GIS delineation of factors responsible for spatial distribution of poultry meat production in the Niger Delta: a case study of Delta State, Nigeria

T Omodele, I A Okere¹, C E Deinne² and M O Oladele-Bukola¹

Institute of Agricultural Research and Training, Land and Water Resources Management Programme, Obafemi Awolowo University,
P.M.B. 5029, Moor Plantation, Ibadan. Nigeria
modeltaiwo@yahoo.com
¹Institute of Agricultural Research and Training, Livestock Improvement Programme, Obafemi Awolowo University, Moor Plantation, Ibadan. Nigeria
²Geography Department, University of Ibadan, Ibadan. Nigeria.

Abstract

This study aimed to examine the factors responsible for the production distribution of poultry farms in Delta State through the use of Geographic Information Sys­tem (GIS) technology. The poultry production system in Delta State was classified by applying geographic positioning of all poultry farms within the State with the use of Global Positioning system (GPS).

There existed a very low poultry production of 14.1% in Delta State when compared with the highest producing State in Nigeria. GIS analysis showed production of poultry meat type as: Broilers 7.9%, Breeders 9.9%, Layers 81.2% and Cockerels 1%. Applying terrain analysis of classified landscape zones of Lowland (<20m) and Upland (≥20m): Lowland farms of 68.3% produced at 73.3% while Upland farms of 31.7% produced at 26.7%. The Lowland high production was as a result of high human population in the flood susceptible Lowland areas. While there was no poultry farm located at the wide mining areas of Mangrove forest and natural waterbodies along the coastline, landuse/landcover assessment showed that 74.5% of poultry farms spatially distributed across agricultural and cropping areas produced 88.7% of poultry meat. Analyzing the road network densities in Delta State, 1.1% of farms in Low Road Density (LRD) areas produced at 1.2%, 36.7% of farms in Medium Road Density (MRD) areas produced at 7.3%, 47.8% of farms in High Road Density (HRD) areas produced at 66.5% and 14.4% of farms in Very High Road Density (VHRD) areas produced at 25%. Application of GIS delineated the major factors responsible for the poultry meat production distribution as natural factors (mangrove forest, forested freshwater swamp, floodplains and waterbodies), availability of market (human population) and market access (road transportation).

Key words: coastal erosion, human population, land subsidence, LGAs, market access, terrain

Introduction

The Food and Agriculture Organization of the United Nations defines food security as “a situation that exists when all people, at all times, have physical, social and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life” (FAO 2002). This definition implies that food insecurity reflects uncertain access to enough and appropriate foods (Barrett 2002). Food security is widely recognized to encompass three major concepts: availability, access, and utilization. Availability in the macro sense refers to the efforts by governments to ensure that sufficient quantities of food are available for the populace; access refers to the ability of households to obtain food in the market place or from other sources. The major constraints facing the agricultural sector and food price fluctuations are because of overexposure to world markets which reduce food access for the poorest Nigerians.

The disparity between the rate of food production and demand for food in the Niger Delta has led to increasing resort to food demand and high rates of increase in food prices. No doubt, food is life; hence, food has become an instrument of national power. It is within that imperatival need for food that several conferences and world Food summits on human nutrition have brought to the fore deliberations on issue of eradicating poverty and hunger. Nigeria’s agricultural policy noted that much still needs to be done if the crisis in the sector will not escalate more so, in a supposedly democratic dispensation which expectedly should promote the value of welfare. Production of food has not increased at the rate that can meet the increasing population in the Niger Delta region. While food production increases at the rate of 2.5%, food demand increases at a rate of more than 3.5% due to high rate of population growth of 2.83% (CBN, 2004). With the urbanization of the population, proportionally fewer numbers of people are involved in food production and without effective measures of control; the population will soon outgrow food production in the area. The growth in population and the increasing urbanization leads to the need to produce larger quantities of food being transported over longer distances.

