摘要
为给双季稻水肥高效利用调控技术提供理论基础,设置间歇灌溉和淹水灌溉两种灌溉方式,高氮、中氮、低氮和不施氮这4种施肥方式,开展大田小区试验,探讨了水氮组合模式对双季稻CH4和N2O排放的影响.结果表明,间歇灌溉显著降低了CH4积累排放量,与淹水灌溉相比,早晚稻分别降低13.18~87.90 kg·hm-2和74.48~131.07 kg·hm-2,分别减排了24.4%~67.4%和42.5%~66.5%;但促进了N2O排放,早晚稻的增排量分别为0.03~0.24 kg·hm-2和0.35~1.53 kg·hm-2,分别比淹水灌溉增加6.2%~18.3%和40.2%~80.9%.总体上,间歇灌溉降低了稻田温室气体的增温潜势,其中早稻降低了18.8%~58.6%,晚稻降低34.4%~60.1%,两季综合降低2 388~4 151 kg·hm-2(以CO2eq计),下降41%~54%.通过相关分析发现,土壤CH4排放和土壤溶液Eh显著负相关,和溶液CH4浓度显著正相关.与淹水灌溉相比间歇灌溉模式有利于减排CH4,虽增排了N2O,但增温潜势显著减少.综合来看,间歇灌溉配施中氮更有利于双季稻种植.
To provide support for the efficient use of water and fertilizer technology to double-season rice cultivation,water and fertilizer coupling mode was applied in this research,including two irrigation methods and four N levels. The irrigation methods were flood irrigation and intermittent irrigation,while four N levels were high-N,middle-N,low-N and none-N. Field experiment was conducted to study the effect of water and fertilizer coupling mode on CH4 and N2O emission. The results showed that the accumulated CH4 emissions were significantly reduced by intermittent irrigation,in comparison with flood irrigation,the reduction in early rice season were from 13. 18 kg·hm- 2to 87. 90 kg·hm- 2,and were from 74. 48 kg·hm- 2to 131. 07 kg·hm- 2in late rice season,with a rate of24. 4%-67. 4% and 42. 5%-65. 5% respectively; whereas the accumulated N2 O emissions were increased,the increment were from0. 03 kg·hm- 2to 0. 24 kg·hm- 2in early rice season and from 0. 35 kg·hm- 2to 1. 53 kg·hm- 2in late rice season when compared flood irrigation,increased by 6. 2%-18. 3% and 40. 2%-80. 9% respectively. On the whole,intermittent irrigation reduces the warming potential of greenhouse gases( GWP),which were decreased by 18. 8% to 58. 6% in early rice season and by 34. 4% to60. 1% in late rice season,and the reduction of total GWP were from 2 388 to 4 151 kg·hm- 2( CO2eq),with a rate of 41%-54%.Through correlation analysis it found that CH4 emissions from soil were significantly related with soil solution Eh and solution CH4 concentration. In comparison with the flood irrigation,the application of intermittent irrigation in double-season rice cultivation was conducive to CH4 reduction, though the increase came in N2 O, but the GWPs were significantly reduced. Comprehensively,intermittent irrigation matching with middle-N is more benefit to double-season rice cultivation.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2015年第9期3365-3372,共8页
Environmental Science
基金
国家科技支撑计划项目(2013BAD11B02
2011BAD16B01
2012BAD04B10
2013BAD07B11)
湖南省科技厅支撑计划项目(2013SK3158)
关键词
双季稻
间歇灌溉
CH4
N2O
减排
double-season rice
intermittent irrigation
CH4
N2O
emission reduction
