@article{Eliades2022, title = {Quantifying Evapotranspiration and Drainage Losses in a Semi-Arid Nectarine (Prunus persica var. nucipersica) Field with a Dynamic Crop Coefficient (Kc) Derived from Leaf Area Index Measurements}, ISSN = {2073-4441}, DOI = {10.3390/w14050734}, volume = {14}, number = {5}, year = {2022}, journal = {Water}, author = {Eliades, M. and Bruggeman, A. and Djuma, H. and Christofi, C. and Kuells, C.}, abstract = {Quantifying evapotranspiration and drainage losses is essential for improving irrigation efficiency. The FAO-56 is the most popular method for computing crop evapotranspiration. There is, however, a need for locally derived crop coefficients (Kc) with a high temporal resolution to reduce errors in the water balance. The aim of this paper is to introduce a dynamic Kc approach, based on Leaf Area Index (LAI) observations, for improving water balance computations. Soil moisture and meteorological data were collected in a terraced nectarine (Prunus persica var. nucipersica) orchard in Cyprus, from 22 March 2019 to 18 November 2021. The Kc was derived as a function of the canopy cover fraction ©, from biweekly in situ LAI measurements. The use of a dynamic Kc resulted in Kc estimates with a bias of 17 mm and a mean absolute error of 0.8 mm. Evapotranspiration (ET) ranged from 41% of the rainfall (P) and irrigation (I) in the wet year (2019) to 57% of P + I in the dry year (2021). Drainage losses from irrigation (DR_I) were 44% of the total irrigation. The irrigation efficiency in the nectarine field could be improved by reducing irrigation amounts and increasing the irrigation frequency. Future studies should focus on improving the dynamic Kc approach by linking LAI field observations with remote sensing observations and by adding ground cover observations.} }

@article{KISI2024102017, title = {Enhancing river flow predictions: Comparative analysis of machine learning approaches in modeling stage-discharge relationship}, journal = {Results in Engineering}, volume = {22}, pages = {102017}, year = {2024}, issn = {2590-1230}, doi = {https://doi.org/10.1016/j.rineng.2024.102017}, url = {https://www.sciencedirect.com/science/article/pii/S2590123024002706}, author = {Ozgur Kisi and Hazi {Mohammad Azamathulla} and Fatih Cevat and Christoph Külls and Mehdi Kuhdaragh and Mehdi Fuladipanah}, keywords = {Stage, Discharge, Artificial neural networks, Neuro-fuzzy, Rating curve, Estimation}, abstract = {Streamflow, a pivotal variable in water resources management, holds profound significance in shaping the decision-making processes of hydrologic projects. This paper tries to delve into the exploration of the stage-discharge relationship using three machine learning methods (MLMs) namely multi-layer neural networks (MLNN), radial basis neural networks (RBNN), and neuro-fuzzy systems (ANFIS) to predict and simulate mean daily stage-discharge data derived from two monitoring stations, Bulakbasi and Karaozü, Kizilirmak River, Turkey. Root mean square error (RMSE), Mean absolute percentage error (MAPE), coefficient of determination (R2), and the Developed Discrepancy Ratio (DDR) metrics were utilized to MLMs' performance assessment. The performance evaluation indices (RMSE, MAEP, R2, DDR) for the preeminent MLNN model applied to Bulakhbashi and Karasu stations were determined as (0.29, 1.57, 0.9998, 17.62) and (1.71, 6.56, 0.9980, 6.65), respectively. The MLNN model contributed to a notable enhancement in the RMSE performance index for the aforementioned stations, exhibiting improvements of 87% and 56%, respectively. These results affirm the MLNN's proficiency in accurately capturing the stage-discharge at both monitoring stations.} }

