Remote Sensing in Developing Country-Nigeria : An Exploration

The paper examines remote sensing education, and research in Nigeria. Among the questions addressed in the paper are: (i) what is the situation of remote sensing education and research in Nigeria? (ii) what are the broad areas of research and topics that are addressed? (iii) what type of remote sensing and GIS software are used? (iv) what are the sources of satellite images used? (v) what are the institutional affiliation and departments of the researchers? (vi) what are the research coverage areas? and (vii) what are the major findings from the remote sensing images? The data used in the study is from extensive published article search from 2009 to 2013. Descriptive statistics is used to analyze the data. Descriptive statistics used include frequencies and percentages. Policy implications of the findings are discussed in the paper.


Introduction
Remote sensing is the collection of information relating to objects without being in physical contact with them.It is the process of acquiring data/information about objects/substances not in direct contact with the sensor, by gathering its inputs using electromagnetic radiation or acoustical waves that emanate from the targets of interest (Shaw & Burke, 2003;Teewu et al., 2005;Ali, 2010).The origins of remote sensing date back to a photography taken from a balloon in 1858, and by World War I the aeroplane had become the main platform from which aerial photography was collected (Areola, 1986;Teewu et al., 2005).Areola (1986) notes that the first aerial photographs taken from an aeroplane were those of Centocelli, Italy, in 1909 and that the first World War which began a few years later gave a great impetus to the development of aerial photographic interpretation, particularly for military purposes.Indeed aerial photographic reconnaissance of war fronts and enemy territories soon came to be regarded as being of utmost importance in the planning of both military offensives and counteroffensives; in assessing the military capabilities of the enemy; in safeguarding vital supply routes; and in making models of the terrain in order to plan troop movements and manoeuvres.In the preparation for and during the Second World War, the military intelligence establishments in Europe, Russia and America perfected their photographic interpretation techniques and developed better aerial photographic cameras and films (Areola, 1986).According to Areola, up to the end of the Second World War, aerial photographic interpretation was mainly developed for military intelligence, and most of the aerial photographs available then were classified documents.Nevertheless, significant advances had been made in the scientific and practical uses of aerial photography (Areola, 1986).During the inter-war period, film chemicals were developed that allowed colour and infra-red photograph: the latter was of particular interest to the military, as it highlighted camouflaged features (Teewu et al., 2005).Since the 1950s, and until in recent time, black and white aerial photography has been the basis of most Earth surface mapping: accounting for 99% of all topographic mapping (Petrie, 2000;Teewu et al., 2005).As observed in the literature, aerial photographs are no longer the only available type of imagery of the earth's surface; satellite and radar imagery are now very common.The techniques by which these other types of imagery are produced now constitute, together with aerial photography, the wider field of science known as remote sensing.Landsat Earth-observation satellites, operative since 1972, produce digital images in the visible and infra-red parts of the spectrum: each covers thousands of kilometers square, with sufficient detail to map many geo-ecological features (Teewu et al., 2005).Digital images have many advantages over photographs: digital data can be easily stored and processed by computers; perfect copies of an image can be made in a second.Teewu et al. (2005) notes that over 1999-2000 a new generation of satellites, utilizing 'spy-satellite' technology, began to provide commercially-available multi-spectral digital images that could rival the detail obtained by aerial photography.Other recent developments, such as millimeter-precision Global Positioning System (GPS) receivers, improved digital data compression software and internet transfers of remotely sensed data, have facilitated the use of remotely sensed data (Teewu et al., 2005).
Observation in the literature shows that remote sensing has some fundamental advantages at gathering information that make it a good tool in environmental monitoring and management.These have been listed by Barret and Curtis (1976) to include: a capability for recording more permanently detected patterns; play-back facility at different speeds; opportunity for informative (objective) analysis of observations to minimize personal peculiarities of observers; means of enhancing images to reveal or highlight selected phenomena; the synoptic view advantage offered by raise platform; ability to record data on otherwise inaccessible areas; ability to produce accurate data on large areas at desired time intervals and at relatively lower cost compared to the cost that would be incurred through ground survey methods; and, ability to record images in multispectral fashion at different stages, at different scale and spatial resolutions.To the developed world remote sensing is a cost saving method of acquiring raw data to update existing information, while for the developing countries especially those in Africa, it has provided an opportunity to obtain the first generations of information on some of their earth resources (Abiodun, 2000).
Observation from the literature shows that the greatest problems that have perhaps militated against the wholesome acceptance and application of remote sensing technology by most developing countries especially in Africa include lack of understanding of the role of space science and technology in the development process; shortage of trained manpower; financially related problems of remote sensing data; inadequate hardware and software facilities for image processing (Abiodun, 2000;Fagbami, 1993), and most importantly lack of contributory input to satellite launching and image acquisition processes.Table 1 shows the satellites in Africa.None of these satellites was launched by an African rocket or on an African soil.No African country has launch capability as of today.This paper examines remote sensing education and research in Nigeria.

