Evaluation of Development Dynamics of Awka Capital Territory, Anambra State, Using Remote Sensing Igbokwe, E.C1, Emengini, E
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ISSN XXXX XXXX © 2019 IJESC Research Article Volume 9 Issue No.4 Evaluation of Development Dynamics of Awka Capital Territory, Anambra State, using Remote Sensing Igbokwe, E.C1, Emengini, E. J2, Ojiako, J.C3 Department of Surveying and Geoinformatics Nnamdi Azikiwe University Awka, Nigeria Abstract: This study investigated the development dynamics of Awka Capital Territory in Anambra State, Nigeria using Remote Sensing. The objectives were to: examine the spatial extent of land cover and land use in Awka Capital Territory for the last 27 years (1990 – 2017); ascertain the trend of change, transition and pattern of the land cover/land use classes during this period and predict the future urban development dynamics for the next 30 years (2018 – 2048). The results revealed that urban area grew from 27.92% to 31.19%, to an of area of 14437.68 hectares between 1990 and 1999, 31.19% to 33.67%, to an area of 15586.73 hectares between 1999 and 2008, and 33.67% to 37.24%, to an area of 17237.45 hectares between 2008 and 2017. Trend of change analysis indicated that urban area had an annual rate of change of 0.62% between 1990 and 1999, 0.43% between 1999 and 2008 and 0.56% between 2008 and 2017. Transition results showed that between 1990 and 1999, urban area gained 1272.73 hectares from vegetation and 242.5 hectares from open space, also between 1999 and 2008 urban area gained 1000 hectares from vegetation and 149.05 hectares from open space, in the last epoch between 2008 and 2017 urban area gained 1068.27 hectares from vegetation, 582.45 hectares from open space. The study revealed two patterns inherent in the study area: edge-expansion and infilling, with edge-expansion being the most dominant growth pattern in the study area between 1990 and 2017, there was no evidence of spontaneous pattern of growth within the study area. Prediction of the future urban development dynamics of Awka Capital Territory in 2048 revealed that urban areas is expected to increase from 35.45% to 49.41% i.e. from area coverage of 17798.44 hectares to 22871.51 hectares. It was recommended that the approach be used as tool for planning and decision making in urban development. Keywords: Development Dynamics, Growth Pattern, Remote Sensing, Trend Analysis, Urban Growth. 1.0. INTRODUCTION landuse and landcover changes. There has been a migration from rural to urban areas, resulting in the territory becoming a highly Previous studies have shown that there remain only few urbanized with 62% of its population living in urban areas (UN- landscapes on the Earth that is still in their natural state HABITAT, 2009). The shift in urban migration has (Opeyemiet al, 2015; Kumar et al, 2007). Due to man’s posed problems for Awka Capital Territory, infrastructure activities, the landscape is being altered and man’s use of land improvements, both physical and social, has lagged behind the has had a profound effect upon the environment thus resulting growth in population. There are problems in erosion, flooding into an accelerated expansion (Zubair, 2008). Urban expansion is due to unregulated building patterns, poor sanitation, noise and dynamic and constantly changing with man’s changing social air pollution, and overcrowding. The available information on and economic needs and therefore require constant monitoring. the growth dynamics in the Awka Capital City is This is especially true in most developing countries including insufficient. This makes decision making process complex and Nigeria where proper and periodic monitoring of urban less transparent, deeper understanding of the mechanisms expansion is not carried out (Opeyemiet al, 2015). Urbanization underlying the urban dynamics can assist toward formulating is among the most significant process that has shaped landuse appropriate policies of urban growth management, and thus, activities and has drawn a great deal of attention throughout the lessening the negative impacts of urbanization while maximizing world (United Nations, 2017). It is estimated that urban the positive impacts. Thus, in order to understand the dynamic population will rise from 3.57 billion in 2010 to 6.34 billion in process of urban spatial growth, researchers throughout the 2050 where almost 70 percent of the world’s population is world have implemented diverse approaches, where spatial expected to live in the cities (United Nations, 2017). This models have been developed to study, predict and simulate immense figure is mainly due to migration from rural to city in future urban growth (Batty, 1994). To understand the dynamics search of better quality of life generated by urban activities and of growth in Awka Capital Territory, a broad analysis of the services (Deng et al, 2018). However, an increase of urban spatial trends of urban growth would help in addressing the population has