秸秆还田和水旱轮作模式对稻季土壤温室气体排放的影响  

Greenhouse gas emissions of rice season soils under different paddy-upland rotation systems

作　　者：邓姣 李心雨 朱杰 杨伟 李成伟 蒋梦蝶 朱波 聂江文 刘章勇 DENG Jiao;LI Xin-yu;ZHU Jie;YANG Wei;LI Cheng-wei;JIANG Meng-die;ZHU Bo;NIE Jiang-wen;LIU Zhang-yong(Hubei Collaborative Innovation Center for Industrialization of Major Grain Crops,College of Agronomy,Yangtze University,Jingzhou,Hubei 434200,China;Hubei Xiangyang Academy of Agricultural Sciences,Xiangyang,Hubei 441100,China)

机构地区：[1]长江大学农学院主要粮食作物产业化湖北省协同创新中心,湖北荆州434200 [2]湖北省襄阳市农业科学院,湖北襄阳441100

出　　处：《植物营养与肥料学报》2024年第2期268-278,共11页Journal of Plant Nutrition and Fertilizers

基　　金：国家重点研发计划项目(2022YFE0209200-04);国家自然科学基金项目(31870424);长江大学湿地生态与农业利用教育部工程研究中心开放基金项目(KF202309,KF202308)。

摘　　要：【目的】探究不同水旱轮作模式下,冬季作物秸秆还田对后茬水稻季作物产量和温室气体排放的影响,为长江中游稻田选择适宜的秸秆还田方式和农业可持续生产提供科学依据。【方法】田间试验在湖北荆州进行,设置水稻–小麦(稻麦)、水稻–油菜(稻油)和水稻–紫云英(稻肥)3种水旱轮作模式,每个模式下设置冬季作物收获后秸秆还田和不还田处理。在秸秆还田后的水稻季,采用静态暗箱—气相色谱法连续监测稻田中甲烷(CH_(4))和氧化亚氮(N_(2)O)排放量,在水稻分蘖期、抽穗期、成熟期采集0—5、5—10、10—20 cm土层样品,测定微生物量碳(MBC)、可溶性有机碳(DOC)、铵态氮(NH_(4)^(+)-N)和硝态氮(NO_(3)^(-)-N)含量,收获期测定水稻产量。【结果】秸秆还田和不同轮作模式对后茬水稻产量均无显著影响。与稻肥轮作相比,在秸秆还田条件下稻油和稻麦轮作水稻季土壤CH_(4)和N_(2)O排放分别高出44%~58%和17%~30%,在秸秆不还田条件下则分别高出58%~72%和15%~22%。与秸秆不还田相比,秸秆还田条件下3种轮作模式平均CH_(4)和N_(2)O排放分别增加26%~39%和20%~29%。秸秆还田条件下,稻油和稻麦轮作稻季土壤全球增温潜势(GWP)和温室气体排放强度(GHGI)分别比稻肥轮作高出14%~19%和12%~19%,秸秆不还田条件下分别高出18%~23%和15%~24%。与秸秆不还田相比,秸秆还田条件下3种轮作模式稻季土壤平均GWP和GHGI高出31%和32%,同时土壤硝态氮、微生物量碳和可溶性有机碳含量均显著提高。此外,稻麦轮作土壤微生物量碳和可溶性有机碳含量显著高于稻肥、稻油轮作。相关性分析表明,秸秆还田条件下,CH_(4)和N_(2)O排放与NO_(3)^(-)-N呈极显著正相关(P<0.01),而秸秆不还田条件下CH_(4)排放与NO_(3)^(-)-N呈极显著正相关(P<0.01),N_(2)O排放与NH_(4)^(+)-N呈极显著正相关(P<0.01)。【结论】水稻季土壤CH_(4)和N_(2)O的排放与土壤可�【Objective】The research investigated the greenhouse gas emissions in the subsequent rice season under different paddy-upland rotation systems and straw(green manure)return condition,to propose an environmental friendly rotation mode in the middle reaches of the Yangtze River.【Method】A field experiment was conducted in Jingzhou of Hubei Province.The rice-wheat(RW),rice-rape(RR)and rice-Chinese milk vetch(RC)rotation systems were arranged,and under each rotation system,the upland crop straws were returned to or removed out of the field.In the following rice season,the methane(CH_(4))and nitrous oxide(N_(2)O)emissions in paddy fields were continuously monitored using static dark box-gas chromatography.At the tillering,heading and maturing stages of rice,soil samples were collected at 0−5 cm,5−10 cm,and 10−20 cm layers for the determination of microbial biomass carbon(MBC),dissolved organic carbon(DOC),NH_(4)^(+)-N and NO_(3)^(-)-N content,and rice yield were investigated at harvest.【Results】Straw return and rotation patterns did not affect rice yield significantly,but did in CH_(4) and N_(2)O emissions.Compared with no straw return,the CH_(4) and N_(2)O emissions in the three rotation systems under straw return increased by 26%−39%and 20%−29%on average,respectively.Compared with RC rotation,the CH_(4) and N_(2)O emissions in RR and RW rotation systems were increased by 44%−58%and 17%−30%under straw return,and by 58%−72%and 15%−22%under no straw return,respectively.The global warming potential(GWP)and greenhouse gas emission intensity(GHGI)of RR and RW rotation systems were 14%-19%and 12%-19%higher than those of RC rotation system,respectively.Regardless of the effect of rotation system,the GWP and GHGI of subsequent rice under straw returning were 31%and 32%higher than those under no straw returning,respectively.On average,the contents of NO_(3)^(-)-N,MBC and DOC in three rotation systems in different soil layers under no straw returning were higher than those under no straw returning.T

关 键 词：轮作模式 秸秆还田 增温潜势 排放强度 土壤可溶性有机碳 微生物量碳 有效氮 

分 类 号：S511[农业科学—作物学] S141.4