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International Journal of Scientific Innovations Volume 8, Number 1, 2020. ISSN: 2276-6154

Copyright© Pan-African Book Company 2020 Online Publication: www.irdionline.org in the Pan-African Journal Series

TOPOGRAPHIC INFORMATION SYSTEM: A TOOL FOR ENVIRONMENTAL MANAGEMENT

1 Surv. Olatunde Faith Ozofu, 2 Surv. Olatunde Michael Banji, 3 Izah, Ngozi Linda and 4 Idris, H.

1 – 4 Department of Surveying and Geoinformatics Auchi Polytechnic, Auchi, Edo State, Nigeria

ABSTRACT There is a great increase in the demand for topographic information for various needs and applications by numerous users from a global point of view. There is no meaningful development that could be embarked upon by individual, government and other agencies without information of the topography to be developed. This paper focussed on the development of topographic information system as a tool for environmental management. The study area is part of Auchi Polytechnic (campus 1) Auchi, Edo State. Topographic Information System (TIS) is an approach in the management of geo-data by creating a database system that contains related data about geographical details organised and arranged in a logical manner that allows for easy updating, storage, retrieval, analyses and display. The project planning exercise was embarked upon by considering the possibility of achieving the aim through adherence to well defined objectives. Office and field reconnaissance exercises were conducted to ensure availability of adequate control points, existing map of the area and itch free field exercise. Ground surveying method of data acquisition using Total Station and other accessories were adopted. The non-spatial data were obtained through social survey and interactions with the people. The data were divided into locational and attribute data. The Total Station was employed in capturing X, Y, Z coordinates of points and features within the project site. It was used in angular mode for the perimeter traverse and coordinate mode for detailing and spot heightening. The graphic drafting was done using AutoCAD Land Development. Suffer 8 software was used for the contouring and generating the Digital Terrain Models. Data processing, structuring, management, manipulation and various spatial functions were carried out using ArcGIS 10.1 software. It was concluded that topographic information system is essential to any government, individuals, environmentalists and engineers in executing and developing infrastructural placement for physical planning and up to date decision making. The system allows easy up dating and quick retrieval of topographic information for better planning and environmental management. Keywords: Topographic Information System (TIS), Topography, Data Processing, Database Management and Environmental Management.

INTRODUCTION Land Surveying is the bedrock of any development. It is the first point of reference to any meaningful land development projects. Land Surveying products are of immense importance and vital tools in terms of infrastructural placement, management of natural events and human actions such as erosion, flooding, earthquakes and exploitation of minerals. Land Surveying is the measurement and mapping of our surrounding environment using mathematics, specialised technology and equipment. Surveyors measure just anything on the land, in the sky or on the ocean bed. Correspondence Author: Surv. Olatunde Faith Ozofu:

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Topographic Information System: A Tool for Environmental Management They are the first people on any construction site, measuring and mapping the land. They work closely with their peers in the fields of engineering, architecture, geology and planning. Their roles cannot be under estimated. Surveying is the process of analysing and recording the characteristics of a land area span to help design a plan or map for construction (www.civilsimplified.com). Ghilani and Wolf (2008), considered Surveying being interchangeably called Geomatics, as a discipline which encompasses all methods for measuring and collecting information about the physical earth and our environment, processing that information and disseminating a variety of resulting products to a wide range of clients. Surveying has been important since the beginning of civilization. The initial application of surveying was in the area of demarcating landed properties but its importance has steadily increased with the growing demand for a variety of maps and other spatially related types of information and the expanding need for establishing accurate line and grade to guide construction operations. There are specialised types of surveying ranging from Cadastral Surveying, Topographical Surveying, As-Built Surveying, Photogrammetry (Aerial Surveying), Control surveys, Hydrographic surveys, Alignment surveys, solar surveys and Satellite surveys. Topographical surveying which is a type of land surveying are surveys carried out to determine land structure along with variation in land heights. It deals with the acquisition of planimetric and height information of features on the earth surface of both man-made and natural features in three dimensions. It is a type of plane surveying and a third order survey where traversing and levelling exercises are employ to establish horizontal (planimetric) and vertical (height) information respectively. It is a survey where the X,Y,Z of positions are established. Topography is the study and description of the physical features of an area in terms of its hills, valleys, rivers etc or the representation of these features on maps. It describes the surface characteristics of relief features of such area as depicted by man-made and natural features. Digital technology was successfully introduced in the field of mapping in the late 1960’s as means of speeding up map production (Perera and Shanta 2002). Due to the recent development in technology and growth in the number of spatial data and its management, the concept of topographic database creation and management as well as Topographic Information Systems have evolved as a way of making Geo-information available to users. Topographic Information System is a geo-database management system that contains related data about geographical feature organised in logical manner that allow for easy updating, storage, retrieval, analyses and display. This system can be derived from the topographical data with the application of Geographic Information System (GIS). According to Burrough (1986), GIS is a powerful set of tools for collecting, storing, retrieving at will, transforming and displaying spatial data from the real world for a particular set of purposes. Most topographical maps available in Nigeria today are outdated and in analogue format. Presently, the country after over fifty years of independence, still lacks up to date topographic map of the country which is an essential ingredient for the creation of economic wealth, vulnerability mapping, social stability, strategic planning and environmental management and protection. Igbokwe and Ono (2005), observed that the fundamental and thematic datasets in the country are still in analogue form and few that are current are grossly outdated. This made them to conclude that implementation of National Geo-spatial Data Infrastructure (NGDI) project should inevitably run concurrently with coordinated revision of the existing datasets and their conversion to digital format. Regrettably, the exercise is not progressing at the expected speed and generally the impact is not been felt. Topographic surveys are one of the most important categories of surveying in which the data collected are drawn onto three dimensional contour maps. Topographic maps are important because they portray the surface of the earth in detail. It is therefore evident from the foregoing that no meaningful development can be embarked upon by relevant engineers, architects, environmentalists, individuals, government and other agencies without information about the topography of the location where such development is to take place.

