PD Dr. Harald Neidhardt

Research Assistant / Wissenschaftlicher Assistent

Contact / Kontakt:
Universität Tübingen, Forschungsbereich Geographie
Rümelinstrasse 19-23, DE-72070 Tübingen, Germany
Büro: Raum W504, Westbau
Tel.: +49-(0)7071-29-77527
E-Mail: harald.neidhardt(at)uni-tuebingen.de

Sprechzeiten:  Während der vorlesungsfreien Zeit findet meine Sprechstunde noch einmal am 03.08.21 statt, danach wieder regelmäßig im Wintersemester (ab dem 15.10.2021 wöchentlich, jeden Di von 14.00-15.00 Uhr).

Teaching / Lehre

Open thesis topics / zu vergebende Abschlussarbeiten (B.Sc./M.Sc./ZuLa):

1. MSc./BSc. thesis in our ongoing reserach on P cycling in groundwater systems: details see here / bitte hier klicken  and   also here.

2. MSc./BSc. thesis related to nutrient use efficiency of plants and microorganisms in the frame of our ongoing Project in EarthShape, further details see here and upon request, please write me an Email.

3. MSc./BSc. thesis related to anthropogenic fingerprints in lake sediments in the frame of an Uni Tü collaboration project by the "Mud diggers", details upon request, please write me an Email.

Ongoing theses / laufende Abschlussarbeiten:

  1. Pollution history recorded in lake sediments - the Anlagensee in Tübingen
  2. Phosphoraufnahme von Bodenmikroorganismen in Abhängigkeit von Klima und Bodenbildung
  3. Dynamic vegetation models - ein Ableich von Modellvorhersagen mit der Realität  

Courses / Lehrveranstaltungen:

  • GEO-98: Ökosystemprozesse (winter) → Details
  • GEO-94: Forschungsseminar → Details
  • GEO-52: Exkursion Slowenien (inkl. Begleitseminar, summer) → Details
  • GEO-51: Integratives Projekt Phosphorbelastung im Grundwasser des Ammertals
  • GEO-46: Physische Geographie 3 (seminar course B, summer)
  • GEO-41: Analytische Methoden in Bodenkunde und Geoökologie (lab- and field exercises, summer)
  • GEO-23: Geographische Arbeitsmethoden I (lab- and field exercises, summer)

Completed theses / abgeschlossene Arbeiten:

  1. Der Einfluss von Offenhaltungsmaßnahmen auf den Kohlenstoffumsatz in Grünlandböden
  2. Dragonfly migration - a case study from the Baltic States
  3. Impact of climate and biota on the storage dynamics of sediment-associated organic carbon in river channels
  4. Determining the impact of bryophytes on the carbon cycle in a temperate forest ecosystem through stable isotope composition: A case study from the Schönbuch Nature Park, Germany
  5. Einfluss von Landnutzung auf die biologische Phosphorumsetzung in Böden und Gewässerbettsedimenten
  6. Nährstofflimitierung von Bodenmikroorganismen in Boden- und Streuproben entlang eines Klimagradienten in Chile
  7. Diversity effects on nutrient storage and stoichiometry of trees in a tree diversity experiment
  8. Nutrient export from river catchments by sediments along a climate gradient
  9. Microbial phosphorus cycling in vegetated buffer strips and drainage channels
  10. Forest floor contribution to the Phosphorus supply of adult beech trees (Fagus sylvatica L.) revealed by means of the oxygen isotope composition in xylem sap
  11. Eine Metaanalyse zur Verteilung von Arsen zwischen gelöster und fester Phase in Grundwasserleitersedimenten Südostasiens
  12. Distribution of halogens (Cl, Br, F, I) in soils and plants along a climate gradient of the Chilean Coastal Cordillera 
  13. Estimating fluxes of different P pools transported by suspended solids using a combination of sequential extractions and high-frequency monitoring data
  14. Characterization of P pools in floodplain sediments along a redox gradient - a case study from the Red River Delta, Vietnam
  15. Climate and litter quality controls on nutrient loss during decomposition 
  16. Der Hohenheimer Grundwasserversuch Reloaded – Pflanzenverfügbare Nährstoffe in Grünlandböden in Abhängigkeit von Bodenfeuchte und Artenzusammensetzung 
  17. Characterization of nutrient limitation to soil microbial activity along a Chilean climatic gradient
  18. Charakterisierung Phosphor-angereicherter Böden und Gewässersedimente in landwirtschaftlich geprägten Einzugsgebieten am Beispiel des Ammertals
  19. Impact of drought on plant-available nutrients in soils along a Chilean climatic gradient
  20. Charakterisierung der Phosphor Speicherung in Fließgewässersedimenten und Böden von daran angrenzenden Gewässerrandstreifen in Neckarteileinzugsgebieten im Raum Tübingen
  21. Die Reduktion der Arsenakkumulation in Nutzpflanzen durch Inokulation von Saatgut mit arbuskulären Mykorrhizapilzen. Eine Übersicht über den aktuellen Forschungsstand
  22. Simulation of soil contamination due to arsenic rich irrigation water
  23. Methoden zur Rekonstruktion der Besiedelungsgeschichte und Landschaftsgenese des Stuttgarter Talkessels. Analysen eines Bohrkerns am Standort des heutigen städtebaulichen Großprojekts Stuttgart 21
  24. Phosphate-bound oxygen isotope ratio analysis: a novel approach to characterize reducing groundwater

