TY - GEN A1 - Fischer, Thomas A1 - Bergmann, Charlotte A1 - Hüttl, Reinhard F. T1 - Soil carbon and nitrogen budget in Scots pine (Pinus sylvestris L) stands along an air pollution gradient in Eastern Germany Y1 - 1995 ER - TY - GEN A1 - Bergmann, Charlotte A1 - Fischer, Thomas A1 - Hüttl, Reinhard F. T1 - Significance of litter- and humus-layer quality for rates and forms of N cycling in moder- to rawhumus-moder profiles under Scots pine (Pinus sylvestris L.) Y1 - 1999 ER - TY - GEN A1 - Fischer, Thomas T1 - Substantial rewetting phenomena on soil respiration can be observed at low water availability Y1 - 2009 ER - TY - GEN A1 - Spröte, Roland A1 - Fischer, Thomas A1 - Veste, Maik A1 - Raab, Thomas A1 - Wiehe, Wolfgang A1 - Lange, Philipp A1 - Bens, Oliver A1 - Hüttl, Reinhard F. T1 - Biological topsoil crusts at early successional stages on recultivated post-mining sites in Brandenburg, NE Germany Y1 - 2010 ER - TY - GEN A1 - Fischer, Thomas A1 - Veste, Maik A1 - Wiehe, Wolfgang A1 - Lange, Philipp T1 - Water repellency and pore clogging at early successional stages of microbiotic crusts on inland dunes, Brandenburg, NE Germany Y1 - 2010 ER - TY - CHAP A1 - Fischer, Thomas T1 - Following chemical changes of Scots pine (Pinus sylvestris L.) root litter during decomposition using FTIR T2 - Woody root processes – Impact of different tree species, University of Tartu, Estonia, 05-09 June 2005 Y1 - 2005 SN - 9949-11-079-3 SP - 21 PB - Tartu University Press CY - Tartu ER - TY - GEN A1 - Fischer, Thomas T1 - Einfluß ausgewählter Fruchtfolgen und Fruchtarten auf die Kohlenstoffdynamik des Bodens auf einem grundwasserfernen Sandstandort T2 - Mitteilungen der Gesellschaft für Pflanzenbauwissenschaften Y1 - 1991 SN - 0934-5116 VL - 4 SP - 339 EP - 342 ER - TY - GEN A1 - Fischer, Thomas T1 - Einfluß von Winterweizen und Winterroggen in Fruchtfolgen mit unterschiedlichem Getreideanteil auf die mikrobielle Biomasse und die jahreszeitliche Kohlenstoffdynamik des Bodens T2 - Archiv für Acker- und Pflanzenbau und Bodenkunde Y1 - 1993 SN - 0365-0340 VL - 37 SP - 181 EP - 189 ER - TY - CHAP A1 - Fischer, Thomas ED - Merbach, Wolfgang T1 - Auswirkungen einer Wiederbefeuchtung auf die C- und N-Mineralisierung in der Humusauflage von Kiefernökosystemen T2 - Pflanzliche Stoffaufnahme und mikrobielle Wechselwirkungen in der Rhizosphere Y1 - 1996 SN - 3-8154-3528-5 SP - 13 EP - 20 PB - Teubner CY - Stuttgart [u.a.] ER - TY - GEN A1 - Fischer, Thomas A1 - Yair, Aaron A1 - Veste, Maik T1 - Microstructure and hydraulic properties of biological soil crusts on sand dunes: a comparison between arid and temperate climates T2 - Biogeosciences Discuss N2 - We studied the relationships between crust microstructure, infiltration and water holding capacity under arid and temperate conditions (Factor A: Climate) on biological soil crusts (BSCs) sampled along a catena on mobile sand dunes (Factor B: Catena). The arid study site was located near Nizzana, Israel (precipitation: 86mm a−1, PET: ca. 2500mm a−1) and the temperate site near Lieberose, Germany (precipitation: 569mm a−1, PET: ca. 780mm a−1). BSCs were sampled near the dune crest, at the centre of the dune slope and at the dune base at each site. Scanning electron microscopy (SEM) was used to characterize BSC morphology and microstructure. Infiltration was determined using microinfiltrometry under controlled moisture conditions in the lab. Water holding capacities were determined after water saturation of the dry BSCs. Wettability of the crusts was characterized using a “repellency index”, which was calculated from water and ethanol sorptivities. Irrespective of the climate, an accumulation of fine particles in the BSCs was found, increasing along the catena from dune crest to dune base. Texture was finer and water holding capacities of the underlying substrate were higher at the arid site, whereas surface wettability was reduced at the temperate site. At both sites, BSCs caused extra water holding capacity compared to the substrate. Infiltration rates decreased along the catena and were generally lower at the dune slope and base of the arid site. A mechanism of crust stabilization is proposed where BSCs benefit from increased texture and biomass mediated water supply, and where the water supply to higher plants was limited due to alteration of physico-chemical surface properties under temperate conditions. Y1 - 2012 U6 - https://doi.org/10.5194/bgd-9-12711-2012 VL - 9 SP - 12711 EP - 12734 ER - TY - CHAP A1 - Fischer, Thomas A1 - Yair, Aaron A1 - Veste, Maik T1 - Infiltration, water holding capacity and growth patterns of biological soil crusts on sand dunes under arid and temperate climates T2 - EGU General Assembly 2012, held 22-27 April, 2012 in Vienna Y1 - 2012 N1 - EGU2012-5034 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - GEN A1 - Dolezych, Martina A1 - Fischer, Thomas A1 - Gröschke, Andreas T1 - Pinuxylon succiniferum (GOEPPERT) KRAEUSEL emend. DOLEZYCH - amberized wood from GOEPPERT T2 - Mauritiana Y1 - 2011 SN - 0233-173X VL - 22 SP - 43 EP - 60 ER - TY - CHAP A1 - Fischer, Thomas A1 - Veste, Maik T1 - Small scale spatial heterogeneity of biological soil crusts during initial ecosystem development T2 - Abstract Book of the 12th European Ecological Federation Congress, 25-29 September 2011, Avila, Spain Y1 - 2011 UR - http://www.desertconsult.de/abstracts/Veste_EEF2011_2.pdf SP - S. 250 ER - TY - CHAP A1 - Fischer, Thomas A1 - Veste, Maik T1 - Biological soil crusts on inland dunes in NE Germany: Can we link succession with hydrology? T2 - Book of Abstracts Workshop "Biological