Abstract: An investigation was conducted on the surface (0-10 cm) soil nutrient contents and enzyme activities in the wetlands with typical hygrophilous vegetation communities in Poyang Lake. There existed distinct differences in the soil nutrient contents and enzyme activities among the wetlands. The contents of soil organic matter, total and available nitrogen, and total and available phosphorous were higher in the wetlands with Carex cinerascens community and Polygonum hydropiper community, but obviously lower in the wetland with Phragmites communis community. Also, in the wetlands with C. cinerascens community and P. hydropiper community, the activities of soil sucrase and proteinase were higher, and the soil urease and acidic phosphatase activities were the highest, which suggested that the transformation rates of soil carbon, nitrogen, and phosphorus in the two wetlands were higher than those in the others. On the contrary, the wetlands with P. communis+Miscanthus sacchariflor community and P. communis community had the lowest activities of soil sucrase, proteinase, urease, and acidic phosphatase. Comparatively, soil polyphenol oxidase activity was the highest in the wetland with P. communis community, followed by in that with C. argi community, P. hydropiper community, C. cinerascens community, and Typha angustifolia community. Correlation analysis showed that there were no significant correlations between soil polyphenol oxidase activity and soil nutrient contents, but significant positive correlations were observed between the activities of soil sucrase, urease, proteinase, and acidic phosphatase and the contents of soil organic matter, total nitrogen, and available nitrogen, suggesting that the activities of these soil enzymes could indicate the evolution dynamics of soil quality in wetland.

Key words: Fusarium 9568D, Abiotic Dracaena cochinchinensis, Blood resin