TY - GEN A1 - Wanner, Manfred A1 - Elmer, Michael A1 - Sommer, Michael A1 - Funk, Roger A1 - Puppe, Daniel T1 - Testate amoebae colonizing a newly exposed land surface are of airborne origin T2 - Ecological Indicators N2 - We hypothesized that at the very beginning of terrestrial ecosystem development, airborne testate amoebae play a pivotal role in facilitating organismic colonization and related soil processes. We, therefore, analyzed size and quantity of airborne testate amoebae and immigration and colonization success of airborne testate amoebae on a new land surface (experimental site “Chicken Creek”, artificial post-mining water catchment). Within an altogether 91-day exposure of 70 adhesive traps, 12 species of testate amoebae were identified to be of airborne origin. Phryganella acropodia (51% of all individuals found, diameter about 35–45 μm) and Centropyxis sphagnicola (23% of all individuals found, longest axis about 55–68 μm), occurred most frequently in the adhesive traps. We extrapolated an aerial amoeba deposition of 61 individuals d−1 m−2 (living and dead individuals combined). Although it would be necessary to have a longer sequence (some additional years), our analysis of the “target substrate” of aerial immigration (catchment site) may point to a shift from a stochastic (variable) beginning of community assembly to a more deterministic (stable) course. This shift was assigned to an age of seven years of initial soil development. Although experienced specialists are necessary to conduct these time-consuming studies, the presented data suggest that terrestrial amoebae are suitable indicators for initial ecosystem development and utilization. Y1 - 2015 U6 - https://doi.org/10.1016/j.ecolind.2014.07.037 SN - 1470-160x VL - 48 SP - 55 EP - 62 ER - TY - CHAP A1 - Sommer, Lars A1 - Flassig, Peter Michael A1 - Dutta, Amit Kumar A1 - Bestle, Dieter T1 - Krümmungs-Nebenbedingungen in der aerodynamischen Mehrkriterien-Optimierung von Verdichterschaufelprofilen T2 - Deutscher Luft- und Raumfahrtkongress 2008, Darmstadt, 23. bis 25. September 2008, Bd. 2 Y1 - 2008 N1 - 2008-081195 SP - 1011 EP - 1022 PB - Dt. Ges. für Luft- und Raumfahrt CY - Bonn ER - TY - GEN A1 - Sommer, Michael A1 - Höhn, Axel A1 - Breuer, Jörn A1 - Zagorski, Zbigniew A1 - Busse, J. A1 - Barkusky, Dietmar A1 - Meier, K. A1 - Puppe, Daniel A1 - Wanner, Manfred A1 - Kaczorek, Danuta T1 - Si cycling in a forest biogeosystem – the importance of transient state biogenic Si pools T2 - Biogeosciences Y1 - 2013 SN - 1726-4189 VL - 10 IS - 7 SP - 4991 EP - 5007 ER - TY - GEN A1 - Ehrmann, Otto A1 - Puppe, Daniel A1 - Wanner, Manfred A1 - Kaczorek, Danuta A1 - Sommer, Michael T1 - Testate amoebae in 31 mature forest ecosystems - densities and micro-distribution in soils T2 - European Journal of Protistology Y1 - 2012 SN - 1618-0429 N1 - Diese Publikation entstand in Zusammenarbeit mit dem ZALF e.V. und dem Büro für Bodenmikromorphologie und Bodenbiologie Creglingen (Erstautor) VL - 48 IS - 3 SP - 161 EP - 168 ER - TY - GEN A1 - Puppe, Daniel A1 - Kaczorek, Danuta A1 - Wanner, Manfred A1 - Sommer, Michael T1 - Dynamics and drivers of the protozoic Si pool along a 10-year chronosequence of initial ecosystem states T2 - Ecological Engineering N2 - The size and dynamics of biogenic silicon (BSi) pools influence silicon (Si) fluxes from terrestrial to aquatic ecosystems. The research focus up to now was on the role of plants in Si cycling. In recent studies on old forests annual biosilicification rates of idiosomic testate amoebae (i.e. TA producing self-secreted silica shells) were shown to be of the order of Si uptake by trees. However, no comparable data exist for initial ecosystems. We analyzed the protozoic BSi pool (idiosomic TA), corresponding annual biosilicification rates and readily available and amorphous Si fractions along a 10-year chronosequence in a post-mining landscape in Brandenburg, Germany. Idiosomic Si pools ranged from 3 to 680 g Si ha−1 and were about 3–4 times higher at vegetated compared to uncovered spots. They increased