River Benue Research Articles

Livestock Reservoir Hosts: An Obscured Threat to Control of Human Schistosomiasis in Nigeria

Schistosomiasis is one of the leading neglected tropical diseases in sub-Saharan Africa. Recorded case numbers of this chronic and debilitating helminth disease indicate Nigeria to be the most endemic country within this region. National control efforts have focused intensively on restricting human contact with freshwater sources of intermediate host snails. However, limited attention has been paid to the role of livestock as reservoir hosts and the prevalence of transmission of schistosomes to humans via farmed animals. The West African nations of Mali, Senegal, and the neighbouring Niger, Benin, and Cameroon have all reported the hybridization of the closely related species of Schistosoma haematobium, which infects humans, and S. bovis, which infects cattle. As these countries share the Niger and Benue rivers, with their tributaries, there is a distinct possibility of aquatic snails infected with hybrid schistosomes migrating to become established in the Nigerian river system. Here, we report on the current state of research in Nigeria that aims to elucidate key aspects of zoonotic schistosomiasis epidemiology. Factors promoting the hybridization of Schistosoma species are highlighted, and how available control measures can be optimized to address the emergence of schistosome hybrids is discussed.

Assessment of Zooplankton and Physico-chemical Parameters of Upper River Benue, Adamawa State, Nigeria

Between January and June, 2022 some physico-chemical and biological conditions of Upper River Benue were assessed at five selected sites on monthly basis between 6:00 – 10:00a.m. A total of 9.849 ×104 organisms/L was recorded for zooplankton abundance. Rotifera was observed to have a total abundance of 39.9%, followed by Cladocera contributed a total of 33.45%, while the least was Decapoda gave 1.37%. The higher number of taxa (25) was recorded at site V. The abundance of individuals was highest at site IV. Twenty-seven species (27) species of zooplankton were identified during the study period ranging from elven Rotifera, nine Cladocera, five Copepoda, one Ostracoda and one Decapoda. The order of dominance of the zooplankton of Upper River Benue is Rotifera>Cladocera>Copepoda>Ostracoda>Decapoda with Brachionus caudate, Bosmina longirostis and daphnia being the most dominant (6.94%) of the total zooplankton of Upper River Benue. The physico-chemical parameters results revealed that temperature, pH, electrical conductivity, transparency, dissolved oxygen, free CO2, alkalinity were within recommended acceptable limit except ammonia, phosphorus and nitrogen were higher than recommended acceptable limit. However, no significant difference was found between the seasons in terms physico-chemical paraneters and zooplankton distribution (P>0.05). The study showed the reservoir to be eutrophic with moderate water quality, high ecological and pass chemical status, with diverse assemblages of zooplankton. It was recommended that there should be continuous monitoring of the biological and physico-chemical status of the river to ascertain the long-term impact of anthropogenic inputs to take remedial measures so as to ensure the health of aquatic life.

English

Tracking the changes in the river basin system and identifying areas susceptible to flood disasters is an inclusive step in flood hazard control and management. This research analyzed the spatial variability of rainfall and physiographical attributes of the main tributaries of River Benue in Taraba with the aim of identifying areas susceptible to flooding on the basins. The spatial data subjected to WLC approach for reclassification were annual rainfall, digital elevation model, basin slope, land use, soil types, drainage density, and catchment area. The clincher to flooding in the state favors land use. The composite map of flood vulnerability revealed that vulnerable areas occupied 48.6% while highly vulnerable occupied 0.9% of the entire study area of 44,359.2 km2. In terms of the area extent, the highly vulnerable region covers 410.6 km2; the vulnerable area covers 21,576.6 km2, and the areas that are not vulnerable cover 64.9 km2. The towns that are at risk of a high vulnerability to flooding within the study area are Karim Lamido, Gassol, Ibi, Lau, Donga, Wukari, parts of Takum, Ardo Kola, Kurmi, Bali, and Jalingo. It was recommended among others that as the region’s status is vulnerable to climate change and that this has a strong association with land use and land cover change, development along the floodplain should be discontinued.   Key words: Flood vulnerability; land use change; river catchment area; rank-sum method; river Lamurde, Taraba and Donga.

Aspects of the growth and reproductive characteristics of <i>Labeo coubie</i> (Ruppell 1832) in Upper Benue River, Nigeria

Labio coubie is an ecologically and economically important fish of River Benue, thus the length-weight relationship, condition factor and fecundity of the fish were investigated in order to provide information essential for its sustainable management. Fish specimens were collected monthly from sampling stations at Jimeta, Yola, Adamawa State between September, 2017 and February, 2019. A total of 849 specimens were collected and their standard length, body weight and fecundity measured. Regression analysis of the length-weight relationship produced positive allometric growth coefficient, the values of regression coefficient (b) in males, females and combined sexes were 4.02, 3.52 and 3.34, respectively. Condition factor obtained ranged from 2.35-3.38 (mean=2.54±0.22), 2.36-2.78 (mean=2.52±0.11) and 2.36-3.00 (mean=2.53±0.14) for males, females and combined sexes, respectively. Fish condition factor was generally not significantly different (p˃0.05) between seasons. The fecundity of L. coubie ranged between 33,331eggs and 596,250 eggs (mean 78,017±165,667eggs). The mean values of condition factor showed that L. coubie was in a good state of wellbeing in the habitat during the period of study. These results confirm the suitability of upper River Benue for survival of Labeo coubie. There is however need for a systematic closed fishing regime to be employed in order to make way for sustainable growth of L. coubie fisheries in the river.

