@misc{XiaoWangFanetal., author = {Xiao, Bo and Wang, Huifang and Fan, Jun and Fischer, Thomas and Veste, Maik}, title = {Biological soil crusts decrease soil temperature in summer and increase soil temperature in winter in semiarid environment}, series = {Ecological Engineering}, volume = {58}, journal = {Ecological Engineering}, issn = {0925-8574}, doi = {10.1016/j.ecoleng.2013.06.009}, pages = {52 -- 56}, abstract = {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.}, language = {en} } @misc{FischerYairVesteetal., author = {Fischer, Thomas and Yair, Aaron and Veste, Maik and Geppert, Helmut}, title = {Hydraulic properties of biological soil crusts on sand dunes studied by 13C-CP/MAS-NMR: a comparison between an arid and a temperate site}, series = {Catena}, volume = {110}, journal = {Catena}, issn = {0341-8162}, doi = {10.1016/j.catena.2013.06.002}, pages = {155 -- 160}, abstract = {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.}, language = {en} } @inproceedings{FischerVesteMykhailova, author = {Fischer, Thomas and Veste, Maik and Mykhailova, Larysa}, title = {Ecological Maturity and Drought Stress of Biological Soil Crusts along a Central European Inland Dune Catena}, series = {European Geosciences Union, General Assembly 2014, Vienna, Austria, 27 April - 02 May 2014}, booktitle = {European Geosciences Union, General Assembly 2014, Vienna, Austria, 27 April - 02 May 2014}, publisher = {European Geophysical Society}, address = {Katlenburg-Lindau}, language = {en} } @inproceedings{FischerYairGeppertetal., author = {Fischer, Thomas and Yair, Aaron and Geppert, Helmut and Veste, Maik}, title = {Water repellency and infiltration of biological soil crusts on an arid and a temperate dunes}, series = {European Geosciences Union, General Assembly 2014, Vienna, Austria, 27 April - 02 May 2014}, booktitle = {European Geosciences Union, General Assembly 2014, Vienna, Austria, 27 April - 02 May 2014}, publisher = {European Geophysical Society}, address = {Katlenburg-Lindau}, language = {en} } @inproceedings{LippertNixdorfLessmannetal., author = {Lippert, Gudrun and Nixdorf, Brigitte and Leßmann, Dieter and Henschke, Ingo and Veste, Maik and B{\"o}hme, Michael}, title = {Prim{\"a}rsukzession einem Kleingew{\"a}sser (H{\"u}hnerwasserteich) - Teil 2: Vergleich der Produktion von Phytoplankton, Makrophyten und heterotrophen Bakterien}, series = {Erweiterte Zusammenfassung der Jahrestagung der DGL 2009 in Oldenburg}, booktitle = {Erweiterte Zusammenfassung der Jahrestagung der DGL 2009 in Oldenburg}, publisher = {Eigenverlag der DGL}, address = {Hardegsen}, isbn = {978-3-9802188-8-7}, pages = {84 -- 89}, language = {de} } @inproceedings{FischerGypserSubbotinaetal., author = {Fischer, Thomas and Gypser, Stella and Subbotina, Maria and Veste, Maik}, title = {Hydraulic and nutritional feedback controls surface patchiness of biological soil crusts at a post-mining site}, series = {European Geosciences Union, General Assembly 2015, Vienna, Austria, 13 April - 17 May 2015}, booktitle = {European Geosciences Union, General Assembly 2015, Vienna, Austria, 13 April - 17 May 2015}, publisher = {European Geophysical Society}, address = {Katlenburg-Lindau}, language = {en} } @inproceedings{KleefeldVeste, author = {Kleefeld, Andreas and Veste, Maik}, title = {Robuste und strukturerhaltende Bildentrauschung via Medianfilterung und Bildsegmentierung}, series = {20. und 21. Workshop Computer-Bildanalyse in der Landwirtschaft, 26. Mai 2014, Osnabr{\"u}ck}, booktitle = {20. und 21. Workshop Computer-Bildanalyse in der Landwirtschaft, 26. Mai 2014, Osnabr{\"u}ck}, publisher = {Leibniz-Institut f{\"u}r Agrartechnik Potsdam-Bornim e.V.}, address = {Potsdam}, issn = {0947-7314}, pages = {92 -- 100}, abstract = {Ein Medianfilter ist ein Werkzeug, das benutzt werden kann, um Bilder zu entrauschen. Allerdings verschwimmen vorhandene Strukturen, und eine gute Bildsegmentierung gestaltet sich schwierig. Daher wird hier ein Medianfilteralgorithmus vorgestellt, der in der Lage ist, Bilder zu entrauschen und gleichzeitig vorhandene Strukturen beizubehalten. Wir zeigen die Anwendbarkeit dieser Methode auf Bilder, die durch ein automatisches Minirhizotronsystem aufgenommen worden sind. Dieses dient zur zerst{\"o}rungsfreien Observierung von Wurzelwachstum. Die verbesserten Bilder werden dann zur Bildsegmentierung benutzt, um automatisch die Wurzeln in den Bildern zu entdecken.