| Content | CHAPTER ONE
INTRODUCTION
1.1 Background to the Study
Soil is an important resource covering the land surface. Mining is the process of getting minerals and soil components for various uses. Man depends on soil for agriculture, construction and even as a habitat for various organisms (Mwangi, 2007). People benefit from soil particularly sand and gravel but interfere and disturb the resource through excessive exploitation to fulfill their needs. There is worldwide concern about the environment which prompted the researcher to carry out this study on the environment. It seems there is excessive mining of soil components for construction in both rural and urban development. Gravel is mixed with river sand in filling and compacting foundations, river sand is a component of concrete in making slab while pit sand is required for plastering buildings. River sand is used in most mixtures because it is a strong resource which strengthens even pit sand in plastering and makes durable bricks (Morwaeng, 2013).
Sand is a valuable resource and main input in the construction industry in many parts of the world (Eiskine and Green, 2000, Gob, et al, 2005). Mining excavation involves the removal of sand from their natural configuration. Sand mining occurs both on small and large-scale in major parts of Nigeria. It has been observed that with an estimated 16 million housing deficit (Ezekiel 2010; lsah, 2011) and infrastructural development in Nigeria, there will continue to be the great demand for sand and other construction materials (Omolu and Ajakaiye, 1988). Sand mining is a practice that is used to extract sand, mainly through an open pit. Sand is also mined from beaches, inland dunes and dredged from ocean beds and river beds.
Sand is often used in manufacturing as an abrasive, for example, and it is used to make concrete. It is also used in cold regions to put on the roads by municipal trucks to help during heavy rainfall and extreme weather conditions, usually mixed with salt or another mixture to lower the freezing temperature of the road surface (have the precipitations freeze at a lower temperature). Sand dredged from the mouths of rivers can also be used to replace eroded coastline (Kadi, et al., 2012).
The increasing rate of urbanization across the globe has brought with it several challenges ranging from physical, economic, social, to environmental among other issues (Cohen, 2006; Chelala, 2010: Kadi, et al., 2012). To cater for the rapid urbanization, several sites are now being exploited for the excavation of sand. Traditionally, sites for sand mining are rivers and beaches; however, sand is mined from river months, banks and even at inland sand deposits.
Rapid urbanization is a major cause for the demand of sand mainly used for building construction and is responsible for unsustainable extraction of sand from the many illegal inland sand, mining pit, sand mining operators, citizens, and government becomes more confrontational as a result of more sand excavation sites located in urban and rural areas. Conflicts have centered on environmental and social issues such as noise, truck traffic, dust, stream water quality, reclamation, biodegradation, population and visually unpleasant landscapes (Willis and Garrod, 1999), and the citizens concern on the adequacy of regulatory efforts of the government to control these negative effects.
Environmental impacts of mining are well documented in the form of waste management, impacts of biodiversity and habitat, deforestation of land with the consequent elimination of the vegetation, pollution (water, air, land and even noise pollution, etc. (Abdus-Saleque, 2008). In Nigeria and many other tropical areas sand mining is a major cause of deforestation and forest degeneration, generating a large number of environmental impacts (World Rainforest Movement, 2004). It is noted that large-scale mining activities generally continue to reduce the vegetation of most of the mining communities to levels that are destructive to biological diversity (Akabzaa, 2000). Davis and Tilton (2005) also suggest that local communities tend to bear the negative impacts of mining be it social, economical or environmental. It is therefore important to make effort to stem these problems through informed decision-making. However, making informed decision in many areas including monitoring sand mining activities often involves complicated processes for optimal decision making, information from various sources is required such as spatial information, which is essential to address activities of sand mining and their impacts on the environment (Burrough and McDonnell, 2O02).
1.2 Statement of the Problem
Abraka and Eku are both a growing urban centers which have experienced rapid population growth and physical expansion especially since the early 1990s with the establishment of the Delta State University which is situated at Abraka main town. This has resulted to the influx of people from different parts of the state. These in turn have exerted pressure on the needs for housing provision, in addition to construction of roads (Akinbode and Ugbomeh, 2006).
Sand mining is a direct cause of erosion, and also impacts the local wildlife. For example, sea turtles depend on sandy beaches for their nesting, and sand mining has led to the near extinction of gharials (a species of crocodiles) in Nigeria. Disturbance of underwater and coastal sand causes turbidity in the water, which is harmful for such organisms as corals that need sunlight. It also destroys fisheries, causing problems for people who rely on fishing for their livelihoods. Removal of physical coastal barriers such as dunes leads to flooding of beachside communities, and the destruction of picturesque beaches causes tourism to dissipate. Sand mining is regulated by law in many places, but is still often done illegally (Kadi, et al., 2012).
Abraka and Eku are expanding at an alarming rate. Expansion means growth in infrastructure, construction of new roads, commercial malls and residential areas (Wokorach, 2002). There is need for use of various soil components such as pit sand, river sand and gravel from various sites surrounding the city. People seem to be extracting these soil components excessively without considering the impact on the environment. Most likely, there is overexploitation of soil leaving deep pits on bare ground while rivers are widening daily. Soil mining has become a daily sight with tipper trucks carrying pit sand, river sand and gravel from rivers and open fields. It seems there are no strict rules to govern soil extraction. Deep and wide pits are left when pit sand and gravel are collected, riverbeds widen and deepen after removing river sand, affecting aquatic while gravel removal destroy ecosystems, forests and agricultural land (Mbaiwa, 2008). Pit sand organisms is collected from River Ethiope, river sand is from Ovwuvwe river while gravel is extracted from River Ethiope. There seemed to be a problem of environmental alteration, ecosystem and agricultural land destruction as well as riverbed and bank degradation due to excessive removal of pit sand, river sand and gravel which prompted the researcher to investigate the depth of these environmental impacts.
