TY - CHAP A1 - Fischer, Thomas A1 - Subbotina, Maria T1 - Soil texture and climatc conditions for biocrust growth limitation: a meta analysis T2 - European Geosciences Union, General Assembly 2015, Vienna, Austria, 13 April - 17 May 2015 Y1 - 2015 N1 - EGU2015-1197 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - GEN A1 - Wang, Haijing A1 - Fischer, Thomas A1 - Wieprecht, Wolfgang A1 - Möller, Detlev T1 - A predictive method for volatile organic compounds emission from soil: Evaporation and diffusion behavior investigation of a representative component of crude oil T2 - Science of the Total Environment Y1 - 2015 U6 - https://doi.org/10.1016/j.scitotenv.2015.05.063 SN - 1879-1026 VL - 530-531 SP - 38 EP - 44 ER - TY - GEN A1 - Wang, Haijing A1 - Geppert, Helmut A1 - Fischer, Thomas A1 - Wieprecht, Wolfgang A1 - Möller, Detlef T1 - Determination of Sucrose in Honey with Derivatization/Solid-Phase-Microextraction and Gas-Chromatography/Mass Spectrometry. T2 - Journal of Chromatographic Science N2 - A new method for the determination of sucrose in honey with derivatization solid-phase microextraction and gas chromatography/mass spectrometry (D-SPME–GC/MS) was developed. The method incorporates a sample derivatization with acetic anhydride using N-methylimidazole as the catalyst and the subsequent enrichment of the analyte in a Polyacrylate-SPME fiber. Results show that 100 µL N-methylimidazole and 800 µL acetic anhydride were sufficient to complete the acetylation for sucrose in 100 µL aqueous sample at room temperature. For SPME, an enrichment time of 30 min was sufficient. SPME was performed by immersing the fiber into the solution with additional vibration. Then, the analyte was desorbed for 5 min at 280°C in the GC/MS injection port with splitless mode. The present method exhibits good linearity at a concentration range of 0.3–8% of sucrose in honey with excellent regression (R = 0.9993). The method has been successfully applied to the control of sucrose adulteration in honey. Y1 - 2015 U6 - https://doi.org/10.1093/chromsci/bmv044 VL - 53 IS - 9 SP - 1427 EP - 1431 ER - TY - GEN A1 - Subbotina, Maria A1 - Fischer, Thomas A1 - Mikhailova, Lyudmila A1 - Losev, Daniil T1 - The influence of postagrogenic transformation on biological properties of soddy shallow clay loam podzolic soil in the Preduralie. T2 - Agriculture & Forestry Y1 - 2016 U6 - https://doi.org/10.17707/AgricultForest.62.1.06 SN - 1800-6492 VL - 62 IS - 1 SP - 59 EP - 63 ER - TY - CHAP A1 - Ziems, Christian A1 - Fischer, Ulrich A1 - Krautz, Hans Joachim A1 - Luschtinetz, Thomas A1 - Lehmann, Jochen T1 - Project presentation-Novel 3D porous electrode materials for more efficient alkaline water electrolysis-AEL3D T2 - Nutzung regenerativer Energiequellen und Wasserstofftechnik 2016, 23. Symposium Nutzung Regenerativer Energiequellen und Wasserstofftechnik, Stralsund, 3. - 5. November 2016 Y1 - 2016 SN - 978-3-9817740-1-6 SP - 175 EP - 181 PB - Fachhochschule CY - Stralsund ER - TY - GEN A1 - Fischer, Thomas T1 - Humic supramolecular structures have polar surfaces and unpolar cores in native soil T2 - Chemosphere N2 - It was the aim of our study to prove the hypothesis that humic substances (HS) in native soil are spatially arranged in descending order of polarity, meaning that highly polar supramolecular subunits shield less polar subunits against the free soil solution and form layers of descending polarity. To address this aim, we consecutively extracted humic substances from soil with 8 M (HS1), 4 M (HS2), 2 M (HS3), 1 M (HS4) and 0.5 M LiCl (HS5) solution in 0.2 M LiOH after Cu²⁺ adsorption in batch soil column experiments. Adsorption was performed for 1, 10 and 60 min with concentrations ranging from 9.5 to 110 mg L¹⁻Cu²⁺ in 0.02 M CaCl₂ solution. We assumed that high ionic strength facilitates extraction of most polar organic compounds, with polarity of the extracted HS decreasing with decreasing ionic strength, and that Cu extracted together with the successive HS solely formed coordination complexes, facilitating its use as a tracer for organic matter studies. We hypothesized a delayed Cu adsorption on the less polar fractions in case of spatial shielding due to interception on overlying fractions, and a concurrent Cu adsorption in case of random spatial arrangement. It was concluded that humic substances are shielded against each other in the order of descending polarity of the supramolecular subunits (free soil solution | HS1 | HS2 | HS3 | HS4 | HS5). Y1 - 2017 UR - http://www.sciencedirect.com/science/article/pii/S0045653517308317 U6 - https://doi.org/10.1016/j.chemosphere.2017.05.125 SN - 1879-1298 VL - 183 SP - 437 EP - 443 ER - TY - GEN A1 - Kuhn, Ramona A1 - Tóth, Elisabeth A1 - Geppert, Helmut A1 - Fischer, Thomas A1 - Martienssen, Marion T1 - Identification of the Complete Photodegradation Pathway of Ethylenediaminetetra(methylenephosphonic acid) in Aqueous Solution T2 - Clean - soil, air, water : a journal of sustainability and environmental safety N2 - This study aims at investigating the abiotic degradation pathway of ethylenediaminetetra(methylenephosphonic acid) (EDTMP) simulated applying UV irradiation. The degradation of EDTMP and formation of degradation products was determined using LC-MS and ³¹P-NMR. In the laboratory scale experiments, EDTMP was degraded within 30 min and the degradation products, iminodi(methylenephosphonic acid) (IDMP), ethylaminobis(methylenephosphonic acid) (EABMP), and amino- (methylenephosphonic acid) (AMPA), were simultaneously released. IDMP was the main degradation product of EDTMP. Therefore, we conclude that the initial cleavage of EDTMP is a heterolytically driven process, which starts the degradation process at the intramolecular C-N bond. In contrast, the main product of a possible homolytic C-C cleavage of methylaminobis(methylenephosphonic acid) could not be confirmed with either LC-MS or ³¹P-NMR. Additionally, there was no evidence for a primary attack on the C-P bond. All identified degradation products of EDTMP have been mineralized to carbon dioxide (CO₂). Three additional degradation products (M1, M2, and M3) have been found using the ³¹P-NMR analysis but have not yet been quantified using LC-MS. We assume that the unidentified degradation product M1 is related to m/z 312, M2 to m/z 341, and M3 to m/z 409. Thus we concluded that EDTMP undergoes photochemical conversion to IDMP, the main degradation product. EABMP and AMPA also accumulate, but in smaller amounts. All intermediates are further mineralized to CO₂. KW - EDTMP KW - LC-MS KW - 31P-NMR KW - Phosphonates KW - Photodegradation Y1 - 2017 U6 - https://doi.org/10.1002/clen.201500774 SN - 1863-0669 VL - 45 IS - 5 SP - 1 EP - 8 ER - TY - CHAP A1 - Radow, Georg A1 - Breuß, Michael A1 - Hoeltgen, Laurent A1 - Fischer, Thomas ED - Sharma, Puneet ED - Filippo, Maria Bianchi T1 - Optimised Anisotropic Poisson Denoising T2 - Image Analysis, 20th Scandinavian Conference, SCIA 2017, Tromsø, Norway, June 12–14, 2017, Proceedings, Part I Y1 - 2017 SN - 978-3-319-59126-1 SN - 978-3-319-59125-4 U6 - https://doi.org/10.1007/978-3-319-59126-1_42 SP - 502 EP - 514 PB - Springer CY - Cham ER - TY - GEN A1 - Busse, Ralph-Peter A1 - Fischer, Gert A1 - Gebauer, Gert A1 - Höfler, Frank A1 - Junker, Sabine A1 - Kramer, Thomas A1 - Opperskalski, Stephan A1 - Potthoff, Ulrich A1 - Remus, Ricardo A1 - Schlamkow, Christian A1 - Schmidt, Wolfgang A1 - Scobel, Ekkehard A1 - Stopp, Horst A1 - Strangfeld, Peter A1 - Trang, Ngyen Thi Thu A1 - Völker, Eduard A1 - Vukorep, Ilija A1 - Weidhase, Frieder A1 - Winzer, Reinhard ED - Stopp, Horst ED - Strangfeld, Peter T1 - Floating Architecture - Construction on and near water T1 - Schwimmende Architektur – Bauen am und auf dem Wasser N2 - The publishers are receiving more and more inquiries about the topic “Floating Architecture”, particularly about technical details, water chemistry, as well as ice and wave problems. Since there is a lack of technical literature on this topic, most students working on projects or theses related to this topic send their inquiries. A time of general and quick changes results in a large number of daily publications. Therefore it is difficult to understand why there is a lack of lit-erature about floating structures. One has to consider that sea levels will continue to rise and consequently a larger number of people will have to live on the surface of the sea. Obviously, some expert knowledge is required which needs a longer period of time to be gained