|Environment, Biodiversity and Agricultural Change in West Africa (UNU, 1997, 141 pages)|
|Pilot study of production pressure and environmental change in the forest-savanna zone of southern Ghana|
|10: Population growth and urban demand|
John S. Nabila
The growth of the population and the attendant increased pressure on the land and geographical redistribution of people, which appeared to be a fundamental factor in the environmental change in the southern sector of the forest-savanna transition zone, are examined in this paper using data from the PLEC 1993 field studies and from documentary sources. This factor can be discussed from the following viewpoints:
Each of these exerts its own demands on the agrobiophysical resources.
The population of the surveyed settlements had a substantial migrant component, and showed significant changes since 1960 (table 10.1). The phenomenal population growth in Amanase, Yensiso and Kokormu, in contrast to the general decline in Osonson, Whanabenya and Adenya, is indicative of population redistribution and adjustment in response to differential environmental conditions, including different degrees of environmental degradation as perceived by the people.
Table 10.1 Population Growth in the Surveyed Settlements
|Study area||Settlement||Total population||1970-1984 intercensal growth rate||Projected population|
Source: Based on 1960 and 1984 population census reports.
Table 10.2 Ethnic Composition of the Sample of Farmers Interviewed at the Study Sites in October 1993 (shown by percentage)
|Study area||Settlement||Twi||Kyerepony||Ayigbe/Ewe||Krobo||Other Akan||Non-Ghanaians|
Source: PLEC 1993 field study.
Amanase, Whanabenya, Sekesua and Osonson were founded in the early parts of this century by migrant cocoa farmers from Akuapem district in the case of Amanase, from the Siade/Shai area in the case of Whanabenya, and from Krobo country in the case of Sekesua and Osonson. Yensiso and Adenya probably existed as small Akuapem hunting and oil-palm growing hamlets before the founding of Amanase, Whanabenya, Sekesua and Osonson, but expanded after the introduction of cocoa there during the 1900s. Kokormu probably was a later creation by the Ayigbe and Ewe migrants who settled there, perhaps around 1950, for the purpose of food crop farming, which is now the leading economic activity of the forest-savanna zone inhabitants, including the migrants, who comprised mostly:
Others were the relatively few Kyerepong-speaking Akuapem concentrated in the Yensiso and Amanase areas, and other Akan-speaking people and non-Ghanaians found in the Yensiso area. The detailed distribution is shown in table 10.2.
Our estimate of the average population density per square kilometre for the whole forest-savanna zone is 161 or more in 1993. Table 10.3 shows the 1984 densities for the local council districts where the study areas were located. They ranged from 139 to 178 persons per square kilometre, compared to the national average of about 51. Since these figures are for 1984, they are likely to differ somewhat from the present situation. For instance, the Manya Krobo local council population stood at 140/km2 in 1970, compared to 108 in 1984, a decrease which, like decreases in other rural areas, most probably represents outmigration in response to environmental deterioration. However, on the whole, the population densities within the forest-savanna zone were expected to be on the increase in accordance with the general national trend.
Table 10.3 1984 Population Densities for Local Council Districts Where the Study Areas Were Located
|District||Study area||Population density for local council district|
|Akropong local council||Yensiso
|Manya Krobo local council||Sekesua (Sekesua, Osonson)||105||272|
|Suhum urban council||Amanase (Amanase, Whanabenya)||178||461|
Source: Ghana Statistical Services 1989.
The population factors analysed above have varying degrees of implication for the status of the environment. The increase in the absolute numbers of people is a major source of stress on the environment through farming and extractive activities. On the basis of the 1970-84 growth rates, the populations of Kokormu, Amanase and some other villages are likely to more than double by the year 2000, resulting in increased pressure on the already stressed land and other resources (table 10.1). The depopulation which some of the areas are likely to continue experiencing might not significantly alter the environmental degradation because of the severity of the damage already done and the lack of the corrective wherewithal in the affected rural areas.
As the quality of the environment declines, so do the yields, earning and living standards. In particular, the continuous cropping of the increasingly fragmented fields leads to land impoverishment and consequent low output. It is not surprising therefore that 25 per cent of the households could no longer adequately feed themselves with the produce from their farms. Significantly, the figure for Amanase, which showed the highest population growth rate among all the villages surveyed, was 45 per cent. These findings about the environmental effects of the population changes suggest the need for population control in conjunction with other mitigating measures.
