@misc{HuettlFischer, author = {H{\"u}ttl, Reinhard F. and Fischer, Thomas}, title = {Carbon sequestration and landscape ecology in Western Europe - editorial}, series = {Ecological Engineering}, volume = {29}, journal = {Ecological Engineering}, number = {4}, issn = {0925-8574}, doi = {10.1016/j.ecoleng.2006.10.001}, pages = {317 -- 318}, language = {en} } @misc{FischerVesteEiseleetal., author = {Fischer, Thomas and Veste, Maik and Eisele, Andreas and Bens, Oliver and Spyra, Wolfgang and H{\"u}ttl, Reinhard F.}, title = {Small Scale Spatial Heterogeneity of Normalized Difference Vegetation Indices (NDVI) and Hot Spots of Photosynthesis in Biological Soil Crusts}, series = {Flora}, volume = {207}, journal = {Flora}, number = {3}, doi = {10.1016/j.flora.2012.01.001}, pages = {159 -- 167}, abstract = {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.}, language = {en} } @misc{FischerVesteSchaafetal., author = {Fischer, Thomas and Veste, Maik and Schaaf, Wolfgang and D{\"u}mig, Alexander and K{\"o}gel-Knabner, Ingrid and Wiehe, Wolfgang and Bens, Oliver and H{\"u}ttl, Reinhard F.}, title = {Initial pedogenesis in a topsoil crust 3 years after construction of an artificial water catchment in Brandenburg, NE Germany}, series = {Biogeochemistry}, volume = {101}, journal = {Biogeochemistry}, number = {1-3}, issn = {1573-515X}, doi = {10.1007/s10533-010-9464-z}, pages = {165 -- 176}, abstract = {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.}, language = {en} } @misc{DillyNiiAnnangFrankeetal., author = {Dilly, Oliver and Nii-Annang, Seth and Franke, Gabriele and Fischer, Thomas and Buegger, Franz and Zyakun, Anatoly}, title = {Resilience of microbial respiration, respiratory quotient and stable isotope characteristics to soil hydrocarbon addition}, series = {Soil Biology and Biochemistry}, volume = {43}, journal = {Soil Biology and Biochemistry}, number = {9}, issn = {0038-0717}, doi = {10.1016/j.soilbio.2010.09.026}, pages = {1808 -- 1811}, abstract = {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.}, language = {de} } @incollection{BergmannFischerHuettl, author = {Bergmann, Charlotte and Fischer, Thomas and H{\"u}ttl, Reinhard F.}, title = {Decomposition of needle-, herb- and root- litter and Of-layer humus in three scots pine stands}, series = {Changes of atmospheric chemistry and effects on forest ecosystems: A roof experiment without roof.}, booktitle = {Changes of atmospheric chemistry and effects on forest ecosystems: A roof experiment without roof.}, editor = {H{\"u}ttl, Reinhard F. and Bellmann, Klaus}, publisher = {Kluwer Academic Publishers}, address = {Dordrecht}, isbn = {0-7923-5713-2}, pages = {151 -- 176}, language = {en} } @incollection{BergmannFischerHuettl, author = {Bergmann, Charlotte and Fischer, Thomas and H{\"u}ttl, Reinhard F.}, title = {Seasonal variability of organic matter and N input with litterfall in three scots pine stands}, series = {Changes of atmospheric chemistry and effects on forest ecosystems: A roof experiment without roof}, booktitle = {Changes of atmospheric chemistry and effects on forest ecosystems: A roof experiment without roof}, editor = {H{\"u}ttl, Reinhard F. and Bellmann, Klaus}, publisher = {Kluwer Academic Publishers}, address = {Dordrecht}, isbn = {0-7923-5713-2}, pages = {177 -- 186}, language = {en} } @incollection{HuettlFischer, author = {H{\"u}ttl, Reinhard F. and Fischer, Thomas}, title = {Wirkungen auf Boden und Bodenorganismen}, language = {de} } @inproceedings{FischerSchneiderBaumannetal., author = {Fischer, Thomas and Schneider, Bernd Uwe and Baumann, Karen and H{\"u}ttl, Reinhard F.}, title = {Spatial Distribution of Black pine (Pinus nigra L.) roots and its relationship to chemical properties of bulk and rhizosphere soil equilibrium solution}, series = {Woody Root Processes: Revealing the Hidden Half : Sade Boqer, Israel, 4-6 February 2006}, booktitle = {Woody Root Processes: Revealing the Hidden Half : Sade Boqer, Israel, 4-6 February 2006}, language = {en} } @inproceedings{GypserFischerLangeetal., author = {Gypser, Stella and Fischer, Thomas and Lange, Philipp and Veste, Maik}, title = {Impact of biocrust succession on water retention and repellency on open-cast lignite mining sites under reclamation in Lower Lusatia, NE-Germany}, series = {European Geosciences Union, General Assembly 2016, Vienna, Austria}, booktitle = {European Geosciences Union, General Assembly 2016, Vienna, Austria}, publisher = {European Geophysical Society}, address = {Katlenburg-Lindau}, abstract = {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.