IMPACT OF CHARCOAL PRODUCTION ON SOIL PROPERTIES AND 

VEGETATION IN THE CENTRAL GONJA DISTRICT OF THE 

NORTHERN REGION, GHANA 

 

  

 

 

BY 

 

SALIFU WAHABU 

(10019118) 

 

 

 

 

 

THIS THESIS IS SUBMITTED TO THE UNIVERSITY OF GHANA, 

LEGON, IN PARTIAL FULFILMENT OF THE REQUIREMENT FOR 

THE AWARD OF MPHIL ENVIRONMENTAL SCIENCE DEGREE 

 

 

 

OCTOBER, 2013

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DECLARATION 

This thesis is the result of research work undertaken by Salifu Wahabu in the Environmental 

Science Programme, University of Ghana, under the supervision of Prof. Frank K. Nyame and  

Dr. Benedicta Y. Fosu-Mensah. It has never been submitted in whole or in part for any degree in 

this University or elsewhere. References to other people‟s work have been duly acknowledged. 

 

 

………………………………………….  …………………………………………. 

SALIFU WAHABU        DATE 

(STUDENT) 

 

 

 

…………………………………………  …………………………………………. 

PROF. FRANK K. NYAME      DATE 

(PRINCIPAL SUPERVISOR) 

 

 

 

………………………………………….  …………………………………………. 

DR. BENEDICTA Y. FOSU-MENSAH     DATE 

(CO-SUPERVISOR) 

 

 

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DEDICATION 

I dedicate this work to the memory of my late father, Salifu Azindow. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
 

 

 

 
 

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ACKNOWLEDGEMENT 

I am grateful to God Almighty for his favours, my life, the health and strength I have had 

throughout this programme. I am especially grateful to my supervisors Prof. Frank K. Nyame 

and Dr. Benedicta Y. Fosu-Mensah for accepting to supervise this work and for the unlimited 

guidance rendered all through the preparation and write-up of the thesis. To the management of 

the Environmental Protection Agency (EPA-Ghana), and the Institute of Environment and 

Sanitation Studies (IESS-University of Ghana), I thank you for the opportunity given me to 

further my education and all the support given me throughout my studies.  

 

To my family, I appreciate the love and support during this period, especially, my mother Adam 

Amina, my wife Mohammed Sanatu and my siblings; Fatimata, Nurudeen, Mutowakil, 

Sulemana, Nasara and Fatima (Kpabi). To my friends, Abdulai Gani, Issahaku Ben Hussein, 

Adams Alhassan, Abukari Wumbei, Musah Jafaru, Robert Akparibo and Nantogmah Sualesu, 

thank you for the support. Mr. Tetteh Ishmael Teye, I am grateful to you for the mentoring. 

Thank you Joseph Braimah Asumah for helping me during the compilation of the thesis. 

 

To my two friends and colleagues at the United Nations University- Land Restoration Training 

(UNU-LRT) in Iceland, Enock Ssekuubwa (Uganda) and Dr. Idrissa Soumana (Niger), I thank 

you for the interest you took in my work, and the guidance and contribution you have made. 

Thank you Emmanuel Tetteh (Geography Department-UG) for the maps, Prince Owusu 

(ECOLAB-UG) for the soil analysis. Thank you Mohammed Hardi M, Adam Suluem and 

Abukari Abarika, for all the field works.  

 

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ABSTRACT 

This study assessed the impact of charcoal production on soil properties, vegetation and the 

perception of charcoal producers on the environmental impacts of their activities in the Central 

Gonja District of the Northern Region, Ghana. Data acquired suggest significant differences in 

the proportions (or fractions) of clay and sand in soils sampled within 0-30 cm depth at sites of 

charcoal production referred to simply (as burnt sites) and sites with no observable indications of 

charcoal production (or unburnt sites).  Soil silt fractions from 0-30 cm and 30-60 cm depths 

were, however, quite similar at both burnt and unburnt sites. The hydraulic conductivity of soils 

from 0-30 cm and 30-60 cm depths at burnt and unburnt sites also exhibited distinct differences 

(P < 0.001) and (P < 0.029) respectively. Soil chemical properties such as potassium (P < 0.002) 

and magnesium (P < 0.011) showed significant difference at 0-30 cm between burnt and unburnt. 

There was, however, no significant difference between burnt and unburnt sites within the 30-60 

cm for same soil chemical properties, potassium (P < 0.274) and magnesium (P < 0.076). In 

terms of land use and (land) cover change in the Central Gonja District, analysis and 

interpretation of Remote Sensing and GIS data from Landsat TM images of 1990, 2000 and 2010 

suggest reduction in the pristine or original guinea savannah (woody) vegetation of the area from 

22,662 to 11,739 ha over the twenty-year period from 1990 to 2010, with grass/herbaceous and 

built-up areas increased from 23,088 to 95,148 ha and 6,355 to 81,702 ha, respectively. Even 

though charcoal production and marketing/trade are important economic activities for people in 

the district, providing income to the charcoal producers especially women, it appears to have had 

several environmental challenges in terms of deforestation, impact on soil parameters especially 

at burnt sites, bushfires and soil erosion.  

 

Keywords: Charcoal production; environment; land degradation; soil properties. 

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TABLE OF CONTENTS 

DECLARATION ......................................................................................................................... i 

DEDICATION ............................................................................................................................ ii 

ACKNOWLEDGEMENT ......................................................................................................... iii 

ABSTRACT ............................................................................................................................... iv 

TABLE OF CONTENTS ............................................................................................................ v 

LIST OF TABLES ...................................................................................................................... x 

LIST OF FIGURES.................................................................................................................... xi 

LIST OF ABBREVIATIONS ................................................................................................... xii 

 

CHAPTER ONE ......................................................................................................................... 1 

INTRODUCTION....................................................................................................................... 1 

1.1 Introduction ........................................................................................................................... 1 

1.2 Statement of the research problem ........................................................................................ 5 

1.3 Objectives of the study .......................................................................................................... 6 

1.3.1 General objective ............................................................................................................... 6 

1.3.2 Specific objectives ............................................................................................................. 7 

1.3.3 Hypotheses ......................................................................................................................... 7 

 

CHAPTER TWO ........................................................................................................................ 8 

LITERATURE REVIEW ............................................................................................................ 8 

2.1 Introduction ........................................................................................................................... 8 

2.2 Theoretical framework .......................................................................................................... 8 

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2.3 Importance of charcoal ........................................................................................................ 10 

2.4 Method of charcoal production ........................................................................................... 11 

2.5 Environmental impact of charcoal production .................................................................... 13 

2.5.1 Impact on air quality ........................................................................................................ 14 

2.5.2 Deforestation .................................................................................................................... 15 

2.5.3 Biodiversity loss ............................................................................................................... 18 

2.5.4 Impact on soil ................................................................................................................... 19 

2.5.4.1 Soil fertility and soil erosion ......................................................................................... 20 

2.6 Geographical Information System (GIS) and Remote Sensing .......................................... 21 

2.7 Impact of charcoal production on land use and land cover change .................................... 23 

2.8 Perception of charcoal producers ........................................................................................ 25 

 

CHAPTER THREE ................................................................................................................... 27 

METHODOLOGY .................................................................................................................... 27 

3.1 The study area ..................................................................................................................... 27 

3.1.1 Relief and drainage .......................................................................................................... 28 

3.1.2 Climate ............................................................................................................................. 29 

3.1.3 Soil and geology ............................................................................................................... 29 

3.1.4 Vegetation ........................................................................................................................ 30 

3.1.5 Demographic characteristics ............................................................................................ 30 

3.1.6 Economic activities .......................................................................................................... 31 

3.2 Research design ................................................................................................................... 32 

3.2.1 Selection of communities and respondents ...................................................................... 32 

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3.3 Data collection .................................................................................................................... 33 

3.3.1 Collection of soil samples ................................................................................................ 34 

3.4 Soil analysis ........................................................................................................................ 35 

3.4.1 Chemical analysis of soil ................................................................................................. 35 

3.4.2 Determination of exchangeable potassium and sodium ................................................... 35 

3.4.3 Determination of K
+
 and Na

+
 ........................................................................................... 36 

3.4.4 Determination of soil pH, electrical conductivity and hydraulic conductivity ................ 37 

3.4.5 Determination of exchangeable calcium and magnesium ................................................ 37 

3.4.6 Determination of soil carbon and organic matter content ................................................ 37 

3.4.7 Calculation of percentage carbon (% C) .......................................................................... 38 

3.4.9 Determination of soil total nitrogen ................................................................................. 39 

3.5 Soil physical properties ....................................................................................................... 40 

3.5.1 Calculation ....................................................................................................................... 42 

3.6 Land use and land cover change ......................................................................................... 42 

3.6.1 Acquisition of raw satellite images .................................................................................. 42 

3.6.2 Classification of images ................................................................................................... 43 

3.6.3 Recoding .......................................................................................................................... 44 

3.6.4 Map Composition ............................................................................................................. 44 

3.7 Data analysis ....................................................................................................................... 44 

 

CHAPTER FOUR ..................................................................................................................... 46 

RESULTS ................................................................................................................................. 46 

4.1.1Clay ................................................................................................................................... 46 

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4.1.2 Sand .................................................................................................................................. 46 

4.1.3 Silt .................................................................................................................................... 47 

4.2 Soil physical properties at burnt and unburnt sites ............................................................. 48 

4.2.2 Electrical conductivity (EC) ............................................................................................. 48 

