@phdthesis{Grochowska2011, author = {Grochowska, Marta}, title = {{\"O}konomische, soziale und r{\"a}umliche Folgen der saisonalen Arbeitsmigration im Herkunftsgebiet : am Beispiel der Region Konin (Polen)}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, isbn = {978-3-86956-137-0}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-49649}, school = {Universit{\"a}t Potsdam}, pages = {390}, year = {2011}, abstract = {Die vorliegende Arbeit basiert auf Forschungen in den Jahren 2007-2009. Sie betrachtet die saisonale Arbeitsmigration aus der polnischen Region Konin, wo die Arbeitsmigration aus {\"o}konomischen Gr{\"u}nden, wie auch in {\"a}hnlich strukturierten Gebieten Polens, eine lange Tradition hat, die bis ins 19. Jahrhundert zur{\"u}ckgeht. Sie wird die saisonale Migration ins Ausland mit den {\"o}konomischen, sozialen und r{\"a}umlichen Auswirkungen aus der Perspektive des Einzelnen und seiner unmittelbaren Umgebung, aber auch der Gesellschaft und Herkunftsgebiet der Migranten betrachtet.}, language = {de} } @phdthesis{Althaus1999, author = {Althaus, Tilmann}, title = {Zur Geochemie der Edelgase ultramafischer Mantelxenolithe und Alkalibasalte der Persani-Berge, Transsilvanien, Rum{\"a}nien}, address = {Potsdam}, pages = {V, 129, A1 - C10 S. : graph. Darst.}, year = {1999}, language = {de} } @phdthesis{Nada2011, author = {Nada, Wael Mohamed Abdel-Rahman}, title = {Wood compost process engineering, properties and its impact on extreme soil characteristics}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-51046}, school = {Universit{\"a}t Potsdam}, year = {2011}, abstract = {The landfilling of biodegradable waste is proven to contribute to environmental degradation. Much wood and lumber is discharged as waste from the cleared fields. These woody wastes are subsequently disposed of by burning. However, it would be preferable to dispose of them without combustion to avoid the release of carbon dioxide, one of the critical greenhouse gases. Instead of burning these woody wastes, we should recycle them as future resources. One solution to this problem is to make compost from the waste. Compost use in agriculture is increasing as both an alternative to landfilling for the management of biodegradable waste, as well as means of increasing or preserving soil organic matter. This research aimed to contribute to the identification of a system for managing the production and utilization of wood waste (Quercus rubra and Pinus sylvestris) compost for sustainable agriculture, with particular regards to carbon dioxide produced from both compost and combustion of wood. Compost of wood was implemented in two consecutive trials. The first was carried out in greenhouse experiment in 4 liter pot of Quercus rubra and Pinus sylvestris (QR and PS) moisted by compost and tap water and infected by tiger worm (Eisenia fetida, EF) and European night crawlers (Dendrobaena veneta, DV) at different mixed ratios with lake mud (LM). The second was conducted in greenhouse experiment in 40 liter pot of the successful wood and worm from the first compost trial (QR and EF respectively). The tested wood (QR) was mixed separately by lake mud and horse manure and irrigated by compost and tap water. The final product, successful wood compost (QR) produced from the first trial (4 liter pot) was utilized in different mixed ratios with coal mine tailings (tertiary sand) in greenhouse pot trial to study his effects on improving soil physical and chemical properties and some plant growth parameters of RSM 7.2.1 grass. The wood compost produced from the second compost experiment (40 liter pot) and other artificial component named Arkadolith® were used as soil amelioration in field experiments of different selected sites with extremely unsuitable characteristics (tertiary and quaternary sand in Lusatia lignite region, Germany). The soil in each site was sowed by RSM 7.2.1 and autochthonous grasses. Also, some vermicompost samples were selected to study its thermal stability which compared with a soil sample (Niedermoorgleys) by using thermogravimetric analysis technique. Further investigation was achieved to evaluate the effect of charcoal as a source of carbon on vermicompost stability. Moreover some selected vermicompost samples were used to examine its microstructure under scanning electron microscope which compared also with the same soil used in thermal analysis. The obtained results under all studied experiments can be arranged as follow: First compost trial, Cumulative amount of carbon dioxide produced during composting period was lower than that evolved by combustion of wood. The results showed composting of wood can reduce the emitted CO2 up to 50 \% when compared with the amount of CO2 produced from