The pressure exerted by population on the biophysical environment is transmitted in various ways, especially through the demand for products derived directly or indirectly from the environment. The demand originates from rural and urban areas within a country itself, and from other areas outside the country. We carried out surveys in rural markets at Adawso (near Yensiso), Sekesua and Amanase, in a preliminary attempt to determine the character of this demand on our study areas, particularly in terms of what is taken out and their destinations. The results are summarized in tables 10.4 and 10.5 and in figure 10.1.
Table 10.4 Types of Commodities Destined out of Adawso, Sekesua and Amanase Markets (percentages)
|Staple foods (cassava, plantain, yam, maize, cocoyam)||Vegetables, beans & condiments (tomato, garden egg, okra, pepper, kontomire, [cocoyam leaves])||Fruits (citrus, banana, avocado, others)||Processed foods (gari [grated fried cassava], kokonte items [dried cassava chips or flour], palm oil)||Other food (palm fruit, snails, fowl, sugar cane)||All food items||Miscellaneous (brooms,corn husks,baskets, dried plantain leaves)||Fuel (firewood, charcoal)|
|Top four commodities:|
|1. cassava||1. cassava||1. gari|
|2. tomato||2. citrus||2. cassava|
|3. palm fruit||3. pepper||3. citrus|
|4. maize||4. plantain||4. kontomire|
Source: Based on market surveys by sample in October 1993.
Table 10.5 Destinations of Commodities Purchased by Middlemen from Adawso, Sekesua and Amanase (percentages)
|Accra- Tema||Koforidua||Suhum||Agomenya||Mampong- Akuapem||Nsawam||Akropong Akuapem||New Tafo||Aburi||Asesewa||Total|
|Top four commodities destinations:|
|1. Accra-Tema||1. Accra-Tema||1. Accra-Tema|
|2. Koforidua||2. Agormenya||2. Suhum|
|3. Mampong-Akuapem||3. Kpone||3. Suhum|
|4. Afienya||4. Asesewa|
Source: Based on market surveys by sample in October 1993.
On the whole, food items, most especially unprocessed primary agricultural ones, led by cassava, comprised nearly 91 per cent of the commodities destined out of the three markets, which confirms the significance of farming as a factor in the environmental change. About 9 per cent of the commodities that were destined out consisted of other items, including firewood and charcoal, whose production contributes significantly towards the depletion of the forests.
On the average, 91 per cent of the commodities were destined for urban settlements,! most especially Accra-Tema, Ghana's largest settlement, a finding which is in general conformity with a previous observation with respect to the Sekesua market (Gyasi 1976). The remaining 9 per cent were destined for rural settlements which, like the urban destinations, were located within or near the forest-savanna zone (fig. 10.1). It is evident then that the demands of the urban centres are a significant source of stress on the forest-savanna environment. In the past, much of the production pressure placed on this zone originated from outside Ghana. It took the form of external demand for minerals and primary agricultural and forest products, notably palm oil, cocoa and timber.
There is little question that the main driving force behind the environmental change in the southern forest zone is population pressure. Rapid increases in the absolute numbers of people, their uneven spatial distribution, and the demands from urban centres within the country and from outside the country exert varying degradational effects on the biophysical resources of the zone. The threat to the environment is aggravated by unfavourable climatic trends. This underscores the need for population control, floral and faunal conservation programmes and other environmental rehabilitation measures, particularly through education.
1. An urban settlement is defined as a settlement having a total population of 5,000 or more, whilst those having less than 5,000 are considered rural (Central Bureau of Statistics 1984; Statistical Services 1989).
Central Bureau of Statistics. 1984.1984 Population Census of Ghana: Preliminary Report. Accra.
Gyasi, E.A. 1976. Population pressure and changes in traditional agriculture: case study of farming in Sekesua-Agbelitsom, Ghana. Bulletin of the Ghana Geographical Association 18: 68-87.
Statistical Services. 1989.1984 Population Census of Ghana, Special Reports on Localities by Local Authorities.. Accra.