IMPACT OF AGE OF CRUDE OIL SPILLAGE ON ARTHROPOD DIVERSITY AT VARIED SOIL DEPTHS IN PART OF NIGER DELTA, NIGERIA

Abstract

Contamination of soil from crude oil spill is a major pollution challenge in Nigeria's Niger Delta region, in order lo detect this impact, soil arthropods wore extracted using Berlese-Tullgren Funnel (dynamic) method from three locations of different ages of crude oil spill incident sites in comparison with natural controlled locality in part of Niger Delta, Nigeria for a period of two successive years. In total, 15,558 individuals belonging to 39 different species, 23 families and 7 orders were identified throughout the study period at the studied sites. Acarina and Collembola ranked the major groups among the identified arthropods in the number of families, species and abundance. Highly significant differences were detected among the study sites in species diversity, richness, evenness, dominance and abundance. Moreover, the spatial variation among the study sites established negative impact on the soil arthropods: where the controlled locality recorded the highest account of species and individuals in comparison to the polluted sites. The ages of occurrence of spill were an important factor in reflecting the diversity. This followed confirmation by results of the spatial variation of diversity between varied soil depths and similarity measure. The overall diversity of soil arthropods demonstrates the negative feedback of crude oil spillage on species composition. This negative feedback diminishes with increase in the age of crude oil spill occurrence