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Camellia is a kind of peculiar oil resouce with a brightly exploitative prospect in China. Deficiency of measures for many years, some ecological problems followed up in Oiltea camellia Stands, such as thickets of weeds, decline of forestland and serious occurrence of pests and disease. The microorganisms populations and enzyme activities in soil were used to be the biological indicators to reflect these problems. It was significant to study the annual change of soil microorganisms populations and enzyme activities in Oiltea Camellia Stands.We analysed the distribution of the microorganisms populations and enzyme activities under different stand age and different culture measure; meanwhile, separated and selected inorganic phosphate-solublizing Microorganisms from camellia soil.The results shows:(1) The distribution of soil microorganisms was greatly influenced by different culture measures.The relation with the quantity of total microorganisms was that:The farming land(19.64×105/g·dry soil)> mowing land(13.9×105/g·dry soil)>none-tending land(10.4×105/g·dry soil). The total and each number of three main species of microorganisms had obvious differences under different age. Along with the age growth, the total of microorganisms under different age showed up a trend---"low-high-low". The highest quantity of total of microorganisms, bacteria, fungi, actinomyces were appeared in mid-maturation forest, the minimum amount of total microorganisms, bacteria, fungi were appeared in sapling forest.The season change induced the living environment change of microorganisms, so the type and quantity of microorganisms changed accordingly. The changeful tendency of soil microorganism quantity during four months was that quantities of soil bacteria in July, October higher than in April and December, quantities of soil fungi and actinomyces in July lowest than other three month. The amount of the soil microorganisms have evident gradient. With the depth of soil increasing the microbial qunantity rapidly reduce. (2) The activity of urease, sucrase and catalase under the managements of farming and mowing were significantly or extremely significantly higher than thats under none-tending land. The soil enzyme activities also had obvious difference under different stands. At the layer of 0-20cm soil profile, the unease activity in the old-growth(32.87mg/g·24h) forest was upper which compared with others, that in sapling forest (16.58 mg/g·24h)was very lower; soil sucrase and soil catalas in the mid-maturation forest (1.46ml/g·23h,1.14 ml/g·20min)were upper which compared with others, thats in sapling forest(0.98 ml/g·23h,0.72 ml/g·20min) were very lower.The activity of soil enzyme also changed with the season. All highest activity of three main soil enzyme showed up in April, decreased in July, and increased in August. After that, in December, the activity of soil unease and soil catalas were decreased, only soil sucrase shown the sign to up. The soil urease, invertase had significantly vertical distribution characteristics in the soil profile, but thats of soil catalas did not obvious.(3) A correlation exists among soil microorganism, soil enzyme activity and soil nutrients. The bacteria had a extremely significant positive correlation with soil OM (0.9287)and Avilable P(0.9500); The funji and the actinomucete showned positive correlation with soil OM(0.7680,0.7103), Total N(0.7932,0.7563), Available nitrogen(0.7812,0.7189), and Avilable P(0.7349,07396). Soil urease had extremely significant correlation with the other four major fertility factor; The correlation among soil sucrase, catalase with the other four major fertility factor did not reach the significant level.(4) One inorganic phosphate-solublizing bacterium, named TY05, was isolated from Camellia soil sample, and it’s effective phosphorus can reached to 153.92 mg/L. The strain were identified as Pseudomonas by colony characterization, morphological characterization, physiological and biochemical reactions, and relevant literature.
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