@techreport{BrodeurMikolaCooketal.2024, type = {Working Paper}, author = {Brodeur, Abel and Mikola, Derek and Cook, Nikolai and Brailey, Thomas and Briggs, Ryan and Gendre, Alexandra de and Dupraz, Yannick and Fiala, Lenka and Gabani, Jacopo and Gauriot, Romain and Haddad, Joanne and Lima, Goncalo and Ankel-Peters, J{\"o}rg and Dreber, Anna and Campbell, Douglas and Kattan, Lamis and Fages, Diego Marino and Mierisch, Fabian and Sun, Pu and Wright, Taylor and Connolly, Marie and Hoces de la Guardia, Fernando and Johannesson, Magnus and Miguel, Edward and Vilhuber, Lars and Abarca, Alejandro and Acharya, Mahesh and Adjisse, Sossou Simplice and Akhtar, Ahwaz and Lizardi, Eduardo Alberto Ramirez and Albrecht, Sabina and Andersen, Synve Nygaard and Andlib, Zubaria and Arrora, Falak and Ash, Thomas and Bacher, Etienne and Bachler, Sebastian and Bacon, F{\´e}lix and Bagues, Manuel and Balogh, Timea and Batmanov, Alisher and Barschkett, Mara and Basdil, B. Kaan and Dower, Jaromneda and Castek, Ondrej and Caviglia-Harris, Jill and Strand, Gabriella Chauca and Chen, Shi and Chzhen, Asya and Chung, Jong and Collins, Jason and Coppock, Alexander and Cordeau, Hugo and Couillard, Ben and Crechet, Jonathan and Crippa, Lorenzo and Cui, Jeanne and Czymara, Christian and Daarstad, Haley and Dao, Danh Chi and Dao, Dong and Schmandt, Marco David and Linde, Astrid de and Melo, Lucas De and Deer, Lachlan and Vera, Micole De and Dimitrova, Velichka and Dollbaum, Jan Fabian and Dollbaum, Jan Matti and Donnelly, Michael and Huynh, Luu Duc Toan and Dumbalska, Tsvetomira and Duncan, Jamie and Duong, Kiet Tuan and Duprey, Thibaut and Dworschak, Christoph and Ellingsrud, Sigmund and Elminejad, Ali and Eissa, Yasmine and Erhart, Andrea and Etingin-Frati, Giulian and Fatemi-Pour, Elaheh and Federice, Alexa and Feld, Jan and Fenig, Guidon and Firouzjaeiangalougah, Mojtaba and Fleisje, Erlend and Fortier-Chouinard, Alexandre and Engel, Julia Francesca and Fries, Tilman and Fortier, Reid and Fr{\´e}chet, Nadjim and Galipeau, Thomas and Gallegos, Sebasti{\´a}n and Gangji, Areez and Gao, Xiaoying and Garnache, Clo{\´e} and G{\´a}sp{\´a}r, Attila and Gavrilova, Evelina and Ghosh, Arijit and Gibney, Garreth and Gibson, Grant and Godager, Geir and Goff, Leonard and Gong, Da and Gonz{\´a}lez, Javier and Gretton, Jeremy and Griffa, Cristina and Grigoryeva, Idaliya and Grtting, Maja and Guntermann, Eric and Guo, Jiaqi and Gugushvili, Alexi and Habibnia, Hooman and H{\"a}ffner, Sonja and Hall, Jonathan D. and Hammar, Olle and Kordt, Amund Hanson and Hashimoto, Barry and Hartley, Jonathan S. and Hausladen, Carina I. and Havr{\´a}nek, Tom{\´a}š and Hazen, Jacob and He, Harry and Hepplewhite, Matthew and Herrera-Rodriguez, Mario and Heuer, Felix and Heyes, Anthony and Ho, Anson T. Y. and Holmes, Jonathan and Holzknecht, Armando and Hsu, Yu-Hsiang Dexter and Hu, Shiang-Hung and Huang, Yu-Shiuan and Huebener, Mathias and Huber, Christoph and Huynh, Kim P. and Irsova, Zuzana and Isler, Ozan and Jakobsson, Niklas and Frith, Michael James and Jananji, Rapha{\"e}l and Jayalath, Tharaka A. and Jetter, Michael and John, Jenny and Forshaw, Rachel Joy and Juan, Felipe and Kadriu, Valon and Karim, Sunny and Kelly, Edmund and Dang, Duy Khanh Hoang and Khushboo, Tazia and Kim, Jin and Kjellsson, Gustav and Kjelsrud, Anders and Kotsadam, Andreas and Korpershoek, Jori and Krashinsky, Lewis and Kundu, Suranjana and Kustov, Alexander and Lalayev, Nurlan and Langlois, Audr{\´e}e and Laufer, Jill and Lee-Whiting, Blake and Leibing, Andreas and Lenz, Gabriel and Levin, Joel and Li, Peng and Li, Tongzhe and Lin, Yuchen and Listo, Ariel and Liu, Dan and Lu, Xuewen and Lukmanova, Elvina and Luscombe, Alex and Lusher, Lester R. and Lyu, Ke and Ma, Hai and M{\"a}der, Nicolas and Makate, Clifton and Malmberg, Alice and Maitra, Adit and Mandas, Marco and Marcus, Jan and Margaryan, Shushanik and M{\´a}rk, Lili and Martignano, Andres and Marsh, Abigail and Masetto, Isabella and McCanny, Anthony and McManus, Emma and McWay, Ryan and Metson, Lennard and Kinge, Jonas Minet and Mishra, Sumit and Mohnen, Myra and M{\"o}ller, Jakob and Montambeault, Rosalie and Montpetit, S{\´e}bastien and Morin, Louis-Philippe and Morris, Todd and Moser, Scott and Motoki, Fabio and Muehlenbachs, Lucija and Musulan, Andreea and Musumeci, Marco and Nabin, Munirul and Nchare, Karim and Neubauer, Florian and Nguyen, Quan M. P. and Nguyen, Tuan and Nguyen-Tien, Viet and Niazi, Ali and Nikolaishvili, Giorgi and Nordstrom, Ardyn and N{\"u}, Patrick and Odermatt, Angela and Olson, Matt and ien, Henning and {\"O}lkers, Tim and Vert, Miquel Oliver i. and Oral, Emre and Oswald, Christian and Ousman, Ali and {\"O}zak, {\"O}mer and Pandey, Shubham and Pavlov, Alexandre and Pelli, Martino and Penheiro, Romeo and Park, RyuGyung and Martel, Eva P{\´e}rez and Petrovičov{\´a}, Tereza and Phan, Linh and Prettyman, Alexa and Proch{\´a}zka, Jakub and Putri, Aqila and Quandt, Julian and Qiu, Kangyu and Nguyen, Loan Quynh Thi and Rahman, Andaleeb and Rea, Carson H. and Reiremo, Adam and Ren{\´e}e, La{\"e}titia and Richardson, Joseph and Rivers, Nicholas and Rodrigues, Bruno and Roelofs, William and Roemer, Tobias and Rogeberg, Ole and Rose, Julian and Roskos-Ewoldsen, Andrew and Rosmer, Paul and Sabada, Barbara and Saberian, Soodeh and Salamanca, Nicolas and Sator, Georg and Sawyer, Antoine and Scates, Daniel and Schl{\"u}ter, Elmar and Sells, Cameron and Sen, Sharmi and Sethi, Ritika and Shcherbiak, Anna and Sogaolu, Moyosore and Soosalu, Matt and Srensen, Erik and Sovani, Manali and Spencer, Noah and Staubli, Stefan and Stans, Renske and Stewart, Anya and Stips, Felix and Stockley, Kieran and Strobel, Stephenson and Struby, Ethan and Tang, John and Tanrisever, Idil and Yang, Thomas Tao and Tastan, Ipek and Tatić, Dejan and Tatlow, Benjamin and Seuyong, F{\´e}raud Tchuisseu and Th{\´e}riault, R{\´e}mi and Thivierge, Vincent and Tian, Wenjie and Toma, Filip-Mihai and Totarelli, Maddalena and Tran, Van-Anh and Truong, Hung and Tsoy, Nikita and Tuzcuoglu, Kerem and Ubfal, Diego and Villalobos, Laura and Walterskirchen, Julian and