Corrupt Government Practices, Regulatory Oversignt, Igorance and Negligence, the Key Factors Affecting Sustainable Urban and Rural Devlopments in Nigeria: Heance, Floodings

Human experiences of the urban spaces have been reshaped by events and how the public domain is framed have produced nagging quests for solutions. These are added to the hitherto baffling situations of how the sustainability of urban and rural spaces have often been affected and on many occasions preculded by the decaying urban fabrics, unplanned physical developments and poor space administration. The 2022 flooding in Nigeria, that partly resulted from corrupt government practices and regulatory oversight have destroyed more lives and properties in the country yet, not enough efforts have been put in place to curb the natural catastrophe. The encrochment and destruction of the natural environment without proper and adequate mitigation practices and infrastructural reinforcement of the areas attributed to the problems however, the major factor could be the neighbouring Cameroon’s Lagdo Dam, opened to ease the water pressure on its side of the border along the Benue River without persuasive measures in Nigeria to serve as a buffer. Nigeria still has not completed the Dasin Hausa dam, started decades ago that would have been two-and-a-half times the capacity of the Lagdo dam in Cameroon, and would generate 300MW of electricity and irrigate about 150,000 hectares of farmland across three states and that needs to be rectified.

Food and Feeding Habits of Eutropuis Niloticus in Lower River Benue, Makurdi

This study investigated the food and feeding habits of Eutropius niloticus in the lower River Benue to determine the diet composition in the stomach of E. niloticus and determine the dietary overlap. Fifty samples of the species were collected, and their stomach contents were analyzed by frequency of occurrence, numerical and volumetric methods. The IRI (Index of Relative Importance) was used to determine the stomach contents. The results showed that E. niloticus is an omnivorous fish that feeds on fish (IRI = 13.98%), crustaceans (IRI = 21.04, eggs/larvae (IRI = 14.78%), worms (IRI = 9.95%), insects (IRI = 11.52%), green algae (IRI = 0.87%), plant tissues (IRI = 1.15%), and plant seeds (IRI = 2.75%).

Evaluation of physico-chemical parameters and heavy metal concentrations in muscles of Synodontis courteti and Mormyrus macrophthalmus from lower River Benue, Ibi, Taraba, Nigeria

Heavy metals concentrations in muscles of Synodontis courteti and Mormyrus macrophthalmus from lower River Benue, Ibi, Taraba state was examined. The heavy metals concentration in the species under consideration was studied with atomic absorption spectrophotometer (AAS). Bulk Model 210VGP scientific equipment. Results obtained confirmed the occurrence and levels of the following heavy metals (lead (Pb), cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), zinc (Zn) in muscles of the two commercially important species investigated. Recorded values of heavy metals in muscles of S. courteti and M. macrophthalmus overtime showed the metal concentrations ranking profile Pb >Cd >Cr >Cu >Zn > Mn were higher for S. courteti than M. macrophthalmus. Cadmium (Cd) and Chromium (Cr) showed variation (p>0.05) in concentrations for both species November and December, exception of October. Heavy metal concentration of M. macrophthalmus showed less variation with location (p, Mn>, Pb>, Cu>, Cd>, Cr. Between location upstream and downstream. However all values recorded for the metals were within safe limit The levels of Pb, Cr, Cd, Cu, Mn, Zn in the Muscles of the species studied were below WHO/FAO and FEPA recommended limits in fish and fishery products. Lead (Pb) values was low throughout the study period in both species except for the month of October which was higher downstream. Though Pb, Cd and Cr Values was within the permissible limits recommended by FAO and FEPA for fish/fisheries products. This study also reported on some physico-chemical parameter of importance (temperature, pH, D.O., Electrical conductivity (EC) and TDS,) and they were found to be within acceptable levels for sustainable fish survival and growth. The need for continuous monitoring and conservation of the fish and fisheries resources of lower River Benue waters and the heavy metals content therein cannot be overemphasize.

