玉米秸秆直接还田配施促腐剂效应研究 Ⅰ.对土壤氮素时空动态变化和作物产量的影响

THE EFFECT OF MAIZE STALK APPLICATION IN THE FIELD WITH TRANSFORMATION PROMOTER Ⅰ.ON THE SPACE-TIME DYNAMIC VARIATION OF SOIL N NUTRIENT AND WINTER WHEAT-CORN YIELDS

通过2年田间定位试验,研究了冀东地区玉米秸秆连续直接还田对土壤氮素养分时空动态变化和作物产量的影响。结果表明,玉米秸秆直接还田可明显提高土壤氮素供应水平,增产作用显著。在秸秆C/N15∶1～35∶1范围内,调节秸秆不同C/N未改变秸秆还田后的转化进程,其转化对土壤氮素时空动态变化的影响亦无明显差异,增产幅度大致相当。在调节秸杆C/N的前提下配施促腐剂,使秸秆还田后的转化进程明显加快,与秸秆直接还田未配施促腐剂处理比较,可有效提高土壤供氮能力,显著增加作物产量。调节玉米秸秆C/N为35∶1并配施促腐剂是冀东地区小麦—玉米一年两熟种植制度下,玉米秸秆直接还田较好的施肥方式。

A two-year field-orientation experiment conducted in the eastern part of HeBei Province about the effects on the space-time dynamic change of soil N nutrient and winter wheat-corn yields by applying maize stalk directly in the field showed that application of maize stalk in the filed could improve the N nutrient supply of soil and remarkably raised crop yield.By adjusting the proportion of stalk C/N from 15∶1 to35∶1, the course of transformation after application of maize stalk did not change.There was no remarkable difference for the space-time dynamic variation of soil N and crop yields.Comparatively, application of maize stalk after adjusting the proportion of straw C/N with transformation promoter not only remarkably quickened the step of transformation and improved the N supply of soil, but also remarkably raised crop yields. To sum up, adjusting the proportion of stalk C/N to 35∶1 combined with transformation promoter was the effective way to improve the N supply of soil and increase crop yields.