水稻品种对三江平原稻田温室气体排放的影响

Effects of Rice Varieties on Emission of Greenhouse Gases from Paddy in Sanjiang Plain

利用静态箱—气相色谱法研究了三江平原3个主栽水稻品种(空育131、龙粳18、垦鉴稻6)对生长季节稻田CO2、CH4和N2O排放规律、源/汇及其与环境因子关系的影响。结果表明:3个水稻品种的CO2、CH4和N2O平均通量范围分别为405.5～647.2、9.6～20.5 mg.m-2.h-1、4.1～6.3μg.m-2.h-1;空育131 CO2排放通量较龙粳18和垦鉴稻6提高48.6%、59.6%,CH4下降53.2%、27.8%,N2O提高53.7%、46.5%;3个水稻品种CO2、CH4与空气温度或土壤温度有普遍较好的正相关性。生长季,3个水稻品种均为CO2、CH4、N2O的排放源(14.6～23.3、345.1～737.8、0.148～0.227 kg.hm-2.a-1),所产生的温室效应相当于26.9～32.7 t.hm-2.a-1CO2,GWP组成结构均以CO2和CH4占绝对优势。

An experiment was conducted to study the effects of three rice varieties （Ky131, Lj18 and Kj6） on seasonal dynamics of CO2, CH4 and N2O emissions from paddy soil, source or sink, as well as their relationships with environmental factors by the method of static chamber and gas chromatography in growing season in Sanjiang Plain. Result showed that the average fluxes of CO2, CH4 and N2O emissions from rice field of Kyl31, Lj18 and Kj6 ranged from 405.5 to 647.2 mg·m^-2·h^-1, 9.6 to 20.5 mg · m^-2 · h^-1 and 4.1 to 6.3 μg · m^-2 · h^-1 in growing season, respectively. The flux of CO2 from Ky131 was 48.6% and 59.6% higher, the flux of CH4 was 53.2% and 27.8% lower, and the flux of CH4 was 53.7% and 46.5% higher than those from Lj18 and Kj6, respectively. The fluxes of CO2 and CH4 from the three varieties had positive correlations with air and soil temperature. The three kinds of rice fields were all sources of CO2, CH4, N20 （14.6- 23.3 t·hm^-2·a^-1, 345.1-737.8 kg·hm^-2·a^-1, 0. 148-0. 227 kg·hm^-2·a^-1 respectively） in growing season. The three rice fields contributed CO2 26.9-32.7 t·hm^-2·a^-1 to the global warming potential （ GWP）, and GWP were mainly composed of CO2 and CH4 emissions.