Evaluation of soil nitrogen mineralization in two spring barley fields

automne autumn azote catch cropping cerdo cultivo intermedio cultivos de primavera culture de printemps danemark denmark dinamarca disponibilidad de nutrientes farmyard manure fertilisation fertilizer application fumier hiver hordeum vulgare invierno lisier loam soils lolium perenne mineralisation mineralization nitrogen nutrient availability porcin primavera printemps sandy soils seasonal variation slurry sol sableux sol sablolimoneux spring spring crops suelo arenoso suelo franco summer swine verano winter