Cambios en la composición de líquenes epífitos relacionados con la calidad del aire en la ciudad de loja (Ecuador)

Although air pollution constitutes one of the main environmental problems in the city of Loja currently, there is not an strategy for monitoring air pollution emissions. Epiphytic lichens have been widely used as bioindicators of air pollution because they get most nutrients from the air, which makes them very sensitive to changes in pollution levels. Air quality was evaluated in seven parks inside the city, where the presence and coverage of epiphytic lichens on Salix humboldtiana trees were recorded. Pollution levels were determined by the Index of Atmospheric Purity (IAP) and differences in lichen composition were assessed by a non-metric multidimensional scaling (NMDS) analysis and PERMANOVA. Our results demonstrated higher air quality in the northern and southern areas of the city, while an opposite pattern was observed in the parks from the central area of the city likely related to increased vehicular traffic. Epiphytic lichen communities were found to be excellent biological indicators of air pollution in Loja.