through scientific advancements and experience. The publishers, who have been dealing with the topic of floating houses for some years, are grateful to the authors for their agreement to allow the publication of their papers on floating architecture. These papers were mainly prepared for two conferences on floating architecture held in the study centre of the IBA building, Großräschen. Therefore, the reader should know that, along with the usual papers, only a selection of self-explaining transparencies is shown in order to meet the printing requirements. The included list of both the authors and their addresses makes it easy for interested people to send any inquiries to them. A short introduction as well as an outlook at the end of each paper is meant to draw attention to current events in order to be able to promptly identify opportunities and risks connected with living on the water. KW - Floating architecture KW - Floating buildings Y1 - 2017 SN - 978-3-643-90910-7 PB - LIT-Verlag CY - Berlin ER - TY - GEN A1 - Mykhailova, Larysa A1 - Fischer, Thomas A1 - Iurchenko, Valentina T1 - Microbial activity and decomposition of soil organic matter in roadside soils contaminated with petroleum hydrocarbons T2 - CLEAN - Soil Air Water N2 - Petroleum hydrocarbons (PHs) are the most widespread organic pollutants of roadside soils, the reclamation of which is costly due to large areas affected, and natural PHs biodegradation is the only way of mitigating negative ecological consequences. This study aimed to investigate the microbial response to PHs in roadside soils and to identify soil organic matter (SOM) and PHs involved in biodegradation processes. To address this aim, soil respiration is related to light (chain‐length ≤C14) medium (C15–C27), and heavy fractions (≥C28) of total PHs, and to SOM components: carbohydrates, proteins, lignin, aliphates, carbonyl/carboxyl, and char amounts of soils sampled at distances of up to 100 m from three roads in Kharkiv, Ukraine. A close relation between soil respiration and ratio of the light fraction to the sum of medium and heavy alkane fractions indicate the preferential mineralization of more biodegradable light PHs fractions. A positive relation between soil respiration and carbohydrate C, as well as negative correlation with aliphatic C, indicate preferred degradation of carbohydrates compared to more recalcitrant aliphates. Carbohydrate content increased and aliphatic C decreased with distance from the roads, and carbohydrates decreased with PHs concentration, indicating increased degradation of carbohydrates at high PHs concentrations (positive priming). It is concluded that microorganisms generate the energy required for PHs degradation by enhanced oxidation of native SOM where carbohydrates were of paramount importance. Y1 - 2018 U6 - https://doi.org/10.1002/clen.201800132 SN - 1863-0669 ER - TY - GEN A1 - Kuhn, Ramona A1 - Jensch, Robert A1 - Bryant, Isaac Mbir A1 - Fischer, Thomas A1 - Liebsch, Stephan A1 - Martienssen, Marion T1 - The influence of selected bivalent metal ions on the photolysis of diethylenetriamine penta(methylenephosphonic acid) T2 - Chemosphere N2 - DTPMP is predominantly utilized as scale inhibitor. We investigated the reaction rates and degradation mechanism of DTPMP with and without addition of Fe²⁺, Mg²⁺ and Ca²⁺ by performing LC/MS and ³¹P-NMR analyses. DTPMP undergoes conversion with and without addition of bivalent metal ions. The initial cleavage of DTPMP is initiated at the C-N bond leading to release of IDMP as its major breakdown product. The release of smaller quantities of EABMP and AMPA confirmed the nucleophilic attack on the DTPMP amines. Oxidation of Fe²⁺ to Fe³⁺ during the initial 30 min indicated an intramolecular electron transfer changing the electron density distribution at the nitrogen centre, which increased the radical attack during UV irradiation. Independent of the fact that Fe acted as catalyst and Mg²⁺ and Ca²⁺ acted as reactants, we found no significant differences in their degradation mechanisms. However, the reaction rates were strongly affected by the addition of the bivalent metal ions as Fe²⁺ accelerated most DTPMP degradation followed by Mg²⁺ and Ca²⁺. The UV treatment without metal ion addition was four times slower compared with Fe²⁺ addition. We conclude that in environments rich in ferrous iron and/or at reduced redox potential, photolysis of DTPMP will be catalysed by iron and will lead to accumulation of IDMP, EABMP and AMPA and several other none-quantifiable breakdown products. KW - DTPMP KW - Ferrous ion KW - LC/MS KW - Phosphonates KW - Photolysis Y1 - 2018 U6 - https://doi.org/10.1016/j.chemosphere.2018.07.033 SN - 0045-6535 IS - 210 SP - 726 EP - 733 ER - TY - GEN A1 - Schmidt, Thomas A1 - Ahrens, Christian A1 - Flege, Jan Ingo A1 - Jaye, Cherno A1 - Fischer, Daniel A. A1 - Falta, Jens T1 - Growth of Epitaxial 3,4,9,10-Perylene Tetracarboxylic Dianhydride on Bi-Terminated Silicon T2 - Journal of Physical Chemistry C N2 - The epitaxial quality of thin films crucially depends on their interaction with the substrate. Up to now, Ag-terminated Si(111) has been employed as the model substrate for the growth of 3,4,9,10-perylene tetracarboxylic dianhydride (PTCDA) on semiconductors. In this study, we will show that Bi termination results in PTCDA films of superior epitaxial quality. We have studied the growth of PTCDA on bismuth-passivated Si(111) in detail by means of spot profile analysis of low-energy electron diffraction (SPA-LEED), X-ray photoemission spectroscopy (XPS), near-edge X-ray absorptionfine structure (NEXAFS), and scanning tunneling microscopy (STM). The XPS results reveal the presence of intact PTCDA molecules on the surface upon adsorption. NEXAFS data indicate the PTCDA molecules being oriented with their molecular plane parallel to the surface. STM shows a very smooth growth front of the PTCDA film, preserving the step structure of the substrate. High-resolution SPA-LEED data demonstrate the presence of a multidomain surface with a rich variety of PTCDA surface structures, which were identified to be most prominently herring-bone polytypes. However, in the monolayer range, quadratic brick-wall structures and a nearly square-like structure as well as a perylene-like structure have also been found. Despite the simultaneous presence of multiple domains, the individual domains show excellent lateral ordering, with larger domain sizes as compared to the case of Ag-terminated Si(111). KW - dianhydride KW - Bi-terminated silicon KW - spot profile analysis of low-energy electron diffraction (SPA-LEED) KW - X-ray photoemission spectroscopy (XPS) KW - near-edge X-ray absorptionfine structure (NEXAFS) KW - scanning tunneling microscopy (STM) Y1 - 2019 U6 - https://doi.org/10.1021/acs.jpcc.8b10396 SN - 1932-7447 SN - 1932-7455 VL - 123 IS - 12 SP - 7097 EP - 7109 ER - TY - GEN A1 - Fischer, Thomas T1 - PCA-based Supervised Identification of Biological Soil Crusts in Multispectral Images T2 - MethodsX N2 - It was the aim of the method development to classify types of various biological soil crusts (biocrusts) using principle component analysis (PCA) on multispectral images. To address this aim, visible (RGB) and NIR images of bare sandy soil, algal and moss biocrusts were registered, per channel reflection values were determined using a calibration color chart on a pixel basis, and a PCA was performed on the unfolded RGB-NIR reflectance hypercubes (i.e. three-dimensional hypercubes were transformed into x.y × λ 2D-matrices with λ channels serving as variables for PCA). The classification approach was based on the hypothesis that biocrust types map specifically in PCA ordination plots, meaning that distinct regions in ordination plots may be assigned specifically to individual biocrust types. Reallocation of the pixels assigned to biocrust types to their respective image coordinates would then yield biocrust classification plots. Allows manual selection of features or identification of given features in PCA ordination plots. Fully permits the selection of relevant and omission of irrelevant, as well as identification of unknown classes. It is not restricted to RGB-NIR multispectral data only, but may be applied to any type of multimodal imaging data. Y1 - 2019 U6 - https://doi.org/10.1016/j.mex.2019.03.013 SN - 2215-0161 VL - 6 SP - 764 EP - 772 ER - TY - GEN A1 - Hinz, Christoph A1 - Hafar, Brian A1 - Fischer, Thomas T1 - Heavy metal mobilisation of salt affected soils and