IMPACT OF LAND USE SYSTEMS ON SOIL MACROFAUNA DIVERSITY AND ABUNDANCE IN NJALA, SIERRA LEONE

The study presents data on the diversity and abundance of soil macrofauna in Njala, Sierra Leone. Four different land use systems, including secondary forests, polyculture farms, oil palm plantations, and annual crop fields, were sampled for soil macrofauna using three different sampling methods: soil monoliths, line-transect protocols, and pit-fall traps. Earthworms, termites, and ants together made up nearly 94% of all soil macrofauna collected. The diversity and distribution of these three ecologically distinct groups of soil macrofauna were compared. Estimated species richness (diversity) was highest in the oil palm plantation (p<0.001) as compared to the other three land uses. The number of individual macrofauna collected (out of 1728 total) was highest in the secondary forest (215 ? 0.18, p<0.001) than in the oil palm plantation (163 ? 0.18), the polyculture farmland (113 ? 0.86), and the annual maize plantation (86 ? 0.65). For the various macrofauna species recorded, there were significantly more earthworms (Oligocheate) (0.6864 ? 0.21 individuals/m2, p<0.001) than termites, especially Amitermes hastatus (0.4032 ? 0.11 individuals/m2), Macrotermes mossambicus (0.3648 ? 0.04 individuals/m2), Macrotermes natalensis (0.3552 ? 0.25 individuals/m2), and Microhodotermes viator (0.3024 ? 0.29 individuals/m2). Besides secondary forests, monoculture plantations would be better areas for conservation of not only of aboveground biodiversity, but also of belowground biodiversity.