Nutrient concentrations in Pinus radiata D Don needles in the Basque Country (Spain): a preliminary classification of parameters and sites

aptitude des terres azote calcio calcium cation cationes cations chemical composition composition chimique espagne feuille fosforo hojas land suitability leaves magnesio magnesium manganese manganeso nitrogen nutrition des plantes phosphore phosphorus pinus radiata plant nutrition potasio potassium site factors spain