Cerrado physiognomies in a protected area determine the distribution of necrophagous Diptera

The landscape of the Brazilian Cerrado has been modified by human actions in the last decade with a significant increase in fires. Despite efforts to delimit an area for biodiversity conservation, human pressure on the landscape surrounding these units can affect the local environmental condition. We assessed the effect of landscape factors and fire occurrence on necrophagous Diptera diversity in different vegetation physiognomies of the Cerrado region in Chapada das Mesas National Park. We sampled in 35 sites in five physiognomies of the Cerrado biome (Open Forest or Cerradão, Dense Woodland, Gallery Forest, Park Woodland, and Woodland) using 350 traps to capture the Diptera specimens. We observed lower dipteran abundance and richness in the Gallery Forest compared to other physiognomies, and the species composition differed from all other physiognomies. Specifically, five species of Diptera were predominantly found in Open Forest or Cerradão, two species in Park Woodland, and one in Gallery Forest. The presence of species with generalist habits in forested physiognomies and the low abundance of expected forest-associated species in forest habitats suggests a decline in environmental quality in these areas. This serves as a warning sign for the ecological conditions of the Park’s predominantly forested physiognomies. Our results highlight that despite the biodiversity of necrophagous dipterans observed in CMNP, ongoing fire frequency and anthropic activities within the park could severely undermine its ability to preserve Diptera biodiversity. Consequently, environmental agencies must intensify monitoring efforts and implement effective measures to mitigate human-induced impacts in this Brazilian Cerrado conservation unit.