Aarhus Universitets segl

Examining soil water vapor sorption hysteresis - exploring the influence of soil type and organic matter

Main subject area: Soil water retention in dry soil

Short project description

Hysteresis refers to the difference in water content observed between the wetting and drying branches of the soil water retention curve. Previously, it was commonly assumed that hysteresis was negligible in the dry region of this curve. However, recent experimental evidence challenges this assumption, revealing significant hysteresis in this region. This discovery underscores the importance of considering hysteresis in accurate modeling of water vapor flow, particularly in arid regions or during dry spells in summer, for precise quantification of soil evaporation and accurate estimation of soil properties based on water content measurements.

Moreover, the mechanisms responsible for this hysteresis remain unclear. We also recognize that soil properties such as texture and organic matter content may influence hysteresis. Therefore, this project aims to measure, model, and quantify sorption hysteresis for different soil types while elucidating the role of organic matter in various soil types.

Department and supervisor

Project start

Any time

Physical location of project and students work

Blichers Alle 20, Tjele, 8830-DK

Extent and type of project

45 ECTS: Experimental theses in which the student is responsible for collection and analysis of his/her own original data

60 ECTS: Experimental theses in which the student is responsible for planning, trial design and collection and analysis of his/her own original data

Additional information

The student should have basic knowledge of soil physics/soil science.

Useful Reading

  1. Arthur, E, Tuller, M, Moldrup, P, de Jonge, LW. Clay content and mineralogy, organic carbon and cation exchange capacity affect water vapour sorption hysteresis of soil. Eur J Soil Sci. 2020; 71: 204– 214. https://doi.org/10.1111/ejss.12853
  2. Lu, N., Khorshidi, M., 2015. Mechanisms for soil-water retention and hysteresis at high suction range. J Geotech Geoenviron 141(8), 04015032.