Wang, Joseph Taoyi and Wattal, Vasudha and Webb, Matthew D. and Weber, Bryan and Weisser, Reinhard and Weng, Wei-Chien and Westheide, Christian and White, Kimberly and Winter, Jacob and Wochner, Timo and Woerman, Matt and Wong, Jared and Woodard, Ritchie and Wroński, Marcin and Yazbeck, Myra and Yang, Gustav Chung and Yap, Luther and Yassin, Kareman and Ye, Hao and Yoon, Jin Young and Yurris, Chris and Zahra, Tahreen and Zaneva, Mirela and Zayat, Aline and Zhang, Jonathan and Zhao, Ziwei and Yaolang, Zhong}, title = {Mass reproducibility and replicability}, series = {I4R discussion paper series}, journal = {I4R discussion paper series}, number = {107}, publisher = {Institute for Replication}, address = {Essen}, issn = {2752-1931}, pages = {250}, year = {2024}, abstract = {This study pushes our understanding of research reliability by reproducing and replicating claims from 110 papers in leading economic and political science journals. The analysis involves computational reproducibility checks and robustness assessments. It reveals several patterns. First, we uncover a high rate of fully computationally reproducible results (over 85\%). Second, excluding minor issues like missing packages or broken pathways, we uncover coding errors for about 25\% of studies, with some studies containing multiple errors. Third, we test the robustness of the results to 5,511 re-analyses. We find a robustness reproducibility of about 70\%. Robustness reproducibility rates are relatively higher for re-analyses that introduce new data and lower for re-analyses that change the sample or the definition of the dependent variable. Fourth, 52\% of re-analysis effect size estimates are smaller than the original published estimates and the average statistical significance of a re-analysis is 77\% of the original. Lastly, we rely on six teams of researchers working independently to answer eight additional research questions on the determinants of robustness reproducibility. Most teams find a negative relationship between replicators' experience and reproducibility, while finding no relationship between reproducibility and the provision of intermediate or even raw data combined with the necessary cleaning codes.}, language = {en} } @article{SchroederFuerstKlasenetal.2000, author = {Schr{\"o}der, Rolf and F{\"u}rst, Dieter Oswald and Klasen, Christian and Reiman, Jens and Herrmann, Harald and VanDerVen, Peter F. M.}, title = {The association of plectin with Z-discs is a prerequisite for the formation of the intermyofibrillar desmin cytoskeleton}, year = {2000}, language = {en} } @article{SchroederWarloHerrmannetal.1999, author = {Schr{\"o}der, Rolf and Warlo, Irene and Herrmann, Harald and VanDerVen, Peter F. M and Klasen, Christian and Bl{\"u}mke, Ingmar and Mundegar, Rustam R. and F{\"u}rst, Dieter Oswald and G{\"o}bel, Hans H. and Magin, Thomas}, title = {Immunogold EM reveals a close association of plectin and the desmin cytoskeleton in human skeletal muscle}, year = {1999}, language = {en} } @inproceedings{SchuhPruckerLomadzeetal.2012, author = {Schuh, Christian and Prucker, Oswald and Lomadze, Nino and Kopyshev, Alexey and Santer, Svetlana and Ruehe, Juergen}, title = {Nanogradient polymer brushes}, series = {Abstracts of papers : joint conference / The Chemical Institute of Cananda, CIC, American Chemical Society, ACS}, volume = {243}, booktitle = {Abstracts of papers : joint conference / The Chemical Institute of Cananda, CIC, American Chemical Society, ACS}, publisher = {American Chemical Society}, address = {Washington}, issn = {0065-7727}, pages = {1}, year = {2012}, language = {en} } @misc{ToetzkeKardjilovMankeetal.2017, author = {T{\"o}tzke, Christian and Kardjilov, Nikolay and Manke, Ingo and Oswald, Sascha}, title = {Capturing 3D Water Flow in Rooted Soil by Ultra-fast Neutron Tomography}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-402237}, pages = {9}, year = {2017}, abstract = {Water infiltration in soil is not only affected by the inherent heterogeneities of soil, but even more by the interaction with plant roots and their water uptake. Neutron tomography is a unique non-invasive 3D tool to visualize plant root systems together with the soil water distribution in situ. So far, acquisition times in the range of hours have been the major limitation for imaging 3D water dynamics. Implementing an alternative acquisition procedure we boosted the speed of acquisition capturing an entire tomogram within 10 s. This allows, for the first time, tracking of a water front ascending in a rooted soil column upon infiltration of deuterated water time-resolved in 3D. Image quality and resolution could be sustained to a level allowing for capturing the root system in high detail. Good signal-to-noise ratio and contrast were the key to visualize dynamic changes in water content and to localize the root uptake. We demonstrated the ability of ultra-fast tomography to quantitatively image quick changes of water content in the rhizosphere and outlined the value of such imaging data for 3D water uptake modelling. The presented method paves the way for time-resolved studies of various 3D flow and transport phenomena in porous systems}, language = {en} } @article{TrauthSchmidtViewegetal.2015, author = {Trauth, Nico and Schmidt, Christian and Vieweg, Michael and Oswald, Sascha and Fleckenstein, Jan H.