the impact of different tillage and soil amendments on soil moisture storage, erosion and the yield

125 Pages·2015·1.57 MB·English

THE IMPACT OF DIFFERENT TILLAGE AND SOIL AMENDMENTS ON
SOIL MOISTURE STORAGE, EROSION AND THE YIELD OF MAIZE IN
THE MOIST SEMI-DECIDUOUS FOREST ZONE OF GHANA

BY
GINETTE DEMBELE
(ENGINEER IN AGRONOMY)

AUGUST, 2015
THE IMPACT OF DIFFERENT TILLAGE AND SOIL AMENDMENTS ON
SOIL MOISTURE STORAGE, EROSION AND THE YIELD OF MAIZE IN
THE MOIST SEMI-DECIDUOUS FOREST ZONE OF GHANA

A Thesis submitted to the Department of Crop and Soil Sciences, Faculty of
Agriculture, Kwame Nkrumah University of Science and Technology, Kumasi,
in partial fulfillment of the requirements for the award of the Degree of

MASTER OF PHILOSOPHY
IN
SOIL SCIENCE

BY
GINETTE DEMBELE
(ENGINEER IN AGRONOMY)

AUGUST, 2015
DECLARATION
I, hereby declare that this submission is my own work toward the Mphil 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 by the
University, except where due acknowledgment has been made in the text.

Ginette Dembélé --------------------------- ---------------------------
(Student: 20357396) Signature Date

Certified by:
Prof. Charles Quansah -------------------------- -------------------------
(Project Supervisor) Signature Date

Certified by:
Dr.Vincent Logah --------------------------- -------------------------
(Co- Supervisor) Signature Date

Certified by:
Dr. Enoch A. Osekre --------------------------- -------------------------
(Head of Department) Signature Date
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DEDICATION
This project work is dedicated to my Father Antoine Tontigui Dembélé and my Mother
Catherine Dembélé, my Sisters Natasha Maria Martine, Marcelline and her Husband
Youssouf Camara, and my Brother Jacques Robert Dembélé and his family for being the
artisan of what I am today.

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ACKNOWLEDGMENTS
I sincerely acknowledge AGRA (ALLIANCE FOR A GREEN REVOLUTION IN
AFRICA) for funding this research through the scholarship offered me. I would like to
warmly thank Prof. Robert C. Abaidoo for his support throughout the study.
I express my sincere gratitude to Prof. Charles Quansah my supervisor, for his valuable
suggestions during the execution of this study. I am very pleased to have had the
opportunity and pleasure to work with him. Throughout this study, he gave me not only
scientific insights, but a lot of encouragement as well. Consequently, I discovered the
world of research and acquired a strict methodological exposure. Thank you.
I express my gratitude to Dr. Vincent Logah, my co-supervisor for his valuable inputs
and suggestions during the study. I sincerely thank him for his editorial support and
availability.
I notably thank Dr. Bright Kofi Amegashie for his support during project planning. I am
highly grateful for his time. I honestly and sincerely thank the Faculty of Agriculture and
the Department of Crop and Soil Sciences (KNUST) and the Institut d‘Economie Rural
(IER, Sotuba) of Mali for all their unflinching supports.
I thank the Cotton Program (IER) for their support and encouragement especially Mr
Hassan Daou. I also thank Messrs Charles Dara, Caleb Melenya, Iliasso Aboubacar Dan-
Kassoua, Reverend Paul Sarpong and Bejame Coulibaly for their relevant
encouragements.

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ABSTRACT

The impact of different tillage practices and soil fertility amendments on soil loss and
moisture storage has not received the needed research attention in Ghana. A study was
conducted at the KNUST Agricultural Research Station at Anwomaso, Kumasi to
evaluate soil moisture storage and erosion under four tillage practices with some soil
amendments. This was to recommend the best soil management option for sustainable
maize production. The experiment was conducted in 2014 for two consecutive seasons
(major and minor) on a sandy loam to sandy clay loam soil (Plinthic Vetic Lixisol). The
field layout was split-plot in a randomized complete design with three replications.
Tillage practices (no tillage, plough- plant, plough-harrow plant and hoe) constituted the
main plot factor and four soil fertility amendments (100% NPK fertilizer (60-60-60 kg
ha -1) + Urea, Poultry Manure (3 t ha -1), ½ Rate of PM/ha (30-30-30 kg ha -1) + ½ Rate
of NPK Fertilizer ( 1.5 t ha -1) + ½ Rate Urea and Control) were the sub plot factor.
Three bare plot plots were included from which runoff and soil loss measurements were
made. The tillage practices had significant effects (P< 0.05) on runoff and soil loss. The
results showed that no tillage, with ½ Rate of PM/ha (30-30-30) + ½ Rate of NPK gave
higher agronomic characteristics of maize (grain and stover yield) and produced
minimum runoff and soil loss. Soil loss increased with increasing rainfall with
coefficient of determination ranging from 0.43 to 0.77 to 0. 63 to 0.74 under tillage
practices in the major and minor seasons, respectively. Tillage practices and soil fertility
amendments interacted to significantly reduce soil loss and runoff. Combinations of
plough-harrow x 100% NPK and hoe tillage x 100% NPK recorded the highest added
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benefits of -3.09 and -2.53 respectively in the major season whilst hoe tillage x ½ NPK +
½ PM produced the highest (-7.19) benefit in the minor season.