sediments: Assessing the role of chloride complex formation. T2 - European Geosciences Union, General Assembly 2019, Vienna, Austria, 7–12 April 2019 N2 - Terrestrial and aquatic ecosystems are increasingly exposed to high level of salt (NaCl) concentrations. Impacts of increased salt concentration on mobilisation of heavy metals have been shown for road side soils receiving de-icing salt, for sediments and soils exposed to salt water intrusions, and soils and aquifers receiving runoff from salt mines. In fact, this study was motivated by the impact of salt dumps on soil and groundwater observed for potash mines in the central part of Germany. The objectives of this contribution is to asses the impact of NaCl concentration on heavy metal mobilization using speciation modelling. In particular, we focus on the effect of chloride complex formation in solution and how strongly this complex formation is “extracting” heavy metal cation from soil and sediments substrates. As experimental data for speciation at very high ionic strength is not readily available and not easily measurable, we focus on PHREEQC modelling to assess NaCl concentration ranges up to 3 M, needing to employ Pitzer equation as the activity model. In order to determine the competition of surface reaction and complex formation in aqueous solution, we used three reaction models: i) surface complexation with a high and low affinity site for iron hydroxide, ii) a heterogeneous binding site model for humic acids and iii) ion exchange as described with Rothmund-Kornfeld equation We did a series of simulations for Zn, Cd and Pb. Species distribution for the aqueous phase and the solid surfaces where determined by increasing NaCl solutions for a given total heavy metal concentration. In nearly all simulations conducted, the difference between simulations allowing chloride complexes to form and simulations where complexation is disabled, showed the emergence of a characteristic concentration range of NaCl for which the effect of chloride complexation reaches a maximum. In general, the range of highest sensitivity concerning mobilization occurs within the range of 1-3M NaCl for all simulations. At the lower end of this range shows the highest sensitivity to NaCl changes and is determined by several factors including the affinity to bonding sites and the speciation of an element along the salinity gradient. The peak of this curve is controlled by the point along the salinity gradient where the majority of heavy metal has been mobilized from the surface phase. One important outcome of this study is, that increasing NaCl background concentration behaves in a nonlinear way that is determined by the heterogeneity of the surface binding sites and that there is no simple way of assessing the mobilization potential of chloride complexation in soils and sediments. Y1 - 2019 UR - https://meetingorganizer.copernicus.org/EGU2019/EGU2019-17360.pdf CY - Katlenburg-Lindau ER - TY - GEN A1 - Kuhn, Ramona A1 - Jensch, Robert A1 - Bryant, Isaac Mbir A1 - Fischer, Thomas A1 - Liebsch, Stephan A1 - Martienssen, Marion T1 - Rapid sample clean-up procedure for aminophosphonate determination by LC/MS analysis T2 - Talanta N2 - Aminophosphonates are commonly utilised for complexing bivalent ions such as calcium and magnesium. With regard to environmental samples, the analysis of these highly polar compounds is still challenging due to matrix effects and lacking analytical standard methods. We have recently developed a LC/MS method for common aminophosphonates without derivatisation. This LC/MS method delivers precise and accurate measurement for standard samples with very low concentration of cations disturbing the analysis. However, due to matrix effects this LC/MS method requires a sample clean-up being also applicable to natural water or wastewater samples. We developed and optimised a sample clean-up procedure applying strong cation exchange resin Dowex 50WX8. This clean-up allows a single LC/MS analysis of hydroxyethelidene(diphosphonic acid) (HEDP), aminotris(methylenephosphonic acid) (ATMP), ethylenediaminetetra(methyloenephosphonic acid) (EDTMP), diethylenetriaminepenta(methylenephosphonic acid) (DTPMP) and its major intermediates amino(methylphosphonic acid) (AMPA) and iminodi(methylenephosphonic acid) (IDMP). We compared different test conditions with six aminophosphonates in either ultra pure water or tap water. The latter was used to simulate cation concentrations typical for natural waters. To elute all aminophosphonate including AMPA, ammonium acetate addition was necessary. The addition of ammonium acetate was combinable with all tested aminophosphonates and provides high sample quality for LC/MS analysis. For acceptable recovery, the smallest aminophosphonate AMPA required the highest addition of ammonium acetate (1000 mg L-1) during the sample clean-up. Finally, the optimised clean-up procedure was successfully applied to identify and quantify phosphonates from an industrial wastewater sample. The sample clean-up procedure is simple, cheap, rapid and precise and can be further combined with solid phase extraction and more sensitive LC/MS methods. KW - Phosphontes Y1 - 2019 U6 - https://doi.org/10.1016/j.talanta.2019.120454 SN - 0039-9140 VL - 208 ER - TY - GEN A1 - Wanner, Manfred A1 - Birkhofer, Klaus A1 - Fischer, Thomas A1 - Shimizu, Miki A1 - Shimano, Satoshi D. A1 - Puppe, Daniel T1 - Soil Testate Amoebae and Diatoms as Bioindicators of an Old Heavy Metal Contaminated Floodplain in Japan T2 - Microbial Ecology Y1 - 2020 U6 - https://doi.org/10.1007/s00248-019- 01383-x SN - 1432-184X SN - 0095-3628 VL - 79 IS - 1 SP - 123 EP - 133 ER - TY - GEN A1 - Kuhn, Ramona A1 - Jensch, Robert A1 - Bryant, Isaac Mbir A1 - Fischer, Thomas A1 - Liebsch, Stephan A1 - Martienssen, Marion T1 - Photodegradation of ethylenediaminetetra(methylenephosphonic acid) – The effect of the system configuration T2 - Journal of Photochemistry & Photobiology A: Chemistry N2 - Photodegradation of aminophosphonates such as ethylenediaminetetra(methylenephosphonic acid) (EDTMP) is recently assumed being the major degradation pathway in aquatic environments. Several photolysis studies were reported about EDTMP and possible breakdown products occurring in natural ecosystems. Reliable prediction of environmental photolysis of parent compounds and possible release of breakdown products requires different set-up conditions and varying the parameters influencing the photodegradation. We studied the influence of three different system configurations during UV degradation of EDTMP. These three configurations differed either in geometry and/or treated sample volumes. System 1 was equipped with a direct cooling jacket at the UV lamp. System 2 had the geometry of system 1 but there was no usage of a direct cooling jacket. System 3 was a gas-tight system with a larger sample volume. Using the chemical actinometer potassium ferrioxalate, we determined the highest photon flux for system 3 followed by system 2 and 1. In addition, we performed scavenger experiments with methanol and ascorbic acid in order to prove the dominating radical species. In system 1, the addition of methanol showed almost no effect while the ascorbic acid resulted in a reduction of 57.1% orthophosphate released. Therefore we conclude that in system 1 the radical-drive degradation of EDTMP is mainly based on superoxide radicals. In system 2 and 3 both radical species, i.e., hydroxyl radicals and superoxide radicals, contribute to the photodegradation of EDTMP. We determined different half-lives for EDTMP for the three different systems configurations. For system 1, the estimated half-life achieved was 14.09 ± 0.15 min. For system 2 and 3, the half-lives were almost similar and averaged 4.75 ± 0.05 min and 5.02 ± 0.20 min, respectively. Contrary to our assumption to also find the highest degradation rate for system 3, we found the highest degradation rate for system configuration 2 as a result of the differences in the construction and geometry of the three systems. Our findings lead us to recommend the three system configuration for different research purposes. Thus, we recommend system 1 for detailed studies on the degradation pathway of the parent compound and their breakdown products. System 2 is recommended as a suitable configuration for kinetic studies of the parent compound. And finally, we recommend the system configuration 3 for complete mass balances. The gas-tight system allows determining all soluble