ABSTRACT

It is a common practice in Nigeria especially by motor mechanics to dispose spent oil into gutters, water drains, open vacant plots and farms. The effect of spent oil on the anatomy and heavy metal content on vigna plants was investigated as well as creating opportunity for plant breeders in searching for ways of improving cowpea production in oil producing areas. The effect of spent oil contamination was studied on three different species of vigna (Vigna dekindtiana, Vigna marina and Vigna vexillata) at four different concentrations. The four different concentrations of spent oil graded from 50%, 100%, 150% and 200% of which each treatment has three replicates. The results show that a negative relationship existed between the oil levels in the soil and the growth parameters (plant height, number of leaves, yellowness of leaves, folding of leaves and leaf drop) observed. The reductions and morphological effects in the growth and characteristics measured in the plants with spent oil increased as the concentration level of the contaminant increases compared to the control. Therefore, spent oil in soil has highly significant effects of some soil properties which include nitrogen and heavy metal properties. The oil also significantly reduced percentage germination and delayed germination as well as growth of the plants. The anatomical changes and observed heavy metal alterations in the plants and soils were discussed as a possible tool in phytomonitoring and phytoremediation. The soil and plant used for this project work were properly buried to prevent the reintroduction of the heavy metal parts of plants and soil into the food chain, since not all accumulated heavy metals are phyto extracted or completely degraded by plants.

TABLE OF CONTENT

Title page

Declaration

Certification

Dedication

Acknowledgement

Table of content

List of tables

List of plates 

Abstract

Chapter 1: Introduction

1.1 Justification

1.2 Objectives of the study

Chapter 2: Literature Review

2.1 Effect on total germination and cumulative germination

2.2 Effect of spent oil on height of plant

2.3 Effect of spent oil on leaf and girth

2.4 Effect of spent oil on chemical and mineral content

2.5 Effect of spent oil on morphology of plant

2.6 Botany of the plant

Chapter 3: Materials and method

3.1 Study area

3.2 Design of experiment

3.3 Collection of samples

3.4 Planting and soil treatment

3.5 Determination of heavy metals in plant samples

3.5.1 Plant sample 

3.5.2 Determination of Nitrogen content

3.6 Statistical analysis

Chapter 4: Results

4.0.1 The effect of spent oil polluted soil on anatomy of plants

4.0.2 Effect of spent oil on heavy metal content of vigna

Chapter 5: Discussions and Conclusion

5.1 Conclusion

References