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TABLE OF CONTENTS

DECLARATION .............................................................................................................. i
DEDICATION .................................................................................................................. ii
ACKNOWLEDGMENTS .............................................................................................. iii
ABSTRACT ..................................................................................................................... iv
TABLE OF CONTENTS ................................................................................................. vi
LIST OF FIGURES ........................................................................................................ xii
LIST OF TABLES ......................................................................................................... xiii
CHAPTER ONE ............................................................................................................... 1
1.0 INTRODUCTION ................................................................................................. 1
1.1 Background ................................................................................................................. 1
1.2 General objective ........................................................................................................ 3
1.3 Specific objectives ...................................................................................................... 3
1.4 Hypotheses .................................................................................................................. 3
CHAPTER TWO .............................................................................................................. 4
2.0 LITERATURE REVIEW ........................................................................................... 4
2.1 Soil erosion ................................................................................................................. 4
2.1.1 Soil erosion by water ................................................................................................ 4
2.1.1.1 Factors affecting soil erosion by water ................................................................. 5
2.1.2 Wind erosion ............................................................................................................ 6
2.2 Effects of erosion ........................................................................................................ 6
2.2.1 On-site effects .......................................................................................................... 6
2.2.2 Off-site effects .......................................................................................................... 7
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2.3Tillage…………………………………………………………………………………7
2.3.1 Definition and purposes ........................................................................................... 7
2.3.2 Types of tillage ......................................................................................................... 8
2.3.2.1 Conservational tillage ........................................................................................... 8
2.3.2.1.1 Zero tillage ......................................................................................................... 9
2.3.2.1.2 Ridge tillage ..................................................................................................... 10
2.3.2.1.3 Zone or strip tillage .......................................................................................... 10
2.3.2.1.4 Mulch tillage .................................................................................................... 10
2.3.2.1.5 Other tillage systems ........................................................................................ 11
2.3.2.2 Conventional tillage ............................................................................................ 12
2.3.2.1 Intensive tillage systems ..................................................................................... 12
2.3.2.2 Traditional tillage ................................................................................................ 13
2.3.3 Short and long-term effects of soil tillage .............................................................. 13
2.3.3.1 Effect of tillage on soil physical properties ........................................................ 14
2.3.3.1. 1 Bulk density .................................................................................................... 14
2.3.3.1.2 Porosity and aeration ........................................................................................ 15
2.3.3.1.3 Infiltration rate ................................................................................................. 15
2.3.3.2 Effect of tillage on soil chemical properties ....................................................... 16
2.4 Effect of tillage on runoff and soil loss ..................................................................... 17
2.5 Effect of tillage on soil moisture conservation ......................................................... 18
2.6 Effect of tillage on crop yield.................................................................................... 19
2.7 Mineral and organic fertilizers use in crop production ............................................. 20
2.7.1 Effect of mineral and organic fertilizers on soil properties .................................... 21
2.7.2 Effect of mineral and organic fertilizers on crop yield .......................................... 22
2.8. Soil Characteristics................................................................................................... 23
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CHAPTER THREE ......................................................................................................... 24
3.0 MATERIALS AND METHODS .............................................................................. 24
3.1 Location of study area ............................................................................................... 24
3.2 Climate and vegetation .............................................................................................. 24
3.3Soil…………………………………………………………………………………..24
3.4 Experimental design/ treatments ............................................................................... 25
3.5 Runoff plot studies .................................................................................................... 28
3.5.1 Design of runoff plots ............................................................................................ 28
3.5.2 Collecting trough .................................................................................................... 28
3.5.4 Drainage ................................................................................................................. 29
3.6 Fertilizer and poultry manure application ................................................................. 29
3.7 Agronomic practices ................................................................................................. 29
3.8 Collection of data ...................................................................................................... 30
3.8.1 Runoff volume ....................................................................................................... 30
3.8.2 Direct weighing of soil loss.................................................................................... 30
3.8.3 Crop growth rate .................................................................................................... 30
3.8.4 Crop yield ............................................................................................................... 31
3.9 Soil physical analysis ................................................................................................ 31
3.9.1 Determination of soil bulk density ......................................................................... 31
3.9.2 Gravimetric moisture content (%) .......................................................................... 32
3.9.3 Volumetric moisture content .................................................................................. 32
3.9.4 Soil moisture storage .............................................................................................. 33
3.9.5 Total porosity and aeration porosity ...................................................................... 33
3.9.6 Soil depth reduction due to soil loss ...................................................................... 34
3.10 Soil sampling, preparation and analysis .................................................................. 34
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