Abstract:

The emission of methane from paddy fields is regarded as one of the most significant sources of carbon emissions in agricultural production. Consequently, modern agricultural researchers are focusing on how to effectively reduce methane emissions without sacrificing grain yield in rice production. This review summarizes recent advances in understanding methane production, emission, and strategies for reducing emissions in paddy fields, based on current research findings. It clarifies the processes of methane production, oxidation, and emission, as well as the key influencing factors. The production and emission of methane are closely correlated with the physicochemical properties of soil (including pH, key enzyme activities, water content, temperature, oxidation-reduction potential, and texture), rice varieties (including root morphology and activity, root exudation, aerenchyma, harvest index, and plant height), cultivation techniques (including crop rotation patterns, irrigation and fertilization management practices, and planting methods), and climate factors (including air temperature, atmospheric carbon dioxide concentration, and UV-B radiation). In this review, management practices aiming at decreasing methane emissions are summarized from the perspectives of new variety breeding and comprehensive regulation methods: 1) Selecting evaluation parameters based on the differences in methane emission levels among various rice varieties and breeding new rice varieties that achieve high grain yield with low methane emissions; 2) Exploring new substances that can reduce methane emissions in paddy fields; 3) Investigating innovative technologies for low-carbon cycled cultivation and breeding of rice and fish systems that promote low-carbon circulation, enhance carbon fixation capacity, and reduce methane emissions in paddy soil, as well as the integration of multiple cultivation methods. Additionally, we should explore the pathways for reducing methane emissions in paddy fields according to different production environments in rice-growing regions and establish a high-efficiency comprehensive cultivation regulation system. Reasonable suggestions for future research directions regarding the reduction of methane emissions in paddy fields are presented. It is hoped that this paper will provide not only theoretical evidence for high-yield rice cultivation with lower methane emissions but also technical references for achieving the national "dual carbon" goals.

Key words: paddy field, methane, emission, reducing emission measurement

摘要：

稻田甲烷(CH₄)排放是农业生产中主要碳排放源之一。如何在保证丰产的前提下，有效降低水稻生产中CH₄的排放量成为现代农业科研工作者研究的焦点。围绕稻田CH₄的产生、排放与减排方式，本文综述了目前稻田CH₄产排的相关研究进展，阐述了稻田CH₄的产生、氧化过程、排放方式及其主要影响因素。稻田甲烷的产生排放与土壤理化性状(pH值、关键酶活性、含水量、温度、氧化还原程度、质地等)、水稻品种(根系形态活力与分泌物、通气组织、收获指数、株高等)、栽培技术(轮作模式、水肥调控、种植方式)、气候变化(气温、大气CO₂浓度、UV-B辐射)等因素密切相关。本文重点从选育高产低排新品种、研发稻田CH₄减排新物质、稻-渔低碳循环种养、土壤持续固碳减排、多种栽培调控方式耦合的新技术等方面入手，系统总结了稻田CH₄减排的技术措施，提出应根据不同稻区的生产特点，因地制宜，探索建立稻田CH₄减排高效综合技术体系。在此基础上，讨论了未来重点研究方向，以期为水稻丰产减排生产提供技术支撑，为顺利实现国家“双碳”目标提供有益参考。

关键词: 稻田, 甲烷, 排放, 减排措施