@misc{GypserVeste, author = {Gypser, Stella and Veste, Maik}, title = {Importance of P limitation for the C:N:P ratio in Robinia plantations on marginal sites}, series = {Gf{\"O} 2019, Science Meets Practice, 49th Annual Meeting of the Ecological Society of Germany, Austria and Switzerland, university of M{\"u}nster, 9-13 September 2019}, journal = {Gf{\"O} 2019, Science Meets Practice, 49th Annual Meeting of the Ecological Society of Germany, Austria and Switzerland, university of M{\"u}nster, 9-13 September 2019}, editor = {Thiede, Julia and Klein-Rauthake, Theresa}, pages = {82}, abstract = {Due to disturbances of soils after open-cast lignite mining activities in the Lusatian mining district, Northeast Germany, large areas covered with excavated and dumped material. These initial soils are characterized by a lack of nutrients and organic matter which is why Robinia pseudoacacia was established during reclamation of those marginal sites. As a pioneer species, Robinia is well suitable for the establishment on reclaimed forest ecosystems due to the N fixation capability and its ability to grow on a nutrient-poor sandy substrate with low water holding capacity. Since the N requirement of the Robinia can be covered by symbiotic nodule bacteria, P is important as a growth-limiting nutrient. Even though the total and available P in soils increased with the age of the plantings (planted between 1995 and 2007), the ratio of available to total P decreased relative to younger plantings. Despite the accumulation of organic matter and the decomposition of organic bound P, the bioavailability is affected by ad- and desorption processes, especially on Fe- and Al-hydroxides. It was hypothesized that the P demand of young trees, initially provided by a one-time fertilizer application, exceeds the P supply by mineralization over time. As a first step, kinetics of P desorption from synthetic Fe- and Al-hydroxides were characterized by using humic acid as a model organic compound, to detect fast and slow releasable P over time. At the Robinia sites, soil samples were examined at different depth with regard to their C, N and P concentrations. From the first results, we can conclude that the P availability and its limitation influences the growth performance of Robinia as well as the N-fixing symbiotic bacteria and, thus, the C:N:P ratio as a long-term effect on an ecosystem scale.}, language = {en} } @misc{VesteGypser, author = {Veste, Maik and Gypser, Stella}, title = {{\"O}kologische Funktionen und Dienstleistungen biologischer Bodenkrusten in Offenlandschaften - Fluch oder Segen?}, series = {Gf{\"O} 2019, Science Meets Practice, 49th Annual Meeting of the Ecological Society of Germany, Austria and Switzerland, university of M{\"u}nster, 9-13 September 2019}, journal = {Gf{\"O} 2019, Science Meets Practice, 49th Annual Meeting of the Ecological Society of Germany, Austria and Switzerland, university of M{\"u}nster, 9-13 September 2019}, address = {M{\"u}nster}, pages = {166}, abstract = {Initiale und n{\"a}hrstoffarme {\"O}kosysteme wie Grasl{\"a}nder und Offenlandschaften haben aus Sicht des Naturschutzes einen hohen Wert f{\"u}r die Landschaft und sind in der intensiv genutzten Kulturlandschaft Mitteleuropas selten geworden. Gerade Bergbaufolgelandschaften, aber auch gest{\"o}rte Binnend{\"u}nen, bieten Potenzial f{\"u}r die Entwicklung von initialen Lebensr{\"a}umen und Landschaften. Die obersten Millimeter der Bodenoberfl{\"a}che dieser {\"O}kosysteme werden durch Biokrusten besiedelt. Gebildet werden diese komplexen Lebensgemeinschaften aus einer Vielzahl von Cyanobakterien, Gr{\"u}nalgen, Moosen, Pilzen, Bakterien und Flechten. Diese Organismen „verkleben" die Bodenoberfl{\"a}che und beeinflussen als „{\"O}kosystem en miniature" maßgeblich die {\"o}kosystemaren Prozesse und die weitere Vegetationsentwicklung. Der Eintrag von C und N sowie die Akkumulation von organischem Material f{\"o}rdert die Bodenentwicklung in der initialen Phase. W{\"a}hrend der