4.2.3 Soil pH ............................................................................................................................. 48 

4.2.4 Hydraulic conductivity ..................................................................................................... 49 

4.3 Soil chemical properties at sites (or areas) of charcoal production and sites (or areas) with 

no evidence of charcoal production (“burnt” and “unburnt” sites) ........................................... 50 

4.3.1 K, Ca, Na, Mg, organic carbon, organic matter and total nitrogen contents .................... 50 

4.3.2 Potassium (K) ................................................................................................................... 50 

4.3.3 Sodium (Na) ..................................................................................................................... 50 

4.3.4 Magnesium (Mg) .............................................................................................................. 51 

4.3.5 Calcium ............................................................................................................................ 52 

4.3.6 Organic carbon ................................................................................................................. 53 

4.3.7 Total nitrogen ................................................................................................................... 53 

4.4 Correlation coefficients between analysed soil parameters ................................................ 54 

4.5 Sites without charcoal production (unburnt sites) ............................................................... 57 

4.5.1 Correlation coefficients between analysed soil parameters ............................................. 57 

4.6 Land use and land cover change in the Central Gonja District ........................................... 59 

4.6.1. Types of land use and land cover .................................................................................... 60 

4.7 Charcoal producers‟ perception of the environmental impacts of charcoal burning .......... 64 

4.7.1 Socio-demographic characteristics of charcoal producers ............................................... 64 

4.7.2 Impacts of charcoal production on the environment ........................................................ 67 

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4.7.3 Nature of charcoal production and source of raw materials in the district ...................... 68 

4.7.4 Reasons for charcoal production in communities ............................................................ 68 

CHAPTER FIVE ....................................................................................................................... 70 

DISCUSSION ........................................................................................................................... 70 

5.1 Impact of charcoal production on soil ................................................................................. 70 

5.2 Relationship between soil parameters ................................................................................. 71 

5.3 Dynamics of land use and land cover ................................................................................. 73 

5.4 Consequences of charcoal production on the environment ................................................. 74 

 

CHAPTER SIX ............................................................................................................................. 77 

CONCLUSION AND RECOMMENDATIONS ...................................................................... 77 

6.1 Conclusion........................................................................................................................... 77 

6.2 Recommendations ............................................................................................................... 79 

 

REFERENCES ............................................................................................................................. 81 

APPENDICES .............................................................................................................................. 87 

Appendix 1: Research interview guide ......................................................................................... 87 

Appendix 2: Results of analysis of soil properties ........................................................................ 92 

Appendix 3:l Relationship between soil parameters in burnt sites ............................................... 93 

Appendix 4: Relationship between soil parameters in unburnt sites ............................................ 94 

Appendix 5: Graphical relationship between soil parameters in burnt and unburnt sites ............ 95 

 

 

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LIST OF TABLES 

Table 1: Greenhouse gas emissions from charcoal production in tropical ecosystems of the world

........................................................................................................................................ 15 

Table 2: Age and sex structure...................................................................................................... 31 

Table 3: Formula for reading soil physical properties (Dietrich, 2005) ....................................... 42 

Table 4:  Data on soil fractions within 0-30 and 30-60 cm at burnt and unburnt sites ................. 47 

Table 5:  Data on soil physical properties within 0-30 and 30-60 cm at burnt and unburnt sites 49 

Table 6: Analysis of soil chemical properties within the depths of 0-30 and 30-60cm at both 

burnt and unburnt sites ................................................................................................... 52 

Table 7: Values of Pearson correlation between top soil parameters at burnt site; K = potassium, 

C= carbon, Na = sodium, Ca = calcium, OM = Organic matter, Mg = magnesium, EC = 

Electrical conductivity, TN = Total nitrogen and HC = Hydraulic conductivity .......... 54 

Table 8: Values of Pearson correlation between top soil parameters at unburnt site; K = 

potassium, C= carbon, Na = sodium, Ca = calcium, OM = Organic matter, Mg = 

magnesium, EC = Electrical conductivity, TN = Total nitrogen and HC = Hydraulic 

conductivity.................................................................................................................... 57 

Table 9: Land use and land cover of Central Gonja District ........................................................ 64 

Table 10: Socio-demographic characteristics of respondents ....................................................... 66 

Table 11: Effects of charcoal production on the environment ...................................................... 67 

Table 12: Nature of raw materials ................................................................................................ 68 

Table 13: Reasons for charcoal production .................................................................................. 69 

 

 

 

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LIST OF FIGURES 

Figure 1: Downward spiral of soil degradation due to vegetation loss ......................................... 20 

Figure 2: Land use and impact on vegetation change ................................................................... 24 

Figure 3: Map of Ghana showing the Districts in Northern Region ............................................. 28 

Figure 4: Map of Central Gonja District (CGD) showing research communities (Source: 

produced by Tetteh, Dept of Geography, UG, 2013) .......................................................... 33 

Figure 5: Soil sampling procedure ................................................................................................ 35 

Figure 6: (a) and (b): Correlations of soil parameters at Burnt and Unburnt sites ....................... 55 

Figure 7: (a) and (b): Correlations of soil parameters at Burnt and Unburnt sites ....................... 56 

Figure 8 (a) and (b): Correlations of soil parameters at Burnt and Unburnt sites ........................ 58 

Figure 9 (a) and (b): Correlations of soil parameters at Burnt and Unburnt sites ........................ 59 

Figure 10: Satellite images of vegetation dynamics of the study area in 1990. (Source: produced 

by Tetteh, Dept of Geography, UG, 2013) .......................................................................... 61 

Figure 11: Satellite images of vegetation dynamics of the study area in 2000. (Source: produced 

by Tetteh, Dept of Geography, UG, 2013 ............................................................................ 62 

Figure 12: Satellite images of vegetation dynamics of the study area in 2010. (Source: produced 

by Tetteh, Dept of Geography, UG, 2013) .......................................................................... 63 

Figure 13: Home towns of charcoal producers in Gonja Central District .................................... 67 

Figure 14 (a) and (b): Correlations of soil parameters at Burnt and Unburnt sites ...................... 72 

Figure 15 (a) and (b): Correlations of soil parameters at Burnt and Unburnt sites ...................... 72 

Figure 16: Charcoal bags ready for sale at Juku ........................................................................... 76 

 

 

 

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LIST OF ABBREVIATIONS 

AAS Atomic Absorption Spectrophotometer 

BSU Built Up Areas 

CBD         Convention on Biological Diversity 

CLHEE Candlelight for Health, Education and Environment 

CSW     Closed Savannah Woodland/Dense Cover 

CGDA Central Gonja District Assembly 

DHG     Dense Herbaceous Grass 

ELC Environmental Literacy Council 

EC Energy Commission 

EPA   Environmental Protection Agency 

FAO   Food and Agriculture Organisation 

FGD Focus Group Discussion 

GEMP Ghana Environmental Management Project 

GHC Grass Herbaceous Cover 

GIS Geographical Information System 

GPS    Global Position System 

IPCC   Intergovernmental Panel on Climate Change 

IWASH Integrated Water, Sanitation and Health 

LPG Liquefied Petroleum Gas 

NS Not Significant 

OSW Open Savannah Woodland 

RWA   Resource Watch Agency 

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SPSS Statistical Package for Social Sciences 

S.D Standard Deviation 

SD Significantly Different 

SWALIM Somalia Water and Land Information Management  

TM Thematic Mapper 

UN United Nations 

UNNICEF United Nation International Children and Education Fund 

UNU-LRT United Nations University-Land Restoration Training 

WB World Bank 

WBO Water Body 

                                                             

                                                              

                                                            

                                                                  

                                                        

 

 

 

 

 

 

 

 

 

 

 

 

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CHAPTER ONE 

INTRODUCTION 

1.1 Introduction 

The environment, which is considered generally as a free gift of nature, has undergone serious 

transformation in the hands of man. This to a large extent is due to man‟s efforts to satisfy 

himself which leads to environmental degradation such as deforestation. The exploitation of the 

environment through farming, fishing, mining, lumbering, fuelwood, as well as charcoal 

production have socio-economic, environmental and policy implications to countries, especially 

when they are not well regulated (Nyame and Danso, 2006). These activities exert both short and 

long term impacts on the environment Mason (2009).  Land degradation is one single mark of 

man‟s existence on earth since time immemorial, from simple tilling of the land with hoes and 

cutlasses, and hunting with bow and arrows to the present day sophisticated methods of 

exploiting the environment through ploughing, gaming, manufacturing, fishing, lumbering, and 

mining). Based on this, the human population has transformed the environment at different levels 

and at different places depending on available technology and policies (Kammen and Lew, 2005; 

Nyame and Blocher, 2010). 

 

One area that has seen a dramatic transformation across the world as a result of human activities 

is the world vegetation, from its natural state to transitional zones and in many cases totally 

transformed. Areas which were in the past seriously forested have  been converted into dry or 

desert lands and desert conditions keep on crippling into savannah areas and other vegetation 

zones. It is estimated that about 25% of the world‟s forest harvested for fuel is converted into 

charcoal for domestic and industrial purposes (FAO, 1987). The role of charcoal as a reliable 

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energy source for the operation of industries such as metal smelting, chemical processing and 

other local craft industries in the developing countries besides being the major source of energy 

for domestic heating and cooking is huge (Msuya et al., 2011; Agyemah et al. 2012).  

