Residential sites increase species loss and cause high temporal changes in functional diversity of dung beetles in an urbanized Brazilian Cerrado landscape

Urbanization is increasing globally and causing rapid taxonomic and functional changes in biological communities. Its effects through time in the same communities have not been addressed properly. Here, we evaluate the temporal changes in taxonomic and functional diversity of dung beetles between greenspace (Cerrado stricto sensu) and residential sites in an urban landscape in the Brazilian Cerrado. We sampled dung beetles across 3 years (2013-2015) during the rainy season in the same sites. We evaluated these temporal changes using Temporal Beta Index and beta diversity partitioning into its components of replacement and gain/loss. We expected that residential sites will be taxonomically and functionally poorer compared to greenspace sites over the years. We found a general loss of species and abundance-per species from 2013 to 2015, which was more pronounced in residential sites than greenspace sites, since greenspace sites showed some gain of species from 2014 to 2015. Functional richness, functional evenness, and functional divergence did not change over the years, but were always lower in residential sites than greenspace sites. Functional beta-diversity did not change over the years, but was always higher in residential sites than greenspace sites, with similar contribution of functional replacement and nestedness-resultant components. We demonstrate that greenspace sites are taxonomically and functionally more stable, temporally, than residential sites. Implications for insect conservation We advocate that public policies aimed at conservation and management of greenspace sites are important tools for maintaining dung beetle diversity and their ecosystem functions in urbanized landscapes in the Brazilian Cerrado.