Bonny River Research Articles

Heavy metal profiles in various matrices of the Bonny/New Calabar River Estuary, Niger delta, Nigeria

A study of the concentrations of Ca, Mg, K, Zn, Pb, Cd, Co, Cr, Cu, Fe, Ni and Na in the sediment, sea water, fish and crab of the Bonny/New Calabar River Estuary in Niger Delta, Nigeria was carried out using atomic absorption spectrophotometer A-100 for two consecutive years. The contamination levels of the respective metals varied between 2011 and 2012and the range of mean values for all metals in mg/kg were presented along with variations at statistically significant level (P <0.05) between the two years studied. Only K, Zn and Co exhibited variation in their concentrations in water samples between the two years at a statistical significant level (P <0.05) probability. In sediment, only Cr varied between the two years at a statistically significant level (P = 0.05). All metals concentrations were higher in sediment than in water samples.Bioaccumulation factor (BF) indicated a more potent source of metals from sediment than water with organisms accumulating Zn, Fe and Ni in the magnitude of 10, 6 and 5 times more from sediment than from water. Some metals were more accumulated in fish than crab and vice versa. The evidence of elevated levels of heavy metals in sediment and bioaccumulation in biota in the studied area may poise a wanton threat to the health of inhabitants whose diet is predominantly fish. This calls for regular monitoring to avert potential public health problems arising from consumption of metals in seafood. Keywords: Heavy metals, Matrices, bioaccumulation, Bonny River, Niger Delta, Nigeria.

English

Analysis was carried out on the sediment of Bonny River and creeks around Okrika in order to determine the concentrations of organic matter, lead, nickel, vanadium and cadmium as well as their probable sources and diagenesis. Samples for trace metal analysis were prepared by acid digestion and analysed by atomic absorption spectrophotometry. Organic matter content was determined by the method of Walkey and Black. Mean concentrations (µg/g, dry wt) of trace metals were: Pb(23.22 ± 13.43), Ni (57.19 ± 16.93), V (0.06 ± 0.05), Cd (0.24 ± 0.32) while organic matter (% dry wt) were:TOC(1.14 ± 0.40) and TOM(1.990 ± 0.70) and revealed anthropogenic trace metal enrichment. The large standard deviations indicate temporal and spatial variations due largely to anthropogenic waste input. There was a weak association for Pb/organic matter (/r/=0.58, p<0.01) in the wet season suggesting a common source, most likely from land-derived wastes brought in by runoff water.   Key words: Organic matter, trace metals, anthropogenic enrichment, Bonny River.

Bioaccumulation of Trace Metals in Shellfish and Fish of Bonny River and Creeks around Okrika in Rivers State, Nigeria

Lead, nickel, vanadium and cadmium were determined in fish and shellfish muscles, to assess contamination levels and identify bio-indicators. Vanadium was not detectable. Lead and cadmium were slightly above legal limits used in South East Asia, but lower than those of Australia and New Zealand. Higher contents of nickel, cadmium and lead in Pachymelania aurita and Crassostrea rhizophorae, lead in Mugil cephalus and cadmium in Periophthalmus koelreuteri, mark these species out as possible bio-indicators for the three metals in aquatic systems. Patterns of bioaccumulation seem to suggest that biophysiological and ecological characteristics influence bioaccumulation of trace metals in fish and shell fish.

Mineral and Heavy Metal Contents of some Shellfish in Bonny River, Rivers State, Nigeria: Public Health Implication