The Niger Delta, the delta of the Niger River in Nigeria is a very densely populated region where larger areas of land were dedicated to agricultural activities. Its coastal region is under continuous human pressure and changing climate. The effects of climate change manifest in gradual sea level rise, which can be compounded by local land subsidence. Thus the region is particularly sensitive and susceptible to alteration in sea level. Land subsidence, which contributes to relative sea level rise, is particularly common in areas of continuous subterranean fluid extraction, such as the Niger Delta, characterized by prolific oil exploitation. This implies that the Niger Delta is susceptible to both global changes in climatic trajectory and local environmental challenges such as land subsidence, which results in relative sea level rise. Areas under threat arising from different scenarios of sea level have not been clearly delineated even though studies have postulated the extent of land coverage at risk of lost to sea level increases of particular dimensions (Awosika, et al, 1992). The brackish water in the delta and along the coast are an ideal environment for mangrove forests, which cover 653,669 hectares, are the largest in Africa and the fifth largest in the world (Giri et al. 2011). However, the mangrove forests have dwindled over the last two decades due to urbanization, dredging activities, and pollution from oil and gas industries (Adedeji, Ibeh, and Oyebanji 2011). Analysis based on a coarse digital terrain model showed that much of the population in the deltas is at risk through coastal erosion and land loss, primarily as a result of decreased sediment delivery by the rivers, and also through accentuated rates of sea-level rise (Ericson, et al, 2006). The Niger delta is considered to be under moderate vulnerability with indicative population potentially displaced by current sea level trends to 2050 (Ericson, et al, 2006; Nicholls, et al, 2007).

Economic development of any society is a complex process, which depends on several interacting forces. Perhaps one of the most important of these forces is the provision of adequate transport infrastructures. This is particularly true in the largely subsistence economy of most African countries where transport constitutes the key to development especially at the early stages of economic advance. The interaction between the level and pattern of transport resources and the standard of living of the population of any country is a critical factor affecting economic and social progress. Thus in most African countries today, there is widespread concern for transport planning in the desire to promote rapid economic development. This is reflected in the various National Development Plans of the different West African countries in which the transport sector consumes a significant proportion of the capital investment, ranging between 20 and 40 percent of all public sector investment (Ogundana, 1971; Atubi and Onokala, 2004). In Nigeria, road transportation is the most popular and developed. In consequence, both the Federal and State Governments have made enormous capital investment in the development of road transportation in the country especially in the urban centres. In the Niger Delta where a greater percentage of the local population resides in the rural areas the few urban centres enjoy comparatively better transport facilities than the larger rural environment. It has been observed that many rural settlements in the Niger Delta are not directly located on motorable roads and where they are located on roads, many do not particularly enjoy this advantage because the roads which serve them are liable to flooding during the rainy season. Economic and social activities are disrupted during these months in the rural areas and this has particular effect on the rural market system which may become redundant as a result of inaccessibility (Aloba, 1978).

Similarly, Stuckey (1973) wrote that transport facilitated economic advancement and transport improvement was indeed part of the economic advancement. A certain percentage of the economic activities arose directly because of new transport possibilities but for the most part, new transport facilities enabled the expansion of local activity and the integration of previously isolated market. In the latest review of urban Transport Strategy, World Bank (2001); Venter et al (2003) and Maunder et al (2004) recognized the need to address more systematically access issues, especially for those who are mobility impaired.

The importance of the poultry sub-sector is chiefly in the provision of meat and eggs as well as the provision of employment either directly or indirectly and the contribution to the revenue (Gross Domestic Product) of the country. The poultry sub-sector of the economy in Nigeria remains chiefly primitive. There is however no comprehensive data on the sub-sector; thus making proactive intervention and planning in the sub-sector difficult due to lack of accurate or current information. This is because government, at all levels, has neglected it for a long time. The poultry industry in Nigeria currently has about 10% of the population and is responsible for less than 15 to 18% employment opportunities, due to the fact that the industry is mainly subsistent (Afolami et al. 2011). The development of poultry system in Delta State is essentially characterized by small to large-scale production, capital and labour-intensive with high input and high output. Omodele and Okere (2014) reported that the highest production is in Ogun State in the South-west geopolitical zone of Nigeria. There are two distinct poultry production systems in Nigeria, as in most developing countries of Africa and Asia. Each of these two systems is associated with features of scale, stock, husbandry and productivity that therefore define the two distinct production systems. The two systems are conventionally referred to as the Commercial Poultry and the Rural Poultry, respectively. The Commercial Production System as the name implies is industrial in its prototype and therefore based on large, dense and uniform stocks of modern poultry hybrids. It is capital and labour intensive; as well as inputs and technology demanding. On the other hand, the Rural Poultry is by convention a subsistence system which comprises stocks of non-standard breeds or mixed strain, types and ages. It is generally of small scale, associated with household or grass root tenure and little or no veterinary inputs. The rural poultry sector is therefore in its original sense, a village-based, household or individual holding and occupation which has however been extended to non-village settings in peri-urban localities, mainly by the middle class dwellers. The common features to all these intermediate grades are in their subsistence scale generally, with minimal or no inputs and labour overheads. There is therefore need to investigate various factors responsible for variation in spatial distribution of poultry production in Nigeria especially in the coastal region of the Niger Delta where flooding and erosion are unavoidable as a result of gradual land subsidence been introduced through continuous human pressure and activities.