Soil Crusts in Ecosystems - their Diversity, Ecology, and Management", 22-25. August 2010, Zellingen-Retzbach, Germany Y1 - 2010 UR - http://www.desertconsult.de/abstracts/biocrusts3.pdf SP - S. 52 ER - TY - GEN A1 - Geppert, Helmut A1 - Fischer, Thomas T1 - CHROMATOGRAPHIE-Festphasenmikroextraktion von polaren Verbindungen T2 - Labor Praxis Y1 - 2009 SN - 0344-1733 VL - 33 IS - 1 SP - 46 EP - 47 ER - TY - CHAP A1 - Fischer, Thomas A1 - Veste, Maik A1 - Lange, Philipp A1 - Wiehe, Wolfgang T1 - How biological soil crusts are stabilizing the soil surface? The development of organo-mineral interactions in the initial phase T2 - EGU General Assembly 2009, held in Vienna, Austria, 19 – 24 April 2009 Y1 - 2009 UR - http://meetingorganizer.copernicus.org/EGU2009/EGU2009-8635.pdf N1 - EGU2009-8635 PB - European Geophysical Society CY - Katlenburg-Lindau 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 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 first field campaign (2–3 August 2011), dewfall increased from 0.042 kg m−2 for the initial sandy substrate to 0.058, 0.143 and 0.178 kg m−2 for crusts 1 to 3, respectively. During a second field campaign (17–18 August 2011), where dew formation was recorded in 1.5 to 2.75-h intervals after installation at 21:30 CEST, dewfall increased from 0.011 kg m−2 for the initial sandy substrate to 0.013, 0.028 and 0.055 kg m−2 for crusts 1 to 3, respectively. Dewfall rates remained on low levels for the substrate and for crust 1, and decreased overnight for crusts 2 and 3 (with crust 3 > crust 2 > crust 1 throughout the campaign). Dew formation 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 extracellular polymeric substances (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 saturate the BSCs and to observe water flow into deeper soil. Analysis of the soil water retention curves revealed that, despite the sandy mineral matrix, moist crusts 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/bg-9-4621-2012 SN - 1726-4189 VL - 9 SP - 4621 EP - 4628 ER - TY - GEN A1 - Brankatschk, Robert A1 - Fischer, Thomas A1 - Veste, Maik A1 - Zeyer, Josef T1 - Succession of N Cycling Processes in Biological Soil Crusts on a Central European Inland Dune T2 - FEMS Microbiology Ecology N2 - Biological soil crusts (BSCs) are microbial assemblages that occur worldwide and facilitate ecosystem development by nitrogen (N) and carbon accumulation. N turnover within BSC ecosystems has been intensively studied in the past; however, shifts in the N cycle during BSC development have not been previously investigated. Our aim was to characterise N cycle development first by the abundance of the corresponding functional genes (in brackets) and second by potential enzyme activities; we focussed on the four processes: N fixation (nifH), mineralisation as proteolysis and chitinolysis (chiA), nitrification (amoA) and denitrification (nosZ). We sampled from four phases of BSC development and from a reference located in the rooting zone of Corynephorus canescens, on an inland dune in Germany. BSC development was associated with increasing amounts of chlorophyll, organic carbon and N. Potential activities increased and were highest in developed BSCs. Similarly, the abundance of functional genes increased. We propose and discuss three stages of N process succession. First, the heterotrophic stage (mobile sand without BSCs) is dominated by mineralisation activity. Second, during the transition stage (initial BSCs), N accumulates, and potential nitrification and denitrification activity increases. Third, the developed stage (established BSCs and reference) is characterised by the dominance of nitrification. Y1 - 2013 U6 - https://doi.org/10.1111/j.1574-6941.2012.01459.x SN - 1574-6941 VL - 83 IS - 1 SP - 149 EP - 160 ER - TY - GEN A1 - Xiao, Bo A1 - Wang, Huifang A1 - Fan, Jun A1 - Fischer, Thomas A1 - Veste, Maik T1 - Biological soil crusts decrease soil temperature in summer and increase soil temperature in winter in semiarid environment T2 - Ecological Engineering N2 - In hot and wet conditions in summer, the biological soil crusts (BSCs) decreased soil temperature by up to 11.8 °C, 7.5 °C, 5.4 °C, and 3.2 °C at surface, 5 cm, 15 cm, and 30 cm, respectively; while in cold and dry conditions in winter the BSCs increased soil temperature by up to 1.2 °C, 1.2 °C, and 1.1 °C at 5 cm, 15 cm, and 30 cm, respectively. The daily mean soil temperatures of the BSCs in a whole year were averagely increased by 0.57 ± 0.04 °C, 0.31 ± 0.04 °C, and 0.22 ± 0.04 °C at 5 cm, 15 cm, and 30 cm, respectively. The effects of the BSCs on soil temperature were positively correlated with air temperature and soil moisture, and decreased with soil depth from surface to deep soil. We concluded that BSCs relieved the extreme hot and cold soil micro-environments in desert ecosystem to some extent. Therefore their effects on soil temperature are positive for improving water and nutrient availability and biological community structure, thus decreasing susceptibility to desertification. These results would be helpful for understanding the ecological and hydrological functions of BSCs in semiarid environment. Y1 - 2013 U6 - https://doi.org/10.1016/j.ecoleng.2013.06.009 SN - 0925-8574 VL - 58 SP - 52 EP - 56 ER - TY - GEN A1 - Fischer, Thomas A1 - Yair, Aaron A1 - Veste, Maik A1 - Geppert, Helmut T1 - Hydraulic properties of biological soil crusts on sand dunes studied by 13C-CP/MAS-NMR: a comparison between an arid and a temperate site T2 - Catena N2 - Using principal component analysis (PCA), we studied the relationships between hydraulic