Sand and gravel were continuously excavated along the beaches and valley of river Ethiope from Urhuoka to Ajalomi even up to the axis of the boundary between Abraka and Eku of the River Ethiope. Dredging equipments are seen mounted along the course of the river that excavated the sand into piles along the River Bank. Daily tonnes of sand are carried into the town with trucks loaded. Contractors who cannot afford dredging machine uses locally made canoes and shovels to scoop large amount of sand along the beds and banks of the River. The impact of this excavation apart from acting as a source of income to the residents, are usually very negative.
The major problems associated with sand excavation and mining activities in Abraka-Eku region along River Ethiope include wrong channelization of the river channel, destruction of the riparian vegetation, degradation of the natural environment, impact on biodiversity, pollution of water, deforestation, erosion along the valley side slopes and disturbance of underground water and coastal sand causing turbidity in the water, which is harmful to organisms. Sand excavation causes degradation and severe effects on fish, causing problems for people who rely on fishing for their livelihoods. Sand excavation causes removal of physical coastal barriers such as dunes thereby leading to flooding of beachside, buildings, and disrupts tourism activities in the beaches. It is against this background that this study is conducted to investigate these problems and find possible ways to address the problems.
1.3 Aim and Objectives of the Study
The aim of this study is to assess the effects of sand excavation on the environment of Abraka-Eku along Ethiope River. In order to achieve the above stated aim, the following specific objectives were considered;
To identify the various sand mining/excavation sites along River Ethiope in Abraka and Eku.
To investigate the effects of sand excavation on coastal areas where excavation is done in Abraka-Eku region along the River Ethiope.
To proffer solutions to the sustainability of the environment where sand excavation is going on in the area studied.
1.4 Research Hypotheses
The following hypotheses guided the study;
Sand excavation has no significant impact on the environment of Abraka-Eku along River Ethiope.
Sand excavation has no significant impact on the coastal areas of the River Ethiope where excavation is done.
1.5 Study area
The study area (Abraka and Eku) is located in Ethiope East cal Government Area of Delta and in the Niger Delta Region of Nigeria.
1.5.1 Location and Size
River Ethiope which cuts across the two study areas (Abraka and Eku) took its source from Umuaja in Ukwuani L.G.A Delta State. River Ethiope is located in the South-South geo-political zone of Southern Nigeria. Abraka is located geographically at latitudes 050 451 to 050 501 North of the equator and longitudes 060 001 to 060 151 East of the Greenwich Meridian. Abraka is situated at the Eastern Bank of River Ethiope in Ethiope East Local Government Area of Delta State in the Niger Delta region of Southern Nigeria. It is bounded to the North by Orhionwon Local Government Area of Edo State, and to the East and in the South and West by Ukwani Local Government Area and the Ughelli North Local Government Area respectively. Abraka has a total area of landmass of 168,43square kilometer.
Eku is located geographically at latitudes 050 451 to 050 051 North of the equator and longitudes 060 061 to 060 161 East of the Greenwich Meridian. Eku is bounded in the North by River Ethiope, in west by Okpara-waterside, in the east by Abraka and in the South by Samagidi (both in Ethiope East L.G.A of Delta State). Eku has a total landmass of 65,8km2. The entire Ethiope East region falls under Agbon and Abraka clan which is part of the Urhoboland. | CHAPTER ONE
INTRODUCTION
1.1 Background of the Study
This study focuses on the environmental impacts of flooding on agricultural activities in Kwale and its environs. Flooding has been a long-term issue which affects the inhabitants of Kwale. In many natural systems, floods play an important role in maintaining key ecosystem functions and biodiversity. They link the river with the land surrounding it, recharge groundwater systems, fill wetlands, increase the connectivity between aquatic habitats, and move both sediment and nutrients around the landscape, and into the marine environment (Apan, et al., 2010). For many species, floods trigger breeding events, migration, and dispersal. These natural systems are resilient to the effects of all but the largest floods. The environmental benefits of flooding can also help the economy through things such as increased fish production, recharge of groundwater resources, and maintenance of recreational environments (Bunn and Arthington, 2002).
The environmental resources in Kwale most especially the land and soil resources are greatly threaten by flooding. The Kwale and its environ is covered by beautiful vegetation naturally checking the menace. This flooding menace has destroyed arable land for agricultural purposes which are the major socio-economic activities of the Kwale people. The government in his attempt to curb the situation has constructed a drainage system some meters away from the major road to redirect and channel all the water flowing to the erosion sites into the drainage system which is emptied into the river. Despite all this effort, the situation still remains the same.
Areas that have been highly modified by human activity tend to suffer more deleterious effects from flooding. Floods tend to further degrade already degraded systems. Removal of vegetation in and around rivers, increased channel size, dams, levee bank and catchment clearing all work to degrade the hill-slopes, rivers and floodplains, and increase the erosion and transfer of both sediment and nutrients (Douglas, et al., 2005). While cycling of sediments and nutrients is essential to a healthy system, too much sediment and nutrient entering a waterway has negative impacts on downstream water quality. Other negative effects include loss of habitat, dispersal of weed species, the release of pollutants, lower fish production, loss of wetlands function, and loss of recreational areas (Kingsford, 2000).
Flooding is one of the environmental problems that have confronted man since immemorial. Flooding is a widespread and age long phenomenon. In Kwale, flooding has created and causes untold hardship such as destruction of building and properties, interruption of socio-economic development of the area. Jon (2011), defined flooding as a condition, which exist when any overland flow over an urban or rural area, that is sufficient to cause property damage, health hazard, nuisance and the obstruction of the socio-economic activities in the area. He went further the types of flooding to include rivers flood, flash flood, splash flood and flood bondages.
Agriculture has changed significantly in terms of the production patterns and structure and a significant trend has been the development towards fewer and larger holdings with more intensified and specialized production. This development has included an increased mechanization and use of fertilizers and pesticides. Biodiversity has been affected negatively both by the physical changes in the landscape and by the changes in the production methods. As the agricultural production has intensified, all levels of biological diversity (genetic, species, and
habitats) have declined in farming environments. The more intensive land use corresponds for example to the decrease in the populations of farmland birds.