combustion of wood. The effect of different studied factors on different studied parameters show that, QR wood compost have more responsive to decomposition processes and humification rate in comparison with PS wood compost. Under different infection worms, Eisenia fetida (EF) was better than Dendrobaena veneta (DV) in biodegradation rate. Compost water has had a better impact of tap water in all studied decomposition parameters. For example, The compost content of OM and total OC was decreased with the increase of the decomposition period in the treatments of compost water and EF worm, where this decrease was higher at mixed ratio of 1:3 (wood: mud, w/w). The total content of N in the final products takes reversible trend regarding to OM and C content. The high content of N was found in QR wood compost moisted by compost water and infected by EF worm. The content of both macro-and micro-nutrients was clearly positive affected by the studied factors. The content of these nutrients in QR wood compost was higher than that found in the compost of PS wood. Second compost trial, The observed data show that, the amount of CO2 produced by composting was lower than that evolved by combustion of wood. Composting of wood reduced CO2 emission up to 40 \% of the combustion wood CO2. Cumulative amount of CO2 produced from wood compost treated by horse manure was higher than that fount in the other treated by LM. The compost of wood treated by horse manure has had a high decomposition rate in comparison with that treated by lake mud. The treatments left without worms during all composting period and moisted by compost water have a responsive effects but it was lower than that infected by worms. Total and available contents of N, P, K, Mg, Zn, and Cu in the compost treated by HM were higher than that found in compost treated by LM. The other nutrients (Ca, Fe, Cu, and Mn) take reversible trend, which it was higher in LM than HM treatments. Thermal and microstructure analysis, The selected vermicompost samples from both first and second compost experiments showed, up to 200° C temperature the mass loss was due to free water and bound water (It was in vermicompost samples higher than soil sample). Mass loss from 200 to 550° C is due to easily oxidizable organic forms and it was higher in vermicompost than soil. In this stage the soil OM seems to be more stable than vermicompost which can be explained by a more intensive bond between the organic and inorganic components. At higher temperatures (T> 550° C) no significant detectable was appeared of soil organic matter. In contrast, the vermicompost treatments showed a high proportion of stable groups, especially aromatic compounds. These statements seem to be importance particularly for the practical application of the wood compost in terms of their long-term effect in the soil. The application of charcoal, showed no additional stabilizing effect of vermicompost. Also, the data show that, vermicompost structure characterized with high homogeneity and ratio of surface area to volume compared to those in soil structure. First plant trials (greenhouse), Different compost mixed ratios had positive impact on different extreme soil physiochemical properties. At the end of experiment (42 days) compost increased soil water holding capacity, decreased soil bulk and particle density and increased total porosity. The used wood compost modified soil buffering capacity and soil acidity. The availability of soil macro and micro nutrients were increased after adding wood compost. The wood compost had a positive effect in some growth parameters like fresh and dry matter yield of the selected grass. High dry matter yield and nutrients uptake was achieved with higher rates of compost application (25.0\% > 12.5\% > 3.0\% > 0.0 \%, w/w). Second plant trials (field experiment), Regarding to the effect of wood compost (QR) and Arkadolith® component on tertiary and quaternary sand, at the end of grown season (6 month) most soil and plant characteristics of tertiary sand were improved and it was better than that in quaternary sand. This trend reveals to, physical and chemical properties of tertiary sand was better than that in quaternary sand, like organic matter content, CEC, WHC, TOC, available nutrients. In the both sites, the effects of different type of soil conditioners arranged as follow: the treatments treated with wood compost is the better followed by the other treated with both wood compost and Arkadolith. Wood compost increased soil pH, CEC, soil buffering capacity, OM content, and soil WHC in comparison with Arkadolith which make a small improvement of these properties in both sites. Finally, Different growth parameters (height, covering, fresh and dry matter yield) of the used grasses were clearly positive affected by wood compost, with the highest production inherent to the treatments treated by the high amount of wood compost.