The bacterial and fungal isolates of a diesel polluted soil in comparison to a control soil were enumerated and identified. Results obtained indicates that the control soil had higher total heterotrophic bacterial (THB) and fungal (THF) than the polluted soil, while the polluted soil had higher hydrocarbon utilizing bacterial (HUB) and fungal (HUF) than the control. The microorganism isolated included Pseudomonas, Bacillus, Micrococcus, Staphylococcus, Streptococcus, Penicillum, Fusarium, Aspergillus Mucor and Rhizopus species. This study indicates that diesel polluted soil are not suitable for agricultural purposes unless recovery is encourage through treatment.

CHAPTER ONE

1.1 BACKGROUND OF THE STUDY
Environmental pollution is a cause of major concern affecting ecosystem globally. Diesel pollution is the release of a liquid petroleum hydrocarbon into the environment due to human activity and is a form of pollution release of effluents and offshore drilling activities is adversely affecting the environment (Atlas, 1981). Oil can also be released into the environment from natural geologic seeps on the sea floor, some times killing area flora and fauna. Oil is the most common pollutant in the environment.
The Niger Delta area of Nigeria Supports a lot of petroleum exploration and exploitation activities, which had subsequently led to a wide scale pollution of its rivers, swamps and farmlands with hydrocarbon (Odokuma, et al 1992). The massive and extensive pollution of these environments constitute socioeconomic and public health hazards (kobayashi et al 1982). According to Rowell and Florence (1993) Sulphate concentrations are found to be greater in soils disturbed by oil drilling, while dehydrogenase and arylsulphatase activities are lower. Chikere and Okpokwasili (2001) pointed out that the result of these additions in an inhibition of the growth of some autochthonous flora and fauna while encouraging some others to grow, thereby destroying the biodiversity and productivity of such ecosystems.
Oil pollution in the sea or ocean has steadily increases and these cause damage to aquaculture resources by physical contamination, toxic effects and by disrupting business activities. The oil penetrate up the environment from natural oil seep. Most human made oil pollution comes from land-based activity, but public sharply on seagoing oil tankers (Michael Hogan, 2008). Inappropriate disposal of residue generated in different industrial petroleum processes has been a great concern because of the intensity of the environmental damage they can provoke. Environmental pollution defined as the unfavorable alteration of the surroundings through direct or indirect effects of changes in energy patterns, radiation levels, chemical and physical constitution and abundance of organisms is clearly reflected in the Niger Delta. The study of microorganism in relation to the environment where they are found is becoming very important since they have been found to be minute alterations around them. It is also a certainty that they adapt easily to most of these changes quite unlike most other organisms.
They effectiveness of microorganisms as agent in the destruction and recycling of organic matter in the biosphere is widely acknowledged. Microorganisms are considered to be efficient biodegraders due to their abundance (Regis 2001). Oil pollution can be categorized, ranging from very light to very heavy oils. Most oils are less dense than water and tends to float as a thing layer on the surface water. Once oil gets in the environment, it undergoes weathering which is the process that describes the physical, chemical and biological changes that occurs when oil interact with the environment.

1.2 OBJECTIVES AND AIMS

1. This study is aimed at isolating and characterizing microorganisms, associated with diesel polluted environment.
2. To determine the effects of diesel on the environment.