Abstract: Based on the investigation data from a subtropical wetland having been abandoned from paddy agriculture for one year, a redundancy analysis was conducted on the relationships between vegetation community and soil factors in the wetland. It was found that soil moisture regime, available K and P, and pH were the main factors affecting the distribution of plant species. The common plant species could be classified into three groups, i.e., Ludwigia prostrata〖KG-*2〗-〖KG-*7〗Murdannia triquetra group (G1), Hemarthria altissima〖KG-*2〗-〖KG-*7〗Rotala rotundifolia〖KG-*2〗-〖KG-*7〗Lapsana apogonoides group (G2), and Conyza canadensis〖KG-*2〗-〖KG-*7〗Polygonum hydropiper〖KG-*2〗-〖KG-*7〗Paspalum pasaloides group (G3). G1 mainly distributed on the soils with higher available K, G2 mainly distributed in periodically flooded area, while G3 mainly distributed in drainage area and was positively correlated to soil available P and pH. Species diversity and above-ground biomass had significant positive correlations with soil pH and total K, respectively, while evenness index was significantly negatively correlated with soil available N. No significant correlations were observed among other indices.

Key words: short-acting sterilant, lethal control, seasonal breeding, mathematical model, rodent pests.