Effects of soil properties on arthropod biodiversity in dumpsites in Ibadan, Oyo state, Nigeria

Abstract: The impact of soil properties, temperature and relative humidity on arthropod species composition,

abundance and diversity was investigated in Apete and Aba-eku dumpsites and in a control site in Ibadan, Oyo state,

Nigeria. Ten 250g size pitfalls one third filled with 5% formalin were placed in each point in order to trap and

preserve the arthropods. The arthropods trapped in each pitfall were preserved in separate specimen bottle

containing 70% ethanol before identification. A total of 20 soil samples were collected from the sites using Auger

and analyzed for particle size distribution, bulk density, moisture content, water holding capacity, porosity, organic

matter, pH, total nitrogen, available phosphorus, potassium, calcium in (mol/kg-1) and available iron and zinc in

mg/kg-1. Analysis of variance (ANOVA) and Duncan’s multiple range test (DMRT) were conducted to compare the

mean values of the soil properties and arthropods abundance. A total of 4,763 arthropods were recorded belonging to

17 orders. Twenty six families of arthropods containing 31 species were recorded in Aba-Eku, while 24 families

with 24 species were encountered in Apete and 19 families with 21 species were recorded for the control site. Soil

parameters examined showed significant difference (p>0.05) across the three sites. The high percentage abundance

of Dipterans (Musca domestica) and heavy metal recorded, Zinc and Iron indicates that the environments were

polluted. Pearson correlation coefficient (r) showed negative correlation for the relative humidity and temperature to

the arthropods abundance. The distinct taxa found in Apete and Aba-eku suggest that the organic input from

residential areas around the dump sites favoured their abundance.