Limnetica 33
Periphytic diatom index for assessing the ecological quality of the Colombian Andean urban wetlands of Bogotá
Five wetlands in Bogotá (Guaymaral, Jaboque, Juan Amarillo, Santa María del Lago and Tibanica) and one rural wetland (Meridor, Tenjo municipality) were sampled four times during dry, rainy and transitory climatic periods (between 2007 and 2008). Physico-chemical variables were measured and periphyton was sampled to evaluate the diatom community. The pollution value per taxon (PVT) was established for each diatom species and a periphytic diatom index for Bogotá Wetlands (PDIBW) was calculated to evaluate the ecological quality of the wetlands. According to the limnological status thus established, the six wetlands can be classified as follows: Santa María del Lago, Meridor and Jaboque exhibit poor to moderate limnological conditions; Tibanica is in poor condition; Guaymaral has severely impaired to moderate conditions; and Juan Amarillo tends to present permanent severely impaired conditions, which indicates that it is the most polluted wetland. The index proposed was useful to classify the wetlands according to their limnological status, and it adequately represents the ecological quality of the Bogotá wetlands.