Effects of land use and land cover change on soil organic carbon storage in the Hexi regions, Northwest China. (15th June 2022)

• Record Type: Journal Article
• Authors: Li, Yongge; Liu, Wei; Feng, Qi; Zhu, Meng; Yang, Linshan; Zhang, Jutao
• Is Part Of: Journal of environmental management. Volume 312(2022)
• Publication Date: 2022-06-15
• Subjects: LUCC -- SOC storage -- Cropland expansion -- Climate change -- Hexi corridor -- Qilian mountains; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2022.114911
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Soil organic carbon (SOC) storage in arid inland regions is significantly affected by land use and land cover change (LUCC) associated with climate change and agricultural activities. A systematic evaluation to the LUCC effects on SOC storage could enable us to better manage soil carbon pools in arid inland regions. Here, we evaluated the effects of LUCC on SOC storage in the Hexi Regions based on high-resolution SOC and LUCC maps derived from Landsat imagery and digital soil mapping using machine learning algorithm and environmental covariates. The results showed that SOC generally increased from northwest to southeast over the Hexi Regions with an average stock of 7.15 kg C m −2 at a soil depth of 100 cm and a total storage of 2783.05 Tg C. The SOC stock and storage in the Qilian Mountains (mountains) was about 3.90 and 4.55 times higher than that in the Hexi Corridor (plains), respectively. It was estimated that LUCC over the past four decades caused a net increase of 23.41 and 18.19 Tg C in total SOC storage for the Qilian Mountains and Hexi Corridor, respectively. Specifically, the development in grasslands quality as well as the land-use category conversion from the bare land to grassland mainly contributed to the increase in SOC storage of the Qilian Mountains, where the LUCC was mainly driven by climate change. By contrast, the SOC storage change in the Hexi Corridor was mainly associated with the conversion from sandy land and low-cover grassland to cropland as well as sandy land to grassland, being mainly affected by intense cropland expansion and desertification control. Our results highlighted the importance of climate change and cropland expansion in enhancing SOC storage of the Qilian Mountains and Hexi corridor, respectively. Highlights: The high-resolution soil organic carbon (SOC) and land use change maps was used. The Hexi Regions SOC show an increasing trend caused by land use change during 1980–2018. The climate change and cropland expansion enhanced SOC storage of the Qilian Mountains and Hexi Corridor, respectively. The local should balance agricultural and ecological water to further enhance SOC storage.