Personal Background / Hintergrundinformationen

Research Statement:

My current and future research as a Geoecologist aims to improve our understanding of biogeochemical key processes controlling the spatio-temporal distribution of trace elements and nutrients (e.g., arsenic, phosphorus, iron, manganese) in aquatic and terrestrial ecosystems.

In my research, I use a combination of innovative field experiments, methods and state of the art analytical techniques to obtain knowledge of the biogeochemical cycling of key elements and to identify and quantify their flows. Furthermore, I have great interest in the impact of human activities on environmental systems. An improved understanding of the processes that control the cycling of trace elements and nutrients in ecosystems is valuable for advancing the knowledge of our environment and is essential for preventing future hazards in a world increasingly affected by human activities.

Areas of Expertise:

  • Arsenic in drinking water resources and the food chain
  • Biogeochemical processes controlling the mobility of inorganic contaminants and nutrients
  • Isotope analyses as tools for investigating biogeochemical nutrient cycles
  • Enrichment and distribution of phosphorus, iron, manganese and arsenic in groundwater of SE Asia
  • Aquatic geochemistry of arsenic and phosphorus

Research Activities and cooperations / Aktuelle Forschung und Kooperationen:

  • Dynamics in Phosphorus Pools in Soils and Sediments along the Land-Freshwater Continuum of Agricultural Catchments (DFG Project)
  • Connecting the green and the grey world – an experimental approach to separating climate, vegetation and geochemical effects on nutrient cycling along a climate gradient (DFG project, PI in the second phase of the DFG-SPP program 1803 Earth Shape)
  • The cycling of halides (Cl, Br, I) in soils, plants and surface waters (involved in a DFG cooperation Project)
  • Stable oxygen isotopes in phosphate as tool for investigating phosphorus cycling in floodplain aquifers- examples from the Ammer Valley, Germany, and the Hetao Basin, PR China (two CSC - Tübingen cooperation projects)
  • The fate of anthropogenic contaminants in lake sediments
  • Analysis of glyphosate and AMPA in soil and sediment samples
  • The influence of conservation management measures on organic carbon turnover in grassland soils

Further Information:

  • Graduate of the university didactics program 'Baden-Württemberg-Zertifikat' of the HDZ Baden-Württemberg
  • Participant in the Certificate Program Leadership of the Graduate Academy of the Tübingen University
  • Member of: the International Water Aid Organisation (IWAO), the German Geological Society (DGGV), the German Soil Science Association (DBG), and the German Association of Geoecology (VGÖD)
  • Associate Editor with the Journal of Hydrology from 2018 to 2019
  • Reviews conducted for several international journals, e.g.: Applied Geochemistry, Chemosphere, Environmental Science & Technology, Geochimica et Cosmochimica Acta, Geomicrobiology Journal, Journal of Hazardous Materials, Journal of Hydrology, Science of the Total Environment, Water Research
  • Reviews conducted for the National Science Centre (NCN) Poland and the National Science Foundation (NSF) United States
  • Doctoral thesis honored with the Rudolf-Rohrbach-Prize and with a recognition award of the Dresdner Groundwater Prize