and gaseous compounds. KW - Phosphonates KW - Photodegradation KW - Photon flux KW - Scavenger KW - LC/MS KW - Actinometry Y1 - 2020 U6 - https://doi.org/10.1016/j.jphotochem.2019.112192 SN - 1010-6030 VL - 388 ER - TY - GEN A1 - Zhang, Tingyi A1 - Moreau, Danielle J. A1 - Geyer, Thomas A1 - Fischer, Jeoffrey A1 - Doolan, Con T1 - Dataset on tip vortex formation noise produced by wall-mounted finite airfoils with flat and rounded tip geometries T2 - Data in Brief Y1 - 2020 U6 - https://doi.org/10.1016/j.dib.2019.105058 SN - 2352-3409 VL - 28 ER - TY - GEN A1 - Zhang, Tingyi A1 - Moreau, Danielle J. A1 - Geyer, Thomas A1 - Fischer, Jeoffrey A1 - Doolan, Con T1 - Dataset on tip vortex formation noise produced by wall-mounted finite airfoils with sinusoidal and porous tip geometries T2 - Data in Brief Y1 - 2020 U6 - https://doi.org/10.1016/j.dib.2020.105471 SN - 2352-3409 VL - 30 ER - TY - GEN A1 - Schlykow, Viktoria A1 - Manganelli, Constanza Lucia A1 - Römer, Friedhard A1 - Clausen, Caterina J. A1 - Augel, Lion A1 - Schulze, Jörg A1 - Katzer, Jens A1 - Schubert, Michael Andreas A1 - Witzigmann, Bernd A1 - Schroeder, Thomas A1 - Capellini, Giovanni A1 - Fischer, Inga Anita T1 - Ge(Sn) nano-island/Si heterostructure photodetectors with plasmonic antennas T2 - Nanotechnology Y1 - 2020 U6 - https://doi.org/10.1088/1361-6528/ab91ef SN - 1361-6528 VL - 31 IS - 34 ER - TY - GEN A1 - Manzoni, Stefano A1 - Chakrawal, Arjun A1 - Fischer, Thomas A1 - Schimel, Joshua P. A1 - Porporato, Amilcare A1 - Vico, Giulia T1 - Rainfall intensification increases the contribution of rewetting pulses to soil respiration T2 - Biogeosciences N2 - Soil drying and wetting cycles promote carbon (C) release through large heterotrophic respiration pulses at rewetting, known as the “Birch” effect. Empirical evidence shows that drier conditions before rewetting and larger changes in soil moisture at rewetting cause larger respiration pulses. Because soil moisture varies in response to rainfall, these respiration pulses also depend on the random timing and intensity of precipitation. In addition to rewetting pulses, heterotrophic respiration continues during soil drying, eventually ceasing when soils are too dry to sustain microbial activity. The importance of respiration pulses in contributing to the overall soil heterotrophic respiration flux has been demonstrated empirically, but no theoretical investigation has so far evaluated how the relative contribution of these pulses may change along climatic gradients or as precipitation regimes shift in a given location. To fill this gap, we start by assuming that heterotrophic respiration rates during soil drying and pulses at rewetting can be treated as random variables dependent on soil moisture fluctuations, and we develop a stochastic model for soil heterotrophic respiration rates that analytically links the statistical properties of respiration to those of precipitation. Model results show that both the mean rewetting pulse respiration and the mean respiration during drying increase with increasing mean precipitation. However, the contribution of respiration pulses to the total heterotrophic respiration increases with decreasing precipitation frequency and to a lesser degree with decreasing precipitation depth, leading to an overall higher contribution of respiration pulses under future more intermittent and intense precipitation. Specifically, higher rainfall intermittency at constant total rainfall can increase the contribution of respiration pulses up to ∼10 % or 20 % of the total heterotrophic respiration in mineral and organic soils, respectively. Moreover, the variability of both components of soil heterotrophic respiration is also predicted to increase under these conditions. Therefore, with future more intermittent precipitation, respiration pulses and the associated nutrient release will intensify and become more variable, contributing more to soil biogeochemical cycling. Y1 - 2020 UR - https://bg.copernicus.org/articles/17/4007/2020/ U6 - https://doi.org/10.5194/bg-17-4007-2020 VL - 17 IS - 15 SP - 4007 EP - 4023 ER - TY - GEN A1 - Jurischka, Christoph A1 - Dinter, Franziska A1 - Efimova, Anastasia A1 - Weiss, Romano A1 - Schiebel, Juliane A1 - Schulz, Christian A1 - Fayziev, Bekzodjon A1 - Schierack, Peter A1 - Fischer, Thomas A1 - Rödiger, Stefan T1 - An explorative study of polymers for 3D printing of bioanalytical test systems T2 - Clinical Hemorheology and Microcirculation N2 - Background: The 3D printing is relevant as a manufacturing technology of functional models for forensic, pharmaceutical and bioanalytical applications such as drug delivery systems, sample preparation and point-of-care tests. Objective: Melting behavior and autofluorescence of materials are decisive for optimal printing and applicability of the product which are influenced by varying unknown additives. Methods: We have produced devices for bioanalytical applications from commercially available thermoplastic polymers using a melt-layer process. We characterized them by differential scanning calorimetry, fluorescence spectroscopy and functional assays (DNA capture assay, model for cell adhesion, bacterial adhesion and biofilm formation test). Results: From 14 tested colored, transparent and black materials we found only deep black acrylonitrile-butadiene-styrene (ABS) and some black polylactic acid (PLA) useable for fluorescence-based assays, with low autofluorescence only in the short-wave range of 300-400 nm. PLA was suitable for standard bioanalytical purposes due to a glass transition temperature of approximately 60°C, resistance to common laboratory chemicals and easy print processing. For temperature-critical methods, such as hybridization reactions up to 90°C, ABS was better suited. Conclusions: Autofluorescence was not a disadvantage per se but can also be used as a reference signal in assays. The rapid development of individual protocols for sample processing and analysis required the availability of a material with consistent quality over time. For fluorescence-based assays, the use of commercial standard materials did not seem to meet this requirement. KW - Thermal analysis KW - 3D Printing Y1 - 2020 UR - https://pubmed.ncbi.nlm.nih.gov/31929149/ U6 - https://doi.org/10.3233/CH-190713 SN - 1875-8622 VL - 75 IS - 1 SP - 57 EP - 84 ER - TY - GEN A1 - Krisponeit, Jon-Olaf A1 - Fischer, Simon A1 - Esser, Sven A1 - Moshnyaga, Vasily A1 - Schmidt, Thomas A1 - Piper, Louis F. J. A1 - Flege, Jan Ingo A1 - Falta, Jens T1 - The morphology of VO2/TiO2(001): terraces, facets, and cracks T2 - Scientific Reports N2 - Vanadium dioxide (VO2) features a pronounced, thermally-driven metal-to-insulator transition at 340 K. Employing epitaxial stress on rutile TiO2(001) substrates, the transition can be tuned to occur close to room temperature. Striving for applications in oxide-electronic devices, the lateral homogeneity of such samples must be considered as an important prerequisite for efforts towards miniaturization. Moreover, the preparation of smooth surfaces is crucial for vertically stacked devices and, hence, the design of functional interfaces. Here, the surface morphology of VO2/TiO2(001) films was analyzed by low-energy electron microscopy and diffraction as well as scanning probe microscopy. The formation of large terraces could be achieved under temperature-induced annealing, but also the occurrence of facets was observed and characterized. Further, we report on quasi-periodic arrangements of crack defects which evolve due to thermal stress under cooling. While these might impair some applicational endeavours, they may also present crystallographically well-oriented nano-templates of bulk-like properties for advanced approaches. KW - Vanadium dioxide (VO2) KW - rutile TiO2(001) KW - metal-to-insulator transition KW - morphology KW - crystallography KW - low-energy electron microscopy (LEEM) KW - low-energy electron diffraction (LEED) KW - scanning probe microscopy Y1 - 2020 U6 - https://doi.org/10.1038/s41598-020-78584-9 SN - 2045-2322 VL - 10 ER - TY - GEN A1 - Zhang, Tingyi A1 - Geyer, Thomas A1 - Silva, Charitha de A1 - Fischer, Jeoffrey A1 - Doolan, Con A1 - Moreau, Danielle J. T1 - Experimental Investigation of Tip Vortex Formation Noise Produced by Wall-Mounted Finite Airfoils T2 - Journal of Aerospace Engineering Y1 - 2021 UR - https://ascelibrary.org/doi/10.1061/%28ASCE%29AS.1943-5525.0001315 U6 - https://doi.org/10.1061/(ASCE)AS.1943-5525.0001315 SN - 1943-5525 VL - 34 IS - 6 ER - TY - GEN A1 - Franzen, Christoph A1 - Fischer, Thomas T1 - Removal of Iron Crusts from Sandstone Sculptures in a Fountain T2 - Environmental Earth Sciences Y1 - 2022 U6 - https://doi.org/10.1007/s12665-022-10302-2 SN - 1866-6299 SN - 1866-6280 VL - 81 IS - 7 ER - TY - GEN A1 - Kuhn, Ramona A1 - Jensch, Robert A1 - Fischer, Thomas A1 - Keuler, Klaus A1 - Bryant, Isaac Mbir A1 - Martienssen, Marion T1 - Sunlight Degradation of the Aminophosphonate Diethylenetriamine Penta-(Methylenephosphonic Acid) T2 - Solar N2 - Aminophosphonate diethylenetriamine penta(methylenephosphonic acid) (DTPMP) is a scale inhibitor commonly used in several industries. DTPMP is suspected to cause anthropogenic pollution through discharge into the aquatic environment. DTPMP is assumed to be degraded by sunlight radiation. We recently predicted a preliminary degradation pathway of DTPMP applyingUV treatment. Currently, we have not yet evidenced that DTPMP shows the same degradation pattern with natural sunlight. One major reason leads to the fact that the light spectrum emitted by UV lamps does not completely represent the natural sunlight spectrum, and the emitted UVB and UVA irradiation flux is much higher than for solar light. For that reason, the degradation pattern and kinetics might be different between artificial UV treatment and natural sunlight treatment. Here, we investigated whether DTPMP is degradable under natural sunlight radiation, and whether the degradation mechanisms determined through UV treatment are transferable to sunlight. We investigated five different treatment conditions, i.e., DTPMP degradation in direct or diffuse sunlight, in diffuse sunlight with addition of Ca2+ or Mg2+, and in diffuse sunlight with local TW. Our experiment was carried out from March 2021 to October 2021. We performed LC/MS analyses and measured the release of o-PO4 3  . DTPMP was degraded with all five treatment conditions. The fastest DTPMP degradation occurred in direct and diffuse sunlight without addition of bivalent cations. The addition of Ca2+ and Mg2+ resulted in inhibited degradation. Similar effects occurred for sunlight treatment with local TW. We evidenced different degradation mechanisms for DTPMP depending on the presence of alkaline earth metals as we previously proposed for UV-treated DTPMP. However, both degradation mechanisms of DTPMP belong to the same degradation pathway determined with UV treatment. Therefore, we conclude that DTPMP undergoes a similar degradation pathway in sunlight as compared to UV light. KW - Photochemistry Y1 - 2022 U6 - https://doi.org/10.3390/solar2020009 SN - 2673-9941 VL - 2 IS - 2 SP - 141 EP - 157 ER - TY - GEN A1 - Kidron, Giora J. A1 - Fischer, Thomas A1 - Xiao, Bo T1 - The ambivalent effect of biocrusts on evaporation: Can the contradictory conclusions be explained? A review T2 - Geoderma Y1 - 2022 U6 - https://doi.org/10.1016/j.geoderma.2022.115805 SN - 1872-6259 VL - Vol. 416 ER - TY - GEN A1 - Kidron, Giora J. A1 - Lichner, Lubomir A1 - Fischer, Thomas A1 - Starinsky, Abraham A1 - Or, Dani T1 - Mechanisms for biocrust-modulated runoff generation – A review T2 - Earth-Science Reviews Y1 - 2022 UR - https://www.sciencedirect.com/science/article/abs/pii/S0012825222001842?via%3Dihub U6 - https://doi.org/10.1016/j.earscirev.2022.104100 SN - 0012-8252 SN - 1872-6828 VL - 231 SP - 1 EP - 22 ER - TY - GEN A1 - Fischer, Thomas A1 - Marchetti-Deschmann, Martina A1 - Assis, Ana Cristina A1 - Elad, Michal Levin A1 - Algarra, Manuel A1 - Barac, Marko A1 - Bogdanovic Radovic, Iva A1 - Cicconi, Flavio A1 - Claes, Britt A1 - Frascione, Nunzianda A1 - George, Sony A1 - Guedes, Alexandra A1 - Heaton, Cameron A1 - Heeren, Ron A1 - Lasic, Violeta A1 - Lerma, José Luis A1 - Valle Martinez de Yuso Garcia, Maria del A1 - Nosko, Martin A1 - O'Hara, John A1 - Oshina, Ilze A1 - Palucci, Antonio A1 - Pawlaczyk, Aleksandra A1 - Pospíšková, Kristýna A1 - de Puit, Marcel A1 - Radodic, Ksenija A1 - Rēpele, Māra A1 - Ristova, Mimoza A1 - Romolo, Francesco Saverio A1 - Šafařík, Ivo A1 - Siketic, Zdravko A1 - Spigulis, Janis A1 - Szynkowska-Jozwik, Malgorzata Iwona A1 - Tsiatsiuyeu, Andrei A1 - Vella, Joanna A1 - Dawson, Lorna A1 - Rödiger, Stefan A1 - Francese, Simona T1 - Profiling and imaging of forensic evidence – A pan-European forensic round robin study part 1: Document forgery T2 - Science & Justice Y1 - 2022 U6 - https://doi.org/10.1016/j.scijus.2022.06.001 SN - 1876-4452 SN - 1355-0306 VL - 62 IS - 4 SP - 433 EP - 447 ER - TY - GEN A1 - Becker, L. A1 - Storck, Peter A1 - Liu, Y. A1 - Schwalb, G. A1 - Schroeder, Thomas A1 - Fischer, Inga Anita A1 - Albrecht, M. T1 - Optimizing misfit dislocation glide kinetics for enhanced threading dislocation density reduction in Si1− xGex/Si (001) layers through dynamic growth rate control T2 - Journal of Applied Physics Y1 - 2024 U6 - https://doi.org/10.1063/5.0204318 SN - 0021-8979 SN - 1089-7550 VL - 135 IS - 20 SP - 10 ER - TY - GEN A1 - Eissa, Mohamed Hussein A1 - Fischer, Gunter A1 - Mausolf, Thomas A1 - Rücker, Holger A1 - Malignaggi, Andrea A1 - Kahmen, Gerhard T1 - 220-320-GHz J-Band 4-Way Power Amplifier in Advanced 130-nm BiCMOS Technology T2 - IEEE Microwave and Wireless Components Letters Y1 - 2022 U6 - https://doi.org/10.1109/LMWC.2022.3181407 SN - 1531-1309 SN - 1558-1764 VL - 32 IS - 11 SP - 1335 EP - 1338 ER - TY - GEN A1 - Fischer, Thomas A1 - Veste, Maik A1 - Wiehe, Wolfgang A1 - Lange, Philipp T1 - How biological crusts are stabilizing the soil surface? The development of organo-mineral interactions in the initial phase T2 - EGU General Assembly 2009, Vienna, Austria, 19 – 24 April 2009 Y1 - 2009 N1 - EGU2009-8635 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Fischer, Thomas A1 - Veste, Maik A1 - Wiehe, Wolfgang A1 - Lange, Philipp ED - Ukonmaanaho, Liisa ED - Nieminen, Tiina Maileena ED - Starr, Michael T1 - Linking microstructural and spectroscopic analysis of biological soil crusts - investigation of organo-mineral interactions T2 - 6th International Symposium on Ecosystem Behaviour BIOGEOMON 2009 Y1 - 2009 UR - http://www.metla.fi/julkaisut/workingpapers/2009/mwp128.pdf SN - 978-951-40-2177-0 SP - S. 412 PB - Finnish Forest Research Institut CY - Vantaa, Finland ER - TY - GEN A1 - Dümig, Alexander A1 - Veste, Maik A1 - Hagedorn, Frank A1 - Fischer, Thomas A1 - Lange, Philipp A1 - Spröte, Roland A1 - Kögel-Knabner, Ingrid T1 - Biological soil crusts on initial soils: organic carbon dynamics and chemistry under temperate climatic conditions T2 - Biogeosciences Discussion Y1 - 2012 SN - 1810-6285 VL - 10 IS - 1 SP - 851 EP - 894 ER - TY - GEN A1 - Dümig, Alexander A1 - Veste, Maik A1 - Hagedorn, Frank A1 - Fischer, Thomas A1 - Lange, Philipp A1 - Spröte, Roland A1 - Kögel-Knabner, Ingrid T1 - Organic matter from biological soil crusts induces the initial formation of sandy temperate soils T2 - Catena N2 - Different development stages of algae-dominated and moss-dominated biological soil crusts (BSCs) were sampled on a natural sand dune (b17 years old) and on an experimental sand dune (b8 years old) along a catena, including gradients of vegetation cover, location on the slope, as well as composition and thickness of BSC organisms in northeastern Germany. The accumulation of BSC-derived organic carbon (OC)was determined for bulk materials and fractions less than 63 μm. The OC composition was characterized by solid-state 13C NMR spectroscopy and the carbohydrate-C signature. 14C contents were determined to assess the origin and dynamics of OC. From the radiocarbon contents, two OC pools were differentiated: recent BSC-derived and lignite-derived “old” OC. Downward movement of OC into the underlying substratewas found only undermoss-dominated BSCs at the old sand dune. BSC-derived OC was mainly composed of carbohydrate-C and, to a lesser extent, alkyl C and N-alkyl C, with considerably higher contributions of alkyl C in the young dune, indicating differences in the composition of extracellular polymeric substances produced by the BSCs with age. This is consistent with higher proportions of water-soluble OC of moss-dominated BSCs at the old dune, which is leached in the underlying substrate and initiates soil formation. Because of the channeling effect of mosses, OC depth translocation along with suspended colloidal substances contribute to OC accumulation in substrates. Y1 - 2014 U6 - https://doi.org/10.1016/j.catena.2014.06.011 VL - 122 SP - 196 EP - 208 ER - TY - CHAP A1 - Kögel-Knabner, Ingrid A1 - Bens, Oliver A1 - Hüttl, Reinhard F. A1 - Fischer, Thomas A1 - Dümig, Alexander A1 - Spröte, Roland ED - Hüttl, Reinhard F. ED - Kögel-Knabner, Ingrid ED - Schulin, Rainer ED - Gerwin, Werner T1 - Project A3 – Initial stages of humus development T2 - Structures and processes of the initial ecosystem development phase in an artificial water catchment (Final report CRC/TR 38) Y1 - 2013 SP - 25 EP - 35 PB - BTU Forschungszentrum Landschaftsentwicklung und Bergbaulandschaften (FZLB) CY - Cottbus ER - TY - CHAP A1 - Spröte, Roland A1 - Fischer, Thomas A1 - Veste, Maik A1 - Wiehe, Wolfgang A1 - Lange, Philipp A1 - Hüttl, Reinhard F. T1 - Development of top soil on quaternary inland dunes - How important are microorganisms? T2 - Gletscher, Wasser, Mensch – quartärer Landschaftswandel im peribaltischen Raum, 35. Hauptversammlung der DEUQUA e.V., 12th Annual Conference of the INQUA PeriBaltic Working Group, 13.