AGRICULTURE IN URHOBOLAND

 

Urhoboland occurs in the drier landward part of the Niger Delta where crop farming assumes considerable importance. In contrast, the seaward part of the delta which is inhabited  by the Izons and the Itsekiris, is more swampy and is characterized by extensive creeks, on account of which fishing replaces farming as the dominant aspect of the rural economy. As with most parts of Nigeria, agriculture is the dominant aspect of the rural economy of Urhoboland.  About 70% of the population is engaged in farming. Given the heavy annual rainfall that exceeds 2500 mm, the main crops grown in Urhoboland are root crops such as yams and cassava and tree crops , especially rubber and oil palm. In this regard, the agricultural economy sharply contrasts that of the drier savanna lands of Nigeria where the cereals such as guinea corn and millet are the dominant crops produced.

 This brief write-up outlines the main features of agriculture in Urhoboland, highlighting the principal agricultural systems, constraints on agricultural production and the impact of agriculture on the environment. Ways of intensifying subsistence agriculture and ensuring sustainability in the long run are also considered.

 
AGRICULTURAL SYSTEMS

The main agricultural systems include shifting cultivation ( also known as rotational bush fallow), permanent cultivation and livestock production; the last mentioned being relatively unimportant, although a viable means of animal protein supplementation in an area where crop farming is the dominant feature of agriculture.

Shifting Cultivation

Shifting cultivation, also known as the rotational bush fallow, is characterized by impermanence of cultivation on the same site, with short periods of cropping alternating with longer periods of fallow during which the site is left uncultivated. A distinct feature of this system of farming is the rotation of fields. A farmer usually owns several plots or fields which he cultivates sequentially on a rotational basis. He cultivates a plot for a few years, usually about 1-3 years, and then abandons it temporarily when soil fertility declines. During cropping, soil fertility declines rapidly and since fertilizers are not applied to sustain yields, the farmer is forced to abandon the cultivated site after a few years and the land is allowed to regenerate fallow vegetation. The vegetation that  colonises an abandoned farm at the cessation of cropping is called fallow vegetation. It helps to restore soil fertility which declined during cropping. In some cases, farmers are forced to abandon  a cultivated site after a few years because of the problems of pests, crop diseases or because of the difficulties of coping with the  rapidity of weed growth after a few years of cultivation. In the past when land was still plentiful, a cleared site was usually cultivated for 1-3 years before being fallowed for a period of 3-10 years. Rapid population growth and the problem of land shortage have drastically reduced the amount of arable land in Urhoboland and farmers have reduced fallow periods considerably to 1-3 years and in some cases, continuous cultivation has emerged. It is important to point out right from the outset that shifting cultivation is not unique to Urhoboland, rather it is a pantropical system of agriculture that is widely practised in the humid and sub-humid tropics including large areas in South America, tropical Africa and Asia ( Nye & Greenland 1960).

 The main crops produced in Urhoboland using the system of shifting cultivation are mainly field crops such as cassava (Manihot esculenta), yams (Dioscorea spp.) maize (Zea mays) okra ( Hibiscus esculentus), cocoyam ( Colocasia esculenta) and occasionally plantain ( Musa sp.).   Land to be cultivated is cleared towards the end of the dry season, usually between November and February. In the past, old fallow vegetation and even forest is cleared. Nowadays, forests are rare and farmers clear fallow vegetation dominated by forbs especially, Chromolaena odorata and a few scattered trees. The cut slash of fallow vegetation is allowed to dry before being burnt  to release ash to fertilize the soil, prior to cultivation at the beginning of the wet season in about March. Several decades ago when forests existed in Urhoboland, the large trees are usually left standing when a site is cleared for cultivation. Such trees are subsequently killed by burning them. Usually, when a site is cleared, the smaller trees are cut using a machete at a height of about one metre above the ground, leaving their stumps in the ground to help facilitate tree regeneration during the fallow period and to help conserve the soil by checking soil erosion. In the past when yam cultivation was widespread in Urhoboland, the crowns of small trees such as Baphia nitida, Anthonotha macrophylla and Dialium guineese  were pruned off and the standing stems of the trees used for training yam vines. Owing to decline in soil fertility due to the shortening of the fallow period, the cultivation of yams is no longer important in Urhoboland. Cassava is now the main crop produced. Yams, cassava, maize, okra and pepper are usually intercropped on cultivated plots which rarely exceed 0.5 hectare. Usually maize is the first crop to be harvested while cassava is harvested last. Soil nutrients decline rapidly during cultivation due  to soil erosion, leaching, nutrient uptake by cultivated crops and diminished supply of litter to the soil which is inadequate to match the rate of humus decomposition in the soil ( Nye & Greenland 1960).

When the cultivated site is left to fallow after a few years of cultivation, the site is quickly colonized by herbaceous plants such as Tridax procumbens, Euphorbia hirta, Panicum maximum and forbs, especially Chromolaena odorata. These weeds invade the farmland before cassava is harvested. These herbaceous weeds and forbs are replaced by woody plants such as Sterculia tragacantha, Dialium guineense, Anthonotha macrophylla, Harungana madagascariensis , Ficus exasperata and Rauvolfia vomitoria after about 5-7 years. Harungana madagascariensis is now becoming rare in fallow vegetation in Urhoboland presumably due to soil fertility decline, consequent on shortening of the fallow period, and frequent cultivation. These woody plants help to replenish soil organic matter and nutrient status by protecting the soil against soil erosion, enhancing humus and nutrient accretion in the soil through litterfall and mineralization and by recycling nutrients leached into the subsoil back to the topsoil. The process of vegetation development and soil fertility restoration in rain forest fallows in south western Nigeria has been documented by Aweto (1981a,b).

The system of shifting cultivation has undergone intensification during the past two or three decades, mainly in response to acute land shortage. The problem of land shortage has been further exacerbated by the widespread growing of  a perennial tree crop, rubber, particularly since the 1950s. Intensification of shifting cultivation in Urhoboland merely involved the reduction or elimination of the fallow period without resorting to the use of fertilizers or  integration of soil fertility enhancing trees such as Senna siamea or other legumes into farms. In areas around large towns such as Ughelli and Warri, continuous cultivation without using fertilizers is emerging. Even in the more fertile soils  of south western Nigeria derived from basement complex rocks, Aweto et al (1992)  observed that continuous cultivation of cassava intercropped with maize led to soil nutrient and organic matter decline. In the less fertile soils derived from sedimentary rocks in Urhoboland, continuous cultivation without fertilizer application is likely to have  a more drastic effect on soil nutrient status in view of the fact the soils naturally have very low weatherable mineral reserves. It is very probable that continuous cultivation has resulted in declining yields which may have stabilized at very low levels. As pointed out earlier, the widespread shift from the cultivation of yams to a less demanding crop- cassava- is largely in response to the elimination or shortening of the fallow period and the attendant decline in soil fertility. In view of the high cost of imported fertilizers and the adverse environmental effects such as eutrophication that would result from the application of chemical fertilizers, the adoption of agroforestry appears to hold greater promise for the intensification of shifting cultivation in Urhoboland.

Agroforestry is the practice of integrating trees into farmland in order to help maintain soil fertility and possibly help to raise the level of agricultural productivity. Trees help to maintain soil fertility by adding litter to the soil, improving soil physical status while their roots absorb nutrients from the subsoil and from the weathering zone of rocks below the ground and subsequently recycle such nutrients to the topsoil ( Young 1997). Presently, the only tree that Urhobo farmers selectively protect and integrate into their farms is the oil palm ( Elaeis guineensis) which is the main source of vegetable oil in the forest zone of West Africa. The oil palm is selectively retained on the farm because of its economic importance, a practice which has led to the emergence of oil palm groves. Oil palms also feature prominently in cultivated plots of cassava, maize, cocoyam and other field crops. Although, the retention of oil palms in cultivated arable land in Urhoboland is agroforestry, the beneficial value of the tree is largely restricted to protecting the soil against erosion. Aweto & Ekiugbo (1994) have observed that oil palms tend to deplete soil nutrients due to long term nutrient immobilization in the trees and the harvesting of palm fruits which constitute a drain on soil nutrient capital. In  addition to the palm, it would be necessary to integrate other tree species especially those that improve soil fertility into farmlands in order to enhance sustainability in the long run. The tree, Albizia adianthifolia, has been reported by Prinz (1986) to improve soil organic matter, exchangeable calcium, magnesium, cation exchange capacity and available phosphorus of soil under its canopy in Cameroon. Albizia adianthifolia is one of the few surviving trees in bush fallow vegetation in Urhoboland.; most trees having been killed as a result of frequent burning, prior to cultivation. Although, the tree has no economic value apart from serving as a source of fuelwood, it is necessary for farmers to selectively protect it and even plant it in their farmlands in order to enhance organic matter and nutrient build-up in the soil and improve soil fertility in Urhoboland in the long run. Other trees such as Newbouldia laevis, Anthonotha macrophylla, Dialium guineense and even fruit trees  such as Maesobotrya barteri and Chrysophyllum albidum are likely to have beneficial effects on soil fertility if numerous isolated trees are integrated into farms. It would be necessary to prune the branches of trees integrated into farmlands in order to minimize the shading of crops which would reduce crop yield. Also, the pruned branches, especially young leafy twigs, should be returned to the soil as mulch and allowed to decompose in situ in order to enhance nutrient recycling to the topsoil for the benefit of cultivated crops.