Many of our coastal resources, including fish and other forms of marine production, are dependent on the nutrients supplied from the land during floods. The negative effects of floodwaters on coastal marine environments are mainly due to the introduction of excess sediment and nutrients, and pollutants such as chemicals, heavy metals and debris. These can degrade aquatic habitats, lower water quality, reduce coastal production, and contaminate coastal food resources (Poff, et al., 2003). It is against this background that this study is carried out to examine the environmental impacts of flooding on agricultural activities in Kwale and its environs.
1.2 Statement of Problem
Flooding in key agricultural production areas can lead to widespread damage to crops and fencing and loss of livestock. Crop losses through rain damage, waterlogged soils, and delays in harvesting are further intensified by transport problems due to flooded roads and damaged infrastructure. The flow-on effects of reduced agricultural production can often impact well outside the production area as food prices increase due to shortages in supply (Prosser, et al., 2001). On the other hand, flood events can result in long-term benefits to agricultural production by recharging water resource storages, especially in drier, inland areas, and by rejuvenating soil fertility by silt deposition (Apan, et al., 2010).
Damage to public infrastructure affects a far greater proportion of the population than those whose homes or businesses are directly inundated by the flood. In particular, flood damage to roads, rail networks and key transport hubs, such as shipping ports, can have significant impacts on regional and national economies. Short-term downturns in regional tourism are often experienced after a flooding event. While the impact on tourism infrastructure and the time needed to return to full operating capacity may be minimal, images of flood affected areas often lead to cancellations in bookings and a significant reduction in tourist numbers (Apan, et al., 2010).
Flooding of urban areas can result in significant damage to private property, including homes and businesses. Losses occur due to damage to both the structure and contents of buildings. Insurance of the structure and its contents against flooding can reduce the impacts of floods on individuals or companies. As most people are well aware, the immediate impacts of flooding include loss of human life, damage to property, destruction of crops, loss of livestock, and deterioration of health conditions owing to waterborne diseases. As communication links and infrastructure such as power plants, roads and bridges are damaged and disrupted, some economic activities may come to a standstill, people are forced to leave their homes and normal life is disrupted (Kingsford, 2000).
Similarly, disruption to industry can lead to loss of livelihoods. Damage to infrastructure also causes long-term impacts, such as disruptions to supplies of clean water, wastewater treatment, electricity, transport, communication, education and health care. Loss of livelihoods, reduction in purchasing power and loss of land value in the floodplains can leave communities economically vulnerable. Floods can also traumatise victims and their families for long periods of time. The loss of loved ones has deep impacts, especially on children (Bunn and Arthington, 2002). Displacement from one's home, loss of property and disruption to business and social affairs can cause continuing stress. For some people the psychological impacts can be long lasting. Floods impact on both individuals and communities, and have social, economic, and environmental consequences. The consequences of floods, both negative and positive, vary greatly depending on the location and extent of flooding, and the vulnerability and value of the natural and constructed environments they affect (Douglas, et al., 2005). This study “environmental impacts of flooding on agricultural activities in Kwale and its environs” is therefore carried out to address the aforementioned problems.
1.3 Aim of the Study
The main of this study is to examine the environmental impacts of flooding on agricultural activities in Kwale and its environs. The specific objectives of this study includes:
To examine the environmental impacts of flooding on agricultural activities in the study area;
To identify the causes of flooding in the area;
To examine the consequent effect of flooding on agricultural activities in the study area;
To identify the various types of farm practices and agricultural productivity in the study area;
To identify the problems of flooding and areas seriously affected by flooding in the study area; and
To suggest mitigation measures to control the problems of flooding in Kwale and its environs.
1.4 Research Questions
The following question(s) raised by the researcher will be answered in this study;
What are the environmental impacts of flooding on agricultural activities in the study area?
What are the causes of flooding in the area?
What are the consequent effects of flooding on agricultural activities in the study area?
What are the various types of farm practices and agricultural productivity in the study area?
What are the problems of flooding and areas seriously affected by flooding in the study area?
What do you think are the mitigation measures to control the problems of flooding in Kwale and its environs?
1.5 Research Hypothesis
The following hypothesis stated in the null and alternative form will be tested in this study;
There is no significant relationship between the environmental impacts of flooding and the various types of farm practices/agricultural productivity in Kwale and its environs.
Crop yield is not significantly dependent on flooding and heavy rainfall in Kwale.
Occurrence of flooding in Kwale is not significantly depended on heavy rainfall, lack of drainage system.
1.6 Significance of the Study
This study will cover the whole of Kwale and its environs and its to look at the environmental impacts of flooding on agricultural activities in Kwale and its environs. It would also offer suggestion (s) on the causes of flooding and its effect on agricultural activities in the study area.
Therefore, the study will help to unfold the deteriorating effects of flooding on agricultural activities in Kwale and its environs and other related land use in Kwale, and also to look at the various cause (s) of flooding and the areas mostly affected by flooding in the study area and also to look at or proffer solution (s) to combat flooding problem (s) on agricultural activities and socio-economic life of the people in the study area.
1.7 Study area
The study area (Kwale) is located in Ndokwa West Local Government Area of Delta State and it’s the administrative headquarters of Ndokwa West L.G.A of Delta State.
1.7.1 Location and Size
Kwale is located between latitude 60 09N and 60 29N of the equator and longitude 50301E and 60031E of the Green Witch meridian. Kwale is a town in Ndokwa West Local Government Area of Delta in southern Nigeria. As a matter of fact, it is the headquarter of Ndokwa West Local Government Area which occupies an area of 816km2. Like any other community, Kwale is divided into six (6) quarters as follows: Umusederi, Isumpe, Umusam, Umusadege, Umuseti and Ogbe-ani. Majority of the population of Kwale are affected by water pollution due to presence of oil companies in the area such as Agip Petroleum Company, Sterling Global Company etc. and the people are prompt to different kinds of diseases. The area also experience destruction of fishes, plants animal life. | ABSTRACTS
The study area is located within latitude 050 271 4611N and longitude 0080 431 46E, and the elevation of the place is 156m. The major rock types encountered in the area include gneisses, quartzite, amphibolites and marbles. These are intruded by pegmatite, quartz vein and aplite. The latest metamorphic episode occurred during the Pan-African Orogeny (600 ± 15ma) and the deformation left a structural trend of NS and NE-SW on the rocks. The occurrence of NW-SE structural trend are also shown on some rocks indicating that the Pan-African event did not completely alter earlier structural imprints. The study area is highly forested, undulating in slope and is a characteristic of a tropical rain forest in the area.