Research Questions, Source of Data and Method of Data Analysis
The questions addressed in the paper are: 1) What is the situation of remote sensing education and research in Nigeria?
2) What are the broad areas of research and topics that are addressed?
3) What type of remote sensing and GIS software are used?4) What are the sources of satellite images used? 5) What are the institutional affiliation and departments of the researchers?6) What are the research coverage areas?and 7) What are the major findings from the remote sensing images?
The data used in the study is from extensive recent published article search (2009)(2010)(2011)(2012)(2013).The total number of articles used in the study is seventy-seven (77).Descriptive statistics is used to analyze the data.Descriptive statistics used include frequencies and percentages.

Remote Sensing Education and Research in Nigeria -An Overview
Until recently, aerial photo-interpretation is what is available and taught in schools in Nigeria.Areola (1986) writing about the advance of aerial photograph in less developed countries notes that after the Second World War, the advanced countries of Europe and America turned to the countries of the tropics for the much needed industrial raw materials to rebuild their damaged economies.In addition there were fears about possible world food shortages.In order to avert such food shortages plans were drawn up for agrarian and land use reforms in the overseas colonies of the European powers.It was in this spirit, for instance, that the World Land Use Survey was established in 1949 by the International Geographical Union through the influence of Sir Dudley Stamp.Although this project collapsed after some time, three countries, Cyprus, Iran and Sudan, were in fact, successfully surveyed.According to Areola, for many of these poor countries there were no maps at all so that, naturally, the survey groups had to turn to the use of aerial photographs.Also it soon became apparent to the colonial powers that maps were essential for development projects in the colonies.This meant that a programme of topographic mapping had to be embarked upon prior to, or simultaneously with, the development projects.The literature reveals that the failure of agricultural development projects in British East and West Africa during this period can in fact be linked at least in part, to the failure to survey and map the land initially (Areola, 1986).Most colonial powers after the war established topographic mapping, soil survey and land resource survey units in the colonies.In Britain, for instance, the Directorate of Overseas Surveys was created in 1946 to provide geodetic control and to map the colonial empire (Warren, 1969).According to Warren, by 1969 the Directorate had published maps, mostly to the scale of 1:50,000, covering more than 4.5 million square kilometers, over thirty different commonwealth countries throughout the world.According to Areola, the aerial photography was often obtained through special contacts with British firms specializing in aerial surveys, including Hunting Surveys and Aero Films Limited.The Land Resource, Division of the Directorate has been particularly active in Africa and other parts of the tropics.It has carried out land system mapping and land resource evaluation using aerial photographs in parts of Nigeria, the Gambia, Kenya, Malawi, Lesotho, Ethiopia, Zambia, Botswana, Tanzania, and the Seychelles.According to Areola (1986), in the French territories in Africa, many agricultural and soil survey organizations were very active under the general direction of the French Office de la Recherche Scientifique et Technique Outremer (ORSTOM).In the Congo, the Belgian Institut National pour L'Etude Agrnomique au Congo (INEAC) was the main survey organization.The United Nations Food and Agricultural Organization, sometimes in association with the United Nations Educational and Scientific Organization, have also applied aerial photographic interpretation techniques in soil, land use and land evaluation surveys in different parts of Africa.
As observed in the literature there is gross underutilization of aerial photo-interpretation techniques in Africa (Areola, 1986).According to Areola, inspite of the fairly wide coverage of aerial photography in Africa, aerial photo-interpretation techniques are not fully integrated into the routine data gathering system in many countries.This according to him is perhaps, because aerial photo-interpretation is still generally regarded as a highly specialized technique meant for the use of only a small group of specialists in the field.Areola also notes that aerial photo-interpretation is not taught in most schools and colleges.Among other reasons mentioned by him as being responsible for the gross underutilization of aerial photo-interpretation techniques in Africa include the prevailing high cost of aerial photographs and that aerial photographs are not made readily available for general use by the survey departments -the restriction on the circulation of aerial photographs being ostensibly for security reasons (Areola, 1986).