Background: Shellfish serve as sources of food nutrients to the consumers and provide means of livelihood, especially to riverine people. As much as important these values are, consumption of shellfish can also present health hazards to consumers, especially if the water where they live is contaminated with industrial wastes. The level of minerals and heavy metal content of shellfish from Bonny River in Niger Delta region of Nigeria has not been fully explored. Objective: This study was aimed at providing public health information on mineral and heavy metal contents of shellfish from Bonny River and compared the values with Provisional Tolerable level set by the Joint FAO/WHO Codex Committee on Contaminants in Foods. Materials and Methods: This was a descriptive and analytical study. Randomly selected samples of the five most commonly consumed fresh shellfish from Bonny River, which included prawns, crabs, periwinkles; oysters and cockle were purchased from local sellers in all the riverside markets. Standard methods of analysis, using the AOAC were adopted. Selected minerals and heavy metals content were determined using Flame Photometer and Atomic Absorption Spectrophotometer. Data were analyzed using frequency counts and student t-test for inferential statistics. Results: The ranges of minerals and heavy metals contents from all the samples were: sodium 178.6-280.5mg/100g, potassium 399.5-600.7mg/100g, calcium 8.0-9.2mg/100g, magnesium 4.7-5.1mg/100g, iron 1.4-1.6mg/100g, zinc 5.9-6.5mg/100g and chromium 0.5-0.6mg/100g; whereas the range values of heavy metals include: arsenic (0.04-0.10mg/100g), lead (0.22-0.33mg/100g), mercury (0.04-0.08mg/100g) and cadmium (0.07-0.10mg/100g). The concentration of analyzed heavy metals exceeded the permissible international standards, with the exception of cockles, which did not exceed the maximum level of cadmium. High levels of heavy metal in the flesh of these shellfish may be linked with the level of these metals in Bonny River. Conclusion: These findings signify potential public health problem for the consumers. Awareness should be created through community-based health education approaches on dangers associated with the consumption of shellfish from this river.

Bioreactor-based bioremediation of hydrocarbon-polluted Niger Delta marine sediment, Nigeria

Crude oil-polluted marine sediment from Bonny River loading jetty Port Harcourt, Nigeria was treated in seven 2.5 l stirred-tank bioreactors designated BNPK, BNK5, BPD, BNO3, BUNa, BAUT, and BUK over a 56-day period. Five bioreactors were biostimulated with either K2HPO4, NH4NO3, (NH4)2SO4, NPK, urea or poultry droppings while unamended (BUNa) and heat-killed (BAUT) treatments were controls. For each bioreactor, 1 kg (wet weight) sediment amended with 1 l seawater were spiked with 20 ml and 20 mg of crude oil and anthracene which gave a total petroleum hydrocarbons (TPH) range of 106.4–116 ppm on day 0. Polycyclic aromatic hydrocarbons (PAH) in all spiked sediment slurry ranged from 96.6 to 104.4 ppm. TPH in each treatment was ≤14.9 ppm while PAH was ≤6.8 ppm by day 56. Treatment BNO3 recorded highest heterotrophic bacterial count (9.8 × 108 cfu/g) and hydrocarbon utilizers (1.15 × 108 cfu/g). By day 56, the percentages of biodegradation of PAHs, as measured with GC–FID were BNK5 (97.93%), BNPK (98.38%), BUK (98.82%), BUNa (98.13%), BAUT (93.08%), BPD (98.92%), and BNO3 (98.02%). BPD gave the highest degradation rate for PAH. TPH degradation rates were as follows: BNK5 (94.50%), BNPK (94.77%), BUK (94.10%), BUNa (94.77%), BAUT (75.04%), BPD (95.35%), BNO3 (95.54%). Fifty-six hydrocarbon utilizing bacterial isolates obtained were Micrococcus spp. 5 (9.62%), Staphylococcus spp. 3 (5.78%), Pseudomonas spp. 7 (13.46%), Citrobacter sp. 1 (1.92%), Klebsiella sp. 1 (1.92%), Corynebacterium spp. 5 (9.62%), Bacillus spp. 5 (9.62%), Rhodococcus spp. 7 (13.46%), Alcanivorax spp. 7 (13.46%), Alcaligenes sp. 1 (1.92%), Serratia spp. 2 (3.85%), Arthrobacter spp. 7 (13.46%), Nocardia spp. 2 (3.85%), Flavobacterium sp. 1 (1.92%), Escherichia sp. 1 (1.92%), Acinetobacter sp. 1 (1.92%), Proteus sp. 1 (1.92%) and unidentified bacteria 10 (17%). These results indicate that the marine sediment investigated is amenable to bioreactor-based bioremediation and that abiotic factors also could contribute to hydrocarbon attenuation as recorded in the heat-killed (BAUT) control.

