Updated European hydraulic pedotransfer functions with communicated uncertainties in the predicted variables (euptfv2)
<p>Soil hydraulic properties are often derived indirectly, i.e. computed from easily available soil properties with pedotransfer functions (PTFs), when those are needed for catchment, regional or continental scale applications. When predicted soil hydraulic parameters are used for the modellin...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2021-01-01
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| Series: | Geoscientific Model Development |
| Online Access: | https://gmd.copernicus.org/articles/14/151/2021/gmd-14-151-2021.pdf |
| Summary: | <p>Soil hydraulic properties are often derived indirectly,
i.e. computed from easily available soil properties with pedotransfer
functions (PTFs), when those are needed for catchment, regional or
continental scale applications. When predicted soil hydraulic parameters are
used for the modelling of the state and flux of water in soils, uncertainty
of the computed values can provide more detailed information when drawing
conclusions. The aim of this study was to update the previously published
European PTFs (Tóth et al., 2015, euptf v1.4.0) by providing prediction
uncertainty calculation built into the transfer functions. The new set of
algorithms was derived for point predictions of soil water content at
saturation (0 cm matric potential head), field capacity (both <span class="inline-formula">−</span>100 and <span class="inline-formula">−</span>330 cm matric potential head), wilting point (<span class="inline-formula">−</span>15 000 cm matric potential head),
plant available water, and saturated hydraulic conductivity, as well as the
Mualem–van Genuchten model parameters of the moisture retention and
hydraulic conductivity curve. The minimum set of input properties for the
prediction is soil depth and sand, silt and clay content. The effect of
including additional information like soil organic carbon content, bulk
density, calcium carbonate content, pH and cation exchange capacity were
extensively analysed. The PTFs were derived adopting the random forest
method. The advantage of the new PTFs is that they (i) provide information
about prediction uncertainty, (ii) are significantly more accurate than the
euptfv1, (iii) can be applied for more predictor variable combinations than
the euptfv1, 32 instead of 5, and (iv) are now also derived for the
prediction of water content at <span class="inline-formula">−</span>100 cm matric potential head and plant
available water content. A practical guidance on how to use the derived PTFs
is provided.</p> |
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| ISSN: | 1991-959X 1991-9603 |