摘要:The present study analyzes Octolasion (Oligochaeta Lumbricidae) and Octolasion lacteum species in terms of biomass dynamics and biological productivity at different soil levels (from 10cm to 40cm) in three hilly forest areas of Cande ti Piedmont, A rges County, in the period March October 2008. This species belongs to the group of endogeic species with an important role in mixing organic mineral soils and is considered eudominant with the most important role in the functioning of forest ecosystems. The results showed that the monthly biomass of the soil levels in the three areas ranged from 0.57 3.221 mg.d.s/m2 in the deciduous forest, 0.22 0.492 mg.d.s/m2 in the spruce forest and 0.67 2,389 mg.d.s/m2 in the grassland. The deciduous (20.155 mg.su./m 2 ) and the grassland forests (22.643 mg.su./m 2 ) had the highest biological productivity