Land‐use change in the Amazon decreases ant diversity but increases ant‐mediated predation

Abstract

1. Food production in Amazonian traditional societies often occurs through shifting cultivation that uses few pesticides and relies on ecosystem services provided by natural enemies. However, these sustainable agricultural practices are being threatened by increasing livestock and mechanised agriculture.2. This study aimed to evaluate the effects of the conversion from Amazon Forest to anthropogenic land uses (shifting cultivation and pasture) on αand β-diversity, functional groups, and ant-mediated predation.3. Three types of habitats were sampled: forest (eight sites), shifting cultivation (five sites) and pasture (seven sites). The ant assembly of each site was sampled using pitfall traps in the epigeic and hypogeic strata. Beetle larvae were used to evaluate the predation function.4. Negative effects on epigeic ants and functional groups were found to be greater in sites where anthropogenic land use was more intensive (pasture) than in those where it was less intensive (shifting cultivation). Furthermore, this change increased the predation of insects in shifting cultivation and pasture compared to that in forest. This increase in insect predation was due to high activity of Ectatomma brunneum Smith, 1858, an environmental indicator for shifting cultivation and pasture.5. The increase in the number of predations in shifting cultivation and pasture may be beneficial from the perspective of biological pest control. However, this relationship needs to be better understood because the high presence and predatory activity of Ectatomma brunneum in these environments may be one mechanism by which αand β-diversity decrease through antagonistic interactions and dominance.

Spatial and temporal variation of the Formicidae assemblage in different forest types of the Chaco Seco ecoregion, Argentina

“…Following the same trend, Neoponera villosa were found mainly in the pure stands, but especially in the mesquite tree stands. As mentioned by other authors, the simplification of environments induces changes in a series of environmental factors that affect the local invertebrate community; in the case of predatory ants, this simplification generates a selection in favor of those with generalist habits (Wilker et al 2023). According to Schmidt and Shattuck (2014), N. villosa is a generalist arboreal species, which is consistent with the great diversity ₃₃ of arthropods that can be found in the tree canopy (Diodato and Fuster 2016).…”

“…According to Schmidt and Shattuck (2014), N. villosa is a generalist arboreal species, which is consistent with the great diversity ₃₃ of arthropods that can be found in the tree canopy (Diodato and Fuster 2016). Along the same line, Brachymyrmex patagonicus, which was observed mainly in the stands of mesquite and eucalyptus, is also frequently cited as an indicator of highly simplified environments, preferring open habitats with development of herbaceous species (Martínez et al 2011;Wilker et al 2023) and are common ground and leaf litter dwellers, frequently associated with legumes (Fernández 2003;Fuster 2006), which could explain the results presented here.…”

Ground-dwelling ant diversity in forests and agricultural land use at Sakaerat Biosphere Reserve, Thailand

“…Interestingly, DDF and DEF highlighted unique species not detected in AG. These results were likely associated with the natural phenomenon that ant diversity and communities are influenced by habitat type, vegetation management, and effects of culture establishment (de Castro Solar et al 2016;Narváez-Vásquez et al 2021;Wilker et al 2023).…”