 

With high population growth in African countries including Ghana since independence, it is said 

that the energy requirement of these countries has doubled and in some cases tripled without the 

corresponding increase in alternative energy supply from the pre-independence fuelwood and 

charcoal use (Ikurekong et al., 2009; Kammen and Lew, 2005). As a result, the traditional energy 

source (fuelwood and charcoal) remains the most used (Malimbwi et al., 2004; World Bank, 

1992). Besides being the most widely used energy source, charcoal production in most parts of 

Africa provides the desired income for households especially during the lean season when 

farming turns to provide little or no income for the support of families (Agyemah et al., 2012; 

Anang et al., 2011). Charcoal production continues to gain ground among the rural population 

because of the readily market from within and outside the local areas (Anang et al., 2011).  

 

The use of charcoal as a source of energy by majority of people in Africa both in the rural and 

urban areas and elsewhere in the developing world has been attributed to its low cost, availability 

and the common knowledge of its use in most households compared to other energy sources like 

fossil fuel and Liquefied Petroleum Gas (LPG) (Mbilinyi et al., 2007). Although, there is an on-

going effort to correct the deficiencies of the oldest method of charcoal production (i.e. 

carbonization) through modern kiln systems, practically the earth mound (kiln) remains the most 

popular method. Its common knowledge of production and use further makes it irresistible to 

most charcoal producers despite the associated environmental problems, such as incidence of 

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bushfires, pollution, habitat destruction, and the poor conversion rate in most parts of the world 

(FAO, 1987).  

 

There is evidence to the effect that high temperatures through charcoal burning have had 

noticeable effects on soil characteristics and mineralogy especially at the kiln site (Kettering et 

al., 2000 as cited in Oguntunde et al., 2004). Msuya et al. (2011) identified forest depletion and 

air pollution as some of the obvious environmental impacts of charcoal production. Msuya et al. 

(2011) estimated the combined effects of charcoal production and use at about 49,700,000, 

9,830,000, 1,109,000 and 12,478,000 tons of carbon dioxide, Nitrogen oxide, Sulphur dioxide 

and Methane respectively in Tanzania. The impact of this on human health and the environment 

could be far reaching, including its contribution to the depletion of the ozone layer which many 

scientists have attributed to the global increase in diseases like catarrhs, skin cancers and the 

unpredictable weather patterns.  

 

Msuya et al. (2011) categorized energy types largely used by households in Tanzania into 

traditional, intermediate and modern, out of which charcoal is most preferred in both rural and 

urban areas because of its relatively cheap cost. On the other hand, charcoal production has been 

identified as the cause of an estimated annual loss of 109,500 ha of forest in Tanzania. This loss 

in forest cover has a long term effect on soil fertility, water resources as well as wildlife habitat 

(Msuya et al., 2011).  

 

In Somalia, commercial production of charcoal around the plateau areas where Acacia tress 

grows naturally resulted in the depletion of the Acacia woodland. This led to the country‟s 

parliament to pass a legislation against the exploitation of the Acacia trees for charcoal 

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production and the commercial export of charcoal between 1969 and 1991 before the collapsed 

of central government following the country‟s civil war (FAO-CLHEE, 2006) . During this 

period, commercial production of charcoal resumed in Somalia defeating the objective of the 

legislation and further compounding the land degradation situation in the country (FAO-CLHEE, 

2006). 

 

From a high forest cover of about 8.2 million ha in 1900, Ghana‟s high forest is estimated at 

about 1.8 million hectares in the early part of (2000) and out of this only about 40,000 ha is 

outside the country‟s reserves (Mason, 2009). According to Mason (2009), the current 

deforestation rate of 2% is far beyond the global rate of 0.2% and also higher than Africa‟s 

average rate of 0.8% estimated between 1990 and 2000. Apart from the deforestation of the 

country‟s high forest, the savannah zones of the country are also under the threat of 

desertification (EPA-Ghana, 2012). According to Fosu-Mensah et al. (2012), farmer‟s 

observation of impact of environmental changes such as climate change on crop yield is very 

high although adaptation is still a big challenge among them.  

 

The drivers of deforestation and desertification include activities of charcoal producers 

(Agyeman et al., 2012; Mason, 2009; Anang et al., 2004). In Ghana, it is estimated that about 

71% of the country‟s energy supply comes from fuelwood and charcoal, and over 90% of 

household energy across the country use fuelwood and charcoal (Mason, 2009; Anang et al., 

2011). Suddenly, there are incidences of charcoal producers encroaching into the few reserves 

dotted across the country as wood for charcoal production becomes scarce (Mason, 2009). The 

use of grasses and other forms of biomass as fuel when setting fire in kilns has exacerbated the 

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depletion of the land cover (Anang, et al., 2011).   Given the increasing level of charcoal 

production in Ghana, it‟s imperative to understand how it affects environmental resources 

especially soil, a resource upon which other elements of the environment are based. 

1.2 Statement of the research problem 

A significant number of Sub-Saharan African countries are bedevilled with environmental 

degradation such as desertification, deforestation and decreasing soil fertility. The causes of this 

land degradation, among others, include charcoal production. The impact of charcoal production 

on soil properties is critical since soil elements such as nitrogen and phosphorus have profound 

impact on maize yield (Fosu-Mensah, 2012). The results of low soil productivity due to these 

activities include widespread malnutrition especially among rural dwellers. Commercial charcoal 

burning is one of the major and emerging environmental problems in the Northern Region in 

particular and Ghana at large.  The activity is predominantly practised in the savannah 

woodlands to meet the demands of rural folks and city dwellers who entirely depend on charcoal 

as a source of energy for cooking and other domestic needs.  

 

In recent times, there is a growing belief that large scale charcoal production in the Northern 

Region is contributing to desertification which, to a large extent, impacts negatively on the 

vegetation cover and soil fertility of the area (Anang, et al., 2011). In 2005, Gonja traditional 

rulers under the leadership of the Yegbun-wura (the overlord of the Gonja traditional area) came 

out with a bye-law which prevented large scale production of charcoal in the traditional area 

including Central Gonja District. Despite the good intentions of the traditional rulers, trade in 

charcoal only stopped for a while and started again under their watch.  

 

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The failure of the District Assemblies, local systems and institutions in the Northern Region of 

Ghana to address the charcoal production problem could be attributed to a number of reasons 

such as lack of reliable information about the effects of charcoal production on soil 

characteristics and vegetation cover, the socio-economic benefits to households as well as the 

perceptions of local communities of the impacts of charcoal production. Studies of charcoal 

production have been conducted in the Upper West Region by Agyemah et al. (2012) and the 

southern sector by Oguntunde et al. (2008). Anang et al. (2012) studied the economic impacts of 

charcoal production, suggesting that the environmental impacts are still not clearly understood.  

 

In addition, most of the studies conducted on charcoal production did not involve remote 

sensing. According to Lillesand et al. (2007), remote sensing as a tool is useful for environmental 

management, because of its large area coverage and its ability to capture huge information on 

single or multiple platforms for easy comparison and analysis. In view of the potential socio-

economic and environmental impacts posed by commercial charcoal production, and the fact that 

there is limited reliable information about its impacts on soil characteristics and vegetation cover 

in the Northern Region of Ghana in general and the study area in particular, this study was 

conducted to provide requisite data as well as bridge the knowledge gap. 

1.3 Objectives of the study 

1.3.1 General objective 

The general objective of the study was to assess the impact of charcoal production on soil 

properties and vegetation cover in the Central Gonja District. 

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1.3.2 Specific objectives 

The specific objectives of this study were;  

1. To determine the impact of charcoal production on soil properties in the Central Gonja 

District. 

2. To assess land use and land cover change in the Central Gonja District from 1990 to 2010 

using satellite imagery.  

3. To assess charcoal producers‟ perception about the effects of charcoal production on both 

soil properties and vegetation in the Central Gonja District.  

1.3.3 Hypotheses 

This study was based on the following hypotheses: 

H1:  Charcoal production has no significant impact on soil properties especially around the 

kiln site where burning takes place. 

H1:   The land use of the study area has not resulted in significant land cover change of the 

vegetation of the area. 

H1:   Although, most people are into charcoal production as source of their livelihood, they 

do not perceive it as having a negative impact on the environment. 

 

 

 

 
 

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CHAPTER TWO 

LITERATURE REVIEW 

2.1 Introduction 

This chapter covers the relevant literature available in the area both published and unpublished 

which is reviewed based on the relevant sections such as method of charcoal production, 

environmental impacts of charcoal production (impact on air, soil and vegetation). It also covers, 

land use and cover change as well as the use of remote sensing and Geographical Information 

System (GIS) for change detection. While available literature on charcoal production cuts across 

a wide range of issues, this review will primarily focus on the environmental impact of charcoal 

production with special interest on its impact on soil properties and vegetation. 

 

2.2 Theoretical framework  

Like many other problems confronting human society today, the problem of environmental 

degradation has been explained in many theoretical works. From the days of Harman Daly, who 

condemned the unsustainable use of natural resources motivated by the traditional economic 

notion that natural resources are infinite Environmental Literacy Council (2007), various 

concepts have been developed some in opposing direction to explain what is likely to happen to 

our common heritage (the environment) if measures are not taken to protect it.  

