Assessment on effect of soil excavation in Abraka

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;

1.     To identify the various sand mining/excavation sites along River Ethiope in Abraka and Eku.

2.     To investigate the effects of sand excavation on coastal areas where excavation is done in Abraka-Eku region along the River Ethiope.

3.     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;

1.     Sand excavation has no significant impact on the environment of Abraka-Eku along River Ethiope.

2.     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.

1.5.2 Relief and Drainage

The relief of Abraka and Eku falls under lowland types of land scape and is grouped under the interior coastal lowlands of Western Nigeria. Its boundary is marked in the North by edge of the basement complex of the Western highlands and in the South by the quarter many deposits of the coastal margin (Aweto, 1985).

The entire Abraka and Eku region is drained by River Ethiope. The River takes its source from Umuaja and flows through Obiaruku to Abraka, Eku and joins the Benin River. The river has some tributaries that are regarded as streams know as “Urhiesoso and Urhierhiugbiroba” both are found at Urhuovie. Other tributaries are Orimhonre River and Orogodo River at Urhuonigbe which originate from River Niger and the river is dendritic in pattern.

1.5.3  Geology and Soil

The study area consists mainly of sedimentary rock formations deposited in three cycles of marine transgressions. According to Odemerho (2007), the surficial geology comprises of the Sombreiro-Warri Deltaic plain formulation. The Sombreiro-Warri formation covers much of the Deltaic plain, an area also referred to as the “Urhobo plain” (Aweto, 1987). The lithologies of these surficial materials show evidence of a variety of depositional environments that include deltaic, fluvial and ages that range from Miocene through Pleistocene to the recent (Wright, 1985). At the end of the Pleistocene Ice Age, the gradual rise in sea level and ground water table produced the requisite hydromorphic environment for the podzolization of the base-deficient and deeply weathered sand-rich deltaic plain alluvium deposits to form the “white sand”, especially in the swamps and abandoned river floodplains where savanna type of vegetation currently predominates (Aweto, 1987; Thomas, 1994).

The sedimentary rocks are rich in petroleum and natural gas, which are often trapped within their growth and antithetic fault structures. The primary source rocks for petroleum in this region are the interbedded marine shale fades of Agbada and Akata formations.

Abraka soil is acidic in nature while Eku has a rich soil. Abraka and Eku soil varies from coarse through medium to fine grained soils. The soils of Abraka and Eku can be said to be sandy loam. The colour of the soil is greenish brown to reddish brown and then to brown. The light green colouration characterizes the entire sandy portion of the soil, while the reddish brown colouration depicts the presence of ion oxide in the soil. This colouration depicts the availability of mineral matters and moisture. Abraka soil is poorly structured in relation to its type in terms of grain size, pore spaces which greatly influences the rate of percolation and capillarity, aeration and the rate of evaporation while Eku has a well structured soil which favours agricultural production (Akinbode and Ugbomeh, 2006).

1.5.4  Climate and Vegetation

Abraka and Eke falls under the tropic al climate of Koppen classification of 1918 which Nigeria falls under (Iloeje, 1981). The region falls under the tropical rainforest vegetation. This implies that Abraka and Eku is located in Nigeria fall within the humid sub-equatorial climate in Nigeria (Iloeje, 1981). It is dominated by two prevailing air masses: the tropical maritime air mass (MT) or south westerly monsoon air mass which is warm, moist and humid prevails throughout the wet season from March to October and the tropical continental air mass which is prevalent during the dry season. The tropical continental is dry and dusty and it is associated with harmattan season in the area (Efe, 2006). This zone extends from the coast to roughly inland and falls within areas with an annual rainfall distribution between 2000mm-4000mm (Akinbode and Ugbomeh, 2006). The distribution of rainfall pattern during the year is characterized by the double maximal regime; the two periods of maximum rainfalls being in July and September. Temperatures are relatively high throughout the year with sharp seasonal variations throughout the year. The mean annual temperature is about 31.5⁰C while annual range is 2⁰C (Akinbode and Ugbomeh, 2006). The relative humidity of the atmosphere is usually high throughout the year owing to the dominance of the tropical maritime air mass. During the rainy season, the average relative humidity of the air is usually over 83%. The air is less humid during the dry season but the relative humidity of the air is still over 65% (Akinbode and Ugbomeh, 2006). The seasonal pattern of the area is summarized below:

i.                   Long wet season: This starts from mid March to July. It is the season with heavy rainfall and high humidity.

ii.                 Short wet season: This follows the August break and occurs between September and October.

iii.              The short dry season: This is the August break. It lasts for about two weeks in the month of August.

iv.              Long dry season: This is the harmattan season between November and mid March.

