Propuesta de un protocolo de evaluación de la calidad ecológica de ríos andinos (CERA) y su aplicación a dos cuencas en Ecuador y Perú

Resumen

A Rapid Protocol is presented for Evaluation of the Ecological Status of Andean Rivers (CERA) localized over 2000 m.a.s.l. from the Northern Andes (Venezuela) through the Altiplano in the Central Andes (Bolivia). This protocol was used in 45 sampling sites in the Guayllabamba River Basin in Ecuador and in 42 sampling sites in the Cañete River Basin in Peru. Previously, and in order to test if the sampling stations may or not be considered reference stations, we constructed a method that assesses 24 basin attributes, hydrology, reach and riverbed and that fluctuates from 24 to 120 points; sites with values higher than 100 were considered as potential reference sites. Besides the benthic macroinvertebrats' evaluation, the river habitat and riparian vegetation were also evaluated through of the application of the indices ABI (Ríos et al., submitted), IHF (Pardo et al., 2002) and QBR-And, respectively. The convenience of the initial allocation of the reference sites was evaluated as well. These indices have been properly adapted to the conditions and characteristics of the high Andes rivers. The results obtained for both basins were compared and discussed. Through the use of the CERA protocol, the particular perturbation gradients and the natural variability of the reference sites in both countries were recognized.