Effects of Extreme Weather Events on Nitrous Oxide Emissions from Rice-Wheat Rotation Croplands

Abstract

Nitrous oxide (N₂O) is a potent greenhouse gas, and agroecosystems, particularly rice-wheat rotation systems, are significant sources of its emissions. Climate change is increasing the frequency and intensity of extreme weather events (EWEs) such as droughts, heatwaves, and intense rainfall. This paper investigates the complex effects of these EWEs on N₂O fluxes in rice-wheat rotation croplands. Through a synthesis of existing literature and a proposed methodological framework for field-based research, this study posits that EWEs act as acute perturbations that disrupt the delicate balance between nitrification and denitrification processes, often leading to emission pulses that can offset long-term mitigation efforts. The review highlights that the impact is highly dependent on the timing, intensity, and duration of the event relative to key agronomic practices like fertilization and flooding. The proposed research methodology involves a combination of high-frequency automated chamber measurements, isotopic analysis, and microbial genomic sequencing to disentangle the underlying mechanisms. The anticipated conclusions underscore the need for adaptive nitrogen management strategies to enhance agroecosystem resilience in the face of a more variable climate.