生物炭施用两年后对热带地区稻菜轮作土壤N_(2)O和CH_(4)排放的影响  

Effects of Biochar Application Two Years Later on N_(2)O and CH_(4) Emissions from Rice-Vegetable Rotation in a Tropical Region of China

作　　者：胡煜杰 唐瑞杰 胡天怡 陈绮琦 汤水荣 伍延正 孟磊[1] HU Yu-jie;TANG Rui-jie;HU Tian-yi;CHEN Qi-qi;TANG Shui-rong;WU Yan-zheng;MENG Lei(College of Tropical Crops,Hainan University,Haikou 570228,China)

机构地区：[1]海南大学热带作物学院,海口570228

出　　处：《环境科学》2024年第2期929-939,共11页Environmental Science

基　　金：海南省自然科学基金青年基金项目(320QN196);海南省自然科学基金高层次人才项目(420RC749);国家自然科学基金项目(41661051,42067008);海南省耕地保育重点实验室开放课题项目(HAAS2022PT0103)。

摘　　要：通过探究生物炭施用两年后对海南典型稻菜轮作模式土壤氧化亚氮(N_(2)O)和甲烷(CH_(4))排放的影响,旨在明确生物炭在该模式下对温室气体排放的长期效应,可为我国热带地区稻菜轮作系统N2O和CH_(4)减排提供理论依据.田间试验共设置4个处理,分别为:不施氮肥对照(CK)、施氮磷钾肥(CON)、施氮磷钾肥配施20 t·hm^(-2)生物炭(B1)和施氮磷钾肥配施40 t·hm^(-2)生物炭(B2)处理.结果表明:(1)相较于CON常规施氮处理,B1和B2添加生物炭处理显著减少了早稻季32%和54%的N_(2)O排放,但在晚稻季B1和B2处理显著增加了31%和81%的N_(2)O排放,辣椒季N_(2)O的累积排放量则显著高于早稻和晚稻季,且B1处理显著减少了35%的N_(2)O的排放,B2处理相较于CON处理无显著性差异;(2)B1和B2比CON处理显著减少了早稻季63%和65%的CH_(4)排放,在晚稻季B2处理显著增加了41%的CH_(4)排放,B1处理相较于CON处理无显著性差异,辣椒季各处理CH_(4)的累积排放量无显著性差异;(3)晚稻季贡献了稻菜轮作系统主要的总增温潜势(GWP),CH_(4)的排放量决定了GWP和温室气体排放强度(GHGI)的大小.生物炭施用两年后,B1降低了整个稻菜轮作系统的GHGI,B2增加了GHGI,并达到显著水平,但B1和B2处理在早稻季和辣椒季显著降低了GHGI,仅B2处理在晚稻季增加了GHGI;(4)B1和B2相较于CON处理显著增加了早稻产量33%和51%,且B1和B2处理显著增加辣椒季产量53%和81%,晚稻季除不施氮肥CK处理外,其它处理产量无显著性差异.研究结果表明,热带地区稻菜轮作系统温室气体排放的大小主要取决于晚稻季的CH_(4)排放,而生物炭施用两年后仅低量生物炭配施氮肥有显著的减排作用,但高低量生物炭配施氮肥对早稻和辣椒季作物增产具有持续性.The effects of biochar application on soil nitrous oxide(N_(2)O)and methane(CH_(4))emissions in a typical rice-vegetable rotation system in Hainan after two years were investigated.The aim was to clarify the long-term effects of biochar on greenhouse gas emissions under this model,and it provided a theoretical basis for N_(2)O and CH_(4) emission reduction in rice-vegetable rotation systems in tropical regions of China.Four treatments were set up in the field experiment,including no nitrogen fertilizer control(CK);nitrogen,phosphorus,and potassium fertilizer(CON);nitrogen,phosphorus,and potassium fertilizer combined with 20 t·hm^(-2) biochar(B1);and nitrogen,phosphorus,and potassium fertilizer combined with 40 t·hm^(-2) biochar(B2).The results showed that:①compared with that in the CON treatment,the B1 and B2 treatments significantly reduced N_(2)O emissions by 32% and 54% in the early rice season(P<0.05,the same below),but the B1 and B2 treatments significantly increased N_(2)O emissions by 31% and 81% in the late rice season.The cumulative emissions of N_(2)O in the pepper season were significantly higher than those in the early and late rice seasons,and the B1 treatment significantly reduced N_(2)O emissions by 35%.There was no significant difference between the B2 and CON treatments.②Compared with that in the CON treatment,B1 and B2 significantly reduced CH_(4) emissions by 63% and 65% in the early rice season,and the B2 treatment significantly increased CH_(4) emissions by 41%in the late rice season.There was no significant difference between the B1 and CON treatments.There was no significant difference in cumulative CH_(4) emissions between treatments in the pepper season.③The late rice season contributed to the main global warming potential(GWP)of the rice-vegetable rotation system,and CH_(4) emissions determined the magnitude of GWP and greenhouse gas emission intensity(GHGI).After two years of biochar application,B1 reduced the GHGI of the whole rice-vegetable rotation system,and B2 increased the

关 键 词：热带地区 生物炭 稻菜轮作 氧化亚氮(N_(2)O) 甲烷(CH_(4)) 全球增温潜势(GWP) 

分 类 号：X16[环境科学与工程—环境科学]