Effect of quarrying activity on biodiversity: Case study of Ogbere site, Ogun State Nigeria

Abstract

This study was carried out in quarry site at Ogbere town located at Ijebu-North Local Government Area of Ogun State; with main aim of assessing the impact of the quarry activity on bio-diversity within the unexploited site. The methods used for fauna survey are both direct and indirect by line-transect, while analysis of Mueller-Dombois and Ellenberg was adopted for vegetation. The research was carried out at both dry and wet seasons in 2008. The results revealed that species mostly abundant at the site are the reptiles. These range from families like Veranidae: black cobra Naja melanloeuca, Elaphidae, Agama agama and Python with 1.8/km each. A total number of thirty two species of avi-fauna varieties were sampled at the site, ranging from different families and species mostly fund are the clusters of villageweavers Ploceus cucullatus (1.8/km), swam-palm-bulbul Thescelocichla leupleurus (1.8/km), Senegal double Spurred francolin Francolinus bicalcaratus (0.9/km), Tambourine dove Turtur tympanistria (1.8/km). Five orders and fourteen families of mammals were recorded at the site. The most abundant are the Rodentia and Viverridae families, while the order Artiodactyla and Carnivora are at the verge of extinction due to prevailing unconducive condition at the site. The forest is dominated by secondary tree-strata with Hildegardia barteri with the species occupying mainly the hilly-rocky areas. Evidence of recent disturbance of the area with the presence of farmlands of Manihot esculenta, Carica papaya, Musa spp. was significant. The Diversity Index ranged from1.6 to 2.2 while the Equitability or Evenness Index ranged from 0.12 to 0.40, with approximately 200 trees per Km². It can be concluded that the forest ecosystem of unexploited plot of quarry at Ogbere is seriously a disturbed site due to scanty natural resources (fauna and flora species) that have been impacted by quarry activity.

Key words: Quarry, pollution, environment, fauna, flora.