Aplicação de modelo quali-quantitativo da relação dos efeitos de fatores limitantes na dinâmica de biomassa fitoplanctônica em reservatórios do semiárido

Abstract

The growing anthropogenic impact on aquatic ecosystems has been influencing the eutrophication process. Eutrophication is a phenomenon characterized by a high concentration of nutrients, mainly phosphorus and nitrogen, which results in the increase of primary productivity, consequently in the excessive growth of algae. In eutrophic environments the variation of algal biomass is dependent on the availability of resources (light and nutrients), which may be influenced by the variation in stored volume. of these ecosystems. Thus, the objective of this study was to apply a mathematical model that encompasses qualitative and quantitative simulations, testing it for two reservoirs of the Brazilian semiarid region (Cruzeta and Passage das Traíras), assuming that light availability and water volume variation act as the main limiting factors for algal biomass growth. The results showed that the simulation showed a tendency to follow the observed data, however for the Cruzeta reservoir there was a greater divergence, to the point that the model could not calculate the algal biomass growth due to very high values. In Traíras Passage as the stored volume and depth decrease, there is an increase in the concentration of chlorophyll-a. This study shows that the availability of light along the water column associated with extreme hydrological events affects algal biomass growth, highlighting the importance of using mathematical models as a tool for more efficient monitoring and better management of water resources. semiarid region, aiding better decision-making.