Bases to evaluate air quality in Uruguay department, province of Entre Ríos: changes in diversity and coverage of lichens between urban and native forest ecosystems.

Abstract

Air pollution, caused mainly by emissions from anthropogenic activities, represents a significant environmental risk to health. According to the World Health Organization, in 2019, 99% of the world’s population lived in places where air quality guidelines were not respected. However, monitoring air quality to ensure compliance with guide levels requires continuous systems with high operation and maintenance costs that limit their application. Lichens are effective bioindicators of air quality, since changes in their diversity can be a consequence of the interaction between habitat loss and pollution. In this work it is presented a preliminary evaluation of diversity and cover of lichen communities in two types of ecosystems corresponding to urban areas and native forests with low-impact livestock in the department of Uruguay, province of Entre Ríos, with the objective of establishing a baseline to evaluate the air quality in the city. For this purpose, an ecological survey was carried out, for which three transects were arranged on which 10 phorophytes were selected in each zone. Sampling was carried out using a 20x20 cm grid to determine the frequency of the species and the total coverage of lichens. Samples of each species were taken for laboratory identification and environmental characteristics were recorded. The average species richness was 4 species per tree in the urban area and 12 in the native forest, while the cover was13% to 54% on average, respectively. Regarding the dominant species, Candelaria concolor predominated in urban areas and Crespoa crozalsiana in native forest. A strong impoverishment of the community of epiphytic lichens in the city was observed, being able to infer the impact of the activities that are developed.