Abstract: Aimed to understand the soil microbes functional diversity in sand-fixing Caragana microphylla communities in Horqin Sandy Land, the soil microbial carbon sources metabolism diversity in 9-, 16-, and 26-yr-old C. microphylla plantations, natural C. microphylla community, and moving sand dune was examined by the method of Biolog ECO-microplate culture. Within 264 h of culture, the average well color development (AWCD) and the capabilities of soil microbes in metabolizing carboxylic acids, carbohydrates, polymers, amino acids, amines, and aromatics were obviously higher in moving sand dune than in the plantations. The carbon source types metabolized by soil microbes increased with the increasing age of the plantations, and the carbon source metabolic pattern of the soil microbes in 26-yr-old C. microphylla plantation was similar to that in natural C. microphylla community. The functional diversity and evenness index of soil microbes decreased after the establishment of C. microphylla on moving sand dune, whereas the functional diversity of soil microbes increased with increasing age of C. microphylla plantation.

Key words: sand-fixing plant community, soil microbe, functional diversity, Biolog, Caragana microphylla, Horqin Sandy Land