Human Ecosystems: Sangana in Akassa
and low tide marks, in the protected lagoon behind the island. This is an ecosystem where alluvium and organic matter caught by the mangrove roots, in addition to the biomass created by the mangrove trees themselves, create their own medium. The dominant mangrove species is the Red Mangrove, Rhizophora racemosa, with its characteristic stilt and aerial roots, growing in such a tangle that none of the trees can grow taller than 10m, substantially below their maximum potential of 40m. Also, where the high tide is at its most shallow, we see the mangrove species Avicennia which does not have stilt roots but throws upon a carpet of breathing peg-roots around its base.
The animals of the natural ecosystem will have included many of the large mammals and reptiles still found in refuges in Southern Nigeria. There will have been a wide range of bird species because of the proximity of the rivers and the sea. Also a profusion of insects, and other arthropods including a wide range of crabs, and molluscs but, mirroring the plants, with a lower species diversity than in the rainforest further North.
19.5 NATURAL AND VIABLE SOCIETY
We assume that at some very early date, there were humans on the relatively accessible Sand Barrier Islands and like Botem-Tai it was with the advent of viable society in the area, at least 5000 years ago, that the natural ecosystem of Akassa would have begun to be substantially altered: the very accessibility of the Niger Delta estuaries and their abundance of fish would have made them especially attractive to human activity.
Akassa will have been influenced by early groups of people moving through the numerous protected and interlinked creeks and lagoons inland that stretch from the Volta Delta to the Bonny Estuary. Today, Akassa is settled by Ijo people who separated from other Ijo groups about 1000 years ago and moved Westwards from the Brass Estuary, so that Otuo Island (Map 10), in the Sangana Estuary, is the most Westerly point of the Akassa dialect of the Nembe-Ijo language. Settlements favoured the East sides of the estuaries because the West sides have mangrove forest and the Atlantic coast is too windy.
The Sangana and other Akassa people have always been fishermen as opposed to farmers or even hunters. Moreover they would have been involved in fish and salt trade North and into the interior of Africa. This trade will have been extended by their inevitable contact first with European traders from the 15th and 16th centuries onwards, although the Sangana River is too shallow to have been a major trading centre. The impact of the slave trade was felt throughout the region and although there was a small slave loading point at Kongho on the Nun Estuary, the major slave-trading corridors were to the West (Benin and Warri) and the East (the Bonny River).
The palm oil trade, which grew strongly after the middle of the 19th century, had the greatest long-term influence on Akassa and a large part of the population concentrated on the production of palm oil and palm kernel, at first for local traders, and later for the Royal Niger Company (later the United Africa Company - U.A.C.) which established as a major trading centre at Akassa (Bekekiri) towards the end of the century. This lasted until U.A.C. closed in 1960 when production stopped immediately, for lack of a market, and fishing became the primary occupation once more.
The high demand for oil palm products up to 1960 was probably the greatest incentive that the Akassa people had ever had for changing their environment, but this was mitigated by the fact that the palm was growing naturally and because Akassa is not suitable for large-scale plantation agriculture. The present pattern of land-use is less intensive, now that people have returned to fishing, than it was in the 1950s.
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