EFFECT OF BIOCHAR (CHARCOAL) ON MICROBIAL COLONIZATION AND HEAVY METAL CONCENTRATION IN A POLLUTED SOIL

ABSTRACT

A study of the effect of biochar (charcoal) on microbial colonization and heavy metal concentration in polluted soil was conducted for eighth (8) weeks between September to October, during the cropping season of 2018, at the faculty of Agriculture, Kogi State University, Anyigba. The aim of the study was to determine the effect of biochar on microbial colonization and heavy metal concentration in a polluted soil. The experiment was laid out in a completely randomized design (CRD) and the data collected were subjected to ANOVA using SPSS. The study revealed lower count in bacteria and fungi in non amended polluted soil compared to biochar amended polluted soil which has higher count in both bacteria and fungi. There were significant differences at (p≤ 0.05) probability level in both count for bacteria and fungi. The result obtained suggested that the pollution by heavy metals distorted the growth of micro organism and the addition of biochar (charcoal) as an organic amendment helped to increase the number of microorganisms present in the polluted soil.The study also revealed higher concentration of heavy metals in non amended polluted soil compared to polluted soil amended with biochar which had lower concentration of heavy metals. There were significant difference at (p≤ 0.05) in the concentration of heavy metals in the polluted soil at both four (4) and eight (8) weeks. The result suggested the degree of pollution in soil is a function of the concentration of heavy metals in it and that biochar (charcoal) as an organic amendment helped to reduce the concentration of the heavy metals in such polluted soil.  

Reference                                                                                                                      52

5.2       Recommendation                                                                                               51

5.1       Conclusion                                                                                                         51

5.0       Conclusion and Recommendation

CHAPTER FIVE

4.3.3    Correlation of microbes against heavy metals                                                    49   

4.3.2    Correlation of biochar against heavy metals                                                       48

4.3.1    Correlation of biochar against microorganism                                                    47

4.3       Correlation analysis                                                                                             47

4.2.3    Heavy metal analysis at eight (8) weeks                                                             42

4.2.2    Heavy metal analysis at four (4) weeks                                                              37

4.2.1    Heavy metal analysis of pre-field soil sample                                         36

4.2       Heavy metal analysis                                                                                          36

4.1.6    Total fungi count at eight (8) weeks                                                                   33

4.1.5    Total fungi count at four (4) weeks                                                                    31   

4.1.4    Fungi count of pre-field soil sample                                                                   30

4.1.3    Total aerobic heterotrophic bacteria count at eight (8) weeks                           28

4.1.2    Total aerobic heterotrophic bacteria count at four (4) weeks                            26

4.1.1    Bacteria count of pre-field soil sample                                                               25

4.1       Microbial analyses                                                                                               25

4.0       Result and Discussion                                                                                         25

CHAPTER FOUR

3.8       Statistical Analysis                                                                                              24

3.7.1    Estimation of total heterotrophic bacteria and total fungi content                     24

3.7       Microbial Analysis                                                                                              24

3.6.1    Heavy metal analysis in soil                                                                                23

3.6       Heavy Metal Analysis                                                                                         23

3.5       Experimental Procedure                                                                                      23

3.4       Treatment and Experimental Design                                                                  23

3.3       Soil sample preparation                                                                                       22

3.2       Sample collection                                                                                                 22

3.1       Experimental Area                                                                                               22

3.0        Materials and method                                                                                                      22

            CHAPTER THREE

2.6       Microbes possessing metabolic pathway to utilize heavy metals                          19

2.5       Permissible limit of heavy metal in soil and plant                                                14

2.4       Naturally occurring heavy metal                                                                          14

2.3       Heavy metals in soil                                                                                             13

2.2       Soil composition                                                                                                  12

2.1.6    Environmental impact of biochar                                                                         12

2.1.5    Agricultural impact of biochar                                                                             11

2.1.4    Production of biochar                                                                                          11

2.1.3    Biochar as organic material                                                                                  7

2.1.2    Benefit of biochar in soil                                                                                     4

2.1.1    Background                                                                                                         4

2.1      Biochar as Amendment                                                                                       4

2.0              Literature Review                                                                                                4

          CHAPTER TWO

1.2       Objectives of the study                                                                                       3

1.1       Justification of the study                                                                                    3

1.0              Introduction                                                                                                        1

CHAPTER ONE

            Table of contents                                                                                                           VII

            Abstract                                                                                                                         VI

            Acknowledgement                                                                                                          V

            Dedication                                                                                                                     IV

            Certification                                                                                                                  III

            Declaration                                                                                                                     II     

          Cover page                                                                                                                     I

          Title page

TABLE OF CONTENTS