Permanent Cultivation

Permanent cultivation is used in this context to refer to the antithesis of shifting or discontinuous cultivation.  Permanent cultivation in Urhoboland involves the continuous cropping of little patches of land around or near houses in rural areas and the cultivation of perennial tree crops such as para rubber (Hevea brasiliensis) and the oil palm (Elaeis guineensis). The cultivated patches adjoining houses in rural areas are fertilized regularly using household refuse, including ash, yam and cassava peels and food remnants. They are very small, rarely exceeding 0.1 hectare and should be more be more appropriately referred to as home gardens.

Home gardens

As with shifting cultivation, the practice of cultivating patches of land near dwellings is not unique to Urhoboland.  Home gardens have been reported for other parts of the tropics, especially Asia and Africa by Landauer & Brazil (1990). Plantains (Musa paradisiaca) and bananas (Musa sapientum ) are the main crops grown in home gardens, the former being overwhelmingly dominant. Plantains are self-propagating by means of suckers and there is no need for replanting once the first crop is well established. A few pawpaw (Carica papaya) trees are occasionally a feature of home gardens. Also, a few isolated trees of coconut ( Cocos nucifera), bitterleaf tree (Vernonia amygdalina) and a few orange (Citrus sinensis) trees are planted at the back of the house but these are not integrated into the plantain garden to form a more floristically diverse and multi-storied home garden that would ensure  a more efficient cycling of nutrients in the agroecosystem. Occasionally, yams are planted at the back of homes in sites previously used for dumping refuse. The enhanced nutrient status of such sites ensures that yams thrive well. At the outskirts of settlements, especially villages, where houses are widely spaced, it is usual nowadays for people to plant maize intercropped with cassava in home gardens. A few fruit trees such as mango (Mangifera indica) avocado pear (Persea gratissima) and occasionally guava (Psidium guajava) and some isolated palm trees may constitute the tree flora of such home gardens. Essentially, home gardens supplement food and fruit supplies from farms that are far from the settlement. Owing to rapid population growth and the attendant process of conversion of agricultural to residential land use, the significance of home gardens as dietary supplements has diminished considerably during the past two decades or so.

Tree Crops

Although, tree crops such as guava, citrus and mango are grown in Urhoboland, they are insignificant compared to oil palm and rubber which are the dominant tree crops.  The oil palm is one of the most important indigenous trees in the forest zone of West Africa. In Urhoboland, the palm is a source of vegetable oil, the fibres and hard shells of the fruits are used as fuel for cooking and heating, and the fronds for making brooms and baskets. The tree is also tapped for wine. Several decades ago, palm oil was the main fuel used for lighting homes prior to the importation of petroleum products. In the past, oil palms were not planted by farmers. The palms grew and still grow wild in farmlands, bush fallow vegetation and in clearings. It is rare for the oil palm to grow in dense primary forests (Irvine 1969) . Farmers protect palms growing on their farms but such palms are communally owned and exploited. The farmer on whose farmland oil palms grow, does have an exclusive right to their exploitation. The community regulates when palms can be exploited and how many bunches of palm fruits can be harvested by each male farmer. Palm fruits are traditionally crushed in special wooden troughs and processed for oil while the hard shells are cracked mechanically to obtain kernels which  also yield oil. In the past, palm oil and kernels were important agricultural exports of Nigeria, particularly in the 1950s and early 1960s when Nigeria was the leading exporter of palm produce in the world. However, owing to neglect of agriculture due to enormous revenue earned from petroleum in the 1970s, palm produce production in Nigeria declined considerably and the country became a net importer of vegetable oil, which was usually of higher quality than oil produced by indigenous farmers, including Urhobo farmers. As a result of massive devaluation of the Nigerian currency in the 1980s and 1990s  due to the introduction of the Structural Adjustment Programmme, most Nigerians could not afford to buy imported vegetable oil. This stimulated local demand for palm oil and today, farmers in Urhoboland have established holdings of improved varieties of oil palm in addition to exploiting groves of wild palms. The proportion of palm produce obtained from planted palm holdings in Urhoboland will increase over time as more people, hopefully, embrace planting of improved palm seedlings and as most wild palm groves become old and less productive.

The most widely grown tree crop in Urhoboland is an exotic, para rubber (Hevea brasiliensis) . There are a number of indigenous rubber-producing trees in Nigeria’s rain forest zone prior to the introduction of para rubber. Such native rubber producing species include Funtumia elastica and Funtumia africana. Sustained production of latex could not be guaranteed from wild trees that are scattered about in the forest.  Many wild indigenous rubber trees were not tended and were quickly killed, mainly as a result of inappropriate tapping techniques . Hence, an exotic rubber tree species that can be easily  established in pure stands was introduced to replace wild indigenous rubber yielding trees. Most of the planting of rubber in Urhoboland occurred  between 1950 and 1965 and by the latter date, up to 75% of the arable land in Urhoboland is under the crop ( Udo 1970). The size of the rubber plots of individual farmers rarely exceed 5-10 hectares. The plots of farmers are contiguous, with no visible demarcations between them. Consequently, rubber trees are the most conspicuous feature of the rural landscape, with rubber plots stretching along both sides of roads, sometimes uninterrupted for kilometers. Rubber trees are tapped daily and the latex processed into rubber sheets or lumps. In the past, most of the produce is exported but is now mainly utilized  locally in shoe, tyre and mattress factories.

Rubber trees deplete soil nutrients over time as a result of nutrient uptake and storage in the trees and due to nutrient loss from the trees via the latex collected ( Aweto 1987a). In most parts of Urhoboland, rubber trees have become old and latex yield has declined  considerably, mainly on account of old age of trees, declining soil fertility and bad tapping techniques. Since rubber provides  rural employment and helps in some measure to stem rural-urban migration, it would be necessary to rehabilitate old and unproductive rubber plots.

A number of indigenous fruit trees such as Irvingia gabonensis, Chrysophyllum albidum and Maesobotrya barteri are not cultivated and are gradually becoming extinct. Irvingia fruits are in great demand, especially the dried seeds locally known as “ogbono” that the Igbo people relish. The sustained supply of the fruits of Irvingia gabonensis and other forest fruits is uncertain as most forest trees have been destroyed as a result of widespread deforestation in Urhoboland. Valuable fruit trees such as Irvingia should be grown in farmlands and possibly in  plantations for more effective management and in order to ensure supply of such fruits in commercial quantities. Fruits can be commercially processed for juice or canned and this could provide the basis for the establishment of agro-based industries that process indigenous fruits of the rain  forest zone. The fruits of Maesobtrya barteri can be used to produce fruit drink that is similar to black currant drink now imported into the country. The establishment of plantations of these fruit trees and of the allied agro-based industries will, hopefully, provide employment for Urhobo youths and help to stem the tide of brigandage and youth  restiveness in the northern part of the Niger delta.

LIVESTOCK PRODUCTION

Given the natural rain forest vegetation, livestock production is relatively unimportant  compared to crop farming. A few poultry are usually kept in rural areas as sources of meat. The keeping of poultry for the production of eggs is unimportant in rural areas. However, in the outskirts of large towns such as Warri, Ughelli and Sapele, commercial poultry production assumes considerable significance and poultry are reared  for the production of both meat and eggs to meet the  requirements of urban dwellers with  higher levels of income. Local unimproved varieties of poultry are reared in rural areas under the free range system. Chicken scavenge for food, feeding on insects, food remnants thrown into dump sites behind houses and plant materials. Local chicken produce very little meat compared to those reared in commercial poultry farms.

A few goats and sheep and occasionally pigs are also kept  by Urhobo people in villages as a sideline to crop farming. They are usually allowed to roam about in villages, scavenging for food, and they often damage crops in cultivated plots near settlements. Occasionally, goats and sheep are kept in enclosures and fed with peels of cassava, plantains and yams, supplemented with grass and browse supplied by the farmer. There is very little or no integration of livestock and crop farming in Urhoboland, unlike in the drier savanna of northern Nigeria where livestock are allowed to graze on farmlands during the off-farm season and their droppings help to fertilize the soil.