Publication Record / Publikationen


25. Li Y., Yu C., Zhao B., Chen D., Ye H., Nagel C., Shao W., Oelmann Y., Neidhardt H., Guo H.: Spatial variation in dissolved phosphorus and interactions with arsenic in response to changing redox conditions in floodplain aquifers of the Hetao Basin, Inner Mongolia. Water Research, 2022, 209, 117930. DOI: 10.1016/j.watres.2021.117930

24. Mantri S., Negri T., Sales-Ortells H., Angelov A., Peter S., Neidhardt H., Oelmann Y., Ziemert N.: Diversity of Secondary Metabolites in soil: Mining short and long read metagenome. MSystems, 2021, 6 (5), e01018-2. DOI: https://doi.org/10.1128/mSystems.01018-21 

23. Epp T., Marks M.A.W., Neidhardt H., Oelmann Y., Markl G.: Halogen (F, Cl, Br, I) contents in silt and clay fractions of a Cambisol from a temperate forest. American Mineralogist, accepted.

22. Neidhardt H., Rudischer S., Eiche E., Schneider M., Stopelli E., Duyen V.T., Trang P.T.K., Viet P.H., Neumann T., Berg M.: Phosphate immobilisation dynamics and interaction with arsenic sorption at redox transition zones in floodplain aquifers: insights from the Red River Delta, Vietnam. Journal of Hazardous Materials, 2021, 411, 125128. DOI: 10.1016/j.jhazmat.2021.125128

21. Neidhardt H.: Arbuscular mycorrhizal fungi alleviate negative effects of arsenic‐induced stress on crop plants: A meta‐analysis. Plants, People, Planet, 2020, 00:1–13,   DOI: 10.1002/ppp3.10122

20. Epp T., Neidhardt H., Pagano N., Marks M.A.W., Markl G., Oelmann Y.: Vegetation canopy effects on total and dissolved Cl, Br, F and I concentrations in soil and their fate along the hydrological flow path. Science of the Total Environment, 2020, 712, 10: 135473, DOI: 10.1016/j.scitotenv.2019.135473

19. Neidhardt H., Achten F., Kern S., Schwientek M., Oelmann Y.: Phosphorus Pool Composition in Soils and Sediments of Transitional Ecotones under the Influence of Agriculture. Special Issue “Celebrating the 350th Anniversary of Discovering Phosphorus - For Better or Worse”. Journal of Environmental Quality, 2019, 48:1325-1335, DOI: 10.2134/jeq2019.01.0012

18. Epp T., Marks M.A.W., Ludwig T., Kendrick M.A., Eby N., Neidhardt H., Oelmann Y., Markl G.:  Crystallographic and fluid compositional effects on the halogen (Cl, F, Br, I) incorporation in pyromorphite-group minerals. 2019, American Mineralogist, 104: 1673-1688, DOI: 10.2138/am-2019-7068

17. Neidhardt H., Schoeckle D., Schleinitz A., Eiche E., Berner Z. A., Trang P., Lan V., Viet P., Biswas A., Majumder A., Chatterjee D., Oelmann Y., Berg M.: Biogeochemical Phosphorus Cycling in Groundwater Ecosystems -Insights from South and Southeast Asian Floodplain and Delta Aquifers. Science of the Total Environment, 2018, 644, 1357-1370. DOI: 10.1016/j.scitotenv.2018.07.056

16. Hauenstein S., Neidhardt H., Lang F., Krüger J., Hofmann D., Pütz T., Oelmann Y.: Organic layers favor phosphorus storage and uptake by young beech trees (Fagus sylvatica L.) at nutrient poor ecosystems. Plant and Soil, 2018, 1-13. DOI: 10.1007/s11104-018-3804-5

