Das Projekt "A novel tool to trace fire-derived organic matter deposition in a high-resolution sedimentary record of the past 250 years" wird vom Umweltbundesamt gefördert und von Universität Zürich, Geographisches Institut durchgeführt. Black carbon (BC) residues from the incomplete combustion of vegetation and fossil fuels are ubiquitous in soil, sediment and water. Due to its stability, BC is an important component of the slow cycling global carbon pool. Analysis of BC in environmental matrices such as soils and sediments is complicated by its diverse nature. Sediments are the quantitatively most important sink in the global black carbon cycle and represent archives of BC deposition on local and regional scales, but the identification and apportionment of the BC sources (fossil fuel combustion versus vegetation fires) remain unclear to date. Benzene polycarboxylic acids (BPCA) are molecular markers specific for BC and are used to measure quantity and quality of BC. The method provides information about the degree of condensation and allows characterization of different forms of BC (e.g. charcoal, soot). Recent advances in BPCA analysis improved the method in terms of sample preparation and made analyses faster and more accurate. Compound specific radiocarbon (14C) dating is a powerful tool in geochemistry and archaeological sciences to trace the fate of specific molecules in soils and sediments. Up to now, 14C measurements are inaccurate for BC, as established methods measure 14C contents of oxidation resistant bulk carbon. In the proposed research project, I will follow a novel approach for BPCA separation with subsequent determination of its 14C contents. This technique will allow to precisely estimate the apportionment of sources of BC found in sediments and the age of black carbon in soils. In this project I will take advantage of an existing set of well-dated lake sediment samples. These sediment cores feature undisturbed lamination, thus providing a high-resolution record of BC depositions over more than two centuries. Analyzing this unique sample set, the qualitative and quantitative information yielded by the BPCA method and the novel approach for radiocarbon dating of BC molecular markers will be used to construct a historical record of black carbon emissions. The data will be used to apportion the measured BC concentrations to either fossil fuel or biomass burning since pre-industrial times and to identify the type of BC being preferentially preserved in aquatic sediments. The outcome of the project will help to elucidate the environmental fate of BC and will be an important contribution to the accurate calculation of a global BC budget.
Das Projekt "Genetische Verbesserung der Holzqualitaet (FAIR FP4)" wird vom Umweltbundesamt gefördert und von Universität für Bodenkultur Wien, Institut für Botanik durchgeführt. The aim of this project is to increase the efficiency with which tree breeders select genotypes of economic value to foresters and wood users. Objectives are the estimation of genetic parameters for wood properties known to influence the yield and value of end products. Further, we identify molecular markers for a subset of these wood properties, for use in marker assisted selection and finally to determine the economic weights of these wood properties, for use in selection indices.