生物黑炭对滨海盐土区稻田温室气体(CH4、CO2、N2O)排放的影响

Effects of biochar on greenhouse gas(CH4,CO2,and N2O)emissions in a coastal saline rice field

为探究生物黑炭对稻田温室气体(CH4、CO2、N2O)排放和水稻产量的影响,采用静态暗箱-气相色谱法监测滨海盐土区稻田温室气体排放,并分析施用不同比率的生物黑炭对稻田生态系统CH4、CO2和N2O排放、水稻产量、综合温室效应(GWP)以及温室气体强度(GHGI)的影响.田间试验共设4个处理,分别为不施肥(N0)、氮肥(N1)、氮肥+20 t/hm^2生物黑炭(N1B1)和氮肥+40 t/hm^2生物黑炭(N1B2).结果表明:与N0处理相比,N1、N1B1和N1B2处理提高了CH4的累积排放量,涨幅为28.24%-37.81%;显著提高了CO2累计排放量(P<0.05),涨幅为45.41%-120.78%;显著提高了N2O的累积排放量,涨幅为130.60%-226.07%(P<0.05).与N1处理相比,N1B1和N1B2处理分别提高CH4累积排放量的7.46%和1.82%,显著提高了CO2累计排放量50.08%(P<0.05)和51.83%(P<0.05),提高了N2O累积排放量的9.31%和41.40%(P<0.05),显著提高了产量34.66%(P<0.05)和35.25%(P<0.05).与N1处理相比,N1B1和N1B2处理的分别提高了综合温室效应27.13%和25.54%,而降低了温室气体强度5.93%和7.89%.综合来看,在滨海盐土区稻田施用生物黑炭可以提高水稻产量并且降低温室气体强度.

To investigate the effects of biochar on greenhouse gas(CH4,CO2,and N2O)emissions and crop production in rice fields,a field experiment was established to study the influences of biochar amendment on CH4,CO2,and N2O emissions,rice yield,global warming potential(GWP),and greenhouse gas intensity(GHGI)using a static opaque chamber and gas chromatography method in a saline rice field.There were four treatments in the field experiment:non-fertilization(N0),nitrogen fertilizer(N1),nitrogen fertilizer+20 t/hm2 biochar(N1B1),and nitrogen fertilizer+40 t/hm^2 biochar(N1B2).The results showed that the N1,N1B1,and N1B2 treatments increased the cumulative CH4 emission fluxes by 28.24%-37.81%,increased the cumulative CO2 emission fluxes by 45.41%-120.78%(P<0.05),and increased the cumulative N2O emission fluxes by 130.60%-226.07%(P<0.05)compared to those by the N0 treatment.The N1B1 and N1B2 treatments increased the cumulative CH4 emission fluxes by 7.46%and 1.82%,increased the cumulative N2O emission fluxes by 9.31%and 41.40%(P<0.05),and increased the rice yield by 34.66%and 35.25%(P<0.05),respectively,compared to those by the N1 treatment.The N1B1 and N1B2 treatments also increased the GWP by 27.13%and 25.54%and decreased the GHGI by 5.93%and 7.89%,respectively,compared to those by the N1 treatment.In conclusion,the application of biochar in coastal saline rice fields increased rice yield and reduced the GHGI.