properties and 13C-CP/MAS-NMR shift regions of biological soil crusts (BSCs) on sand dunes under arid and temperate conditions. The arid study site was located near Nizzana, in the northwestern Negev, Israel and the temperate site was near Lieberose, Brandenburg, Germany. BSCs were sampled at each site near the dune crest, at the center of the dune slope and at the dune base. The soil texture was finer and water holding capacities (WHCs) were higher in Nizzana, whereas surface wettability was reduced in Lieberose. At both sites, BSCs caused extra WHC compared to the mineral substrate. Infiltration after wetting along both catenas generally reached a maximum after 10 min and decreased after 30 min. Carbohydrates were the dominating components in all of the BSCs studied, where the relative peak areas of carbohydrate-derived structures (60–110 ppm) amounted to 28–46% and to 10–14% of total C-peak areas, respectively. PCA revealed that the WHC of the substrate was closely related to the amount of silt and clay, whereas the BSC induced extra WHC was closely related to carbohydrates. It was further found that water repellency was positively related to carbohydrate C, but negatively related to alkyl C. Infiltration kinetics was attributed to polysaccharide hydration and swelling. Our findings support the hypothesis that hydraulic properties of BSCs are determined by extracellular polymeric substances (EPS) and soil texture. Hydraulic properties in BSCs result from the combination of chemical properties related to C compounds mainly dominated by carbohydrates and physical surface properties related to texture, porosity and water holding capacity. Y1 - 2013 U6 - https://doi.org/10.1016/j.catena.2013.06.002 SN - 0341-8162 VL - 110 SP - 155 EP - 160 ER - TY - CHAP A1 - Iurchenko, Valentina A1 - Mykhailova, Larysa A1 - Fischer, Thomas T1 - Kinetic Characteristics of Petrochemicals Transposition and Accumulation in Soils of Roadside Area T2 - Transbaltica 2013 Conference Proceedings, 09.-10. May 2013, Vilnius, Lithuania Y1 - 2013 U6 - https://doi.org/10.3846/transbaltica2013.016 ER - TY - GEN A1 - Mykhailova, Larysa A1 - Fischer, Thomas A1 - Iurchenko, Valentina T1 - Distribution and fractional composition of petroleum hydrocarbons in roadside soils T2 - Applied and Environmental Soil Science Y1 - 2013 U6 - https://doi.org/10.1155/2013/938703 VL - 2013 IS - ID 938703 SP - 1 EP - 6 ER - TY - GEN A1 - Wang, Haijing A1 - Geppert, Helmut A1 - Fischer, Thomas A1 - Wieprecht, Wolfgang A1 - Möller, Detlev T1 - Determination of volatile organic and polycyclic aromatic hydrocarbons in crude oil with efficient gas-chromatographic methods T2 - Journal of Chromatographic Science N2 - Determination of volatile organic compounds (VOCs) in crude oil, such as super volatile organic compounds (super VOCs) and simple polycyclic aromatic hydrocarbons (PAHs), is vital for targeting crude oil spill spots. In this study, a static headspace gas chromatography flame ionization detection method was established for determination of super VOCs in crude oil with both external and internal standard determination, which can be used in the field when using portable gas chromatography. Identification was done by comparing the retention time with the corresponding standards and quantitation was done with a new one-drop method. Another simplified and efficient method was performed to analyze volatile PAHs in crude oil, which can also be used in field analysis. Toluene was used as the extraction solvent for PAHs in crude oil. Method validation for both analyses was satisfactory. The result showed that n-butane and n-pentane were maximum super VOCs and naphthalene, phenanthrene and fluorene were the main PAHs in the crude oil studied. The super VOCs quantity ranged from 3 to 6% and the main PAHs consisted of 0.02–0.06% of studied crude oil. Y1 - 2014 U6 - https://doi.org/10.1093/chromsci/bmu113 SN - 1945-239X VL - 53 IS - 5 SP - 647 EP - 654 ER - TY - GEN A1 - Mykhailova, Larysa A1 - Fischer, Thomas A1 - Iurchenko, Valentina T1 - Deposition of petroleum hydrocarbons with sediment trapped in snow in roadside areas T2 - Journal of Environmental Engineering and Landscape Management N2 - Total petroleum hydrocarbon (TPH) deposition rates were determined along various roads using the natural snow cover as deposition trap. Daily deposition rates decreased with distance from the roads, which coincided with long-term TPH accumulation in roadside soils. Scanning electron microscopy (SEM-EDX) of the snow meltwater sediment revealed occurrence of carbon-rich plaques, which were identified as hydrocarbons using FTIR-microscopy. GC-MS revealed that the compounds extracted from the sediment consisted of an unresolved complex hydrocarbon mixture (UCM). Individual n-alkanes could not be resolved in the sediment extract, whereas TPHs extracted from soils contained a series of n-alkanes peaking at C25-C27. The proportion of UCM compounds from TPHs decreased with distance from road. We conclude that high-boiling hydrocarbons bind to coarse mineral dust and/or to splash water and vehicle spray, which preferentially deposit within a 10 m roadside strip. Y1 - 2014 U6 - https://doi.org/10.3846/16486897.2014.889698 SN - 1822-4199 VL - 22 IS - 3 SP - 237 EP - 244 ER - TY - CHAP A1 - Fischer, Thomas A1 - Veste, Maik A1 - Mykhailova, Larysa T1 - Ecological Maturity and Drought Stress of Biological Soil Crusts along a Central European Inland Dune Catena T2 - European Geosciences Union, General Assembly 2014, Vienna, Austria, 27 April – 02 May 2014 Y1 - 2014 N1 - EGU2014-11377 