Short-term effects of land consolidation of dryland-to-paddy conversion on soil CO2 flux

Xiaoxiao Li; Nan Hui; Yongjun Yang; Jing Ma; Zhanbin Luo; Fu Chen

doi:10.1016/j.jenvman.2021.112691

Short-term effects of land consolidation of dryland-to-paddy conversion on soil CO₂ flux

J Environ Manage. 2021 Aug 15:292:112691. doi: 10.1016/j.jenvman.2021.112691. Epub 2021 May 8.

Authors

Xiaoxiao Li¹, Nan Hui², Yongjun Yang³, Jing Ma⁴, Zhanbin Luo⁵, Fu Chen⁶

Affiliations

¹ Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization, China University of Mining and Technology, Xuzhou, Jiangsu, 221008, China; School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China. Electronic address: lixiaoxiao@cumt.edu.cn.
² School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China. Electronic address: nan.hui@sjtu.edu.cn.
³ School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou, Jiangsu, 221008, China. Electronic address: y.yang@cumt.edu.cn.
⁴ Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization, China University of Mining and Technology, Xuzhou, Jiangsu, 221008, China. Electronic address: jingma2013@cumt.edu.cn.
⁵ College of Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, China. Electronic address: zbluo@nwafu.edu.cn.
⁶ Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization, China University of Mining and Technology, Xuzhou, Jiangsu, 221008, China. Electronic address: chenfu@cumt.edu.cn.

PMID: 33975267
DOI: 10.1016/j.jenvman.2021.112691

Abstract

To improve grain production capacity, many areas in the world are shifting from rainfed agriculture to irrigated agriculture. One example of such land consolidation is dryland-to-paddy conversion. The conversion of land use pattern largely affects the stability of farmland soil, especially the soil carbon cycle. However, the mutual feedback mechanisms between carbon flux variation and environmental factors during the farmland consolidation process are still poorly known. Located in the Huang-Huai-Hai Plain China, Xuzhou is a typical area where dryland-to-paddy conversion are most widely distributed. Therefore, in this study, we have carried out dryland-to-paddy conversion by setting up two isolated rectangular fields one group planting corn in dryland (DL) and another group planting in paddy field (PF) in Xuzhou. Here, we determined the effect of dryland-to-paddy consolidation on soil CO₂ flux in two isolated rectangular fields - the dryland (DL) cultivated with corn and the paddy field (PF) cultivated with rice. Our results showed that the soil carbon flux and temperature followed similar unimodal curves with greater soil CO₂ flux of in PF than in DL. Surprisingly, the land conversion significantly reduced soil microbial biomass carbon and easily oxidized organic carbon by 28.55% and 29.09%, respectively. The structural equation modeling results demonstrated that the changes in soil environmental factors, including temperature, and fungal OTU numbers, were the primary drivers for the soil CO₂ flux and soil carbon pool (P < 0.05). Overall, this study improves the understanding of the ecological impact of dryland-to-paddy conversion, providing insights into low-carbon agriculture and climate mitigation.

Keywords: Huang-huai-hai plain; Land consolidation; Land use conversion; Soil CO(2) flux; Soil carbon pool; Structural equation model.

MeSH terms

Agriculture
Carbon / analysis
Carbon Dioxide / analysis
China
Oryza*
Soil*

Substances

Soil
Carbon Dioxide
Carbon