Physicochemical Foliar Traits Predict Assemblages of Litter/ Humus Detritivore Arthropods

Abstract

Plant functional traits influence the decomposition of their own residues occurring under- neath individual plant species. Arthropods associated to litter are critical components influencing decomposition. Nevertheless, few studies have established a direct relation between plant traits and belowground arthropods. To address this relation at the individual plant species scale, this study was conducted in the Guánica dry forest, Puerto Rico, by selecting five tree species and ten isolated trees/species where variations due to neighbor trees are reduced. Mature green leaves, litter, and associated arthropods were sampled from November 2004 through September 2005. Collected arthropods were counted and classified, and abundances were standardized to ind/m 2 . Arthropod abundance did not differ among plant species, but richness, and species and trophic composition were differ- ent among the plant species. Predators, omnivores, and sucking herbivores showed a similar species composition among plant species, while detritivore was the only trophic groups with a different species composition among plants. These results are further supported by canonical correspondence analysis results showing that detritivore arthro- pod species composition covaries with the physicochemical characteristics of mature green leaves of plants. These findings support that the plant idiosyncratic characteristics affect the structure of litter/humus arthropods up to the first consumer level.