significantly with age and were related to temporal development of soil chemical properties. The calculation of annual biosilicification resulted in maxima between 2 and 16 kg Si ha−1 with rates always higher at vegetated spots. Our results showed that the BSi pool of idiosomic TA is built up rapidly during the initial phases of ecosystem development and is strongly linked to plant growth. Furthermore, our findings highlight the importance of TA for Si cycling in young artificial ecosystems. Y1 - 2014 U6 - https://doi.org/http://dx.doi.org/10.1016/j.ecoleng.2014.06.011 SN - 0925-8574 IS - 70 SP - 477 EP - 482 ER - TY - GEN A1 - Puppe, Daniel A1 - Ehrmann, Otto A1 - Kaczorek, Danuta A1 - Wanner, Manfred A1 - Sommer, Michael T1 - The protozoic Si pool in temperate forest ecosystems - quantification, abiotic controls and interactions with earthworms T2 - Geoderma Y1 - 2015 SN - 0016-7061 IS - 243-244 SP - 196 EP - 204 ER - TY - GEN A1 - Puppe, Daniel A1 - Höhn, Axel A1 - Kaczorek, Danuta A1 - Wanner, Manfred A1 - Sommer, Michael T1 - As time goes by—Spatiotemporal changes of biogenic Si pools in initial T2 - Applied Soil Ecology N2 - Accumulation and recycling of biogenic silicon (BSi) in terrestrial ecosystems influence fluxes of dissolved Si from the continents to the oceans, thus act as a filter in the global Si cycle. Although the biogenic control mechanism especially of phytogenic Si pools (phytoliths) has been generally recognized since decades quantitative information on other terrestrial BSi pools is surprisingly rare. For the first time terrestrial protophytic (diatom frustules), protozoic (testate amoeba shells) and zoogenic (sponge spicules) Si pools were quantified in soils of initial ecosystem states. We analyzed spatiotemporal changes of these Si pools in differently aged soils of the artificial catchment ‘Chicken Creek’ in NE Germany. Within a relatively short time span (<10 years) of ecosystem development protophytic, protozoic and zoogenic Si pool sizes increased markedly, whereat protozoic Si pools were the smallest ones with a maximum of 6.2 mg m−2. Zoogenic Si pool size (max. 22.6 mg m−2) is comparable to the one of protophytic Si pools (max. 30.5 mg m−2) although only few sponge spicules (n = 10) and spicule fragments (n = 2) were found. Differences in quantities, dynamics and resistibility against dissolution of various BSi pools indicate their possibility to influence biogeochemical Si cycling relatively rapid (protophytic and protozoic Si pools) or slow (zoogenic Si pool). Spatiotemporal changes of protophytic and protozoic Si pools within the first decade of ecosystem development seem to be mainly controlled by (biotic) small-scale environmental conditions (e.g., vegetation, food sources). Y1 - 2016 U6 - https://doi.org/10.1016/j.apsoil.2016.01.020 SN - 0929-1393 VL - 105 SP - 9 EP - 16 ER - TY - GEN A1 - Wanner, Manfred A1 - Seidl-Lampaa, Barbara A1 - Höhn, Axel A1 - Puppe, Daniel A1 - Meisterfeld, Ralf A1 - Sommer, Michael T1 - Culture growth of testate amoebae under different silicon concentrations T2 - European Journal of Protistology Y1 - 2016 SN - 1618-0429 SN - 0932-4739 VL - 56 SP - 171 EP - 179 ER - TY - GEN A1 - Puppe, Daniel A1 - Höhn, Axel A1 - Kaczorek, Danuta A1 - Wanner, Manfred A1 - Wehrhan, Marc A1 - Sommer, Michael T1 - How big is the influence of biogenic silicon pools on short-term changes in water-soluble silicon in soils? Implications from a study of a 10-year-old soil–plant system T2 - Biogeosciences Y1 - 2017 SN - 1726-4189 SN - 1726-4170 VL - 14 IS - 22 SP - 5239 EP - 5252 ER - TY - GEN A1 - Heinrich, Ingo A1 - Balanzategui, Daniel A1 - Bens, Oliver A1 - Blasch, Gerald A1 - Blume, Theresa A1 - Böttcher, Falk A1 - Borg, Erik A1 - Brademann, Brian A1 - Brauer, Achim A1 - Conrad, Christopher A1 - Dietze, Elisabeth A1 - Dräger, Nadine A1 - Fiener, Peter A1 - Gerke, Horst H. A1 - Güntner, Andreas A1 - Heine, Iris A1 - Helle, Gerhard A1 - Herbrich, Marcus A1 - Harfenmeister, Katharina A1 - Heußner, Karl-Uwe A1 - Hohmann, Christian A1 - Itzerott, Sibylle A1 - Jurasinski, Gerald