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close this bookSustaining the Future. Economic, Social, and Environmental Change in Sub-Saharan Africa (UNU, 1996, 365 p.)
close this folderPart 5: Environment and development in Ghana
close this folderThe environmental impact and sustainability of plantations in Sub-Saharan Africa: Ghana's experiences with oil-palm plantations
View the document(introduction...)
View the documentIntroduction
View the documentOverview of the plantation system in the Sub-Sahara
View the documentThe evolution of plantations in Ghana
View the documentThe positive impacts of the plantations
View the documentAdverse environmental impacts and sustainability
View the documentConclusion
View the documentReferences

Adverse environmental impacts and sustainability

However, the question is whether the gains can be sustained. An answer was sought by examining the plantations' adverse impacts, particularly on the natural environment.

Traditionally, the natural environment, including the land, has constituted the basis of the farming, hunting, and gathering economies in the plantation areas. Consequently, the expropriation of over 16,000 ha of peasant lands for the plantations, with little or no compensation for the cottages, camps, and farms lost, together with various land-use or proprietary rights, could be expected to precipitate social resistance. This, indeed, had been the case, as illustrated by the dramatic refusal of the migrant Ningo farmers of Atobriso and Okaikrom to grant government and GOPDC officials entry into their acquired land. As in the case of land expropriated for the RISONPALM nucleus estate in Nigeria (Gyasi 1987,1990), other manifestations of the peasants' resistance had included: a group petition to the government and to the management of the plantations; threatened court action; pilfering of palm fruit from the plantations; and acts of sabotage, which had necessitated a tightening of security at considerable cost to the plantation companies. The insecurity engendered by the compensation factor partly accounts for the companies' inability to establish effective control over portions of their concessions used illegally by land-short local people, including squatter farmers.

But perhaps the most serious adverse effect has been the rapid transformation of the forest ecosystem and its resilient diversified ecologically based traditional economy into a vulnerable artificial monocultural system. Instability, risks, or uncertainties are inherent features of the natural environment, which the peasant farmers recognize. Traditionally, the peasants try to minimize these environmental risks, combat soil erosion, optimize utilization of the different soil nutrients, and enhance food security by intermixing crops of varying degrees of environmental sensitivity and different nutritional value, and by other forms of agricultural diversification and risk minimization. The resilient, diversified indigenous agriculture, modelled on the forest ecosystem and based on eco-farming principles borne out of the peasants' intimate knowledge of the natural environment, is being replaced by the risk-prone monocultural system, with devastating consequences for the forest ecosystem.

Of a sample of farmers, 47 per cent perceived a trend towards palm monoculture as a result of the activities of the plantation companies in their locality; 62 per cent of the farmers considered the monocultural trend desirable, because they saw the palm as lucrative, dependable, and a steadier income-generator owing to the high value placed on it, its robust character, and its bi-monthly fruiting habit. However, a significant 38 per cent of the farmers did not consider the trend towards palm monoculture desirable, primarily because it was leading to shortages of local staple foods, a problem also reported by the management of the plantations. A second reason was the vulnerability of the monocultural palm farms to insect pests and diseases (table 18.1), an agro-ecological problem most vividly demonstrated by the unusually massive and destructive insect invasion of the monocultural palm farms in 1986-1987. A third reason was the difficulty of marketing palm fruit and oil associated with poor marketing facilities for the increased output, and the higher production cost in Ghana, related to the less favourable moisture conditions and less effective radiation utilization by the palm (BOPP 1990), which has led to the growing premature felling of the palm trees for production of the local gin, akpeteshie. Other reported or observed adverse effects were:

deforestation, and the associated growing cost and scarcity of forest products such as "bush meat" (game), medicinal plants, and wood, an important constructional material and the basic fuel source;

the high cost, erratic supplies, and polluting effect of the agrochemicals used to boost palm yields and to control pests and weeds, especially in the large plantations;

environmental pollution by the palm fruit and palm oil effluents, a potentially rich source of organic fertilizer.

Although these reports or observations require further investigation, they nevertheless point to the environmental shortcomings of the system.

On the one hand, the plantation system, especially the nuclear estate version, appears attractive as a development strategy in the Sub-Sahara because of its ability to accelerate agricultural production and generate other important socio-economic benefits, including employment, income, agro-industrial growth, and modern infrastructure, especially in the rural areas. On the other hand, the system does not appear attractive because its vulnerable character and adverse effects on traditional landholding and land-use rights, on food and fuel security, and, above all, on the natural environment throw its sustainability into serious doubt.

Perhaps the plantation system might be rendered sustainable by encouraging its modification into smaller diversified farms on the basis of organic and other eco-farming and the principles of low external inputs that underpin proven sustainable systems such as modern agro-forestry and traditional African systems, notably:

the bush fallow system, which intermixes diverse crops amidst selected uncleared trees and bushes in the form of proto-agroforestry;

the more or less permanent farming system on compound land, which often integrates both livestock and assorted crops around the household or living compound (Benneh 1972; Benneh and Gyasi 1991; Gyasi 1992b; Kopke and Schulz 1992).

Table 18.1 Insect pests and diseases of the oil-palm

Scientific name Common name Category
Coelaenomonadera minuta (Coleoptera: Hispidae) Oil palm leaf miner Primary pest
Pimelophila ghasquieri (Lepidoptera: Pyralidae) African spear borer Primary pest
Temoschoita quadripustulata (Coleoptera: Curculionidae) Oil palm weevil Primary pest
Phynchophorusphoenicis (Coleoptera: Curculionidae) Red striped weevil Primary pest
Oryctes spp. (Coleoptera: Dynastidae) Rhinoceros beetle Primary pest
Latoia viridissima (Lepidoptera: Limacodidae) West African slug caterpillar Secondary pest
Zonoceros variegatus (Orthoptera: Acrididae) Grasshopper Secondary pest
Augosoma contaurius (Orthoptera: Dynastidae) N.A. Secondary pest
Adoretus umbrosus (Coleoptera: Dynastidae Rutelidae) N.A. Secondary pest
Schizonycha africana (Coleoptera: Nololunthidae) N. A. Secondary pest
Parasa viridissima (Lepidoptera: Limacodidae) West African slug caterpillar Secondary pest
Spodoptera litura (Lepidoptera: Noctuidae) N. A. Secondary pest
Phenacoccus spp. (Hemiptera: Coccoidea) Mealy bug Secondary pest
Pinnaspis marchali (Hemiptera: Coccoidea) Scale insect Secondary pest
Sufetula nigrescens (Lepidoptera: Pyralidae) Oil palm aerial root Potential pest
Metisa plana (Lepidoptera: Psychedae) Oil palm bag worm Potential pest
Leptonatada siostedti (Lepidoptera: Notodontidae) N. A. Potential pest
Monolepta apicicornis (Coleoptera: Chrysomelidae) N.A. Potential pest
Cercospora leaf spot

Source: Gyasi (1991).
N.A. = not available.

The principles underlying the native African systems have much to recommend them because they derive from intimate knowledge of the local environment, form an integral part of the traditional culture, and, as such, offer a strong basis for agricultural development. Other possibilities for improving the environmental impact and sustainability of plantations include the "i'th" or "n'th" row method whereby every second, third, etc. row in the plantation is reserved for crops other than the primary plantation crop. Another is the arrangement whereby the outgrowers and the smallholders devote a portion of their land to the industrial crop required by the nuclear estate mill and the rest to food or other crops. Others include the intermixing of the principal plantation crop with other crops.