葡萄园行间生草体系中土壤微生物数量的变化及其与土壤养分的关系

在酿酒葡萄生产园行间播种白三叶草、紫花苜蓿和高羊茅,以清耕为对照,研究了土壤微生物数量的变化及其与土壤养分的关系。结果表明,与清耕(对照)相比,行间生草总体使葡萄园土壤微生物数量增加,其中固氮菌与纤维素分解菌数量升高幅度较大,平均升高幅度分别为223.4%和83.4%,细菌数量平均升高68.1%,放线菌数量升高的幅度最小。白三叶草和紫花苜蓿处理较高羊茅处理增加的幅度大,除放线菌外,均与清耕之间差异达显著水平。行间生草使土壤有机质含量显著提高,全P、速效P含量降低;白三叶草和紫花苜蓿处理使土壤全N、碱解N、速效K含量显著提高,高羊茅处理使其降低。除速效P外,其余土壤养分与土壤微生物因子均呈显著或极显著正相关。通径分析表明,纤维素分解菌是影响土壤有机质最重要的微生物因子,放线菌是影响土壤N、P、K最重要的微生物因子。

Variation of Soil Microbial Populations and Relationships Between Microbial Factors and Soil Nutrients in Cover Cropping System of Vineyard

Three such cover crops，two perennial legumes (white clover and alfalfa) and a perennial gramineous grass（tall fescue）were sown inter-row in Cabernet sauvignon vineyard，with clean tillage as the control. The effects of cover cropping on microbial populations，soil nutrient contents and their relationships were studied. The results showed that soil microbial quantities in cover cropping treatments were increased，among which azotobacter and cellulose-decomposing and bacteria microorganisms increased by 223.4%，83.4% and 68.1%，respectively，but only slightly changing for actinomyces，compared with bare soil（control），the soil from white clover and alfalfa plots showed higher quantities of microbial populations than tall fescue polt，and significant differences were observed between the two cover crop treatments and the control（except actinomyces）. Also，it indicated that cover crop treatments had higher soil organic matter content，but reduced available P and total P. For white clover and alfalfa treatments，the contents of soil hydrolyzable N，total N，available K increased evidently，while decreased for tall fescue treatment. All kinds of soil nutrients showed significant or very significant position correlations with soil microorganism factors，except that soil available P were no significant correlations with fungi and azotobacter. Path analysis indicated that in the vineyard intercropping system，soil cellulose-decomposing microorganisms was the main factor affecting the accumulation of soil organic matter，soil actinomyces was the most important factor affecting soil total N，hydrolyzable N，total P，available P and available K.