Data from: Evaluating community effects of a keystone ant, Azteca sericeasur, on Inga micheliana leaf litter decomposition in a shaded coffee agro-ecosystem

Our research examined the effect of Azteca sericeasur, a keystone arboreal ant, on the decomposition of leaf litter of the shade tree, Inga micheliana, in coffee agro-ecosystems. This interaction is important in understanding the spatial heterogeneity in decomposition. We hypothesized that A. sericeasur could affect leaf litter decomposition by excluding other ants, which could release decomposers, like collembolans, from predation pressure. Determining the relative strengths of these interactions can illuminate the importance of A. sericeasur in decomposition and nutrient cycling processes. We assessed the ant and arthropod communities surrounding 10 pairs of trees, where each pair included one shade tree with an established A. sericeasur nest. Tuna baits were used in conjunction with pitfall traps to assess the ant and arthropod community, and litterbags with I. micheliana leaf litter were used to assess decomposition. The species richness of ants did not change in proximity to A. sericeasur nests, though the ant communities were distinct. Abundance of collembola and community composition of other invertebrates did not change with the presence of an A. sericeasur nest and there were no differences in leaf litter decomposition rates. This contradicts past studies that suggests A. sericeasur reduces species richness in its territory. We suggest that other ants may avoid A. sericeasur by moving within and beneath the leaf litter. Our results indicate there is no net effect of A. sericeasur on leaf litter decomposition.

本研究探讨了关键类树栖蚂蚁（keystone arboreal ant）Azteca sericeasur对咖啡农业生态系统中遮荫树Inga micheliana叶凋落物分解的影响。这一物种互作关系对于理解凋落物分解过程的空间异质性具有重要意义。我们提出假说：A. sericeasur可通过排除其他蚂蚁，从而解除弹尾虫（collembolans）等分解者面临的捕食压力，进而影响叶凋落物分解过程。明确此类互作的相对强度，有助于阐明A. sericeasur在凋落物分解与养分循环过程中的重要性。本研究对10组成对样树周边的蚂蚁与节肢动物群落进行了调查，每组样树均包含1株定殖有A. sericeasur蚁巢的遮荫树。研究采用金枪鱼诱饵结合陷阱诱捕器调查蚂蚁与节肢动物群落，并利用放置有I. micheliana叶凋落物的凋落物袋评估凋落物分解速率。结果显示，尽管蚂蚁群落组成存在显著差异，但A. sericeasur蚁巢周边的蚂蚁物种丰富度并无显著变化；弹尾虫的个体丰度以及其他无脊椎动物的群落组成，并未因A. sericeasur蚁巢的存在而发生改变，叶凋落物分解速率也未出现显著差异。这一结果与以往认为A. sericeasur会降低其领地内物种丰富度的研究结论相悖。我们推测，其他蚂蚁可能通过在凋落物层内部及下方活动来躲避A. sericeasur。本研究结果表明，A. sericeasur对叶凋落物分解并无净效应。