Chapter One: Introduction
The geology of southern Akor and its environs lies within the Oban Massif, a component of the crystalline basement of Nigeria. The Nigeria crystalline basement in turn forms a part of the African crystalline basement and covers over 50% of the total land surface of Nigeria . The rock assemblages encountered and identified consists of mainly schists, gneisses, Amphibolite, Charnockite, Marble and Quartzites and pegmatite, Quartz vein and Aplite emerging as Igneous intrusive rocks. The area mapped and studied (Akor) is predominated by intrusive rocks and these rocks are very well exposed where the topographyis slopy along streams and river channels.
Ekwueme et al (1992) proposed that charnockite rock's occur in both the eastern and western Oban Massif. The rocks occur as large coarse-grained, rounded and, massive bodies deformed together with the bounded gneisses. Ekwueme (1992) has shown that the diorities and charnockite are similar in composition and that the former may be retrogressive product of the latter.
The occurrences of weathering and tectonic activities were observed to have greatly affected the exposed outcrop and such effects from wet season had deformed these outcrops to boulders with reference to their shapes and sizes.
1.1 Location and accessibility
The area is located in the Eastern part of Akamkpa local Government area of theCross River State of Nigeria. It covers an estimated area of about 85sq.KM and constitutes part of the Oban Massif of the South-eastern Nigeria. The map area is largely made up of Ntebachot Akor. New Ntebeji and Ayip Eku all located in Akamkpa Local Government area of Cross River state.
About 90 percent of the area is inaccessible due to thick vegetation, steep valleys and hilly terrains. The only access road across the area is the Calabar-Ekang Road while hunters tracks provide minimal access into the area. | CHAPTER ONE
INTRODUCTION
1.1 Background of Study
Environmental degradation and biodiversity depletion are crucial and disturbing topics among environmentalist today (David, 2014). Probing into the root cause of this problem and the consequences of our actions is the first step towards reducing the rate of environmental degradation and biodiversity depletion. Humanity has always produced waste that are concluded not only the discarded bones of animals slaughter for food but the momentous increase in waste that characterized our society dates from the industrial revolution (Raymond, 2013). Waste is more easily recognized than defined. Waste is an issue that affects us all. Disposing of waste has huge environmental impacts and can cause serious problem if not properly managed. Waste therefore needs to be disposed off in ways which will minimize its negative impacts. Gourlay (2012) defined waste as any residue from a process of production, transformation or uses any substance, material, products or generally any movable object that has been discarded. Something can become waste when it is no longer useful to the owner or it is used and failed to fulfill it’s purpose (Gourlay, 2012). Solid waste according to Miller (2008) is any useless, unwanted or discarded material that is not liquid or gas.
The Longman dictionary of contemporary English defined waste as unnecessary materials, in a house or environment not fit for use. The oxford advanced learners dictionary defines waste as worthless material, rubbish from kitchen, garden or factory, etc that are regularly disposed off. Waste has also been defined by Okocha (2010) as any unwanted material or substances that are harmful to man and his environment which are left or discarded after use. Also included are-by-product lines or materials required by law to dispose off. As a result of the increase in urban development in Nigeria, the country has experienced high growth rate, in terms of increase in population in urban areas and expansion in its major cities. This increasing population has led to continuous increase in human activities which has led to the increase in the amount of waste generated and deposited in the environment (Baird, 2010). These wastes include: food remnants, plastics, polytene, Carbon dioxide, car fumes, industrial waste etc. The increasing generation of waste coupled with the inabilities of the public sectors to provide a suitable means of proper disposal has created an unhealthy situation in which waste are dumped indiscriminately without thoughts to its effect on man and the environment (Vidal, 2010).
According to Janice (2017), the continued increase in population and the consequent increase in waste generation without a corresponding increasing proper waste disposal facilities, has led to a situation in which the waste disposal facilities available can no longer cater for the increasing population, spaces provide for disposal are limited and areas designated for disposal can no longer accommodate these waste most towns and cities have very poor facilities for waste management and in some case only few disposal facilities are available for people to dispose off waste (Onorkarhoraye, 1994). This shows that there has been a poor attitude towards proper waste management both on the part of the government and the people.
Developing countries such as Nigeria has been epitomized by rampaging natural forces, man’s insatiable demand for ever dwindling resources and worsened by an increasing but uncontrolled surge in population growth especially in Nigerian cities (Raymond, 2013). The world may indeed be a beautiful planet, but it is in ever constant danger of destruction and despoliation by nature and man. An unfortunate paradox can however be recognized here, in that while the developed countries of the world are able to effectively combat the destructive physical impacts of their immediate environment due to their access to technology and resources, the developing countries are almost totally at the mercy of nature with very low institutional capacity to respond to environmental threats (Omofonmwan and Osa-Edoh, 2008). Vast lands are lost annually to sea incursion, gully erosion and desertification in developing countries, problems which are being effectively managed in most developed countries (John, 2013).
Infact, in actual sense, waste is generated everyday at a very high level, ranging from fumes generated from cars, generators, power plants and even to industrial waste. This has led to environmental and atmospheric pollution and degradation. This has also led to a situation in which more waste that can be evaluated is created. Waste management could be referred to as the collection, transfer and recycling of waste (Vidal, 2010). The importance of proper waste disposal cannot be over emphasized. Proper waste disposal prevents health problems that improper waste management poses to the environment. Sachets and sachets from uncollected and decomposed garbage can contaminate underground water (UNCHS, 2008). And these have enormous health complications in the urban areas. Olu (2010), observed that when waste are not properly controlled, it causes environmental problems such as blocking of channels of urban streams and rivers major traffic road paths, and at the same time causing health problems like making dysentery etc. it is against this background that this study is conducted to investigate the effects of solid waste management in Abraka, Ethiope East L.G.A of Delta State.
