Richness and structure of ant assemblies (Hymenoptera: Formicidae) in Atlantic forest in southern Brazil

ABSTRACT Ant diversity is influenced by the structural complexity of the environment. Ants are thus an ecologically important group due to their potential to serve as indicators of environmental quality. The objective of this study was to evaluate ant diversity in areas with different land use histories and thus, within different stages of regeneration in the Permanent Preservation Area of the Foz do Chapecó Hydroelectric Plant reservoir. Ant assemblies among sample sites were compared using rarefaction analysis, and estimated richness, frequency of occurrence, and relative abundance were calculated. Associations between species and sample sites were evaluated using Principal Component Analysis (PCA). We identified 55 species in total from 24 genera, distributed among seven subfamilies. Eight species had positive associations with sample sites. Estimates indicated that ant richness may be up to 21.4% greater than that observed. This study presents an inventory of species capable of colonizing environments undergoing natural regeneration processes, and aids our understanding of ecological recovery dynamics in protected areas near hydroelectric plant reservoirs southern Brazil.摘要 蚂蚁多样性受环境结构复杂性的影响。因此，蚂蚁凭借其作为环境质量指示生物的潜力，成为一类具有重要生态意义的类群。本研究旨在评估不同土地利用历史区域，亦即福兹杜沙佩科（Foz do Chapecó）水电站库区永久保护区内不同自然恢复阶段的蚂蚁多样性。研究采用稀疏分析（rarefaction analysis）对各样地间的蚂蚁群落进行比较，并计算了估计物种丰富度、出现频率及相对多度；同时采用主成分分析（Principal Component Analysis，PCA）对物种与样地间的关联进行评估。本次研究共鉴定出隶属于24属、7亚科的55个蚂蚁物种，其中8个物种与样地存在正相关关系。估计结果显示，蚂蚁物种丰富度最高可比实际观测值高出21.4%。本研究构建了能够定植于自然恢复过程生境的蚂蚁物种名录，有助于加深对巴西南部水电站库区周边保护区生态恢复动态的理解。