<p>Environmental transformation is increasingly recognized as a determinant of youth mental health, yet evidence from Indigenous and non-Indigenous communities in Latin America remains limited. This cross-sectional study examined solastalgia and its psychosocial correlates among 1,005 adolescents from three Colombian communities exposed to different territorial changes: urban construction, semi-urban agricultural transition from coffee to avocado, and extractivism in an Embera Dobidá Indigenous community. Solastalgia was assessed with the Brief Solastalgia Scale, and psychosocial variables included depressive symptoms, life satisfaction, resilience, food insecurity, adverse childhood experiences, family functioning, suicide-related indicators, and forced displacement. Because suicide risk was assessed with PANSI in non-Indigenous communities and PACES in the Indigenous community, these measures were analyzed separately. Multigroup ordinal CFA supported a common one-factor structure for solastalgia, although full scalar invariance was not established. Mean solastalgia was higher in the Indigenous community than in the urban community, with small effects. Regression models explained 54.6%–64.2% of the variance in solastalgia. Parent-child relationship was the most consistent predictor across communities, while resilience was positively associated with solastalgia in the Indigenous model. Findings suggest that adolescent solastalgia is a relational and territorial experience shaped by family, structural vulnerability, and culturally specific relationships with ancestral land and water systems</p>