西北半干旱区葡萄园生草体系中土壤生物学特性与土壤养分的关系

Relationship Between Soil Biological Characteristics and Nutrient Content Under Intercropping System of Vineyard in Northwestern Semiarid Area

【目的】在葡萄园行间生草条件下研究土壤微生物数量、土壤酶活性与土壤养分的变化及其相关性,阐明土壤生物学指标与土壤肥力的关系。【方法】在酿酒葡萄园行间播种白三叶草、紫花苜蓿和高羊茅,以清耕为对照,测定土壤5种微生物数量、6种土壤酶活性及8个养分指标,分析其变化特征及相互关系。【结果】行间生草总体使土壤微生物数量和土壤酶活性提高,但高羊茅处理使脲酶和蔗糖酶活性降低;行间生草均使土壤有机质含量升高,白三叶草和紫花苜蓿处理使葡萄园土壤碱解N、全N、速效K含量升高,高羊茅处理使其降低,禾本科牧草高羊茅活化P的作用较大。相关分析表明,土壤有机质、全N、碱解N、全P、速效K与土壤细菌、真菌、放线菌、固氮菌、纤维素分解菌、脲酶、碱性磷酸酶、淀粉酶、蔗糖酶、纤维素酶均呈极显著或显著正相关;除过氧化氢酶外,土壤微生物数量与其余酶活性之间也存在极显著正相关关系。而过氧化氢酶与土壤养分和微生物相关性均不显著,全K与所有生物学特性指标无显著相关关系,土壤pH与土壤生物学特性指标呈负相关关系。【结论】行间生草可提高土壤微生物数量、酶活性及土壤肥力,豆科牧草紫花苜蓿和白三叶草提高的效应较明显;土壤生物学指标与土壤养分具有一定的相关性,土壤生物学指标可以反映葡萄园土壤质量的变化。

【Objective】 In this paper,the relationship between soil quality and soil biological characteristics such as soil microorganism quantity and soil enzymatic activity was studied in the intercropping system of vineyard,in order to illustrate the function of soil biological characteristics as bio-indicators of soil fertility.【Method】 Three such cover crops,two perennial legumes（white clover and alfalfa） and a perennial gramineous grass（tall fescue） were sown in vineyard.Soil microorganism quantity,soil enzymatic activities and soil nutrient content were analyzed and compared with that in soil cultivation.【Result】Most detected soil microorganism quantity and soil enzymatic activity,soil organic matter were increased under cover crop treatments,compared to clean tillage,tall fescue treatment decreased urease and sucrase activity.White clover and alfalfa treatments significantly increased the contents of hydrolyzable N,total N and available K,and tall fescue decreased them,while the activated organic P in tall fescue treatment was more effectively than that in white clover and alfalfa treatments.Correlation analysis indicated that soil organic matter,total N,hydrolyzable N,total P,available K showed significant or very significant positive correlation with 10 soil biological characteristic factors such as bacteria,fungi,actinomyces,azotobacter,cellulose-decomposing bacteria,urease,phosphatase,amylase,sucrase,and cellulose.The catalase activity was no significant correlation with all the soil nutrient contents,and the total K content was no significant correlations with all the soil biological characteristic factors.The soil pH in this experiment was negatively correlated with soil biological properties.【Conclusion】 Cover crops in the inter-rows of vineyard increased soil microorganism quantity,soil enzymatic activity and soil nutrient content,white clover and alfalfa treatments were better than tall fescue.There are significant correlations between soil biological characteristics and nutrients,and soil biological indexes could reflect the changes of soil quality.