| Summary: | Revegetation by planting shrubs on moving sand dunes is widely used to control desertification in arid/semi-arid areas. The soil including microbial community can gradually be improved along with plantation development. The purposes of this study were (1) to investigate the responses of microbial communities involved in the mineralization of soil organic phosphorus (OP) and dissolution of inorganic P (IOP) in the development of sand-fixating plantation and (2) to discuss the interactions between P turnover microbial communities and soil properties. We assessed the compositions of soil <i>phoD</i> gene (one of the Pho regulons encoding alkaline phosphomonoesterases) and <i>gcd</i> gene (encoding glucose dehydrogenase) in microbial community by using high-throughput Illumina MiSeq sequencing in a chronosequence of <i>Caragana microphylla</i> plantations (0-, 10-, 20-, and 37-year plantations and a native <i>C. microphylla</i> shrub forest) in Horqin Sandy Land, Northeast China. Soil properties including soil nutrients, enzymatic activity, and P fractions were also determined. The abundance of <i>phoD</i> and <i>gcd</i> genes linearly increased with the plantation age. However, the diversity of soil <i>phoD</i> microbes was more abundant than that of <i>gcd</i>. The <i>phoD</i> gene abundance and the fractions of total OP and IOP were positively correlated with the activity of phosphomonoesterase. Actinobacteria and Streptomycetaceae were the dominant <i>phoD</i> taxa, while Proteobacteria and Rhizobiaceae were the dominant <i>gcd</i> taxa. Plantation development facilitated the progressive successions of soil phoD and gcd communities resulting from the increase in the abundance of dominant taxa. Total soil N, NH<sub>4</sub>-N, and available K were the main factors affecting the structures of <i>phoD</i> and <i>gcd</i> communities, while pH was not significantly influencing factor in such arid and nutrient-poor sandy soil. Many <i>phoD</i> or <i>gcd</i> OTUs were classified into <i>Rhizobium</i> and <i>Bradyrhizobium</i>, suggesting the coupling relationship between soil P turnover and N fixation.
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