Análisis de la estructura trófica de los macroinvertebrados de la cuenca del río Ambato.

Abstract

The objective of the present investigation was to analyze the trophic level of the macroinvertebrates of the Ambato river basin. The study began with a sampling which was developed in 9 points belonging to the upper, middle and lower basin of the river. In these sites the macroinvertebrate collection method was applied through the Surber Network in the river substrate and direct capture in stones. Then, the samples were transferred to the Entomology laboratory of the FRN, where, the identification of each individual was carried out by using a LEICA SAPO 1090 stereoscope in order to know the family or the group to which they belong to. At the same time, a quantitative and qualitative record was kept in a database. After that, the physicochemical index ICA NSF was estimated. Biological indices such as: Andean Biotic Index (IBA) for Ecuador and Peru, BMWP Biological Index, Sensitivity Index and EPT Index to determine water quality. Finally, a conservation proposal for the ecological status of the river was drawn up. Consequently, 1707 individuals from 16 families of macroinvertebrates were recorded, the highest level was in the middle basin and the dominant trophic group is the collector-collector (CR) and this responds to the accumulation of organic matter in the river substrate. The ICA classifies the water quality of the upper basin as mildly polluted and the middle and lower basin as excessively polluted; meanwhile, the biological indixes qualify the water quality of the upper basin as good and the middle and lower basin as bad. Therefore, it is considered that the water quality of the Ambato river is bad, determining low biological diversity, with anthropic intervention being the main cause of contamination. Post-operation investigations of the treatment plant are recommended.