Complete Material Cost #3,000

Order for Complete Material now

ABSTRACT

Sediments represents essential element of most aquatic ecosystem. This work is aimed at studying the physical and chemical characteristics of sediment in Andoni river intertidal mudflats. Three stations were chosen along the length of the river and samples were collected using a hand-held trowel by digging deep into the substratum to collect samples. Sediment textural class was determined by the Bouyoucous hydrometer method, pH and conductivity were determined using the electronic pH meter and conductivity meter respectively. Nitrate, phosphate, sulphate and Total Hydrocarbon Content (THC) were determined by UV Spectrophotometric method while Total Organic Carbon (TOC) was determined by acid titration method. The particle size of sediment ranged from sand to silt across the three stations with a mean of 87.55%, 10.78% and 1.67% for sand, clay and silt respectively. pH (5.59), conductivity (23,266.6 µS/cm), nitrate (2.5 mg/kg), sulphate (1,121.6 mg/kg), phosphate (2.2 mg/kg), TOC (1.638%) and THC (3.39 mg/kg). The eutrophic condition of the river if not closely monitored and controlled can cause severe ecological harm to the water body. Activities aimed at restoring the natural state and functioning of the Andoni river in support of biodiversity, recreation, flood management and landscape development is strongly recommended.

TABLE OF CONTENTS

COVER PAGE i

DECLARATION i

CERTIFICATION ii

DEDICATION iii

ACKNOWLEDGEMENT iv

ABSTRACT v

TABLE OF CONTENTS vi

CHAPTER ONE: INTRODUCTION 1

1.1 BACKGROUND OF STUDY 1

1.2 STATEMENT OF THE PROBLEM 5

1.3 AIMS OF THE STUDY 6

1.4 SIGNIFICANCE OF THE STUDY 7

1.5 SCOPE OF THE STUDY 7

1.6 DEFINITION OF KEY WORDS 7

CHAPTER TWO: LITERATURE REVIEW 9

CHAPTER THREE: MATERIALS AND METHOD 23

3.1 STUDY AREA 23

3.2 SAMPLE COLLECTION 27

3.3 SEDIMENT SAMPLE PREPARATION AND ANALYSES 28

CHAPTER FOUR: RESULTS AND DISCUSSION 32

4.1 RESULTS. 32

4.2 DISCUSSION 37

CHAPTER FIVE: CONCLUSION AND RECOMMENDATIONS 51

5.1 CONCLUSION 51

5.2 RECOMMENDATIONS 51

REFERENCES 53

CHAPTER ONE

INTRODUCTION

1.1 BACKGROUND OF STUDY

Intertidal mudflats are prominent sub-environment found on the fringe of estuaries and in low relief sheltered coastal environments. The fine grained sediments of the intertidal mudflats (70-90%) are derived from terrestrial and marine regions. Mudflats act as a major sink for trace metals, metals which are discharged into aquatic environments from various sources may admix or interact with fine suspended sediments and are subsequently removed from the water column thus facilitating deposition in the intertidal regions leading to trapping of contaminants into estuaries (Reineck et al., 1980).

Tidal flats lie between the land and the sea, characteristics of regular alternations of exposure and flooding by tides. They are valuable for coastal-wetland biodiversity, conservation and buffer zone to accommodate rising sea level and more and stronger rough seas due to global change. However, these lands are under increasing pressure from coastal erosion and land reclamation with the latter, the primary way that our ancestors conquered the sea for hundreds to thousands of years.

Mudflats may be viewed geologically as exposed layers of bay mud resulting from deposition of estuarine silts, clays and marine animal detritus. Most of the sediment within a mudflat is within the intertidal zone and thus the flat is submerged and exposed approximately twice daily. Intertidal areas are highly dynamic systems which are constantly influenced by local energy levels and especially in the case of high energy, sand flat areas exhibit a micro-structure which is governed by repeated erosion and deposition during the networking of the sediment (Swart, 1983).

Mudflats also known as tidal flats are un-vegetated areas, consisting of mud, sand and /or gravel and are regularly exposed and flooded by the tides. They exist in sheltered areas with low wave-action, inlet/and estuaries and are formed by the deposition of fine sediments that have been suspended in the sea or estuary. Mudflats provide important habitat for bottom-dwelling invertebrates such as clams and mussels, and thus provide food for predatory fish, birds and invertebrates such as the horseshoe crab, mudsnail and shellfish species (Anthony and Orford, 2002).