 

One person who has painted an infamous picture of how the individual in society can work in 

his/her self-interest to the detriment of the larger society by degrading the environment was 

Garret Hardin. In his famous concept of “The Tragedy of the Commons”, Hardin explained that 

the use of the “Commons” unlike lands belonging to the individuals in the society, is opened to 

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unsustainable use due to human greed.  More theories have been put forward to explain how 

individual greed and endless desire expressed in the way natural resources are exploited can 

bring misery to the larger society through environmental degradation (Environmental Literacy 

Council, 2007).  

 

Hardin‟s “Tragedy of the Commons” has worn hearts especially when it comes to explaining 

how unregulated use of the world natural resources such as exploitation of natural wood for 

charcoal production have caused various forms of land degradation be it Europe, Asia, America 

or Africa, both in the past and present. He noted that, human beings by their nature would want 

to maximize their selfish interest by using more and more from the “commons” even though the 

impact of these actions would at long last haunt the larger society. 

 

The tragedy of the commons in simple terms is saying that the environment would be degraded if 

laws are not made to regulate its use.  Using common grazing pasture lands to illustrate his point, 

Garret Hardin said that the individuals acting on their own self-interest, will want to add to their 

stock, more animals and graze more which otherwise would have been avoided by this same 

individuals if they were grazing on their private pasture land. This in the long run will lead to the 

ultimate depletion of the shared limited resource, even though individuals know the obvious 

outcome of their greed and understand that it is not in anyone's long-term interest for this to 

happen.  

 

In modern Ghanaian society, the attitude of charcoal producers in the rural areas who harvest 

wood for their trade leading to the depletion of the natural forest and woodlands can be explained 

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http://en.wikipedia.org/wiki/Resource


10 
 

in the context of Hardin‟s concept of “The tragedy of the common”. The charcoal producer 

motivated by his/her individual greed continuous to cut down trees to burn charcoal degrading 

the soils and vegetation, knowing very well that their actions are detrimental to the lager society. 

 

 This theory provides bases for environmental regulation to protect the world most used but less 

protected commodity (vegetation) especially in Africa. Despite numerous conventions and 

treaties Africa countries, like Ghana, have signed into pledging to protect their environment from 

degradation, there is still a high rate of degradation going on in these countries.   

2.3 Importance of charcoal  

The importance of charcoal greatly lies in the numerous uses or application of charcoal since 

time immemorial, such as its application in gunpowder production, tool for artistic, treatment of 

diseases, medium of absorption and purification of liquid substances, domestic and industrial 

energy source among others. As one of the oldest means of energy, the importance of charcoal 

spans from its application from domestic to industrial use, especially in the developing World. In 

Ghana like most parts of Africa, charcoal is used as a means of providing energy needs for both 

rural and urban population (Anang et al., 2011 and Msuya et al., 2011). According to the Energy 

Commission (2010) charcoal and fuelwood constitute over 60% households energy supply in 

Ghana. 

 

FAO (2000) measured the importance of charcoal in terms of households use in the urban Sub 

Saharan Africa by putting it at 54 to 71% and estimated that over 1 million families in Sub 

Saharan Africa use charcoal as their main source of energy in the urban area alone. Many writers 

have also tried to put market value on charcoal production considering the number of people 

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engaged in the trade as a means of income for rural population that produce charcoal for sale. In 

2000, the market price of charcoal produced in Sub Saharan Africa was estimated at US $60 

million which FAO intimated that if the figures were translated into daily wages of US$1.50, that 

80% of it would have created about 144,000 permanent employment earning more than twice the 

estimated average daily earnings of the region at the time (FAO, 2000).  

 

While there is no much information on how much local and central government gets from 

collecting taxes from the charcoal trade in Ghana, Hibajene and Kalumiana (2003) listed four 

different types of tax levies (stumpage, conveyance, council and market fees) as taxes collected 

on charcoal in Zambia which forms a good tax component to the government.   

 

Charcoal is a key energy source for many households in the developing world. In Ghana for 

example, it fuels small-scale industries (FAO, 1987 and Hibajene and Kalumiana, 2003). 

According to Ghana Energy Commission (2010) over 600,000 light to medium scale industries 

such as blacksmithing, and chop bars are been fuelled by charcoal.  

 

2.4 Method of charcoal production 

Charcoal is the general term for a range of carbonized materials, with varying combustion and 

dark properties (Amanor et al., 2002, cited in Stephen, 2011). The production of charcoal 

involves a skilful control of heat in a process called pyrolysis which leads to chemical 

breakdown. The product of this process, is a porous black substance of the burnt wood or 

material which weighs just about a fifth of the wood it is made from and has the ability to 

generate heat much more efficient when used compared to the material it‟s made from (Hibajene 

and Kalumiana, 2003; Kamemen and Lew, 2005; Stephen, 2011).  

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Methods of charcoal production vary from Mobile Kiln commonly used in advanced world such 

as Great Britain to the use of traditional earth clamp in most parts of Africa including Ghana 

(FAO, 1987; World Bank, 1992; Anang et al., 2011). One common practice in all these cases 

however, is the effort at regulating air circulation in the process leading to controlled combustion 

and eventually resulting into carbonation as charcoal is produced (Hibajene and Kalumiana, 

2003). 

 

According to Food and Agriculture Organisation-Somalia Water and Land Information 

Management FAO-SWALIM (2009) charcoal production in Africa is largely practiced using 

traditional methods with the pit and the earth clamp being the most widely practiced. The process 

involves felling of trees and cutting of the wood into stacks which are loaded into a pit or on the 

ground (the earth-mound kiln) and covered with materials before being ignited with fire starting 

the process of controlled combustion (Hibajene and Kalumiana, 2003). Hibajene and Kalumiana 

(2003) established that charcoal production as practised in developing countries involve steps 

such as; gathering of wood and chopping of the wood into manageable pieces, packing/arranging 

the pieces of wood into prepared kiln, putting materials such as soil on the kiln to regulate air 

circulation, setting fire to the buried wood to start burning, managing kiln leading to charcoal 

production and finally, taking out the carbonated wood for sale. 

 

Charcoal burning as well as management of kiln benefits immensely from the expertise of the 

producer, access to the raw material and to a larger extent the number of people or workers that 

the producer has (Boutette and Karch, 1984, as cited by Hibajene and Kalumiana, 2003). 

Sustainable charcoal production requires that expertise of the charcoal producer is brought to 

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bear on the management of his/her source of raw materials such as the forest. According to 

Hibajene and Kalumiana (2003), from the very point of felling a tree for charcoal production, 

charcoal producers ensures that the trees are cut in a manner to sustain the forest.   

  

Materials for charcoal production are carefully selected to maximize yield. Apart from trees 

exempted from charcoal production for economic or religious beliefs the size and hardiness of a 

tress also influence the selection process (Pagama, 1993 as cited by Hibajene and Kalumiana, 

2003). In an extensive work on charcoal production in Zambia, Hibajene and Kalumiana, 2003, 

explained that knowledge of kiln management such as selection of materials for kiln construction 

is very critical. They concluded that soil used in building a wall around the charcoal kiln needs to 

be carefully selected so as to avoid cracks on the walls as the soil is exposed to heat. The 

assertion is further buttressed by FAO (1987) when it made the point that because vertisols 

contracts and develop fissures when exposed to heat, it should not be used as soil lump to 

construct kiln walls. Wood carbonation is a critical part of charcoal production. Efficient 

management of the carbonization process in charcoal production not only ensures quality 

charcoal been produced but it also leads to high yield per kiln site.  

  

2.5 Environmental impact of charcoal production 

Charcoal production is believed to have a significant impact on all natural resources used in the 

process especially the local vegetation and soil. In addition, burning of charcoal impacts on the 

surrounding air due to excessive smoke that emanates from the controlled carbonization 

(Chidumayo, 2011). The use of fire to generate the desired heat in kilns, and the clearing of 

forest and woodland resources also contribute to land degradation. These practices seem to 

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generate concerns about the impact of charcoal production in almost all the countries where 

commercial charcoal production takes place (Oguntunde et al., 2008; Hofstad et al., 2009).  

 

Tree felling forms the basis for charcoal production, although it varies from country to country 

and even sites within each country depending on the method used. The method used depends on 

how complex charcoal production has taken root, as different working tools or machines such as 

cutlasses, axes and in some cases chainsaws are used. Depending on the tools or machines used, 

tree cutting has left dramatic impact on vegetation and soil in communities where charcoal 

production has taken place (Anang et al., 2011; Chimayo, 2011; Msuya et al., 2011). In most 

cases, charcoal production results into land cover change. One area where charcoal production 

has triggered concerns largely has to do with its impact on vegetative cover which has a direct 

relation to loss of subsoil nutrients, siltation of surface water bodies, flooding, and water 

shortages due to its impact on hydrology, it also causes depletion of biological diversity such as 

reduced fauna and fora richness (Oguntunde et al., 2008).  

2.5.1 Impact on air quality 

The processes involved in charcoal production leads to emission of gases into the atmosphere 

which contributes to air pollution (Baillis 2009; Gomes and Encarnacao, 2012; Msuya et al., 

2011). Thus, apart from being one of the causes of land cover change in many communities 

where it is practised, commercial charcoal production is a major contributor to air pollution 

through emission of gases. 

 

According to Kammen and Lew (2005), emission of greenhouse gases into the atmosphere 

across the world‟s tropical ecosystems where charcoal production is prevalent is a major source 

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of greenhouse gas from most developing countries where industrialisation other sources of 

greenhouse gas emissions are minimal or non-existent compared to the developed world. 