Abraka and Eku experiences heavy rainfall during the wet season and intense heat during the dry season owing to its location in the Niger Delta zone with the continual monsoon wind blowing from the Atlantic Ocean and also a continuous shift in the Inter-Tropical Discontinuity (ITD) due to the movement of air masses. Abraka and Eku is located on the equatorial rainforest which is evergreen forest and consist of three canopies of trees which are, the upper layer of which is about 60m tall, middle layer which is about 40m tall and the lower layer which is about 30m in height. The three major vegetation types in Abraka and Eku includes; the tropical rainforest belt, temperate grasslands and the grassland vegetation remains one of the key important factor which affect the climate of Abraka and Eku region. Vegetation provides lumbering, medicinal purpose, food, income and employment to the people of Abraka and Eku region.

1.5.5 Population

Abraka combined together are growing urban centers with a rapid population tilting to one million as compared to Eku whose development is still at its infancy stage (Evans, 2017). The population figures of Abraka and Eku stands at about 684,220 and 265, 332 people respectively according to the 2006 population census (Ethiope East L.G.A Population Statistics, 2007).

1.5.6 Socio-Economic Activities

The socio-economic activities of Abraka and Eku varies from urban to rural areas. They include agricultural activities (such as farming, hunting, fishing, etc.) trading/commerce, transportation, education and government office work.

Agriculture: Agriculture is the mainstay of the economy of Abraka and Eku dwellers. The people of Abraka and Eku engage in hunting at the government reserve area close to Edo state and various bushes around the region. Fishing activities mostly take place at River Ethiope as majority of the populace are fishermen who rely heavily on River Ethiope for their source of livelihood. The engage in both subsistence and commercial farming which includes mixed cropping, plantation agriculture, crop rotation system and land tenure practice. Food crops grown in Abraka and Eku region are maize, yam, cocoyam, cassava and millet while cash crops grown are plantain, banana, mango, cashew, guava and pearl. Rubber and plantain plantation farming is also common within this region. The predominant occupation of rural dwellers in Abraka and Eku is farming. Most farmers produce locally made food items for the entire population.

Trading/Commerce: One of the major human activities in Abraka and Eku is petty trading which is carried out in all parts of the town. Trading and commercial activities in Abraka and Eku ranges from street hawking, small scale business, shops, retails and whole businesses and supermarkets to include the popular Abraka and Eku main market which attracts people from far and near. The market has been a major source of income for most urban and rural dwellers of Abraka and Eku region who depend on trading for their source of livelihood. The town also comprises of some proportion of the population of artisans like mechanic, welders, tailors and carpenters.

Abraka and Eku region entails sales of varieties of food crops which are produced locally such as yam, plantain, banana etc alongside none food products. The physical structure of the Abraka and Eku market (centre of commerce) and other neighbouring stores being poorly planned has really affected the rate of commerce with regard to drainage, indiscriminate waste disposal at market site which has a resultant effect on the health standard of food crops for consumption in sold the market.

Crafts and Local Industries: The region of Abraka and Eku engage primarily in craft making such as local mats, cane, bead making, carpentry, artisan (fashion designers, stylist, hairdresser, decoration, etc), furniture, and other craft works. Local industries found in these regions include cassava mills, saw mills, palm oil mill, plantain plantation, bakery, pure water factory, sand dredging etc. These local industries have in one way or other improved the socio-economic activities of the areas.

Transportation: Transportation provides mass employment for the timid unemployed youths in Abraka and Eku Okoda business. These transportation activities include motor-bike riding (Okada) for transportation and Keke (Tricycle) and transport companies such as Delta State Urban Mass Transit Scheme (popularly known as Udhuagha Park), Agofure Transport Company, Steve Nnam motors, Muyi line, Osato motors, among others.

The provision of employment has significantly been affected by the motorcycle business or public transport system (buses) and has increased the standard of living of motorcyclist and also a corresponding increase in the population of Abraka region. Conclusively, it could be deduced systematically that the motorcycle mode of transportation has aided not only in the facilitation of movement of people and information but also in provision of employment, income and increases the standard of living of both motorcyclist and commercial transports.

Tourism: The Abraka and Eku tourism region is another economic activity carried out in the region. It is located in the Niger Delta area of Nigeria, along the river Ethiope of Abraka. The Abraka River Resort Motel which is the largest, best developed tourist centre with accommodation facilities of high standard is characterized by a well stretched beach space, water oriented leisure activities etc. Others includes the turf club at Oria, an international standard pool centre along the River Ethiope, the Gordon Motel which has over a hundred (100) chalets offering quite a natural rainforest environment of clean-clear water with alternating swift and slow river regime, the bamboo game village, Mega bar and restaurant at Ajalomi etc.

Civil Service: Majority of the population in Abraka and Eku is made of public servants who are mostly Delta State University workers, students, teachers, health workers in the Government General Hospital in Abraka and Eku Baptist Government Hospital.

Education: The people of Abraka and Eku place prenium on education. Town unions, private individuals and associations, being part of voluntary agencies, have played active roles in the development of educational infrastructure, tourism and recreational faculties in the region. The provision of health facilities ranks second to education in priority.

          Educational centres in Abraka and Eku includes the Delta State University, Abraka, Baptist Seminary located at Eku, School of Mid-Wifery located at Eku, Institute of Educational Research Center located at Eku (no longer functioning), Aganbi Secondary School, Eku, Abraka Grammar School, among others.