15. Bernhard N., Moskwa L.-M., Oeser R.A., Schmidt K., Aburto F., Bader M.Y., Baumann K., Blanckenburg F.v., Boy J., Brink L.v.d., Brucker E., Canessa R., Dippold M., Ehlers T.A., Fuentes J.P., Godoy R., Köster M., Kuzyakov Y., Leinweber P., Neidhardt H., Matus F., Mueller C.W., Oelmann Y., Oses R., Osses P., Paulino L., Schaller M., Schmid M., Spielvogel S., Spohn M., Stock S., Stroncik N., Tielbörger K., Übernickel K., Scholten T., Seguel O., Wagner D. and Kühn P.: Pedogenic and microbial interrelations to regional climate and local topography: new insights from a climate gradient (arid to humid) along the Coastal Cordillera of Chile. Catena, 2018, 175, 335-355. DOI: 10.1016/j.catena.2018.06.018

14. Neidhardt H., Winkel L.H.E., Kaegi R., Stengel C., Trang P.T.K., Lan V.M., Viet P.H., Berg M.: Insights into arsenic retention dynamics of Pleistocene aquifer sediments by in situ sorption experiments. 2018, Water Research, 129, 123-132. DOI: 10.1021/acs.est.7b02097

13. Rawson J., Siade A., Sun J., Neidhardt H., Berg M., Prommer H.: Quantifying reactive transport processes governing arsenic mobility after injection of reactive organic carbon into a Bengal Bay aquifer. 2017, Environmental Science & Technology, 51 (15), 8471–8480. DOI: 10.1021/acs.est.7b02097

12. Rathi B., Neidhardt H., Berg M., Siade A., Prommer H.: Processes governing arsenic retardation on Pleistocene sediments: Adsorption experiments and model‐based analysis. 2017, Water Resources Research, 53 (5), 4344–4360. DOI: 10.1002/2017WR020551

11. Majumder S., Datta S., Nath B., Neidhardt H., Sarkar S., Roman-Ross G., Berner Z., Hidalgo M., Chatterjee D., Chatterjee D.: Monsoonal influence on variation of hydrochemistry and isotopic signatures: implications for associated arsenic release in groundwater. Journal of Hydrology, 2016, 535, 407-414. DOI: 10.1016/j.jhydrol.2016.01.052

10. Neidhardt H., Kramar U., Tang X., Guo H., Norra S.: Arsenic accumulation in the roots of Helianthus annuus and Zea mays by irrigation with arsenic-rich groundwater: insights from synchrotron X-ray fluorescence imaging. Chemie der Erde - Geochemistry, 2015, 75, 261-270. DOI: 10.1016/j.chemer.2015.04.001

9. Biswas A., Neidhardt H., Kundu A.K., Halder D., Chatterjee D., Berner Z., Jacks G., Bhattacharya P.: Spatial, vertical and temporal variation of arsenic in shallow aquifers of the Bengal Basin: Controlling geochemical processes. Chemical Geology, 2014, 387, 157-169. DOI: 10.1016/j.chemgeo.2014.08.022

8. Neidhardt H., Berner Z.A., Freikowski D., Biswas A., Majumder S., Winter J., Gallert C., Chatterjee D., Norra S.: Organic carbon induced mobilization of iron and manganese in a West Bengal aquifer and the muted response of groundwater arsenic concentrations. Chemical Geology, 2014, 367, 51-62. DOI: 10.1016/j.chemgeo.2013.12.021

7. Biswas A., Gustafsson J.P., Neidhardt H., Dipti H., Kundu A.K., Chatterjee D., Berner Z., Bhattacharya P.: Role of competing ions in the mobilization of arsenic in groundwater of Bengal Basin: Insight from surface complexation modeling. Water Research, 2014, 55, 30-39. DOI: 10.1016/j.watres.2014.02.002

6. Neidhardt H., Berg M., Stengel C., Winkel L.H.E., Kaegi R., Trang P.T.K., Lan V.T.M., Thao M.T.P., Viet P.H.: Arsenic adsorption on iron mineral phases under reducing conditions: Results from an in-situ field experiment. One Century of the Discovery of Arsenicosis in Latin America (1914-2014) As2014: Proceedings of the 5th International Congress on Arsenic in the Environment, May 11-16, 2014, Buenos Aires, Argentina, 2014 CRC Press. Link

5. Neidhardt H., Berner Z., Freikowski D., Biswas A., Winter J., Chatterjee D., Norra S.: Influences of groundwater abstraction on the distribution of dissolved As in shallow aquifers of West Bengal, India. Journal of Hazardous Materials, Special Issue: Ecotoxicology of Arsenic, 2013, 262 (15), 941–950. DOI: 10.1016/j.jhazmat.2013.01.044

