Rainfall increasing offsets the negative effects of nighttime warming on GHGs and wheat yield in North China Plain

Yaojun Zhang,Feng Lin,Wenkai Shou,Carmelo Maucieri

doi:10.1038/s41598-021-86034-3

Abstract

The effects of nighttime warming and rainfall increasing on crop productivity and soil greenhouse gas emissions are few studied. This study was conducted with a field experiment to investigate the effects of nighttime warming, rainfall increasing and their interaction on wheat grain yield, methane (CH4) and nitrous oxide (N2O) emissions during a winter wheat growing season in the North China Plain (NCP). The results showed that nighttime warming and rainfall increasing significantly altered soil temperature and moisture, and thus the CH4 and N2O emissions from the soil. Nighttime warming significantly promoted soil CH4 uptake by 21.2% and increased soil N2O emissions by 22.4%. Rainfall increasing stimulated soil N2O emissions by 15.7% but decreased soil CH4 uptake by 18.6%. Nighttime warming significantly decreased wheat yield by 5.5%, while rainfall increasing enhanced wheat yield by 4.0%. The results indicate that the positive effect of nighttime warming on CH4 uptake and negative effect on wheat yield can be offset by rainfall increasing in the NCP. Generally, rainfall increasing significantly raised the global warming potential and greenhouse gas intensity induced by CH4 and N2O emissions. Overall, this study improves our understanding of agroecosystem C and N cycling in response to nighttime warming and rainfall increasing under future climate change.

Highlights

Climate change, mainly induced by greenhouse gas emissions (GHGs), is expected to increase temperature and alter rainfall pattern worldwide in the future[1,2]
Methane (CH4) and nitrous oxide (N2O) emissions from soils are two important GHGs contributing to global warming and are in turn virtually affected by climate c hange[3]
Most studies on GHGs emissions response to warming have concentrated on grassland, forest and tundra, and the results have shown inconsistent responses of C H4 and N 2O emissions to warming from p ositive[8,9], to n egative[10,11] and no c hange[12,13]

Summary

Introduction

Mainly induced by greenhouse gas emissions (GHGs), is expected to increase temperature and alter rainfall pattern worldwide in the future[1,2]. Studies examining C H4 and N 2O emissions response to warming are still lacking in agricultural field, and they mainly focused on the daily mean temperature increasing[9]. In nighttime temperature during winter and spring seasons, which will give rise to profound impact on wheat production and the soil GHGs emissions[16,18,19]. Few studies explored the C H4 and N 2O emissions from agricultural soil as response to rainfall increasing and the combined effects with nighttime warming. Understanding the winter wheat productivity and GHGs emissions response to nighttime warming and increased rainfall for predicting the climate-driven changes in agroecosystem is necessary. We carried out a field plot experiment to examine the effects of nighttime warming and rainfall increasing on CH4 and N2O emissions and wheat yield. We hypothesized that: (1) both nighttime warming and increased rainfall could stimulate CH4 and N2O fluxes, (2) nighttime warming could decrease wheat yield while rainfall increasing could alleviate the negative effect

Methods

Results

Discussion

Conclusion