ABSTRACT

A three-year field experiment was conducted to evaluate the effects of straw combined with potassium fertilizer on maize yield, potassium utilization efficiency and soil potassium balance. The study consisted of two straw treatments (S1: straw returning; S0: no straw returning) and five K levels (0,30,60,90,120 kg K ha⁻¹). The results showed that compared to S0, the maize yield and available K content in S1 increased by 2.9%~6.2% and 19.3%~37.4%. The average of agronomy efficiency and surplus rate in S1 were 7.3%~35.4% and 24.8%~84.7% higher than S0 respectively, but the recovery efficiency, partial factor productivity under S0 and S1 were statistically identical. When the surplus rate is 0, the amount of potassium fertilizer required and the corresponding yield to maintain the soil K balance in S1 were 87.9 kg ha⁻¹ and 12,424.6 kg ha⁻¹. Compared to S0, S1 can decrease potassium fertilizer application rate by 10.2% while increasing maize yield by 3.5%. Overall, straw return combined with potassium fertilizer can improve maize yield and soil available potassium content, it can also reduce chemical fertilizer input while increasing fertilizer utilization efficiency, and play a positive role in keeping soil K balance simultaneously.

摘要

通过为期三年的田间试验，评价秸秆与钾肥配施对玉米产量、钾利用效率和土壤钾平衡的影响。该研究包括两种秸秆处理（S1：秸秆还田；S0：没有秸秆还田）和五个 K 水平（0,30,60,90,120 kg K ha ^-1）。结果表明，与S0相比，S1的玉米产量和速效钾含量分别提高了2.9%~6.2%和19.3%~37.4%。S1平均农艺效率和剩余率分别比S0高7.3%~35.4%和24.8%~84.7%，但S0和S1下的采收率、部分要素生产力在统计学上一致。当剩余率为 0 时，在 S1 中维持土壤钾平衡所需的钾肥量和相应的产量分别为 87.9 kg ha ^-1和 12,424.6 kg ha ^-1. 与S0相比，S1可使钾肥施用量降低10.2%，玉米增产3.5%。总体而言，秸秆还田配合钾肥可以提高玉米产量和土壤速效钾含量，在提高肥料利用效率的同时减少化肥投入，同时对保持土壤钾平衡起到积极作用。