Surveying and Geoinformatics- Conference Papers

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    Open Access
    The application of remote sensing and GIS technology to erosion risk mapping
    (Multidisciplinary Digital Publishing Institute, 2018) Makinde, E. O.; Oyebanji, E. I.
    Erosion is one of the major problems in Nigeria and Lagos State in particular. The objectives of this research are to identify land use/land cover changes in Eti-Osa LGA and estimate actual erosion risk using Revised Universal Soil Loss Equation (RUSLE) model. In addition, this research evaluates the perception of communities within the study area with the view of understanding the risk involved in erosion. The result showed that the sediment yield of the study was estimated to be between 0 to 48 ton/ha/yr. The estimated soil losses were higher at Eti-Osa West, parts of Iru/Victoria Island, and Ikoyi/Obalende areas recorded low losses. Land uses mostly affected by very high and severe erosion are the bare soils and the crop lands having about 3% to 4% respectively compared to the others. It was concluded that combination of rainfall, lack of cover for the surface soil, were the major causes of soil loss in the study area.
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    Open Access
    An Assessment of the spectra characteristics of vegetation in south western Nigeria.
    (IERI Procedia, 2014) Omodanisi, E. O.; Salami, A. T.
    This study assessed the status of oil spill induced stress in the vegetation in Lagos and Ogun States, in the South West of Nigeria. The locations of oil spill impacted areas were identified on the field using information from the locals and a Global Positioning System with an accuracy of ± 5m and subsequently identified on the 5 m resolution RapidEye satellite image of 2009 and 2011. Field spectra were collected using Analytical Spectral Device (ASD) Handheld2 Spectrometer. The results showed varying spectral measurement of the impacted and the control. Indices were then used to distinguish less stressed from stressed vegetation which were statistically higher at F-ratio 4.825 (p < 0.01) and 3.194 (p < 0.01) in Lagos State; and 4.564 (p < 0.01) and 2.731 (p < 0.1) in Ogun State. It was concluded that oil spill had changed the spectra characteristics of impacted vegetation.
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    Open Access
    Establishment of an empirical geoid model for a small geographic area: A case study of Port Harcourt, Nigeria.
    (Surveying and Land Information Science, 2010) Olaleye, J. B.; Aleem, K. F.; Olusina, J. O.; Abiodun, O. E.
    This paper examines changes in land-use and land-cover pattern in Ilorin Emirate in Nigeria between 1986 and 2006. Landsat images of Ilorin Emirates at three epochs (1986, 2000 and 2006) were used. An administrative map of local governments in Kwara State and a land-use map of Ilorin were used as base maps. Global Mapper Software was used for the image enhancement; image classification was done with environment for visualizing images (ENVI) software and was later exported to the ArcGIS for further processing and analysis. The land consumption rate and land absorption coefficient was determined to aid the quantitative assessment of change. Subsequently, an attempt was made at projecting the observed land-use / land-cover for a period of 14 years ending at 2020. The result of the work shows a gradual growth in built-up land between 1986 and 2000 and this tends to grow more rapidly between 2000 and 2006. It was also observed that the change by 2020 may likely follow the trend observed in 2000 and 2006. It is recommended that the information from the results of this work should be use to optimally and effectively plan and manage the study area.
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    Open Access
    Land Use Change Analyses in Lagos State From 1984 to 2005
    (Proceedings FIG Working Week, 2011) Abiodun, O. E.; Olaleye, J. B.; Dokai, A. N.; Odunaiya, A. K.
    The physical development in an urban community and the need to control such development for economic, socio-political and environmental reasons have necessitated the requirement for geographical and statistical information relating to the amount of land that has been used and that which is remaining. Growth and physical expansion of urban settlements has occurred significantly all over the world. This growth in recent time has taken on more dramatic momentum in those areas that have come to be regarded as the “third world”. The most notorious example of urban growth in Nigeria has undoubtedly been Lagos. Lagos has become legendary for its congestion and other urban problems. Determination of this growth and knowledge of the rate of growth is essential for adequate future planning. In this work, we used ETM LandSat imagery (1984, 2001, and 2005), Lagos State administrative map, and Lagos State land use map (2007) to determine different land use uses in Lagos at different times. From this we obtain adequate information for the analysis of the changes in these areas over the years by overlapping series of classified satellite imageries. The changes observed for each year were analysed in a GIS environment. The result shows a change of other land use types to developed (built) land between 1984 and 2001. This pattern of change continued between 2001 and 2005. The result was discussed and recommendations were made on the impact of these observed changes in the local and global environment.
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    Open Access
    Land use change detection and analysis using remotely sensed data in Lekki Peninsula area of Lagos, Nigeria.
    (Proceedings FIG Working Week, 2009) Olaleye, J. B.; Abiodun, O. E.; Igbokwe, Q.
