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trees die standing upright

Water is crucial for trees to survive and different tree species have developed different strategies of water use. The specifics of these strategies directly affect the precipitation partitioning and the local water balance. I'm interested in this relation between hydrological processes and trees.

research topics

In the following, when I say "we," I mean my working group° at Technische Universität Braunschweig.

plant hydraulics and terrestrial ecohydrology under drought

Plant hydraulics describes the water movement through the tree. Water moves from the soil through the tree into the atmosphere due to differences in water potential. When the soil dries out, the tree struggles to get the remaining water out of the soil, because dry soil exhibits very negative water potentials that keep the water in the soil's pores. If the tree further decreases its water potential to build up a difference in water potential that would move the water into the plant, it risks damaging its own pipe system (the xylem). Therefore, many tree species prefer to close their stomata in order to avoid injury. In such a case, transpiration decreases. Damaged trees also partition the precipitation differently. We are interested in model-based studies on how these changes affect the local water budget.

Besides climate, topography and soil hydraulic properties control the available water for trees. Topography modulates lateral water fluxes both on the surface and in the subsurface. We are interested in modelling the interaction between topography, soil properties, and plant hydraulics in a coupled manner through ecohydrological models.

We are also interested in the numerical solution of the so-called Richards(on) equation that describes water flow through soil. The Richards(on) equation is notoriously challenging to solve numerically, because it contains two highly non-linear functions that describe the relation between soil moisture, soil water potential, and soil hydraulic conductivity.

Selected papers:

Selected conference contributions:

forest hydrology in a changing climate

Forest hydrology studies hydrological processes in forest-dominated ecosystems. Such systems are typically dominated by subsurface flow, because the tree roots enhance infiltration to such an extent that overland flow is usually not observed. This means that soil hydrological processes are closely linked to forest hydrology.

Forests in Europe are significantly impacted by the ongoing climate crisis. Prolonged droughts such as the one observed in the summer of 2018 have taken a toll on the overall tree vitality.

My group studies the feedback of drought stress and tree mortality into the hydrological cycle of forests using ecohydrological and plant hydraulics modelling. A key question is identifying and quantifying tree water sources. This is challenging because the root architecture of the tree is usually unkown and even if it was known, the presence of roots does not imply water uptake. It is important to know where the tree gets its water from, because it allows us to predict the available water and thus, deduce something about its resilience to droughts.

Selected conference contributions:

research tools



  1. Cáceres et al. (2023). MEDFATE 2.9.3: a trait-enabled model to simulate Mediterranean forest function and dynamics at regional scales, Geoscientific Model Development, 16:3165–3201. doi:10.5194/gmd-16-3165-2023°
  2. Cochard et al. (2021). SurEau: a mechanistic model of plant water relations under extreme drought, Annals of Forest Science, 78:55. doi:10.1007/s13595-021-01067-y°
  3. Mencuccini et al. (2019). Modelling water fluxes in plants: from tissues to biosphere, New Phytologist, 222:1207–1222. doi:10.1111/nph.15681°
  4. Nardini et al. (2018). Drought stress and the recovery from xylem embolism in woody plants, in: Cánovas, Lüttge, Matyssek (eds), Progress in Botany 79, pp. 197–232, Springer International Publishing AG, Berlin Heidelberg, Germany. doi:10.1007/124_2017_11°
  5. Peters et al. (2024). The PDI model system for parameterizing soil hydraulic properties, Vadose Zone Journal, e20338. doi:10.1002/vzj2.20338°
  6. Ruffault et al. (2022). SurEau-Ecos v2.0: a trait-based plant hydraulics model for simulations of plant water status and drought-induced mortality at the ecosystem level, Geoscientific Model Development, 15:5593–5626. doi:10.5194/gmd-15-5593-2022°
  7. Torres-Ruiz et al. (2023). Plant hydraulics at the heart of plant, crops and ecosystem functions in the face of climate change, New Phytologist, 241:948–999. doi:10.1111/nph.19463°


  1. Amatya (2016). Forest Hydrology, CAB International, Boston, MA, USA.
  2. Baird and Wilby (1999). Eco-Hydrology: Plants and water in terrestrial and aquatic environments, Routledge, London, UK.
  3. Brutsaert (2023). Hydrology: An Introduction, Cambridge University Press, Cambridge, UK.
  4. Lambers et al. (2008). Plant Physical Ecology, Springer Verlag, Berlin Heidelberg, Germany.
  5. Noble (2020). Physicochemical and Environmental Plant Physiology, Academic Press, Cambridge, MA, USA.
  6. Porporato and Yin (2022). Ecohydrology: Dynamics of Life and Water in the Critical Zone, Cambridge University Press, Cambridge, UK.
  7. van Stan II et al. (2020). Precipitation Partitioning by Vegetation, Springer-Verlag, Berlin Heidelberg, Germany.

journals i should publish in

Basic and Applied Ecology°GfÖ/Elsevier
The American Naturalist°ASN/University of Chicago Press
Consilience°self published
Digital Water°IAHR/Taylor & Francis
Ecology Letters°CNRS/Wiley
Environmental Engineering Science°Mary Ann Liebert, Inc.
Frontiers in Ecology and the Environment°ESA/Wiley
Geoscientific Model Development°EGU/Copernicus
Hydrological Processes°Wiley
Hydrology Research°DHG/WA Publishing°
Hydrology and Earth System Sciences°EGU/Copernicus
Journal of Geophysical Research: Biogeosciences°AGU/Wiley
Journal of Hydroinformatics°IAHR/IWA Publishing
New Phytologist°New Phytologist Foundation/Wiley
Peer Community Journal — Sections: Ecology / Forest & Wood Science°self published
Water Resources Research°AGU/Wiley


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Maggie Appleton°anthropologist/designer
Rek Bell°visual artist
Octavia Crompton°ecohydrologist
Chun-hong Chan°biologist turned social scientist
Khanh Dao Duc°applied mathematician
Tanguy Fardet°complex system scientist
Collin B. Edwards°mathematical ecologist
Punit Gandhi°applied mathematician
Yann Herklotz°computer scientist
Isodrones°isotope ecohydrology group, our cooler older sister
Anne Jefferson°hydrologist
Jacinta Kong°evolutionary ecologist
Robert Ladwig°limnologist, theoretical ecologist
Cynthia Li°computer scientist
David G. Litwin°hydrologist
Juliane Mai°computational hydrologist
Richard McElreath°anthropologist
Richard Nair°ecologist
Adrián Navas Montilla°numerical analyst
Eli Oat°casual blog
Jorge Peña°theoretical ecologist
Qiyao Alice Peng°applied mathematician
Timothée Poisot°computational ecologist
Maziar Raissi°applied mathematician
Alexis Simon°evolutionary biologist
Franciska de Vries°soil and ecosystem ecologist
Anna Xian°screenwriter