EGU2020-9693
https://doi.org/10.5194/egusphere-egu2020-9693
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Evaporation from porous media as influenced by osmotic potential

Adil Salman, Deep Joshi, Mahyar Naseri, and Wolfgang Durner
Adil Salman et al.
  • TU Braunschweig, Institute of Geoecology, Germany (a.al-salman@tu-bs.de)

The measurement of the water potential is important to characterize solute transport in soil and water uptake by plants. Many researchers have characterized the matric potential and its impact on evaporation from porous media. However, only few studies have been carried out to characterize the effect of the osmotic potential. In this study, we investigated the simultaneous influences of the osmotic and matric potentials on the evaporation from soil. Our hypothesis was that both potential components affect the two stages of evaporation and that the osmotic potential in direct vicinity of the soil surface is a controlling variable. To meet our objective, we performed evaporation experiments on columns filled with pure quartz sand and natural soil materials with different textures, under climate-controlled laboratory conditions. The soils were initially saturated with different concentrations of saline solutions and evaporation from each column was measured daily. Our results show that the osmotic potential reduced the amount of evaporated water from the investigated porous media. The amount of reduction due to the osmotic potential is compared with model calculations that consider the total water potential at the soil surface.

How to cite: Salman, A., Joshi, D., Naseri, M., and Durner, W.: Evaporation from porous media as influenced by osmotic potential, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9693, https://doi.org/10.5194/egusphere-egu2020-9693, 2020

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Presentation version 1 – uploaded on 01 May 2020
  • CC1: Comment on EGU2020-9693, Dani Or, 05 May 2020

    Interesting work - thanks for sharing...

    I wonder why not representing the process via Raul's law and vapor pressure depression for salt solutions (that would affect evaporation rates) ? 

    See for example (and references there):

    Norouzi Rad, M., and Shokri, N. ( 2012), Nonlinear effects of salt concentrations on evaporation from porous mediaGeophys. Res. Lett.39, L04403, doi:.

    • AC1: Reply to CC1, Adil Salman, 05 May 2020

      Dear Dani, thank you very much for your comment. We are already taken that in our considerations, actually we are still in the beginning of series of experiments in this path. The goals is to find out a way to separate the effect of osmotic potential in soil and characterize its role in solute transportation and maybe in ET also. 
      It was very nice to have your comment, we are really appreciate that.

      Thanks again and wish you all the best.