POPULATION-DYNAMICS OF EARTHWORMS DURING CROP-ROTATION UNDER RAIN-FEDAGRICULTURE IN CENTRAL HIMALAYAS, INDIA

The density and seasonal distribution patterns of three to five earthw orm species was observed in relation to crop rotations during a period of 2 years in three localities ((a) Sun temple site; (b) Small tank s ite; (c) Dak bunglow site) in the rainfed upland agricultural system o f central Himalayan district of Almora, India. Earthworm species compo sition at Sun tample site was different from the Dak bunglow site and Small tank site. Drawida sp. was dominant at the Sun tample site where as Lennogaster yeicus and Metaphire holutii were dominant at the Dak b unglow site. Maximum earthworm density (200 m(-2)) was recorded in the late rainy season in the rice crop mixture and in Eleusine coracana ( finger millet) crop mixture (335 m(-2)) sown following the harvest of winter wheat crop. Ploughing, harrowing and cult-discing the soils in the agricultural system during crop rotation had adverse effect on ear thworm species populations. Ploughing back of crop byproducts along wi th the addition of the organic manure encouraged increase in the earth worm populations. (C) 1997 Elsevier Science B.V.