A1 - Kaiser, Knut A1 - Kappler, Christoph A1 - Koebsch, Franziska A1 - Liebner, Susanne A1 - Lischeid, Gunnar A1 - Merz, Bruno A1 - Missling, Klaus Dieter A1 - Morgner, Markus A1 - Pinkerneil, Sylvia A1 - Plessen, Birgit A1 - Raab, Thomas A1 - Ruhtz, Thomas A1 - Sachs, Torsten A1 - Sommer, Michael A1 - Spengler, Daniel A1 - Stender, Vivien A1 - Stüve, Peter A1 - Wilken, Florian T1 - Interdisciplinary Geo-ecological Research across Time Scales in the Northeast German Lowland Observatory (TERENO-NE) T2 - Vadose Zone Journal Y1 - 2018 U6 - https://doi.org/10.2136/vzj2018.06.0116 SN - 1539-1663 VL - 17 IS - 1 SP - 1 EP - 25 ER - TY - GEN A1 - Puppe, Daniel A1 - Wanner, Manfred A1 - Sommer, Michael T1 - Data on euglyphid testate amoeba densities, corresponding protozoic silicon pools, and selected soil parameters of initial and forested biogeosystems T2 - Data in Brief Y1 - 2018 SN - 2352-3409 VL - 21 SP - 1697 EP - 1703 ER - TY - RPRT A1 - Keuler, Klaus A1 - Block, Alexander A1 - Ahrens, Wilfried A1 - Jacob, Daniela A1 - Rechid, Diana A1 - Kotova, Lola A1 - Kotlarski, Sven A1 - Heimann, Dietrich A1 - Zemsch, Maria A1 - Knoche, Richard A1 - Dittmann, Ernst A1 - Walter, Andreas A1 - Berger, Franz A1 - Sommer, Michael T1 - Quantifizierung von Ungenauigkeiten regionaler Klima- und Klimaänderungssimulationen (QUIRCS). Zusammenfassung der wesentlichen Ergebnisse eines Projektes des deutschen Klimaforschungsprogramms DEKLIM N2 - Das Projekt QUIRCS (“Quantification of Uncertainties in Regional Climate and Climate-Change Simulations“) ist eines von insgesamt37Verbundforschungsprojekten, die im Rahmen des Deutschen Klimaforschungsprogramms DEKLIM vom BMBF als Beitrag zum Teilbereich „Klima-forschung und Vorhersagbarkeit“ gefördert worden sind [DEKLIM, 2005]. Unter der Koordination des Lehrstuhls Umweltmeteorologie der Brandenburgischen Technischen Universität (BTU) Cottbus waren 6 Institutionen mit insgesamt 13 Mitarbeitern über 4 Jahre an der Durchführung des Projektes beteiligt. Der vorliegende Bericht gibt einen Überblick über die verschiedenen Aufgabenstellungen und fasst die wesentlichen Ergebnisse des Projektes zusammen. Y1 - 2006 UR - https://www-docs.b-tu.de/fg-meteorologie/public/publikationen/quircs_abschlussbericht.pdf ER - TY - RPRT A1 - Keuler, Klaus A1 - Block, Alexander A1 - Ahrens, Wilfried A1 - Jacob, Daniela A1 - Rechid, Diana A1 - Kotova, Lola A1 - Kotlarski, Sven A1 - Heimann, Dietrich A1 - Zemsch, Maria A1 - Knoche, Richard A1 - Dittmann, Ernst A1 - Walter, Andreas A1 - Berger, Franz A1 - Sommer, Michael T1 - QUIRCS: Quantification of uncertainties in regional climate and climate change simulations. German Climate Research Programme (2001-2006), Final Symposium 2005 N2 - The comparison of multi model runs of the reference period 1979-1993 with different observational data sets for several climate parameters enables the quantification of the model uncertainties in representing present-day climate conditions for Central Europe. The quantification is based on a number of objective distance measures which detect differences in the spatial and temporal structures of the data sets being compared. Additional climate change simulations of two 30-year periods (control and scenario simulation) are performed for the SRES B2 global change scenario. They indicate a severe warming for Germany with values of up to 4 K in summer which is much higher than the quantified uncertainty range of the regional models for this climate parameter. For precipitation in Germany, a weak reduction during the summer months is overcompensated by an increase in winter and fall. However, the simulated changes are smaller than the quantified uncertainty range for the regional models so that in particular a significant reduction of the annual precipitation in Germany cannot be stated on basis of the current simulations for the B2 scenario. Aim of the research in the context of DEKLIM A reliable assessment of possible future climate developments requires an improved understanding of climate and its variability as well as a detailed knowledge