@article{OLA2024101405, title = {Remediating Oil Contamination in the Niger Delta Region of Nigeria: Technical Options and Monitoring Strategies}, journal = {The Extractive Industries and Society}, volume = {17}, pages = {101405}, year = {2024}, issn = {2214-790X}, doi = {https://doi.org/10.1016/j.exis.2024.101405}, url = {https://www.sciencedirect.com/science/article/pii/S2214790X24000030}, author = {Ibukun Ola and Carsten Drebenstedt and Robert M. Burgess and Martin Mensah and Nils Hoth and Christoph Külls}, keywords = {Nigeria, Niger Delta, Ogoni, Oil remediation, Organoclay capping, Permeable reactive barriers, bioremediation}, abstract = {The Niger Delta, a region of immense ecological significance and rich biodiversity, has long faced the severe consequences of petroleum contamination resulting from intense oil exploration and various environmental stressors. In response to the pressing need for effective remediation and monitoring of contaminated matrices in the Niger Delta, this study delves into a comprehensive analysis. Through a systematic assessment considering certain criteria, advanced remediation technologies tailored to the specific environmental challenges in the region are identified. Organoclay-based reactive core materials (RCM), permeable reactive barriers (PRBs), and bioremediation have emerged as highly suitable solutions for remediating sediment, groundwater, and soil, respectively. These technologies span the spectrum from non-intrusive to less intrusive methods and have demonstrated exceptional efficacy in mitigating hydrocarbon contamination under the delta's prevailing complex conditions. In addressing the critical need for monitoring the progress of remediation and post-remediation stages, a fully integrated approach is proposed. This strategy combines three essential components for tracking environmental quality improvements and understanding the recovery processes: traditional total chemical concentration (Ctotal) estimates, passive sampler-derived freely dissolved chemical concentration (Cfree) measurements, and ecological monitoring, specifically the recolonization test. Together, these components provide a more accurate description of risk and a comprehensive understanding of the recovery process. This study is concentrated on the systematic selection, supported by credible case study information, of tailored technical solutions for addressing the unique challenges of the Niger Delta. The novel outcomes lie in the identification of technology solutions carefully adapted for the region, representing a significant advancement in the field of environmental remediation in the Niger Delta. Science-based remediation and monitoring are key, and this study offers a decision support tool for selecting optimal methods in the ongoing cleanup of the Niger Delta and similar areas. This supports a healthier, more resilient environment for both the region's inhabitants and ecosystems.} }

@article{mahindawansha2020investigating, title={Investigating unproductive water losses from irrigated agricultural crops in the humid tropics through analyses of stable isotopes of water}, author={Mahindawansha, Amani and K\“ulls, Christoph and Kraft, Philipp and Breuer, Lutz}, journal={Hydrology and Earth System Sciences}, volume={24}, number={7}, pages={3627–3642}, year={2020}, publisher={Copernicus GmbH} }

@article{christofi2020hydrochemical, title={Hydrochemical evolution of groundwater in gabbro of the Troodos Fractured Aquifer. A comprehensive approach}, author={Christofi, Christos and Bruggeman, Adriana and Kuells, Christoph and Constantinou, Costas}, journal={Applied Geochemistry}, volume={114}, pages={104524}, year={2020}, publisher={Pergamon} }

@article{jin2020fdm, title={FDM based OA-ICOS for high accuracy 13C quantification in gaseous CO2}, author={Jin, Zehao and K\”ulls, Christoph}, journal={E\&ES}, volume={446}, number={3}, pages={032061}, year={2020} }

@inproceedings{doulgeris2020prediction, title={Prediction of seawater intrusion to coastal aquifers based on non-dimensional diagrams}, author={Doulgeris, Charalampos and Tziritis, Evangelos and Pisinaras, Vassilios and Panagopoulos, Andreas and K\“ulls, Christoph}, booktitle={EGU General Assembly Conference Abstracts}, pages={4073}, year={2020} }

@inproceedings{tziritis2020medsal, title={MEDSAL Project-Salinization of critical groundwater reserves in coastal Mediterranean areas: Identification, risk assessment and sustainable management with the use of integrated modelling and smart ICT tools}, author={Tziritis, Evangelos and Aschonitis, Vassilis and Balacco, Gabriella and Daras, Petros and Doulgeris, Charalampos and Fidelibus, Maria Dolores and Gaubi, Elyes and Gueddari, Moncef and G\”uler, C\“uneyt and Hamzaoui, Fadoua and others}, booktitle={EGU General Assembly Conference Abstracts}, pages={2326}, year={2020} }

