Sanjiang Plain Marsh Ecological Experimental Station (SJM) is located in one of the largest marshes distribution areas, Sanjiang Plain, which is a low plain formed by the Heilongjiang River, Songhua River, Wusuli River. The station (133°31′E，47°35′N) has an altitude of ~56 m.a.s.l, belongs to the temperate continental monsoon climate zone, with the mean annual temperature of 1.9℃, and annual rainfall of ~600 mm. The area has an annual frost-free period of 125 d and is a typical seasonal frozen area with the freezing and thawing period from early November until the middle of June in the next year. The dominated vegetation composition are Carex lasiocapa, Carex pseudocuraica, Carex meyeriana, Glyceria spiculosa, Deyeuxia angustifolia, and the soil types are mainly meadow bog soil, humus bog soil and gley white paper clay, white pulp meadow soil, etc.The main crops are soybeans and rice in this area.