About NAKAGAWA MASAHIKO
About 北海道総合研究機構 林試 道東支場
About 北海道林業試験場研究報告
About forest
About forest soil
About chemical property of soil
About biota
About vegetation
About Larix kaempferi
About Abies sachalinensis
About Betulaceae
About secondary forest
About artificial forest
About Picea jezoensis var.hondoensis
About forest stand
About surface soil
About acidity(degree)
About Picea abies
About forest physiognomy
About Betula maximowicziana
About Picea glehnii
About Forest biology in general
About Soil chemistry
About 森林
About 土壌
About 林相
About 表層土壌
About 酸性度