Shallow lakes are aquatic ecosystems that span a wide variety of communities. Among these, the zooplankton community is one of the main ones that plays a fundamental role in the structuring of food webs. The regulation of the zooplankton community in the food webs is made of predation by fish and macroinvertebrates. Fish prey on active swimming, preying on all prey they can see. While shrimps are more opportunistic, they live in association with macrophytes and prey on smaller, slow-moving zooplankton species. Therefore, the predation phenomenon in the zooplankton community is not only associated with the way the predator captures the prey, but also with the self-characteristics of the prey, such as morphological, physiological and behavioral traits, which characterize its functional traits. Given this, the project aims to evaluate the effect of predation by fish and macroinvertebrates on the functional diversity of the zooplankton community in subtropical shallow lakes. To achieve this objective, samples obtained from experiments conducted by Dr. Carlos Iglesias, which were performed in lakes Blanca, Nutria and Diario, will be used and consisted of the assembly of mesocosms with four distinct treatments: Treatment only with plankton fish (P), macroinvertebrate only treatment (INV), treatment with both predators (P + INV), and treatment without any predators (CON). Two collections were performed, one at the beginning and one at the end of the experiment (49 days). In both collections will be compared the changes in the functional diversity of zooplankton. Species will be counted, identified to species level and classified according to their functional traits. For statistical analysis, differences in functional group abundances and functional diversity indices between treatments will be tested for data normality by the Shapiro-Wilk test, when necessary they will be subjected to data normalization by log (x + 1 ). Subsequently, analysis of variance (ANOVA) may be performed followed by post hoc test for parametric data. Nonparametric data will be evaluated by the Kruskal-Walis comparison test.
News published in Agência FAPESP Newsletter about the scholarship: