A thin temperature label reveals temporal changes in the zooplankton structure on a Neotropical floodplain

Temperature is a determinant factor for the distribution and structure of aquatic communities, as species have distinct ranges of thermic tolerance. Here we evaluated i) how does variation in water temperature affect the structure of the zooplankton community through time; and ii) what is the temperature threshold that alters the frequency and abundance of species. Zooplankton was sampled from 2000 to 2015 in six habitats of a Neotropical floodplain (22 degrees 40' - 22 degrees 50' S; 53 degrees 10' - 53 degrees 24'W) totaling 276 samples. We used a Threshold Indicator Taxa Analysis (TITAN) to answer our questions. We recorded 297 zooplankton species, 196 rotifers, 69 cladocerans, and 33 copepods. Temperature variation affected community structure, with a positive change (abundance increased) temperature of 29.15 degrees C, increasing frequency and abundance for most species, and a negative change temperature (abundance decrease) of 20.15 degrees C, reducing these attributes. This study is a warning of the negative impacts of climate change, where temperature is predicted to increase, on the aquatic biological communities, as some species were sensitive to high temperatures.