柽柳冠茎对其土壤酶活性及微生物数量的影响

为了研究土壤酶活性和微生物数量空间变化规律,在塔里木河中游以柽柳为建群种的群落中,选取3种不同大小冠幅的柽柳灌丛类型,按根部、灌丛下和冠幅边缘分别采集0~20 cm土样,测定土壤脱氢酶、多酚氧化酶、脲酶、过氧化氢酶、转化酶、碱性磷酸酶6种酶活性和细菌、真菌、放线菌数量。结果表明,无论柽柳灌丛冠幅大小,从根部、冠幅下到冠幅边缘,土壤中6种酶活性及微生物数量均依次表现为由高到低的变化规律;随着柽柳冠幅的增大,在相同取样部位,6种酶活性及土壤微生物数量均相应增加;土壤中6种酶的活性与细菌、真菌、放线菌数量均呈现正相关性。

The Effect of Tamarix spp Canopy on the Soil Enzyme Activities and the Microbial Quantity

Studying on the spatial variation regulation of soil enzyme activities and the microbial quantity under canopy of Tamarix spp.shrubs,the Tamarix spp shrubs of the different canopy type in middle reaches of Tarim river were chosen.From rhizosphere,under the canopy of Tamarix spp to edge of shrubs,the soil(0~20 cm)was collected and was used to measure dehydrogenases,polyphenol oxidase,urease,catalase,invertase and alkalescence phosphatases of soil enzyme activities and the quantity of bacteria,actinomyces and fungi.The results showed that six kinds of soil enzyme activities and three kinds of the microbial quantity both increasing from rhizosphere,under the canopy of Tamarix spp.to edge of shrubs,whatever the canopy of Tamarix spp.shrubs are small or large.At the same soil sampling position,the six kinds of soil enzyme activities and three kinds of the microbial quantity are both increasing when the canopy of Tamarix spp.shrubs enlarge.The correlation is very prominent between six kinds of soil enzyme activities and three kinds of the soil microbial quantity.