Effect of land use change on Melolonthidae (Coleoptera: Scarabaeoidea) beetle communities in the deforestation arc of the Brazilian Amazon

Although Amazon provides crucial goods and ecosystem services for
humanity, the alarming conversion of its original ecosystem due to
agricultural activities challenges the maintenance of biodiversity in this
rainforest. Beetles from the family Melolonthidae serve as a proxy for
assessing the effect of land use change on biodiversity. In this study, we
evaluated the effect of land use changes on the entire Melolonthidae
community (species richness, abundance, and biomass) and on each subfamily
(Rutelinae, Melolonthinae, and Dynastinae). Peach palm Bactris gasipaes
Kunth (Arecaceae) plantation, coffee Coffea canephora Pierre ex A.
Froehner (Rubiaceae) plantation, pasture Urochloa decumbens Stapf.
(Poaceae), Forest remnants had their Melolonthidae communities assessed in
a southern Amazon region. Forest remnants encompassed a higher species
richness of the Melolonthidae and Rutelinae compared to the other
habitats, while pasture areas had a higher abundance of Melolonthidae,
Dynastinae, and Melolonthinae, as well as a higher biomass of the last
group. Coffee plantation presented the lowest species richness, abundance,
and biomass for all taxonomic levels studied. The results provide evidence
that the Melolonthidae beetle community, especially Rutelinae, is
negatively affected by land use change in the Amazon, reinforcing the role
of these beetles in conservation studies. Pasture areas are favorable
habitats for some species of the Dynastinae and Melolonthinae subfamilies,
which suggests that they may be pests in this ecosystem. Future population
studies are necessary to broaden our understanding of this group of
insects.