摘要
采用静态箱-气相色谱法观测了常规栽培和水稻覆膜节水综合高产技术下川中丘陵地区稻田的CH4排放通量,探究覆膜节水综合高产技术对稻田CH4排放的影响。结果表明:整个水稻生长期,常规栽培与水稻覆膜节水综合高产技术稻田CH4排放总量分别为(35.0±3.5)和(5.1±1.0)g.m-2,后者较前者减少稻田CH4季节排放量的(86±4)%。二者CH4平均排放通量在不同水稻生长时期存在如下关系:孕穗期>抽穗期>成熟期>分蘖期。水稻各生长时期,覆膜节水综合高产技术均降低稻田CH4排放,在稻田CH4排放盛期(孕穗期)降幅达79%。在不同土壤水分状况下,水稻覆膜节水综合高产技术稻田CH4平均排放通量存在如下关系:烤田期>烤田后>烤田前;而常规栽培则为烤田期>烤田前>烤田后。不同于常规栽培,烤田对水稻覆膜节水综合高产技术下稻田CH4排放无明显影响,烤田后降雨促进其CH4排放。土壤水分状况由低变高更易促使覆膜节水综合高产技术下稻田CH4排放。覆膜节水综合高产技术栽培全生育期内,厢面CH4排放通量与土温、土壤Eh无显著相关性(P>0.05)。厢沟CH4排放与土温显著正相关(r=0.447*,P<0.05)。水稻移栽至烤田前,厢面CH4排放通量与土壤Eh显著负相关(r=0.624*,P<0.05)。
A field experiment using the method of static chamber-gas chromatogram was conducted to study CH4 emissions in paddy fields using the conventional rice cultivation technology and a new high yield rice planting technique integrated with plastic mulching for water saving, separately, during the rice growing season in the hill region of Central Sichuan. Results show that the during the rice growing season, the total CH4 emission was （35.0±3.5） g·m2 in the conventional field and （5.1±1.0） g-m2 in the field using the new technique and obviously, the latter was （86±4）% lower than the former. The average CH4 emissions of the two cultivation systems varied from growth stage to growth stage, but both followed the order of earring stage 〉 heading stage 〉 maturing stage 〉 tillering stage. The new technique decreased CH4 emission at all the rice growth stages, especially at the earring stage, and when CH4 emission was the highest, it did by as much as 79%. The effect of the new technique also varied with the soil water regime and the mean CH4 emission displayed an order of mid-season aeration 〉 post-aeration 〉 pre-aeration, while in the conventional field, it followed the order of mid-season aeration 〉 pre-aeration 〉 post-aeration. Different from the situation in the conventional field, the mid-season aeration did not have much effect on CH4 emission in the field using the new planting technique. In that field, rainfall after the mid-season aeration stimulated CH4 emission, and change in soil mois^re from low to high increased the emission, too. During the rice growing season, CH4 emission from the ridge had no significant correlation with soil Eh or soil temperature in the field using the new technique, whereas CH4 emission flux from the ditch did with soil temperature （r=0.447＊, P〈0.05）. During the period from transplanting to mid-season aeration, CH4 flux from the ridge was negatively related to soil Eh （r=0.624＊, P〈0.05）.
出处
《生态环境学报》
CSCD
北大核心
2013年第6期935-941,共7页
Ecology and Environmental Sciences
基金
中国科学院战略性先导科技专项(XDA05020200)
科技部国际科技合作项目(S2012GR0080)
国家自然科学基金项目(41071169)
公益性行业(农业)科研专项(201103039)
关键词
地膜覆盖
CH4排放
稻田
减排措施
烤田
plastic mulching
CH4 emission
rice field
mitigation option
aeration