1.2 Statement of the Problem
Environmental issues such as indiscriminate dumping of solid waste and improper waste management will continue to cause health problems and environmental degradation (Janice, 2017). It will continue dominate our discussions and consciousness as it is now clear that the physical, chemical as well as the biological integrity of our planet is being compromised daily (Sada and Odemerho, 1988). The destructive processes are not only continuous but are increasing both in quantum and in rate. While some of the impacts such as loss of biodiversity might be gradual, there are hosts of communities around the world today that are being consumed by indiscriminate waste dump etc., with loss of aquatic lives and billions of dollars worth of properties being lost due to environmental degradation (Kaka, et al, 2010).
Over the years, developing countries such as Nigeria has been rampaged with serious environmental problems such as indiscriminate waste disposal, pollution, flooding, degradation, spillage, among others. Environmental problems have been topical issues in recent time which needs urgent attention. Vidal (2010) noted that the manifestation of these impacts includes; urbanization, deforestation, desertification, overpopulation and all kinds of pollution. These impacts have both negative and positive effects on the natural environment. The unwise use of the natural environment due to ignorance, poverty, overpopulation and greed amongst others has led to the degradation of the environment. The charges (degradation) occur as most Nigerian cities attempt to adjust their seemingly endless wants and desires for food, shelter, recreation, infrastructural facilities, and so on to the land and other resources available to them (NEST, 2012). As observed by Raymond (2013), these land use activities contribute to the overall development of the country but they equally produce negative impact on the environment. These negative impacts are referred to as environmental degradation which implies “abuse of the environment” due to improper resources management and waste disposal (Baird, 2010).
Solid waste management has emerged as a major environmental threat for cities in developing countries worldwide (Van de Klundert, et al., 2013). In a survey released by UNDP in 1997, 151 mayors from around the world ranked insufficient solid waste disposal as their second most urgent urban challenges surpassed only by unemployment and followed by urban poverty. Solid waste management has gained notoriety in Nigeria today because of its visibility and the embarrassment it has constituted to the image of the industrialized and developing. Only few state capitals have been able to put in place fairly sustainable urban waste management programmes. It is therefore a common site to find mountains of waste scattered all over our cities for days or even weeks with no apparent effort displayed at getting rid of them, even with the attendant risk of air and ground-water pollution (David, 2014).
The problem of the deposal of savage and refuse is quite serious because of the rapid rate of generation of non-biodegradable materials such as plastics (Molles, 2005). Environmental conditions in cities have gradually deteriorated due to the rapid growth of the cities and the attendance inability of social services and infrastructures to keep pace with the rate of growth. Inadequate storm drains, dumping of refuse in drainage lines and construction of houses close to and even on the natural water channels have been shown to be responsible in that order for the increasing cases of flood in the urban centers. Environment problems such as indiscriminate waste disposal is associated with the increasing growth of urban slums including overcrowding in squalid housing conditions, poor quality or unavailability of basic infrastructures and social services, such as water and sewage facilities and even lack of access routes (NEST, 2012).
Environmental degradation mostly caused by improper waste disposal has destroyed the natural landscape of most developing countries. It is observed that improper waste disposal has negative impact on the natural quality of the environment (NEST, 2012).
Environmental pollution can be categorized into three groups. These are air or atmospheric pollution, aquatic or water pollution and land or surface area pollution. The World Health Organization (WHO) (2010) defined air pollution as “limited to situation in which the outer ambient atmosphere contains materials in concentrations which are harmful to man and his environment”. According to Janice (2017), man’s activities on the earth surface have largely degraded the quality of the lower atmosphere. The growth and development of industries and urbanization has contributed greatly to the excess carbon monoxide produced by combustion and other human activities. Carbon monoxide reacts with the blood vessel and prevents it from taking up oxygen and the people are suffocated (Baird, 2010).
In Nigeria, several rural towns that had in the past enjoy fresh and dry air are currently experiencing air pollution problems due to improper waste disposal (Obajimi, 2008). This is due to industrialization process and expansion in human activities. Aquatic or water pollution is the discharge of unwanted biological, chemical and physical materials into water bodies from man’s environment. The pollutants are usually chemical, physical and biological substances that affect the natural condition of water. This incidence is responsible for the wide spread water contamination in most industrialized and developing countries (Nwilo and Olusegun, 2017).
It has been discovered that solid waste has equally flooded the water ways in urban centres. Land surface pollution is the occurrence of unwanted materials or waste on land. The commonest pollutant on land is the waste products that are often scattered on land area in the cities. According to Onwioduokit (2008), most environmental problems are due to the production or consumption of goods whose waste products translates easily into pollutant. Sada (1981) and Ayeni (2008) believed that the emergence of urbanization is responsible for the rapid accumulation of solid waste. Generally, it would appear that the growth of urbanization and industrial development coupled with improper wastes management control have added a great dimension to land area pollution in industrialized and developing countries. Generally, there are other environmental problems resulting from the humanization of the natural environment, only some of the important impacts are discussed (Ogbobi, 2010).
Other problems like shortage of manpower, finance, attitude of people towards waste disposal, lack of disposal sites or location etc. have contributed to the continues existence of uncontrolled or improper disposal of waste in the environment (Janice, 2017).
1.3 Aim and Objectives
The aim of this study is to examine the effects of solid waste management in Abraka, Ethiope East L.G.A of Delta State, with the view to suggest possible positive solutions to the problems. However, the specific objectives includes to:
identify refuse dump sites in Abraka;
determine the various types of waste generated in Abraka;
examine the factors responsible for the high rate of waste generation in Abraka;
examine the effects of solid waste management in Abraka region;
identify the various methods of waste disposal and management in Abraka;
suggest possible solutions to the problems of improper waste disposal and employ suitable methods of disposing wastes in Abraka.