@inproceedings{kruger2020groundwater, title={Groundwater recharge estimates with soil isotope profiles-is there a bias on coarse-grained hillslopes?}, author={Kr\”uger, Nina and K\“ulls, Christoph and Bruggeman, Adriana and Eliades, Marinos and Christophi, Christos and Rigas, Michali and Eracleous, Theodosia}, booktitle={EGU General Assembly Conference Abstracts}, pages={9840}, year={2020} }

@article{jobin2019application, title={Application of a laser-based spectrometer for continuous in situ measurements of stable isotopes of soil CO 2 in calcareous and acidic soils}, author={Jobin, Joseph and K\”ulls, Christoph and Arend, Matthias and Schaub, Marcus and Hagedorn, Frank and Gessler, Arthur and Weiler, Markus}, journal={Soil}, volume={5}, number={1}, pages={49–62}, year={2019}, publisher={Copernicus GmbH} }

@article{ardelt2018towards, title={Towards intrinsic molecular communication using isotopic isomerism}, author={Ardelt, Gunther and K\“ulls, Christoph and Hellbr\”uck, Horst}, journal={Open Journal of Internet Of Things (OJIOT)}, volume={4}, number={1}, pages={135–143}, year={2018}, publisher={RonPub} }

@article{androvitsanea2018hydrologische, title={Hydrologische Bedingungen im Heraion von Samos vom 12. bis 8. Jh. v. Chr. und ihre Bedeutung f\“ur die wasserbauliche Infrastruktur}, author={Androvitsanea, Anna and Fawzy, Mohammad and Fuchs, Johanna and Kuells, Christoph Jan and Fahlbusch, Henning and Heiden, Joachim}, journal={Environmental Water Engineering}, volume={1}, number={1}, pages={1–21}, year={2018} }

@article{hamutoko2014fingerprinting, title={A fingerprinting method for the identification of uranium sources in alluvial aquifers: An example from the Khan and Swakop Rivers, Namibia}, author={Hamutoko, JT and Mapani, BS and Ellmies, R and Bittner, A and Kuells, C}, journal={Physics and Chemistry of the Earth, Parts A/B/C}, volume={72}, pages={34–42}, year={2014}, publisher={Pergamon} }

@Article{Baram_etal2013, author=“Baram, S. and Ronen, Z. and Kurtzman, D. and K\”ulls, C. and Dahan, O.”, title=“Desiccation-crack-induced salinization in deep clay sediment”, journal=“Hydrology and Earth System Sciences”, year=“2013”, publisher=“Copernicus GmbH”, volume=“17”, number=“4”, pages=“1533–1545”, optnote=“exported from refbase (http://uhydro.de/base/show.php?record=1230), last updated on Fri, 10 Apr 2015 12:35:54 +0200” }

@Article{Davila_etal2013, author=“Davila, P.F. and K\”ulls, C. and Weiler, M.“, title=“A toolkit for groundwater mean residence time interpretation with gaseous tracers”, journal=“Computers \& Geosciences”, year=“2013”, publisher=“Pergamon”, volume=“61”, pages=“116–125”, optnote=“exported from refbase (http://uhydro.de/base/show.php?record=1232), last updated on Fri, 10 Apr 2015 12:36:49 +0200” }

@Article{Frey_etal2011, author=“Frey, S. and K”u\lls, C. and Schlosser, C.”, title=“New Hydrological Age-Dating Techniques using Cosmogenic Radionuclides Beryllium-7 and Sodium-22”, year=“2011”, optnote=“exported from refbase (http://uhydro.de/base/show.php?record=1233), last updated on Fri, 10 Apr 2015 12:35:09 +0200” }

@InProceedings{Gaj_etal2014, author=“Gaj, M. and Beyer, M. and Hamutoko, J. and Uugulu, S. and Wanke, H. and Koeniger, P. and K\”ulls, C. and Lohe, C. and Himmelsbach, T.“, title=“How do soil types affect stable isotope ratios of 2H and 18O under evaporation: A Fingerprint of the Niipele subbasin of the Cuvelai-Etosha basin, Namibia”, booktitle=“EGU General Assembly Conference Abstracts”, year=“2014”, volume=“16”, pages=“5890”, optnote=“exported from refbase (http://uhydro.de/base/show.php?record=1236), last updated on Fri, 10 Apr 2015 12:35:09 +0200” }

