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segments of sexually mature individuals. Further details of earthworm biology can befound in (Edwards and Bohlen 1996).Earthworm occurs worldwide in most areas where water and temperatures are favorablefor at least part of the year (all but desert and polar conditions). Across this rang ofhabitats, earthworms’ display a wide array of morphological, physiological, andbehavioral adaptations to environmental conditions. The abundance of earthworms acrosshabitats is highly variable, depending on climatic and edaphic conditions, ecosystemtype, and the degree to which the habitat has been altered, for example by agriculture.Under suitable conditions, soil C concentration has been shown to be highly correlatedwith earthworm population density and biomass (Edwards, 1983; Hendrix et al., 1992).In additions, earthworm species can be classed in one of three morpho-ecologicalgroupings that are Epigeic, Endogeic and Anecics (Bouche, 1977).Epigeic species live in organic horizons and ingest large amounts of undecomposed litter.These species produce ephemeral burrows into the mineral soil for short periods only.They are relatively exposed to climatic fluctuations and predator pressures, and tend to besmall with rapid generation times. A common example is Eisenia foetida (redworm,manure worm) which is used in vermicomposting (Bouche, 1977).Endogeic species forage below the surface, ingest large quantities of soil with apreference towards organic rich soil, and build continuously ramifying burrows that aremostly horizontal. These species are apparently not of major importance in litterincorporation and decomposition since they feed on subsurface material. They are17