Abstract: By using RS and GIS techniques and the data of land cover and soil rel ative humidity in 2005, the regions to be preserved and those suitable for wetla nd restoration in Sanjiang Plain were ascertained, and the site selection model for the wetland restoration was established via the introduction of proximity cr iterion and patch size criterion. In the meantime, the potential grades of the r estoration were analyzed, and the sites’ spatial position and priorities for th e restoration were determined. The results showed that in the present wetland re storation regions, farmlands, especially those with high soil relative humidity, were the main sources for wetland restoration. The area of first-grade restoration region was 529261 hm2, accounting for 486% of the total area of Sanjiang Plain. Because of its low terrain and plentiful water, this region had great potential of restoring to wetland, and was the region of implementing wet land restoration in recent years. The area of second-grade restoration region was 73724 hm2, accounting for 068% of the total. This region had larg er patch area, and was not far from the extant wetland and water body. If it cou ld be restored to wetland, this region would contribute more to the further incr ease of the connectivity among wetland patches and the decrease of habitat fragm entation, being able to be used for wetland restoration in mid- and long terms. Third-grade restoration region was widely distributed in the Plain, ac counting for 2111% of the total. Considering of the importance of Sanjiang Pla in as the commodity grain and bean base in China and the present economic develo pment level, this region didn’t need to implement wetland restoration at presen t.

Key words: Alcohol extract from Mikania micrantha, Panonychus citri, Control effect