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Fischer, Thomas A1 - Yair, Aaron A1 - Geppert, Helmut A1 - Veste, Maik T1 - Water repellency and infiltration of biological soil crusts on an arid and a temperate dunes T2 - European Geosciences Union, General Assembly 2014, Vienna, Austria, 27 April – 02 May 2014 Y1 - 2014 N1 - EGU2014-12175 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Fischer, Thomas T1 - Initial pedogenesis in biological soil crusts T2 - Nasledie I. V. Tjurina v sovremennych issledovanijach v počvovedenii: materialy Meždunarodnoj naučnoj konferencii, Kazan', 15 - 17, oktjabrja 2013 Y1 - 2013 UR - http://kpfu.ru/docs/F928601744/Materialy.konferencii.Tjurina._1_.pdf SN - 978-5-9222-0726-3 SP - 19 EP - 21 PB - Izdat. Otečestvo CY - Kazan', Russian Federation ER - TY - GEN A1 - Wang, Haijing A1 - Fischer, Thomas A1 - Wieprecht, Wolfgang A1 - Möller, Detlev T1 - A predictive method for crude oil volatile organic compounds emission from soil: Evaporation and diffusion behavior investigation of binary gas mixtures T2 - Environmental Science and Pollution Research N2 - Due to their mobility and toxicity, crude oil volatile organic compounds (VOCs) are representative components for oil pipeline contaminated sites detection. Therefore, contaminated location risk assessment, with airborne light detection and ranging (LIDAR) survey, in particular, requires ground-based determinative methods for oil VOCs, the interaction between oil VOCs and soil, and information on how they diffuse from underground into atmosphere. First, we developed a method for determination of crude oil VOC binary mixtures (take n-pentane and n-hexane as examples), taking synergistic effects of VOC mixtures on polydimethylsiloxane (PDMS) solid-phase microextraction (SPME) fibers into consideration. Using this method, we further aim to extract VOCs from small volumes, for example, from soil pores, using a custom-made sampling device for nondestructive SPME fiber intrusion, and to study VOC transport through heterogeneous porous media. Second, specific surface Brunauer–Emmett–Teller (BET) analysis was conducted and used for estimation of VOC isotherm parameters in soil. Finally, two models were fitted for VOC emission prediction, and the results were compared to the experimental emission results. It was found that free diffusion mode worked well, and an empirical correction factor seems to be needed for the other model to adapt to our condition for single and binary systems. Y1 - 2015 U6 - https://doi.org/10.1007/s11356-014-4049-3 SN - 0944-1344 SN - 1614-7499 ER - TY - GEN A1 - Fischer, Thomas A1 - Subbotina, Maria T1 - Climatic and soil texture threshold values for cryptogamic cover development: a meta analysis T2 - Biologia N2 - In a global meta study, which contained 157 biological soil crust (BSC) samples from all climatic regions worldwide, climatic and soil texture threshold values favoring BSC development were derived. Response variable was the “relative crust biomass”, which was computed per literature source as the ratio between each individual crust biomass value of the given study to the study maximum value reported. Four crust types were distinguished: cyanobacterial, lichen, green algal and moss crusts. To quantify threshold conditions at which crust biomass responded to differences in texture and climate, we (I) determined correlations between bioclimatic variables, (II) calculated generalized linear models to determine the effect of typical climatic variables with soil clay content and with study site as a random effect. (III) Thresholds of climatic and texture effects were identified using a regression tree. Three mean annual temperature classes for texture dependent BSC growth limitation were identified: (1) <9°C with a threshold value of 25% silt and clay (limited growth on coarser soils), (2) 9–19°C, where texture did have no influence on relative crust biomass, and (3) >19°C at soils with <4 or >17% silt and clay. Non of the precipitation related bioclimatic variables did influence the relative crust biomass significantly. Because biocrust development is limited under certain climatic and soil texture conditions, it is suggested to consider soil texture in biogeochemical modeling of cryptogamic ground covers. Y1 - 2014 U6 - https://doi.org/10.2478/s11756-014-0464-7 SN - 1336-9563 SN - 0006-3088 VL - 69 IS - 11 SP - 1520 EP - 1530 ER - TY - CHAP A1 - Fischer, Thomas A1 - Gypser, Stella A1 - Subbotina, Maria A1 - Veste, Maik T1 - Hydraulic and nutritional feedback controls surface patchiness of biological soil crusts at a post-mining site T2 - European Geosciences Union, General Assembly 2015, Vienna, Austria, 13 April - 17 May 2015 Y1 - 2015 N1 - EGU2015-4551 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Mykhailova, Larysa A1 - Fischer, Thomas A1 - Iurchenko, Valentina T1 - Microbial activity and soil organic matter decay in roadside soils polluted with petroleum hydrocarbons T2 - European Geosciences Union, General Assembly 2015, Vienna, Austria, 13 April - 17 May 2015 Y1 - 2015 N1 - EGU2015-1728 PB - European Geophysical Society CY - Katlenburg-Lindau ER - 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 - Bonhage, Alexander A1 - Raab, Thomas A1 - Schneider, Anna A1 - Fischer, Thomas A1 - Ramezany, Shaghayegh A1 - Ouimet, William A1 - Raab, Alexandra A1 - Hirsch, Florian T1 - Vertical SOC distribution and aromatic carbon in centuries old charcoal-rich Technosols T2 - European Journal of Soil Science N2 - Charcoal-rich Technosols on century-old relict charcoal hearths (RCHs) are the subject of ongoing research regarding