Succession of zooplankton in a Mediterranean pond using taxonomic and functional approaches

Habitat restoration offers a unique opportunity to recover biodiversity and study ecological processes in new habitats, such as successional changes in communities. In new habitats, an increase in species richness over time and a decrease in beta diversity between consecutive samplings are expected, and several ecological mechanisms can drive these temporal variations. An approach using functional traits can reveal how communities are assembled through time. Therefore, we aimed to assess temporal patterns in both taxonomic and functional (trait-based) composition and diversity of zooplankton in a newly created permanent pond, exploring the succession patterns and the underlying ecological mechanisms over 4 hydrological years. We collected zooplankton samples every 2 months over the first 4 years after an interdunal pond was created. We estimated a set of taxonomic and functional indices, including Hill numbers, functional richness, dispersion, specialization and redundancy, and taxonomic and functional beta diversity. Their trends over time were analyzed as well as the relationship with environmental variables and the correlation among them. The results showed an increasing trend in taxonomic diversity along the 4-year succession. Regarding beta diversity between samplings, a decreasing trend was observed for taxonomic and functional values. Measured local environmental conditions played a minor role in driving variations in both community and traits assembly, but the role of unmeasured variables, biotic interactions, and regional processes cannot be dismissed. Functional indices provided complementary information to the taxonomic indices: the positive correlation between taxonomic and functional richness indicates that arriving species are adding novel combinations of traits to the communities.