The use of non-conventional systems for domestic wastewater management has gained attention in rural areas of the Global South, where centralised infrastructure is often limited. This study presents the design, construction, and pilot-scale evaluation of a solar still unit operated under passive and photovoltaic-assisted active modes as a separation and polishing component for domestic wastewater from a rural site in Barrancabermeja, Colombia. Performance was assessed through physicochemical and microbiological characterisation of influent wastewater and treated condensate, together with hourly monitoring of distillate production, water temperature, glass-cover temperature, and ambient conditions. Under passive operation, a theoretical distillation model was applied, empirically adjusted, and evaluated using MAE, RMSE, MAPE, and R². Under the tested conditions, indicative within-mode reductions reached 80.9% and 89.3% for chemical oxygen demand (COD), 95.6% and 93.8% for biochemical oxygen demand (BOD₅), and 94.0% and 94.4% for total suspended solids (TSS) under passive and active modes, respectively. Microbial indicators showed minimum estimated reductions above 99.9%, with faecal coliforms reduced to very low levels in passive mode and not detected in the analysed active-mode condensate sample. Maximum daily condensate production reached 1.445 L m⁻² day⁻¹ in passive mode and 2.262 L m⁻² day⁻¹ in active mode, confirming the low-flow nature of the unit. Approximately 50% of daily production occurred between 12:00 and 15:00 h. The model reproduced the main diurnal production pattern, although empirical correction was required. Overall, the unit may improve condensate quality under pilot-scale conditions and shows potential as a polishing component within decentralised, low-flow treatment trains.

Tropical wetlands are highly sensitive to climatic and anthropogenic disturbances, and the composition of their plant communities can reflect the capacity of these ecosystems to respond to environmental perturbations. This study evaluated the relationship between aquatic macrophyte richness, community structure, and habitat vulnerability to climate change in aquatic ecosystems located in the San Luis rural district, Barrancabermeja mu-nicipality (Santander, Colombia). Macrophyte communities were characterized at 47 monitoring sites distributed across six mesohabitats: floodplain depressions, swamp la-goons, wetlands, artificial ponds (jagüeyes), naturalized ponds, and stream riparian zones. A total of 63 species belonging to 30 families and 51 genera were recorded. The re-lationships among species richness, abundance, and mesohabitat types were assessed using multivariate analyses and statistical models, including principal component anal-ysis (PCA) and generalized linear models. Results revealed clear differences in vegetation community structure among mesohabitats and dominance patterns associated with an-thropogenic disturbance. Ecosystems with higher macrophyte diversity and greater rep-resentation of native species exhibited lower levels of climatic vulnerability, whereas hab-itats dominated by eutrophication-tolerant species and subjected to greater anthropogenic pressure showed higher susceptibility. These findings highlight the ecological importance of aquatic macrophytes as indicators of environmental change and as key functional components contributing to the resilience of tropical wetlands under climate change.

Tropical wetlands are highly sensitive to climatic and anthropogenic disturbances, and their macrophyte communities provide valuable information about environmental conditions and habitat structure. This study evaluated the relationship between aquatic macrophyte richness, community composition, and habitat vulnerability to climate change in aquatic ecosystems of the San Luis rural district, Barrancabermeja municipality (Santander, Colombia). Macrophyte communities were characterized at 47 monitoring sites distributed across six mesohabitats: floodplain depressions, swamp, wetland, artificial ponds, naturalized ponds, and stream riparian zones. A total of 63 species belonging to 30 families and 51 genera were recorded. Contrary to theoretical expectations, correlation analyses showed no significant relationship between macrophyte species richness and habitat vulnerability indices (Spearman ρ = −0.118, p = 0.428; Pearson r = −0.069, p = 0.646). However, species richness differed significantly among mesohabitats (Kruskal–Wallis, p < 0.05), indicating strong spatial heterogeneity in aquatic plant distribution. In addition, multivariate analyses using Principal Component Analysis (PCA) revealed that macrophyte community composition was strongly structured by local anthropogenic activities, including livestock farming, oil palm cultivation, and wastewater inputs. Floodplain depressions and artificial ponds were dominated by disturbance-tolerant and eutrophication-resistant species such as Urochloa plantaginea and Salvinia minima, reflecting higher levels of environmental pressure. These results demonstrate that macrophyte community composition, rather than species richness alone, is a more reliable indicator of habitat conditions and anthropogenic disturbance in tropical wetland systems. Overall, this study highlights that taxonomic richness is not a robust predictor of climate-related vulnerability in highly disturbed wetlands and emphasizes the importance of considering species composition and environmental context when assessing ecosystem conditions.