potential legacy effects that result from historic charcoal production and subsequent charcoal amendments on forest soil properties and forest ecosystems today. RCHs consist mostly of Auh horizons that are substantially enriched in soil organic carbon (SOC), of which the largest part seems to be of pyrogenic origin (PyC). However, the reported range of SOC and PyC contents in RCH soil also suggests that they are enriched in nonpyrogenic SOC. RCH soils are discussed as potential benchmarks for the long-term influence of biochar amendment and the post-wildfire influences on soil properties. In this study, we utilised a large soil sample dataset (n = 1245) from 52 RCH sites in north-western Connecticut, USA, to quantify SOC contents by total element analysis. The contents of condensed highly aromatic carbon as a proxy for black carbon (BC) were predicted by using a modified benzene polycarboxylated acid (BPCA) marker method in combination with diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy-based partial least square regression (r2 = 0.89). A high vertical spatial sampling resolution allowed the identification of soil organic matter (SOM) enrichment and translocation processes. The results show an average 75% and 1862% increase in TOC and BPCA-derived carbon, respectively, for technogenic Auh horizons compared to reference soils. In addition to an increase in aromatic properties, increased carboxylic properties of the RCH SOC suggest self-humification effects of degrading charcoal and thereby the continuing formation of leachable aromatic carbon compounds, which could have effects on pedogenic processes in buried soils. Indeed, we show BPCA-derived carbon concentrations in intermediate technogenic Cu horizons and buried top/subsoils that suggest vertical translocation of highly aromatic carbon originating in RCH Auh horizons. Topmost Auh horizons showed a gradual decrease in total organic carbon (TOC) contents with increasing depth, suggesting accumulation of recent, non-pyrogenic SOM. Lower aliphatic absorptions in RCH soil spectra suggest different SOM turnover dynamics compared to reference soils. Furthermore, studied RCH soils featured additional TOC enrichment, which cannot be fully explained now. Y1 - 2022 UR - https://bsssjournals.onlinelibrary.wiley.com/doi/10.1111/ejss.13293 U6 - https://doi.org/10.1111/ejss.13293 VL - 73 IS - 4 SP - 1 EP - 16 ER - TY - GEN A1 - Preußer, Daniel A1 - Fischer, Thomas A1 - Juretzek, Thomas T1 - Effects of antibiotics ceftriaxone and levofloxacin on the growth of Protophormia terraenovae (Diptera: Calliphoridae) T2 - Forensic Science, Medicine and Pathology N2 - AbstractProtophormia terraenovae is a colonizer of decomposing bodies and is known to cause pre-mortem myiasis as the female flies lay eggs in uncleaned wounds. In this study the effects of different concentrations of antibiotics levofloxacin and ceftriaxone on maggot development, weight, length, and mortality were examined. The maggot length and weight were significantly increased by therapeutical doses of levofloxacin and ceftriaxone. The maggot development time was significantly decreased in every levofloxacin treatment compared to the control. The time to start pupation was significantly increased in the control compared to the antibiotic treatments. Levofloxacin significantly increased the survivability of the maggots. Every levofloxacin treatment significantly improved the rearing conditions for the maggots. Reaching the third instar was delayed by 24 h in the control compared to the Levo 3.57 treatment. The Pupation in the control was delayed by an average of 48 h compared to the Levo 3.57 treatment. The significantly reduced development time of the maggots in the antibiotic treatments might lead to an overestimation of the post-mortem interval and therefore an incorrect time of death determination. The improved rearing conditions may be an indication of the potential of a combined application of antibiotics and maggot therapy. KW - General Medicine KW - Pathology and Forensic Medicine Y1 - 2024 U6 - https://doi.org/10.1007/s12024-024-00804-9 SN - 1556-2891 SP - 1 EP - 13 ER - TY - GEN A1 - Preußer, Daniel A1 - Fischer, Thomas A1 - Juretzek, Thomas T1 - Effects of antibiotics ceftriaxone and levofloxacin on the growth of Lucilia sericata (Diptera: Calliphoridae) T2 - Medical and Veterinary Entomology N2 - Lucilia sericata is one of the most studied species in forensic entomology due to its widespread distribution, forensic importance as well as medical use. The growth and development stage of maggots is often used to determine the post-mortem interval in forensic cases. L. sericata can cause myiasis in humans who are not able to maintain personal hygiene due to age or medical condition and can therefore be used to determine the time period of neglect. The influence of the temperature on the maggot development has been examined in various studies. Different examinations on the effects of toxic substances on the maggot development and survival have been conducted in order to test the influence and resulting deviations. In this study, the effects of different therapeutical doses of the antibiotics ceftriaxone and levofloxacin were examined on L. sericata in order to determine and compare deviations in maggot development and survival. The used antibiotics did not significantly influence the maggot weight and length. A significant delay in the time of pupation has been determined in the treatments with high concentrations of levofloxacin. The mortality was significantly increased in all treatments with antibiotics