IMPACT OF AGRICULTURE ON THE ENVIRONMENT

Perhaps, the most widespread and striking impact of agriculture in Urhoboland is the pervasive replacement of the natural, floristically diverse rain forest ecosystem with monocultures of rubber farms and other agricultural ecosystems of field crops such as cassava, maize and yams intercropped. The agroecosystems that replace the natural rainforest are less diverse floristically and are much less complex structurally than the original rain forest. Although, rubber “plantations” which constitute the most widespread agricultural land use in Urhoboland, appear superficially similar to a forest, they are less efficient than the native rain forest in terms of nutrient cycling and soil conservation. As pointed out earlier, rubber trees tend to deplete soil nutrients over time. As with other exotic single-species tree plantations in the rain forest zone of West Africa, the establishment of rubber plots destabilizes the efficient cycling of nutrients in the natural rain forest ecosystem. This is mainly because single –species tree plantations usually immobilize soil nutrients faster  and return less nutrient to the soil through litterfall and mineralization and rainwash than the natural rain forest (Aweto, 2001). Widespread conversion of rain forest into single-species tree plantations is ecologically unsound as the long term sustainability of such tree monocultures cannot be guaranteed, except, perhaps, with generous application of fertilizers. The conversion of rain forest into monocultures of indigenous oil palms also, have a similar effect of destabilizing the  “closed” or “tight” nutrient cycle of the natural rain forest.

A major problem associated with agriculture as pointed out above is the loss of biodiversity . Burning the dried slash of cleared vegetation to release nutrients into the soil, is an important aspect of soil fertility management during cropping, especially under the system of shifting  cultivation.  As a result of frequent burning associated with cultivation, farmlands lack many woody species. Trees such as Harungana madagascariensis, Antiaris toxicaria, Milicia (Chlorophora) excelsa, Pentaclethra macrophylla  which were common in Urhoboland three or more decades ago, are becoming rare. These and other tree species do not regenerate fast, as they used to do. This is mainly because of the non-availability of seed-bearing parent plants due to widespread deforestation and conversion of rain forest into plantations or farmland. Deforestation in Urhoboland has not only caused loss of plant species but also of wildlife. Destruction of forests results in loss of habitats and sources of food for many wildlife species. Wildlife  such as elephant (Loxodonta africana), lion (Panthera leo) chimpanzee (Pan troglodytes), leopard (Panthera pardus) and hippopotamus (Hippopotamus amphibious) have become extinct in Urhoboland.

The problem of soil fertility impoverishment as a result of shortening of the fallow period or conversion of rain forest into plantations of rubber or oil palm has been referred to. Erosion, which is mainly responsible for silting up of rivers such as the Warri River, deserves mentioning here. Usually, rubber holdings extend to the banks of rivers. Rubber trees are deciduous. They  shed  their leaves during the dry season in about January or February (Irvine 1969). Rubber plots are usually burnt towards the end of the dry season to dispose of their undergrowth and facilitate movement of rubber tappers. The first few rains following the burning of rubber holdings are very erosive as rubber ‘plantation’ floor is bare. These rains cause accelerated erosion and the sediments generated are washed by runoff into rivers. This causes the rivers to silt up gradually as a result of sedimentation. In addition, cultivation of field crops such as cassava and maize contribute substantially to erosion and runoff as these crops do not provide adequate protection for the soil, unlike the native rain forest.  

 CONSTRAINTS ON AGRICULTURE

The institutional and socio-economic constraints on agriculture in the developing countries are well known and will not be considered here. This section, therefore, concentrates primarily on environmental constraints which hinder agricultural production in Urhoboland. A major constraint on agriculture in Urhoboland is the soil which is inherently of low fertility. As pointed out earlier, the soils are predominantly sandy, with sand accounting for up to 90% of the mineral fragments in the topsoil. On account of their sandy nature the soils have a very low nutrient holding capacity , as evident in their low cation exchange capacity which may be as low as 4 cmol/kg of soil or lower. The organic matter content of the soils  is also low, even under rain forest vegetation. This, again, reflects the sandy nature of the soils and the heavy rainfall which leaches humus and nutrients from the soil. The soils are also acidic, mainly due to the pronounced leaching associated with heavy rainfall experienced in Urhoboland. The pH of the soil may be as low as 4.5 or lower in the topsoil. The implication of the pronounced acidity of the soils is low base saturation which will further exacerbate the problem of low nutrient availability resulting from low cation exchange capacity.

