EGU2020-10434
https://doi.org/10.5194/egusphere-egu2020-10434
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Data forcing errors resulting from lack of harmonization and standardization in measurement methodologies: A comparison of soil hydrophysical data from a large EU database.

Martine van der Ploeg1 and Attila Nemes2
Martine van der Ploeg and Attila Nemes
  • 1Wageningen University, Environmental Sciences, Hydrology and Quantitative Water Management, Wageningen, Netherlands (martine.vanderploeg@wur.nl)
  • 2Norwegian Institute of Bioeconomy Research, Water Resources Norway

Soil hydro-physical properties —such as soil water retention, (un)saturated hydraulic conductivity, shrinkage and swelling, organic matter content, texture (particle distribution), structure (soil aggregation/pore structure)and bulk density— are used in many sub(surface) modeling applications. Reliable soil-hydrophysical properties are key to proper predictions with such models, yet the harmonization and standardization of these properties has not received much attention. Lack of harmonization and standardization may lead to heterogeneity in data as a result of differences in methodologies, rather than real landscape heterogeneity. A need and scope has been identified to better harmonize, innovate, and standardize methodologies regarding measuring soil hydraulic properties that form the information base of many derived products in support of EU policy. With this identified need in mind the Soil Program on Hydro-Physics via International Engagement (SOPHIE) was initiated in 2017. Besides developing new activities that may advise future measurements, we also explore historic data and metadata and mine its relevant contents. The European Hydro-pedological Data Inventory (EU-HYDI), the largest European database on measured soil hydrophysical properties, is – to date – rather under-explored in this sense, which served as motivation for this work.

From EU-HYDI we selected those records that were complete for soil texture, bulk density and organic matter, and fitted pedo-transfer functions separately for particular water retention points (at heads of 0, 2.5, 10, 100, 300, 1000, 3000, 15000 cm) and saturated hydraulic conductivity by multi-linear regression. We then subtracted the observed retention and hydraulic conductivity values from their estimated counterparts, and grouped the residuals by measurement methodologies. The results show that there can be significant differences between different methodologies and sample sizes used to obtain the water retention and hydraulic conductivity in the laboratory. The results thus show that the EU-data that may underlie large scale modelling may introduce errors in the forcing data that are attributed to a lack of harmonization and standardization in currently used measurement protocols.

How to cite: van der Ploeg, M. and Nemes, A.: Data forcing errors resulting from lack of harmonization and standardization in measurement methodologies: A comparison of soil hydrophysical data from a large EU database., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10434, https://doi.org/10.5194/egusphere-egu2020-10434, 2020