Climatic factors and livestock affect richness of Dung beetles (Scarabaeinae) in subtropical forests of Argentina

ZURITA, G.A.; GUERRA ALONSO, C.; BELLOCQ, M.I.

Simposio; 3er International Symposium of Ecology; 2018

The objective of this study was to assess changes in the richness of dung beetles in relation to the native forest in livestock systems in subtropical forests of Argentina and to relate these changes to environmental conditions. Dung beetles were sampled in the native forest and two livestock systems (with and without canopy cover), in three subtropical forests differing in environmental conditions (Atlantic forest, humid and dry Chaco). In each region, five sampling sites were selected for each habitat with 10 pitfall per sampling site. In order to describe vegetation structure four variables were estimated: bare soil and the cover of herbaceous, shrub, canopy and and litter cover. Also temperature and humidity at the ground level were recovered. Trough general linear models and PCA, richness among sites was compared and the role of environmental variables. A total of 110 species were collected. Richness differed among open pasture and native forest and silvopastoral system in the Atlantic forest and the humid Chaco, however for Dry chaco richness was similar among habitats. Annual mean temperature, thermal daily amplitude, seasonality in precipitations, maximun temperature were associated with dry Chaco, whereas native forest and silvopastoral system in the Altantic forest and humid Chaco were associated with average humidity and canopy cover and sites of open pasture del Native forest and Humid chaco, were associated with average temperature. In general, livestock systems reduce dung beetle richness in the Atlantic forest and humid Chaco, due to climatic variables and the lack of canopy coverage associated with these systems, while for the Dry Chaco, no significant differences were found in terms of richness between the native forest and livestock systems.