1.4 Hypotheses
The following null hypothesis will be tested in this study;
Solid waste management has no significant effect on the environment of Abraka region.
There is no significant relationship between the effects of solid waste management and the factors responsible for the high rate of waste generation in Abraka.
1.5 Significance of the Study
This study is very necessary, as the effects of solid waste management on the natural are enormous. Although, there are available literatures on the topic, not much is known by a vast number of the population about the adverse consequence of accumulated waste in the environment. The presence of improper waste disposal in Abraka poses a very great threat, not only to the environment, but also to the residents in Abraka.
The recommendation that will be made from this study will help to preserve and improve the natural quality of the environment, taking into account the circumstances and particular requirements of developing countries and any costs which may emanate from their incorporating environmental safeguards into their development planning and the need for making available to them, upon their request, additional international technical and financial assistance for this purpose. It will enlighten the general public on the dangers of degrading the environment through indiscriminate waste disposal. It will therefore suggest control measures and mitigation techniques to conserve and preserve then natural environment against degradation (solid waste management).
It is not unusual to find heaps of refuse along major roads, streets, markets places, moats, etc. In Abraka, the presence of this indisposed waste has greatly defaced the environment and also poses a great threat to human life. This study highlights the dangers of indiscriminate dumping of waste; benefits of proper waste management etc. It will also give useful information on the important and need for proper waste disposal in Abraka with respect to health and the environment. In conclusion, the study is to aid in upgrading available information on waste disposal and management in Abraka. | CHAPTER ONE
1.0 INTRODUCTION
1.1 BACKGROUND OF THE STUDY
The development of soil erosion began when man settled down and started turning pasture land into farmland. The intensive exploitation of the land disturbed the natural soil vegetative cover and exposed its, surface to the effect of erosive agents and to introduce such forms of agriculture that did not destroy the land the devastation of land by erosion often led to the down fall of civilization e.g in Mesopotamia Syria, China and else where.
According to Robert. M. (1984), Erosion is manifested by the determination of soil surface effected by exogenous forces, especially water. Ice wind and, man as the significant anthropogenic factor. The disturbance of soil surface is accompanied by the removal of the detached soil particles by the force of kinetic energy of some of the erosion agents, namely water and wind and the deposition of this matter with a decrease in this energy. Erosion is caused by surface num off and result complex natural process. Water erosion is caused by precipitation. Areas with a low precipitation usually have a small surface num off because precipitation water infiltrates into the soil is consumed by vegetation erosion which may also be broadly cause by a natural factor organ.
It can also be carried by improper channeling neglect of natural sewage systems and obstruction of naturally sewage by buildings. Form land and other unplanned structure causes a great deal of damage.
Although the nature of soil within the area under consideration is mostly sandy with a very low water storage capabilities. Practical observation orchestrated form visit to those site prone to erosion have shown that their may be possibility of erosion if the nun off water is not properly channel e.g the nature of the soil. In sandy soil they can form a very good soil material but danger exist if the water table is near or surface nun off is not adequately channeled. The sandy easily eroded a way from it position their by causing or may lead to fully erosion.
Furthermore, erosion is seen as one of the most serious defects in contemporary residential buildings, it is observed here that apart form it causing rapid destruction of structure / buildings, it also result to severe damage to the soil and in severe case it adversely affect the health of the occupants.
1.2 STATEMENT OF PROBLEM
A certain condition or factor can make a soil or structure / building to loose their Sharpe effectively or ineffectively attain their maximum structural physical and economic life span. It has been seen that a number of fact observed to be responsible for the in-adequate or in-appropriate functioning channeling of sewage surface nun off water at the due time. These in turn expose the building site to the danger of erosion which accelerate their dilapidation. Among the factors or improper channeling / neglect of natural sewage system and obstruction of natural sewage by building without following the local authorities rules dropping of refuse in the drainage ways. Erosion plays a critical role in dilapidation of building and visible in construction industry as one of the most serious defect in contemporary residential buildings. All soils can suffer erosion but some are more vulnerable than others. Soils with dispersible subsoils, for example, are subject to serious erosion by funneling and gully formation.
1.3 RESEARCH AIMS AND OBJECTIVE
The major purpose of this study is to determine. The effective way of controlling erosion in a construction site prone to erosion problem.
1) Identity the various causes of erosion in building sites.
2) Examine the appropriate materials and (new and old) used in controlling the erosion.
3) Determine the most appropriate materials and techniques required for the controlling it.
4) To recommend measure if implemented will lead to effective control of erosion in a construction
1.4 RESEARCH QUESTIONS
The study sought to answer the following research questions
1) What are nature and various causes of erosion in building sites
2) What are the process to be applied in erosion control.
3) What are the various types of materials to be used in controlling erosion
4) If implemented will lead to effective control of erosion in an erosion prone site
1.5 SIGNIFICANT OF THE STUDY
The significance of this study shall include the follow:
1) Contractors and engineers shall know how to control erosion in an erosion prone site.
2) The engineers and the general public will because more aware on the importance of erosion control in a site.
3) Lecturers, students consultants and other stakeholders in the construction industry will be theoretically & technically equipped on how to control erosion in an erosion prone construction site.
1.6 STUDY OF AREA
This study was delimited to the problem of erosion in a site prone to erosion. It focused on the type and magnitude of erosion at site in Anambra state and also looked at the specific remedial techniques to that building site will function effectively and efficiently. Attempt should be made to look into laboratory experimentation of the material used for effective control of erosion in building site prone to erosion. Ekwulobia erosion is gully erosion-gully erosion is of concern due to periodically intense rainfall and a large average of erodible soils. Effective design of gully control system must consider the gully network as a whole and be based on geomorphologic indicators such as type of network, order and stage of development.
1.7 DEFINITION OF TERMS
According to Grolie (1990). Erosion is the wearing away of the earth surface by the action of water.