Size composition, growth, mortality and yield of Alectis alexandrinus (Geoffory Saint-Hilaire) in Bonny River, Niger Delta, Nigeria

A twelve month study on the size composition, growth, mortality and yield of Alectis alexandrinus revealed a length range of 11.5 - 33.8 cm (standard length). Employing the length frequency method in the FISAT II package gave the following results for the Von Bertanlanffy growth parameters: L
= 35.23, K = 0.680, to = 0.3214 and  = 2.926. The total mortality (Z) was 2.47, natural mortality (M) 1.39 and fishing mortality (F) 1.08.The relative biomass per recruit (knife edge selection) was Lc/ L
= 0.05, E10 = 0.355 and E50 = 0.278. Although the exploitation rate (E) was 0.44 the Emax was 0.421 indicating moderate exploitation of the fish in Bonny River. There is room for increased effort in the fisheries.

Distribution of Lead and total Hydrocarbon in Tissues of Periwinkles (Tympanotonus fuscatus and Pachymelania aurita) in the upper Bonny River, Nigeria

The concentrations of lead and total hydrocarbons in the tissues of the periwinkles Tympanotonus fuscatus and Pachymelania aurita from the upper Bonny River were determined. The highest mean values of leadand total hydrocarbons were 9.45ìg/g and 1242.19ìg/g respectively. The results showed higher concentrations of lead and hydrocarbons in the creeks than in the open river. The concentrations of lead and total hydrocarbons measured at the control site were lower than the concentrations measured at the study sites. The concentrations of Pband THC were generally higher in the shells than in the tissues of periwinkles in the study areas. T – tests showed no significant difference in concentration between tissues and shells of the organism with high correlations (P < 0.05, r =0.9947 for Pb and P > 0.05, r = 0.9611 for THC). The relationships between the concentrations of Pb and THC in thetissues and shells were observed to follow linear and polynomial regression equations. The levels of Pb and THC were higher along the main river than the creeks as a result of dilution and flushing effects of current and volume of water. The levels of lead and total hydrocarbons in the periwinkles were attributed to emissions from automobiles using leaded gasoline for both land and sea transportation in addition to effluents, oil spills and surface coatings from moving and abandoned engine boats as well as industrial and domestic wastes containing metal parts andhydrocarbons. @JASEM

Metal Pollution Assessment of Surface Sediments Along a New Gas Pipeline in the Niger Delta (Nigeria)

Chromium, nickel, copper, zinc and cadmium were determined in sediments of the Niger Delta (Nigeria) in order to discriminate between natural metal sources and anthropogenic ones. Surface sediments were collected at seven sites along a new gas pipeline near Port Harcourt, between the New Calabar River and the Bonny River towards Bonny town. Chemical characterisation is obtained by hydrofluoric-nitric acid digestion procedure, providing the 'total' ('residual') metal contents. Information about the anthropogenic metal fraction was obtained by cold diluted hydrochloric acid extraction procedure. This 'labile' acid soluble fraction of metals, perhaps due to relatively recent inputs in the sediments, constitutes the fraction more likely to be available to marine organisms, and furnishes a first evaluation of the possible toxicity of sediments of this sensitive ecosystem. Zinc appears to be the most available of all the heavy metals: its 'labile' fraction attains 40-50% of the 'total' zinc in sediment. Sites near Port Harcourt city are the most contaminated. All the examined metals are one order of magnitude below the respective values proposed as a limit for toxicity and are comparable with those observed by other authors in similar Niger Delta areas. Some anomalous data found near Port Harcourt city suggest that zinc and cadmium are the metals that require further monitoring. Their anthropogenic source could be derived from urban and industrial sewage.

Impact of atmospheric dispersion of filled LNG cloud from NLNG’s operation

Recently, the demand for natural gas, both as a fuel and as a petrochemical feedstock, has been on the increase. Long distances between producing and consuming nations necessitate marine transportation. For economic reasons, this type of transportation is done with natural gas in liquefied state. NLNG (Nigeria Liquefied Natural Gas Ltd), situated in the western coast of Bonny Island in the Niger Delta area of Nigeria, is one of the industries engaged in this activity, with Bonny River as the take off point.

