The content of mineral nitrogen in the soil after growing several vegetables and fodder crops under existing conditions in Laerdal in western Norway

azote chimie du sol climatic factors crop residues crop yield facteur climatique fosforo hortalizas (plantas) nitrogen noruega norway phosphore phosphorus potasio potassium rendement des cultures rendimiento de cultivos residuos de cosechas rotation culturale rotational cropping soil chemistry vegetable crops