TY - GEN A1 - Su, Yingna A1 - Kliem, Bernhard A1 - van Ballegooijen, Adriaan A1 - Deluca, Edward T1 - Numerical simulations of the CME on 2010 April 8 T2 - Solar and Astrophysical Dynamos and Magnetic Activity N2 - We present 3D zero-beta ideal MHD simulations of the solar flare/CME event that occurred in Active Region 11060 on 2010 April 8. The initial magnetic configurations of the two simulations are stable nonlinear force-free field and unstable magnetic field models constructed by Su et al. (2011) using the flux rope insertion method. The MHD simulations confirm that the stable model relaxes to a stable equilibrium, while the unstable model erupts as a CME. Comparisons between observations and MHD simulations of the CME are also presented. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 674 KW - Sun: coronal mass ejections (CMEs) KW - Sun: flares KW - Sun: magnetic fields Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-414887 SN - 1866-8372 IS - 674 SP - 575 EP - 576 ER - TY - GEN A1 - Zibulski, Romy A1 - Wesener, Felix A1 - Wilkes, Heinz A1 - Plessen, Birgit A1 - Pestryakova, Luidmila Agafyevna A1 - Herzschuh, Ulrike T1 - C / N ratio, stable isotope (δ 13 C, δ 15 N), and n-alkane patterns of brown mosses along hydrological gradients of low-centred polygons of the Siberian Arctic T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Mosses are a major component of the arctic vegetation, particularly in wetlands. We present C / N atomic ratio, delta C-13 and delta N-15 data of 400 brown-moss samples belonging to 10 species that were collected along hydrological gradients within polygonal mires located on the southern Taymyr Peninsula and the Lena River delta in northern Siberia. Additionally, n-alkane patterns of six of these species (16 samples) were investigated. The aim of the study is to see whether the inter-and intraspecific differences in C / N, isotopic compositions and n-alkanes are indicative of habitat, particularly with respect to water level. Overall, we find high variability in all investigated parameters for two different moisture-related groups of moss species. The C / N ratios range between 11 and 53 (median: 32) and show large variations at the intraspecific level. However, species preferring a dry habitat (xero-mesophilic mosses) show higher C / N ratios than those preferring a wet habitat (meso-hygrophilic mosses). The delta C-13 values range between 37.0 and 22.5% (median D 27.8 %). The delta N-15 values range between 6.6 and C 1.7%(median D 2.2 %). We find differences in delta C-13 and delta N-15 compositions between both habitat types. For some species of the meso-hygrophilic group, we suggest that a relationship between the individ-ual habitat water level and isotopic composition can be inferred as a function of microbial symbiosis. The n-alkane distribution also shows differences primarily between xeromesophilic and meso-hygrophilic mosses, i. e. having a dominance of n-alkanes with long (n-C29, n-C31 /and intermediate (n-C25 /chain lengths, respectively. Overall, our results reveal that C / N ratios, isotopic signals and n-alkanes of studied brown-moss taxa from polygonal wetlands are characteristic of their habitat. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 672 KW - atmospheric nitrogen deposition KW - Lena River delta KW - free amino-acids KW - ombrotrophic peat KW - carbon isotopes KW - aquatic macrophytes KW - methane oxidation KW - organic matter KW - soil-nitrogen KW - plants Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-417104 SN - 1866-8372 IS - 672 ER - TY - GEN A1 - Nord, Guillaume A1 - Boudevillain, Brice A1 - Berne, Alexis A1 - Branger, Flora A1 - Braud, Isabelle A1 - Dramais, Guillaume A1 - Gérard, Simon A1 - Le Coz, Jérôme A1 - Legoût, Cédric A1 - Molinié, Gilles A1 - Van Baelen, Joel A1 - Vandervaere, Jean-Pierre A1 - Andrieu, Julien A1 - Aubert, Coralie A1 - Calianno, Martin A1 - Delrieu, Guy A1 - Grazioli, Jacopo A1 - Hachani, Sahar A1 - Horner, Ivan A1 - Huza, Jessica A1 - Le Boursicaud, Raphaël A1 - Raupach, Timothy H. A1 - Teuling, Adriaan J. A1 - Uber, Magdalena A1 - Vincendon, Béatrice A1 - Wijbrans, Annette T1 - A high space–time resolution dataset linking meteorological forcing and hydro-sedimentary response in a mesoscale Mediterranean catchment (Auzon) of the Ardèche region, France T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - A comprehensive hydrometeorological dataset is presented spanning the period 1 January 201131 December 2014 to improve the