白三叶返园对苹果园土壤微生物群落的影响

为了解苹果(Malus pumila)园中覆盖和埋置白三叶(Trifolium repens)对土壤微生物群落的影响,采用尼龙袋法将新鲜的白三叶覆盖和埋置到苹果园中,分别在白三叶降解1、3、6个月时,利用Biolog微平板法检测土壤微生物群落的功能多样性。结果表明,覆盖和埋置白三叶均可使苹果园土壤微生物代谢活性显著提高(P0.05),微生物的多样性除6个月外显著增加、丰富度显著增加,均匀度显著降低(P0.05),群落结构发生变化,且覆草处理大于埋草,同时,白三叶降解时间的长短也影响土壤微生物群落。土壤微生物群落主成分分析结果显示,不同返园方式间主要对羧酸类碳源的利用有差异,而导致不同降解时间土壤微生物群落代谢差异的主要是糖类。说明在苹果园覆盖和埋置白三叶可改变土壤微生物群落,而覆盖白三叶对微生物群落结构的改善情况显著优于埋置白三叶。

Influences of white clover returning to apple orchard on soil microbial community

In order to understand the effects of burying and covering white clover (Trifolium repens )in apple (Malus pumila )orchard on the soil microbial community,the soil microbial community functional diversity was analyzed by Biolog microplate method after 1,3 and 6 months treatments which fresh white clover was buried or covered in apple orchard by litter nylon bag,respectively.The results indicated that both covering and burying white clover could significantly elevate (P ﹤0.05)the soil microbial metabolism activities,the microbi-al Shannon-Winner diversity index(except 6 months)and richness index while significantly reduced (P ﹤0.05) uniformity index and changed soil microbial community structure.The effects of covering white clover were greater than that of burying.And the time of white clover degradation also had effects on soil microbial commu-nity.Principal component analysis of soil microbial community showed that the major differences between cov-ering and burying were the utilization of carboxylic acids,whereas the major differences of microbial metabo-lism activities between degradation periods were sugars.These results indicated that both covering and burying white clover can change the soil microbial community in apple orchards,and the effects of covering were greater than that of burying.