Chidumayo and Gumbo (2013) noted that because of the nature of charcoal production in 

developing countries, emission of greenhouse gas from charcoal burning due to mismanagement 

makes charcoal production a major greenhouse gas source compared to bushfire. Table 1 shows 

the emission rates of greenhouse gas across the world.  

Table 1: Greenhouse gas emissions from charcoal production in tropical ecosystems of the world 

Region  Estimated charcoal 

production in 2009 

(million tons) 

Greenhouse gas emissions (million tons) 

Carbon 

dioxide 

Methane Methane (CO2 

equivalent) 

Total CO2 

Africa 26.116 46.70 0.84 20.93 67.63 

Asia 5.006 8.95 0.16 4.01 12.96 

Central America  1.061 1.90 0.03 0.85 2.75 

Oceania  0.012 0.02 0.00 0.01 0.03 

South America  7.621 13.62 0.24 6.10 19.72 

All regions  39.816 71.19 1.27 31.85 103.04 

Source: Kammen & Lew (2005) 

 

Methane, one of the major gasses emitted during charcoal production is considered short-lived 

in the atmosphere and has little or no impact on climate change according to the 

Intergovernmental Panel on Climate Change (IPCC, 2007). This however, seems not to be 

universally acceptable as many researchers including (Baillis, 2009 & Chidumayo, 2011) 

consider methane as greenhouse gas. Highlighting the contribution of charcoal production to 

greenhouse gas, Kammen and Lew (2005) concluded that emission during charcoal production 

is far more than what is emitted during charcoal use.   

2.5.2 Deforestation 

Charcoal production has been identified as one of the earliest major causes of deforestation in 

Europe especially in Britain during the Middle Ages (Armstrong, 1978, cited in Msuya et al., 

2011). The disappearance of natural forest in many parts of Britain such as the Sussex 

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Downs, the New Forest and the Forest of Dean is said to be as a result of forest wood being 

cut to produce charcoal to fuel the new iron industry (Boutette and Karch, 1984). This 

account has been widely corroborated by many writers investigating deforestation in Europe 

around the same period. Account of charcoal production in many parts of the world 

especially in developing countries such as Brazil, Tanzania, Senegal, Somalia, Ghana and 

many others today paints a gloomy picture of unsustainable use of forest and savannah 

woodland resources (Chidumayo, 2011; Mason, 2009; Msuya, 2011; Baillis, 2009).  

 

Deforestation is a major environmental problem associated with charcoal production across the 

world. According to Chidumayo and Gumbo (2013), estimates in 2009 put deforestation caused 

by charcoal production in various parts of the world at; Oceania 5.40 km
2
,
 
Central America 390 

km
2
,
 
South America 2400 km

2
,
 
Asia 5100 km

2
,
 
and Africa 29,760 km

2
. 

 
Africa appears to be 

leading when it comes to deforestation resulting from charcoal production with Tanzania being 

one of the heaviest hit as about 33.16% of its forest is depleted due to charcoal production. 

  

Determination of deforestation attributable to charcoal production in the midst of many other 

human activities with varying potential impacts on the environment is based on estimation 

(Hibajene and Kalumiana, 2003). Hibajene and Kalumiana (2003), however, estimated 

deforestation caused by charcoal production using the formula; 

 

Where; 

Dc is annual deforestation, in hectares, arising out of charcoal production,  

Wp is the quantity of wood, in tons, used to produce charcoal in a year, and  

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Sr is the stocking rate, in tons/ha, in this case the amount of usable wood for charcoal 

production.   

 

According to FAO (2000), population increase coupled with increasing demand for land-based 

resources accounts for almost all the deforestation and land degradation in Sub-Saharan Africa. 

FAO (2000), maintained that as a result of unsustainable use of charcoal and fuel wood in this 

region, fuelwood and charcoal consumption is likely to move from estimated 15.9 million m
3
 in 

1998 to 20.6 million m
3 
within ten years.  

 

Many including (Ribot, 1999 and Tappan et al., 2004) believe that the impact of charcoal 

production on forests especially in West Africa has not been fully told, emphasising that 

charcoal production has not only caused deforestation but also degradation in most places. 

Writing on charcoal production in Senegal (Tappan et al., 2004) revealed how the activities 

of charcoal producers led to degradation of the Tambacounda region in the late 1980‟s. 

Tappan et al. (2004) concluded that charcoal production not only degraded the region‟s 

woodlands but also altered the biodiversity composition of the area.  

 

In Ghana, the one-time cherished forest and savannah has since been declining as a result of 

human activities such as charcoal production.  According to Resource Watch Agenda (2010), 

Ghana‟s forest cover loss is estimated at about 75 percent of her 8.2 million hectares. FAO 

(2001), described energy demand and supply in most areas in Ghana as imbalanced leading to 

heavy reliance on the natural forest especially in the three northern regions. The UN agency, 

explained that this has led to serious clearing of the savannah woodlands for fuelwood and 

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charcoal production in the Brong Ahafo, Northern, Upper East and West regions of the country 

leaving the immediate surroundings of communities little or no vegetation.  

 

2.5.3 Biodiversity loss 

Concerns over biodiversity loss have been growing in the last few decades as more and more 

previously known species continue to reduce in numbers and in some cases disappeared entirely 

(Akingbogun et al., 2012). The human factor is by far considered as the most damaging because 

of the scale and the frequency it is taking place, as more and more areas are converted due to 

land use change destroying natural habitats (Akingbogun et al., 2012). According Akingbogun et 

al. (2012) biodiversity loss today is largely due to economic activities despite the numerous 

services human beings get from it. According to the Convention on Biological Diversity (1992), 

“Biological diversity means the variability among living organisms from all sources including, 

inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of 

which they are part; this includes diversity within species, between species and of ecosystems”.  

 

The raw material for charcoal production in most parts of the world is wood harvested from the 

natural forest (Chidumayo, 2011). Mason (2009) emphasised that the cutting down of trees for 

charcoal production has led to disappearance of certain tree species as well as wild animals and 

micro-organisms in both the forest and savannah ecological zones in Ghana. Kindt et al., (2008) 

observed that the impacts of wood harvest and charcoal production when situated in the context 

of ecological damage tree-cutting brings about becomes much more revealing. They indicated 

that where charcoal production is based on selective wood harvesting in most cases leads to 

changes in species composition as the most harvested species tend to disappear leaving the less 

preferred species. Kindt et al. (2008) made their conclusion based on the study they conducted 

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comparing national reserves and opened land and the species composition in Mali, Senegal and 

other countries in West Africa.  

 

2.5.4 Impact on soil 

Charcoal production involves tree-cutting which exposes the topsoil to other agents of erosion 

and at the same time it involves digging up the soil in the case of earth-based kilns for burying 

of wood which is then processed into charcoal (Hibajene and Kalumiana, 2003;Oguntunde et 

al., 2008). Oguntunde et al. (2008), in their study of the impact of charcoal production on soils 

in the forest zone of Ghana stated that the production of charcoal can impact on soil at both the 

kiln site as well as the surrounding area where wood is normally harvested.  

Studies of soil condition using parameters like exchangeable cations (Ca
2+

, Na
+
 and Mg

2+
), 

total nitrogen, and others in both charcoal burning sites and adjacent field sites have revealed a 

significant variation where soil properties are the same indicating that charcoal burning 

impacts on the soil especially at the kiln site (Oguntunde et al., 2008; Ogundele et al., 2012; 

Alexis et al., 2007). The relationship between vegetation cover and soil condition has long 

been established in most parts of the world. Whisenant (1999) diagrammatically illustrated the 

impact of vegetation loss emanating from land use and the impact on soil condition from short 

to long term. Below is a diagram from Whisenant showing the relationship between vegetation 

cover and soil condition. 

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                                             Source: Whisenant (1999) 

Figure 1: Downward spiral of soil degradation due to vegetation loss  

 

The above diagram illustrates impact of soil exposure due to vegetation loss in an area. It 

indicates how activities such as indiscriminate felling of trees for charcoal production will 

ultimately lead to reduction in vegetation cover and poor soil fertility without efforts at achieving 

sustainable land management. It shows that vegetation loss damages soil surface and that leads to 

acceleration of soil degradation by impacting of soil infiltration, soil fertility and in the long run, 

affects crop production. 

2.5.4.1 Soil fertility and soil erosion 

There is a correlation between deforestation and low agricultural productivity due to land 

degradation Whisenant (1999). The removal of vegetation through tree felling exposes the soil to 

run-off whenever it rains leading to the removal of the top soils which by far is known to contain 

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most of the soil nutrients and thereby causing low agricultural productivity (Mason, 2009). As a 

result of over reliance on nature for energy needs of most people in Sub Saharan Africa through 

fuelwood and charcoal production, the vegetation cover of most countries have  witnessed 

reduction over the years (Msuya et al., 2011).  Apart from impacting on soil fertility, charcoal 

production due to its nature is noted for causing reservoir siltation, flooding, water shortages due 

to shifting ground water regimes due to vegetation loss in local or production areas (Oguntunde 

et al., 2008; Chimayo, 2011; Mason, 2009).  

 

2.6 Geographical Information System (GIS) and Remote Sensing  

Remote sensing since its use in the 1940s has been defined severally by many authors, one 

unique feature in the definition of remote sensing which however cuts across these definitions is 

the issue of information acquisition without being in touch with whatever is being investigated 

within a spatial setting (Tappan and Cushing, 2008; Ramachandran, 1993; Lillesand et al., 1994), 

GIS on the other hand is a tool for data analysis including information from landforms to 

demographics. Information or data for GIS can be acquired from various sources such as public 

data bases, map, aerial photos, satellite scans, etc. 

