2013 Fiscal Year Final Research Report

Estimation of degree of volcanic ash additions for decision to distribution high functional soils in forest lands of Japan

Research Project

Project/Area Number	23780177
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Forest science
Research Institution	Forestry and Forest Products Research Institute
Principal Investigator	IMAYA Akihiro 独立行政法人森林総合研究所, 立地環境研究領域, 主任研究員 (60353596)
Project Period (FY)	2011 – 2013
Keywords	火山灰土壌 / 全国評価 / 酸性シュウ酸塩可溶アルミニウム / アンドソル
Research Abstract	The addition of volcanic ash to forest soil was evaluated by the concentration of Al extracted by acid oxalate and the gravel content in soil samples collected in ca.800 plots all over Japan. Twenty percent of forest soils were estimated to be volcanic ash soil and 60% of those were considered to be somewhat contained volcanic ash. The volcanic ash addition rate was high in the soils which were distributed in the area near volcanoes, while the soils having highly volcanic ash were only distributed on the flat or moderate slope in remote area from volcanoes. It was observed that the forest soils, having higher volcanic ash, showed higher carbon stock. We concluded that the addition of volcanic ash enhanced the carbon content in Japanese forest soils.