摘要
对氮肥和稻草氮的利用率进行了3年6季同位素15N田间定位研究。结果表明,首季单季水稻对氮肥的利用率为37.02%,050cm土壤中15N的残留率为25.81%。经过连续3年6季的种植,作物肥料N的累计回收率分别为40.15(秸杆还田)41.63%(秸杆不还田),050cm土壤中15N的残留率仍达到23.62(秸杆不还田)28.33%(秸杆还田)。在不施氮肥条件下,小麦对稻草氮的吸收率为4.46%,第二季单季稻对稻草氮的吸收率为4.78%。5季作物累计吸收稻草氮11.76%,而土壤残留率为70.37%。
A three-years,experiment for nitrogen recovery of chemical fertilizer and rice straw by isotope ^(15)N was conducted under field condition. The results showed that ^(15)N recovery in the first crop of single late-rice was 37.02%,the ^(15)N residue rates was 25.81% in 0~50cm soil.The ^(15)N recovery in second season crop of winter wheat was 1.55% for treatment with straw return and 2.08% for that no return,respectively. The accumulated ^(15)N recovery in continuous six season crops was 40.15% for the plot straw return to soil and 41.63% for that in no return,respectively. The ^(15)N residue rate in 0-50cm soil at the end of sixth crop was 23.62% and 28.33%. When ^(15)N -labeled rice straw was applied as N source, the recovery of ^(15)N in the first season crop of wheat was just 4.46%,and that in second season crop of single late-rice was 4.78%. The accumulated ^(15)N recovery in the continuous five season crops was 11.76%. The ^(15)N residue rate in 0-50cm soil at the end of the fifth crop was (70.37%.)
出处
《土壤通报》
CAS
CSCD
北大核心
2004年第6期763-766,共4页
Chinese Journal of Soil Science
基金
联合国FAO/IAEA"持续农业与环境保护下土壤有机质管理与养分循环"(编号:CRP-8896)项目资助
关键词
肥料
稻草
氮肥回收率
氮素
同位素
Nitrogen
Rice straw
^(15)N trace
Fertilizer recovery
