Zusammenhänge zwischen Aggregatumsatz und der Verteilung von Kohlenstoff und Phosphor im Aggregat

Bodenstrukturbildung und Aggregatumsatz beeinflussen die Verfügbarkeit von Phos-phor, einem der wenig mobilen Nährelementen im Boden. Weithin wird angenommen, dass es enge Zusammenhänge zwischen bodenökologischen Eigenschaften, wie beispielsweise der Humusform und den Aggregateigenschaften von Waldböden gibt. Arbeiten, die Aggregateigenschaften, sowie -umsatz und P-Verfügbarkeit verbinden, fehlen jedoch bisher. Wir können zeigen, dass Bodenaggregate für die Verfügbarkeit von Nährstoffen von Bedeutung sind. Im Aggregat eingeschlossene partiku-läre organische Substanz gewinnt an Wichtigkeit je schlechter der Standort versorgt ist. Dichtefraktionen unterliegen einer jahreszeitlichen Dynamik

Der König als Krieger. Zum Verhältnis von Königtum und Krieg im Mittelalter. Beiträge der Tagung des Zentrums für Mittelalterstudien der Otto-Friedrich-Universität Bamberg (13. – 15. März 2013)

Der König als Krieger – Zum Verhältnis von Königtum und Krieg im Mittelalter Kriegshandlungen waren in der mittelalterlichen Gesellschaft allgegenwärtig und oftmals eng mit dem Königtum verknüpft. Nahezu alle Könige des Mittelalters haben während ihrer Regierungszeit militärische Aktionen durchgeführt. Dabei agierten sie als Kriegsherren, militärische Anführer und immer wieder auch als aktive Kämpfer. Diese Rollen werden in den Quellen oft genug betont, etwa durch den gängigen Topos einer mitreißenden Rede unmittelbar vor der Schlacht. Gleichzeitig waren sich die Zeitgenossen jedoch der Bedeutung der persönlichen Unversehrtheit des Monarchen vollauf bewusst, womit ein Spannungsmoment zwischen der Herrschertugend der Tapferkeit (fortitudo) und der Raison des Königsamtes gegeben war. Der Sammelband analysiert anhand von verschiedenen historischen Beispielen, welche Bedeutung die Kriegsteilnahme für das mittelalterliche Herrschaftsverständnis hatte, wann, wie und in welchem Kontext die Rolle des Königs als Feldherr oder Kämpfer besonders hervorgehoben, wann sie unterdrückt oder kritisiert wurde

Global data on earthworm abundance, biomass, diversity and corresponding environmental properties

Publisher Copyright: © 2021, The Author(s).Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.Peer reviewe

Global data on earthworm abundance, biomass, diversity and corresponding environmental properties

Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change

The fate of calcium in temperate forest soils: a Ca K-edge XANES study

Calcium (Ca) plays a crucial role for plant nutrition, soil aggregation, and soil organic matter (SOM) stabilization. Turnover and ecological functions of Ca in soils depend on soil Ca speciation. For the first time, we used synchrotron-based X-ray absorption near-edge structure (XANES) spectroscopy at the Ca K-edge (4038 eV) to investigate Ca speciation in soils. We present Ca K-edge XANES spectra of standard compounds with relevance in soils (e.g. calcite, dolomite, hydroxyapatite, anorthite, clay mineral-adsorbed Ca; Ca oxalate, formate, acetate, citrate, pectate, phytate). Calcium XANES spectra with good signal-to-noise ratios were acquired in fluorescence mode for Ca concentrations between 1 and 10 mg g−1. Most standard spectra differed markedly among each other, allowing the identification of different Ca species in soils and other environmental samples as well as Ca speciation by linear combination fitting. Calcium XANES spectra obtained for samples from different horizons of twelve temperate forest soils revealed a change from dominating lithogenic Ca to clay mineral-bound and/or organically bound Ca with advancing pedogenesis. O layer Ca was almost exclusively organically bound. With increasing SOM decomposition, shares of oxalate-bound Ca decreased. Oxalate-bound Ca was absent in calcareous, but not in silicate subsoil horizons, which can be explained by microbial decomposition in the former vs. stabilization by association to pedogenic minerals in the latter soils. Synchrotron-based Ca XANES spectroscopy is a promising novel tool to investigate the fate of Ca during pedogenesis and—when performed with high spatial resolution (µ-XANES), to study aggregation and SOM stabilization mechanisms produced by Ca.BLE WaldklimafondsProjekt DEA