-17.9.2010., Greifswald Y1 - 2010 SP - 163 EP - 164 PB - Lehrstuhl Physische Geographie, Inst. für Geographie und Geologie der Univ. Greifswald CY - Greifswald ER - TY - GEN A1 - Fischer, Thomas A1 - Veste, Maik A1 - Bens, Oliver A1 - Hüttl, Reinhard F. T1 - Dew formation on the surface of biological soil crusts in central European sand ecosystems T2 - Biogeosciences discussions N2 - Dew formation was investigated in three developmental stages of biological soil crusts (BSC), which were collected along a catena of an inland dune and in the initial substrate. The Penman equation, which was developed for saturated surfaces, was modified for unsaturated surfaces and used for prediction of dewfall rates. The levels of surface saturation required for this approach were predicted using the water retention functions and the thicknesses of the BSCs. During a single event, dewfall increased with crust development from 0.08 kg m−2 for the initial substrate to 0.10, 0.20 and 0.25 kg m−2 for crusts stages 1 to 3, respectively, which was well reflected by the model response. The suggested mechanism of dew formation involves a delay in water saturation in near-surface soil pores and EPS where the crusts were thicker and where the water capacity was high, resulting in elevated vapor flux towards the surface. The results also indicate that the amount of dewfall was too low to observe water flow into deeper soil. Analysis of the soil water retention curves revealed that, despite the sandy mineral matrix, moist crusts with clogged by swollen EPS pores exhibited a clay-like behavior. It is hypothesized that BSCs gain double benefit from suppressing their competitors by runoff generation and from improving their water supply by dew collection. Despite higher amounts of dew, the water availability to the crust community decreases with crust development, which may be compensated by ecophysiological adaptation of crust organisms, and which may further suppress higher vegetation or mosses. Y1 - 2012 U6 - https://doi.org/10.5194/bgd-9-8075-2012 VL - 9 SP - 8075 EP - 8092 ER - TY - GEN A1 - Zyakun, Anatoly A1 - Nii-Annang, Seth A1 - Franke, Gabriele A1 - Fischer, Thomas A1 - Buegger, Franz A1 - Dilly, Oliver T1 - Microbial Actvity and 13C/12C Ratio as Evidence of N-Hexadecane and N-Hexadecanoic Acid Biodegradation in Agricultural and Forest Soils T2 - Geomicrobiology Journal N2 - The dynamics of microbial degradation of exogenous contaminants, n-hexadecane and its primary microbial oxidized metabolite, n-hexadecanoic (palmitic) acid, was studied for topsoils, under agricultural management and beech forest on the basis the changes in O2 uptake, CO2 evolution and its associated microbial and non-microbial carbon isotopic signature, the respiratory quotient (RQ) and the priming effect (PE) of substrates. Soil microbial communities in agricultural soil responded to the n-hexadecane addition more rapidly compared to those of forest soil, with lag-periods of about 23 ± 10 and 68 ± 13 hours, respectively. Insignificant difference in the lag-period duration was detected for agricultural (tlag = 30 ± 13 h) and forest (tlag = 30 ± 14 h) soils treated with n-hexadecanoic (palmitic) acid. These results demonstrate that the soil microbiota differed in metabolic activities for using n-hexadecane as a reductive hydrocarbon and n-hexadecanoic acid as a partly oxidized hydrocarbon. The corresponding δ13C of respired CO2 after the addition of the hydrocarbon contaminants to soils indicates a shift in microbial activity towards the consumption of exogenous substrates with a more complete degradation of n-hexadecane in the agricultural soil, for which some initial contents of hydrocarbons are inherent. It was reflected in the carbon isotope signature of microbial biomass. It is supposed that the observed deviation of RQ from theoretically calculated value under microbial substrate mineralization is determined by difference in the time (Δti) of registration of CO2 production and O2 consumption. Positive priming effect (PE) of n-hexadecane and negative PE of n-hexadecanoic (palmitic) acid were detected in agricultural and forest soils. It is suggested that positive PE of n-hexadecane is conditioned by the induction of microbial enzymes that perform hydroxylation/oxygenation of stable SOM compounds mineralized by soil microbiota to CO2. The microbial metabolism coupled with oxidative decarboxylation of n-hexadecanoic acid is considered as one of the most probable causes of the revealed negative PE value. Y1 - 2011 U6 - https://doi.org/10.1080/01490451.2010.489922 SN - 1521-0529 VL - 28 IS - 7 SP - 632 EP - 647 ER - TY - GEN A1 - Fischer, Thomas A1 - Gypser, Stella A1 - Subbotina, Maria A1 - Veste, Maik T1 - Synergic hydraulic and nutritional feedback mechanisms control surface patchiness of biological soil crusts on tertiary sands at a post-mining site T2 - Journal of Hydrology and Hydromechanics N2 - In a recultivation area located in Brandenburg, Germany, five types of biocrusts (initial BSC1, developed BSC2 and BSC3, mosses, lichens) and non-crusted mineral substrate were sampled on tertiary sand deposited in 1985- 1986 to investigate hydrologic interactions between crust patches. Crust biomass was lowest in the non-crusted substrate, increased to the initial BSC1 and peaked in the developed BSC2, BSC3, the lichens and the mosses. Water infiltration was highest on the substrate, and decreased to BSC2, BSC1 and BSC3. Non-metric multidimensional scaling revealed that the lichens and BSC3 were associated with water soluble nutrients and with pyrite weathering products, thus representing a high nutrient low hydraulic feedback mode. The mosses and BSC2 represented a low nutrient high hydraulic feedback mode. These feedback mechanisms were considered as synergic, consisting of run-off generating (low hydraulic) and run-on receiving (high hydraulic) BSC patches. Three scenarios for BSC succession were proposed. (1) Initial BSCs sealed the surface until they reached a successional stage (represented by BSC1) from which the development into either of the feedback modes was triggered, (2) initial heterogeneities of the mineral substrate controlled the development of the feedback mode, and (3) complex interactions between lichens and mosses occurred at later stages of system development. Y1 - 2014 U6 - https://doi.org/10.2478/johh-2014-0038 SN - 0042-790X VL - 62 IS - 4 SP - 293 EP - 302 ER - TY - CHAP A1 - Fischer, Thomas A1 - Bergmann, Charlotte A1 - Hüttl, Reinhard F. ED - Hüttl, Reinhard F. ED - Bellmann, Klaus ED - Seiler, Wolfgang T1 - Auswirkungen sich zeitlich ändernder Schadstoffdepositionen auf Prozesse des Kohlenstoff- und Stickstoffumsatzes im Boden T2 - Atmosphärensanierung und Waldökosysteme Y1 - 1995 SN - 3-89367-053-X SP - 144 EP - 160 PB - Eberhard-Blottner-Verlag CY - Taunusstein ER - TY - GEN A1 - Fischer, Thomas A1 - Kholiavko, Tatiana A1 - Schaaf, Wolfgang A1 - Veste, Maik T1 - Soil respiration responses of moss and lichen biocoenoses to moderate and severe rain events after summer drought in a temperate early-successional ecosystem T2 - Ecohydrology N2 - It is commonly accepted that CO2 efflux increases with soil water content in aerated soils and that rewetting after periods of soil drying can result in respiration pulses. It has further been shown that soil pores may become water logged which can impede soil gas exchange. The present study aimed to quantify the carbon response of moss (Polytrichum piliferum) and lichen (Cladonia coniocraea) biocoenoses to different quantities of rain in an artificial catchment, which granted