Bioclimatic Indices and Inquiry-Based Learning in Higher Education: An Exploratory Mixed-Methods Study on Olive Cultivation in Mediterranean Spain

The bioclimatic optimum of wild Olea europaea var. sylvestris is broadly confined to the thermo- and mesomediterranean belts of the Mediterranean Basin, whereas cultivated olive (var. europaea) extends well beyond this envelope through varietal selection, supplementary irrigation and orchard-design adaptations. This exploratory convergent parallel mixed-methods study combines (i) a bioclimatic characterisation of six contrasting meteorological stations in southern Spain (Aracena, Arjona, Jódar, Ossa de Montiel, Tabernas, Torredonjimeno), with values reported for two reference periods (1971–2000 and the most recent World Meteorological Organization [WMO] 1991–2020 normal); and (ii) a single-group pre and post quasi-experimental intervention assessing perceived bioclimatic competence in 61 undergraduate students of Environmental Sciences. The ombrothermic index Io (annual positive precipitation/annual positive temperature × 10, a standardised indicator of water availability) ranges across the six stations from 5.88 (Aracena) to 1.14 (Tabernas); the results suggest a possible transition zone around Io ≈ 2.5 between rainfed-viable conditions and management-dependent olive cropping (irrigation, drought-tolerant varieties, soil–water conservation), although the present descriptive design does not formally demonstrate this transition. Comparison of climatic normals between the two periods indicates a consistent directional drying signal, with ΔIo negative across all six stations (sign test p = 0.031; Wilcoxon paired W = 0, p = 0.031). Self-reported student confidence rose significantly in all nine survey items (Wilcoxon signed-rank, p < 0.001 after Holm–Bonferroni correction; mean gain Δ = +1.04 on a five-point scale). Results are consistent with the hypotheses that olive cultivation outside its bioclimatic optimum may depend on agronomic compensations to remain productive, and that structured bioclimatic training can shift students’ perceived competence—acknowledging that the descriptive design does not directly demonstrate either claim, and the limitations of a single-group design and a self-report instrument.