About HARAGUCHI NOBURO
About 農研機構 農村工研
About WAKASUGI KOSUKE
About 農研機構 農村工研
About 日本土壌肥料学雑誌
About rotation from paddy to other crop
About paddy field
About impounding
About drainage (water)
About preparation (servicing)
About irrigation canal
About drainage canal
About groove
About ridging (soil preparation)
About underdrain
About ground water level
About open channel
About infrastructure improvement
About infrastructure improvement
About Agricultural engineering
About 水田輪作
About フレームワーク
About 土壌学
About 植物栄養学
About 展開
About 田畑輪換
About 水田
About 基盤
About 排水管理