}, language = {de} } @phdthesis{Siegmund2022, author = {Siegmund, Nicole}, title = {Wind driven soil particle uptake Quantifying drivers of wind erosion across the particle size spectrum}, doi = {10.25932/publishup-57489}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-574897}, school = {Universit{\"a}t Potsdam}, pages = {ix, 56}, year = {2022}, abstract = {Among the multitude of geomorphological processes, aeolian shaping processes are of special character, Pedogenic dust is one of the most important sources of atmospheric aerosols and therefore regarded as a key player for atmospheric processes. Soil dust emissions, being complex in composition and properties, influence atmospheric processes and air quality and has impacts on other ecosystems. In this because even though their immediate impact can be considered low (exceptions exist), their constant and large-scale force makes them a powerful player in the earth system. dissertation, we unravel a novel scientific understanding of this complex system based on a holistic dataset acquired during a series of field experiments on arable land in La Pampa, Argentina. The field experiments as well as the generated data provide information about topography, various soil parameters, the atmospheric dynamics in the very lower atmosphere (4m height) as well as measurements regarding aeolian particle movement across a wide range of particle size classes between 0.2μm up to the coarse sand. The investigations focus on three topics: (a) the effects of low-scale landscape structures on aeolian transport processes of the coarse particle fraction, (b) the horizontal and vertical fluxes of the very fine particles and (c) the impact of wind gusts on particle emissions. Among other considerations presented in this thesis, it could in particular be shown, that even though the small-scale topology does have a clear impact on erosion and deposition patterns, also physical soil parameters need to be taken into account for a robust statistical modelling of the latter. Furthermore, specifically the vertical fluxes of particulate matter have different characteristics for the particle size classes. Finally, a novel statistical measure was introduced to quantify the impact of wind gusts on the particle uptake and its application on the provided data set. The aforementioned measure shows significantly increased particle concentrations during points in time defined as gust event. With its holistic approach, this thesis further contributes to the fundamental understanding of how atmosphere and pedosphere are intertwined and affect each other.}, language = {en} } @phdthesis{Fuchs2013, author = {Fuchs, Sven}, title = {Well-log based determination of rock thermal conductivity in the North German Basin}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-67801}, school = {Universit{\"a}t Potsdam}, year = {2013}, abstract = {In sedimentary basins, rock thermal conductivity can vary both laterally and vertically, thus altering the basin's thermal structure locally and regionally. Knowledge of the thermal conductivity of geological formations and its spatial variations is essential, not only for quantifying basin evolution and hydrocarbon maturation processes, but also for understanding geothermal conditions in a geological setting. In conjunction with the temperature gradient, thermal conductivity represents the basic input parameter for the determination of the heat-flow density; which, in turn, is applied as a major input parameter in thermal modeling at different scales. Drill-core samples, which are necessary to determine thermal properties by laboratory measurements, are rarely available and often limited to previously explored reservoir formations. Thus, thermal conductivities of Mesozoic rocks in the North German Basin (NGB) are largely unknown. In contrast, geophysical borehole measurements are often available for the entire drilled sequence. Therefore, prediction equations to determine thermal conductivity based on well-log data are desirable. In this study rock thermal conductivity was investigated on different scales by (1) providing thermal-conductivity measurements on Mesozoic rocks, (2) evaluating and improving commonly applied mixing models which were used to estimate matrix and pore-filled rock thermal conductivities, and (3) developing new well-log based equations to predict thermal conductivity in boreholes without core control. Laboratory measurements are performed on sedimentary rock of major geothermal reservoirs in the Northeast German Basin (NEGB) (Aalenian, Rhaethian-Liassic, Stuttgart Fm., and Middle Buntsandstein). Samples are obtained from eight deep geothermal wells that approach depths of up to 2,500 m. Bulk thermal conductivities of Mesozoic sandstones range between 2.1 and 3.9 W/(m∙K), while matrix thermal conductivity ranges between 3.4 and 7.4 W/(m∙K). Local heat flow for the Stralsund location averages 76 mW/m², which is in good agreement to values reported previously for the NEGB. For the first time, in-situ bulk thermal conductivity is indirectly calculated for entire borehole profiles in the NEGB using the determined surface heat flow and measured temperature data. Average bulk thermal conductivity, derived for geological formations within the Mesozoic section, ranges between 1.5 and 3.1 W/(m∙K). The measurement of both dry- and water-saturated thermal conductivities allow further evaluation of different two-component mixing models which are often applied in geothermal calculations (e.g., arithmetic mean, geometric mean, harmonic mean, Hashin-Shtrikman mean, and effective-medium theory mean). It is found that the geometric-mean model shows the best correlation between calculated and measured bulk thermal conductivity. However, by applying new model-dependent correction, equations the quality of fit could be significantly improved and the error diffusion of each model reduced. The 'corrected' geometric mean provides the most satisfying results and constitutes a universally applicable model for sedimentary rocks. Furthermore, lithotype-specific and model-independent conversion equations are developed permitting a calculation of water-saturated thermal conductivity from dry-measured thermal conductivity and porosity within an error range of 5 to 10\%. The limited availability of core samples and the expensive core-based laboratory measurements make it worthwhile to use petrophysical well logs to determine thermal conductivity for sedimentary rocks. The approach followed in this study is based on the detailed analyses of the relationships between thermal conductivity of rock-forming minerals, which are most abundant in sedimentary rocks, and the properties measured by standard logging tools. By using multivariate statistics separately for clastic, carbonate and evaporite rocks, the findings from these analyses allow the development of prediction equations from large artificial data sets that predict matrix thermal conductivity within an error of 4 to 11\%. These equations are validated successfully on a comprehensive subsurface data set from the NGB. In comparison to the application of earlier published approaches formation-dependent developed for certain areas, the new developed equations show a significant error reduction of up to 50\%. These results are used to infer rock thermal conductivity for entire borehole profiles. By inversion of corrected in-situ thermal-conductivity profiles, temperature profiles are calculated and compared to measured high-precision temperature logs. The resulting uncertainty in temperature prediction averages < 5\%, which reveals the excellent temperature prediction capabilities using the presented approach. In conclusion, data and methods are provided to achieve a much more detailed parameterization of thermal models.}, language = {en} } @phdthesis{Endres1997, author = {Endres, Christoph}, title = {Warvenchronologie und Radiokarbondatierungen an holoz{\"a}nen und sp{\"a}tglazialen Sedimenten des Meerfelder Maares, Eifel}, address = {Potsdam}, pages = {98 S. : graph. Darst.}, year = {1997}, language = {de} } @phdthesis{Ruch2010, author = {Ruch, Jo{\"e}l}, title = {Volcano deformation analysis in the Lazufre area (central Andes) using geodetic and geological observations}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-47361}, school = {Universit{\"a}t Potsdam}, year = {2010}, abstract = {Large-scale volcanic deformation recently detected by radar interferometry (InSAR) provides new information and thus new scientific challenges for understanding volcano-tectonic activity and magmatic systems. The destabilization of such a system at depth noticeably affects the surrounding environment through magma injection, ground displacement and volcanic eruptions. To determine the spatiotemporal evolution of the Lazufre volcanic area located in the central Andes, we combined short-term ground displacement acquired by InSAR with long-term geological observations. Ground displacement was first detected using InSAR in 1997. By 2008, this displacement affected 1800 km2 of the surface, an area comparable in size to the deformation observed at caldera systems. The original displacement was followed in 2000 by a second, small-scale, neighbouring deformation located on the Lastarria volcano. We performed a detailed analysis of the volcanic structures at Lazufre and found relationships with the volcano deformations observed with InSAR. We infer that these observations are both likely to be the surface expression of a long-lived magmatic system evolving at depth. It is not yet clear whether Lazufre may trigger larger unrest or volcanic eruptions; however, the second deformation detected at Lastarria and the clear increase of the large-scale deformation rate make this an area of particular interest for closer continuous monitoring.