不同海拔表层土壤微生物数量消长的机理

The Changing Mechanisms of Microbial Number on Surface Soil with Altitude

以乌鲁木齐河源区不同海拔表层土壤样品为研究材料,利用荧光显微计数技术、寡营养恢复培养技术等,研究了微生物的数量与土壤理化参数和植被类型的关联度.结果表明:表层土壤中可培养细菌数与表土含水量、总C、总N和pH值相关性不显著,与相应的植被类型明显相关,可培养细菌数从大到小所对应的植被为:苔草>嵩草>芨芨草>针阔叶混交林>云杉>车前草>山莓草;在相同植被类型下,可培养细菌数量表现出随海拔升高而降低的趋势.植被类型是影响土壤可培养细菌数量的主要因素,但海拔变化对可培养细菌数量的影响也不可忽略.

Surface soil were sampled from different altitude and then sent to study the relationship among the microbial abundance,the soil physicochemical parameters and the vegetation types by using the fluorescence microscope enumeration method and oligo-culture method.It was found that the abundance of cultivable bacteria was correlated insignificantly with soil moisture,total carbon and total nitrogen concentrations,and pH value.However,it was significantly correlated with vegetation types,and the abundance of cultivable bacteria followed the order：CarexKobresiaAchnatherummixed coniferous broad leaved forestPiceaPlantagoSibbaldia.The abundance of cultivable bacteria was also correlated negatively with altitude for the same vegetation type.All the results suggested that the vegetation type was the principal factor that controlled the abundance of soil cultivable bacteria,but the altitude effect can not be ignored.