Geographic Information Sys­tem (GIS) forms the basis of geospatial delineation of factors responsible for the distribution of poultry meat production in the entire Niger Delta area as used in this paper. It involves employing geospatial analysis, which concerns what happens where, and makes use of geographic information that links features and phenomena on the earth’s surface to their location (Smith et al, 2007). The analysis being first of its kind in the Niger Delta lends more to the usefulness of GIS technology in the Niger Delta poultry industry. GIS technology in the country had promised an appreciable relief to the procedure of decision-making process where poultry farmers are shown their levels of production and areas where their services are required for efficient and sustainable production of poultry products.

Materials and Methods

Study area

Delta State is a State in Nigeria’s Niger Delta, comprising distinct Igbo subgroups of Enuani, Ukwani, Ndokwa and Ika, collectively referred to as Anioma, and the Delta people made up of the Urhobo, Itsekiri, Ijaw and Isoko ethnic groups. Delta is an oil and agricultural producing State of Nigeria, situated in the South-South geo-political zone with a population of 4,112,445 (males: 2,069,309; females: 2,043,136). The capital city is Asaba, located at the northern end of the State, with an estimated area of 762 square kilometres, while Ogwashi-Uku in Aniocha South LGA has the biggest land space for any industry; Warri is the economic nerve center of the State and also one of the most populated areas located in the southern end of the State. The State has a total land area of 17,239.24 square kilometres.

Figure 1. Study area: Local Government Areas of Delta State.

Survey of Poultry Farms

An intensive survey was carried out across all the 25 Local Government Areas (LGAs) in 2010 for determining the locations of poultry farms and creation of spatial dataset of all farms contributing to the development of the poultry sector in Delta State. This required the use of Global Positioning System (GPS) in order to assess the impacts of poultry farms in poultry production along various geographic trends (Figure 2). This farm survey determines the production estimates for the localities in the study area. The spatial data collected was accompanied by the administration of a set of questionnaire which was conducted through an interview session for obtaining information on the poultry meat production characteristics of the sampled farms.

Figure 2. Spatial distribution of poultry farms in Delta State LGAs.

Geographic delineation of poultry farms production distribution

The logically structured spatial and attribute data of the surveyed poultry farms were integrated and the obtained data of the poultry farms were logically queried and analyzed. Using ArcGIS 10.1® capabilities, queries generated were for the retrieval of information and provision of answers to likely questions that would be required. The geographical delineation of positions of the poultry farms was determined and the major queries performed were to evaluate the percentages of poultry farms that are major contributors within various geographical formations and to critically analyze the factors responsible for their production distribution in the study area.

Results and Discussion

General analysis of poultry meat production

By analyzing Table 1, the percentage production of poultry meat types in Delta State (Figure 3) shows that Layer is the most preferred poultry meat type in Delta State which is due to quick economic returns from production of meat and eggs. The analysis showed poultry meat production as: Layers (81.2%), Breeders (9.9%), Broilers (7.9%) and Cockerels (1%). Omodele and Okere (2014) reported that production of Layers is the highest in Nigeria. Further analysis showed that Delta State produced 14.1% of poultry meat as compared with the highest producer in Nigeria. Ogun State was discovered as the highest producer according to Omodele and Okere (2014). Figure 4 implies that production of poultry meat across various types is very low in Delta State.

Figure 3. Percentage production of poultry meat in Delta State.	Figure 4. Percentage poultry meat production disparity in Delta and Ogun States.

