秸秆还田配施化肥对春玉米耕层土壤理化性质及产量的影响

通过连续3 a田间定位试验，研究了不同秸秆还田方式配施化肥对春玉米耕层土壤理化性质及产量的影响。结果表明：秸秆还田能显著提高各土层的田间持水量8.6%～18.0%，降低土壤紧实度6.3%～27.5%，且以秸秆深翻和深旋还田方式效果较好，同时这两种方式还能显著降低20～40 cm土层容重。连续秸秆还田后耕层土壤有机质、碱解氮、有效磷和速效钾含量较无还田处理平均提高21.2%、8.6%、15.0%和17.2%。此外，在秸秆还田时配合适量氮肥施用更利于土壤养分的提高，其中秸秆深翻和秸秆深旋配施210 kg/hm2氮肥和90～120 kg/hm2钾肥可显著提升土壤养分状况，促进春玉米穗长、穗粗和百粒重的增加，进而提高春玉米产量，是辽宁棕壤区春玉米生产中比较理想的一种农艺措施，在农业发展中具有一定的应用和推广价值。

Effects of Straw Incorporation Combined with Fertilizer on Physiochemical Properties of Soil and Yield of Spring Maize

A 3-year located field experiment was conducted to study the influences of different straw incorporation methods combined with fertilizers on physiochemical properties of soil and yield of spring maize. The results show that no matter under what kind of straw returning methods, compared with non-straw returning, straw incorporation significantly increases the field capacity of every soil layer by 8.6%-18.0%, reduces soil compactness by 6.3%-27.5%, and deep turning and deep rotation of straws is better in the effects, which also significantly reduces soil bulk density of 20-40 cm. Straw incorporation increases the contents of soil organic matter by 21.2%, alkaline nitrogen by 8.6%, available phosphorus by 15.0% and available potassium by 17.2% in the plough layer after continuous straw returning for 3 years compared with the non-straw returning. In addition, appropriate nitrogen fertilizer combined with straw returning is more conducive to the improvement of soil nutrients. The application of 210 kg/hm² nitrogen and 90-120 kg/hm² potassium fertilizer with straw deep turning and rotation significantly improves soil nutrients, promotes the ear length and diameter as well as 100-grain weight, so increases the yield of spring maize, thus, it is an ideal model in spring maize production and has good application and promotion potential in agricultural development in brown soil area in Liaoning.