compared to the control, whereby the survivability of all treatments remained over 80%. Because of the high doses needed to produce an effect, we concluded that an overestimation of the post-mortem interval is unlikely but higher antibiotic concentrations or possible interactions with other medications could increase the maggot development time. KW - antibiotics KW - blow flies KW - entomotoxicology KW - myiasis KW - post‐mortem interval Y1 - 2023 U6 - https://doi.org/10.1111/mve.12685 SN - 0269-283X SN - 1365-2915 VL - 37 IS - 4 SP - 805 EP - 815 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 - Spröte, Roland A1 - Fischer, Thomas A1 - Veste, Maik A1 - Lange, Philipp A1 - Bens, Oliver A1 - Raab, Thomas A1 - Hüttl, Reinhard F. T1 - Hydrophobicity in sandy soils triggered by the development of Scots Pine stands in southern Brandenburg, Germany T2 - EGU General Assembly 2010, held in Vienna, Austria, 02 – 07 May 2010 Y1 - 2010 UR - http://meetingorganizer.copernicus.org/EGU2010/EGU2010-4154.pdf N1 - EGU2010-4154 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Spröte, Roland A1 - Fischer, Thomas A1 - Veste, Maik A1 - Yair, Aaron A1 - Wiehe, Wolfgang A1 - Lange, Philipp A1 - Bens, Oliver A1 - Raab, Thomas A1 - Hüttl, Reinhard F. T1 - Structures and processes of biological soil crusts during initial ecosystem genesis of an artificial watershed in Lusatia, NE Germany T2 - EGU General Assembly 2010, held Vienna, Austria, 02 – 07 May 2010 Y1 - 2010 N1 - EGU2010-4129 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Spröte, Roland A1 - Veste, Maik A1 - Fischer, Thomas A1 - Raab, Thomas A1 - Bens, Oliver A1 - Hüttl, Reinhard F. T1 - Development of biological soil crusts and their influence on soil hydrology in the recultivation area of lignite open-cast mining district in Lower Lusatia (Germany) T2 - EGU General Assembly 2012, held 22-27 April, 2012 in Vienna Y1 - 2012 N1 - EGU2012-6372 PB - European Geophysical Society CY - Katlenburg-Lindau 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 - Fischer, Thomas A1 - Spröte, Roland A1 - Veste, Maik A1 - Wiehe, Wolfgang A1 - Lange, Philipp A1 - Bens, Oliver A1 - Raab, Thomas A1 - Hüttl, Reinhard F. T1 - Functions of biological soil crusts on central European inland dunes:Water repellency and pore clogging influence water infiltration T2 - EGU General Assembly 2010, held in Vienna, Austria, 02 – 07 May 2010 Y1 - 2010 UR - http://meetingorganizer.copernicus.org/EGU2010/EGU2010-4449.pdf N1 - EGU2010-4449 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Spröte, Roland A1 - Bens, Oliver A1 - Fischer, Thomas A1 - Raab, Thomas A1 - Hüttl, Reinhard F. T1 - Soil water repellency as a phenomenon of initial soil formation – approaches and first results from the Transregional Collaborative Reserch Centre (SFB/TRR) 38 T2 - EGU General Assembly 2009, held in Vienna, Austria, 19 – 24 April 2009 Y1 - 2009 UR - http://adsabs.harvard.edu/abs/2009EGUGA..11.9008S N1 - EGU2009-9008 PB - European Geophysical Society CY - Katlenburg-Lindau 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 - CHAP A1 - Spröte, Roland A1 - Veste, Maik A1 - Fischer, Thomas A1 - Lange, Philipp A1 - Bens, Oliver A1 - Raab, Thomas A1 - Hüttl, Reinhard F. T1 - Wie beeinflussen Kiefern (Pinus sylvestris L.) die Entwicklung der Benetzungshemmung auf Sandböden? T2 - Böden verstehen - Böden nutzen - Böden fit machen, Jahrestagung der Deutschen Bodenkundlichen Gesellschaft, 3. - 9. September 2011 Y1 - 2011 UR - http://eprints.dbges.de/768/ ER - TY - CHAP A1 - Spröte, Roland A1 - Veste, Maik A1 - Fischer, Thomas A1 - Lange, Philipp A1 - Bens, Oliver A1 - Raab, Thomas A1 - Hüttl, Reinhard F. T1 - Development of biologicalsoil crusts in initial ecosystems in Lusatia, Germany T2 - DBG Jahrestagung 2009 Bonn "Böden - eine endliche Ressource", 05.-13.09.2009, Bonn Y1 - 2009 UR - http://eprints.dbges.de/178/ 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 - Elmer, Michael A1 - Bachmann, Ute A1 - Gutsch, Martin A1 - Schröder, Jens A1 - Bäucker, Ernst A1 - Lange, Mike A1 - Clauder, Lothar A1 - Bens, Oliver A1 - Suckow, Felicitas A1 - Kätzel, Ralf A1 - Bues, Claus-Thomas A1 - Frommhold, Heinz A1 - Sonntag, Herbert A1 - Fischer, Thomas A1 - Hüttl, Reinhard F. T1 - OakChain: Eichen-Kiefern-Mischbestände im Spannungsfeld von Klimawandel, Waldumbau und internationalem Holzmarkt T2 - Forst und Holz Y1 - 2009 SN - 0932-9315 VL - 64 IS - 7/8 SP - 26 EP - 29 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 - Sut-Lohmann, Magdalena A1 - Fischer, Thomas A1 - Repmann, Frank A1 - Raab, Thomas A1 - Dimitrova, Tsvetelina T1 - Feasibility of field portable near infrared (NIR) spectroscopy to determine cyanide concentrations in soil T2 - Water, Air and Soil Pollution N2 - Vicinities of manufactured gas plants were often contaminated with solid iron–cyanide complexes as a result of the coal gasification process. During the remediation of affected soils, knowledge about contaminant concentrations is crucial, but laboratory methods are often expensive and time consuming. Rapid and non-destructive field methods for contaminant determination permit an analysis of large sample numbers and hence, facilitate identification of ‘hot spots’ of contamination. Diffuse near infrared reflectance spectroscopy has proven to be a reliable analytical tool in soil investigation. In order to determine the feasibility of a Polychromix Handheld Field Portable Near-Infrared Analyzer (FP NIR), various sample preparation methods were examined, including homogenizing, sieving, drying, and grinding. Partial least squares calibration models were