4. Neidhardt H., Berner Z., Freikowski D., Biswas A., Winter J., Chatterjee D.: Reconstructing the sedimentation history of the Bengal Delta Plain by means of geochemical and stable isotopic data. Applied Geochemistry, 2013, 36, 70-82. DOI: 10.1016/j.apgeochem.2013.06.017

3. Freikowski D., Neidhardt H., Winter J., Berner Z., Gallert C.: Effect of carbon sources and of sulfate on microbial arsenic mobilization in sediments of West Bengal, India. Ecotoxicology and Environmental Safety, 2013, 91, 139-146. DOI: 10.1016/j.ecoenv.2013.01.021

2. Neidhardt H., Norra S., Tang X., Guo H., Stüben D.: Impact of irrigation with high arsenic burdened groundwater on the soil-plant system: Results from a case study in the Inner Mongolia, China. Environmental Pollution, 2012, 163, 8-13. DOI: 10.1016/j.envpol.2011.12.033

1. Biswas A., Majumder S., Neidhardt H., Halder D., Bhowmick S., Mukherjee Goswami A., Kundu A., Saha D., Berner Z., Chatterjee D.: Groundwater chemistry and redox processes: Depth dependent arsenic release mechanism. Applied Geochemistry, 2011, 26 (4), 516-525. DOI: 10.1016/j.apgeochem.2011.01.010

Other Publications:

5. Neidhardt H.: Anthropogenic disturbances of  the biogeochemical cycles of Phosphorus and Arsenic. Habilitation thesis, Department of Geosciences, Eberhard Karls University Tübingen, 2021.

4. Bernhard, N., Moskwa, L.-M., Schmidt, K., Oeser, R.A., Aburto, F., Bader, M.Y., Baumann, K., von Blanckenburg, F., Boy, J., van den Brink, L., Brucker, E., Büdel, B., Canessa, R., Dippold, M.A., Ehlers, T.A., Fuentes, J.P., Godoy, R., Jung, P., Karsten, U., Köster, M., Kuzyakov, Y., Leinweber, P., Neidhardt, H., Matus, F., Mueller, C.W., Oelmann, Y., Oses, R., Osses, P., Paulino, L., Samolov, E., Schaller, M., Schmid, M., Spielvogel, S., Spohn, M., Stock, S., Stroncik, N., Tielbörger, K., Übernickel, K., Scholten, T., Seguel, O., Wagner, D., Kühn, P., 2018. Data supplement to “Pedogenic and microbial interrelations to regional climate and local topography: New insights from a climate gradient (arid to humid) along the Coastal Cordillera of Chile”. In: GFZ Data Services, DOI: 10.5880/GFZ.5.3.2018.001

3. Majumder S., Biswas A., Neidhardt H., Sarkar S., Berner Z., Bhowmick S., Mukherjee A., Chatterjee D., Chakraborty S., Nath B., Chatterjee D.: Chapter 11: An Insight into the Spatio-vertical Heterogeneity of Dissolved Arsenic in Part of the Bengal Delta Plain Aquifer in West Bengal (India). In: Ramanathan A., Johnston S., Mukherjee A., Nath B. (Eds.): Safe and Sustainable Use of Arsenic-Contaminated Aquifers in the Gangetic Plain: A Multidisciplinary Approach. Springer, 2015, 161-177. ISBN 978-3-319-16123-5. DOI: 10.1007/978-3-319-16124-2_11

2. Neidhardt H.: Arsenic in groundwater of West Bengal: Implications from a field study. Karlsruher Mineralogische und Geochemische Hefte, Schriftenreihe des Instituts für Mineralogie und Geochemie, KIT Scientific Publishing, 2012, ISBN 978-3-86644-941-1. DOI: 10.5445/KSP/1000030868

1. Neidhardt, H.: Arsen im Grundwasser - ein Fallbeispiel aus West Bengalen, Indien. Forum der Geoökologie, 2010, 21 (3), 32-36. Link

Conference Contributions:

  • 2020: Retention of arsenic and phosphorus in aquifers along redox transition zones - an example from the Red River Delta in Vietnam. Forum on groundwater evolution and aquifer restoration (GEAR 2020), China University of Geosciences, Beijing, China.
  • 2019: Characterization of P pools in floodplain sediments along a redox gradient. AdvectAs project meeting, Tübingen, Germany.
  • 2019: Halogen (Cl, Br, F, I) contents in soils along a climate gradient in Chile. Tagung der Deutschen Bodenkundlichen Gesellschaft, Bern, Switzerland.
  • 2019: Characterization of the phosphorus pool composition in soils and sediments of transitional ecotones under the influence of agriculture. 9th International Phosphorus Workshop (IPW9), Zürich, Switzerland.
  • 2019: Der Stein der Weisen in aquatischen und semi-terrestrischen Ökosystemen. Geosymposium & Quenstedt Jahresfeier, Tübingen, Germany.
  • 2018: Investigating the Contamination of Groundwater Resources with Arsenic – A case study from Vietnam. Symposium Umweltrisiken in der Wasserforschung – Inter- und transdisziplinäre Bewertungen und Perspektiven, Karlsruhe, Germany.
  • 2018: Insights into the Biogeochemical Cycling of Phosphorus in Reducing Aquifers of South and South East Asian Floodplain and Delta Regions. EGU General Assembly 2018, Vienna, Austria.
  • 2017: Soil Contamination due to Arsenic-Enriched Irrigation Water – Impact of Irrigation Practices. Jahrestagung der Deutschen Bodenkundlichen Gesellschaft , Göttingen, Germany.
  • 2017: Connecting the green and the grey world. EarthShape participant meeting, Tübingen, Germany.
  • 2016: Phosphate-bound Oxygen Isotope Ratio Analysis: A New Tool for the Characterization of Phosphorus Cycling in Anoxic Groundwater. Presented at the 8th International Phosphorus Workshop (IPW8), Rostock, Germany.
  • 2015: As sorption behavior on iron phases at a transitioning redox front. Presentation at the 25th Goldschmidt Conference, Prague, Czech Republic.
  • 2014: Arsenic adsorption on iron mineral phases under reducing conditions: Results from an in-situ field experiment. Oral presentation at the 5th Congress on Arsenic in the Environment, Buenos Aires, Argentinia.
  • 2012: Arsenic – from groundwater into soils, plants and the food chain. Complementary case studies from West Bengal, Inner Mongolia and the Red River Delta. Oral presentation at the 4th Congress on Arsenic in the Environment, Cairns, Australia.
  • 2011: Characterization of two arsenic groundwater monitoring sites in West Bengal, India. Poster presented at the Arsenic 2011 workshop in Leipzig, Germany.
  • 2011: Characterization of the Chakdah Block, Nadia district. Oral and poster presentation at the ICDP supported IDRAs workshop in Hanoi, Vietnam.
  • 2011: Biogeochemical mobilization of arsenic from aquifer sediments in West Bengal, India. Poster presented at the VAAM annual meeting in Karlsruhe, Germany.
  • 2010: Arsenic mobilization into groundwater in West Bengal, India by sucrose injection. Oral presentation at the GEO 2010 conference in Darmstadt, Germany.
  • 2010: Temporal and spatial variations of geogenic arsenic in an aquifer in West Bengal, India. Oral presentation at the 3rd International Congress on Arsenic in the Environment in Tainan, Taiwan.
  • 2008: Neidhardt H., Norra S., Stüben D., Guo H.: Case study on arsenic enrichment in field soil and food chain in an arsenic affected area in the Inner Mongolia Autonomous Region, China. Poster presented at the Eurosoil conference in Vienna, Austria.

Curriculum vitae


venia legendi for Geochemistry, Geoecology on 21 July 2021

Since 2014:
Scientific Assistant

Geooecology Research Group of Prof. Dr. Yvonne Oelmann, Institute of Geography, Department of Geosciences, University of Tübingen

Postdoctoral Research Fellow

Group of Michael Berg, Department of Water Resources and Drinking Water, Eawag, Dübendorf, Switzerland

Research Assistant

Institute of Geography and Geoecology, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany

PhD student and Research Assistant

Institute of Mineralogy and Geochemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany

Study of Geoecology (Diploma)

University of Karlsruhe (since 2008 Karlsruhe Institute of Technology), Karlsruhe, Germany

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