understanding of the hydrological processes leading to flash floods and the relation between rainfall, runoff, erosion and sediment transport in a mesoscale catchment (Auzon, 116 km(2)) of the Mediterranean region. Badlands are present in the Auzon catchment and well connected to high-gradient channels of bedrock rivers which promotes the transfer of suspended solids downstream. The number of observed variables, the various sensors involved (both in situ and remote) and the space-time resolution (similar to km(2), similar to min) of this comprehensive dataset make it a unique contribution to research communities focused on hydrometeorology, surface hydrology and erosion. Given that rainfall is highly variable in space and time in this region, the observation system enables assessment of the hydrological response to rainfall fields. Indeed, (i) rainfall data are provided by rain gauges (both a research network of 21 rain gauges with a 5 min time step and an operational network of 10 rain gauges with a 5 min or 1 h time step), S-band Doppler dual-polarization radars (1 km(2), 5 min resolution), disdrometers (16 sensors working at 30 s or 1 min time step) and Micro Rain Radars (5 sensors, 100m height resolution). Additionally, during the special observation period (SOP-1) of the HyMeX (Hydrological Cycle in the Mediterranean Experiment) project, two X-band radars provided precipitation measurements at very fine spatial and temporal scales (1 ha, 5 min). (ii) Other meteorological data are taken from the operational surface weather observation stations of Meteo-France (including 2m air temperature, atmospheric pressure, 2 m relative humidity, 10m wind speed and direction, global radiation) at the hourly time resolution (six stations in the region of interest). (iii) The monitoring of surface hydrology and suspended sediment is multi-scale and based on nested catchments. Three hydrometric stations estimate water discharge at a 2-10 min time resolution. Two of these stations also measure additional physico-chemical variables (turbidity, temperature, conductivity) and water samples are collected automatically during floods, allowing further geochemical characterization of water and suspended solids. Two experimental plots monitor overland flow and erosion at 1 min time resolution on a hillslope with vineyard. A network of 11 sensors installed in the intermittent hydrographic network continuously measures water level and water temperature in headwater subcatchments (from 0.17 to 116 km(2)) at a time resolution of 2-5 min. A network of soil moisture sensors enables the continuous measurement of soil volumetric water content at 20 min time resolution at 9 sites. Additionally, concomitant observations (soil moisture measurements and stream gauging) were performed during floods between 2012 and 2014. Finally, this dataset is considered appropriate for understanding the rainfall variability in time and space at fine scales, improving areal rainfall estimations and progressing in distributed hydrological and erosion modelling. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 671 KW - hydraulic properties KW - soil moisture KW - flash floods KW - rainfall KW - radar KW - scale KW - variability KW - transport KW - erosion KW - model Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-419127 SN - 1866-8372 IS - 671 ER - TY - GEN A1 - Zimmermann, Heike Hildegard A1 - Raschke, Elena A1 - Epp, Laura Saskia A1 - Stoof-Leichsenring, Kathleen Rosemarie A1 - Schwamborn, Georg A1 - Schirrmeister, Lutz A1 - Overduin, Pier Paul A1 - Herzschuh, Ulrike T1 - Sedimentary ancient DNA and pollen reveal the composition of plant organic matter in Late Quaternary permafrost sediments of the Buor Khaya Peninsula (north-eastern Siberia) T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Organic matter deposited in ancient, ice-rich permafrost sediments is vulnerable to climate change and may contribute to the future release of greenhouse gases; it is thus important to get a better characterization of the plant organic matter within such sediments. From a Late Quaternary permafrost sediment core from the Buor Khaya Peninsula, we analysed plant-derived sedimentary ancient DNA (sedaDNA) to identify the taxonomic composition of plant organic matter, and undertook palynological analysis to assess the environmental conditions during deposition. Using sedaDNA, we identified 154 taxa and from pollen and non-pollen palynomorphs we identified 83 taxa. In the deposits dated between 