of earthworms and other soil fauna. The activity of soil fauna declined with
cultivation in all treatments. Because of the localized concentration of worm
activity and lack of soil disturbance, soil bulk density was generally low (by
0.1 to 0.3 g cm -3) in the vicinity of hedgerows. Increase in bulk density and
compaction under continuous cultivation have also been reported for a
similar soil in Nigeria [Aina, 1979; Lal, 1985], upland soils in Thailand
[Takahashi et al., 1983], tropical America [Weert and Lenselink, 1972] and
Hawaii [Wood, 1977].