大兴安岭干旱阳坡各类退化类型土壤微生物特征研究

Soil Microbiological Characteristics of Various Degenerative Types of Drought Sunny Slope in Daxing'anling Forest Region

通过对干旱阳坡蒙古栎林、灌丛、草丛等3种群落类型的微生物群落功能多样性分析,结果表明:3种不同退化阶段的根际土微生物碳代谢活性差异均达显著水平。其中,灌草丛根际土微生物碳代谢强度最强;蒙古栎林根际土次之;而草丛的根际土微生物代谢强度最低,土壤微生物碳代谢活性最弱。三者之间均匀度指数差异不明显,说明土壤微生物均匀度未随植被的退化而发生改变。灌丛和蒙古栎林土壤微生物的碳利用模式相近。灌丛及蒙古栎林土壤微生物对31种碳源代谢能力大于草丛,差异显著。

The functional diversity of microbial communities in three communities（Quercus mongolicaforest,shrub and grass community）on the dry sunny slope was analyzed.Result shows that the difference of microbial carbon metabolic activity in three rhizosphere soils is significant at different degradation stages;rhizosphere soil have the strongest microbial carbon metabolism,while rhizosphere soil of Quercus mongolicaforest is the second;the microorganism of rhizosphere soil in grass is the lowest,the activity of carbon metabolism of soil microorganism is the weakest.There is no significant difference in evenness index among the three,indicating that the soil microbial evenness did not change with the vegetation degradation.The carbon utilization patterns of soil microbes in shrub and Quercus mongolicaforest are similar.For shrub and Quercus mongolicaforest,their soil microbes on the metabolic ability of 31 carbon sources are higher than that of grasses,and the differences are significant.