Studies of water waves in the Bonny River estuary in Nigeria

Studies of water waves in the Bonny River estuary in Nigeria

Probabilistic prediction of capsize applied to small high-speed craft

The prediction of capsize of small high-speed craft is highly complex. In this paper, risk analysis is applied to predict the probability of capsize of two types of high-speed craft due to dangerous wave events in the estuary of the Bonny River in the Niger Delta region of Nigeria. Fibreglass reinforced plastic (FRP) hull craft, widely used for transportation, were considered for the prediction. The probability of the craft encountering a dangerous wave situation at a random position at sea and the probability of capsize were calculated using published wave statistics and computer-based analytical models. Results obtained compared favourably with similar analyses carried out by previous investigators for other regions. Various rational and practical ways of reducing the probability of capsize to an acceptable level are presented. From the prediction it was established that human error was a predominant factor in the capsize of vessels.

Study of food habits of Goby, Porogobius schlegelii (Gunther, 1861) from Elechi creek, off Bonny River, Niger Delta, Nigeria

The study examines the food habits of goby, Porogobius schelgelii from the artisanal fisheries of the Bonny River in the Niger Delta. The results show that detritus, diatoms and blue-green algae are the primary food items followed by sand granules, macrophytes and nematodes as secondary food items. Protozoa. Fish eggs and parts were observed as incidental food items. The Shannon-Weaver Relative Index (J) showed that Porogobius schelgelii are omnivores with no preference for any food items. Also, Shorygin Index (X) indicates that there is a positive intra specific feeding relationship among the various size groups leading to competition for food items. JOURNAL OF AQUATIC SCIENCES Volume 16, Number 2, October 2001, pp. 79-82 KEY WORDS: Food habits, Goby, Elechi Creek, Bonny River, Niger Delta

Effects of amendments on biodegradation of crude petroleum by sediment bacteria from Bonny River Estuary

The biodegradation of Bonny light crude petroleum by bacteria in batch culture was enhanced by the addition to culture media, of 0.2 mg of urea and soya bean lecithin per 100 ml of crude oil, sediment and water mixture. Biodegradation was found to be purely an aerobic process. There was a direct relationship between hydrocarbon content and proportion (%) of total heterotrophic count that was capable of growing on crude petroleum as sole carbon and energy source.

Mercury in the bivalve Anadara ( Senilia) senilis from Ghana and Nigeria

Samples of the bivalve Anadara ( Senilia) senilis collected from a closed lagoon (Sakumo) and two open lagoons in Ghana (Benya and Ningo; n=550), and the Bonny river estuary in Nigeria ( n=620), were analyzed for their total and organic mercury content. Total mercury concentration showed significant spatial differences, with median values of 0.1 μg/g dry wt. in the closed lagoon, 0.2 in the estuary and 0.3 in the open lagoons. Concentration tended to be higher during the dry season in the lagoons, but lower in the estuary. The median relative organic concentration varied between 20 and 60% methyl Hg, depending on location and season. Age effects were detected in the lagoons, total Hg concentration decreasing with length.

The Anthropology of Oil: The Impact of the Oil Industry on a Fishing Community in the Niger Delta