@Article{Garvelmann_etal2012, author=“Garvelmann, J. and K\”ulls, C. and Weiler, M.”, title=“A porewater-based stable isotope approach for the investigation of subsurface hydrological processes”, journal=“Hydrology and Earth System Sciences”, year=“2012”, publisher=“Copernicus GmbH”, volume=“16”, number=“2”, pages=“631–640”, optnote=“exported from refbase (http://uhydro.de/base/show.php?record=1216), last updated on Fri, 10 Apr 2015 12:37:18 +0200” }

@Article{Garvelmann_etal2011, author=“Garvelmann, J. and K\”ulls, C. and Weiler, M.“, title=“A porewater – based stable isotope approach for the investigation of subsurface hydrological processes (discussion paper)”, journal=“Hydrology and Earth System Sciences Discussions”, year=“2011”, volume=“8”, number=“5”, pages=“9089–9112”, optnote=“exported from refbase (http://uhydro.de/base/show.php?record=955), last updated on Wed, 29 Aug 2012 18:58:15 +0200”, issn=“1812-2116”, doi=“10.5194/hessd-8-9089-2011” }

@Article{Klaus_etal2013, author=“Klaus, J. and Zehe, E. and Elsner, M. and K\”ulls, C. and McDonnell, J.J.”, title=“Macropore flow of old water revisited: experimental insights from a tile-drained hillslope”, journal=“Hydrology and Earth System Sciences”, year=“2013”, publisher=“Copernicus GmbH”, volume=“17”, number=“1”, pages=“103–118”, optnote=“exported from refbase (http://uhydro.de/base/show.php?record=1228), last updated on Fri, 10 Apr 2015 12:39:05 +0200” }

@Article{Klaus_etal2012, author=“Klaus, J. and Zehe, E. and Elsner, M. and K\”ulls, C. and McDonnell, J.J.“, title=“Macropore flow of old water revisited: where does the mixing occur at the hillslope scale?”, journal=“Hydrology and Earth System Sciences Discussions”, year=“2012”, publisher=“Copernicus GmbH”, volume=“9”, number=“4”, pages=“4333–4380”, optnote=“exported from refbase (http://uhydro.de/base/show.php?record=1205), last updated on Fri, 10 Apr 2015 12:39:17 +0200” }

@Article{Kuells2012, author=“K\”ulls, C.”, title=“Rekonstruktion hydrologischer Extreme in der Namibw{\”u}ste“, year=“2012”, address=“Freiburg”, volume=“101”, pages=“69–82”, optkeywords=“Namib”, optkeywords=“Grundwasser”, optkeywords=“Isotope”, optkeywords=“Altersdatierung”, optnote=“exported from refbase (http://uhydro.de/base/show.php?record=952), last updated on Mon, 13 Feb 2012 20:17:34 +0100”, language=“dt.” }

@InProceedings{Kuells_etal2014, author=“K\”ulls, C. and Nunes, A. and K\”olbel-Batista, M. and Branquinho, C. and Bianconi, N. and Costantini, E.“, title=“Integrated use of soil physical and water isotope methods for ecohydrological characterization of desertified areas”, booktitle=“EGU General Assembly Conference Abstracts”, year=“2014”, volume=“16”, pages=“15430”, optnote=“exported from refbase (http://uhydro.de/base/show.php?record=1235), last updated on Fri, 10 Apr 2015 12:38:28 +0200” }

@Article{Mueller_etal2014, author=“Mueller, M.H. and Alaoui, A. and K\”ulls, C. and Leistert, H. and Meusburger, K. and Stumpp, C. and Weiler, M. and Alewell, C.”, title=“Tracking water pathways in steep hillslopes by $\delta$ 18 O depth profiles of soil water”, journal=“Journal of Hydrology”, year=“2014”, publisher=“Elsevier”, volume=“519”, pages=“340–352”, optnote=“exported from refbase (http://uhydro.de/base/show.php?record=1234), last updated on Fri, 10 Apr 2015 12:35:09 +0200” }