}, title = {Hydraulic controls of in-stream gravel bar hyporheic exchange and reactions}, series = {Water resources research}, volume = {51}, journal = {Water resources research}, number = {4}, publisher = {American Geophysical Union}, address = {Washington}, issn = {0043-1397}, doi = {10.1002/2014WR015857}, pages = {2243 -- 2263}, year = {2015}, abstract = {Hyporheic exchange transports solutes into the subsurface where they can undergo biogeochemical transformations, affecting fluvial water quality and ecology. A three-dimensional numerical model of a natural in-stream gravel bar (20 m x 6 m) is presented. Multiple steady state streamflow is simulated with a computational fluid dynamics code that is sequentially coupled to a reactive transport groundwater model via the hydraulic head distribution at the streambed. Ambient groundwater flow is considered by scenarios of neutral, gaining, and losing conditions. The transformation of oxygen, nitrate, and dissolved organic carbon by aerobic respiration and denitrification in the hyporheic zone are modeled, as is the denitrification of groundwater-borne nitrate when mixed with stream-sourced carbon. In contrast to fully submerged structures, hyporheic exchange flux decreases with increasing stream discharge, due to decreasing hydraulic head gradients across the partially submerged structure. Hyporheic residence time distributions are skewed in the log-space with medians of up to 8 h and shift to symmetric distributions with increasing level of submergence. Solute turnover is mainly controlled by residence times and the extent of the hyporheic exchange flow, which defines the potential reaction area. Although streamflow is the primary driver of hyporheic exchange, its impact on hyporheic exchange flux, residence times, and solute turnover is small, as these quantities exponentially decrease under losing and gaining conditions. Hence, highest reaction potential exists under neutral conditions, when the capacity for denitrification in the partially submerged structure can be orders of magnitude higher than in fully submerged structures.}, language = {en} } @article{ToetzkeKardjilovMankeetal.2017, author = {T{\"o}tzke, Christian and Kardjilov, Nikolay and Manke, Ingo and Oswald, Sascha}, title = {Capturing 3D Water Flow in Rooted Soil by Ultra-fast Neutron Tomography}, series = {Scientific reports}, volume = {7}, journal = {Scientific reports}, publisher = {Macmillan Publishers Limited}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-017-06046-w}, year = {2017}, abstract = {Water infiltration in soil is not only affected by the inherent heterogeneities of soil, but even more by the interaction with plant roots and their water uptake. Neutron tomography is a unique non-invasive 3D tool to visualize plant root systems together with the soil water distribution in situ. So far, acquisition times in the range of hours have been the major limitation for imaging 3D water dynamics. Implementing an alternative acquisition procedure we boosted the speed of acquisition capturing an entire tomogram within 10 s. This allows, for the first time, tracking of a water front ascending in a rooted soil column upon infiltration of deuterated water time-resolved in 3D. Image quality and resolution could be sustained to a level allowing for capturing the root system in high detail. Good signal-to-noise ratio and contrast were the key to visualize dynamic changes in water content and to localize the root uptake. We demonstrated the ability of ultra-fast tomography to quantitatively image quick changes of water content in the rhizosphere and outlined the value of such imaging data for 3D water uptake modelling. The presented method paves the way for time-resolved studies of various 3D flow and transport phenomena in porous systems.}, language = {en} } @article{MiegelGraeffFrancketal.2017, author = {Miegel, Konrad and Gr{\"a}ff, Thomas and Franck, Christian and Salzmann, Thomas and Bronstert, Axel and Walther, Marc and Oswald, Sascha}, title = {Auswirkungen des Sturmhochwassers der Ostsee am 4./5. Januar 2017 auf das renaturierte Nieder- moor „H{\"u}telmoor und Heiligensee" an der deut- schen Ostseek{\"u}ste}, series = {Hydrologie und Wasserbewirtschaftung}, volume = {61}, journal = {Hydrologie und Wasserbewirtschaftung}, number = {4}, publisher = {Bundesanst. f{\"u}r Gew{\"a}sserkunde}, address = {Koblenz}, issn = {1439-1783}, doi = {10.5675/HyWa_2017,4_2}, pages = {232 -- 243}, year = {2017}, abstract = {Entlang der K{\"u}stenniederung des Naturschutzgebietes „H{\"u}telmoor und Heiligensee", ca. 6 km nord{\"o}stlich von Rostock-Warnem{\"u}nde gelegen, wird seit dem Jahr 2000 die K{\"u}stend{\"u}ne nicht mehr instand gehalten. Im Rahmen der Renaturierung des Gebietes werden so grunds{\"a}tzlich wieder {\"U}berflutungen bei Ostseehochwassern zugelassen, was bisher jedoch noch nicht eingetreten ist. Am 4./5. Januar 2017 ereignete sich ein Sturmhochwasser der Ostsee, mit einem Scheitelwasserstand in Warnem{\"u}nde, der sich zwischen dem 10- und 20-j{\"a}hrlichen Hochwasserstand einordnet. Dennoch kam es bei diesem Ereignis nicht zum D{\"u}nendurchbruch und zur seeseitigen {\"U}berflutung, wohl aber zum binnenseitigen Einstrom von Salz- bzw. Brackwasser. Dieser erfolgte {\"u}ber den Graben, durch den das Gebiet normalerweise {\"u}ber die Warnow in die Ostsee entw{\"a}ssert. Durch das Einstr{\"o}men {\"u}ber die Sohlschwelle, sonst Auslass des Gebietes, stiegen die Wasserst{\"a}nde und Salzkonzentrationen in der s{\"u}dwestlichen H{\"a}lfte der Niederung an. Mit zunehmender Entfernung zur Sohlschwelle waren diese Auswirkungen jedoch geringer sp{\"u}rbar. Dies gilt wegen der Retentionswirkung der Niederung mehr f{\"u}r den Wasserstand als f{\"u}r die Salzkonzentration. W{\"a}hrend der Wasserstand durch den Einstau der Niederung und {\"U}berschwemmungen fl{\"a}chenhaft anstieg, breitete sich die Salzfront pr{\"a}ferentiell in den ehemaligen Entw{\"a}sserungsgr{\"a}ben, die trotz des Einstaus nach wie vor hydraulisch aktiv sind, eher linienhaft aus. Diese Interpretation beruht auf Messergebnissen von Wasserstand, elektrischer Leitf{\"a}higkeit und Wassertemperatur.