Are ant assemblages of Brazilian veredas characterised by location or habitat type?

Wetland areas in the Brazilian Cerrado, known as “veredas”, represent ecosystems formed on sandy soils with high concentrations of peat, and are responsible for the recharge of aquiferous reservoirs. They are currently under threat by various human activities, most notably the clearing of vegetation for Eucalyptus plantations. Despite their ecological importance and high conservation value, little is known about the actual effects of human disturbance on the animal community. To assess how habitat within different veredas, and plantations surrounding them affect ant assemblages, we selected four independent vereda locations, two being impacted by Eucalyptus monoculture (one younger and one mature plantation) and two controls, where the wetland was surrounded by cerrado vegetation. Ant sampling was conducted in May 2010 (dry season) using three complementary methods, namely baits, pitfall traps, and hand collection, in the wetland and in the surrounding habitats. A total of 7,575 ants were sampled, belonging to seven subfamilies, 32 genera and 124 species.Ant species richness and abundance did not differ between vereda locations, but did between the habitats. When impacted by the monoculture, ant species richness and abundance decreased in wetlands, but were less affected in the cerrado habitat. Ant species composition differed between the three habitats and between vereda locations. Eucalyptus plantations had an ant species composition defined by high dominance of Pheidole sp. and Solenopsis invicta, while natural habitats were defined by Camponotus and Crematogaster species. Atta sexdens was strictly confined to native habitats of non-impacted “veredas”. Eucalyptus monocultures require high quantities of water in the early stages, which may have caused a decrease in groundwater level in the wetland, allowing hypogeic ants such as Labidus praedator to colonise this habitat

Questioning the implementation of habitat corridors: a case study in interior São Paulo using ants as bioindicators

In this paper we operated ant collections in three inland Atlantic forest fragments and in the neighboring Edmundo Navarro de Andrade State Forest (FEENA), an Eucalyptus plantation located in Rio Claro, interior of São Paulo State. We show that the ant communities of the native forest fragments are more similar among themselves than to the ant community of FEENA. Thus we evidence that, in addition to the clear difference in vegetation segment, other components of the biota (like ants) can be different between FEENA and the native forest fragments. Our results conveniently served as a basis to discuss the proposal of connecting FEENA to the three native forest fragments by a habitat corridor. These fragments are important to conservation purposes since they represent the biggest areas of native vegetation in the region

Effects of abandoned Eucalyptus plantations on lizard communities in the Brazilian Cerrado

The rapid expansion of human altered landscapes affects biodiversity on every continent. A fundamental goal of conservation biologists is to understand why certain species are at risk of extinction while others are able to persist in human altered landscapes. Afforestation, the conversion of unforested lands to planted forest, is rapidly altering many natural landscapes worldwide. In the Cerrado (Brazilian savanna), a global biodiversity hotspot, a shortage of government incentives has the landscape riddled with abandoned plantation forests that are not subject to active restoration projects. Studies investigating the impacts of abandoned plantations on biodiversity are strikingly limited. We examine the effects of abandoned Eucalyptus plantations on the structure of Cerrado lizard communities. We assessed changes in lizard capture, richness and equitability along cerrado sensu stricto—Eucalyptus transects. Our results indicate abandoned Eucalyptus plantations have subsets of Cerrado species persisting with a great loss of endemic species. The cerrado sensu stricto—Eucalyptus linear transect analysis demonstrated distance from native habitat is positively correlated with loss of biodiversity. We performed correspondence analyses to summarize the variation in species captures across different sites, habitats and pitfall array positions. These analyses depicted strong species associations between habitats and their pitfall array positions. This study is the first to show the negative impacts of abandoned Eucalyptus plantations on Cerrado lizard communities, serving as a cautionary tale of Cerrado biodiversity non-resilience in abandoned Eucalyptus plantations. Mitigation requires that abandoned Eucalyptus plantations are made more suitable to Cerrado lizards by implementing targeted habitat heterogeneity restoration