CHAPTER ONE

INTRODUCTION

This chapter presents the background of the study, statement of the research problem and other preliminary information. The research problems will be outline, from which the research questions will be generated leading to the objectives and hypotheses. The chapter also presents justification of the study and delimitation. The scope and delimitation of the study will be divided under thematic, temporal and spatial delimitation where the study area will be located with it various characteristic and this chapter will round up with a chapter synthesis.

1.1 Research Context

Coastal ecosystems, particularly coastal estuaries and lagoons, are renowned for high productivity, providing approximately 30% of the total primary production and biodiversity in the world’s marine systems (Alongi, 2020). These areas encompass dynamic physical and biological interactions between material inputs from Stream as well as oceans, and these interactions underpin much of their ecological value and function (Hobbie, 2020). Streams provide many benefits to society, including providing habitats for key economic species, sources of food, transportation and recreation for humans. Stream also play an invaluable role in supporting key biogeochemical cycles, trophic energy flow, and stock recruitment in the marine environment (Wilson, 2013), much of which underpins the ecological services that humans depend upon. However, Stream are under increasing pressure due to human activities, which alters the characteristics, capacities and processes within these ecosystems. Continued rapid growth of human populations in and adjacent to Stream has led to significant impacts including: Nutrient enrichment in Stream and estuaries underpinning harmful algal blooms and oxygen depletion or hypoxia; degradation and loss of coastal habitats such as salt marshes, mangroves, seagrass; alteration of natural hydrological flows due to landscape design or damming of Stream, leading to changes in the magnitude and seasonal patterns of freshwater and sediment inputs into estuaries; declines in fish and wildlife populations due to overexploitation and habitat destruction; pollution by toxic materials including both organic (PCBs & PAHs) and inorganic contaminants (heavy metals) as well as nutrients being discharged into estuaries by industrialization and agriculture; and biodiversity loss and habitat deterioration by exotic species introduced into estuaries (Bianchi, 2017, Hobbie, 2020).

Rapid and progressive urbanization and significant anthropogenic alterations of the natural landscape have become an inevitable threat to almost every physical habitat of living organisms since the second half of the twentieth century. Among them, the Stream landscapes are one of the most exploited, altered, and mismanaged by human activities, because of their massive resource potency regarding water, sediments, and living biota (Bandyopadhyay & De, 2016; Zope et al., 2016). Most foothill regions in the world are experiencing rapid land-use transformation over the last few decades resulting in the decay of several Stream such as Mahananda, Balason, Sahu, Rakti, Panchanai, Dharala, and Karala. Stream have always been a reliable source for human communities. They have been a preferable place for settlements in early history and still provide a rich environment for big cities (Allan and Flecker, 2019).

In the developed world, protected areas are separated in two types (Basil, 2000): The Strict Protection Area, which has the purpose of nature conservation, without direct use of its resources; and the Sustainable Use Area, which must reconcile conservation and sustainable use of natural resources. São Paulo state has the largest continuous area of Strict Protection Area of Atlantic Rain Forest, formed by the Serra do Mar State Park. Created in 1977 with educational, recreational and scientific purposes (São Paulo, 2006), it currently comprises an area of 3,326.8 km and is divided into nine units, each with its own manager, (Ngidang et al. 2014). The Serra do Mar State Park protects a number of small streams that run entirely within the protected area, but also receives some watercourses that rise upstream, outside its boundaries, which can be subjected to the impacts of human activities. That is the case of the Paraibuna Stream that has its headwaters located upstream of the Cunha unit, outside the protected area. In this region there are small farms, with animal husbandry (chicken, cattle, sheep, trout), agriculture and eucalyptus plantations (Porter et al. 2013). Moreover, along its course, the stream that drain into the Paraibuna Stream have their margins subjected to cattle trampling, which is facilitated by the absence of riparian vegetation and also prevents its natural regeneration process. There are also impacts associated to the existence of rural roads bordering the Paraibuna Stream or its tributaries that are used as an access to neighborhoods and to the park itself (Wooten 2013).