}, language = {de} } @article{HaberPohlmeierToetzkeLehmannetal.2019, author = {Haber-Pohlmeier, Sabina and T{\"o}tzke, Christian and Lehmann, E. and Kardjilov, Nikolay and Pohlmeier, A. and Oswald, Sascha}, title = {Combination of magnetic resonance imaging and neutron computed tomography for three-dimensional rhizosphere imaging}, series = {Vadose zone journal}, volume = {18}, journal = {Vadose zone journal}, number = {1}, publisher = {Soil Science Society of America}, address = {Madison}, issn = {1539-1663}, doi = {10.2136/vzj2018.09.0166}, pages = {11}, year = {2019}, abstract = {Core Ideas 3D MRI relaxation time maps reflect water mobility in root, rhizosphere, and soil. 3D NCT water content maps of the same plant complement relaxation time maps. The relaxation time T1 decreases from soil to root, whereas water content increases. Parameters together indicate modification of rhizosphere pore space by gel phase. The zone of reduced T1 corresponds to the zone remaining dry after rewetting. In situ investigations of the rhizosphere require high-resolution imaging techniques, which allow a look into the optically opaque soil compartment. We present the novel combination of magnetic resonance imaging (MRI) and neutron computed tomography (NCT) to achieve synergistic information such as water mobility in terms of three-dimensional (3D) relaxation time maps and total water content maps. Besides a stationary MRI scanner for relaxation time mapping, we used a transportable MRI system on site in the NCT facility to capture rhizosphere properties before desiccation and after subsequent rewetting. First, we addressed two questions using water-filled test capillaries between 0.1 and 5 mm: which root diameters can still be detected by both methods, and to what extent are defined interfaces blurred by these imaging techniques? Going to real root system architecture, we demonstrated the sensitivity of the transportable MRI device by co-registration with NCT and additional validation using X-ray computed tomography. Under saturated conditions, we observed for the rhizosphere in situ a zone with shorter T1 relaxation time across a distance of about 1 mm that was not caused by reduced water content, as proven by successive NCT measurements. We conclude that the effective pore size in the pore network had changed, induced by a gel phase. After rewetting, NCT images showed a dry zone persisting while the MRI intensity inside the root increased considerably, indicating water uptake from the surrounding bulk soil through the still hydrophobic rhizosphere. Overall, combining NCT and MRI allows a more detailed analysis of the rhizosphere's functioning.}, language = {en} } @article{ToetzkeKardjilovHilgeretal.2021, author = {T{\"o}tzke, Christian and Kardjilov, Nikolay and Hilger, Andr{\´e} and Rudolph-Mohr, Nicole and Manke, Ingo and Oswald, Sascha}, title = {Three-dimensional in vivo analysis of water uptake and translocation in maize roots by fast neutron tomography}, series = {Scientific Reports}, volume = {11}, journal = {Scientific Reports}, publisher = {Macmillan Publishers Limited}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-021-90062-4}, pages = {10}, year = {2021}, abstract = {Root water uptake is an essential process for terrestrial plants that strongly affects the spatiotemporal distribution of water in vegetated soil. Fast neutron tomography is a recently established non-invasive imaging technique capable to capture the 3D architecture of root systems in situ and even allows for tracking of three-dimensional water flow in soil and roots. We present an in vivo analysis of local water uptake and transport by roots of soil-grown maize plants—for the first time measured in a three-dimensional time-resolved manner. Using deuterated water as tracer in infiltration experiments, we visualized soil imbibition, local root uptake, and tracked the transport of deuterated water throughout the fibrous root system for a day and night situation. This revealed significant differences in water transport between different root types. The primary root was the preferred water transport path in the 13-days-old plants while seminal roots of comparable size and length contributed little to plant water supply. The results underline the unique potential of fast neutron tomography to provide time-resolved 3D in vivo information on the water uptake and transport dynamics of plant root systems, thus contributing to a better understanding of the complex interactions of plant, soil and water.}, language = {en} } @article{FranckeHeistermannKoehlietal.2022, author = {Francke, Till and Heistermann, Maik and K{\"o}hli, Markus and Budach, Christian and Schr{\"o}n, Martin and Oswald, Sascha}, title = {Assessing the feasibility of a directional cosmic-ray neutron sensing sensor for estimating soil moisture}, series = {Geoscientific Instrumentation, Methods and Data Systems}, volume = {11}, journal = {Geoscientific Instrumentation, Methods and Data Systems}, publisher = {Copernicus Publ.}, address = {G{\"o}ttingen}, issn = {2193-0864}, doi = {10.5194/gi-11-75-2022}, pages = {75 -- 92}, year = {2022}, abstract = {Cosmic-ray neutron sensing (CRNS) is a non-invasive tool for measuring hydrogen pools such as soil moisture, snow or vegetation. The intrinsic integration over a radial hectare-scale footprint is a clear advantage for averaging out small-scale heterogeneity, but on the other hand the data may become hard to interpret in complex terrain with patchy land use. This study presents a directional shielding approach to prevent neutrons from certain angles from being counted while counting neutrons entering the detector from other angles and explores its potential to gain a sharper horizontal view on the surrounding soil moisture distribution. Using the Monte Carlo code URANOS (Ultra Rapid Neutron-Only Simulation), we modelled the effect of additional polyethylene shields on the horizontal field of view and assessed its impact on the epithermal count rate, propagated uncertainties and aggregation time. The results demonstrate that directional CRNS measurements are strongly dominated by isotropic neutron transport, which dilutes the signal of the targeted direction especially from the far field. For typical count rates of customary CRNS stations, directional shielding of half-spaces could not lead to acceptable precision at a daily time resolution. However, the mere statistical distinction of two rates should be feasible.