关键词: 科尔沁沙地, 固沙造林地, 微生物区系

Abstract: The studies conducted in afforested sand dunes of southwestern Horqin sandy land showde that the microbial population such as bacteria,actinomycst and fungi as well as their physiological groups in afforested sand dunes are more than in shifting sand dunes,and varied greatly with the forest ages and species.Their populations are higher in the old afforested sand dunes than in the new ones.Their amounts are more in upper layers of afforested sand dunes than in the subsoil layers.