Spatial Modelling of Soil Properties with Random Forest: Application to “Los Alcornocales” Natural Park (Andalusia, Southern Spain)

Authors

DOI:

https://doi.org/10.18172/cig.7283

Keywords:

Soil, Digital soil mapping, modelling, Random Forest , Mediterranean ecosystem

Abstract

Soil is a key component for sustaining life and maintaining ecosystem balance, as it provides nutrients and participates in essential processes such as the water cycle and carbon sequestration. Therefore, assessing its condition and promoting its conservation have become priorities in the context of climate change. One of the main challenges in soil management is its spatial representation, as the heterogeneity of soil properties and environmental variability hinder an accurate characterization of the territory. This challenge is particularly relevant because precise spatial representation enables the identification of distribution patterns, vulnerable areas, and zones of high environmental quality, thereby supporting informed decision-making. In this context, the main objective of this study is to characterize the soils of Los Alcornocales Natural Park (Andalusia, southern Spain) from a physical, organic, and hydrological perspective using advanced spatial modelling techniques. To this end, the Random Forest (RF) algorithm, based on decision trees, was employed. This algorithm allows the integration of multiple environmental variables and enhances the accuracy of the results. The modelling approach was based on the analysis of 461 soil samples (0–10 cm depth), and validation was conducted using a dual approach: external validation with 10% of the data as an independent dataset, and the internal Out-of-Bag (OOB) validation inherent to the RF algorithm. Error and accuracy metrics demonstrated the robustness of the RF model for predictive mapping in a natural park characterized by high eco-geomorphological heterogeneity (CC, R² = 0.937; Factor K, R2 0.935; COS, R² = 0.918). The results indicated that biotic factors, derived from spectral data, play a determining role in the spatial distribution of the analysed soil indicators (organic carbon, water retention capacity, and soil erodibility). This information constitutes a key tool for guiding land-use planning and sustainable management, with high potential for application in other similar Mediterranean contexts.

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Author Biographies

José Antonio Ortega-Pino, Universidad de Málaga

Instituto de Hábitat, Territorio y Digitalización. Universidad de Málaga. España

Paloma Hueso-González, Universidad de Málaga

Instituto de Hábitat, Territorio y Digitalización. Departamento de Geografía. Universidad de Málaga. España

José Damián Ruiz-Sinoga, Universidad de Málaga

Instituto de Hábitat, Territorio y Digitalización. Departamento de Geografía. Universidad de Málaga. España

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23-06-2026

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Ortega-Pino JA, Sillero-Medina JA, Hueso-González P, Ruiz-Sinoga JD. Spatial Modelling of Soil Properties with Random Forest: Application to “Los Alcornocales” Natural Park (Andalusia, Southern Spain). CIG [Internet]. 2026 Jun. 23 [cited 2026 Jul. 4];52(1):3-21. Available from: https://publicaciones.unirioja.es/ojs/index.php/cig/article/view/7283

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