}, language = {de} } @inproceedings{ZaplataVestePohleetal., author = {Zaplata, Markus K. and Veste, Maik and Pohle, Ina and Sch{\"u}mberg, Sabine and Abreu Schonert, Iballa and Hinz, Christoph}, title = {Experimental investigation of the early interaction between cyanobacterial soil crusts and vascular plants}, 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 = {While there are hints that biological soil crusts (BSCs) can constitute physical barriers for the emergence of vascular plants, a conceptual approach for the quantitative evaluation of these effects is still missing. Here we present an experimental design to test the emergence of seedlings in situ with (i) capping natural intact, (ii) destroyed and (iii) removed BSC. The selected field site is directly adjacent to the constructed H{\"u}hnerwasser catchment (Lusatia, Germany). This site exists since the end of 2008 and consists of loamy sand. Serving as proxy for seedling thrust, we inserted pre-germinated seeds of three confamiliar plant species with different seed masses (members of the Fabaceae family: Lotus corniculatus L., Ornithopus sativus Brot., and Glycine max (L.) Merr.). In each treatment as well as in the control group planting depths were 10 mm. We took care that experimental plots had identical crust thickness, slightly less than 4 mm, serving as proxy for mechanical resistance. A plot became established as follows: Firstly, the pristine crusted surface was vertically cut. To the windward side the BSC remained intact (i: "with BSC" stripe). To the downwind side soil material was temporarily excavated for laterally inserting the seeds beneath the surface of the first stripe. Then at the thereby disturbed second stripe pulverised BSC material became filled as a top layer (ii: "BSC mix" stripe). From the next stripe the BSC was removed (iii : "no BSC" stripe). Thus each plot had each experimental group in spatial contiguity (within 50 cm * 50 cm). The overall 50 plots were distributed across an area of 40 m * 12 m. When individuals of a species either emerged at all stripes, "XXX", or at no stripe of a plot, "- - -", there was no reason to suppose any effect of a crust. The "-XX" emergence pattern (depicting the appearance of seedlings in both stripes possessing manipulated surfaces) points towards hindrance more clearly than "-X-" or "- - X". Altogether eight possible combinations exist. Combinatorial analysis turned out that seedling emergence had been notably impeded for light-weighted seeds but little for heavy seeds. Repeated recordings enable to account for adaptable emergence of seedlings according to varying crust conditions - in spatial as well as temporal terms. The proposed experimental procedure hence is highly recommended as a viable instrument to further investigate filter and facilitation processes between BSCs and vascular plants.}, language = {en} } @misc{ZaplataSchuembergKidronetal., author = {Zaplata, Markus K. and Sch{\"u}mberg, Sabine and Kidron, Giora J. and Ramm, Jessica and Veste, Maik}, title = {Impacts of cyanobacteria-dominated biological soil crusts on seedling emergence and fate: an in situ experiment}, series = {Pant and Soil : an International Journal on Plant-Soil Relationships}, journal = {Pant and Soil : an International Journal on Plant-Soil Relationships}, doi = {10.1007/s11104-024-06869-3}, pages = {16}, abstract = {Background and aims Biological soil crusts (BSCs) co-occur with vascular plants in many ecosystems. Nevertheless, little is known regarding the interaction among BSCs and vascular plants, and no standard methods exist aiming to evaluate BSC-plant interactions. While some reports emphasized the inhibition effect of BSCs on germination, others reported the opposite or did not find any differences between germination under crusted and non-crusted conditions. Contradictory findings were also reported regarding the BSC effects on vascular plants after germination, with some reports claiming that BSCs promote growth, while others claim the opposite. Methods By a seed addition experiment (using light and heavy seeds of three species belonging to the Fabaceae family) in an early-successional system in Germany, we tested in situ the emergence of seedlings under variable surface conditions (cyanobacterial crust, disturbed and removed crust), and quantified crust-plant interactions (survival, flowering) during and following seedling emergence. Results In comparison to an average of 8\% of the light Lotus corniculatus and 20\% of the light Ornithopus sativus that emerged through the cyanobacterial BSC, 76\% of the heavy Glycine max emerged. Once emerged, the crust did not significantly affect the survival, growth, biomass, or flowering of G. max, whereas many of the seedlings from lightweight seeds dried up soon after emergence. The thickness of the cyanobacterial biocrust had no influence on Fabaceae emergence. Conclusion The cyanobacterial BSC acted as a filter that hindered the emergence of the lightweight seeds.}, language = {en} } @misc{GerwinSchaafBiemeltetal., author = {Gerwin, Werner and Schaaf, Wolfgang and Biemelt, Detlef and Winter, S. and Fischer, Annette and Veste, Maik and H{\"u}ttl, Reinhard F.}, title = {Overview and first results of ecological monitoring at the artificial watershed Chicken Creek (Germany)}, series = {Physics and Chemistry of the Earth}, volume = {36}, journal = {Physics and Chemistry of the Earth}, number = {1-4}, issn = {1873-5193}, pages = {61 -- 73}, language = {en} }