Abstract: The effects of the legumes planted between apple tree lines on soil microbial population and soil enzyme activities were investigated. The quantities and proportions of total microorganism, bacteria, fungi and actinomyces as well as the activities of sucrase, urease and catalase in the 0~20 cm soils were analyzed. Results showed that the bacteria was dominant, accounting for more than 77% of the total microorganism, actinomyces followed and the fungi was least, accounting for 0.01%~0.04%. Compared with the control, the proportion of the actinomyces decreased, while that of the bacteria increased in the soil with covering legumes. The fluctuation was 1.2%~4.4% in 0~10 cm soil, but 18% in 10~20 cm. The effect enhanced as soil depth increased. The quantity of actinomyces decreased while the quantity of fungi, sucrase and urease activities increased in the legume-covered soil. Effect varied in different plant species and soil depths, however, the legumes had no significant effect on the catalase activity. Specifically, total microorganisms and bacteria decreased in the 0~10 cm soil covered with Lotus cornioulatus and Trifolium repens while they increased in the 10~20 cm soil covered with T. pretense. Sucrase activities increased in the 0~10 cm soil and urease activities increased in the 0~20 cm soil covered with L. cornioulatus, whereas sucraseactivities increased in the 0~20 cm soil and urease activities increased in the 10~20 cm soil covered with T. repens and T. pretense. In conclusion, the legume covering could change the microorganism population and the enzyme activity of the apple orchard soil, dependent on the legume species and the soil depths.

Key words: Apple orchard, Legume, Soil, Microorganism, Enzyme activity

摘要： 为明确苹果(Malus pumila)树行间种植不同豆科牧草后对园中土壤微生物区系和土壤酶活性的影响,于苹果园建植第1年,在果树行间种植百脉根(Lotus cornioulatus)、白三叶(Trifolium repens)和红三叶(T. pretense),以果树行间"清耕"土壤为对照,研究0~20 cm土层中微生物总数、细菌、真菌、放线菌的数量及其比例和蔗糖酶、脲酶、过氧化氢酶活性的变化规律。结果表明:园中土壤微生物区系中,细菌占土壤微生物总数的77%以上,放线菌次之,真菌最少,为0.01%~0.04%;种草后,土壤中放线菌比例减少,细菌增加,此趋势随土壤深度增加而加剧,0~10 cm土层中增减比例幅度为1.2%~4.4%,而10~20 cm土层中为18%。种草后,放线菌数量减少,真菌数量、蔗糖酶及脲酶活性增加,增减幅度因草种及土壤深度而异,而对过氧化氢酶活性无影响。在种植百脉根、白三叶的0~10 cm土层中微生物总数、细菌数量减少,而种植红三叶的10~20 cm土层中微生物总数、细菌数量增加;种植百脉根后,0~10 cm蔗糖酶活性、0~20 cm脲酶活性升高,种植白三叶、红三叶后,0~20 cm土壤蔗糖酶、10~20 cm土壤脲酶活性升高。说明种草可改变苹果园土壤微生物区系和酶活性,此作用和草种、土壤深度密切相关。

关键词: 苹果园, 豆科牧草, 土壤, 微生物, 酶活性