54 and 51 kyr BP, sedaDNA records a diverse low-centred polygon plant community including recurring aquatic pond vegetation while from the pollen record we infer terrestrial open-land vegetation with relatively dry environmental conditions at a regional scale. A fluctuating dominance of either terrestrial or swamp and aquatic taxa in both proxies allowed the local hydrological development of the polygon to be traced. In deposits dated between 11.4 and 9.7 kyr BP (13.4-11.1 cal kyr BP), sedaDNA shows a taxonomic turnover to moist shrub tundra and a lower taxonomic richness compared to the older samples. Pollen also records a shrub tundra community, mostly seen as changes in relative proportions of the most dominant taxa, while a decrease in taxonomic richness was less pronounced compared to sedaDNA. Our results show the advantages of using sedaDNA in combination with palynological analyses when macrofossils are rarely preserved. The high resolution of the sedaDNA record provides a detailed picture of the taxonomic composition of plant-derived organic matter throughout the core, and palynological analyses prove valuable by allowing for inferences of regional environmental conditions. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 670 KW - NE Siberia KW - vegetation patterns KW - environmental DNA KW - Arctic vegetation KW - frozen sediments KW - lake-sediments KW - gas-production KW - carbon KW - polygon KW - climate Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-417130 SN - 1866-8372 IS - 670 ER - TY - GEN A1 - Biskaborn, Boris A1 - Smith, Sharon L. A1 - Noetzli, Jeannette A1 - Matthes, Heidrun A1 - Vieira, Gonçalo A1 - Streletskiy, Dmitry A. A1 - Schoeneich, Philippe A1 - Romanovsky, Vladimir E. A1 - Lewkowicz, Antoni G. A1 - Abramov, Andrey A1 - Allard, Michel A1 - Boike, Julia A1 - Cable, William L. A1 - Christiansen, Hanne H. A1 - Delaloye, Reynald A1 - Diekmann, Bernhard A1 - Drozdov, Dmitry A1 - Etzelmüller, Bernd A1 - Große, Guido A1 - Guglielmin, Mauro A1 - Ingeman-Nielsen, Thomas A1 - Isaksen, Ketil A1 - Ishikawa, Mamoru A1 - Johansson, Margareta A1 - Joo, Anseok A1 - Kaverin, Dmitry A1 - Kholodov, Alexander A1 - Konstantinov, Pavel A1 - Kröger, Tim A1 - Lambiel, Christophe A1 - Lanckman, Jean-Pierre A1 - Luo, Dongliang A1 - Malkova, Galina A1 - Meiklejohn, Ian A1 - Moskalenko, Natalia A1 - Oliva, Marc A1 - Phillips, Marcia A1 - Ramos, Miguel A1 - Sannel, A. Britta K. A1 - Sergeev, Dmitrii A1 - Seybold, Cathy A1 - Skryabin, Pavel A1 - Vasiliev, Alexander A1 - Wu, Qingbai A1 - Yoshikawa, Kenji A1 - Zheleznyak, Mikhail A1 - Lantuit, Hugues T1 - Permafrost is warming at a global scale T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Permafrost warming has the potential to amplify global climate change, because when frozen sediments thaw it unlocks soil organic carbon. Yet to date, no globally consistent assessment of permafrost temperature change has been compiled. Here we use a global data set of permafrost temperature time series from the Global Terrestrial Network for Permafrost to evaluate temperature change across permafrost regions for the period since the International Polar Year (2007–2009). During the reference decade between 2007 and 2016, ground temperature near the depth of zero annual amplitude in the continuous permafrost zone increased by 0.39 ± 0.15 °C. Over the same period, discontinuous permafrost warmed by 0.20 ± 0.10 °C. Permafrost in mountains warmed by 0.19 ± 0.05 °C and in Antarctica by 0.37 ± 0.10 °C. Globally, permafrost temperature increased by 0.29 ± 0.12 °C. The observed trend follows the Arctic amplification of air temperature increase in the Northern Hemisphere. In the discontinuous zone, however, ground warming occurred due to increased snow thickness while air temperature remained statistically unchanged. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 669 KW - seasonal snow cover KW - thermal state KW - climate-change KW - activ-layer KW - Antarctic Peninsula KW - stability Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-425341 SN - 1866-8372 IS - 669 ER - TY - GEN A1 - Young, Linda A1 - Ueda, Kiyoshi A1 - Gühr, Markus A1 - Bucksbaum, Philip H. A1 - Simon, Marc A1 - Mukamel, Shaul A1 - Rohringer, Nina A1 - Prince, Kevin C. A1 - Masciovecchio, Claudio A1 - Meyer, Michael A1 - Rudenko, Artem A1 - Rolles, Daniel A1 - Bostedt, Christoph A1 - Fuchs, Matthias A1 - Reis, David A. A1 - Santra, Robin A1 - Kapteyn, Henry A1 - Murnane, Margaret A1 - Ibrahim, Heide A1 - Légaré, François A1 - Vrakking, Marc A1 - Isinger, Marcus A1 - Kroon, David A1 - Gisselbrecht, Mathieu A1 - L'Huillier, Anne A1 - Wörner, Hans Jakob A1 - Leone, Stephen R. T1 - Roadmap of ultrafast x-ray atomic and molecular physics T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - X-ray free-electron lasers (XFELs) and table-top sources of x-rays based upon high harmonic generation (HHG) have revolutionized the field of ultrafast x-ray atomic and molecular physics, largely due to an explosive growth in capabilities in the past decade. XFELs now provide unprecedented intensity (1020 W cm−2) of x-rays at wavelengths down to ~1 Ångstrom, and HHG provides unprecedented time resolution (~50 attoseconds) and a correspondingly large coherent bandwidth at longer wavelengths. For context, timescales can be referenced to the Bohr orbital period in hydrogen atom of 150 attoseconds and the hydrogen-molecule vibrational period of 8 femtoseconds; wavelength scales can be referenced to the chemically significant carbon K-edge at a photon energy of ~280 eV (44 Ångstroms) and the bond length in methane of ~1 Ångstrom. With these modern x-ray sources one now has the ability to focus on individual atoms, even when embedded in a complex molecule, and view electronic and nuclear motion on their intrinsic scales (attoseconds and Ångstroms). These sources have enabled coherent diffractive imaging, where one can image non-crystalline objects in three dimensions on ultrafast timescales, potentially with atomic resolution. The unprecedented intensity available with XFELs has opened new fields of multiphoton and nonlinear x-ray physics where behavior of matter under extreme conditions can be explored. The unprecedented time resolution and pulse synchronization provided by HHG sources has kindled fundamental investigations of time delays in photoionization, charge migration in molecules, and dynamics near conical intersections that are foundational to AMO physics and chemistry. This roadmap coincides with the year when three new XFEL facilities, operating at Ångstrom wavelengths, opened for users (European XFEL, Swiss-FEL and PAL-FEL in Korea) almost doubling the present worldwide number of XFELs, and documents the remarkable progress in HHG capabilities since its discovery roughly 30 years ago, showcasing experiments in AMO physics and other applications. Here we capture the perspectives of 17 leading groups and organize the contributions into four categories: ultrafast molecular dynamics, multidimensional x-ray spectroscopies; high-intensity x-ray phenomena; attosecond x-ray science. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 668 KW - ultrafast molecular dynamics KW - x-ray spectroscopies and phenomena KW - table-top sources KW - x-ray free-electron lasers KW - attosecond phenomena Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-424238 SN - 1866-8372 IS - 668 ER - TY - GEN A1 - Hornick, Thomas A1 - Bach, Lennart T. A1 - Crawfurd, Katharine J. A1 - Spilling, Kristian A1 - Achterberg, Eric Pieter A1 - Woodhouse, Jason Nicholas A1 - Schulz, Kai Georg A1 - Brussaard, Corina P. D. A1 - Riebesell, Ulf A1 - Grossart, Hans-Peter T1 - Ocean acidification impacts bacteria–phytoplankton coupling at low-nutrient conditions T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - The oceans absorb about a quarter of the annually produced anthropogenic atmospheric carbon dioxide (CO2), resulting in a decrease in surface water pH, a process termed ocean acidification (OA). Surprisingly little is known about how OA affects the physiology of heterotrophic bacteria or the coupling of heterotrophic bacteria to phytoplankton when nutrients are limited. Previous experiments were, for the most part, undertaken during productive phases or following nutrient additions designed to stimulate algal blooms. Therefore, we performed an in situ large-volume mesocosm (similar to 55 m(3)) experiment in the Baltic Sea by simulating different fugacities of CO2 (fCO(2)) extending from present to future conditions. The study was conducted in July-August after the nominal spring bloom, in order to maintain low-nutrient conditions throughout the experiment. This resulted in phytoplankton communities dominated by small-sized functional groups (picophytoplankton). There was no consistent fCO(2)-induced effect on bacterial protein production (BPP), cell-specific BPP (csBPP) or biovolumes (BVs) of either free-living (FL) or particle-associated (PA) heterotrophic bacteria, when considered as individual