NIR-Methoden zum P-Monitoring in Waldböden

Previous nation-wide forest soil inventories have indicated that a significant proportion of forest stands may be P limited. However, this assessment is based almost solely on leave and needle tissue concentrations. So far, only total soil P has been determined in these large scale inventories. Determinations of P fractions of different availability for plant uptake are commonly very onerous and expensive and have therefore not been included in a standard analytical protocol. This limits the interpretation of trends in P availability in forests and the analysis of possible causes for changes. Therefore, this project aims to develop alternative methods to quantify soil P fractions based on their spectral properties. Specifically, this project will assess the Hedley fractionation method to quantify soil P pools of different availability in German forest soils. It will further attempt to predict these P fractions on the basis of their spectral propertiess.