UTTAR PRADESH JOURNAL OF ZOOLOGY

Earthworms are important ecosystem engineers that improve soil fertility, nutrient cycling, decomposition, and soil structure in terrestrial ecosystems. Understanding their population dynamics and relationship with abiotic factors is essential for assessing soil health and biodiversity in forest ecosystems such as the lateritic semi-evergreen forests of Kolli Hills. This article provides a detailed account of the population of five species of earthworms, namely Drawida gracilis, Drawida bullata, Hoplochaetella stuarti, Megascolex cochinensis, and Pontoscolex corethrurus, in terms of numbers, biomass, abundance, density, and relative density. This article also deals with the ecology of earthworms in detail, in general, and abiotic factors in particular. The results of the present study show that all five species of earthworms enumerated during the first year of study (June 2009 to May 2010) were comparatively lower than those in the second year (June 2010 and May 2011). The change in earthworm populations might be attributed to comparatively low rainfall (893 mm) during the first year than during the second year (1865 mm). Seasonal fluctuations in soil moisture in relation to rainfall may affect the size of earthworm populations, biomass, and other analysed parameters. The observed earthworm populations were in the following order, such as D. bullata followed by D. gracilis, H. stuarti, M. cochinensis and P. corethrurus. Similarly, the mean wet biomass of the observed earthworms were in the following order viz., H. stuarti followed by D. gracilis, M. cochinensis, D. bullata and P. corethrurus.