Trophic status of twenty-four water reservoirs in the eastern of Cuba

Abstract

Trophic status of twenty-four water reservoirs of the eastern of Cuba was evaluated, classifying these reservoirs according to the eutrophication level. The average trophic state index (TSI) was calculated considering chlorophyll a, transparency and total phosphorus. A cluster analysis with TSI values allow to establish five eutrophic levels with specific ranges and attributes, modifying the classical Carlson criteria. The most eutrophic reservoirs were Chalóns and Camazán (level 4). It was confirmed direct relationship between eutrophic and cyanobacteria bloom occurrence, being the most contaminated those with higher risk. Toxic bloom-forming species were detected in Parada, Baraguá, La Yaya, Mícara, Bio and Guisa, Chalóns and Camazán, involving cyanobacteria like Synechocystis aquatilis, Cylindrospermopsis raciborskii, Oscillatoria sp., Microcystis aeruginosa, M. flos-aquae, M. panniformis, M. wesenbergii, Planktolyngbya limnetica, and Synechococcus sp.