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Aweh, Olatunde, & Olatunde (2013), observed that producing a functioning topographic GIS database is capable of addressing and proffering solutions/answers to specific questions and that it is a critical tool for making any informed decisions on key economic, environmental and social issues for sustainability. Environmental management is no doubt a sine qua non for a sustainable built environment. As a resource to any nation, the environment should be well planned, developed, conserved and managed (Adedokun and Adewara, 2017).It is of great necessity to measure and monitor our environment today as a result of the alarming increase of our population, appreciation in land values, dwindling of our natural resources and effects of human activities on our land, water and air which continually stress our environment and atmosphere leading to natural phenomenon like global warming and depletion of the ozone layer. It was also stated by Ghilani and Wolf (2008) that contemporary Surveyors can use modern ground, aerial and satellite technologies and computers for data processing to measure and monitor the Earth and its natural resources on literally a global basis. Never before has so much information been available for assessing current conditions, making sound planning decisions and formulating policy in a host of land use, resource development and environmental preservation applications. Karl, (1995) defined Topographic Information System in three sections. It was defined in the first section as one of the three categories of spatial information, in the second section, it was considered a new solution outlined for the mathematical surface modelling of a digital elevation model. In the third section, it was defined as additional data which serve to create a TIS from a DEM were discussed. Topographic Information System is a Geo-database management system that contains related data about geographical feature organised in logical manner that allows for easy updating, storage, retrieval, analyses and display. The need for up-to-date TIS of our environment cannot be over emphasized. It is most desirable in a country like ours where urban development/spatial data consumption is higher.

Study Area The study area is part ofcampus 1 Auchi Polytechnic, Auchi, Edo state, Nigeria (see fig 1). It is located along Benin-Abuja express road in Etsako West Local Government Area. It lies between Latitude 070 12’ 20” and 070 12’ 29” North of the Equator and Longitude 060 20’ 10” and 060 20’ 15” East of Greenwich Meridian. The polytechnic is the oldest tertiary institution in the locality. It was formally a technical institution at inception and was later up graded to a polytechnic. It runs both regular and some part time programmes in about seven schools in the polytechnic. The schools are school of engineering, environmental studies, applied sciences, business studies and administration, art and industrial design, general studies and ICT and communication technology. The school has been experiencing high degree of expansion and development as a result of the increasing number of students being admitted yearly and for the management to cope with the high demand for conducive environment for learning and human activities within the campus, other campuses such as campus 1 and campus 2 were built to avoid overcrowding and congestion of campus1. Auchi Polytechnic Campus 1 is the main campus where all developments and innovations have evolved. In order to provide an aesthetic environment for human habitation and learning there is need for proper planning and decision making of the environment through the production of a topographic information system of the area.