}, language = {en} } @misc{ToetzkeKardjilovHilgeretal.2021, author = {T{\"o}tzke, Christian and Kardjilov, Nikolay and Hilger, Andr{\´e} and Rudolph-Mohr, Nicole and Manke, Ingo and Oswald, Sascha}, title = {Three-dimensional in vivo analysis of water uptake and translocation in maize roots by fast neutron tomography}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, issn = {1866-8372}, doi = {10.25932/publishup-52991}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-529915}, pages = {12}, year = {2021}, abstract = {Root water uptake is an essential process for terrestrial plants that strongly affects the spatiotemporal distribution of water in vegetated soil. Fast neutron tomography is a recently established non-invasive imaging technique capable to capture the 3D architecture of root systems in situ and even allows for tracking of three-dimensional water flow in soil and roots. We present an in vivo analysis of local water uptake and transport by roots of soil-grown maize plants—for the first time measured in a three-dimensional time-resolved manner. Using deuterated water as tracer in infiltration experiments, we visualized soil imbibition, local root uptake, and tracked the transport of deuterated water throughout the fibrous root system for a day and night situation. This revealed significant differences in water transport between different root types. The primary root was the preferred water transport path in the 13-days-old plants while seminal roots of comparable size and length contributed little to plant water supply. The results underline the unique potential of fast neutron tomography to provide time-resolved 3D in vivo information on the water uptake and transport dynamics of plant root systems, thus contributing to a better understanding of the complex interactions of plant, soil and water.}, language = {en} } @article{HaberPohlmeierToetzkeOswaldetal.2017, author = {Haber-Pohlmeier, Sabina and T{\"o}tzke, Christian and Oswald, Sascha and Lehmann, Eberhard and Bl{\"u}mich, Bernhard and Pohlmeier, Andreas}, title = {Imaging of root zone processes using MRI T-1 mapping}, series = {Microporous and mesoporous materials : zeolites, clays, carbons and related materials}, volume = {269}, journal = {Microporous and mesoporous materials : zeolites, clays, carbons and related materials}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1387-1811}, doi = {10.1016/j.micromeso.2017.10.046}, pages = {43 -- 46}, year = {2017}, abstract = {Noninvasive imaging in the root soil compartment is mandatory for improving knowledge about root soil interactions and uptake processes which eventually control crop growth and productivity. Here we propose a method of MRI T-1 relaxation mapping to investigate water uptake patterns, and as second example, in combination with neutron tomography (NT), property changes in the rhizosphere. The first part demonstrates quantification of solute enrichment by advective transport to the roots due to water uptake. This accumulation is counterbalanced by net downward flow and dispersive spreading. One can furthermore discriminate between zones of high accumulation patterns and zones with much less enrichment. This behavior persists over days. The second part presents the novel combination of MRI with neutron tomography to couple static, proton density information of roots and their interface to the surrounding soil with information about the local water dynamics, reflected by NMR relaxation times. The root soil interface of a broad bean plant is characterized by slightly increasing MRI and NT signal intensity but decreasing T-1 relaxation time indicating locally changed soil properties.}, language = {en} } @article{ToetzkeKardjilovLenoiretal.2019, author = {T{\"o}tzke, Christian and Kardjilov, Nikolay and Lenoir, Nicolas and Manke, Ingo and Oswald, Sascha and Tengattini, Alessandro}, title = {What comes NeXT?}, series = {Optics express : the international electronic journal of optics}, volume = {27}, journal = {Optics express : the international electronic journal of optics}, number = {20}, publisher = {Optical Society of America}, address = {Washington}, issn = {1094-4087}, doi = {10.1364/OE.27.028640}, pages = {28640 -- 28648}, year = {2019}, abstract = {Here, we report on a new record in the acquisition time for fast neutron tomography. With an optimized imaging setup, it was possible to acquire single radiographic projection images with 10 ms and full tomographies with 155 projections images and a physical spatial resolution of 200 mu m within 1.5 s. This is about 6.7 times faster than the current record. We used the technique to investigate the water infiltration in the soil with a living lupine root system. The fast imaging setup will be part of the future NeXT instrument at ILL in Grenoble with a great field of possible future applications. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement}, language = {en} } @article{RudolphMohrToetzkeKardjilovetal.2017, author = {Rudolph-Mohr, Nicole and Toetzke, Christian and Kardjilov, Nikolay and Oswald, Sascha}, title = {Mapping water, oxygen, and pH dynamics in the rhizosphere of young maize roots}, series = {Journal of plant nutrition and soil science = Zeitschrift f{\"u}r Pflanzenern{\"a}hrung und Bodenkunde}, volume = {180}, journal = {Journal of plant nutrition and soil science = Zeitschrift f{\"u}r Pflanzenern{\"a}hrung und Bodenkunde}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1436-8730}, doi = {10.1002/jpln.201600120}, pages = {336 -- 346}, year = {2017}, abstract = {Rhizosphere processes are highly dynamic in time and space and strongly depend on each other. Key factors influencing pH changes in the rhizosphere are root exudation, respiration, and nutrient supply, which are influenced by soil water content levels. In this study, we measured the real-time distribution of soil water, pH changes, and oxygen distribution in the rhizosphere of young maize plants using a recently developed imaging approach. Neutron radiography was used to capture the root system and soil water distribution, while fluorescence imaging was employed to map soil pH and soil oxygen changes. Germinated seeds of maize (Zea mays L.) were planted in glass rhizotrons equipped with pH and oxygen-sensitive sensor foils. After 20 d, the rhizotrons were wetted from the bottom and time-lapsed images via fluorescence and neutron imaging were taken during the subsequent day and night cycles for 5 d. We found higher water content and stronger acidification in the first 0.5 mm from the root surface compared to the bulk soil, which could be a consequence of root exudation. While lateral roots only slightly acidified their rhizosphere, crown roots induced stronger acidification of up to 1 pH unit. We observed changing oxygen patterns at different soil moisture conditions and increasing towards lateral as well as crown roots while extending laterally with ongoing water logging. Our work indicates that plants alter the rhizosphere pH and oxygen also depending on root type, which may indirectly arise also from differences in age and water content changes. The results presented here were possible only by combining different imaging techniques to examine profiles at the root-soil interface in a comprehensive way during wetting and drying.