Another problem associated with agriculture is frequent flooding. The ground water table is high, rising to or near the ground surface during the wet season. This usually leads to flooding, especially after a spell of intense and heavy downpours. Crops such as cassava and guinea yam have to be harvested before maturation as a result of flooding. The grassland patches of Urhoboland contain grasses such as Panicum maximum, Hyparrhenia  sp.and the legume, Centrosema pubescens, which are suitable for feeding livestock. Aweto (1987b) suggested that ranches of  sheep, goats and humpless cattle that are indigenous to the rain forest zone should be established in the savanna patches to utilize their grazing  resources. Flooding during the wet season appears to be a major constraint hindering the utilization of the savanna vegetation of Urhoboland for grazing. Presently, the savanna areas  are used for grazing cattle from the drier savanna lands of northern Nigeria during the dry season. Also, on account of their proneness to flooding, the heavier textured soils derived from shale are unsuitable for growing the main staple crops of the Urhobo people, especially guinea yam and cassava. Such clayey soils are however, used for growing oil palm and rubber which appear to tolerate waterlogged soils. It is not clear however, whether prolonged waterlogging and the attendant problem of poor soil aeration substantially reduce the productivity of the tree crops. 

Although, Urhoboland is suitable for growing tree crops on account of the long growing season and heavy rainfall combined with deeply weathered soils, the soils are prone to nutrient depletion, especially when used for growing tree crops which make long term demands on soil nutrients. The problem of nutrient depletion appears to have been worsened by the fact that the soils are deeply and intensely weathered. Consequently, they lack adequate weatherable mineral reserves to replenish nutrients taken up by crops and subsequently lost from the ecosystem via harvested crops or other products such as latex in the case of rubber. Mainly on account of their low weatherable mineral reserves, the soils are plagued by the problem of declining yields when used for intensified production of field crops with reduced or no fallows and little or no fertilizer application. The application of substantial quantities of fertilizers by the farmers in the near future appears unlikely in view of the high cost of imported fertilizers and the inability of most farmers to obtain locally produced fertilizers. The point needs be made here that, in view of the low cation exchange capacity of the soils, substantial quantities of applied fertilizers will be leached from the soil and become unavailable for cultivated crops.

Rural-urban migration, accentuated by the acquisition of western education and values by Urhobo youths, has resulted in shortage of farm labour and declining farm productivity. In several cases, oil spills and related  disasters have resulted in loss of farmland and forced migration of people to towns such as Warri, Sapele and Ughelli to further aggravate socio-economic problems in these towns. Another related problem is that of gas flaring which has also robbed the people of valuable farmland. Around each gas flare site is an island of scorched and unproductive land - the product of excessive evapotranspiration and thermal decomposition of soil organic matter due to excessively high temperatures in the immediate vicinity of the gas flare site.

CONCLUSION

This paper advocates the development of traditional agriculture through agroforestry which will not only help to maintain and possibly improve soil fertility to ensure sustainability of traditional agriculture but would also help to provide fuelwood to rural farmers. Decline in soil fertility in Urhoboland is partly due to neglect of the cultivation of leguminous crops, especially cowpea and groundnuts. Both crops are good cover crops and also serve as green manure. In addition to reducing soil erosion, they help to replenish soil nitrogen (Irvine, 1969; Onwueme & Sinha 1991). The reintegration of cowpea into farmlands and the intercropping of groundnuts with maize will help to improve soil nitrogen levels.  This measure together with the practice of agroforestry will help to improve soil nutrient levels ( in  spite of the intensification of agriculture) and help to reduce probable future reliance on inorganic fertilizers which may have undesirable effects such as pollution of surface and underground water resources.

It will be necessary ,also, to develop plantations of indigenous trees such as Irvingia gabonensis, Chrysophyllum albidum, Maesobotyra barteri and Spondias mombin which can hopefully serve as the basis for local raw material based industries such as fruit canning and the manufacture of fruit drinks and jam. In order to ensure the long term sustainability of such plantations, it would be necessary to establish the plantation tree species between strips or stands of other forest trees in order to enhance biodiversity and make nutrient cycling more efficient. The establishment of cassava-processing and starch manufacturing factories could further enhance the development of arable agriculture and possibly the export of cassava products, if the policy of cassava development is vigorously pursued at the national level.

Finally, the problem of youth restiveness in the Niger delta cannot be solved  by the deployment of troops by government to the area. Unemployed youths, who periodically disrupt oil production in the Niger delta, should be gainfully employed through the development of fishing industry, agriculture, establishment of agro-based industries and petrochemical industries. The need to provide gainful employment for unemployed youths, and hopefully, reduce the problem of youth restiveness in the Niger delta, underscores the imperative of developing agriculture and industries in the region.

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