    Land use is generating worldwide interest as changes in land use are at a rapid rate and it is estimated by the United Nation's Population Fund (1999) that by the year 2025, 80% of the world's population will live in cities. Most major metropolitan areas face the growing problems of Land development; residential and commercial development is replacing undeveloped land at an unprecedented rate. Information on land in relation to how it is being used as well as changes in such land use has become a prime pre-requisite for the growth and development of any nation. Change detection involves the use of time series satellite imageries and orthophoto maps of the study area, from which Land use maps can be generated by visual interpretation or image processing. The use of remotely sensed data (satellite and aerial) to detect changes in Land use as well as precise and accurate analysis using GIS is widely preferred over other conventional survey techniques because the method is very efficient for assessing the change or degrading trends of a region. In this work, the changing pattern in Land use in Lekki Peninsula area of Lagos, Nigeria over the period of time spanning 39years is examined using a topographical map of 1964 and a Quick Bird image of 2003. A Land use map of the study area was produced using ArcGIS 9.2, which was used for the digitization and analysis. Evolution in new classes of Land use was observed. Industrial, Commercial and recreational Land use class were among the new classes of Land use present in 2003 as compared to the predominantly educational Land use class obtainable in 1964. The study also revealed a phenomenal rise in the area extent of built up areas from 40.93 hectares in 1964 to 7271.19 hectares in 2003. It is concluded that remote sensing and GIS tools provide an outstanding platform from which accurate information on Land use changes and patterns can be obtained and that Lekki Peninsula area of Lagos has experienced tremendous changes in land use in between 1964 and 2003, so, efforts should be made to regularly update available data in order to control further development.
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    Open Access
    The Perception of Communities Prone to Environmental Degradation
    (2nd Africa Regional Conference Technical Proceedings. Organization for Women in Science for the Developing World (OWSD) Organized under the Auspices of: University of Energy and Natural Resources (UENR), Sunyani, GHANA., 2014) Makinde, E. O.
    The activities of man affect the environment which in turn influences the climate. This study assesses these human activities by determining the perceived impact of oil spill and its attendant explosion and fire has on the environment. This study was carried out in Lagos, covering some coastal settlements in Amuwo-Odofin Local Government Area. Landsat 30 m (ETM+) of 2005 and Ikonos 10 m of 2007 were the satellite images used which were subjected to digital image processing and analysed. Also, the study area was divided into 3 strata and convenient sampling technique was used on each stratum to administer 200 copies of questionnaire for data collection which were analysed. The results showed that there was a decline in the high and light forested areas, respectively between 2005 and 2007. Furthermore, the result revealed that educational exposure affected the way the community perceived the impact of oil pipeline vandalization on the vegetation and strategies to prevent pipeline vandalization (F=2.8-5.9; p<0.05). It was concluded that oil pollution resulted in the reduction of vegetation while educational level affected the way in which the impact of the pollution was perceived.
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    Open Access
    Remote Sensing of Vegetation Stress and Indicators
    (Proceedings of Global Geospatial Conference 2013. Addis Ababa, ETHIOPIA, 2013) Makinde, E. O.; Salami, A. T.
    The study used spectra indicators to determine the health status of polluted vegetation. Global Positioning System with an accuracy of ± 5m were used to identified stress areas. The identified impacted areas were mapped out for the field and Multispectral satellite image (RapidEye, 2009 and 2011) study. Control plot was established in relatively unstressed area. Spectra measurements were taken using hyperspectral Analytical Spectral Device (ASD) Handheld2 Spectrometer within a field of view (FOV) of 25°. Spectral indicators were calculated and the relationship between these spectral indices and chlorophyll content of the vegetation were determined. The correlation coefficients of 0.5 and higher were observed in plot B and Plot C of Ogun. Plot C of Ogun of had a range of 0.6 -0.83 rho at p>0.01 for all the indices. The result of the Analysis of Variance identified the best ratio and vegetation indices that significantly differed between less stressed (control) and more stressed (impacted) plots. RedEdge indices had an F-ratio of 4.564 at p<0.01 and 2.731 at p<0.1 for VOG1. The image data analysis showed that there was a direct relationship between different pollution levels and the chlorophyll content of F-ratio 325.8 (p< 0.0001) and 93.36 (p < 0.001) for 2009 and 2011.The study concluded that vegetation impacted by oil spill pollution are unhealthy.
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    Open Access
    Remote Sensing, A Vital Tool in Monitoring Climate Change
    (Proceedings of the 2nd Annual Conference of the Institute of Ecology and Environmental Studies, Ile-Ife, OAU., 2009) Omodanisi, E. O.; Salami, A. T.
    The impact of anthropogenic activities on the planet we inhibit has affected the climate. Humans are at risk as the earth is warming up. It is through the observation of atmosphere and hydrosphere data; and by using the latest technology such as Remote Sensing (RS) and geographical Information System (GIS) that climate change could be monitored, assessed, analysed and interpreted effectively on real time basis. This paper highlights how RS and GIS can be adopted in combating climate change.
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    Open Access
    Spectral Indices for Detecting Change Trend in Vegetation affected by Hydrocarbon Spillage
    (International Proceedings of Chemical, Biological and Environmental Engineering (IPCBEE), Singapore, 2015) Makinde, E. O.
    Geo-informatics and in-situ technologies have made it possible to quickly assess, monitor and analyse vegetation biodiversity accurately in a non-destructive way. The goal of this study was to investigate the change trend based on the absorbance or reflectance of certain wavelengths of light by vegetation using spectral vegetation indices in Ogun state, South-West of Nigeria. Satellite images were obtained and ground hyperspectral data acquired with a ground-based integration system called Analytical Spectral Device (ASD) Handheld2 Spectrometer. Spectral indicators were calculated from both systems were analysed and compared. The information derived from the analyses had shown the potential to monitor the changes of affected vegetation.