摘要
为提高华北平原冬小麦种植体系的氮肥利用率、减少氮肥对环境的污染,本研究对前人的试验数据进行整理核算,分析肥料氮、作物氮和土壤氮三者之间的关系,探索冬小麦季化肥氮的去向及土壤氮库的盈亏情况。结果表明：华北平原冬小麦当季化肥氮的吸收量随施氮量的增加而升高,对土壤氮素的吸收随施氮量的增加而降低;在秸秆50%还田和100%还田两种情况下,土壤氮库盈亏量与施氮量之间均呈线性极显著正相关,且土壤氮库达到平衡时的施氮量分别是N 192和166kg·hm-2;冬小麦对氮肥的吸收利用率推荐施氮远高于传统施氮,过量施氮不仅不会提高作物产量,还会降低氮肥利用率,增加土壤残留和损失;3种秸秆处理方式下的冬小麦氮肥各去向绝对量与施氮量（N 75-375 kg·hm-2）之间均呈显著线性相关关系,秸秆不还田条件下的地上部吸收率、秸秆吸收率和秸秆50%还田下的地上部吸收率及秸秆100%还田下的0-100 cm土壤残留率均与施氮量（N 75-375 kg·hm-2）之间呈显著相关关系。
In order to increase utilization efficiency of nitrogen fertilizer in planting system of winter wheat in North China plain and decrease the environmental pollution from fertilizer nitrogen, the original date were collected from the previous studies of 15N-microplot experiments to investigate the relationships of fertilizer nitrogen, crop nitrogen and soil nitrogen, and explore the fate of fertilizer nitrogen in winter wheat cropping system and budget of soil nitrogen pool. The results iUstrated thatthe N uptake by wheat plants from fertilizer nitrogen increased with the increase of N fertilizer application rates, while the N uptake from soil nitrogen showed the opposite trend; There were the significantly positive linear correlations between nitrogen application rates and balance of soil N in the two conditions of 50% and 100% straw returning to field. When nitrogen fertilizer rates were N 192 kg·hm-2 and N 166 kg·hm-2 at these two situation, the soil nitrogen pool reached the balance; The N utilization efficiency when nitrogen rate recommended is much higher than that when the traditional nitrogen rate applied in soil with winter wheat. Excessive application of N fertilizer not only improved crop yields but also reduced the nitrogen utilization efficiency and increased N loss and N accumulation in soil. In the conditions of 0%, 50% and 100% straw returning to field, there were the significant linear relations between the amounts of different N fates and nitrogen application rates （N 75-375 kg·hm-2） under the three application above. A significant correction relation was showed between total nitrogen recovery rate as well as straw use rate of 0% straw returning to field and nitrogen application rates （N 75-375 kg·hm-2） between, total nitrogen recovery rate of 50% straw returning to field and nitrogen application rates （N 75-375 kg·hm-2） between, 0-100cm soil residual rate of 100% straw returning to field and nitrogen application rates （N 75-375 kg·hm-2） within a certain range.
出处
《生态环境学报》
CSCD
北大核心
2013年第3期392-397,共6页
Ecology and Environmental Sciences
基金
国家"十二五"粮食丰产科技工程资助(2011BAD16B08S03)
关键词
15N
华北平原
冬小麦
氮去向
化肥
土壤氮库
施氮量
15N
north China plain
winter wheat
fate of nitrogen
fertilizer
soil nitrogen pool budget
nitrogen application rates