@incollection{Adar.46, author = {Adar, E. and K\“ulls, C.}, title = {MCMsf - Mixing-cell model for a steady flow MIG: Mixing-cell input generator. A short manual for installation and operation of MCMsf using the MIG mixing-cell input generator}, URL = {http://www-naweb.iaea.org/napc/ih/documents/TECDOCS/TECDOC{\%}20Flow{\%}20and{\%}20transport{\%}20in{\%}20groundwater{\%}202002{\%}20UIAGS.PDF}, series = {IAEA-TECDOC}, number = {1448}, year = {2002}, publisher = {IAEA}, address = {Vienna}, booktitle = use_of_isotopes_for_analyses_of_flow_and_transport_dynamics_in_groundwater_systems, pages = {1–29}, keywords = {groundwater,mixing,modeling} }

@article{Benito.51, author = {Benito, G. and Rohde, R. and Seely, M. and K\”ulls, C. and Dahan, O. and Enzel, Y.}, title = {Management of Alluvial Aquifers in Two Southern African Ephemeral Rivers: Implications for IWRM}, URL = {http://www.springerlink.com/index/A444075625259522.pdf}, ISSN = {0920-4741 (Print) 1573-1650 (Online)}, DOI = {10.1007/s11269-009-9463-9}, volume = {24}, number = {4}, year = {2010}, journal = {Water Resources Management}, pages = {641–667} } @article{Dahan.59, author = {Dahan, O. and Shani, Y. and Enzel, Y. and Yechieli, Y. and Yakirevich, A.}, title = {Direct measurements of floodwater infiltration into shallow alluvial aquifers}, volume = {344}, year = {2007}, journal = {Journal of Hydrology}, pages = {157–170} }

@article{Dahan.11, author = {Dahan, O. and Tatarsky, B. and Enzel, Y. and K\“ulls, C. and Seely, M. and Benito, G.}, title = {Dynamics of flood water infiltration and ground water recharge in hyperarid desert}, URL = {http://www3.interscience.wiley.com/journal/119390554/abstract}, DOI = {10.1111/j.1745-6584.2007.00414.x}, volume = {46}, number = {3}, year = {2008}, journal = {Ground Water}, pages = {450–461} }

@incollection{Demuth.15, author = {Demuth, S. and K\”ulls, C.}, editor = {Rosberg, D. and al.}, title = {Probability analysis and regional aspects of droughts in southern Germany}, series = {Red Book Series}, volume = {240}, year = {1997}, publisher = {IAHS Red Book Series}, address = {Wallingford U.K.}, booktitle = {Sustainability of Water Resources under Increasing Uncertainty}, pages = {97–114} }

@book{Gaiser.52, author = {Gaiser, T. and Krol, M. and Frischkorn, H. and Araujo, J. C.}, title = {Global Change and Regional Impacts}, edition = {1}, year = {2003}, publisher = {Springer}, address = {Berlin, Heidelberg, New York}, keywords = {Brazil,IWRM} }

@article{Heidbuechl.50, author = {Heidbuechl, I. and K\“ulls, C.}, title = {Groundwater controls on flash flood shape and incidence}, URL = {http://www.cosis.net/abstracts/EGU2008/11123/EGU2008-A-11123-2.pdf?PHPSESSID=d1b7d1803114b6424729e5e35ffc4f7f}, year = {2008}, journal = {Geophysical Research Abstracts} }

@article{Kulls.13, author = {K\”ulls, C. and Leibundgut, C. and Schwarz, U. and Schick, A.}, title = {Channel infiltration study using dye tracers}, URL = {http://iahs.info/redbooks/a232/iahs{\_}232{\_}0429.pdf}, ISSN = {0-947571-64-7}, number = {232}, year = {1994}, journal = IAHS, pages = {429–436}, month = {August} }

@mastersthesis{Kulls.19, author = {K\“ulls, C.}, title = {Transmission Losses from Ephemeral Floods in Nahal Zin, Israel}, year = {1994}, school = {M. Sc. Thesis, Institute of Hydrology}, address = {Albert Ludwigs University Freiburg} }