developed to determine near infrared (NIR) spectral responses to the cyanide concentration in the soil samples. As a control, the contaminant concentration was determined using conventional flow injection analysis. The experiments revealed that portable near-infrared spectrometers could be a reliable device for detecting cyanide concentrations >2,400 mgkg−1 in the field and >1,750 mgkg−1 after sample preparation in the laboratory.We found that portable NIR spectrometry cannot replace traditional laboratory analyses due to high limits of detection, but that it could be used for identification of contamination ‘hot spots’. Y1 - 2012 U6 - https://doi.org/10.1007/s11270-012-1298-y SN - 1573-2932 VL - 223 IS - 8 SP - 5495 EP - 5504 ER - TY - GEN A1 - Sut-Lohmann, Magdalena A1 - Fischer, Thomas A1 - Repmann, Frank A1 - Raab, Thomas T1 - Long-Term Release of Iron-Cyanide Complexes from the Soil of a Manufactured Gas Plant Site T2 - Journal of Environmental Protection N2 - Iron-cyanide (Fe-CN) complexes have been detected at Manufactured Gas Plant sites (MGP) worldwide. The risk of groundwater contamination depends mainly on the dissolution of ferric ferrocyanide. In order to design effective reme- diation strategies, it is relevant to understand the contaminant’s fate and transport in soil, and to quantify and mathe- matically model a release rate. The release of iron-cyanide complexes from four contaminated soils, originating from the former MGP in Cottbus, has been studied by using a column experiment. Results indicated that long-term cyanide (CN) release is governed by two phases: one readily dissolved and one strongly fixed. Different isotherm and kinetic equations were used to investigate the driving mechanisms for the ferric ferrocyanide release. Applying the isotherm equations assumed an approach by which two phases were separate in time, whereas the multiple first order equation considered simultaneous occurrence of both cyanide pools. Results indicated varying CN release rates according to the phase and soil. According to isotherm and kinetic models, the long-term iron cyanide release from the MGP soils is a complex phenomenon driven by various mechanisms parallely involving desorption, diffusion and transport processes. Phase I (rapid release) is presumably mainly constrained by the transport process of readily dissolved iron-cyanide complexes combined with desorption of CN bound to reactive heterogeneous surfaces that are in direct contact with the aqueous phase (outer-sphere complexation). Phase II (limited rate) is presumably driven by the diffusion controlled processes involving dissolution of precipitated ferric ferrocyanide from the mineral or inner-sphere complexation of fer- ricyanides. CN release rates in phase I and II were mainly influenced by the pH, organic matter (OM) and the total CN content. The cyanide release rates increased with increasing pH, decreased with low initial CN concentration and were retarded by the increase in OM content. Y1 - 2013 U6 - https://doi.org/10.4236/jep.2013.411A2002 SN - 2152-2219 VL - 4 IS - 11B SP - 8 EP - 19 ER - TY - CHAP A1 - Sut-Lohmann, Magdalena A1 - Fischer, Thomas A1 - Repmann, Frank A1 - Raab, Thomas T1 - Feasibility of field portable near infrared (NIR) spectroscopy to determine cyanide concentrations in soil T2 - European Geosciences Union, General Assembly 2013, Vienna, Austria, 07 – 12 April 2013 N2 - In Germany, at more than 1000 sites, soil is polluted with an anthropogenic contaminant in form of iron-cyanide complexes. These contaminations are caused by former Manufactured Gas Plants (MGPs), where electricity for lighting was produced in the process of coal gasification. The production of manufactured gas was restrained in 1950, which caused cessation of MGPs. Our study describes the application of Polychromix Handheld Field Portable Near-Infrared (NIR) Analyzer to predict the cyanide concentrations in soil. In recent times, when the soil remediation is of major importance, there is a need to develop rapid and non-destructive methods for contaminant determination in the field. In situ analysis enables determination of ‘hot spots’, is cheap and time saving in comparison to laboratory methods. This paper presents a novel usage of NIR spectroscopy, where a calibration model was developed, using multivariate calibration algorithms, in order to determine NIR spectral response to the cyanide concentration in soil samples. As a control, the contaminant concentration was determined using conventional Flow Injection Analysis (FIA). The experiments revealed that portable near-infrared spectrometers could be a reliable device for identification of contamination ‘hot spots’, where cyanide concentration are higher than 2400 mg kg-1 in the field and >1750 mg kg-1 after sample preparation in the laboratory, but cannot replace traditional laboratory analyses due to high limits of detection. Y1 - 2013 UR - http://meetingorganizer.copernicus.org/EGU2013/EGU2013-1986.pdf N1 - EGU2013-1986 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - GEN A1 - Rodionov, Andrei A1 - Nii-Annang, Seth A1 - Fischer, Thomas A1 - Gattinger, Andreas A1 - Bens, Oliver A1 - Raab, Thomas A1 - Hüttl, Reinhard F. T1 - Cross-linked polyacrylates in post-mining substrates: persistence and effects on plant growth T2 - Soil Use and Management N2 - Application of hydrophilic polymers composed of cross-linked polyacrylate can improve soil water-holding capacity and accelerate the restoration of post-mining substrates. In this work, we studied the persistence of a polyacrylate polymer incorporated into