1.0 Chapter one

Introduction

1.1 Background to the study

River erosion as an environmental problem is an age-old phenomenon.. The National Erosion and Flood Control Action Plan Committee (2010) defined river erosion as a condition which exists when discharge of a river or stream cannot be accommodated within the margin of its normal channels so that waters spread over adjoining land. River erosion  is one of the most common environmental hazard in Nigeria (Etuonovbe, 2011).There is increasing vulnerability of populations and infrastructure to  erosion  related hazards. Although River erosion is one of many hazards occurring in human environment, its effects are significant both in terms of discomfort, destruction of lives, properties and pollution. The severity of flooding has been reckoned with, by the level of damage done (Williams, 2011). Erosion not only damage property and endanger the lives of humans and animals, but have other effects as well. Erosion and its effects all over the world are becoming a threat to sustainable development in human settlements (Aderogba, 2012). Cross river is a lucky state  when it comes to water resources. But we must know that erosion disturbance in Nigeria, Africa and all over the world, are environmental challenges that need prevention to ensure sustainability (Akolokwu, 2012). River erosion is one of the major environmental crises one has to contend within the century. This is especially the case in most wetlands of the world (Bariweniet al., 2012). The reason for this is the general rise in sea level globally, due to global warming as well as the saturated nature of the wetlands in many parts of the world such as Nigeria. River erosion occur on many waters periodically, these rivers overflow as a result of excess rainfall etc. One good thing about the river overflows is the fact that it deposits sand; silt and debris on the surrounding land as flood waters flow into the banks. After the river water calmed and return back to its normal flow, the materials deposited will help increase the fertility of the land. The organic materials and minerals deposited by the river water therefore maintain the soil fertility and productivity (Abowei and Sikoki, 2010). Erosion that happened in some parts of Nigeria in 2012 including  cross river is the country’s worst in living memory (Social Action, 2012). River erosion are among the most frustrating natural disasters in the universe, claiming more lives and leading to more damage of property than any other natural phenomena. In Nigeria, though not occurring in terms of claiming lives, flood displaces and affects more people than any other disaster; it also brings about more damage to properties. At least 20 per cent of the population is at risk from one form of flooding to another. Erosion  has been hazardous to communities and institutions in Nigeria. It has destroys both the built-environment and undeveloped plan.

River erosion is also the natural phenomenon (geological process) which is caused by natural force; it can be more accelerated when the process is influenced by human activities (human induced erosion). It is considered that the accelerated river erosion is a serious global problem and widely recognized (Emeribeole 2015). With the accelerated erosion, it can affect agronomic/biomass productivity (on-site effect) and flooding, sedimentation of reservoirs, siltation of agriculture field and decrease of water quality downstream (off-site effects). The two important agents of erosion are wind and water (Yoade, Adeyemi and Adelabu, 2020). Erosion by water has been identified as the most severe hazard that threatens the protection of soil (Yoade et al. 2020). The erosion process starts with sheet erosion (the washing out of surface soil from arable land), followed by rill erosion with the concentration of overland flow into small rivulets in the fields and finally the gully erosion. When the eroded channels are larger than 30cm deep, erosion reduce fertility status of topsoil, soil productivity, soil organic matter content. River erosion is a natural process of soil material removal and transportation through the action of erosive agents such as water, wind, gravity and human disturbance. It is becoming clear that the transport of eroded material from land to water by overland flow via runoff is an important environmental problem promoting the eutrophication of surface waters, damaging freshwater ecosystems and causing microbial contamination of surface water sources (Tabiri 2015). Erosion is generally recognized in several different forms; rill, splash, sheet and gully erosion. Soil loss by runoff is a severe ecological problem occupying 56 % of the worldwide area and is accelerated by human induced soil degradation (Tabiri 2015). On a global scale erosion by water affects 1.1 billion hectares of soil worldwide thus representing 56% of the total degraded land area while wind erosion affects 28 % of total degraded land area (Okoye 2019). River erosion is a single major process responsible for the loss of billions of tones of soil worldwide (Okoye 2019) and it remains the world‟s largest environmental problem threatening both plants and animals (Abegbunde et al., 2006). River erosion in Africa threatens food and fuel supplies and can contribute to climate change. For over a century, governments and aid organizations have tried to combat river erosion in Africa, often with limited effect. Currently 40% of soil in Africa is degraded. River erosion and erosion-caused land degradation are serious problems in Nigeria. Low levels of crop yields observed in the some parts of the country are partly due to severe levels of past erosion and resultant decline in soil productivity. Borno as a state in Nigeria suffers a great deal of river erosion, in several parts of the state under different geological, climatic and soil conditions. But the degree of occurrence varies considerably from one part of the state to the other. It is to this the study centres on Impact Of River Erosion On Physical Landscape In Itigidi Abi Lga Cross River State

1.2 Statement Of The Research Problem

The concern on environmental problems is global, international organizations, government and individual across the world are concerned about the increasing pace of environmental problem. The engine that drives all forms of man’s activities such as social, human, economic and cultural activities have continuously been abused, neglected and destroyed by man (Adugna, et al., 2015). Pollution, deforestation, erosion, flooding, landslides, global warming etc. are the aftermaths of this abuse in and on the ecosystem. By virtue of Nigeria’s spatial extent and its location, in the tropical latitudes, the country encompasses various climatic regions and physiographical units, which has severely exposed the country to the destructive influence of climatic induced hazards including flooding, erosion, drought and desertification.

