Steady state of the soil organic matter in the long-term field experiments

altitud altitude capa arable del suelo carbon carbone carbono chimie du sol classification des sols couche arable engrais organique environmental temperature farmyard manure fertilidad del suelo fertilisation fertilizer application field experimentation fumier inorganic fertilizers organic fertilizers ph del suelo ph du sol precipitation site factors soil chemistry soil classification soil fertility soil organic matter soil ph soil texture temperatura ambiental textura del suelo texture du sol top soil