}, language = {en} } @article{MunzOswaldSchmidt2017, author = {Munz, Matthias and Oswald, Sascha and Schmidt, Christian}, title = {Coupled Long-Term Simulation of Reach-Scale Water and Heat Fluxes Across the River-Groundwater Interface for Retrieving Hyporheic Residence Times and Temperature Dynamics}, series = {Water resources research}, volume = {53}, journal = {Water resources research}, publisher = {American Geophysical Union}, address = {Washington}, issn = {0043-1397}, doi = {10.1002/2017WR020667}, pages = {8900 -- 8924}, year = {2017}, abstract = {Flow patterns in conjunction with seasonal and diurnal temperature variations control ecological and biogeochemical conditions in hyporheic sediments. In particular, hyporheic temperatures have a great impact on many temperature-sensitive microbial processes. In this study, we used 3-D coupled water flow and heat transport simulations applying the HydroGeoSphere code in combination with high-resolution observations of hydraulic heads and temperatures to quantify reach-scale water and heat flux across the river-groundwater interface and hyporheic temperature dynamics of a lowland gravel bed river. The model was calibrated in order to constrain estimates of the most sensitive model parameters. The magnitude and variations of the simulated temperatures matched the observed ones, with an average mean absolute error of 0.7 degrees C and an average Nash Sutcliffe efficiency of 0.87. Our results indicate that nonsubmerged streambed structures such as gravel bars cause substantial thermal heterogeneity within the saturated sediment at the reach scale. Individual hyporheic flow path temperatures strongly depend on the flow path residence time, flow path depth, river, and groundwater temperature. Variations in individual hyporheic flow path temperatures were up to 7.9 degrees C, significantly higher than the daily average (2.8 degrees C), but still lower than the average seasonal hyporheic temperature difference (19.2 degrees C). The distribution between flow path temperatures and residence times follows a power law relationship with exponent of about 0.37. Based on this empirical relation, we further estimated the influence of hyporheic flow path residence time and temperature on oxygen consumption which was found to partly increase by up to 29\% in simulations.}, language = {en} } @article{ToetzkeKardjilovMankeetal.2017, author = {Toetzke, Christian and Kardjilov, Nikolay and Manke, Ingo and Oswald, Sascha}, title = {Capturing 3D Water Flow in Rooted Soil by Ultra-fast Neutron Tomography}, series = {Scientific reports}, volume = {7}, journal = {Scientific reports}, publisher = {Nature Publ. Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-017-06046-w}, pages = {9}, year = {2017}, abstract = {Water infiltration in soil is not only affected by the inherent heterogeneities of soil, but even more by the interaction with plant roots and their water uptake. Neutron tomography is a unique non-invasive 3D tool to visualize plant root systems together with the soil water distribution in situ. So far, acquisition times in the range of hours have been the major limitation for imaging 3D water dynamics. Implementing an alternative acquisition procedure we boosted the speed of acquisition capturing an entire tomogram within 10 s. This allows, for the first time, tracking of a water front ascending in a rooted soil column upon infiltration of deuterated water time-resolved in 3D. Image quality and resolution could be sustained to a level allowing for capturing the root system in high detail. Good signal-to-noise ratio and contrast were the key to visualize dynamic changes in water content and to localize the root uptake. We demonstrated the ability of ultra-fast tomography to quantitatively image quick changes of water content in the rhizosphere and outlined the value of such imaging data for 3D water uptake modelling. The presented method paves the way for time-resolved studies of various 3D flow and transport phenomena in porous systems.}, language = {en} } @article{ToetzkeOswaldHilgeretal.2021, author = {T{\"o}tzke, Christian and Oswald, Sascha and Hilger, Andr{\´e} and Kardjilov, Nikolay}, title = {Non-invasive detection and localization of microplastic particles in a sandy sediment by complementary neutron and X-ray tomography}, series = {Journal of soils and sediments : protection, risk assessment and remediation}, volume = {21}, journal = {Journal of soils and sediments : protection, risk assessment and remediation}, number = {3}, publisher = {Springer}, address = {Berlin ; Heidelberg}, issn = {1439-0108}, doi = {10.1007/s11368-021-02882-6}, pages = {1476 -- 1487}, year = {2021}, abstract = {Purpose Microplastics have become a ubiquitous pollutant in marine, terrestrial and freshwater systems that seriously affects aquatic and terrestrial ecosystems. Common methods for analysing microplastic abundance in soil or sediments are based on destructive sampling or involve destructive sample processing. Thus, substantial information about local distribution of microplastics is inevitably lost. Methods Tomographic methods have been explored in our study as they can help to overcome this limitation