The Songhua Stream Basin (SRB) is one of China’s seven major basins, with a population of approximately 60 million. The SRB is an important base for industry and food production in China because of its abundant resources and fertile land. The strategy Revitalizing the Northeast Old Industrial Base has put forward a long-term plan for the whole basin, which identified that maintenance of the basin’s ecological security will preserve food security and water resource in the northern part of China (Hobbie, 2010). The goal of this study was to assess the spatial human threat to the SRB, as well as to discuss the impact of each factor on the result of the integrated assessment. The ecological threats posed to the current water quality or species distribution also demanded analysis to enhance the ability of water resource conservation and watershed management (Bianchi, 2017).

The suspended sediment load of a Stream represents a key component of its hydrology, and in turn exerts an important influence on its aquatic ecology, its morphology and the exploitation of its water resources. Changes in the sediment loads of Stream can therefore have wide-ranging environmental and social and economic implications. There is clear evidence that increased fine sediment loads can cause major problems in degrading aquatic habitats (Dudgeon, 2012), but it is also important to recognise that fine fluvial sediment can provide an essential source of nutrients in some aquatic systems, including those supporting large fisheries, as well as in coastal waters where fine fluvial sediment may represent an important source of nutrients to both marine biota, coastal water resourcess and mangrove stands. Reduced sediment loads may therefore also have negative environmental impacts. Sediment transport and the magnitude of the sediment load also play a key role in the dynamics of Stream channels (Horton, 2013). Although the coarser fractions of the sediment load are generally more important in this context, fine sediment may also exert a significant control on Stream morphology in some Stream systems. Deltas can also be considered to be an integral part of the fluvial system. Such areas are highly dependent on a continuing supply of sediment, and particularly fine sediment, for their continued evolution and stability (Andrew et al., 2009). As depositional sinks, deltas are commonly areas of subsidence and an input of sediment is required to balance such subsidence and maintain the delta. Reductions in sediment load can therefore have important implications for delta evolution (Syvitski et al., 2009). High or increasing sediment loads can also pose major problems for water resource development, particularly in terms of loss of reservoir storage due to sedimentation and siltation of water distribution systems (Basson, 2008).

Most countries in Africa, the effects of disposing untreated sewage in aquatic systems cause depletion of Dissolved Oxygen (DO) due to oxidation of organic matter and increases nutrients such as nitrogen and phosphorus. Alien invasive species like the water hyacinth, also causes a reduction in Dissolved Oxygen (DO) and light levels in water, is a major threat in Manyame Stream (Masundire and Mackay, 2002). The water hyacinth weed has caused a decline in fish catches in Lake Chivero. The water hyacinth can also increase evaporative water losses from reservoirs and water bodies by as much as 3.5 times (Davies and Day, 1998), representing an enormous economic loss, in terms of water available for economic production for example irrigation. Water quality degradation is one of the most serious of all environmental problems because it can affect human health and economic activities as well as biotic communities (Turpie and van Zyl, 2002). With population growth and economic growth in the Manyame Catchment, surface and groundwater quality is increasingly being degraded by industrial and agricultural activities, and domestic sewage. Mukuvisi Stream which runs into Harare’s drinking water supply was found by Chenje and Johnson (1996) to contain high concentrations of nutrients, sulphates, calcium, magnesium, fluoride, aluminium and iron largely from industrial dumps along the Stream banks. 

There has been high incidence of waterborne diseases in areas of Chitungwiza and Norton as a result of untreated sewage finding its way into drinking water sources. This, in turn, was caused by overburdening of the sewage systems as a result of the ever increasing volume of wastewater generated by an increase in the population of Harare (Moyo and Mtetwa, 2002), whilst the sewage treatment facilities are not increasing at the same rate. The population of Harare, according to the 2002 national census was 1,444,534 and Chitungwiza had a population of 321,782 (CSO, 2003). The Firle Sewage Works treats half of Harare’s sewage and was designed to treat 72,000 m3 of wastewater, but now the plant receives flow in excess of 100,000 m of wastewater per day (Moyo and Mtetwa, 2002). 

