Evaluación de la capacidad bioacumuladora de contaminantes en líquenes, utilizados en el monitoreo de la calidad del aire de la parroquia San Carlos, cantón La Joya de los Sachas, provincia de Orellana.

Abstract

The objective of this degree work is to evaluate the air quality using lichens as bio-indicators and correlating them with the concentration of heavy metals; thus, demonstrate their bioaccumulation capacity. In the first approach of the research, 15 monitoring stations were established within the 60 EP-PETROAMAZONAS block. At each station, 5 trees of the Cedrela odorata species were collected applying the lichen mapping method combined with the calculation of the Index of Atmospheric Purity (IAP). The recorded IAP values were 16,55 in the Station N° 12 (very high pollution) and the highest value 290,62 in the Station N° 5 (no pollution). In the identification of lichens, a total of 18 species was found, of which 9 are foliose, 6 crustose and 3 fructose. The leafy types presented a higher frequency of lichen species, so Parmotrema dominicanum was used as a bio-indicator of heavy metal contamination. The elements were quantified by atomic absorption spectrometry and it was determined that the chromium (3,58 mg / kg), cadmium (2,26 mg/kg), arsenic (0.071 mg / kg) and mercury (0,075 mg / kg) of lichen in the station with low IPA are in higher concentration than those from the station with high IPA. Therefore, it is concluded that the air pollution in the San Carlos parish is determined by the oil activity; mainly, by the burners in the extraction wells, which expel pollutants into the atmosphere and are bio-accumulated by the lichens.