About AOYAMA M
About Hirosaki Univ., Hirosaki, JPN
About KUMAKURA N
About Hirosaki Univ., Hirosaki, JPN
About Soil Science and Plant Nutrition
About soil organic matter
About carbon nitrogen ratio
About Soil chemistry
About 無機肥料
About 家畜
About 厩肥
About アンド土
About 有機物
About 質的変化