Human activities change the ecosystem processes, composition, and structure at multiple spatial scales, making evaluation of ecological security more complicated. Thus, during the evaluation process, it is critical to assess the severity of stresses on ecosystem integrity. Ecological security assessment is the identification and judgment of ecosystem integrity and sustainability to maintain ecosystem health under all kinds of risks, and it offers a means to compare and weigh the threats posed by human disturbance (Hoey and Bellwood, 2009). Evaluation of ecological threats at large scales can improve the conservation efficiency for watersheds and enhance the management capacity of administrators, thus playing a positive role in integrated management of the watersheds. Many scholars have endeavoured to advance such evaluations and have made some progress (Edgar et al., 2010).

 Mattson and Angermeier (2011) proposed the Ecological Risk Index Protocol to quantify 12 threats of the upper Tennessee Stream Basin based on human impacts and ecological integrity. Falcone et al.  qualified 33 potential disturbance factors generated from available GIS data, which was applied to the Western United States. (Vörösmarty et al 2014). selected 23 factors from four themes to diagnose threats over worldwide fresh water from both human water security and biodiversity perspectives by the method of expert assessing. Further, by comparing studies on ecological security and risk assessments that were applied at various spatial scales, it has been demonstrated that data acquisition and analytical methods vary, and one approach does not appear to be more advantageous than another.

Urbanization in Cameroon has led to an encroachment into the coastal and marine to the inland freshwater lakes, dams, Stream and swamps. Cameroon having an agricultural based economy has majority of her population deriving their livelihood from various forms of agriculture. Stream in their natural state are dynamic ecosystems that perform many beneficial functions. Natural stream and their flood plains convey water and sediment, temporarily store excess flood water, filter and entrap sediment and pollutants in overbank areas, recharge and discharge groundwater, naturally purify instream flows, and provide supportive habitat for diverse plant and animal species (Maidment,et al., 2004). The stream corridors wherein these beneficial functions occur give definition to the land and offer “riverscapes” with aesthetic qualities that are attractive to people. Human activities that impact stream ecosystems can and often do cause problems by impairing stream functions and beneficial uses of the resource. Solving stream management problems requires knowledge and understanding of the stream’s natural processes, and since many problems originate beyond the banks, a watershed approach (Dunne and Leopold, 2010). However, rapid increase in human population and the consequent intensive
agriculture, urbanization and industrialization, have not only increased the demand for water
but also impacted directly upon the rivers. Rivers have been tamed, amputated, abused and
treated with utmost contempt. First, the river flows were diverted or held behind dams,
leaving the downstream reaches dry(Chacko and Ganapati 2011) . Riparian vegetation was totally removed, and human settlements and agriculture encroached upon the floodplain. Soon, the river courses were channelized by creating embankments in name of flood control. All kinds of domestic and industrial wastes were discharged, mostly without any treatment, into the rivers. Lately, the riverbanks have become landfill sites for dumping all kinds of solid wastes. Even the dry riverbeds are cultivated with indiscriminate use of organic wastes and agrochemicals. The consequences of such human abuse of rivers were felt long ago in the form of declining fisheries and other wildlife, frequent floods, and degradation of water quality (Jhingran. 2008).

