稻草还田与施氮水平对土壤氮素供应和水稻产量的影响  

Impact of Rice Straw Incorporation and N Rates on Soil Nitrogen Supply and Rice Yield

作　　者：佘冬立[1] 王凯荣[1] 谢小立[1] 彭英湘[1] 陈敏[2] 

机构地区：[1]中国科学院亚热带农业生态研究所 [2]湖南省桃江县农业局,湖南桃江413400

出　　处：《土壤通报》2007年第2期296-300,共5页Chinese Journal of Soil Science

基　　金：国家"863"计划资助项目(2001AA264021);辽宁省"十五"重大攻关项目(2001208002)资助

摘　　要：比较研究了3年定位试验后稻草还田和施N水平对红壤双季稻作系统土壤供N能力、水稻吸N特征和水稻生产的影响。结果表明：头年晚稻草秋季还田对来年早稻土壤NH4^＋-N和作物吸N量的提高具有促进作用，而早稻新鲜稻草还田使晚稻土壤NH4^＋-N和作物吸N量均略低于移走稻草处理。稻草还田处理3年后，土壤可矿化N与移走稻草处理相比提高了35．4％～53．9％，且水稻各生育期干物质生产量均高于移走稻草处理，稻谷增产率达4．0％～4．7％。施用N肥可以显著增加土壤NH4^＋-N和可矿化N含量，且随着N肥用量的增加，水稻植株的累积吸N量和系统生产力（地上干物质量和产量）均显著的增加，建议N（全年施N量185kg hm^-2）和习惯N（全年施N量265kg hm^-2）处理相对于无N处理的增产率分别为35．2％和45．3％，而N肥的吸收利用效率分别为27％和25％，农学产量效益分别为每公斤纯N增产谷粒12．7kg和11．4kg。A field study was conducted to investigate the effects of three year - rice straw incorporation and N rates on rice yield, nitrogen absorption by the crops at the different growths stages and nitrogen supplying capacity of soils in the double rice cropping systems. The results showed that the impacts of rice straw incorporation on soil NH4^＋ - N and nitrogen absorption by the crops were different in different seasons. At the early rice season, rice straw incorporation in the last autumn increased soil NH4^＋ -N and nitrogen absorption by the crops, while the effect was negative in the latter rice season with the fresh flee straw incorporated immediately after early rice maturing. After three years of straw incorporation treatment, the soil mineralisable N was increased by 35.4 % - 53.9 %, and the dry matter weight of aboveground at all growth stages and grain yield were higher than those in the treatment of rice straw removing, and the rate of increase in grain yield was 4.0 % -4.7 %. The soil NH4^＋ -N, mineralisable N, rice yield and the nitrogen absorpdon by the crops were significantly increased when received N, and the rate of increase in grain yield was 35.2 % and 45.3 %, but the N recovery rate was 27 % and 25 %, and the agronomic efficiency was 12.7 and 11.4 kg grain/kg N respectively under the treatments of the recommended N and farmer＇s N.

关 键 词：稻草还田 施N水平 铵态N 可矿化N 吸N量 生产力 

分 类 号：S158[农业科学—土壤学]