a soil and its impact on plant nutrients at a reclamation site of former lignite mining in Lusatia (Germany). In contrast to autumn application, the incorporation of the polymer enhanced the sequestration of plant-derived carbon in the soil, which was reflected by a significant increase in the concentration of a lignin marker. Attenuated total reflexion–Fourier transform infrared spectra (ATR-FTIR) and total elemental contents in the applied polymer suggested an intensive cation exchange between the polymer framework and the soil-forming substrate. In addition, there was an enrichment of carbonaceous material, which seems to reduce the swelling and thus the water-holding capacity of the cross-linked polyacrylate. Conversely, this process protected the polymer structure from rapid decomposition. Y1 - 2014 U6 - https://doi.org/10.1111/sum.12103 SN - 1475-2743 VL - 30 IS - 1 SP - 78 EP - 87 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 - 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 - 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 - TY - CHAP A1 - Bachmann, Ute A1 - Bens, Oliver A1 - Elmer, Michael A1 - Fischer, Thomas A1 - Raab, Thomas A1 - Hüttl, Reinhard F. ED - Elmer, Michael ED - Kätzel, Ralf ED - Bens, Oliver ED - Bues, Claus-Thomas ED - Sonntag, Herbert ED - Hüttl, Reinhard F. T1 - Boden und Standortqualität T2 - Nachhaltige Bewirtschaftung von Eichen-Kiefern-Mischbeständen : im Spannungsfeld von Klimawandel, Waldumbau und internationalem Holzmarkt Y1 - 2009 SN - 978-3-86581-196-7 SP - 31 EP - 44 PB - oekom CY - München ER - TY - CHAP A1 - Fischer, Thomas A1 - Schneider, Bernd Uwe A1 - Baumann, Karen A1 - Hüttl, Reinhard F. T1 - Spatial Distribution of Black pine (Pinus nigra L.) roots and its relationship to chemical properties of bulk and rhizosphere soil equilibrium solution T2 - Woody Root Processes: Revealing the Hidden Half : Sade Boqer, Israel, 4-6 February 2006 Y1 - 2006 UR - http://books.google.de/books/about/Woody_Root_Processes.html?id=KHkntwAACAAJ&redir_esc=y ER - TY - CHAP A1 - Gypser, Stella A1 - Fischer, Thomas A1 - Lange, Philipp A1 - Veste, Maik T1 - Impact of biocrust succession on water retention and repellency on open-cast lignite mining sites under reclamation in Lower Lusatia, NE-Germany T2 - European Geosciences Union, General Assembly 2016, Vienna, Austria N2 - Mining activities can strongly affect ecosystem properties by destruction of naturally developed soils and removal of vegetation. The unstructured substrates show high bulk densities, compaction, low water infiltration rates, reduced water holding capacities and higher susceptibility to wind and water erosion. In the initial stage of the ecosystem development, the post-mining sites are open areas without or with a low cover of higher vegetation. It is well-known that biocrusts are able to colonize the soil surface under such extreme conditions without human support and affect soil hydrological processes such as water infiltration, run-off or re-distribution. Investigations were conducted on two former lignite open-cast mining sites, an artificial sand dune on the reclaimed watershedWelzow “Neuer Lugteich” and a reforestation area in Schlabendorf (Brandenburg, north-east Germany). The aim was to relate the hydrological characteristics of the topsoil to successional stages of biological soil crusts on reclaimed soils and their influence on repellency index and water holding capacity compared to pure mining substrate. Our study emphasized the influence of changing successional stages and species composition of biological soil crusts, forming a small-scale crust pattern, on water repellency and retention on sandy soils in temperate climate. Different successional stages of soil crusts were identified from initial scattered green algae crusts, dominated by Zygogonium spec. and Ulothrix spec., and more developed soil crusts containing mosses such as Ceratodon purpureus and Polytrichum piliferum. Lichens of the Genus Cladonia were more pronouncedly contributed to biocrusts at later and mature stages of development. The repellency index on the one hand increased due to the cross-linking of sand particles by the filamentous green algae Zygogonium spec. which resulted in clogging of pores, and on the other hand decreased with the occurrence of moss plants 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 absorption capacity of soil crust biota as well as a decreased pore diameter in the green algae layers positively affected the water retention of crusted soil compared to pure substrate. The occurrence of bryophytes with later succession weakened the repellent behavior of the biocrusts, increased infiltration, and might have affected the run-off at small-scale on biocrusts. Certainly, the biological soil crusts showed water repellent properties but no distinctive hydrophobic characteristics. On both locations, similar trends of water repellency and retention related to crustal formation were observed, in spite of different relief, reclamation time and inhomogeneous distribution of crustal organisms. Y1 - 2016 UR - http://meetingorganizer.copernicus.org/EGU2016/EGU2016-7015.pdf N1 - EGU2016-7015 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Fischer, Thomas A1 - Veste, Maik A1 - Eisele, Andreas A1 - Bens, Oliver A1 - Spyra, Wolfgang A1 - Hüttl, Reinhard F. T1 - High resolution mapping of Normalized Difference Vegetation Indices (NDVI) of biological soil crusts T2 - EGU General Assembly 2012, held 22-27 April, 2012 in Vienna Y1 - 2012 N1 - EGU2012-7052 PB - European Geophysical Society CY - Katlenburg-Lindau ER -