北方粳稻最优产量氮肥阈值周年变化及其影响因素分析

Annual Variation of Nitrogen Fertilizer Threshold for Optimal Yield of Northern Japonica Rice and Its Influencing Factors Analysis

为探讨水稻氮肥阈值周年间变化及其影响因素,科学制定化肥减施策略,通过8年的田间定位试验,利用线性加平台肥料效应函数分析水稻目标产量下的氮肥阈值周年变化及其影响因素。结果表明,试验区水稻目标产量为9860~10019kg/hm^(2),氮肥阈值为205.02~220.61kg/hm^(2),基于稻田氮素表观平衡的目标产量氮肥阈值周年变化最大幅度为7.60%,其直接影响因素表现为土壤无机氮含量>植株吸氮量>灌溉输入无机氮含量,间接影响因素是降雨携带无机氮含量。

In order to explore the interannual change of nitrogen fertilizer threshold for rice and its impact factors and provide a theoretical basis for the scientific development of fertilizer reduction strategy,based on eight years field positioning experiments,interannual changes and the impact factors were determined under the target yield of rice by fertilizer response linear plus plateau and quadratic model.The results showed that target yields and threshold nitrogen of rice were 9860-10019kg/ha and 205.02-220.61kg/ha.The maximum range of interannual change was 7.60%based on nitrogen surface balance in paddy field.The order of direct impact factors were inorganic nitrogen content>nitrogen acquisition of plant>input nitrogen through irrigation,and the indirect factor was nitrogen in precipitation.