Exploring medicinal plant diversity in the Serra da Estrela Natural Park (Portugal): Assessing the influence of socioeconomic variables on medicinal plant knowledge (Part II)

Medicinal plant knowledge underpins community health, yet its distribution within populations is uneven. Mountain protected areas in Europe remain understudied in this regard. To quantify intracultural variation in medicinal-plant knowledge in the Serra da Estrela Natural Park and assess associations with socio-demographic and geographic factors. Cross-sectional survey of 286 informants across five municipalities documenting 133 medicinal species. We analysed patterns using non-metric multidimensional scaling (NMDS), permutational multivariate analysis of variance (PERMANOVA), and generalised linear models (GLMs). A network approach summarised links between frequently cited plant families and disease categories. Knowledge composition and richness varied significantly among social groups. Women contributed 3507 use reports, compared to 1392 by men. PERMANOVA showed non-random differences by marital status (F = 36.55, p = 0.0001; Bonferroni pairwise p = 0.0006). GLMs identified geographic and social predictors: for digestive uses, Celorico da Beira (B = −0.302, 95 % CI −0.512 to −0.091, p = 0.005) and Guarda (B = −0.540, 95 % CI −0.755 to −0.325, p < 0.001) listed fewer species than Gouveia; for respiratory uses, several municipalities listed more species than Gouveia (e.g., Seia B = 0.769, p < 0.001). Singles reported fewer genitourinary symptoms than widows (B = −0.478, p = 0.039). Medicinal-plant knowledge in Serra da Estrela is intraculturally structured by municipality and social factors; reporting effect sizes and p-values provides decision-relevant evidence for conservation and rural-health planning. Quantifying this variability provides actionable evidence for safeguarding biocultural heritage and for integrating local knowledge into conservation and rural-health planning in rapidly changing mountain landscapes.