}, language = {en} } @inproceedings{FischerVesteEiseleetal., author = {Fischer, Thomas and Veste, Maik and Eisele, Andreas and Bens, Oliver and Spyra, Wolfgang and H{\"u}ttl, Reinhard F.}, title = {High resolution mapping of Normalized Difference Vegetation Indices (NDVI) of biological soil crusts}, series = {EGU General Assembly 2012, held 22-27 April, 2012 in Vienna}, booktitle = {EGU General Assembly 2012, held 22-27 April, 2012 in Vienna}, publisher = {European Geophysical Society}, address = {Katlenburg-Lindau}, language = {en} } @inproceedings{FischerSteinerKrakau, author = {Fischer, Thomas and Steiner, A. and Krakau, U.}, title = {Influence of nitrogen deposition on root mineralization and turnover in two Scots pine (Pinus sylvestris L.) stands in northeastern Germany}, language = {en} } @inproceedings{KruemmelbeinFischerRaabetal., author = {Kr{\"u}mmelbein, Julia and Fischer, Scarlett and Raab, Thomas and H{\"u}ttl, Reinhard F.}, title = {Bodenphysikalische Kenngr{\"o}ßen und deren fl{\"a}chenhafte Heterogenit{\"a}t auf einer homogen hergestellten Fl{\"a}che der Bergbaufolgelandschaft in der Lausitz}, series = {B{\"o}den - eine endliche Ressource, Jahrestagung der Deutschen Bodenkundlichen Gesellschaft, 5. bis 13. September 2009, Bonn}, booktitle = {B{\"o}den - eine endliche Ressource, Jahrestagung der Deutschen Bodenkundlichen Gesellschaft, 5. bis 13. September 2009, Bonn}, publisher = {Deutsche Bodenkundliche Gesellschaft (Selbstverlag)}, address = {Bonn}, language = {de} } @misc{SchowarteRiedelSafdaretal., author = {Schowarte, Julia and Riedel, Ramona and Safdar, Muddasar and Helle, Sven and Fischer, Thomas and Arellano-Garc{\´i}a, Harvey}, title = {Photocatalytic degradation of PFOA with porous lanthanoid perovskites nano catalyst}, series = {Chemie - Ingenieur - Technik : CIT}, journal = {Chemie - Ingenieur - Technik : CIT}, publisher = {Wiley-VCH GmbH}, address = {Weinheim}, issn = {1522-2640}, doi = {10.1002/cite.70027}, pages = {1 -- 11}, abstract = {Perfluorooctanoic acid (PFOA), a persistent environmental pollutant, poses significant health and ecological risks. This study investigates for the first time the photocatalytic degradation of PFOA using novel doped perovskite catalysts under polychromatic UV-VIS irradiation with a peak emission at 366 nm. A series of nickel- and lanthanide-doped perovskites (NiMn2O4, LaMnO3, NdMnO3, and their nickel-doped variants) were synthesized via a facile co-precipitation technique and characterized using X-ray diffraction (XRD), UV-VIS diffuse reflectance spectroscopy (UV-VIS-DRS), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), N2-physisorption, and microwave plasma atomic emission spectroscopy (MP-AES). Photocatalytic experiments revealed that Ni/NdMnO3 exhibited the highest degradation efficiency toward PFOA, likely due to its small band gap energy of 1.5 eV, facilitating efficient C-C bond cleavage.}, language = {en} } @misc{SchowarteRiedelSafdaretal., author = {Schowarte, Julia and Riedel, Ramona and Safdar, Muddasar and Helle, Sven and Fischer, Thomas and Arellano-Garcia, Harvey}, title = {Photocatalytic degradation of PFOA with porous lanthanoid perovskites nano catalyst}, series = {Chemie Ingenieur Technik}, volume = {98}, journal = {Chemie Ingenieur Technik}, number = {1-2}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1522-2640}, doi = {10.1002/cite.70027}, pages = {7 -- 17}, abstract = {Perfluorooctanoic acid (PFOA), a persistent environmental pollutant, poses significant health and ecological risks. Thisstudy investigates for the first time the photocatalytic degradation of PFOA using novel doped perovskite catalysts underpolychromatic UV-VIS irradiation with a peak emission at 366 nm. A series of nickel- and lanthanide-doped perovskites(NiMn2 O 4 , LaMnO 3 , NdMnO 3 , and their nickel-doped variants) were synthesized via a facile co-precipitation techniqueand characterized using X-ray diffraction (XRD), UV-VIS diffuse reflectance spectroscopy (UV-VIS-DRS), scanning elec-tron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), N2 -physisorption, and microwave plasma atomicemission spectroscopy (MP-AES). Photocatalytic experiments revealed that Ni/NdMnO3 exhibited the highest degradationefficiency toward PFOA, likely due to its small band gap energy of 1.5 eV, facilitating efficient C-C bond cleavage.}, language = {en} }