黄河三角洲盐渍化农田不同轮作方式对土壤理化性质和小麦产量的影响

Effects of Different Crop Rotation Systems on Soil Chemical and Physical Characteristics and Wheat Yield in Salinity Croplands of the Yellow River Delta

本试验设置4种不同轮作方式(小麦-玉米、小麦-田菁、小麦+牛粪堆肥+5‰菌剂和小麦-玉米+改良剂)处理,研究其对黄河三角洲盐渍化农田土壤养分有效性和小麦产量的影响。结果表明,轮作措施显著影响盐渍化农田土壤理化性质和小麦产量。与其它轮作方式相比,玉米季牛粪堆肥处理能够显著提高表层土壤有机碳、有效磷和速效钾等养分含量,并提高土壤大颗粒团聚体分布比例,显著提高小麦产量;玉米季种植田菁能够有效提高根层土壤氮素有效性,对其它土壤养分有效性和小麦产量均无显著提升作用;小麦种植前施用改良剂对土壤养分有效性和小麦产量均无显著正效应。种植田菁和施用改良剂均不利于大颗粒团聚体的形成,不利于土壤理化性质的提升。综合来看,玉米季牛粪堆肥处理提高小麦产量和提升土壤理化性质效果最佳。本研究为两年试验数据,随试验年限延长,其效果可能会发生变化,因此盐渍化农田轮作方式对土壤理化性质和小麦产量的影响尚需进一步研究。

In order to research the effects of different crop rotation systems on soil nutrient availability and wheat yield in salinity croplands in the Yellow River Delta,4 rotation systems were set as wheat cultivated after maize,wheat cultivated after sesbania,wheat cultivated after cow compost with microbial inoculums and wheat cultivated after maize with ameliorant.The results showed that wheat yield and soil chemical and physical characteristics significantly changed in different rotation systems in salinity croplands.Compared with other rotation systems,wheat cultivated after cow compost with microbial inoculums could significantly increase wheat yield by improving the concentration of soil organic carbon,available phosphorus and available potassium in topsoil and increasing the ratio of large particles of soil aggregate.The nitrogen availability in root layer soil could be effectively improved with wheat cultivated after sesbania,but no significant improvement was found in other nutrient availability and wheat yield.Applying ameliorant before wheat cultivation had no significantly positive effect on soil nutrient availability and wheat yield.Planting sesbania and applying ameliorant were not benefit to the formation of large particles of soil aggregate and the improvement of soil chemical and physical characteristics.In a word,wheat cultivated after cow compost was the best in increasing wheat yield and improving soil chemical and physical characteristics.However,these results were concluded based on only 2-year data,and the effects would change with the increase of experiment years,so more researches would be necessary for exploring the effects of rotation systems on wheat yield and soil chemical and physical characteristics in salinity croplands.