According to Milos Holy (1987). Building is permanent or temporary structure enclosed within exterior walls and a roof and including all attached apparatus. Equipment and fixtures that cannot be removed without cutting into ceiling floors or walls. In the year 1960 Bernard Huss define soil as the top layer of the earths surface in which plants an grow consisting of rock and mineral particles mixed with decayed organic matter and having the capability of retaining water. | ABSTRACT
A resistivity survey was made in some part of PTI dumpsite in order to determine the quality of the ground water in that area. The survey consisted of 5 electrical soundings which were carried out using the Schlumberger array configuration with a current electrode separation of 126m. The data was interpreted by computer aided iteration techniques using the Resistivity modeling Software Application. The result of the interpretation shows four to five distinct geoelectric layers with resistivity ranging from 112.7Ωm to 426.8Ωm. Difference in apparent resistivity was assumed to be due only to differences in specific conductance of groundwater in the saturated zone. The result of the survey has shown that the aquifer in the study area has not yet being contaminated.
CHAPTER ONE
Introduction
1.0 BACKGROUND OF STUDY
Groundwater is commonly understood to mean water occupying all the voids within a geologic stratum. Groundwater is one of the nation’s most valuable natural resources; it is the source of about 40 percent of the water used for all purposes exclusive of hydropower generation and electric power plant cooling. Surprisingly for a resource that is so widely used and so important to health and to the economy of the country, the occurrence of ground water is not only poorly understood but is also, in fact , the subject of many widespread misconceptions. Common misconception includes the belief that ground water occurs in underground rivers resembling surface streams whose presence can be detected by certain individuals. These misconceptions and others have hampered the development and conservations of ground water and have adversely affected the protection of its quality.Groundwater occurs everywhere but sometimes its availability in economic quantity depends solely on the distribution of the subsurface geomaterials that are referred to as the aquifers. This implies that where groundwater is not potentially endowed enough, there may be either complete lack or inadequacy due to increasing industrial and domestic needs.
Pollution occurs when the concentration of various chemical or biological constituents exceed a level at which a negative impact on amenities, the ecosystem, resources and human health can occur. Pollution results primarily from human activities. There are different sources of pollution. When they are chemical or biological constituents creating pollution they are known as contaminants. Contaminants degrade the natural quality of a substance or medium. It can either be organic or inorganic.
Surface resistivity methods have been employed successfully for detecting and mapping ground-water contamination under a variety of conditions. The method is based on the fact that formation resistivity depends on the conductivity of the pore fluid as well as the properties of the porous medium. Under favorable conditions, contrasts in resistivity may be attributed to mineralized groundwater with a higher than normal specific conductance originating at a contamination source. Success with surface resistivity methods depends to a large extent on a good knowledge of subsurface conditions. Conditions favorable for delineating zones of contamination include uniform subsurface conditions, a shallow groundwater table, and good electrical contrast between mineralized and natural water.
One of the primary problems in field investigations of groundwater pollution is locating the contaminant plume. In most cases, the goal is to positively locate the pollutant and its movement by test holes and direct monitoring. In the interest of efficiency the investigative areas should be as focused as possible. In many cases a general knowledge of local hydrogeology allows a reasonable initial estimate of pollutant direction; in other instances even this may be lacking. Drilling of sampling holes on a hit-or-miss basis is both time-consuming and expensive. It can also be destructive to the property involved. Under certain subsurface conditions, surface geoelectrical profiling can quickly and cheaply locate the general location of the plume and identify areas most feasible for sampling and monitoring.
Numerous investigations have established the usefulness of surface electrical resistivity as a tool in the detection of ground water contamination.
1.1 Definition and Causes of groundwater pollution
Pollution has been found to be much more widespread than we had believed only a few years ago. Polluted ground water may pose a serious threat to health. Pollution of ground water refers to any deterioration in quality of the water resulting from the activities of man. Most pollution of ground water results from the disposal of wastes on the land surface, in shallow excavations including septic tanks, use of fertilizers, leak in sewers and pipelines. The magnitude of any pollution problem depends on the size of the area affected and the amount of the pollutant involved, the solubility, toxicity, and density of the pollutant, the mineral composition and the hydraulic characteristics of the soils and rocks through which the pollutant moves, and the effect or potential effect on ground-water use.
1.2STATEMENT OF PROBLEM
Here this study focuses mainly on the impact of Groundwater pollution in a dump site area and how it can be evaluated using resistivity method. But first I will like to discuss briefly about the impact of pollution on Groundwater before giving reasons of using resistivity method on ground water pollution in a dump site.
1.3 AIM AND OBJECTIVES
The aim of this work is to detect, delineate and denominate the extent of contaminant intrusion on ground water in an area, with the following objectives in mind:
Ø To study the geo electrical properties of the sub surface to depth in other to estimate contamination degree.
Ø To uncover the direction of pollutant flow relative to the ground water flow.
Ø To assess and map the vertical and lateral extent of contaminated groundwater into sub surface and how much ground water area it covered.
Ø To distinguish between polluted and non - polluted zones with respect to the groundwater contamination.
1.4 SIGNIFICANCE OF STUDY
The significance of the above study is important in following ways:
v It will provide useful information on the condition of ground water at dump site areas which can serve as a useful tool in environmental impact assessment (EIA), of that area.
v Information about water flow direction will assist in the design of efficient and cost-effective monitoring networks and remediation strategies of ground water pollution.
v Geoelectric details of the subsurface gotten from this study will give sound knowledge of the sub surface geology including infiltration and percolation process is prerequisite for managing contaminant transport in the saturated or aquifer zone.
1.5 SCOPE OF STUDY
In this present study, VES data were collected from the dumpsite area of PTI, Effurun Delta State. This geoelectric data of the subsurface were then used to detect the source of the pollution, estimate the degree of contamination, lateral and vertical extent covered, and map out zones of anomalies and estimate the spread rate.
1.6 LIMITATIONS TO STUDY:
Electrical resistivity profiling is simple in concept but has a number of significant practical limitations.
Ø Equipment range: The extreme limit for spread of the current electrodes, and consequently the depth of penetration of the current generator and the resistivity characteristics of the soil being measured. Highly resistive layers such as thick unsaturated zone require considerable current before the underlying saturated material can be sensed.