Changes in water patterns from development may increase or decrease water flow. Contaminants such as heavy metals, hydrocarbon, wastewaters and storm waters can add to water quality degradation. A common characteristic of almost all intertidal mudflats is the high production. This fact makes them attractive breeding, nesting, over wintering and migration stopover grounds for birds and as nursery ground for many fish species (Davis and Dalrymple, 2011).

Pressure on estuaries increases as population number grows and development increase both in catchments and coastal areas. Intertidal flats and their associated communities are highly susceptible to changes in land use and other activities in catchments. Mining, urban and industrial activities can cause input of trace elements and organic compound into estuaries which may be stored in sediment (Edun et al., 2012).

The sediments then become a potential source of trace elements and organic compounds to animals and plants both in the sediment and the overlaying water. The natural release of trace elements and organic compounds from sediments depends upon the relative levels of the trace elements and organic compounds in the sediment and the water (Odokuma and Ijeoma, 2003).

Humans, as a final link in the food chain are always mostly affected, and consequently the public has become the potential risk to human health when consuming such polluted biota (Bhattacharya et al., 2015). Conversely, benthic organisms (like gastropod, fish and crab) can be used to monitor the quality of aquatic ecosystem with broad geographical distribution, fixed lifestyle, easiness of capture, and the promotion of bioturbation (Cantillo et al., 1997, Yang and Si, 2016 and Nordhans, 2006).

The granulometric and mass properties of lake and marine mud are similar, although lacustrine sediments at a given depth are typically finer grained than marine sediments because of lack of tidal current and higher sedimentation rates.

Excess nutrients especially phosphates, sulphates and nitrates are classified as pollutants in waste water. Exception of sulphates, the bedrock of the Niger Delta drainage basin is not essentially rich in phosphate and nitrates (Ezekiel et al., 2011).

Although several studies have focused on trace metal distribution in benthic organisms, little is known about the sediment physical and chemical characteristics from the Andoni River in the Niger Delta area of Nigeria. This study will bridge a gap in that respect, facilitate the management of the water and similar water bodies as well as provide baseline data for further studies.

1.2 STATEMENT OF THE PROBLEM

Human health, agricultural development and the ecosystem are all at risk unless water and land systems are effectively managed. Anthropogenic pollutants are sources of persistent toxic metal contaminants in the ocean (Lakshmanan et al., 2009). Industrial activities such as mining, electroplating, tanning, metallurgical operation, hydrocarbon exploration and exploitation, energy and fuel production, intensive agriculture and sludge dumping have led to the release of persistent toxic chemical compounds into aquatic environment.

Hence the analysis of sediment physical and chemical characteristics of the intertidal mudflat of the Andoni River is key to making the populace aware of the devastating effects of the aforementioned practices on the ecological balance of the recipient environment and a diversity of aquatic organisms.

1.3 AIMS OF THE STUDY

This study is aimed at analyzing sediment physical and chemical properties of intertidal mudflats of the Andoni River. Specifically, the objectives are:

i To determine the particle size of the sediment in Andoni River intertidal mudflats.

ii. To determine the chemical content of the sediment.

iii To proffer management strategies geared towards the conservation and protection of the environment.

1.4 SIGNIFICANCE OF THE STUDY

Sediment analysis is important in evaluating qualities of aquatic ecosystems because it reflects the long term quality situation. In recent times, environmentalists and regulatory agencies are increasingly interested in sediment quality. The present study sediment physical and chemical analysis of the Andoni River intertidal mudflat will provide baseline information which could be used by research institutions, scholars, scientists as well as governmental agencies as a reference in time of impact.

1.5 SCOPE OF THE STUDY

The extent of work to be carried out has been confined to the sediment physical and chemical characteristics of the Andoni River intertidal mudflats.

1.6 DEFINITION OF KEY WORDS

ANTHROPOGENIC: Relates to or results from the activities or influence of human beings on nature or the environment.

COASTAL: A geographical location or region where interaction of the sea and land processes occurs.

ESTUARY: A partially enclosed coastal water body where fresh water from river and streams mixes with salt water from the ocean.

FLUVIAL: The physical interaction of flowing water and the natural channels of rivers and streams and the deposits and landforms created by them.

INTERTIDAL ZONE: This is the area that is above water at low tide and under water at high tide.

MUDFLATS: These are coastal wetlands that form when mud is deposited by tides or rivers.

RIVER: A natural flowing water course usually freshwater flowing towards an ocean, sea, lake or another river.

SEDIMENT: This is a naturally occurring material that is broken down by processes of weathering and erosion and is subsequently transported by action of wind, water or ice and/or by the force of gravity acting on the particles.

SEDIMENT PHYSICOCHEMICAL CHARACTERISTICS OF ANDONI RIVER INTERTIDAL MUDFLATS