[Ecological distribution of soil microorganism in artificial greenbelt in hinterland of Takilimakan Desert and their relations with soil factors].

Studies on the distribution of soil microorganisms in the artificial greenbelt in hinterland of Takilimakan Desert and the effects of soil features on the distribution showed that under saline water irrigation, the activities of soil microorganisms increased sharply, and the soil structure and nutrient status were improved. Among soil microorganisms, bacteria were predominant, actinomyces were the next, and fungi were the least. There were more microorganisms in upper than in deeper soil layers. Soil microorganisms near shelter-forest had a higher activity, and their quantities over 3 m from shelter-forest were almost equal to those in shifting sand. The quantities of soil microorganisms varied with seasons, and there were distinct differences among different sites of forests. Among the measured 11 soil factors, the interactions between pairs of soil available phosphorus-available potassium, organic matter-available potassium, available nitrogen-available potassium, available nitrogen-available phosphorus, organic matter-available phosphorus, available phosphorus-available nitrogen, total nitrogen-available potassium, available potassium-available phosphorus, total nitrogen-available phosphorus, and water contents-available nitrogen were significant, with the correlation coefficients of 1.37-2.58. The direct effects of available phosphorus, available nitrogen, and total nitrogen on the microbial quantity were significant, with the coefficient of 1.01-2.58.