of the uncertainties of climate simulations which provide the requested information about the potential degree of future changes. The project QUIRCS focuses on the climate patterns of Central Europe and investigates the quality of currently used regional climate models and regionalization techniques by a model inter-comparison, a substantial model evaluation, additional sensitivity studies and an extensive analysis of climate data. The major scientific aims are • to quantify the uncertainties of regional climate simulations and of observed climate data, • to provide a regional climate change scenario for Europe with a particular focus on Germany, • to assess the reliability of the produced climate change signals with respect to the Collapse. KW - regional climate simulation KW - model evaluation KW - uncertainty KW - climate change KW - climate data Y1 - 2005 UR - http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.596.557&rep=rep1&type=pdf PB - DLR CY - Bonn ER - TY - RPRT A1 - Thonicke, Kirsten A1 - Rahner, Eva A1 - Arneth, Almut A1 - Bartkowski, Bartosz A1 - Bonn, Aletta A1 - Döhler, Christian A1 - Finger, Robert A1 - Freitag, Jens A1 - Grosch, Rita A1 - Grossart, Hans-Peter A1 - Grützmacher, Kim A1 - Hartman Scholz, Amber A1 - Häuser, Christoph A1 - Hickler, Thomas A1 - Hölker, Franz A1 - Jähnig, Sonja C. A1 - Jeschke, Jonathan A1 - Kassen, Rees A1 - Kastner, Thomas A1 - Kramer-Schadt, Stephanie A1 - Krug, Cornelia A1 - Lakner, Sebastian A1 - Loft, Lasse A1 - Matzdorf, Bettina A1 - Meakins, Felicity A1 - De Meester, Luc A1 - Monaghan, Michael T. A1 - Müller, Daniel A1 - Overmann, Jörg A1 - Quaas, Martin A1 - Radchuk, Viktoriia A1 - Reyer, Christopher A1 - Roos, Christian A1 - Scholz, Imme A1 - Schroer, Sibylle A1 - Sioen, Giles Bruno A1 - Sommer, Simone A1 - Sommerwerk, Nike A1 - Tockner, Klement A1 - Turk, Zachary A1 - Warner, Barbara A1 - Wätzold, Frank A1 - Wende, Wolfgang A1 - Veenstra, Tonjes A1 - Voort, Hein van de T1 - 10 Must-Knows aus der Biodiversitätsforschung Y1 - 2022 U6 - https://doi.org/10.5281/zenodo.6257476 PB - Potsdam-Institut für Klimafolgenforschung e.V. (PIK) CY - Potsdam ER - TY - GEN A1 - Ahrends, Hella Ellen A1 - Piepho, Hans-Peter A1 - Sommer, Michael A1 - Ewert, Frank A1 - Webber, Heidi T1 - Is the volatility of yields for major crops grown in Germany related to spatial diversification at county level? T2 - Environmental Research Letters N2 - Recent evidence suggests a stabilizing effect of crop diversity on agricultural production. However, different methods are used for assessing these effects and there is little systematic quantitative evidence on diversification benefits. The aim of this study was to assess the relationship between volatility of combined crop yields (denoted as standard deviation) and diversity (denoted as Shannon’s Evenness Index SEI) for standardized yield data of major crop species grown in Germany between 1977 and 2018 (winter wheat, winter barley, silage maize and winter rapeseed) at the county level. Portfolio theory was used to estimate the optimal crop area share for minimizing yield volatility. On average, results indicated a weak negative relationship between volatility and the SEI during the past decades for the case of Germany. Optimizing crop area shares for minimizing volatility reduced yield variance on average by 24% but was associated with a decrease in SEI for most counties. This was related to the finding that the stability of individual species, i.e., barley and wheat, was more effective in reducing the volatility of combined yields than the asynchronous variation in annual yields among crops. Future studies might include an increased number of crop species and consider temporal diversification effects for a more realistic assessment of the relation between yield volatility and crop diversity and test the relationship in other regions and production conditions. KW - portfolio theory KW - optimization KW - crop yield KW - NUTS 3 Y1 - 2024 U6 - https://doi.org/10.1088/1748-9326/ad7613 SN - 1748-9326 VL - 19 IS - 10 PB - IOP Publishing ER -