Characterization of the Soil Nematode Fauna of Makerere Hill, Kampala, Uganda

Abstract

Soil nematode faunal analysis is necessary to ascertain the health status of the soil ecosystem. Composite soil samples were taken at designated sites; A, B, C and D from the Makerere Hill area, Kampala and analyzed to characterize the nematode fauna status. Soil samples were collected vertically at 0-5 cm, 5-10 cm and 10-15 cm core depths with a 5 cm wide soil auger. A total of  7,900 nematodes were collected from the study out of which 1,720 (21.8%) nematodes came from 0-5 cm core depth, 5,270 (66.7) from 5-10 cm core depth and 910 (11.52) from the 10-15 cm core depth. Species diversity showed nine orders of nematodes comprising twenty four families and forty nine species. The Order; Tylenchida had eight families and twenty five species. The Dorylaimida had six families and eleven species, The Rhabditida had families and seven species. The orders; Enoplida, Desmoscolida, Monhysteriida, Chromadorida, Araeolaimida and Tetracephalida had only one family and species each. Nematode species richness and abundance were more in the sites located at the lower fringes of the hill, induced by inherent environmental characteristics that promoted organic enrichment of the soil. The top soil (0-5 cm core depth) comprised the bacterivores c-p 1 (Rhabditis spp.) and c-p 2 nematodes (Desmoscolecidae Spp.), the 5-10 cm core depth had a composite population of all the trophic guilds but dominated by specialist obligates (plant parasitic) while the wide host range obligates (Meloidogyne spp., Pratylenchus spp. and Tylenchus spp.) occurred at 10-15 cm core depth. There was a large assortment of specialist parasites; Aphelenchus spp., Aphelenchoides spp., Aphastimatylenchus nigeriennsis and Trichodorus spp., occasioned by vegetation characteristics of the study area. The study area is a compendium of divergent habitats with peculiar ecomorphological characteristics that can serve as a reference in future environmental impact evaluation studies in relation to soil nematode faunal integrity in Uganda.       Key words: Soil nematodes, species diversity, abundance, bacteriovores, specialist obligates, ecomorpological characteristics.