because they allow the analysis of the sample structure while maintaining its integrity. However, this capability has not yet been exploited for detection of environmental microplastics. We present a bimodal 3D imaging approach capable to detect microplastics in soil or sediment cores non-destructively. Results In a first pilot study, we demonstrate the unique potential of neutrons to sense and localize microplastic particles in sandy sediment. The complementary application of X-rays allows mineral grains to be discriminated from microplastic particles. Additionally, it yields detailed information on the 3D surroundings of each microplastic particle, which supports its size and shape determination. Conclusion The procedure we developed is able to identify microplastic particles with diameters of approximately 1 mm in a sandy soil. It also allows characterisation of the shape of the microplastic particles as well as the microstructure of the soil and sediment sample as depositional background information. Transferring this approach to environmental samples presents the opportunity to gain insights of the exact distribution of microplastics as well as their past deposition, deterioration and translocation processes.}, language = {en} } @article{RudolphMohrBereswillToetzkeetal.2021, author = {Rudolph-Mohr, Nicole and Bereswill, Sarah and T{\"o}tzke, Christian and Kardjilov, Nikolay and Oswald, Sascha}, title = {Neutron computed laminography yields 3D root system architecture and complements investigations of spatiotemporal rhizosphere patterns}, series = {Plant and soil}, volume = {469}, journal = {Plant and soil}, number = {1-2}, publisher = {Springer}, address = {Dordrecht}, issn = {0032-079X}, doi = {10.1007/s11104-021-05120-7}, pages = {489 -- 501}, year = {2021}, abstract = {Purpose Root growth, respiration, water uptake as well as root exudation induce biogeochemical patterns in the rhizosphere that can change dynamically over time. Our aim is to develop a method that provides complementary information on 3D root system architecture and biogeochemical gradients around the roots needed for the quantitative description of rhizosphere processes. Methods We captured for the first time the root system architecture of maize plants grown in rectangular rhizotrons in 3D using neutron computed laminography (NCL). Simultaneously, we measured pH and oxygen concentration using fluorescent optodes and the 2D soil water distribution by means of neutron radiography. We co-registered the 3D laminography data with the 2D oxygen and pH maps to analyze the sensor signal as a function of the distance between the roots and the optode. Results The 3D root system architecture was successfully segmented from the laminographic data. We found that exudation of roots in up to 2 mm distance to the pH optode induced patterns of local acidification or alkalization. Over time, oxygen gradients in the rhizosphere emerged for roots up to a distance of 7.5 mm. Conclusion Neutron computed laminography allows for a three-dimensional investigation of root systems grown in laterally extended rhizotrons as the ones designed for 2D optode imaging studies. The 3D information on root position within the rhizotrons derived by NCL explained measured 2D oxygen and pH distribution. The presented new combination of 3D and 2D imaging methods facilitates systematical investigations of a wide range of dynamic processes in the rhizosphere.}, language = {en} } @misc{FranckeHeistermannKoehlietal.2022, author = {Francke, Till and Heistermann, Maik and K{\"o}hli, Markus and Budach, Christian and Schr{\"o}n, Martin and Oswald, Sascha}, title = {Assessing the feasibility of a directional cosmic-ray neutron sensing sensor for estimating soil moisture}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, issn = {1866-8372}, doi = {10.25932/publishup-54422}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-544229}, pages = {75 -- 92}, year = {2022}, abstract = {Cosmic-ray neutron sensing (CRNS) is a non-invasive tool for measuring hydrogen pools such as soil moisture, snow or vegetation. The intrinsic integration over a radial hectare-scale footprint is a clear advantage for averaging out small-scale heterogeneity, but on the other hand the data may become hard to interpret in complex terrain with patchy land use. This study presents a directional shielding approach to prevent neutrons from certain angles from being counted while counting neutrons entering the detector from other angles and explores its potential to gain a sharper horizontal view on the surrounding soil moisture distribution. Using the Monte Carlo code URANOS (Ultra Rapid Neutron-Only Simulation), we modelled the effect of additional polyethylene shields on the horizontal field of view and assessed its impact on the epithermal count rate, propagated uncertainties and aggregation time. The results demonstrate that directional CRNS measurements are strongly dominated by isotropic neutron transport, which dilutes the signal of the targeted direction especially from the far field. For typical count rates of customary CRNS stations, directional shielding of half-spaces could not lead to acceptable precision at a daily time resolution. However, the mere statistical distinction of two rates should be feasible.