 River erosion poses a very serious setback to agricultural productivity in most part of the cross river states, and the extent of the spread and damage has reached an alarming proportion that if efforts are not intensified to remedy the ugly situation, it could cause untold hardship and put the communities in a state of jeopardy (Adugna, et al., 2015). The implication of the continuous spread of erosion was identified by Lal (1998) as disruption of hydrological systems, poor water quality, low agricultural production among others, and these is an anathema to achieving sustainable livelihood and human sustainability. The interplay and interaction of both natural factors (rainfall, relief, soil) and human activities (crop management and land use) makes the evaluation of soil loss and sediment yield difficult. Ananda and Herath, (2003) asserted that water erosion is also influence economic, social and political component aside the biophysical parameters also play significant role in influencing River erosion. In view of this, evaluation and assessment of soil loss and sediment yield in an accurate and timely manner is imperative. The continuous destruction of agricultural land resources across the globe has led to the development of numerous models for soil loss estimation (MUSLE, USLE, MMF, EPIC, WEPP, and SWAT) among others.

River Erosion, which has been a perennial problem in the study area  has caused much havocs and difficulties to the inhabitants of the area, such as destruction of farmlands, destruction of buildings, lives and properties.. Several threats to livelihoods ranging from the physical threats to social and economic threats exist. It is to this the study centres on Impact Of River Erosion On Physical Landscape In Itigidi Abi Lga Cross River State

1.3 OBJECTIVES OF THE STUDY

The major aim of the study is to examine Impact Of River Erosion On Physical Landscape In Itigidi Abi Lga Cross River State. Other specific objectives of the study include;

1 To examine the types of Erosion obtainable in in Itigidi Abi L.G.A

2 To outline the factors influencing river erosion on Land in Itigidi Abi Lga Cross River State

3 To examine the impact of river erosion on land in Itigidi Abi Lga Cross River State

4 To outline preventive measures for the control of erosion in the study area

1.4 RESEARCH QUESTIONS

1 What are the types of Erosion obtainable in in Itigidi Abi L.G.A?

2 What are the factors influencing river erosion on Land in Itigidi Abi Lga Cross River State?

3 what is  the impact of river erosion on land in Itigidi Abi Lga Cross River State?

4 What are the preventive measures for the control of erosion in the study area?

1.5 HYPOTHESIS

HO1: there is no significant impact of river erosion on the physical landscape in itigidi abi lga cross river state

1.6 SIGNIFICANCE OF THE STUDY

Therefore, the present research study is required to comprehend . This study concentrated on River Erosion. Researchers will benefit from this study, which will act as a springboard for additional investigation and provide useful reference material for students who may want to utilise the research's findings. The three tiers of the government will also use this study as a baseline survey for developing disaster management strategies and for advancing knowledge.

1.7 SCOPE AND LIMITATION

This study was limited Impact Of River Erosion On Physical Landscape In Itigidi Abi Lga Cross River State.. As such, the boundary of this study is limited to Itigidi Abi Lga Cross River State

1.8 DEFINITION OF TERMS

ENVIRONMENT: The natural environment or natural world encompasses all living and non-living things occurring naturally, meaning in this case not artificial. The term is most often applied to the Earth or some parts of Earth

RIVER EROSION: Many rivers erode their banks and bed as they flow, slowly breaking down pieces of sediment and transporting them as time goes on. This process wears away the beds and banks of rivers, and can even change the shape of a river over many years.

PHYSICAL LAND SCAPE; Physical geography is one of the three main branches of geography. Physical geography is the branch of natural science which deals with the processes and patterns in the natural environment such as the atmosphere, hydrosphere, biosphere, and geosphere

1.9 ORGANIZATION OF THE STUDY

The study will be divided into five chapters. The first chapter will contain the introduction, back ground to the study, statement of the research problem, research questions, and objectives of the study, and significance of the study, scope of the study, definition of terms and organization of the study. The second chapter will deal with relevant studies found in the literature and that are related to the study which includes the conceptual discourse, review of studies and theoretical framework of the study. The third chapter will center on research methodology. Fourth chapter will deal with the analysis On the topic and Finally, chapters five will contain the summary, conclusions and recommendations which are derived from this study.