Soil microbial functional diversity of Eucalyptus plantation in Hainan Island

As one of the most important components in soil ecosystem，soil microbes have irreplaceable effects on nutrient and energy cycling. In the research，the changes of functional diversity of soil microbial community were analyzed by using the method of Biolog-ECO microplate culture in different soil depths of 4-year Eucalyptus plantation in western Hainan Island. The results showed that the average well color development（ AWCD） increased with incubation time，and there were significant differences among different soil layers，varying from 0.85，0.97 and 1.00（cultured for 300 hours） for 0-10 cm，10-20 cm and 20-30 cm soil layer. The microbial communities in different soil layers had similar carbon sources utilization mode； it found that amine was the highest availability of carbon sources，followed by Phenolic acids，amino acids，polymer，and carbohydrates，and carboxylic acids had the lowest utilization rate. However，the carbon utilization efficiency increased with the soil depth，the values of Shannon-Wiener index（ H），Simpson index（ D） and McIntosh index（ U） all increased with layer increasing； it