2018 Volume 8 Pages 45-52
Recently, changes in vegetation cover, such as bare ground formation and plant species composition change presumably by disturbances of agricultural and development and deer＇s trampling, have been remarkably observed in Kushiro Marsh. Vegetation change is known to alter soil nutrient dynamics for forests, but not to wetlands, as vegetation is closely related to soil. In order to understand basic information associated with nutrient cycles of various wetland vegetation types in Kushiro Marsh, we clarified stock of minerals and nitrogen mineralization rate in different vegetation types. The results showed that NH4+ concentration in soil solution was low when compared with other wetland ecosystems. Stock of extractable ammonium-nitrogen in 0-5cm soil were highest in fen than other vegetation types. Stock of extractable ammonium-nitrogen in 0-5cm soil was larger in fen and bog. Throughout the finding, due to the geographical morphology, fen in Kushiro Marsh is expected to have large stock of extractable ammonium-nitrogen compared to neighboring sites.