Ø Physical obstructions: In many situations, it is difficult to establish a long continuous electrode spread or profile line because of physical obstructions. These may include rocks, trees, bulidings, paved areas and the like.
Ø Electrical interferences: A careful check must be made of the area to be surveyed for any electrical inducing or conductive features. These include overhead and buried power lines, metal fences, above-ground and buried water lines, railroad tracks, and conductive pipes of all kinds. As a general rule one must be at least as far away from such interference as the "A" spacing.
Ø Topographic variations: The model assumes that the resistivity layers are uniform in thickness and infinite in extent. In hilly or rugged terrain, it becomes impossible to determine whether the observed change is due to subsurface variation in hydrogeology or to topographic changes.
Ø Hydrogeologic variations: Changes in soil type zone can mask the effects of pore-water resistivity change. The presence of silt and particularly clay will lower the apparent resistivity substantially and can easily be mistaken for a change in pore-water resistivity. Accordingly where such materials may occur, electrical interpretations should be made with reservation.
1.7 PROCEDURES INVOLVED IN THE STUDY
The following procedure is recommended for surface resistivity profiling:
Develop a hydrogeologic concept for the area to be investigated. Available geological and ground-water studies should be reviewed. If available, boring logs and water quality data should be obtained. From these, the pattern of ground-water flow and general resistivity model can be ascertained.
Ø Make a field survey of the area.
Ø Determine Profile Location: Based on the results of items 1 and 2, the selection of profile locations can be made. The profile line should cross the anticipated plume location, beginning and ending clearly on either side of the probable contaminated zone.
Ø Make Field Preparations: The line should be cleared and the electrode positions clearly marked in advance. Much time during the actual profiling can be saved by good site preparation. Equipment, especially condition of batteries and integrity of electrical wire, should be checked carefully before proceeding to the field.
Ø Make Vertical electrical sounding: Atleast one electrical sounding and preferably more should be made at the site to ascertain the most appropriate "A" spacing(s). Ideally these soundings should be made in an uncontaminated zone. The soundings should confirm the hydrogeologic model developed from item 1.
Ø Run Profiles: The profiles are then run at the selected A spacings and at a station separation no more than one-third the estimated plume width. Preliminary calculations of apparent resistivity should be made in the field; this allows for additional readings to be taken if results seem unusual or a region of electrical anomaly is encountered.
Ø Perform analysis of Data: Analysis is made from plots of the calculated apparent resistivity against profile stations. The contaminated region should then appear as an anomalous low in the profile plot. If such a low does not appear, the sounding curve, available information and field conditions should be reexamined for a more sensitive electrode spacing, possible electrical interferences, or infeasibility of the method due to lack of sufficient pore-water contrast.
1.8 BASIC TERMS IN GROUNDWATER STUDY.
1.8.1 AQUIFER: An aquifer is a ground-water reservoir composed of geologic units that are saturated with water and sufficiently permeable to yield water in a usable quantity to wells and springs. Sand and gravel deposits, sandstone, limestone, and fractured crystalline rocks are examples of geological units that form aquifers. Aquifers provide two important functions:
(1) They transmit ground water from areas of recharge to areas of discharge, and
(2)They provide a storage medium for useable quantities of groundwater. The amount of water a material can hold depends upon its porosity. The size and degree of interconnection of those openings (permeability) determine the materials’ ability to transmit fluid.
UNCONFINED AQUIFERS
An unconfined aquifer is one in which a water table varies in undulating form and in slope, depending on areas of recharge and discharge, pumpage from wells, and permeability. Rises and falls in the water table correspond to changes in the volume of water in storage within an aquifer.
Figure 1 shows an idealized section through an unconfined aquifer; the upper aquifer in is also unconfined. Contour maps and profiles of the water table can be prepared from elevations of water in wells that tap the aquifer to determine the quantities of water available and their distribution and movement. A special case of an unconfined aquifer involves perched water bodies (Figure 1). This occurs wherever a groundwater body is separated from the main groundwater by a relatively impermeable stratum of small areal extent and by the zone of aeration above the main body of groundwater. Clay lenses in sedimentary deposits often have shallow perched water bodies overlying them. Wells tapping these sources yield only temporary or small quantities of water.
CONFINED AQUIFERS
Confined aquifers, also known as artesian or pressure aquifers, occur where groundwater is confined under pressure greater than atmospheric by overlying relatively impermeable strata. In a well penetrating such an aquifer, the water level will rise above the bottom of the confining bed, as shown by the artesian and flowing wells. Water enters a confined aquifer in an area where the confining bed rises to the surface; where the confining bed ends underground, the aquifer becomes unconfined. A region supplying water to a confined area is known as a recharge area; water may also enter by leakage through a confining bed. Rises and falls of water in wells penetrating confined aquifers result primarily from changes in pressure rather than changes in storage volumes. Hence, confined aquifers display only small changes in storage and serve primarily as conduits for conveying water from recharge areas to locations of natural or artificial discharge.
Figure 1: Schematic Cross-sections of Aquifer Types (Modified after Hartan et al, 1989)
LEAKY AQUIFER
Aquifers that are completely confined or unconfined occur less frequently than do leaky, or semi-confined, aquifers. These are a common feature in alluvial valleys, plains, or former lake basins where a permeable stratum is overlain or underlain by a semi-pervious aquitard or semi-confining layer. Pumping from a well in a leaky aquifer removes water in two ways: by horizontal flow within the aquifer and by vertical flow through the aquitard into the aquifer.
1.8.2 AQUITARD
An aquitard is a partly permeable geologic formation. It transmits water at such a slow rate that the yield is insufficient. Pumping by wells is not possible. For example, sand lenses in a clay formation will form an aquitard.
1.8.3 AQUICLUDE
An aquiclude is composed of rock or sediment that acts as a barrier to groundwater flow. Aquicludes are made up of low porosity and low permeability rock/sediment such as shale or clay. Aquicludes have normally good storage capacity but low transmitting capacity. |
