegetation restoration on purple soil (Eutric Leptic Regosols) slopes aiming at reducing soil erosion in the Rainy Zone of Western China has significantly altered soil organic carbon (SOC) storage and distribution. A better understanding of the effects of different vegetation restoration types on SOC dynamics and fractions is critical in devising better policy to protect or enhance SOC stocks to improve soil quality and ecosystem function. In the present study, total, labile, and non-labile organic carbon (TOC, LC, and NLC), and carbon management index (CMI) of Cryptomeria fortunei (CF), mixed C. fortunei and Betula luminifera (MF), Neosinocalamus affinis (NA), and Camellia sinensis (CS) were compared with those of Zea mays field (ZM) on purple soil slopes in the Rainy Zone of Western China in order to develop more effective ways to implement vegetation restoration in the future. Different vegetation restoration types (CF, MF, NA and CS) increased TOC stock by 47.79%–118.31% and NLC stock by 56.61%–129.52% in the 0–50 cm soil layer compared with that of ZM. The direction and magnitude of changes in LC stock and CMI, however, depended strongly on the vegetation restoration type. Compared with ZM, CF had the largest increase of LC stock and CMI, whereas NA had the largest decrease of LC stock and CMI in the 0–50 cm soil layer. The LC:TOC ratio in four reforested species all declined significantly compared with that of ZM ( p < 0.01), indicating decreased SOC activity after afforestation. The vegetation type and soil depth together explained more than 90% of the changes of TOC and its fractions in the plantations on purple soil slopes. Our study demonstrates that transforming the ZM into the CS is optimal to achieve the sustainable development goal, whereas transforming the ZM into the NA reduces the SOC activity and availability. Highlights: Afforestation promoted accumulation of TOC and NLC irrespective of vegetation types. LC accumulated or decreased after afforestation depended on vegetation types. SOC activity and availability decreased due to declined LC/TOC ratios after afforestation. Transforming cropland to tea plantation is optimal to achieve sustainable development goal.