forced cities to expand vertically or horizontally, needs of the present and future needs of the region. This plays a encroaching into agricultural land and natural boundaries, and key role in planning for infrastructure and becomes crucial in changing landuse and landcover without us realizing it (Suet al, planning especially when resources are scarce. Remote Sensing 2017). Awka Capital Territory is no exception; Awka Capital is an effective tool for analyzing urban development in Awka Territory is rapidly developing into a mass of urban areas Capital Territory. The collection of remotely sensed data growing to merge with each other which has caused spatial facilitates the synoptic analyses of Awka Capital Territory over International Journal of Engineering Science and Computing, April 2019 21719 http://ijesc.org/ time; such data also provide an important link between intensive, particularly in the urban area and also to ascertain the trend and localized ecological research and regional, national and characteristics of the growth dynamics in the last 27 years so as international conservation and management of biological to predict possible changes that might take place in this status in diversity (Wilkie and Finn, 1996). With the collection of these the next 30 years. spatial and statistical data for a different time period, it is then possible to monitor, manage urban growth and also predict what 2.0 STUDY AREA future urban growth would look like.The combination of remotely sensed data and Molusce algorithm in this research Awka Capital Territory is located in Anambra State, South provides a detailed insight into the spatial extents of landcover Eastern Nigeria (See fig. 2.0). It is located between latitude 60 5’ /landuse with emphasis on urban growth of Awka Capital N and 60 15’ N and longitudes 70 0’ E and 7o 5’ E. Awka capital Territory, in the past, present and also the future. Therefore, this territory covers a land mass of 400 square kilometres and research investigated and analyzed the status of development comprises of six local government areas namely Anaocha. Awka dynamics of Awka capital territory between 1990 and 2017 with North, Awka South, Dunukofia, Njikoka and Orumba North, in a view to detecting the change dynamics that has taken place part or full (UN-HABITAT, 2009). Figure 2.0: Map of Study area 3.0 MATERIALS AND METHOD the accuracy of classification of images. Random sampling technique was used to determine the location of the points. The 3.1 Materials spectral bands were then stacked to produce a color composite of The data that was used in this research were Landsat 5 Thematic the study area for each year (1990, 1999, 2008, 2017 and 2018), Mapper for the year 1990, Landsat 7 Enhanced Thematic after which land cover maps of the study area were produced Mapper for 1999 and 2008, Landsat 8 Operational Land Imager using the supervised maximum like lihood classification for 2017 and Sentinel-2 for 2018, all obtained from algorithm in ERDAS Imagine used by (Onojeghuo and www.earthexplorer.usgs.gov. Other ancillary data used were Onojeghuo,2013). In order to ascertain the trend of change and boundary map of Awka Capital Territory, transportation data of transition of the landcover/landuse classes in the last 27 years, Awka Capital Territory and population data of Awka Capital the results obtained from the landcover/landuse classification Territory. statistics table were used to compute trend analysis as adopted from long et al (2007). The comparison of the landcover/landuse 3.2 Method statistics assisted in identifying the annual rate of change The thematic map per for the year 1990, enhanced thematic between 1990 and 2017. In achieving this, table was prepared mapper for 1999 and 2008, operational land imager for 2017 and showing the areas and percentage change for each year measured sentinel-2 for 2018 were radio metrically and geometrically against each other. To determine the rate of change of corrected as used in (Orimoloye et al, 2018), after which level landcover/landuse, the year period 1990-2017 was divided into one classification scheme was developed for the study area after three sub-periods 1990 – 1999, 1999 – 2008 and 2008 - 2017 (Anderson et al, 1967),this resulted in the following class and compared against each other. A quantitative method by features: urban area, water body, vegetation and open space. Zenget al, (2010) was also used to distinguish three urban Ground truthing was carried out to collect sample data for growth types: infilling, edge expansion, and spontaneous growth accuracy assessment, forth is purpose, the coordinates of 256 in the study area. The dominance of each growth types is selected ground control points was collected and used to assess meaningful to describe the process of landscape pattern changes International Journal of Engineering Science and Computing, April 2019 21720 http://ijesc.org/ between two or more time points. The landcover maps of 1990, 31.19 %, to area of 14437.68 hectares.