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NIGERIA MAP EDO STATE MAP

AUCHI POLYTECHNIC IMAGE ETSAKO WEST LGA

Fig 1: Map of Study Area

MATERIALS AND METHOD Primary and secondary data were acquired for the execution of this study. Reconnaissance (office and field) was adequately executed and necessary data and information were obtained. Existing map of the study area was obtained and studied to identify existing control points to be used for traversing and spot heightening. These controls were verified to ascertain their reliability. Total station was used in angular mode for the perimeter traverse and in coordinate mode for detailing and heightening both perimeter and grid heightening. Coordinates of the traverse points were obtained after the forward and back computation was done while the heights (perimeter and grid) and detailing were recorded with appropriate identity. Sokkia 210 Total Station and its accessories were used for the perimeter traverse in angular mode while detailing and spot heightening was executed in coordinate mode. Hp Intel core i7 laptop, 160GB Hard Disk, CD-ROM and Laser Hp 4100N A4 printer were the systems selected for this study. The software includes Microsoft word for report writing, Microsoft excel for editing, Notepad for running of script, AutoCAD 2010 for plotting the boundary and details, Suffer 8 for contour generation and ArcGIS 10.1 for spatial data management and analysis. This study employed vector approach of data acquisition where by the Northings and Eastings of the boundary points were determined using the Total Station and also the same equipment was used to locate details and obtain the reduced level (height) of the boundary points and grid corners.

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The Total Station was tested for horizontal collimation and vertical index errors and was ascertain to be in adjustment. The principle of working from whole to part and connecting a new survey to existing controls was adhered to. The existing controls (AUM 4, DLS1 and DLS2) were verified to be in-situ before being used for connection. A closed loop traverse was run with angular mis-closure of 12”and linear accuracy of 1/36,000. The attribute data were acquired through social survey of structured questionnaire and interviewing to get necessary information of geographic features of the study and some acquired through field observation. These attribute data acquired include building name, type and use. RESULTS AND DISCUSSION The spatial analytical capabilities of GIS differentiates it from other information system such as spatial search, neighbourhood and connectivity operations. The database was tested to ensure that the relationship between the data about the objects and their attributes are capable of being retrieved. This was done by designing a sample query and running them to see if the outcome result is applicable it was hence, the database was confirmed fit for analyses. Fig 2: Topographic Map of the Study Area

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Topographic Information System: A Tool for Environmental Management Topographical Operations and Analyses Topographical operations were carried out on the Digital Elevation Model (DEM) of ground heights generated for the study area using Surfer 9 software and ArcGIS 10.1 for topographical analysis. The essence is to determine the surface characteristics of the study area from the spot height dataset. The following topographical analyses were carried out while various overlays generated other new output. Overlay Operation The contour map was overlaid on the detailed map of the study area to produce the topographic map of the area (fig 2). This map is a vital tool in planning and control of erosion in the study area. Also, the detailed map of the area under investigation can be used to ascertain area that are available for further developments and those that have been used up. It shows the relationships that exist between the various spatial entities. This result can be used to determine area that need access road to be built or other facilities. The major analyses performed in this project were overlay operations, query generation, topographic operations, and buffering. Hill Shade Map of the study area (Fig 3) is essential in presenting a portrayal of relief difference and terrain morphology in hilly mountainous area. It can also be used to determine best part of a place to be reserved for drying of crops in the case of farmland. For the study area, it will be useful in determining best places for students/staff relaxations and car parks.

Fig 3: Hill Shade Map of the Study Area

Slope Map of the study area (Fig 4) will be useful in determining the gradient of the place as this will help in drainage construction and subsequently in soil erosion control in the study area.

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Fig 4: Slope Map of the Study Area

Triangulated Irregular Network (TIN) Map of the study area (Fig 5), provides the elevation model. It is the basis for other analysis such as slope, aspect etc. it is useful for spatial planning of the area, resource management, engineering works, volume of earthwork calculation etc

Fig 5: TIN Map of the Study Area Buffering Query analysis was performed as shown below (Fig 7). Buffer is a function in GIS that help to generate zone of influence around a particular target feature with regard to distance and other features within the neighbourhood. It reveals the degree of impact a feature has on the other features in the same location. For this study the roads were buffered by a distance of 10m to know the structure(s) that will be affected in case there is a future need to expand the roads by such distance.