Poultry meat production and its distribution

As expressed in Figure 4, it was reconfirmed in Figure 5 that there exists a very low production of poultry meat in Delta State. The lowest production is more from the LGAs along the coastline. The production distribution showed that major production was from Ndokwa West, Ughelli North and Ika South Local Government Areas. Figure 6 emphasized that Ughelli North had the highest number or proportion of poultry farms in Delta State but it never had the highest production. This is a clear indication that the high number or proportion of poultry farms in an area does not guarantee a high production in such a locality as reported by Omodele et al (2014).

Figure 5. Distribution of poultry meat production in Delta State.	Figure 6. Percentage of farms and their meat production in Delta State.

Terrain delineation of production distribution

The terrain or topography of Delta State was digitally modelled using the Digital Elevation Model (DEM) of the area. For the purpose of this assessment, the landscape was divided into Lowland (<20m) and Upland (≥20m) zones as shown in Figure 7. The major areas of the State are in the Lowland regions with an area of 12615.2 SqKm (74.41%) while the Upland regions have an area of 4336.9 SqKm (25.6%). This made the area susceptible to flooding which adversely affects agricultural activities in the area. If sea level rises, inundation could occur along more 70% of the Nigerian coastline, placing land at risk many kilometers inland (Awosika et al., 1992). Table 2 showed that 68.3% of Delta State poultry farms in the Lowland areas produced 73.3% of poultry birds in the State while 31.7% of Delta State farms located in the Upland zones produced 26.7% of poultry birds. This is summarized in Figure 8. In line with the graphical display of Figure 5 in which highest production was located in the Local Government Areas in the Lowland areas. It is clear that there are more poultry production activities in the lowland areas than the Upland areas. It was earlier confirmed that the higher number or proportion of poultry farms in the Lowland areas resulted in the higher production of poultry meat in the area. The area coverage of Lowland zones might not be the factor responsible for this high proportion of farms and their high production, considering the studies of Omodele et. al. (2014) that high production is not guaranteed in such occurrences. Since it is presumed that human population tends to avoid slums and floodplains but the terrain had least influence on poultry production as it is confirmed that oil mining activities are carried out in the Lowland regions and the workforce (population) is expected to be high in the region.

Figure 7. Digital Elevation Model (DEM) classification of Delta State.	Figure 8. Percentages of disparity in farms proportion and production in the Lowland and Upland areas

Landuse/landcover delineation of production distribution

According to Figure 9, it was revealed that 74.5% of poultry farms are spatially distributed across areas used for agricultural purposes. This highest percentage of farms produced 88.7% of poultry meat in the study area. Also, about 16.1% of poultry farms produced 7.8% of poultry meat in the urban area while 3.3% of farms located very close to natural waterbodies had 2.8% of production. The farms located in the undisturbed forest, forested freshwater swamp and floodplain areas produced 0.3%, 0.3% and 0.1% respectively. There was no poultry farm located at the wide areas of mangrove forest and natural waterbodies around the coastline as these are the oil (petroleum) mining areas of the State. The high concentration of poultry farms in the areas for agriculture delineated that natural land formation and landuse patterns are parts of the determining factors of spatial distribution of farms in Delta State. This is summarized in Table 3 while Figure 10 displayed the profile of number of farms and their total production across various landuse classes. Poultry meat production is carried out conveniently on land as expressed by Figures 9 and 10.

Figure 9. Spatial distribution of poultry farms across landuse classes in Delta State.

Figure 10. Profile of poultry farms distribution and their production across landuse classes in Delta State.

Human population delineation of production distribution

Availability of market is the most important determining factor of poultry production. Omodele et. al. (2014) stated that population attracts increase in consumption of poultry products (meat and eggs) and it is known that high population connotes more of commercial activities as agricultural products have ready markets. As compared with the highest producer in Nigeria, poultry production in Delta State is relatively low. It is therefore apparent that production will be supplemented with products from neighbouring States. Geographical representation of Table 4 gives the distribution overview of population across Delta State. The population distribution across the LGAs predetermines the influence of population on production. Figure 11 showed a high human population in the Lowland areas of the study area. This confirmed the results of terrain delineation in which there was higher proportion of poultry farms which resulted in a higher production distribution in the Lowland areas. As expressed by Figure 9 that the LGAs along the coastline (petroleum mining areas) have landuse coverage of undisturbed forest, forested freshwater swamp, floodplains and natural waterbodies, it was also observed that these areas are in the low population class according to Figure 11 except in Burutu LGA where population was higher. The natural land formation and human activities like mining operations in the LGAs along the coastline led to the low human population in the area which indirectly affected poultry production activities in the region. Therefore poultry production distribution is delineated by concentration of human population which is the readily available market for poultry products.