}, language = {en} } @article{MunzOswaldSchmidt2016, author = {Munz, Matthias and Oswald, Sascha and Schmidt, Christian}, title = {Analysis of riverbed temperatures to determine the geometry of subsurface water flow around in-stream geomorphological structures}, series = {Journal of hydrology}, volume = {539}, journal = {Journal of hydrology}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0022-1694}, doi = {10.1016/j.jhydrol.2016.05.012}, pages = {74 -- 87}, year = {2016}, abstract = {The analytical evaluation of diurnal temperature variation in riverbed sediments provides detailed information on exchange fluxes between rivers and groundwater. The underlying assumption of the stationary, one-dimensional vertical flow field is frequently violated in natural systems where subsurface water flow often has a significant horizontal component. In this paper, we present a new methodology for identifying the geometry of the subsurface flow field using vertical temperature profiles. The statistical analyses are based on model optimisation and selection and are used to evaluate the shape of vertical amplitude ratio profiles. The method was applied to multiple profiles measured around in-stream geomorphological structures in a losing reach of a gravel bed river. The predominant subsurface flow field was systematically categorised in purely vertical and horizontal (hyporheic, parafluvial) components. The results highlight that river groundwater exchange flux at the head, crest and tail of geomorphological structures significantly deviated from the one-dimensional vertical flow, due to a significant horizontal component. The geometry of the subsurface water flow depended on the position around the geomorphological structures and on the river level. The methodology presented in this paper features great potential for characterising the spatial patterns and temporal dynamics of complex subsurface flow geometries by using measured temperature time series in vertical profiles. (C) 2016 Elsevier B.V. All rights reserved.}, language = {en} } @article{HeistermannFranckeScheiffeleetal.2023, author = {Heistermann, Maik and Francke, Till and Scheiffele, Lena and Petrova, Katya Dimitrova and Budach, Christian and Schr{\"o}n, Martin and Trost, Benjamin and Rasche, Daniel and G{\"u}ntner, Andreas and Doepper, Veronika and F{\"o}rster, Michael and K{\"o}hli, Markus and Angermann, Lisa and Antonoglou, Nikolaos and Zude, Manuela and Oswald, Sascha}, title = {Three years of soil moisture observations by a dense cosmic-ray neutron sensing cluster at an agricultural research site in north-east Germany}, series = {Earth system science data : ESSD}, volume = {15}, journal = {Earth system science data : ESSD}, number = {7}, publisher = {Copernics Publications}, address = {Katlenburg-Lindau}, issn = {1866-3508}, doi = {10.5194/essd-15-3243-2023}, pages = {3243 -- 3262}, year = {2023}, abstract = {Cosmic-ray neutron sensing (CRNS) allows for the estimation of root-zone soil water content (SWC) at the scale of several hectares. In this paper, we present the data recorded by a dense CRNS network operated from 2019 to 2022 at an agricultural research site in Marquardt, Germany - the first multi-year CRNS cluster. Consisting, at its core, of eight permanently installed CRNS sensors, the cluster was supplemented by a wealth of complementary measurements: data from seven additional temporary CRNS sensors, partly co-located with the permanent ones; 27 SWC profiles (mostly permanent); two groundwater observation wells; meteorological records; and Global Navigation Satellite System reflectometry (GNSS-R). Complementary to these continuous measurements, numerous campaign-based activities provided data by mobile CRNS roving, hyperspectral im-agery via UASs, intensive manual sampling of soil properties (SWC, bulk density, organic matter, texture, soil hydraulic properties), and observations of biomass and snow (cover, depth, and density). The unique temporal coverage of 3 years entails a broad spectrum of hydro-meteorological conditions, including exceptional drought periods and extreme rainfall but also episodes of snow coverage, as well as a dedicated irrigation experiment. Apart from serving to advance CRNS-related retrieval methods, this data set is expected to be useful for vari-ous disciplines, for example, soil and groundwater hydrology, agriculture, or remote sensing. Hence, we show exemplary features of the data set in order to highlight the potential for such subsequent studies. The data are available at doi.org/10.23728/b2share.551095325d74431881185fba1eb09c95 (Heistermann et al., 2022b).}, language = {en} } @article{BereswillGatzMillerSuetal.2023, author = {Bereswill, Sarah and Gatz-Miller, Hannah and Su, Danyang and T{\"o}tzke, Christian and Kardjilov, Nikolay and Oswald, Sascha and Mayer, Klaus Ulrich}, title = {Coupling non-invasive imaging and reactive transport modeling to investigate water and oxygen dynamics in the root zone}, series = {Vadose zone journal}, volume = {22}, journal = {Vadose zone journal}, number = {5}, publisher = {Wiley}, address = {Hoboken}, issn = {1539-1663}, doi = {10.1002/vzj2.20268}, pages = {19}, year = {2023}, abstract = {Oxygen (O-2) availability in soils is vital for plant growth and productivity. The transport and consumption of O-2 in the root zone is closely linked to soil moisture content, the spatial distribution of roots, as well as structure and heterogeneity of the surrounding soil. In this study, we measure three-dimensional root system architecture and the spatiotemporal dynamics of soil moisture (\& theta;) and O-2 concentrations in the root zone of maize (Zea mays) via non-invasive imaging, and then construct and parameterize a reactive transport model based on the experimental data. The combination of three non-invasive imaging methods allowed for a direct comparison of simulation results with observations at high spatial and temporal resolution. In three different modeling scenarios, we investigated how the results obtained for different levels of conceptual complexity in the model were able to match measured \& theta; and O-2 concentration patterns. We found that the modeling scenario that considers heterogeneous soil structure and spatial variability of hydraulic parameters (permeability, porosity, and van Genuchten \& alpha; and n), better reproduced the measured \& theta; and O-2 patterns relative to a simple model with a homogenous soil domain. The results from our combined imaging and modeling analysis reveal that experimental O-2 and water dynamics can be reproduced quantitatively in a reactive transport model, and that O-2 and water dynamics are best characterized when conditions unique to the specific system beyond the distribution of roots, such as soil structure and its effect on water saturation and macroscopic gas transport pathways, are considered.}, language = {en} }