 

The system uses electromagnetic radiation as a medium of communication between itself and the 

earth surface and as energy from the electromagnetic radiation is absorbed, transmitted, scattered 

and reflected based on the features of the object under investigation, the features of the objects 

are recorded as the “spectral signature” of the object which is useful for subsequent analysis 

(Lillesand et al., 2008). These features make the results of remote sensing suitable for the study 

and management of natural resources such as vegetation in modern day.  

 

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The ability to use GIS in decision making is made easier because of its geo-referencing 

capability which enhances data accuracy. GIS as a tool fills the enormous gap along the 

information chain as it is been used as a medium of storing information collected as well as 

serving as a good analytical tool for data processing. Many management decisions have be made 

in recent times based on information acquired from remote sensing and GIS technology 

especially when it comes to planning and natural resource management (Egeru et al., 2010; 

Rimal, 2005; Prenzel, 2003). 

 

Researchers have taken advantage of the unique features that remote sensing presents by 

adopting it as an approach for understanding land degradation problems among others, since 

understanding the processes and products of interaction in the environments is very complicated. 

A careful assessment of changes that occur in the environments and in various ecosystems forms 

a major milestone for effective ecosystem management and leads to sustainable utilization of 

forests as well as savannah resources.  

 

GIS works effectively based on reliable information which can be manipulated, this is achieved 

through scientific data. Remote sensing technology in recent years has been used to collect these 

data and proved to be reliable when it comes to acquiring data for effective resources 

management of any ecosystem (Ramachandran, 1993; Baillis, 2009). The use of GIS in 

analysing changes and trends that have occurred in different themes can influence the direction 

of policies and decision making at both local and national levels (Lillesand et al., 2008).  

 

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In their study of the changes in the woodlands of Tanzania between 1991 and 1998 taking into 

consideration both temporary and spatial factors in the eastern part of Tanzania, Mbilinyi et al. 

(2007) used remote sensing due to its synoptic nature, repetitive and uniform capability to 

facilitate the acquisition of information and for monitoring. Combined with GIS, the information 

acquired through remote sensing was easily extracted analysed taking advantage of both visual 

and digital image interpretation capability of this tool.  

 

2.7 Impact of charcoal production on land use and land cover change  

Land use and land cover are sometimes used as synonyms. According to Meyer and Turner II 

(1994), while land use looks at manipulation of land and land resouces or the purpose of a piece 

of land with the objective of getting something out of it, land cover on the other hand is 

concerned about what is on the surface of a piece of land, particularly the vegetation stand and 

may include, water and many others in most cases. Land use and land cover therefore, play 

different roles in understanding and managing land since different land uses could lead to 

varying land cover situation even if two pieces of land are influenced by the same conditions 

such as climate, vegetation as well as relief. Charcoal production is one land use situation that 

has an enomous impact on land cover (Msuya et al., 2011; Chidumayo, 2011; Alexis et al., 

2007).  The impact of charcoal production on land cover or vegetation cover is largerly due to 

the fact that vegetation mostly trees forms the main raw material for charcoal production and in 

many cases resulting in unsustainable use of trees.  

 

Deforestation is a major environmental problem associated with charcoal production across the 

world. Pellant et al. (2005) demonstrated that land use practices such as charcoal production can 

influence land condition or land cover change, from a reversible degraded land condition when 

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disturbance is minimal to a virtually transformed land condition (eg vegetation cover change) 

when disturbance increases. The original vegetation which in most case are more resistant can be 

replaced by less resistant vegetation due to new disturbances such as felling of trees for charcoal 

production. Below is a modified diagram from Pellant et al. (2005) demonstrating pathways for 

transition from guinea savannah vegetation to Sahel savannah vegetation and as the vegetation is 

degraded more, moves are towards desert conditions.  

  

From figure 2: the transitional period of vegetative classes in State A: communities B & C 

(Guinea grass) which is more resilient to State B: and subsequently State C: which are both less 

resilient and prone to desertification demonstrates pathways of vegetative transformation from 

resilient to less resilient one. 

 

pathways for transition from guinea savannah vegetation to Sahel savannah vegetation and as 

the vegetation is degraded more moves towards desert conditions.   

                        

 

                  

 

 

 

 

 

                        

 

Source: Modified version of Pellant et al. (2005) 

                        Figure 2: Land use and impact on vegetation change 

Land use and land cover change in the past according to Ramankutty et al., (2002), was due to 

increase in human numbers but   greed and technological development man in the last century 

became the most devastating factors well over just increase in population as the cause of land 

use and land cover change, because fewer people are now capable of depleting or change land 

surfaces with the aid of heavy machines (Lambin et al., 2001).  

State A: Reference state 

High quality and more resistant savannah 

vegetation (Guinea grass) 

 

Community D 

 

Transition 1 

 

avannah) 

 

State B: TranState C: Modified 

vegetation, less resistant and prone to 

desertification 

sition state  

Less resistant savannah vegetation due 

to tree cutting (Sahel savannah) 

 

  

 State C: Modified vegetation, less 

resistant and prone to desertification 

Community D 

 

Community A 

 

Community B  

 

mmunity D 

Community E Community C 

Community B  
Community pathways 

(rela 

 

State C: Modified 

vegetation, less 

resistant and prone to 

desertification 

vely reversible) 

Community F 

Community B  

 

Community A 

Transition 1 

 

Community 

E 

 

nsition 1 

Transition 2 

 

                      Source: Modified version of Pellant et al. (2005) 

Figure 2: Land use and impact on vegetation change 

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Land degradation in most parts of the world in the past according to Lambin et al. (2001), was 

largely due to increase in population.  He concluded that technological development by man in 

the last century, in addition to population increase have worsened the situation. With the help of 

heavy machines, fewer people are now capable of depleting or change land surfaces than the past 

(Lambin et al., 2001). 

 

 2.8 Perception of charcoal producers 

The human perception has been used as research tool for assessing the way people prefer to do 

certain things in a particular way and not the opposite. According to Little (1999) human 

perception can both be immediate which deals with the way people see their physical 

environment as well as one that comes in the form of informative (interpretative) perception. 

This perception has been identified as one of the many things that influence people 

understanding and the way people do things including how they treat their environment. 

Understanding individual or a group of people perception in a given area therefore plays a 

significant role when it comes to natural resource analysis and management (Little, 1999).  

                        

The way people act within their environment is therefore, said to be the outcome of their 

physical experience and the way they recognise things around them and their influence. Through 

the perceptual process, we gain information about properties and elements of the environment 

that are critical to our survival. Little (1999), maintained that among other things, our perception 

helps us to create picture of the world around us through our experience and enable humans to 

work within their environment. The immediate combined with the human psychology leads to 

interpretation which can be informative and this is useful when it comes to assessment of the 

way people act or do certain things. Therefore, charcoal producers were interviewed to 

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understand their perception about charcoal production and the impact on their environment since 

perception can influence people way of using the natural resources. 

 

 

 

 

 

 

 

 

 

 

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CHAPTER THREE 

METHODOLOGY 

This chapter outlines the techniques and procedures used in undertaking the study. The chapter 

therefore highlights the research design, data requirements and sources, data collection tools and 

methods, sampling techniques, study variables, and plan for data handling and processing data. 

 

3.1 The study area 

The Central Gonja District Assembly (CGDA) is one of the districts in the Northern Region of 

Ghana that were created in 2004. The district is an infant one but with vast human and natural 

resources. The district is located at the South Western part of the Northern Region of Ghana. The 

Central Gonja District Assembly (CGDA) lies within longitude 1˚5‟and 2˚ 58‟ West and latitude 

8˚32‟and 10˚2‟ North. The district shares boundaries with the Kintampo District of the Brong 

Ahafo Region to the South, the West Gonja District to the West, the Tamale Metropolis to the 

North, the Tolon-Kumbungu District to the North West, and the East Gonja District to the East. 

The district is strategically located because it links the Northern Region to the rest of the 

Southern part of Ghana. The District covers approximately 8,353 km² which represent 12% of 

the total land area of the Northern Region.  

 

 

 

 

 

 

           

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                   Source: Central Gonja District Assembly Document (2006)  

                      

 Figure 3: Map of Ghana showing the Districts in Northern Region 

 

3.1.1 Relief and drainage 

The topography is generally undulating with altitude of between 150-200 meters above sea level. 

The major rivers which drains the district are the White Volta and Black Volta which joins each 

other around Tuluwe and Mpaha. The confluence of the Black and White Volta Rivers is at Sheri 

which is a potential site for tourist attraction. Both the Black and White Volta haves good 

potential for small-scale irrigation schemes along their valleys. They also provide good 

waterways from Buipe and Yapei respectively to Akosombo via the Volta Lake in Yeji and have 

good potentials for fishing in the district. There is an inland harbour at Buipe on the Black Volta.  

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3.1.2 Climate  

The district experiences extreme temperatures from November to March during the year. The 

daily temperatures range from 24
0
C to 37

0
C in the course of the year. The mean monthly 

temperature is 27˚C, and humidity is very low causing dry skin and cracked lips of humans. The 

district experiences the North East Trade Winds popularly known as the Harmattan, winds from 

December to February which are characterised with cold nights and dry winds during day time. 