Sukzession der Biokrusten entwickeln sich die komplexen biotischen Prozesse des N-Kreislaufes mit R{\"u}ckkopplungen auf die N{\"a}hrstoffversorgung. Ausgeschiedene Exopolysaccharide, die eine Verbindung mit den Bodenpartikeln eingehen, verkleinern nach Regen den Porenraum der Bodenoberfl{\"a}che und vermindern die Infiltration. Besonders Moos- und Flechten-Krusten unterbinden bei geringen Niederschlagsintensit{\"a}ten die Infiltration in tiefere Bodenschichten. Konkurrenz und die großfl{\"a}chige Versiegelung der Bodenoberfl{\"a}che haben zudem negative Auswirkungen auf die Keimung und Etablierung von h{\"o}heren Pflanzen. Diese biotischen Interaktionen f{\"u}hren bei gesteuerten Sukzessionen auf Renaturierungsfl{\"a}chen zu {\"A}nderungen der Vegetationsentwicklung. Somit wird die Bedeutung der Biokrusten f{\"u}r die Renaturierungs{\"o}kologie z.T. kontrovers diskutiert. Klein- und großr{\"a}umige St{\"o}rungen hingegen sind als integraler Bestandteil der {\"O}kosystementwicklung einzuschließen.}, language = {de} } @inproceedings{HalkeGypserMantovanietal., author = {Halke, Christian and Gypser, Stella and Mantovani, Dario and Lebzien, Stefan and Freese, Dirk and Veste, Maik}, title = {Yield, transpiration and growth of the new bioenergy crop IGNISCUM Candy under different water regimes}, series = {Gf{\"O} 43rd Annual Meeting, Building bridges in ecology, linking systems, scales and disciplines, September 9 to 13, 2013, Potsdam, Germany}, booktitle = {Gf{\"O} 43rd Annual Meeting, Building bridges in ecology, linking systems, scales and disciplines, September 9 to 13, 2013, Potsdam, Germany}, editor = {Jeltsch, Florian and Joshi, Jasmin}, pages = {32 -- 33}, abstract = {There is a growing global need to produce more energy and reducing greenhouse gas emissions. One possible source of renewable energy in parts of Europe is the use of crop for bioenergy production. Currently, maize dominates the biogas production. For a diversified production of substrates alternative crops needs to be evaluated for their sustainable utilization and ecological integration into agro-systems. The new bioenergy plants IGNISCUM Candy and IGNISCUM Basic are cultivars of the Sakhalin Knotweed (Fallopia sachalinensis, Fam. Polygonaceae), which are characterized by a high annual biomass production. Information on the crop production of this species is rare. Hence, understanding plant response to the combinations of water and nutrients availability is crucial for the development of sustainable plant production. In greenhouse experiments we investigate the interrelations between nutrient supply, biomass production, and plant ecophysiology. For the determination of yield-transpiration relations at whole plant level we used a wick lysimeter system, which allows us to study plant growth under controlled water regimes and to calculate the plant transpiration. The irrigation is supplied by an automatic drip irrigation system and computer-controlled in relation to the volumetric soil water content. Four different water treatments associated to the SWC range from well-watered to drought stressed plants. The influence of plant sizes on plant water use was investigated under different nitrogen supply. The fertilizer applied is calcium ammonium nitrate (N) and the rates for the four treatments are 0, 50, 100, 150 kg N/ha at the beginning of the growing season. Plant transpiration is calculated on the basis of water input, storage and drainage in weekly intervals. The cumulative transpiration of the plants during the growing season is between 49 L (drought stressed) and 141 L (well-watered) per plant, respectively. We calculated a transpiration coefficient of 525 Liters per kg dry biomass.}, language = {en} } @misc{GypserFreese, author = {Gypser, Stella and Freese, Dirk}, title = {Mobilization of P from crystalline and amorphous Fe- and Al-hydroxides}, series = {EGU General Assembly 2020}, journal = {EGU General Assembly 2020}, doi = {10.5194/egusphere-egu2020-2871}, language = {en} }