that the starting point of the development of both biocoenoses was the same. To address this aim, we conducted in situ soil moisture and soil respiration measurements, where soil respiration was hypothesised to emerge from a cryptogamic vegetation layer and from mineral soil beneath. We found that higher water-holding capacity of the moss layer and higher accumulation of organic matter in the upper mineral soil under mosses result in higher amounts of water stored near the surface. As a consequence, evaporation of water as well as pulses of CO2 efflux after moderate rain following a period of drought were higher in the moss biocoenosis, where the upper mineral soil was of key importance. In contrast, the lichen biocoenosis facilitated penetration of rainwater into the deep soil. Superimposing rewetting pulses, near-saturation of soil pores with water after severe rain resulted in gas exchange inhibition and diminished soil respiration until subsequent aeration in both biocoenoses KW - biocrusts KW - Hühnerwasser KW - respiration KW - soils Y1 - 2023 U6 - https://doi.org/10.1002/eco.2578 SN - 1936-0592 VL - 16 IS - 7 ER - TY - GEN A1 - Gypser, Stella A1 - Herppich, Werner B. A1 - Fischer, Thomas A1 - Lange, Philipp A1 - Veste, Maik T1 - Photosynthetic characteristics and their spatial variance on biological soil crusts covering initial soils of post-mining sites in Lower Lusatia, NE Germany T2 - Flora N2 - Following surface disturbance, quaternary sands are the basic substrate for soil development in the Lusatian reclamation area. These substrates mostly contain few organic matter and, hence, are nutrient poor. Accumulation of soil carbon is an important factor for ecosystem development, where biological soil crusts initially influence soil processes and promote ecosystem succession. The compositional structures of biological soil crusts at various developmental stages and their photosynthetic properties were investigated on two former open-cast lignite sites, currently under reclamation, an artificial sand dune in Welzow Süd, and a forest plantation in Schlabendorf Süd (Brandenburg, Germany). As development of biological soil crusts progressed, their contents of organic carbon and total chlorophyll increased. The ratio of these parameters, however, varied with the relative contribution of lichens and mosses in particular. Also maximum photochemical efficiency, net photosynthesis and respiration increased with crustal development. An additional evaluation of NDVI and chlorophyll fluorescence images showed that especially moss-dominated biocrusts had higher photosynthetic capacity compared to green algae-dominated biocrusts or soil lichens, so the photosynthetic capacity showed to be highly species-specific. The ratio of gross photosynthesis to respiration indicated a higher ecological efficiency of biocrusts dominated by green algae than of lichen-dominated biocrusts. The occurrence of soil lichens reduced net CO2 fixation and increased CO2 release due to the enhanced mycobiontic respiration. During crustal succession, the rise of photosynthesis-related parameters is not necessarily linear as a result of the highly heterogenic distribution of the different crustal organisms between biocrusts of similar developmental stages as well as between those growing at the two study sites. Therefore, the evaluation of relevant ecophysiological parameters highlighted that not all biocrust-forming organisms similarly contribute to the ecophysiological behavior of biological soil crusts. Nevertheless, the occurrence of the biological soil crusts promoted soil formation and accumulation of soil carbon in initial soils. Y1 - 2016 U6 - https://doi.org/10.1016/j.flora.2016.02.012 SN - 0367-2530 VL - Vol. 220 SP - 103 EP - 116 ER - TY - GEN A1 - Gypser, Stella A1 - Veste, Maik A1 - Fischer, Thomas A1 - Lange, Philipp T1 - Infiltration and water retention of biological soil crusts on reclaimed soils of former open-cast lignite mining sites in Brandenburg, north-east Germany T2 - Journal of hydrology and hydromechanics N2 - Investigations were done on two former open-cast lignite mining sites under reclamation, an artificial sand dune in Welzow Süd, and a forest plantation in Schlabendorf Süd (Brandenburg, Germany). The aim was to associate the topsoil hydrological characteristics of green algae dominated as well as moss and soil lichen dominated biological soil crusts during crustal succession with their water retention and the repellency index on sandy soils under temperate cli-mate and different reliefs. The investigation of the repellency index showed on the one hand an increase due to the cross-linking of sand parti-cles by green algae which resulted in clogging of pores. On the other hand, the occurrence of moss plants led to a de-crease of the repellency index due to absorption caused by bryophytes. The determination of the water retention curves showed an increase of the water holding capacity, especially in conjunction with the growth of green algae layer. The pore-related van Genuchten parameter indicate a clay-like behaviour of the developed soil crusts. Because of the inho-mogeneous distribution of lichens and mosses as well as the varying thickness of green algae layers, the water retention differed between the study sites and between samples of similar developmental stages. However, similar tendencies of water retention and water repellency related to the soil crust formation were observed. Biological soil crusts should be considered after disturbances in the context of reclamation measures, because the ini-tial development of green algae biocrusts lead to an increasing repellency index, while the occurrence of mosses and a gain in organic matter enhance the water holding capacity. Thus, the succession of biocrusts and their small-scale succes-sion promote the development of soil and ecosystem. Y1 - 2016 U6 - https://doi.org/10.1515/johh-2016-0009 VL - 64 IS - 1 SP - 1 EP - 11 ER - TY - GEN A1 - Gypser, Stella A1 - Veste, Maik A1 - Fischer, Thomas A1 - Lange, Philipp T1 - Formation of soil lichen crusts at reclaimed post-mining sites, Lower Lusatia, North-east Germany T2 - Graphis Scripta N2 - Biological soil crusts were investigated at reclaimed post-mining sites near Welzow and Schlabendorf in Lower Lusatia (Brandenburg, Germany). Various development stages from initial biological soil crusts built up by green algae, to more developed soil crusts with mosses, as well as moss-soil lichen crusts, were classified. The spatial-temporal dynamics during the development resulted in a moss-lichens cover with discrete patches of pioneer organisms like green algae in between. At the study sites, 13 species of terricolous lichens were identified. The formation of the biological soil crust is important for the accumulation of soil organic matter in the first millimeters of the topsoil of these pioneer ecosystems. A correlation between cryptogamic biomass and soil carbon content were found. Y1 - 2015 SN - 0901-7593 VL - 27 IS - 1-2 SP - 3 EP - 14 ER - TY - GEN A1 - Fischer, Thomas A1 - Veste, Maik T1 - Carbon cycling of biological soil crusts mirrors ecological maturity along a Central European inland dune catena T2 - Catena N2 - Photosynthesis and respiration of biological soil crusts (BSCs) sampled along a mobile inland dune catena were determined to evaluate the applicability of Odum’s P/R ratio, determined under controlled conditions, for estimation of ecosystem maturity. The theory is that in the early stages of ecological succession, the total photosynthesis (P) exceeds the rate of community respiration (R), so that the P/R ratio is greater than 1, and that P/R approaches 1 as succession occurs. In the special case of organic pollution, the P/R ratio is typically less than 1. Samples were collected in the deflation zone of the dune near the crest (BSC1, thickness 2-3 mm), at the lee side of grass tussocks at the slope (BSC2, thickness 2-4 mm) and near the base (BSC3, thickness 4-6 mm). Non crusted sand was used as control (BSC0). Photosynthesis, respiration, crust biomass, as well as fossil and allochthonous pedogenic carbon entering the system with mineral substrate were determined. The respiration of the BSC1 was dominated by the degradation of allochthonous organic matter, leading to a diminished P/R ratio. The better developed BSC2 and BSC3 were less influenced by allochthonous organic matter, where BSC maturity increased downslope with biomass increase. No significant relation between the