摘要
采用室内模拟覆盖和好气培养的方式,测定不同培养时间土壤中硝态氮和铵态氮的含量,研究不同土壤条件下稻草覆盖对红壤氮素矿化的影响。在不同水分和不同施氮条件下,20和30℃时稻草覆盖均使土壤中氮素净矿化量减少;40℃时短期覆盖使土壤中氮素净矿化量低于不覆盖,长期覆盖后土壤中氮素净矿化量大于不覆盖。随着温度的升高,覆盖处理氮素净矿化量与不覆盖差异减小甚至消失。土壤含水量升高,覆盖处理土壤中氮素净矿化量较不覆盖更低。结果表明:稻草覆盖减少了土壤中无机态氮含量,减缓了土壤有机态氮向无机态氮的转化速率,从而减少了水土流失造成的养分损失,但在作物生长旺盛期,稻草覆盖应与氮肥配合使用,以满足作物需求。
The effects of straw mulching on red soil N mineralization at different temperature,soil moisture,N fertilization were investigated through laboratory aerobic incubation.The results showed that if the soil was mulched by straw,its net N mineralization was lower than that of the non-mulched soil during the incubation time at 20,30 ℃.At 40 ℃ the net N mineralization of soil in mulching was lower than that of non-mulching during the first 40-day but higher than that of non-mulching after incubating 60 days.When the soil moisture was at 0.20 cm3/cm3 or 0.25 cm3/cm3,the difference between the mulching and non-mulching was more remarkable than that at 0.15 cm3/cm3.When the temperature was raised,the difference was narrowed and even disappeared.The straw mulching also had effects on soil N nitrification and N ammonification.When the temperature was 20 ℃ and soil moisture was 0.15 cm3/cm3,N nitrification was lower and N ammonification was higher in the mulching treatment.When the temperature was 40 ℃ and soil moisture was 0.25 cm3/cm3,N nitrification was higher and N ammonification was lower in mulching treatment than that of non-mulching treatment.These results suggest that it is essential to adjust the application of straw mulching in red soil fields according to the soil moisture and N fertility.
出处
《华中农业大学学报》
CAS
CSCD
北大核心
2011年第6期717-721,共5页
Journal of Huazhong Agricultural University
基金
国家自然科学基金项目(40871139)
国家"十一五"科技支撑计划项目(2009BADC6B01)