components (univariate analyses). Permutational Multivariate Analysis of Variance (PERMANOVA) revealed a significant effect of the fCO(2) treatment on entire assemblages of dissolved and particulate nutrients, metabolic parameters and the bacteria-phytoplankton community. However, distance-based linear modelling only identified fCO(2) as a factor explaining the variability observed amongst the microbial community composition, but not for explaining variability within the metabolic parameters. This suggests that fCO(2) impacts on microbial metabolic parameters occurred indirectly through varying physicochemical parameters and microbial species composition. Cluster analyses examining the co-occurrence of different functional groups of bacteria and phytoplankton further revealed a separation of the four fCO(2)-treated mesocosms from both control mesocosms, indicating that complex trophic interactions might be altered in a future acidified ocean. Possible consequences for nutrient cycling and carbon export are still largely unknown, in particular in a nutrient-limited ocean. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 667 KW - northern Baltic Sea KW - inorganic nutrients KW - mesocosm experiment KW - elevated CO2 KW - heterotrophic bacteria KW - organic-carbon KW - bacterioplankton KW - seawater KW - growth KW - temperature Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-417126 SN - 1866-8372 IS - 667 ER - TY - GEN A1 - Hoffmann, Mathias A1 - Jurisch, Nicole A1 - Alba, Juana Garcia A1 - Borraz, Elisa Albiac A1 - Schmidt, Marten A1 - Huth, Vytas A1 - Rogasik, Helmut A1 - Rieckh, Helene A1 - Verch, Gernot A1 - Sommer, Michael A1 - Augustin, Jürgen T1 - Detecting small-scale spatial heterogeneity and temporal dynamics of soil organic carbon (SOC) stocks BT - a comparison between automatic chamber-derived C budgets and repeated soil inventories T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Carbon (C) sequestration in soils plays a key role in the global C cycle. It is therefore crucial to adequately monitor dynamics in soil organic carbon (Delta SOC) stocks when aiming to reveal underlying processes and potential drivers. However, small-scale spatial (10-30 m) and temporal changes in SOC stocks, particularly pronounced in arable lands, are hard to assess. The main reasons for this are limitations of the well-established methods. On the one hand, repeated soil inventories, often used in long-term field trials, reveal spatial patterns and trends in Delta SOC but require a longer observation period and a sufficient number of repetitions. On the other hand, eddy covariance measurements of C fluxes towards a complete C budget of the soil-plant-atmosphere system may help to obtain temporal Delta SOC patterns but lack small-scale spatial resolution. To overcome these limitations, this study presents a reliable method to detect both short-term temporal dynamics as well as small-scale spatial differences of Delta SOC using measurements of the net ecosystem carbon balance (NECB) as a proxy. To estimate the NECB, a combination of automatic chamber (AC) measurements of CO2 exchange and empirically modeled aboveground biomass development (NPPshoot / were used. To verify our method, results were compared with Delta SOC observed by soil resampling. Soil resampling and AC measurements were performed from 2010 to 2014 at a colluvial depression located in the hummocky ground moraine landscape of northeastern Germany. The measurement site is characterized by a variable groundwater level (GWL) and pronounced small-scale spatial heterogeneity regarding SOC and nitrogen (Nt) stocks. Tendencies and magnitude of Delta SOC values derived by AC measurements and repeated soil inventories corresponded well. The period of maximum plant growth was identified as being most important for the development of spatial differences in annual Delta SOC. Hence, we were able to confirm that AC-based C budgets are able to reveal small-scale spatial differences and short-term temporal dynamics of Delta SOC. