KWAME NKRUMAH UNIVERSITY OF SCIENCE AND TECHNOLOGY COLLEGE OF SCIENCE DEPARTMENT OF THEORETICAL AND APPLIED BIOLOGY PHYTOREMEDIATION OF HEAVY METAL CONTAMINATED SOIL USING Thelypteris accuminata (Houtt.) C.V. Morton and Nephrolepis exaltata (L.) Schott A THESIS SUBMITTED TO THE DEPARTMENT OF ENVIRONMENTAL SCIENCE IN PARTIAL FULFILMENT FOR THE REQUIREMENTS OF MASTER OF SCIENCE DEGREE IN ENVIRONMENTAL SCIENCE BY EVELYN OWUSU-DENTAAH NOVEMBER, 2016 i DECLARATION “I hereby declare that this submission is my own work towards the MSc degree and that, to the best of my knowledge, it contains no material previously published by another person nor material which has been accepted for the award of any other degree of the University, except where due acknowledgement has been made in the text”. EVELYN OWUSU-DENTAAH ………………….. …….……………. Student’s Name Signature Date DR. EBENEZER J. D. BELFORD ……………... …. …….……………. Supervisor’s Name Signature Date ……………….. …………………….. ...………………. Head of Department Signature Date ii DEDICATION With great pleasure I dedicate this work to my supervisor, Dr. Ebenezer J. D. Belford and to one person, Francis Kwaku Nkansah to whom I am highly indebted. iii ACKNOWLEDGEMENT I would never have been able to finish my thesis without the support from my family and husband. I would like to express my deepest gratitude to my advisor, Dr. Ebenezer J. D. Belford, for his excellent guidance, caring, patience, and providing me with an excellent atmosphere for doing research. I would like to thank Franklin Kwasi Owusu, Andy Owusu Botah, Samuel Owusu Sarfo and Padmore Adusei Amoah for their support and encouragement has seen me through this programme. Special thanks goes to my wonderful and kind parents, Nana Owusu Akyaw Prempe I and Madam Margarent Adusah for their encouragement and best wishes. Not forgetting my two children, Simms Twum Ofosu Jr and Rocklyn Nhyira Ofosu your presence fill my heart with joy and enthusiasm. I would like to thank Francis K. Nkansah, who as a good friend was always willing to help and give his best suggestions. It would have been a lonely lab without him. Finally, I would like to thank my husband, Mr. Ofosu Simms. He was always there cheering me up and stood by me through the good times and bad. iv TABLE OF CONTENTS DECLARATION ............................................................................................................................ ii DEDICATION ............................................................................................................................... iii ACKNOWLEDGEMENT ............................................................................................................. iv TABLE OF CONTENTS ................................................................................................................ v LIST OF PLATES ......................................................................................................................... ix LIST OF TABLES .......................................................................................................................... x LIST OF ABBREVIATIONS AND ACRONYMS ...................................................................... xi ABSTRACT .................................................................................................................................. xii CHAPTER ONE ............................................................................................................................. 1 1.0 INTRODUCTION ............................................................................................................... 1 1.1 Background .......................................................................................................................... 1 1.2 Justification .......................................................................................................................... 2 1.3 Main Objective..................................................................................................................... 3 1.3.1 Specific Objectives ....................................................................................................... 3 CHAPTER TWO ............................................................................................................................ 4 2.0 LITERATURE REVIEW .................................................................................................... 4 2.1 Mining in Ghana .................................................................................................................. 4 2.2 Heavy Metals ....................................................................................................................... 4 2.2.1 Heavy Metal Toxicity ................................................................................................... 6 2.2.2 Specific Heavy Metal Toxicity ..................................................................................... 6 2.3 Soil Remediation Measures ................................................................................................. 9 2.3.1 Conventional Remediation Measures ........................................................................ 10 2.3.1.1 Soil Washing ........................................................................................................... 10 2.3.1.2 Vitrification ............................................................................................................. 10 2.3.1.3 Encapsulation .......................................................................................................... 11 2.3.1.4 Electrokinesis .......................................................................................................... 11 2.3.1.5 Chemical Immobilization........................................................................................ 12 2.3.1.6 Excavation and Landfill .......................................................................................... 12 2.4 Phytoremediation Techniques ............................................................................................ 13 2.4.1 Phytoextraction ........................................................................................................... 13 v 2.4.2 Phytovolatilization ...................................................................................................... 13 2.4.3 Phytostabilization ....................................................................................................... 14 2.4.4 Phytodegradation ........................................................................................................ 15 2.4.5 Phytorhizofiltration ..................................................................................................... 15 2.5 Heavy Metal Accumulation and Translocation ................................................................. 16 2.6 Selection of Plant for Phytoremediation ............................................................................ 17 2.7 Handling and Disposal of Plant Waste .............................................................................. 18 2.8 Advantages and Limitations of Phytoremediation ............................................................. 18 2.9 Total and Bioavailable Heavy Metal ................................................................................. 19 2.10 Experimental Plants Species Used in This Work .............................................................. 20 2.10.1 Thelypteris accuminata............................................................................................... 20 2.10.2 Nephrolepis exaltata ................................................................................................... 21 CHAPTER THREE ...................................................................................................................... 23 3.0 MATERIALS AND METHODS ....................................................................................... 23 3.1 Treatment Soil Preparation ................................................................................................ 23 3.2 Plant House Experiment .................................................................................................... 24 3.2.1 Collection of Planting Materials and Experimental Layout ....................................... 24 3.2.2 Harvest ........................................................................................................................ 24 3.3 Laboratory Procedures for Analysis of Plant and Soil Samples ........................................ 25 3.3.1 Plant Analysis ............................................................................................................. 25 3.3.2 Digestion of Plant Samples ......................................................................................... 25 3.3.3 Digestion of Soil Samples .......................................................................................... 25 3.3.4 Atomic absorption Spectrophotometer Analysis (AAS) of Plant and Soil Samples .. 26 3.4 Determination of Accumulation Ratio ............................................................................... 26 3.5 Determination of Bioaccumulation Factor......................................................................... 27 3.6 Determination of Percentage Reduction of Heavy Metals in Treatment Soils .................. 27 3.7 Soil Microbial Counts ........................................................................................................ 27 3.7.1