Effect of water:soil ratio on phosphate release: P, aluminium and fulvic acid associations in water extracts from Andisols and Andic soils

acide fulvique aluminio aluminium andic soils andisols andosol andosoles andosols anion aniones anions canarias canary islands carbon carbone carbono complejos organominerales contenido de agua en el suelo espagne extractos extracts extrait fertilidad del suelo fosfatos fosforo fulvic acids organomineral complexes ph phosphate phosphates phosphore phosphorus soil soil fertility soil water content sol sol volcanique solubilidad solubility spain suelo teneur en eau du sol volcanic soils