Incorporation of straw in continuous growing of spring barley, 2: Influence of straw and stubble tillage upon the soil content [of carbon, nitrogen, potassium and phosphorus]

azote barley barley straw carbon carbone carbono cebada chimie du sol enfouissement enterrado fosforo incorporation labranza nitrogen orge paille d'orge paja de cebada phosphore phosphorus potasio potassium soil chemistry tillage travail du sol