Temporal Beta Diversity of Local Zooplankton Communities in Small Reservoirs is Associated With Hydrological Seasonality

ABSTRACT The variation in local community structure over time—temporal beta diversity—is likely to depend on drivers similar to those used to explain spatial beta diversity. For example, in parallel with the expected relationship between geographic distance and spatial beta diversity, the longer the time between two sampling campaigns, the higher the temporal beta diversity. Also, similar to the expected relationship between environmental distance and spatial beta diversity, the higher the environmental variability between two points in time, the higher the temporal beta diversity. We sampled 39 small reservoirs in the Brazilian Cerrado in four periods (two dry and two rainy periods) to test the relationships between temporal beta diversity of zooplankton communities and the following explanatory variables: environmental variability, area, percentage of remaining vegetation, number of small reservoirs nearby, and average phytoplankton density. We calculated temporal beta diversity (TBI) and used a generalised least squares model (GLS) to test the relationship between TBI and the explanatory variables. We found high values of temporal beta diversity for different zooplankton groups. Temporal beta diversity was also highly variable between reservoirs. The transitions between the rainy and dry periods and between the dry and rainy periods were mainly characterised by gains and losses of abundance, respectively. However, the explanatory variables tested were not consistently correlated with temporal beta diversity. Our results suggest the importance of seasonal variation in climate and hydrology on the dynamics of local zooplankton communities. However, they also indicate that our knowledge about the spatial determinants of temporal beta diversity for zooplankton is limited.