Observations on Earthworm Communities and Soils in Various Natural and Man-Affected Ecosystems

Abstract

Earthworms are important members of the soil fauna since they regulate fundamental soil functions such as organic matter breakdown, fertility, structure and water balance. However, so far, their community assemblages have been poorly investigated in Greece. In this context, the earthworm communities of forty five sites in Greece, belonging to three types of ecosystems—terrestrial water bodies, undisturbed (natural) sites and cultivated (agricultural and urban) fields—were investigated using the combined method of digging and hand sorting followed by the application of a 0.4% formaldehyde solution. Specific soil parameters and various environmental characteristics were examined as potential factors affecting the abundance and species richness. The results showed no statistically significant difference between ecosystem densities. The species number was significantly different between ecosystems, with the cultivated fields exhibiting richer communities, with a mean of 5.3 ± 0.6 species per site compared to the natural areas with 2.4 ± 0.5 species per site, while the water bodies showed intermediate numbers (3.6 ± 0.5 species per site). Finally, earthworm densities were positively correlated with species number and percentage vegetation cover and negatively with clay. These results may contribute to understanding how different land uses affect earthworm communities.

Keywords

• earthworm communities
• natural ecosystems
• cultivated fields
• terrestrial water bodies
• environmental factors