In an attempt at building remote sensing capabilities in Nigeria, in 1993, the National Agency for Science and Engineering Infrastructure (NASENI) set up a committee to formulate a National Space Science and Technology Policy for the country.The policy recommended among other things the creation of centres of excellence for the development of space science and technology; and the enhancement of the capabilities of institutions offering space related courses of study in the country.In 1999, the National Space Research and Development Agency (NASRDA) was established to pursue the development and application of space science and technology for the socio-economic benefits of the nation.In 2001, the government approved the National Space Policy and Programmes to serve as, roadmaps for transforming Nigeria from the status of a consumer nation to an active participant in space technology and allied fields.The objective of the National Space Policy and Programmes was to make space research and development activities part of the overall strategies for sustainable national development.The main thrust of the National Space Policy and Programmes were: development of human resources and capacity building in various areas of space science and technology; to develop and build competence in space technologies of direct relevance to national development; to develop strategies and space applications; to undertake national resource management; defence, national security and law enforcement; study of the earth environment; communication and information; education and training; provide support for universities and other academic institutions in space related research and development projects; promote private sector participation in the space industry; promote international cooperation.In order to achieve these, six centres were created to act as the operational limbs of the National Space Research and Development Agency (NASRDA).These NASRDA centres are: a. Centre for Satellite Technology Development (CSTD): this centre has the primary focus on satellite technology development with indigenous critical mass of engineers and scientists in all rudiments of satellites technology -building, launching, telemetry, tracking and control of all kinds of satellites such as earth observation, communication, weather, scientific research, etc. b.National Centre for Remote Sensing (NCRS): this centre is charged with the sole responsibility of harmonizing research and development in space science and technology application for sustainable socio-economic development in the country.c.Centre for Space Science and Technology Education (CSSTE): this centre is affiliated to the United Nations African Regional Centre for Space Science.Its main function is to develop curriculum, skills and knowledge of university educators, research scientists and train other professionals and personnel in applications of satellite remote sensing, meteorology, communication and geographic information system to sustainable development.
d. Centre for Space Transport and Propulsion: this centre focuses on rapid advances in the science and technology of rocketry, which are the main transportation vehicles.e. Centre for Geodesy and Geodynamics (CGG): this centre was established to facilitate capacity for geodetic surveying and mapping, as well as monitoring of coastal deformation and subsidence due to excessive oil and gas exploitation, floods and global mean sea level rise and other related seismic and geodynamic phenomena including implementation of international agreements with respect to satellite laser ranging (SLR), very long baseline interferometry (VLBI) and cooperative international GPS network.f.
Centre for Basic Space Science (CBSS): the centre is mandated to provide a sound education, research and knowledge in basic space science, astronomy/astrophysics, rocketry and balloons, geomagnetism, etc as well as designing and fabricating appropriate systems and instrumentations and telescopes.
To date, five satellites have been launched by the Nigerian government into outer space, one of these satellite was a failure.The NigeriaSat-1 (first satellite), NigeriaSat-2 (third satellite) and NigeriaSat-X (fourth satellite) were for world-wide Disaster Monitoring Constellation (DMC).The objectives of the satellites include: to give early warning signals of environmental disaster; to help detect and control desertification in the northern part of Nigeria; to assist in demographic planning; to establish the relationship between malaria vectors and the environment that breeds malaria and to give early warning signals on future outbreaks of meningitis using remote sensing technology; to provide the technology needed to bring education to all parts of the country through distant learning; and to aid in conflict resolution and border disputes by mapping out state and international borders.NigComSat-1 is the Nigerian second satellite ordered and built in China in 2004, was Africa's first communication satellite.It failed in orbit after running out of power and was replaced by NigComSat-1R (fifth satellite).Table 2 shows the description of Nigeria satellite.

