Relationship between the gravel content in the soil and physico-chemical properties and crop growth. (1) Survey on the distribution of gravel content in Korean soil

capa arable del suelo couche arable crecimiento croissance crops cultivos grava gravel gravier growth korea republic land use paddy soils plante de culture soil soil chemicophysical properties sol sol de moyenne altitude subsoil subsuelo suelo suelo de altura top soil upland soils utilisation des terres