P/R ratio and soil water tension was found. Crust carbon pools increased and flows intensified, but mineralization constants decreased with system maturation. It was concluded that Odum’s P/R ratio and accumulation of recalcitrant to biodegradation organic matter are indicative for biocrust maturity. Y1 - 2018 U6 - https://doi.org/10.1016/j.catena.2017.09.004 SN - 0341-8162 VL - 160 SP - 68 EP - 75 ER - TY - GEN A1 - Hüttl, Reinhard F. A1 - Fischer, Thomas T1 - Carbon sequestration and landscape ecology in Western Europe – editorial T2 - Ecological Engineering Y1 - 2007 U6 - https://doi.org/10.1016/j.ecoleng.2006.10.001 SN - 0925-8574 VL - 29 IS - 4 SP - 317 EP - 318 ER - TY - GEN A1 - Fischer, Thomas A1 - Veste, Maik A1 - Eisele, Andreas A1 - Bens, Oliver A1 - Spyra, Wolfgang A1 - Hüttl, Reinhard F. T1 - Small Scale Spatial Heterogeneity of Normalized Difference Vegetation Indices (NDVI) and Hot Spots of Photosynthesis in Biological Soil Crusts T2 - Flora N2 - Normalized Difference Vegetation Indices (NDVIs) are typically determined using satellite or airborne remote sensing, or field portable spectrometers, which give an averaged signal on centimetre to metre scale plots. Biological soil crust (BSC) patches may have smaller sizes, and ecophysiological, hydrological as well as pedological processes may be heterogeneously distributed within this level of resolution. A ground-based NDVI imaging procedure using low-cost equipment (Olympus Camedia 5000z digital camera equipped with a Hoya R72 infrared filter) was developed in this study to fill this gap at the level of field research, where carrying costly and bulky equipment to remote locations is often the limiting factor for data collection. Method principle and field data are presented, and the field experiment was deepened comparing NDVI measurements and CO2 turnover of soil crust samples in the laboratory, backing the reliability of the approach. A commercially available colour rendition chart with known red (600–700 nm) and NIR (800–900 nm) reflectances was placed into each scene and used for calibration purposes on a per-image basis. Generation of NDVI images involved (i) determination of red and NIR reflectances from the pixel values of the red and NIR channels, respectively, and (ii) calculation and imaging of the NDVI, where NDVI values of −1 to +1 were mapped to grey values of 0 to 255. The correlation between NDVI values retrieved from these images and NDVI values determined using field spectrometry was close (r2 = 0.91), the 95% confidence interval amounted to 0.10 NDVI units. The pixel resolution was 0.8 mm in the field and 0.2 mm in the laboratory, but can still be improved significantly with closer distance to the crust or with higher camera resolution. NDVI values obtained using the new method were related to the net CO2 uptake of BSCs, where both slope and correlation coefficient of the respective regression function conformed with literature data. Geostatistical analysis revealed that both spatial variability of net CO2 uptake as well as size of individual hot spots of this parameter increased with crust development. The latter never exceeded 4 mm in the investigated crusts, which points to the necessity of high resolution imaging for linking remote sensing with ecophysiology. Perspectively, the new method could be used for field monitoring of both biological soil crusts and vascular vegetation. Y1 - 2012 U6 - https://doi.org/10.1016/j.flora.2012.01.001 VL - 207 IS - 3 SP - 159 EP - 167 ER - TY - GEN A1 - Fischer, Thomas A1 - Veste, Maik A1 - Schaaf, Wolfgang A1 - Dümig, Alexander A1 - Kögel-Knabner, Ingrid A1 - Wiehe, Wolfgang A1 - Bens, Oliver A1 - Hüttl, Reinhard F. T1 - Initial pedogenesis in a topsoil crust 3 years after construction of an artificial water catchment in Brandenburg, NE Germany T2 - Biogeochemistry N2 - Cyanobacteria and green algae present in biological soil crusts are able to colonize mineral substrates even under extreme environmental conditions. As pioneer organisms, they play a key role during the first phases of habitat colonization. A characteristic crust was sampled 3 years after installation of the artificial water catchment “Chicken creek”, thus representing an early successional stage of ecosystem development. Mean annual rainfall and temperature were 559 mm and 9.3°C, respectively. We combined scanning electron microscopy (SEM/EDX) and infrared (FTIR) microscopy to study the contact zone of algal and cyanobacterial mucilage with soil minerals in an undisturbed biological soil crust and in the subjacent sandy substrate. The crust was characterized by an approximately 50 μm thick surface layer, where microorganisms resided and where mineral deposition was trapped, and by an approximately 2.5 mm thick lower crust where mineral particles were stabilized by organo-mineral structures. SEM/EDX microscopy was used to determine the spatial distribution of elements, organic compounds and minerals were identified using FTIR microscopy and X-ray diffraction (XRD). The concentration of organic carbon in the crust was about twice as much as in the parent material. Depletion of Fe, Al and Mn in the lower crust and in the subjacent 5 mm compared to the geological substrate was observed. This could be interpreted as the initial phase of podzolization. Existence of bridging structures between mineral particles of the lower crust, containing phyllosilicates, Fe compounds and organic matter (OM), may indicate the formation of organo-mineral associations. pH decreased from 8.1 in the original substrate to 5.1 on the crust surface 3 years after construction, pointing to rapid weathering of carbonates. Weathering of silicates could not be detected. Y1 - 2010 U6 - https://doi.org/10.1007/s10533-010-9464-z SN - 1573-515X VL - 101 IS - 1-3 SP - 165 EP - 176 ER - TY - GEN A1 - Dilly, Oliver A1 - Nii-Annang, Seth A1 - Franke, Gabriele A1 - Fischer, Thomas A1 - Buegger, Franz A1 - Zyakun, Anatoly T1 - Resilience of microbial respiration, respiratory quotient and stable isotope characteristics to soil hydrocarbon addition T2 - Soil Biology and Biochemistry N2 - On the basis of CO2 evolution rate, O2 uptake rate, and 13C isotopic signature of respired CO2, the metabolic response to the addition of 13C labelled n-hexadecane and palmitic acid each with supplementary nitrogen was studied for two topsoils, one under continuous agricultural management and the other under beech forest. The CO2 evolution rate was immediately stimulated in the agricultural soil and the respiratory quotient (RQ) decreased from 0.8 to 0.4 mol CO2 evolution rate per mol O2 uptake rate, which was below the theoretically expected value of 0.65 and 0.70 for the degradation of n-hexadecane and palmitic acid, respectively. The microbial response was delayed in the forest soil, but developed better than in the agricultural soil throughout the subsequent 2–4 weeks. Consequently, the respiration rate returned earlier to the initial level for the beech forest soil and the δ13C of respired CO2 and RQ approached values before hydrocarbon addition. Based on the link among respiration rates, RQ and 13C–CO2 value, the added oil-analogue compounds induced a more rapid response in the agricultural soil and were degraded more completely in the forest soil. We concluded that the resilience, which we defined here as the capacity of the soil microbiota to buffer perturbance and to reorganise in response to change resulting in a more desirable system, was higher in our forest soil than for the agricultural soil. Y1 - 2011 U6 - https://doi.org/10.1016/j.soilbio.2010.09.026 SN - 0038-0717 VL - 43 IS - 9 SP - 1808 EP - 1811 ER - TY - CHAP A1 - Bergmann, Charlotte A1 - Fischer, Thomas A1 - Hüttl, Reinhard F. ED - Hüttl, Reinhard F. ED - Bellmann, Klaus T1 - Decomposition of needle-, herb- and root- litter and Of-layer humus in three scots pine stands T2 - Changes of atmospheric chemistry and effects on forest ecosystems: A roof experiment without roof. Y1 - 1998 SN - 0-7923-5713-2 SP - 151 EP - 176 PB - Kluwer Academic Publishers CY - Dordrecht ER - TY - CHAP A1 - Bergmann, Charlotte A1 - Fischer, Thomas A1 - Hüttl, Reinhard F. ED - Hüttl, Reinhard F. ED - Bellmann, Klaus T1 - Seasonal variability of organic matter and N input with litterfall in three scots pine stands T2 - Changes of atmospheric chemistry and effects on forest ecosystems: A roof experiment without roof Y1 - 1998 SN - 0-7923-5713-2 SP - 177 EP - 186 PB - Kluwer Academic Publishers CY - Dordrecht ER -