Research Findings and Discussion
Table 3 shows the year of publication of the articles, number of the authors and percentage.This table shows that 7.8% of the articles are published in 2009, 10.4% are published in 2010, 19.5% are published in 2011, 28.6% are published in 2012 and 33.7% are published in 2013.This shows an increase in the publication on remote sensing in Nigeria.Number of authors publishing on remote sensing shows similar pattern.The percentages of authors in 2009 is 4.2%, in 2010, it is 14.5%, in 2011 it is 21.7%, in 2012 and 2013 it is 26.5% and 33.1% respectively.This observation of increasing trend in the volume of remote sensing publications and researchers in Nigeria is an indication of healthy development and suggest a growing interest in remote sensing in Nigeria.This suggests a future bright prospect for remote sensing and GIS business in Nigeria.
In remote sensing, there are diverse research areas, topics and topic applications.All these diverse areas of research can be broadly divided into two which are method development and analysis/application.The articles used in the study are sorted into these two broad areas of research.It is observed that all the seventy-seven articles focus on analysis/application and none of the article focus on method development (Table 4).NigeriaSat-2 NigeriaSat-2 is the third satellite, with 300 kg mass was built as a high resolution earth satellite by SSTL for DMC system.It has 2.5-metre resolution panchromatic (very high resolution), 5-metre multispectral (high resolution, NIR red, green and red bands), and 32-metre multispectral (medium resolution, NIR red, green and red bands) antennas.
NigeriaSat-X NigeriaSat-X is the fourth satellite.NigeriaSat-X is based on the SSTL-100 and is developed by SSTL in association with a team of Nigerian trainee engineers at SSTL's facilities in England under their supervision.The key features of the NigeriaSat-X include: 22 m next generation imager with improved resolutions and optics over the same swath areas as DMC+, Swath of 600 km @ 8 bit, High rate X-band downlink set to 20 Mbit/s, Low rate S-band at 8 Mbit/s, 2 x 2 GByte data recorders.The NigeriaSat-X sensor provide 22 m multi-spectral (R, G, NIR) imagery.The data volume is estimated to be a handful of images per day.The onboard storage is different between NigeriaSat-X and NigeriaSat-2; NigeriaSat-X uses SSDRs (Solid State Data Recorders), while NigeriaSat-2 uses HSDRs (High Speed Data Recorders).
NigComSat Observation from the literature show that there has been low scientific research output contribution from African countries.In East African countries, in the field of GIS and remote sensing, the greatest knowledge, skill and productivity gap identified is developer that is, remote sensing and GIS method development (Simons, 2013).It is also observed from a concept note of a recent workshop on "expanding and sustaining excellence in doctoral programmes in Sub-Saharan Africa: what needs to be done?"organized by South Africa's National Research Foundation and the Carnegie Corporation of New York held in South Africa that while rapidly expanding economies elsewhere had more than doubled their rates of scientific publication in the past decades, Sub-Saharan Africa contributed only 0.7% to World scientific output and this percentage was decreasing and only three countries in Africa -South Africa, Egypt and Nigeria -produced three quarters of Africa's output (McGregor, 2013).
When these articles are further sorted into broad areas of topic (Table 5) and topic applications (Table 6), three broad areas of topics are identified which are land use/land cover, socioeconomic and disaster management, while nine topic applications are identified which are change detection/use and cover patterns, damage assessment/vulnerability, population, urban and regional planning, agriculture, health, geology, climatology and energy.Majority of the researches are on land use/land cover (87.0%) followed by disaster management (7.8%) and socioeconomic (5.2%).Also most of the topic applications are on change