The climate of the area is also influenced by the south west monsoon winds which blow from the 

April to October and causes rainfall leading the two seasons (dry and wet seasons). The mean 

annual rainfall is about 1144 mm. The rainfall pattern is erratic, beginning in late April to late 

October. June, July and August generally record the highest rainfall and also the highest number 

of rainy days. The rainfall is characterized by thunder storms or heavy showers. Soil erosion and 

floods are common due to the torrential nature of rains. The irregular distribution and short 

duration of the rainfall are a great limitation to crops and vegetative growth.  

 

3.1.3 Soil and geology  

The district is situated in an old geological area. The rocks are mainly of the Voltaian formation 

with isolated Cambrian rocks which contain valuable minerals such as gold and diamond. 

Limestone occurs between the lower and middle Voltaian formation around Buipe, the capital of 

the district. The soils are generally made up of savannah ochrosols (oxisols, eutrustols, 

inceptisols) as well as groundwater laterites, from the voltaian rock formation. These variations 

are as a result of the drainage system in the area (Asiamah et al., 1996). Generally, the soils in 

the district are said to be fertile for agriculture purposes. 

 

 

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3.1.4 Vegetation  

The natural vegetation is guinea savannah dominated by Butyrospermum parkii (Shea), Parkia 

clappertonniana, (Dawadawa), Adansonia dititata (Baobab), Acacia sp. (Acacia), Azadirachta 

indica (Neem) and Khaya senegalensis (Ebony). These trees are scattered except in most valleys 

where isolated woodland or gallery forest are found. Most trees are deciduous, shedding their 

leaves during the dry season. Grass which grows in tussocks may reach 2.7 m during the rainy 

season. The original vegetation around settlements such as Buipe, Yapei, Mpaha and Kusawgu 

has been seriously impacted by human activities such as charcoal burning, fire wood harvesting, 

farming and also bush fires (Asiamah et al., 1996). One of the forest reserves in the district, the 

Yakumbo Forest Reserve located at the western part of the district capital is equally not spared 

these destructions.  

 

3.1.5 Demographic characteristics 

The district has about 69,665 people according to the 2000 population census but the recent 

population projection by the Ghana Statistical Service (2010) put the figure at 104,985. The 

population, though not evenly distributed according to the projection, has large concentration of 

people in a few large settlements such as Buipe (8,347), Yapei (4,044) and Mpaha (4,126). The 

population density of the district is 8.3 persons per sq. km which is below the regional density of 

25.9 persons per sq. km. The district population growth rate of 3.1% is higher than the national at 

2.8%. The sex ratio is 103 males to 100 females. The population is concentrated in a few 

accessible areas or settlements like Buipe, Yapei, and Mpaha. The age structure is typical of 

developing countries with over 50% between 15-60 years of age (Table 1).  

                              

    

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 Table 2: Age and sex structure 

Age groups Male (%) Female (%) Total (%) 

0 – 4 7.4 7.3 14.7 

5 - 9 7.2 7.5 14.7 

10 – 14 5.9 6.2 12.1 

15 – 19 4.8 2.9 7.7 

20 - 24 4.2 2.6 6.8 

25 - 29 4.4 3.6 8.0 

30 – 34 2.8 4.0 6.8 

35 – 39 3.4 5.1 8.5 

40 – 44 2.3 2.3 4.6 

45 – 49 2.0 1.9 3.9 

50 – 54 1.6 1.5 3.1 

55 – 59 0.9 1.0 1.9 

60 – 64 1.0 0.9 1.9 

65 + 2.8 2.5 5.3 

 50.7 49.3 100.0 

Source: 2008, United Nation International Children Education Fund/Integrated Water, Sanitation      and Health 

UNICEF/IWASH 

 

3.1.6 Economic activities 

The main economic activity of the people is agriculture involving crop production and livestock 

farming. The land is fertile for farming which is done extensively. Crops cultivated include 

maize, sorghum, millet, groundnut, cowpea, soy beans, yam, rice, and cassava. Other economic 

activities undertaken in the district are charcoal production, small- scale agro-based industries 

such as shea butter processing, rice milling, groundnut oil extraction and gari processing. Shea-

butter processing and charcoal production are some of the major commercial activities for 

Women. Fishing and livestock production are considered as supplementary activities to crop 

production. Large scale fishing is carried on at Yapei and Buipe on the White and Black Volta 

lakes. The major animals reared are cattle, sheep, goats, fowls, guinea fowls etc. The animals and 

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birds are practically reared in every home, but large scale ranching is non-existence in the 

district. 

3.2 Research design 

This study involved determination of some soil physico-chemical parameters, vegetation 

dynamics and a social survey. Therefore both experimental and cross-sectional designs were 

used. The latter involved focus group discussions and interviews of some community members. 

 

3.2.1 Selection of communities and respondents 

Selection of respondents for this study was guided by purposive sampling technique. The goal of 

purposive sampling is not to randomly select units from a population, but rather the main aim of 

purposive sampling is to focus on particular characteristics of a population that are of interest, 

which will best enable the researcher to answer research questions.  

 

Five communities where charcoal production is being carried out were selected for the study 

using purposive sampling (Figure 2). These communities were selected to correspond to the five 

local councils in the district. Each local council was represented by one community. The 

communities included; Juku in the Tuluwe local council, Jankura in the Yapei local council, 

Mankpam in Mpaha local council, Bouchipe in the Buipe local council, and Sankpala in the 

Kusawgu local council. Fifty charcoal producers were selected from each of the five (5) selected 

communities resulting in a total of 250 respondents. As part of the purposive sampling technique 

employed, charcoal producers in the research communities were identified during the pre-

interview visits and targeted for the face-to-face interview. The individual interview was focused 

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on the perception of charcoal producers about the environmental impacts of charcoal production 

in the area.  

 

Figure 4: Map of Central Gonja District (CGD) showing research communities (Source: produced by Tetteh, 

Dept of Geography, UG, 2013)  

 

3.3 Data collection            

Data was obtained from primary and secondary sources. Secondary data concerning the 

geography as well as the socio-economic activities of the Central Gonja District was obtained 

from the District Assembly, Geography Department and the University of Ghana libraries, 

journal articles, Forestry Commission and Environmental Protection Agency (EPA), while 

primary source included social survey and soil and land use/land cover analysis.  

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The social survey involved face-to-face interviews using interview guide to obtain information 

from charcoal producers as respondents in the selected five communities in the study area. Also, 

two focus group discussions were held at Juku and Sankpala to solicit detail information on 

charcoal production from the community members. The interview guide was first developed and 

pre-tested before actual administration was done in the field. 

 

3.3.1 Collection of soil samples 

To evaluate the impact of charcoal production on soil properties and vegetation cover, soil 

samples were taken at two (2) sites each in all the five communities from October, 2012 to 

January, 2013. Site selection was based on evidence of charcoal production within the last six 

months and unburnt site of 150 meters away from each site with demonstrable evidence of 

charcoal production serving as the control sites. This was done to ensure that samples have been 

taken from the same place, and the only factor for potential variation during samples analysis 

could be attributable to charcoal burning. In all, six composite samples were taken from each site 

(0-30 cm and 30-60 cm depths) three composite samples at each level. Sampling was done 

randomly from each of the areas within the burnt and unburnt sites. 

  

The soil samples were taken at two different levels from 0-30 cm and 30-60 cm at each sample 

point. At each site, three different triangles were constructed labelled T1, T2 and T3. In each 

triangle, samples were collected at the converging points of the lines (a, b and c; see figure 3), 

(Fosu-Mensah, Y. B., 2013, personal communication). The soil samples from each triangle from 

the same level were mixed and a composite sample taken leading to six composite samples of the 

two depths (0-30 cm and 30-60 cm) each for both the burnt and unburnt sites. The composite soil 

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samples were taken by driving a soil auger into the soil taken at the different depth and placed 

into sampling bag.  Samples were air-dried, ground and passed through a 2 mm sieve. The 

samples were kept in a polythene bag and labelled appropriately. Samples were taken to the 

Ecological Laboratory of the University of Ghana for physical and chemical analysis.   

 

 

            Source: Author’s construct 2013 

                         

          Figure 5: Soil sampling procedure 

 

3.4 Soil analysis 

3.4.1 Chemical analysis of soil 

The soil properties assessed were particle size distribution, pH, carbon, total nitrogen, Organic 

carbon, exchangeable cations: K
+
, Ca

2+
, Na

+
, Mg

2+
, electrical conductivity and hydraulic 

conductivity. These measurements were done for both burnt and unburnt soil samples. 

3.4.2 Determination of exchangeable potassium and sodium 

Flame photometry method was used to determine potassium (K
+
) and sodium (Na

+
) in the soil 

extract. To determine K
+
 and Na

+
, standard solution of 0, 2, 4, 6 8 and 10 ppm K and Na were 

a 

b 

a 

c 

b c 

b 

a 

c 

T1 

T2 

T3 

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prepared by diluting appropriate volumes of 100 ppm K
+
 and Na

+
 in volumetric flask using 

distilled water (see Moss, 1961).  