The Urban residents of Bamenda city are the main users of Stream banks and water site either for building, agricultural purposes or as areas of waste disposal due to the rapid rate of urban growth and the high cost of naturally drained areas. This has created a situation whereby during the pick of the rainy season, flooding may result in both losses of lives and properties. Several developments have taken place in the Stream Channels in Bamenda city including settlement, business structures, workshops, schools and agricultural activities as well as serves as waste disposal sites (Le et al., 2015). For several years, the water bodies and Stream channels in Bamenda city has undergone massive exploitation which is resulting into so many implications, the exploitation of Stream channels in Bamenda city has led to the flood, deviate course and migration of an ecosystem of certain species of flora and fauna, as these species are forced to dieback. It has equally led to over flooding in Bamenda city especially around Futru, Mile 4, Sisia quarter and Mile 3, where crops and houses are being swept by heavy rains due to poor drainage. The Stream Channels in Bamenda city has become a dumping place for the settlers as waste is being disposed there all the time (Luu et al., 2012).

1.2. Problem Statement

The city of Bamenda is a host of so any social, economic and environmental amenities that has resulted to rural-urban migration. This has led to the increase in population of Bamenda with inadequate land available for the dweller to settle or carryout their activities. The major streams channels are one of the most dynamic features of the landscape, being subjected to regimes of disturbance and change. Major streams channels in Bamenda city has evolved to cope with the stresses associated with such regimes. These streams have been managed poorly in the past throughout the existence. Various human activities have caused much indigenous vegetation to be cleared from stream banks and floodplains for ‘improvements’ associated with agricultural production, urbanization, irrigation, river navigation, flood mitigation and river engineering.  The widespread disturbance of streams channels has compromised the genetic and ecological integrity of many species and communities of around the streams and has contributed to detrimental impacts on the in-stream ecology and geomorphology of many rivers. In addition, many exotic species of vegetation have been planted in the zone, particularly in the streams like mile 4, mobile and up sisia, resulting in major detrimental impacts, both genetically and ecologically, on the streams channels

Also, the rapid and unplanned urban growth of Bamenda due to the natural increase as well as the high rate of in-migration into Bamenda town has made it difficult for the council authorities to collect waste and to control settlement expansion along stream channels. These waste block gutters, culverts and stream channels thereby increasing the occurrence of flood hazards in the major stream channels and the pollution of the stream environment. The exploitation of stream in Bamenda has led to the lost, extinction and migration of an ecosystem of certain species of flora and fauna, as these species are forced to dieback. It has equally led to over flooding in Bamenda especially around Futru, Mile 4, Sisia quarter and Mile 3, and mile 6 Nkwen where crops and houses are being swept by heavy rains due to poor drainage. The major streams in Bamenda have become a dumping place for the settlers as waste is being disposed there all the time. Because of this, the streams that act as water filters do not filter water again. Human activities such as bars and hotel also dump waste in these stream channels such as mile four stream where the bars and restaurant operating around dump waste bottles and plastic waste into the river which deviate the stream and causes flood and other lost and lastly washing point which has been set up along most river channels like city chemist areas, Old town also cause impact along these stream channels. This has resulted to the destruction of Stream banks and deviate Stream channel, environment and ecosystems as well as increased frequency of flooding, irrational use of land leading to soil loss.

Therefore, there is the problem of designing a comprehensive exploitation plan of the Stream and its banks that will be accepted by all. It is in the face of these difficulties that the study seeks to assess the human interference along major Stream channels and its implication in Bamenda City. It is in the face of these difficulties that the study seeks to assess the implication of human interferences along major streams channels in the Bamenda city, North West of Cameroon.

1.3 Main Research Question

What are the implications of human interference along major Stream channels in Bamenda city?

1.3.1 Specific research questions

1. What are types of human activities along stream channels in Bamenda?
2. What are the implications of human interference along Stream channels in Bamenda?
3. What is the mitigating measure to conserve or protect stream channels from human interference in Bamenda?

1.4. Main Research Objective

To investigate the implications of human interferences along major Stream channels in Bamenda city

1.4.1 Specific research objectives

1. To identify the types of human activities along stream channels in Bamenda
2. To assess the implications of human interference along Stream channels in Bamenda
3. To bring out the mitigating measure to conserve or protect stream channels from human interference in Bamenda