detection/use and cover patterns (42.9%) followed by urban and regional planning (18.2%), geology (11.9%), damage assessment/vulnerability (9.0%), agriculture (7.8%), climatology (6.5%), population (1.3%), health (1.3%), and energy (1.3%) in that order.Table 7 shows the remote sensing and GIS software used by the researchers.The table shows that ILWIS software was the most used software (35.4%),ArcGIS 9 software (19.5%),Arcview 3 software (18.3%),Idrisi software (13.4%),Erdas Imagine Software (8.5%), ArcGIS 10 software (2.4%), and ENVI software (2.4%).In some of the articles more than one type of software were used (that is why the total frequency number of software used is 82) while in 19.5% of the articles, the software used was not mentioned.11 show that most of the researchers are from Federal universities (45.0%), followed by those from State universities (26.3%), and then private universities (9.8%).The table further shows that 25.6% of the total universities in Nigeria featured out of which 14.0% are Federal universities, 7.8% are State universities and 3.9% are private universities.
Table 12 shows the research coverage area, publication numbers and percentage as well as some of the major findings from the remote sensing images.Appendix 1 shows the list of the articles by research coverage area, year of publication and the name of the author(s).Table 12 shows that the highest percentages of researches are on South West area of Nigeria (24.7%) followed by researches on North Central area of Nigeria (22.1%),North West area (19.5%),South South (Niger Delta) area of Nigeria (16.9%),North East area of Nigeria (7.8%) and South East area of Nigeria (6.5%).South west area of Nigeria comprises of the following states Lagos, Ogun, Oyo, Osun, Ondo, and Ekiti states.In the South West area of Nigeria, findings from the images revealed a steady decline in forest area and the expansion in farmlands, fallow ground and built up/residential areas.North Central area of Nigeria comprises of the following states Kwara, Kogi, Plateau, Nassarawa, Benue, Niger and Federal Capital Territory (FCT).In the North Central area of Nigeria, findings from the images revealed that while the built-up area increased, vegetation cover decreased at an alarming rate.Urbanization process is observed to be responsible for land use/land cover change.North West area of Nigeria comprises of the following states Sokoto, Zamfara, Kebbi, Kaduna, Katsina, Kano and Jigawa states.In the North West area of Nigeria, findings from the images revealed significant rapid growth in city/residential land use while the vegetation is diminished.Open spaces constituted the most extensive type of land use/land cover.Cultivated land is also observed to be decreasing.South South area of Nigeria comprises of the following states Edo, Delta, Rivers, Bayelsa, Cross River and Akwa-Ibom states.In the South South and the Niger Delta areas in general, findings from the images show high rate of land use/land cover change.Oil spill area is increasing, area covered by mangrove forest is declining, and urban land use is increasing in area extent.Determinants of forest dynamics are observed to include the variations in state forest management policies and the influence of the oil and gas industry on the economies of the states.North East area of Nigeria comprises of the following states Taraba, Adamawa, Borno, Yobe, Bauchi and Gombe States.In the North East area of Nigeria, findings from the images show increase in built up areas/land areas put under man's use and decrease in woodlands the only natural vegetation cover in the area.Factors observed to be responsible for land use/land cover change include extensive agriculture, animal grazing, intensive agriculture, tree crop farming, irrigation agriculture, wood cutting, bush burning and road construction.South East area of Nigeria comprises of the following states Anambra, Enugu, Ebonyi, Imo and Abia states.In the South East area, findings from the images show that high forest and agricultural land has been decreasing, built-up area has been increasing.