 

Ammonium acetate (1N NH4OAc) 77.08g of NH4OAc was dissolved into 800ml with water, 

then neutralised with concentrated NH4-H to pH 7.0. The solution was then diluted to 1 liter. In 

terms of extraction proceduce, 10g of soil was weighed into extractable bottle and 100ml of 1N 

NH4OAc solution added. This was placed in a bottle with content and then put in a shaking 

machine and shook for one hour. At the end of the shaking, the bottle was put in a centrifuge and 

centrifuged for about 20 minutes. The supernatant solution was finally filtered through No.42 

whatman filter paper. 

3.4.3 Determination of K
+
 and Na

+ 

An aliquot of the extract was then taken and sprayed into the flame as directed and obtain the 

photometer reading. The milliequivalents of the exchangeables K was then calculated by reading 

the flame photometer for the standard solution, as this was done and standard curve constructed, 

potassium and sodium concentrations in the soil extract were read from the standard curve.   

 The calculations were as follows:  

  

                                                         Spec reading 

Exchangeable K (cmol/kg soil)   = (3.1)  

                                                          Mw 39.1 

  

 

Where: W = weight of air – dried sample soil in grams  

   39.1 = mole of potassium  

   23 = mole of sodium 

 

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3.4.4 Determination of soil pH, electrical conductivity and hydraulic conductivity 

The pH and electrical conductivity of the soil were measured from reading (ratio 1:1) and (1:5 

soil: distilled water) respectively on standardised meters and finally the hydraulic conductivity 

was measured in the laboratory using the falling-head method (Klute and Dirksen, 1986). The 

advantage to the falling-head method in determining hydraulic conductivity is that it can be used 

for both fine-grained and coarse-grained soils. The soil sample is first saturated under a specific 

head condition. The water is then allowed to flow through the soil without maintaining a constant 

pressure head. 

3.4.5 Determination of exchangeable calcium and magnesium 

To determine exchangeable Ca
2+

 and Mg
2+

, 10 ml of the extract described in 3.4.3 for potassium 

and sodium determination was transferred to an Erlenmeyer flask and 5 ml of an ammonium 

chloride-ammonium hydroxide buffer solution was added followed by addition of 1 ml 

triethanolamine. A few drops of potassium cyanide and Eriochrome Black T solutions were then 

added. The mixture was then titrated with 0.02 M EDTA solution from a red to a blue end point.   

3.4.6 Determination of soil carbon and organic matter content 

To analyse the carbon and organic matter content of the soils, this was done by reducing the 

Cr207
2-

 ions by organic matter in which case the unreduced Cr207
2-

 is measured by titration. 

Organic forms of soil –C plus the carbonate forms of the element including HCO3- and CO3
2-

of 

any soluble salts present, constitute the total-C present in soils. Values for the organic-C content 

of soils may be expressed as such or may be reported as total organic matter by multiplying the 

figure for organic-C by the conventional “Von Bemmlen” factor of 1.724. Finally, the organic 

matter was calculated by multiplying the percentage C by the factor 1.724 to convert to organic 

matter (Black, 1965; Wakley and Black, 1934), 

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Potassium dichromate (K2Cr202) was dissolved in 49.04g of reagent grade K2Cr202 (dried at 105
0
 

C) in water and the solution diluted to the volume of 1000ml, then sulpuric acid (H2S04) 

concentrated (not less than 69%). If the CI
-
 is present in the soil, 1.25g Ag2SO4 would be added 

to every 100ml of the concentrate. H2S04 was employed as Orthophosphoric acid (H3PO4): 85%. 

At ferrous ammonium sulphate of (0.2N), 78.44g Fe (NH4)2(SO4)2 was dissolved in 500ml of 

water. With the addition of 20ml conc. and H2SO4 to get 1 litre barium diphnylamine sulphonate: 

0.16% aqueous solution. 

 

In terms of procedure, a representative sample of approximately 0.5g of soil was screened 

through 0.5mm sieve into a 250 Erlenmeyer flask. Then from a burette, exactly 10ml of 

dichromate solution was introduced followed by 20ml of concentration H2S04. The flask was 

swirled keeping the solution in contact with all the particles of compost or soil. The flask and 

content was allowed to stand on an asbestos sheet for 30 minutes, after which 200ml of distilled 

water, 10ml of orthophosphoric acid and finally 2ml of barium diphenyamine sulphonate 

indicator were added. This was then titrated with the ferrous ammonium sulphate solution until 

the colour changes to blue then to a green end-point. 

3.4.7 Calculation of percentage carbon (% C) 

The following formula was used (reference/source?); 

 

% carbon = [10.0-(X N) X 0.3] 

 

where X = ml of ferrous ammonium sulphate solution required for the titration 

N = normally of ferrous ammonium sulphate solution and 

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W = weight of soil sample in gram. 

 

3.4.8 Calculation of percent organic matter 

The percentage of organic matter in soil samples was calculated by multiplying the percentage C 

by the factor 1.724 to convert to organic matter (Bremner and Mulvaney, 1982).  

3.4.9 Determination of soil total nitrogen 

Soil total nitrogen was determined using the micro Kjeldahl distillation and titration method 

(Bremner and Mulvaney, 1982). The modified Kjeldahl method permits the total nitrogen to be 

precisely determined in plants and in soil. 

 

 A 1 g soil sample was weighed into a digestion flask, 5 ml concentrated sulphuric acid and few 

drops of 30 % hydrogen peroxide were added with selenium to serve as catalyst. The entire 

content was then digested. The use of this method converts organic nitrogen to ammonium 

sulphate and the resultant solution made alkaline by the addition of 5 ml of 40 % sodium 

hydroxide and ammonia distilled into 2 % boric acid and titrated with standard hydrochloric 

acid. The digestion of organic converted organic nitrogen to NH2
+
-N (ammonium nitrogen), this 

was distillated to release NH3 into an absorbing medium and volumetric analysis of NH3 formed 

during digestion process. 

Concentrated sulphuric acid (H2SO4), digestion accelerator: mixed together 10g NaSO4, 1g 

CuSO4.5H20 and 0.1g selenium, Sodium hydroxides, 40% NaOH. Mixed indicator: 0.13g of 

methyl red + 0.066g of methylene blue dissolved in 100ml of 95% of ethanol. Hydrochloric acid 

0.01m and boric acid (2%): 2g of H3BO3 in 100ml of distilled water. 

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In terms of procedure, a 1g of fine (2mm) composit soil was weighed into  a 500ml Kjeldahl 

flask A 4ml of distilled water was added to the soil thoroughly. A scoop of digestion accelerator 

mixture was added to each tubeafter which 5ml of concentrate H2SO4  was added. The mixture 

was digested by heating in fume cupboard gently at first until vigorously effervescence subside. 

The heating (boiling) continued for 1 hour after the digest was turned white with no charried 

organic matter remaining. The digest was cooled and 20ml with distilled water and allowed the 

sand or compost to particles to settle, and decanted the supernatant solution into a 50ml 

volumetric flask. The process was repeated by washing the sand or compost particles and 

quantitatively transfering all the ammonium to the flask, this was done up to the mark. 

 

An aliquot of 5ml was taken into a markham distillation apparatus, also, 5ml of the 40% NaOH 

and 100ml of distilled water were added. The mixture was distilled, collecting the distillate in 

5ml of the 2% boric acid-indicator mixture.The distillate was subsequently titrated with 0.01m 

HCI from green to reddish end point and the titre value recorded.   

3.5 Soil physical properties 

Soil physically consists of three main components namely sand, silt and clay. The process of 

separating a soil into its particles, and then estimating the proportion of particles in the various 

size ranges, is usually referred to as Mechanical Analysis or Particle Size Analysis (Bouyoucos, 

1962; Dietrich, 2005). 

There are several methods of particle size analysis, but only two have wide acceptance 

Bouyoucos (1962): i) The Pipette Method and ii) The Bouyoucos Hydrometer Meter Method. 

The Hydrometer method was used in this study. This method quantitatively determines the 

physical proportions of the soil particles as determined by their settling rates in an aqueous 

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solution using a hydrometer. The hydrometer method of estimating particle size analysis of sand, 

silt and clay content is based on the dispersion of soil aggregates using sodium 

hexametaphosphate solution and subsequent measurement based on changes in suspension 

density (see Dietrich, 2005).  

 

Reagent, sodium hexametaphosphate, Na(PO3)6 (611.78) 99%, Sodium carbonate, 

Na2CO3(105.99)99.9% and deionised water. Preparation of calgon, in 1 litre flask, 35.7g of 

sodium hexametaphosphate was dissolved in 750ml of deionised water. Then 7.49g of sodium 

carbonate was added and made up to 1 litre with deionised water. This was vigorous shaken to 

dissolve the hexametaphosphate. 

 

For the procedure, a 51g of air-dried soil (˂2mm) was weighed and transfer into a 250ml beaker, 

the results was dispensed with 50ml of the calgon solution and 100ml of deionised water to the 

soil. The suspension was stirred vigorously for 1 minute using a glass rod and made to stand for 

30 minutes. After that, the substance was transferred into the mixer and mixed for 15 minutes at 

a medium speed. After mixing, the suspension was transferred the into the sedimentation 

cylinder and made up to 1 litre with deionised water. 

 

In terms of measurement, the suspension was mixed in the cylinder by several vertical 

movements of the plunger (1-2min), the cylinder was then placed on a flat surface and the time 

noted. The soil hydrometer was immediately placed into the suspension, sliding the hydrometer 

slowly into the suspension until it started floating. The first reading was taken on the hydrometer 

at 40 seconds after the cylinder was set on (H1). The hydrometer was then removed and the 

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temperature of the suspension measured with a the