Introduction THE AIM OF THIS ARTICLE IS TO EXAMINE, WITH SOME PARTICULARITY, THE IMPACT of oil upon the lives of people in a small fishing community in the Niger Delta. (1) It is hoped that this data will contribute to the scarce literature available on the Niger Delta and help shed light on the various ways in which oil has affected the institutions of at least one ethnic group. Although it is a detailed descriptive study of one community, the basic problems and tensions discernible in the case study apply to much of the Niger Delta. Ethnographic Background My focus is on the village of Oloma, a rural fishing community on the Island of Bonny in the Eastern Niger Delta. Ethnically, the village's population consists almost entirely of the Ibani-Ijo. The population of Bonny Island is centered in Bonny Town with a number of satellite villages, of which Oloma is one, and several fishing ports dispersed throughout the meandering creeks and waterways. The island is situated within the tidal mangrove swamps of the Eastern Niger Delta. It is bounded by other Ijaw communities, such as those of the Elem Kalabari to the west, the Okrikans to the north, and the Andoni, Opobo, and Ogoni to the east. Bonny is located approximately 50 kilometers southeast of the industrial and commercial center of Port Harcourt. Tributaries of the Bonny River dissect the flat surface of the island, creating swamps and creeks that are bordered by mangrove trees. Much of the land is uninhabitable; fresh water resources are scarce. Historical Overview Traditionally, the Ibani were fisherfolk dependent on the creeks, waterways, and swamps of the Niger Delta for their livelihood. Fish were found in abundance, and salt was evaporated from the sea water trapped in the roots of the mangrove tree. The Ibani traded their fish and salt to the Ibo hinterland in exchange for agricultural produce. This interzonal dependency created the initial trade routes between the Ijo fisherfolk and the hinterland agriculturists. This internal trade network was well established before European contact and provided the mercantile infrastructure on which the success of Bonny's European trade was founded. Bonny's coastal location certainly contributed to her involvement in the burgeoning trade (2) that followed the advent of European adventurers in Bonny as early as the 15th century. Bonny had a pivotal role as the fulcrum of a two-way trade between the Ibo hinterland and the Ibani, on the one hand, and the Ibani and the European traders on the other. Food, livestock, and, most importantly, slaves that came from the hinterland markets were brought to Bonny to be traded. The growing European demand for slaves assured the role of Bonny traders as middlemen in the West African-European trade. This lasted until the 19th century. In the 19th century, the slave trade was abolished and during this period Bonny's merchants turned their attention from slaves to palm oil. The palm oil trade particularly flourished because this new commodity was easily traded along the old channels involving the same personnel. Fortuitously, palm oil became at the same time an important export item because of the Industrial Revolution in Europe. Palm oil was in great demand as a lubricant for machinery as well as for making soap and candles. Bonny prospered during the palm oil trade. Such was its success that the Bonny and Kalabari areas became know as the Oil Rivers. However, in the 20th century, the prosperity of Bonny began to decline. (3) The major factor was the discovery of coal in commercially viable quantities further inland. A new mainland port was built by the British colonial administration, to exploit better the new coal fields. In 1913, a new industrial city, Port Harcourt, located 50 kilometers up Bonny River was opened. Bonny's pivotal trading role was bypassed. Business gradually moved away from Bonny and Bonny only saw ships passing their way up river. …

The fish assemblage of the lower Bonny river, Niger Delta, Nigeria

SummaryThe fish assemblage of the lower Bonny river of the Niger delta with its adjoining creeks was studied. Local fishing gear was used in the collection of samples, which yielded 25 families made up of 57 species. Of these 25 families, some were residents of the main river (Cynoglossus senegalensis, Arius heudoloti, Pentane‐mus quinquarius and Trichurus lepturus) whilst others were creek residents (e.g. Tilapia guineensis, Sarotherodon melanotheron, Citharichthys stamfii and Eleotris vittata). Higher catches were made in the dry season than in the wet season for most of the gear types employed in both the creek and the main river channel. A comparison between the creek and the main channel fish (using Sorenson's index; 0–34) suggests that the creek assemblage is separate from that of the main river channel.RésuméOn a étudie la population piscicole du bas de la rivière Bonny, dans le delta du Niger et dans les criques voisines. On a utilisé le matériel de pêche local pour récolter des échantillons. Ceux‐ci ont réuni 57 espèces appartenant a 25 families. Sur ces 25 families, on a observé que certaines étaient résidentes de la rivière principale (Cynoglossus senegalensis, Arius heudoloti, Pentanemus quinquarius et Trichurus lepturus) alors que les autres sont des résidents de la critique (e.a Tilapia guinensis, Sarotherodon melanotheron, Citharichthys stamfii et Eleotris vittata).Les prises effectuées en saison séche etaient plus importantes qu'en saison des pluies pour la plupart des types d'équipement utilisés, que ce soit dans les criques ou dans le lit principal de la rivière. La comparaison des poissons de la crique avec ceux du lit principal (en utilisant l'index de Sorensen: 0,34) laisse entendre que la population piscicole de la crique est isolée de celle du lit principal de la rivière.