不同施肥措施对春玉米农田土壤酶活性的影响

为研究肥料配比对春玉米农田土壤酶活性的影响,连续4年采用田间定位种植春玉米,分析各生育期各土层酶活性,利用聚类分析和主成分分析揭示酶活性的动态变化差异。结果表明,各种施肥措施显著增加蔗糖酶、脲酶和磷酸酶活性,主要影响10~20 cm土层酶活性。施用有机肥土壤酶活性最大值出现在散粉期,施用无机肥土壤酶活性最大值出现在大喇叭口期。随着土层深度的增加,蔗糖酶、脲酶、磷酸酶活性呈下降趋势;过氧化氢酶活性10~20 cm土层最低。配合施肥中增施氮肥降低过氧化氢酶活性,增加蔗糖酶、脲酶活性;增施磷肥增加脲酶、磷酸酶活性;增施有机肥增加过氧化氢酶活性,降低蔗糖酶、脲酶活性。单施氮肥降低土壤脲酶和磷酸酶活性。有机无机肥配施能够延长春玉米生育期土壤酶活性的高值期。土壤蔗糖酶、脲酶、过氧化氢酶和磷酸酶活性分别受全钾、全氮、有机质和全氮、全磷和有机质含量的影响,施肥通过改变土壤元素含量及供给能力影响土壤酶活性。

Effects of different fertilizer application on soil enzyme activity of spring corn

The effect of fertilizer combination on the soil enzyme activity was studied in spring maize farmland. The field loca-tion planted spring maize for 4 years. The soil enzyme activity was analyzed in the different growth period. The differences of dynamic changes of enzyme activity were revealed using the cluster discriminant analysis and the principal component analysis. The results showed that fertilization significantly increased the activities of sucrase, urease and phosphatase, and mainly affect-ed the enzyme activity of 10~20 cm soil layer. The soil enzyme activity reached the maximum in the powder period with organ-ic fertilizer application and in the big trumpet period with inorganic fertilizer application. With the increasing of soil depth, the activities of sucrase, urease and phosphatase decreased. Catalase activity reached the minimum in 10~20 cm soil layer. In various fertilization treatments, with the increasing of nitrogen content, the catalase enzyme activity decreased, and the su-crose and urease activity increased. The urease and phosphatase activity increased with more phosphate application. The cata-lase enzyme activity increased, and the sucrose and urease activity decreased when organic fertilizer was increased. While with only nitrogen fertilizer, urease and phosphatase activities reduced. Organic and inorganic combined fertilizers extended the high value duration of soil enzyme activity during the spring maize’s growth period. The activity of sucrase, urease, catalase and phosphatase was influenced respectively by total potassium, total nitrogen, organic matter and total nitrogen, total phosphorus and organic matter content. Fertilization affected soil enzyme activity by changing soil elements content and supply a-bility.