Correlating phosphorus extracted by simple soil extraction methods with foliar phosphorus concentrations of Picea abies (L.) H. Karst. and Fagus sylvatica (L.)

摘要

Phosphorus (P) concentrations in needles and leaves of forest trees are declining in the last years in Europe. For a sustainable forest management the knowledge of site specific P nutrition/availability in forest soils is vital, but we are lacking verified simple methods for the estimation of plant available P. Within this study, four soil P extraction methods [water (P-H2O), double-lactate (P lac), citric acid (P-cit), and sodium bicarbonate (P-HCO3)], as well as total P content of the soil (P tot) were tested to investigate which method is best correlated with foliar P concentrations of spruce [Picea abies (L.) H. Karst.] and beech [Fagus sylvatica (L.)]. Mineral soil samples from 5 depth levels of 48 forest sites of the Bavarian sample set of the second National Forest Soil Inventory (BZE II) were stratified according to tree species (spruce and beech) and soil pH (pH 6.2 and 6.2), covering the whole range of P nutrition.