22 Sep 2023
 | 22 Sep 2023

Hydro-pedotransfer functions: A roadmap for future development

Tobias Karl David Weber, Lutz Weihermüller, Attila Nemes, Michel Bechtold, Aurore Degré, Efstathios Diamantopoulos, Simone Fatichi, Vilim Filipović, Surya Gupta, Tobias L. Hohenbrink, Daniel R. Hirmas, Conrad Jackisch, Quirijn de Jong van Lier, John Koestel, Peter Lehmann, Toby R. Marthews, Budiman Minasny, Holger Pagel, Martine van der Ploeg, Simon Fiil Svane, Brigitta Szabó, Harry Vereecken, Anne Verhoef, Michael Young, Yijian Zeng, Yonggen Zhang, and Sara Bonetti

Abstract. Hydro-pedotransfer functions (PTFs) relate easy-to-measure and readily available soil information to soil hydraulic properties for applications in a wide range of process-based and empirical models, thereby enabling the assessment of soil hydraulic effects on hydrological, biogeochemical, and ecological processes. At least more than four decades of research have been invested to derive such relationships. However, while models, methods, data storage capacity, and computational efficiency have advanced, there are fundamental concerns related to the scope and adequacy of current PTFs, particularly when applied to parameterize models used at the field scale and beyond. Most of the PTF development process has focused on refining and advancing the regression methods, while fundamental aspects have remained largely unconsidered. Most system settings are not captured by existing PTFs, which have been built mostly for agricultural soils in temperate climates. Thus. existing PTFs largely ignorie how parent material, vegetation, land use, and climate affect processes that shape soil hydraulic properties. The PTFs used to parameterise the Richards-Richardson equation are mostly limited to predicting parameters of the van Genuchten-Mualem soil hydraulic functions, despite sufficient evidence demonstrating their shortcomings. Another fundamental issue relates to the diverging scales of derivation and application, whereby PTFs are derived based on laboratory measurements while being often applied at field to regional scales. Scaling, modulation, and constraining strategies exist to alleviate some of these shortcomings in the mismatch between scales. These aspects are addressed here in a joint effort by the members of the International Soil Modelling Consortium (ISMC) Pedotransfer Functions Working Group with the aim to systematise PTF research and provide a roadmap guiding both PTF development and use.

Tobias Karl David Weber et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2023-1860', Anonymous Referee #1, 20 Oct 2023
  • RC2: 'Comment on egusphere-2023-1860', Anonymous Referee #2, 08 Nov 2023
    • AC1: 'Reply on RC2', Tobias Karl David Weber, 08 Nov 2023

Tobias Karl David Weber et al.

Tobias Karl David Weber et al.


Total article views: 806 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
570 210 26 806 8 11
  • HTML: 570
  • PDF: 210
  • XML: 26
  • Total: 806
  • BibTeX: 8
  • EndNote: 11
Views and downloads (calculated since 22 Sep 2023)
Cumulative views and downloads (calculated since 22 Sep 2023)

Viewed (geographical distribution)

Total article views: 765 (including HTML, PDF, and XML) Thereof 765 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 10 Dec 2023
Short summary
Pedotransfer functions (PTFs) are used to predicts parameters of models describing the hydraulic properties of soils. The appropriateness of these predictions critically rely on the nature of the datasets for training the PTFs as well the physical comprehensiveness of the models. This roadmap papers is addressed at PTF developers and users, and critically reflects the utility and future of PTFs. To this end, we present a manifesto aiming at a paradigm shift in PTFs research.