Variación cualitativa y cuantitativa de fitoplancton en estanques durante la etapa de engorde de cultivo de camarón blanco (litopenaeus vannamei)

Abstract

In semi-closed aquaculture systems for the production of L. vannamei, microalgae play a fundamental role in the production of oxygen through the photosynthesis, being at the same time a potential food source, which highlights their presence for the ecological balance of the ponds. Phytoplankton in a pond can be composed of various microalgal groups, and develop in all aquatic ecosystems in response to various physicochemical factors, therefore, the objective of the present study was to evaluate the qualitative and quantitative variation of phytoplankton in aquaculture ponds. In order to fulfill this objective, data were recorded from 3 ponds during a shrimp farming cycle, in the shrimp farm “SATUKIN S.A” located in Yaguachi, province of Guayas. Both microalgae type and concentration were identified and quantified, respectively. The main groups present were chlorophytes, cyanophytes, diatoms, dinoflagellates (and others), which were identified by means of microscopy techniques, which included identification guides for phytoplankton, and a Neubauer chamber. As a counterpart, data on the concentration of both N and P were obtained by means of spectrophotometry, as well as the N:P ratio. Furthermore, the incidence of N and P on the phytoplanktonic composition and concentration was evaluated. The results showed a seasonal variation in the composition of phytoplankton throughout the culture period of L. vannamei, where chlorophytes and cyanophytes where the dominating groups in the ponds, with variations in their abundance related to the N:P ratio. These results highlight the complex interaction between nutrients and microalgae in aquatic systems, and their importance for understanding and managing the water quality in aquatic ecosystems.