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Fig 7: Roads Buffered By 10m RESULT ANALYSES AND DISCUSSION The topographic map of the study area can be used in very important areas such as building construction (both for administration, classrooms and hostels for student) and for the provision of other infrastructures within the school such as drainage system, conveniences, playground etc. It will also help to determine the difference in elevation in the study area which can be used to implement land use and planning for sustainable development and environmental management.With this type of topographic database, spatial analyses for solving complex planning and environmental problems can be carried out. Examples are spatial overlay, buffering, proximity analysis, 3-D scene (modelling) and line of sight analysis/profiling. Applications of Products The various products generated in this study can be useful for planning purposes and decision making. The topographical map of Auchi Polytechnic, Campus 1 shows all the features as they exist on the ground and the available area for future development. The following are the areas of applications of the products generated: (i) Topographic map of the study area can be used in planning drainage, roads, development t

of water projects and can also be useful in determining the difference in terrain elevation. (ii) The Hill Shade Map is used to portray relief difference and terrain morphology in hilly and

mountainous areas. (iii) Slope map of the study area will help in determining a good drainage system (iv) Aspect map will help in ascertaining the direction of a slope surface and the duration of the

drainage (v) The TIN will help in planning and resources management, earth science, engineering works,

visualization of a 3 dimensional surface, volume calculation etc Other products generated from the queries, can be used for physical planning, decision making and proffering solutions to spatial problems of the polytechnic. The products are all useful for analysis of our physical and environmental management.

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International Journal of Scientific Innovations Volume 8, Number 1, 2020. ISSN: 2276-6154 CONCLUSION AND RECOMMENDATIONS From the study, it was discovered and confirmed that topographic information system is a necessary tool for managing related environmental issues and problems. With this type of system, it is possible to update, retrieve, analyse and manage the data in the system quickly. Many important spatial problems in the area can be tackled easily. It can supply data for producing flexible and interactive maps of the area. The inclusion of topographic dataset in the spatial data infrastructure of any place, provides a comprehensive information base with capacity for multi-disciplinary, multi-user applications to managers of defined objectives, planners and resource managers and the public at large for solving complex planning and management problems in a cost-effective manner. Adewara & Kolawole (2017) opined that up to date digital map produced from satellite images are very vital in developmental process, infrastructure maintenance, fault detection and rectification by any utility management scheme and also that TIS, should be adopted to support environmental management and use as a decision making tool. It is worthwhile, to adopt this system at every level of development in the society in order to provide a conducive, aesthetic and well planned environment devoid of environmental disasters such as flooding. REFERENCES Adedokun, A.M.& Adewara, M.B. (2017): Application of satellite data for a sustainable built environment.1st National Conference of School of Environmental Studies, Federal Polytechnic Offa, Kwara State. Adewara M.B.& Kolawole O.A. (2018): ‘Topographic Information System (TIS) A Tool for Effective Planning and Proper Environmental Management (A part of the Federal Polytechnic Ilaro, Nigeria)www.academia .edu/3485 retrieved September, 2018 Aweh, D.S, Olatunde, M.B.& Olatunde, F.O. (2013): ‘Topographical Map Revision Using GIS and Remote Sensing Technology: A Vehicle for Sustainable Development (A Study of Benin City and Environs).’ 7th Environmental Conference, Auchi Polytechnic, Auchi. Burrough, P.A. (1986): Principles of Geographic Information Systems for Land Resources

Assessment. Clarendon Press, Oxford University Press, New York

Ghilani, C.D. and Wolf, P.R.(2008): Elementary Surveying: An Introduction to Geomatics. Twelfth Edition. Pearson Prentice Hall.

Godfrey-Hoffman and Hodge: ‘The Science of Topographic Surveys’ 26 Broadway North Haven, CT 06473 PH:203,239.4217. www.godfreyhoffman.com

Igbokwe, J.I. and Ono, M.N. (2005): Nigeria’s National Geo-spatial Data Infrastructure: Problems and Prospects. Proceedings of the International Federation of Surveyors Working Week 2005 and GSDI-8, April, 16th – 21st, Cairo, Egypt.

http://www.fig.net/pub/cairo/papers/ts31/ts31 07 igbokwe ono.pdf Karl, Kraus Vienna (1995): ‘From Digital Elevation to Topographic Information System’ Photogrammetry Week ‘95’ Wichmann Verlag Heidelberg D.Fritch & D. Hobbie (Eds) Perera, S. and Shanta, K.O. (2002): ‘A Topographic Database for Geoinformation Process in The Survey Department of Sri Lanka’ CEN-2020-003/J. Noah/newcentrejournal@yahoo.com/FRB/21/01/2020/IRDI/***476