Comparison of earthworm fauna in oak and spruce forests on the Western slope of Kopaonik Mountain in Serbia

Abstract

The aim of the present study was to investigate the diversity and presence of ecological categories of earthworm fauna in oak and spruce forests. We sampled a total of 96 samples (48 in oak and 48 in spruce forests) during two years of fieldwork. In total, 13 earthworm species belonging to six genera were found in the studied forests. The earthworm abundance and species richness were higher in oak forests (113 individuals/9 species) than spruce forests (82 individuals/5 species). The differences in ecological categories between the studied forests were clearly evident and expected. Namely, in spruce forests our results indicate a complete absence of anecic and endogeic species, whereas epigeic species were the most dominant. However, it seems that these patterns depend primarily on the soil type. A combination of alpha diversity index (Shannon-Weaver, Evenness, and Berger-Parker) and beta diversity (Jaccard’s coefficient of similarity) were used for determining the impact of the studied forests on the earthworm community structure. Shannon’s diversity and Shannon’s evenness indices were higher for oak forests, while the Berger-Parker index of dominance was lower in oak forests than spruce forests. As expected, Jaccard’s index of similarity showed that the earthworm community structure was clearly separated between oak and spruce forests. Overall, our results based on these indices indicate that vegetation cover and altitude strongly influence the differences in earthworm community structure in the studied forests.