Variación de la eficiencia de la biorrestauración con pastos, a diferentes profundidades de la rizósfera, para suelos contaminados con diesel

Abstract

In this work we studied the degradation of diesel at different depths, in the presence of grass roots. The process is compared to natural attenuation. The capacity of the vegetal species to tolerate the pollutant and the factibility of its application in a process of phytoremediation, were studied. Grass seeds were grown in soil polluted with aproximately 10,000 and 20,000 ppm diesel (dry basis). Samples of soil were analized in triplicstes, at three depths (10-15 cm, 20-25 cm and 30-35 cm) during four months. It was observed that the degradation of diesel diminished as the depth of soil increased, because it is conditioned by the generation and depth of the roots. These roots showed less biomass in function of depth, within the experimental times. The eficiencies in the soil contaminated with 10,000 ppm diesel, at different depths, were 79.4%, 77% and 67.3%, respectively. For the soil contaminated with 20,000 ppm diesel, were 77.4%, 66.2% and 36.6%, correspondingly. In natural attenuation a degradation of 30% and a volatilization within 37 and 39%, were observed.