Determinación de la concentración de material particulado sedimentable proveniente del tráfico vehicular en la vía Cuenca-Molleturo y su impacto sobre la vegetación arbustiva en El Parque Nacional Cajas

Abstract

Cajas National Park (PNC) is located west of Cuenca, Azuay. It is a protected area due to its high ecological richness, becoming a natural hydric regulator. The Cuenca – Molleturo highway crosses the PNC, presenting a high vehicle flow since it is the main connection between Guayaquil and Cuenca, supporting both cities’ economic development. Vehicular traffic releases atmospheric pollutants such as combustion gases or particulate matter (PM 10, PM 2,5 and sedimentary matter), which affect local vegetation in the process of photosynthesis, respiration and transpiration; causing an apparent decrease of endemic biodiversity. The present research is focused on determining the effect of dustfall on the richness and abundance of vegetation, therefore, five main monitoring points were set up along the highway and six transversal points were set to a distance of 50, 150 and 250 meters from both edges of the road (left and right), where dustfall concentration, species richness, and individuals abundance of shrub vegetation were determined for subsequently getting a Spearman correlation between these variables. None of sedimentary material’s concentrations found in the study area exceeded the maximum allowable limits by the Unified Text of Secondary Environmental Legislation (TULSMA), showing the highest concentrations in the points closest to the road. The sampled transects presented high Shannon diversity index values and similar richness between them. Finally, the biological variables correlation with the sedimentary material concentrations showed no significant effect on the richness and abundance of shrub vegetation in the study area.