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 666 KW - net ecosystem exchange KW - North Central region KW - no-till ecosystem KW - eddy covariance KW - CO2 fluxes KW - dioxide exchange KW - United States KW - gas-exchange KW - agricultural landscapes KW - monitoring networks Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-417118 SN - 1866-8372 IS - 666 ER - TY - GEN A1 - Jackisch, Conrad A1 - Angermann, Lisa A1 - Allroggen, Niklas A1 - Sprenger, Matthias A1 - Blume, Theresa A1 - Tronicke, Jens A1 - Zehe, Erwin T1 - Form and function in hillslope hydrology BT - in situ imaging and characterization of flow-relevant structures T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - The study deals with the identification and characterization of rapid subsurface flow structures through pedo- and geo-physical measurements and irrigation experiments at the point, plot and hillslope scale. Our investigation of flow-relevant structures and hydrological responses refers to the general interplay of form and function, respectively. To obtain a holistic picture of the subsurface, a large set of different laboratory, exploratory and experimental methods was used at the different scales. For exploration these methods included drilled soil core profiles, in situ measurements of infiltration capacity and saturated hydraulic conductivity, and laboratory analyses of soil water retention and saturated hydraulic conductivity. The irrigation experiments at the plot scale were monitored through a combination of dye tracer, salt tracer, soil moisture dynamics, and 3-D time-lapse ground penetrating radar (GPR) methods. At the hillslope scale the subsurface was explored by a 3-D GPR survey. A natural storm event and an irrigation experiment were monitored by a dense network of soil moisture observations and a cascade of 2-D time-lapse GPR "trenches". We show that the shift between activated and non-activated state of the flow paths is needed to distinguish structures from overall heterogeneity. Pedo-physical analyses of point-scale samples are the basis for sub-scale structure inference. At the plot and hillslope scale 3-D and 2-D time-lapse GPR applications are successfully employed as non-invasive means to image subsurface response patterns and to identify flow-relevant paths. Tracer recovery and soil water responses from irrigation experiments deliver a consistent estimate of response velocities. The combined observation of form and function under active conditions provides the means to localize and characterize the structures (this study) and the hydrological processes (companion study Angermann et al., 2017, this issue). T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 665 KW - Ground Penetrating Radar KW - preferential flow KW - solute transport KW - Catchment Hydrology KW - multiple scales KW - soil moisture KW - water content KW - tracer KW - field KW - model Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-419188 SN - 1866-8372 IS - 665 ER - TY - GEN A1 - Campforts, Benjamin A1 - Schwanghart, Wolfgang A1 - Govers, Gerard T1 - Accurate simulation of transient landscape evolution by eliminating numerical diffusion BT - the TTLEM 1.0 model T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Landscape evolution models (LEMs) allow the study of earth surface responses to changing climatic and tectonic forcings. While much effort has been devoted to the development of LEMs that simulate a wide range of processes, the numerical accuracy of these models has received less attention. Most LEMs use first-order accurate numerical methods that suffer from substantial numerical diffusion. Numerical diffusion particularly affects the solution of the advection equation and thus the simulation of retreating landforms such as cliffs and river knickpoints. This has potential consequences for the integrated response of the simulated landscape. Here we test a higher-order flux-limiting finite volume method that is total variation diminishing (TVD-FVM) to solve the partial differential equations of river incision and tectonic displacement. We show that using the TVD-FVM to simulate river incision significantly influences the evolution of simulated landscapes and the spatial and temporal variability of catchment-wide erosion rates. Furthermore, a two-dimensional TVD-FVM accurately simulates the evolution of landscapes affected by lateral tectonic displacement, a process whose simulation was hitherto largely limited to LEMs with flexible spatial discretization. We implement the scheme in TTLEM (TopoToolbox Landscape Evolution Model), a spatially explicit, raster-based LEM for the study of fluvially eroding landscapes in TopoToolbox 2. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 664 KW - stream power law KW - river incision model KW - transport KW - topography KW - hillslopes KW - equation KW - implicit KW - erosion KW - ranges Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-418784 SN - 1866-8372 IS - 664 ER -