Effects of soil warming and increased precipitation on greenhouse gas fluxes in spring maize seasons in the North China Plain

Gong Wu; Xian-Min Chen; Jun Ling; Fang Li; Feng-Yuan Li; Leanne Peixoto; Yuan Wen; Shun-Li Zhou

doi:10.1016/j.scitotenv.2020.139269

Effects of soil warming and increased precipitation on greenhouse gas fluxes in spring maize seasons in the North China Plain

Sci Total Environ. 2020 Sep 10:734:139269. doi: 10.1016/j.scitotenv.2020.139269. Epub 2020 May 8.

Authors

Gong Wu¹, Xian-Min Chen¹, Jun Ling¹, Fang Li¹, Feng-Yuan Li¹, Leanne Peixoto², Yuan Wen³, Shun-Li Zhou⁴

Affiliations

¹ College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.
² Department of Agroecology, Aarhus University, 8830 Tjele, Denmark.
³ College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China; Scientific Observing and Experimental Station of Crop High Efficient Use of Water in Wuqiao, The Ministry of Agriculture and Rural Affairs, Wuqiao, 061802, China; Innovation Center of Agricultural Technology for Lowland Plain of Hebei, Wuqiao, 061802, China. Electronic address: wenyuan@cau.edu.cn.
⁴ College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China; Scientific Observing and Experimental Station of Crop High Efficient Use of Water in Wuqiao, The Ministry of Agriculture and Rural Affairs, Wuqiao, 061802, China; Innovation Center of Agricultural Technology for Lowland Plain of Hebei, Wuqiao, 061802, China. Electronic address: zhoushl@cau.edu.cn.

PMID: 32450404
DOI: 10.1016/j.scitotenv.2020.139269

Abstract

Climatic changes, such as global warming and altered precipitation are of major environmental concern. Given that ecosystem processes are strongly regulated by temperature and water content, climate changes are expected to affect the carbon (C) and nitrogen (N) cycles, especially in agricultural systems. However, the interactive effects of soil warming and increased precipitation on greenhouse gas emissions are poorly understood, particularly in the North China Plain (NCP). Therefore, a field experiment was conducted over two spring maize seasons (May-Sept.) in 2018 and 2019. Two levels of temperature (T0: ambient temperature; T1: increase on average of 4.0 °C) combined with two levels of precipitation (W0: no artificial precipitation; W1: +30% above ambient precipitation) were carried out in the NCP. Our results showed that soil warming significantly promoted cumulative N₂O and CO₂ emissions by 49% and 39%, respectively. Additionally, increased precipitation further enhanced the N₂O and CO₂ emissions by 54% and 14%, respectively. This suggests that high soil temperature and water content have the capacity to stimulate microbial activities, and thus accelerate the soil C and N cycles. Soil warming increased CH₄ uptake by 293%, but increased precipitation had no effect on CH₄ fluxes. Overall, soil warming and increased precipitation significantly enhanced the GHG budget by 39% and 16%, respectively. This study suggests that climate warming will lead to enhanced GHG emissions in the spring maize season in the NCP, while increased precipitation in the future may further stimulate GHG emissions in a warming world.

Keywords: Agricultural ecosystem; Altered rainfall; Climate warming; GHG emissions; Spring maize.