间作对根际土壤微生物和酶活性的影响研究

通过根箱试验,研究了玉米间作蚕豆和玉米间作鹰咀豆对根际土壤微生物和酶活性的影响.结果表明,玉米出苗60 d时,玉米、蚕豆复合群体中的玉米地上生物产量高于单作38%,增产显著;与鹰咀豆间作的玉米地上生物产量高于单作4%,差异不显著,间作蚕豆和鹰咀豆地上生物产量较单作显著降低.与单作玉米相比,玉米鹰咀豆间作后根际土壤脲酶和酸性磷酸酶活性显著降低,玉米间作蚕豆根际土壤酶活性与单作差异不显著;玉米鹰咀豆间作对细菌产生的根际效应显著高于玉米间作蚕豆,对真菌产生的根际效应与细菌相反.间作对放线菌、微生物总数产生的根际效应显著高于单作,间作根际微生物多样性指数显著高于单作.土壤微生物中细菌数量和微生物多样性指数是影响土壤酶活性的主要因子,间作根际土壤微生物多样性指数大于单作是弱化土壤酶活性的重要原因.

Effect of intercropping on soil microbial and enzyme activity in the rhizosphere

A root box experiment was carried out in order to research the effects of several different cereal-legume intercropping sequences on soil microbial and enzyme activity in the rhizosphere.60 days after Z.mays germination it was shown that the above ground biomass of Z.mays in Z.mays V.sativa intercropping system was enhanced by 38% compared with Z.mays grown in a monoculture,with the biomass of Z.mays in the Z.mays C.arieinum intercropping improved by 4%.In contrast,intercropping decreased the productivity of both V.sativa and C.arieinum significantly compared to the control.Compared to the Z.mays monoculture,the activity of urease and acid phosphates in the rhizosphere of the Z.mays C.arieinum intercropping was significantly decreased,with a non-significant difference between the Z.mays monoculture and the Z.mays V.sativa intercropping treatment.The effect in the rhizosphere of Z.mays C.arieinum intercropping on bacterial activity was significantly higher than that of Z.mays V.sativa intercropping,with the effect on fungi contrary.Intercropping significantly enhanced the effect of actinomyces in the rhizosphere and the total microbial number compared to monoculture cropping,with microbial diversity in the rhizosphere of intercropping systems significantly higher than that in monoculture cropping systems.The bacterial number and microbial diversity were the main factors influencing soil enzyme activity;the higher soil microbial diversity found in the rhizosphere of the intercropping systems was the main reason for improved soil enzyme activity.