@article{Kulls.12, author = {K\”ulls, C. and Adar, E. and Udluft, P.}, title = {Resolving patterns of groundwater flow by inverse hydrochemical modelling in a semiarid Kalahari basin}, URL = {http://iahs.info/redbooks/a262/26265.htm}, number = {262}, year = {2000}, journal = {IAHS}, pages = {447–451} }

@misc{Kulls.53, author = {K\“ulls, C. and Salameh, E. and Udluft, P.}, title = {Assessing water supplies for irrigation - availability of natural resources and sustainability indices}, URL = {http://ftp.gwdg.de/pub/tropentag/proceedings/2000/Full{\%}20Papers/Section{\%}20II/WG{\%}20d/Kuells{\%}20C.pdf}, organization = {Univ. Hohenheim}, year = {2000}, location = {Hohenheim} }

@phdthesis{Kulls.14, author = {K\”ulls, C.}, title = {Groundwater of the North-Western Kalahari, Namibia: Estimation of recharge and quantification of the flow systems}, year = {2000}, school = {Maximilians University}, address = {W\“urzburg}, journal = {Doktorarbeit, Universit\”at W\“urzburg} }

@incollection{Kulls.23, author = {K\”ulls, C. and Udluft, P.}, title = {Mapping the availability and dynamics of groundwater recharge. Part II: Case studies}, year = {2000}, booktitle = {3rd Congress on Regional Geological Cartography and Information Systems}, pages = {163–168} }

@article{Kulls.30, author = {K\“ulls, C.}, title = {Groundwater of the North-Western Kalahari, Namibia. Estimation of Recharge and Quantification of the Flow Systems}, URL = {http://nbn-resolving.de/urn:nbn:de:bvb:20-1180680}, ISSN = {09309-3757}, volume = {28}, year = {2001}, journal = {Hydrogeologie und Umwelt}, pages = {1–165} }

@article{Kulls.38, author = {K\”ulls, C.}, title = {Indicators for the the distribution of flood recharge along ephemeral rivers}, year = {2006}, journal = {Geophysical Research Abstracts} }

@article{Kulls.36, author = {K\“ulls, C.}, title = {Large basins as isotopic monitors of hydrologic response in arid zones}, year = {2007}, journal = {Geophysical Research Abstracts} }

@article{Kulls.49, author = {K\”ulls, C.}, title = {Interaction between riparian phreatophytes, alluvial aquifers and channel processes}, year = {2007}, journal = {Geophysical Research Abstracts} }

@misc{Kulls.44, author = {K\“ulls, C.}, title = {The WADE experience-twinning hydrological research and IWRM in European and Southern African drylands}, year = {2008} }

@misc{Kulls.45, author = {K\”ulls, C.}, title = {Significant trends, underlying processes and indicators-the validation of hydrological change}, year = {2008}, }

@article{Kulls.43, author = {K\“ulls, C. and Zabori, J.}, title = {On the representation of hydrological processes in current SVAT schemes-comparison and perspective (Invited)}, URL = {http://adsabs.harvard.edu/abs/2009AGUFM.B14A..01K}, year = {2009}, journal = {AGU Fall Meeting Abstracts} }

@article{Klaus.20, author = {Klaus, J. and K\”ulls, C. and Dahan, O.}, title = {Evaluating the recharge mechanism of the Lower Kuiseb Dune area using mixing cell modeling and residence time data}, URL = {http://linkinghub.elsevier.com/retrieve/pii/S002216940800293X}, DOI = {10.1016/j.jhydrol.2008.06.012}, volume = {358}, number = {3-4}, year = {2008}, journal = {J. Hydrol.}, pages = {304–316} }

@article{Klock.37, author = {Klock, H. and K\“ulls, C. and Udluft, P.}, title = {Estimation of relative recharge values for the northern Kalahari catchment, Namibia}, URL = {http://www.csa.com/partners/viewrecord.php?requester=gs\textbackslash{\&}collection=ENV\textbackslash{\&}recid=4873320}, volume = {22}, number = {4}, year = {2000}, journal = {Journal of African Earth Sciences}, pages = {47} }