Table 1 .
Satellites in Africa

Table 2 .
Description of Nigeria satellite

Table 3 .
Year of the publication of the articles used in the study, number of authors and percentage -1 A Geostationary Satellite, NigComSat-1, built in China in 2004, was Nigeria' second satellite and Africa's first communication satellite.It was launched on 14 th May 2007, aboard a Chinese Long March 3B carrier rocket, from the Xichang Satellite Launch Centre in China.It was over 5 Tons Wet Mass.It was based on the Chinese DFH-4 satellite bus, and carries a variety of transponders: 4 C-band; 14 Ku-band; 8 Ka-band; and 2 L-band.It was designed to provide coverage to many parts of Africa and Middle East, and the Ka-band transponders would also cover Italy.It has a lifespan of 15 years.NigComSat-1 failed in orbit after running out of power due to an anomaly in its solar array.On 10 th November 2008 (0900 GMT), the satellite was reportedly switched off for analysis and to avoid a possible collision with other satellites.The satellite was a total loss.

Table 5 .
Broad topics

Table 7 .
Remote sensing and GIS software used by the authors Table8shows that the sources of images used by the researchers are from diverse sources prominent among which are Global Land Cover Facility (GLCF) of the University of Maryland, Maryland, USA (18.5%);Google Earth (18.5%);National Space Research and Development (NASRDA) Abuja, Nigeria (16.7%); and National Centre for Remote Sensing (NCRS) Jos, Nigeria (13.0%).

Table 8 .
Sources of satellite images used by the authors Tables 9, 10 and 11 show the department of the researchers, institutional affiliation of the researchers and the type of the university institution of the researchers.Table9show that majority of the researchers are from Department of Geography/ Geography and Environmental Management/ Geography and Planning/Geographic Information System (47.0%), followed by those from Research Institutes/Agencies/Centres (12.1%),Department of Urban and Regional Planning (9.0%),Department of Geology and Mineral Sciences/Applied Geology/Earth Science/Geoscience (9.0%),Department of Environmental Management/Environmental Management & Toxicology (4.8%),Department of Surveying and Geoinformatics (4.8%), and Department of Physics and Solar Energy/ Pure and Applied Physics (2.4%).

Table 10
show that majority of the researchers are from University institution (81.3%), followed by those from Research institutes/Agencies/Centres (12.1%), and Polytechnic institution (1.8%).

Table 10 .
Types of Institutional affiliation of the authors

Table 11 .
Type of university institution affiliation of researchers The source of this figure is from National University Commission of Nigeria web site.

Table 12 .
Publications by research coverage area and some of the major findings from the remote sensing images Findings from the images show high rate of land use/land cover change.Oil spill area is increasing, area covered by mangrove forest is declining, and urban land use is increasing in area extent.Findings from the images revealed a steady decline in forest area and land use intensification with the expansion in farmlands, fallow ground and built up/residential areas.Findings from the images show that high forest and agricultural land has been decreasing, built-up area has been increasing.Some of the major findings from the images revealed that while the built-up area increased, vegetation cover decreased at an alarming rate.Some of the major findings from the images revealed significant rapid growth in city/residential land use while the vegetation is diminished.Open spaces constituted the most extensive type of land use/land cover.Cultivated land is also observed to be decreasing.Some of the major findings from the images show increase in built up areas/land areas put under man's use and decrease in woodlands the only natural vegetation cover in the area.