Effects of environmental variables on the composition of ants (Hymenoptera: Formicidae) in Amazonian foothills forest

Abstract

Abiotic factors can negatively or positively affect the structure of communities; studying these factors is important to identify the causes that structure ant communities; taking into account this situation and that in the Amazon foothills region, particularly in the Putumayo department, few studies have been carried out and there is insufficient knowledge about the ecology of many species, this research was aimed to evaluate the effect of environmental variables in the assembly of ants, evaluating the hypothesis: the assembly of forest and grassland ants reflect changes in environmental variables (ambient temperature, soil temperature and relative humidity). In the municipality of Orito, in a secondary forest of the Amazon foothills and its grassland matrix, a 100 m transect was traced, locating 10 stations 10 m apart, in these, ants were sampled with: pitfall traps, corner baits: arboreal, epigeal and hypogeal, leaf litter extraction and manual capture. With the averages of the environmental variables in each station and the diversity and richness data per month of sampling, the Poisson regression analysis was performed and with the data of the morphospecies and the averages of the measured variables, the principal component analysis was performed. The results indicated that, the ants assemblages did not reflect the changes of the variables, some species responded to these patterns. Therefore, to understand the dynamics of the functioning of the ecosystems of the Amazonian foothills, it is necessary to study the biology of each species; However, it was determined that, the habitats studied share generalist species and contain exclusive species that contribute to the diversity of ants in the Amazonian foothills, consequently the sites must be conserved.

Keywords

• ambient temperature
• soil temperature and relative humidity
• forest fragment
• ants
• grassland matrix