}, language = {en} } @phdthesis{Zali2023, author = {Zali, Zahra}, title = {Volcanic tremor analysis based on advanced signal processing concepts including music information retrieval (MIR) strategies}, doi = {10.25932/publishup-61086}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-610866}, school = {Universit{\"a}t Potsdam}, pages = {viii, 95}, year = {2023}, abstract = {Volcanoes are one of the Earth's most dynamic zones and responsible for many changes in our planet. Volcano seismology aims to provide an understanding of the physical processes in volcanic systems and anticipate the style and timing of eruptions by analyzing the seismic records. Volcanic tremor signals are usually observed in the seismic records before or during volcanic eruptions. Their analysis contributes to evaluate the evolving volcanic activity and potentially predict eruptions. Years of continuous seismic monitoring now provide useful information for operational eruption forecasting. The continuously growing amount of seismic recordings, however, poses a challenge for analysis, information extraction, and interpretation, to support timely decision making during volcanic crises. Furthermore, the complexity of eruption processes and precursory activities makes the analysis challenging. A challenge in studying seismic signals of volcanic origin is the coexistence of transient signal swarms and long-lasting volcanic tremor signals. Separating transient events from volcanic tremors can, therefore, contribute to improving our understanding of the underlying physical processes. Some similar issues (data reduction, source separation, extraction, and classification) are addressed in the context of music information retrieval (MIR). The signal characteristics of acoustic and seismic recordings comprise a number of similarities. This thesis is going beyond classical signal analysis techniques usually employed in seismology by exploiting similarities of seismic and acoustic signals and building the information retrieval strategy on the expertise developed in the field of MIR. First, inspired by the idea of harmonic-percussive separation (HPS) in musical signal processing, I have developed a method to extract harmonic volcanic tremor signals and to detect transient events from seismic recordings. This provides a clean tremor signal suitable for tremor investigation along with a characteristic function suitable for earthquake detection. Second, using HPS algorithms, I have developed a noise reduction technique for seismic signals. This method is especially useful for denoising ocean bottom seismometers, which are highly contaminated by noise. The advantage of this method compared to other denoising techniques is that it doesn't introduce distortion to the broadband earthquake waveforms, which makes it reliable for different applications in passive seismological analysis. Third, to address the challenge of extracting information from high-dimensional data and investigating the complex eruptive phases, I have developed an advanced machine learning model that results in a comprehensive signal processing scheme for volcanic tremors. Using this method seismic signatures of major eruptive phases can be automatically detected. This helps to provide a chronology of the volcanic system. Also, this model is capable to detect weak precursory volcanic tremors prior to the eruption, which could be used as an indicator of imminent eruptive activity. The extracted patterns of seismicity and their temporal variations finally provide an explanation for the transition mechanism between eruptive phases.}, language = {en} } @phdthesis{Hinrichsen1999, author = {Hinrichsen, Arne}, title = {Vergleichend-{\"o}kologische Untersuchung {\"u}ber Konversionsgebiete in Brandenburg als Lebensraum solit{\"a}rer Wespen (Hymenoptera Aculeata) mit besonderer Ber{\"u}cksichtigung der Sukzessionsfolgen}, address = {Potsdam}, pages = {V, 145 Bl. : graph. Darst., Ill., Kt.}, year = {1999}, language = {de} } @phdthesis{Niemeyer2016, author = {Niemeyer, Bastian}, title = {Vegetation reconstruction and assessment of plant diversity at the treeline ecotone in northern Siberia}, school = {Universit{\"a}t Potsdam}, pages = {146}, year = {2016}, language = {en} }