Figure 11. Human population distribution in Delta State.

Road access delineation of production distribution

Accessibility is a term often used in transport and land use planning and is generally understood to mean the connectivity of a place with other places. A certain percentage of the economic activities arise directly because of transport possibilities which enables the expansion of local activity and the integration of previously isolated market. Geographical representation of various road types in Delta State (Table 5) is displayed in Figure 12. It was observed that areas with road network are the areas where agricultural activities are established and these are the areas where poultry farms were sited. Generally, poultry farmers are attracted into more production with the availability of access to market. Similarly, poor roads in the Local Government Areas have to be attended to so as to increase inter-community development and flow of agricultural produce especially poultry products from rural to urban centres. Analyzing all road network densities in Delta State (Figure 13), 1.1% of farms in Low Road Density (LRD) areas produced at 1.2%, 36.7% of farms in Medium Road Density (MRD) areas produced at 7.3%, 47.8% of farms in High Road Density (HRD) areas produced at 66.5% and 14.4% of farms in Very High Road Density (VHRD) areas produced at 25%. This is summarized in Table 5 and displayed in Figure 14. Using GIS techniques, it was uncovered that Local Government Areas with Medium Road Density (MRD), High Road Density (HRD) and Very High Road Density (VHRD) are areas with appreciable poultry meat production which was as a result of agricultural land availability. LGAs of Very Low Road Density (VLRD) and Low Road Density (LRD) are the areas of mangrove and freshwater swamp, which is fringed in the north by lowland rain forest zone. The mangroves and mud flats, some cultivated and fallow land, and freshwater swamps had been delineated and considered susceptible to future inundation and erosion/flooding therefore making the region unsuitable for agricultural practices especially poultry production. Generally, the swampy region has emerged as one of the most ecologically sensitive region in Nigeria, its sensitivity being greatly influenced by salinity and hydrological changes (SPDC, 1999; Raufu, 2000, in Fabiyi, 2008). However, no society can exist above the subsistence level without a measure of improvement in its transport system. According to Aloba (1985) and Atubi and Onokala (2003), areas with under-developed transport infrastructures are more disadvantaged than areas with an improved transport system.

Figure 12. Road (market access) network in Delta State.	Figure 13. Road (market access) densities in Delta State.

Figure 14. Percentage of poultry farms and their production across various road density classes.

Conclusion

• Various natural and man-made land formations dictated the spread pattern of poultry farms in the study area, in which poultry meat production is carried out conveniently on land especially in the agricultural prone areas.
  
  
• Production of meat types showed that Layer is the most preferred poultry meat type in Delta State which is due to quick economic returns from production of its meat and eggs.
  
  
• It was delineated that there are more poultry production activities in the Lowland areas than the Upland areas as a result of high human population on Lowlands. The high human population is due to oil mining activities in the Lowland areas of Delta State. Hence, population attracts increase in production and consumption of poultry products in the Niger Delta area. Poultry production in Delta State is relatively low and will have to be supplemented with products from neighbouring States.
  
  
• The high concentration of poultry farms in the agricultural areas delineated natural land formation and landuse patterns to be the determining factors of spatial distribution of farms in the area. There exists coastal erosion which pushes the population away from the coastline towards the Upland region while gradual land subsidence resulting from mining activities makes the area susceptible to flooding, adversely affecting agricultural activities and market accessibility.
  
  
• Market access plays an important role in the development of the poultry industry in Delta State.
  
  
• Geographic Information System (GIS) application revealed that natural and man-made land formations, human population, agricultural land availability and market access are the major factors responsible for the production distribution of poultry meat in the Niger Delta especially in Delta State.

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Received 23 August 2014; Accepted 18 October 2014; Published 3 November 2014

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