Characteristics of nitrate and other nutrients of the subsoil under field greenhouse cultivation in Hokkaido [Japan]

abonos nitrogenados analyse de sol cultivos de invernadero fertilidad del suelo gestion du sol greenhouse crops greenhouse soils manejo del suelo nitrate nitrates nitratos nitrogen fertilizers plante de serre soil analysis soil fertility soil management sol de serre sous-sol subsoil subsuelo suelo de invernaderos