Research

I graduated with my PhD from Wageningen University and Research in 2024. My thesis focused on methodological frameworks for machine learning in digital soil mapping (DSM). I have continued in this avenue of research, aiming to address statistical challenges in DSM, such as improving the statistical modelling of soil properties to enhance soil map accuracy and developing interpretive machine learning techniques using biplots.

ORCID: 0000-0001-9469-8427

Recent Publications

Richer-de-Forges, A.C., Chen, S., Heuvelink, G.B.M., van der Westhuizen, S., Orton, T.G., Bourennane, H., Arrouays, D. (2025). Does digital soil mapping prediction performance of soil texture improve when adding uncertain field texture estimates? A study based on clay content. Geoderma, 456, 117277. DOI: 10.1016/j.geoderma.2025.117277.

Tshuma, F., Bennett, J., Swanepoel, P.A., Labuschagne, J., van der Westhuizen, S., Rayns, F. (2025). Can biostimulants and tillage rotations improve dryland crop productivity and soil microbes? Agronomy Journal, 117, e21738. DOI: https://doi.org/10.1002/agj2.21738.

van der Westhuizen, S., Heuvelink, G.B.M., Gardner-Lubbe, S., Clarke, C.E. (2024). Biplots for understanding machine learning predictions in digital soil mapping. Ecological Informatics, 85, 102892. DOI: 10.1016/j.ecoinf.2024.102892.

van der Westhuizen, S., Heuvelink, G.B.M., Hofmeyr, D.P., Poggio, L., Nussbaum, M., Brungard, C. (2024). Mapping soil thickness by accounting for right-censored data with survival probabilities and machine learning. European Journal of Soil Science, 75(5), e13589. DOI: 10.1111/ejss.13589.

van der Westhuizen, S., Heuvelink, G.B.M., Hofmeyr, D.P. (2023). Multivariate random forest for digital soil mapping. Geoderma, 431. DOI: 10.1016/j.geoderma.2023.116365.

van der Westhuizen, .S., Heuvelink, G.B.M, Hofmeyr, D.P., Poggio, L. (2022). Measurement error-filtered machine learning in digital soil mapping. Spatial Statistics, DOI:10.1016/j.spasta.2021.100572.

Bodenstein, D., Clarke, C., Watson, A., Miller, J., van der Westhuizen, S., Rozanov, A. (2022). Evaluation of global and continental scale soil maps for southern Africa using selected soil properties. CATENA, DOI: 10.1016/j.catena.2022.106381.

van Beek, C.R., Guzha, T., Kopana, N., van der Westhuizen, S., Panda, S.K., Van der Vyver, C. (2021). The SINAC2 transcription factor from tomato confers tolerance to drought stress in transgenic tobacco plants. Physiology and Molecular Biology of Plants, 27(3), 907-921.

Langley, J., van der Westhuizen, S., Morland, G., van Asch, B. (2020). Mitochondrial genomes and polymorphic regions of Gonimbrasia belina and Gynanisa maja (Lepidoptera: Saturniidae), two important edible caterpillars of Southern Africa. International Journal of Biological Macromolecules, 144, 632-642.