@incollection{Klock.34, author = {Klock, H. and K\”ulls, C. and Udluft, P.}, title = {Estimating recharge values using hydrochemical and geological data: A case study from the semiarid Kalahari}, URL = {http://cat.inist.fr/?aModele=afficheN{\&}cpsidt=1021076}, ISBN = {1-901502-56-2}, series = {Red Book Series}, number = {269}, volume = {269}, year = {2001}, publisher = {IAHS Red Book Series}, address = {Wallingford U.K.}, booktitle = {Impact of human activity on groundwater dynamics}, pages = {25–31} }

@book{Leibundgut.29, author = {Leibundgut, C. and Maloszewski, P. and K\“ulls, C.}, title = {Tracers in hydrology}, URL = {http://eu.wiley.com/WileyCDA/WileyTitle/productCd-0470518855.html}, ISBN = {978-0470518854}, edition = {1st}, year = {2009}, publisher = {John Wiley \& Sons} }

@article{Morin.18, author = {Morin, E. and Grodek, T. and Enzel, Y. and Dahan, O. and Benito, G. and K\”ulls, C. and Jacoby, Y. and van Langenhove, G. and Seely, M.}, title = {Flood routing and alluvial aquifer recharge along the ephemeral arid Kuiseb River, Namibia}, URL = {http://linkinghub.elsevier.com/retrieve/pii/S0022169409000882}, volume = {368}, year = {2009}, journal = {J. Hydrol.}, pages = {262–275} }

@inproceedings{Troger.54, author = {Tr\“oger, U. and Dias, C. L. and Guillaumon, J. R. and Iritani, M. A. and K\”ulls, C. and Schuler, G.}, title = {Remarks and new data about the recharge of the Guarani Aquifer System}, publisher = {IAH}, URL = {http://www.igeograf.unam.mx/aih/pdf/T5/T5-39.pdf}, series = {IAH Conf. Proceedings}, year = {2004}, publisher = {IAH}, address = {Mexico City}, booktitle = XXXIIICongressAIH, pages = {T5-39} }

@incollection{Udluft.16, author = {Udluft, P. and K\“ulls, C.}, title = {Mapping the availability and dynamics of groundwater recharge: Part I: Modelling techniques}, booktitle = {3rd Congress on Regional Geological Cartography and Information Systems}, pages = {337–340}, year = {2000} }

@incollection{Voerkelius.22, author = {Voerkelius, S. and K\”ulls, C. and Santiago, M. and Frischkorn, H. and Alves dos Santos Semrau, L. and Heinrichs, G. and Lopez Gil, M. M.}, title = {Investigations on Water Management and Water Quality in Picos/PI and Taua/CE}, ISBN = {3540438246}, year = {2003}, publisher = {Springer}, address = {Berlin, Heidelberg, New York}, booktitle = {Investigations on Water Management and Water Quality in Picos/PI and Taua/CE}, pages = {173–184} }

@article{Zagana.39, author = {Zagana, E. and K\“ulls, C. and Udluft, P.}, title = {Hydrochemie und Wasserhaushalt des Aliakmonas}, URL = {http://cat.inist.fr/?aModele=afficheN{\&}cpsidt=1328751}, ISSN = {0083-6915}, volume = {94}, year = {2000}, journal = {Vom Wasser}, pages = {29–39} }

@article{Zagana.17, author = {Zagana, E. and Obeidat, M. and K\”ulls, C. and Udluft, P.}, title = {Chloride, hydrochemical and isotope methods of groundwater recharge estimation in eastern Mediterranean areas: a case study in Jordan}, URL = {http://www3.interscience.wiley.com/journal/114202153/abstract}, DOI = {10.1002/hyp.6390}, volume = {21}, number = {16}, year = {2007}, journal = {Hydrol. Proc.}, pages = {2112–2123} }

@article{Zagana.21, author = {Zagana, E. and K\“ulls, C. and Udluft, P. and Constantinou, C.}, title = {Methods of groundwater recharge estimation in Eastern Mediterranean - a water balance model application in Greece, Cyprus and Jordan}, URL = {http://www3.interscience.wiley.com/journal/114202156/abstract}, ISSN = {1099-1085}, DOI = {10.1002/hyp.6392}, volume = {21}, number = {18}, year = {2007}, journal = {Hydrol. Proc.}, pages = {2405–2414} }