Land Use Land Cover Dynamics of Upper Benue River Basin, Nigeria

This study examined land use land cover (LULC) dynamics in Upper Benue River Basin, Nigeria. The study makes use of primary and secondary data. Landsat Imageries for the years 1981, 2001 and 2021 were used in the study. Supervised approach with maximum likelihood classifier was adopted for the classification and generation of LULC maps. Markov Cellular Automata model was used to predict the status of LULC of the catchment for year 2070. The findings of the study reveal remarkable changes in the land use land cover of the Upper Benue River Basin. The land cover has witnessed downward trend in the percentage area covered by vegetation and bare surface resulting in 15.4% and 2.6% losses respectively. The result of the findings reveals that the built-up area and rock outcrop has shown significant gains of 15.2% and 2.9% of the study area respectively. Water body has been stable with 0% change, though, it witnessed a marginal decline in 2001. The land use land cover change observed in the Upper Benue River Basin was as a result of anthropogenic factors characterized by deforestation, expansion of agricultural lands, overgrazing among others. Based on the findings, the study recommended controlled grazing activity, deforestation and indiscriminate fuelwood exploitation and improved agronomic practices in the basin.

British Colonial Marine Transport Services in the Niger-Benue Confluence Area of Nigeria, 1914–1918

This paper focuses on the British marine transport services in the Niger-Benue confluence area of Nigeria during the First World War. It posits that the flow of the Benue River through the Northern Nigeria/Cameroon border was a major way through which the British war resources were conveyed from the Niger-Benue confluence area to the battlefronts against the German Cameroon. The paper claims that the British authorities used lies as strategy by painting the Germans as land grabbers to get the locals’ commitment and support during the war at the expense of marine transport services. It reveals that the colonial authorities’ deployment of marine personnel and facilities in the prosecution of the war almost paralysed marine transport services in the area and beyond. The Marine Department (MD), the colonial authority that provided marine services on the waterways, lost 40 British marine officers, 4000 Nigerian personnel and had 12 of its vessels destroyed in the war. The deployment, as discovered, made the MD to neglect its primary responsibilities of maintaining and providing marine transport services in the Niger-Benue confluence area in particular, and Nigeria in general. The development affected nearly every other part of colonial Nigeria economically as the utilisation of Niger-Benue Rivers (which formed the major navigable trading routes) for the war created shortages of imports and scarcity of shipping resources. A wide range of sources from primary to textual analyses in extant literature are used to explain how marine transport in the confluence area fared during the First World War.

Evaluation of the effects of abattoir effluent on the physicochemical and bacteriological quality of River Benue, Nigeria.

This study investigated the impact of continual discharge of untreated abattoir effluents on the water quality of River Benue. Three major abattoirs (Wurukum, Wadata and Northbank) in Makurdi, Nigeria, and their polluting strength in river upstream and downstream were measured and compared. Two water quality parameters: physicochemical and bacteriological were investigated. Water quality index (WQI) was computed for all sampling sites. Results revealed that some of the physiochemical parameters were above recommended limits, especially in downstream river, in particular, the turbidity (24.0-55.5mg/l), TSS (62.6-92.0mg/l), DO (8.0mg/l), and total hardness (160-240mg/l). All sampling sites indicated an increased bacterial population while Salmonella spp. and Escherichia coli were the predominant bacteria among the ten genera identified in water upstream and downstream. Faecal coliforms increased from upstream to downstream in two sampling sites (Wurukum and Wadata). Strong positive correlations were observed between upstream and downstream samples for pH, EC, turbidity, TSS, DO, COD, SO42-, TC, and Shigella spp. WQI revealed that all sampling locations were heavily polluted and unsuitable for drinking purposes (WQI > 300) based on both the physicochemical and bacterial parameters. The sampling sites, however, showed excellent water quality based only on physicochemical properties especially upstream at both Wurukum and Northbank sampling sites (WQI < 50). It was suggested that anthropogenic activities around the river may be responsible for the high concentration of some physiochemical parameters and bacterial loads observed in the river downstream. Moreover, it was concluded that microbial loads should be fully considered in WQI computation in terms of water quality. Our results are useful for water resource and waste management in terms of practices and policy guidance, especially for developing countries.

Prevalence of fish Parasites IN Bagrus bayad and Protopterus annectens from Upper River Benue in Mutum Biu, Taraba State, Nigeria

The prevalence of fish parasites in Bagrus bayad and Protopterus annectens from Upper River Benue in Mutum Biu, Taraba State, Nigeria was carried out using standard parasitological method. The objectives of this study were to investigate the parasite species spectrum, prevalence of each parasites species, overall prevalence, prevalence of parasite infection in relation to the size and sexes of Bagrus bayad and Protopterus annectens and the infection induced by parasites on/in their body parts, with the view of providing relevant information that can be used in combating the rate of economic losses that could be experienced as a result of parasitic infestations. 4 parasite taxa comprising of Twelve (12) parasite species (Trichodina spp., Henneguya spp. Cryptobia iubilans, Diphillobothrium latum, Hymenolepis nanna and Bothriocephalus aengypticus, Capillaria philipinensis, Caenorhabditis briggsae, Camallanus spp., Eustrongylides spp., Contracaecum spp. and Clinostomum spp. were recovered from the samples of fish species used during the study period. Twelve (12) of the parasite species were recovered from Bagrus bayad while seven (7) were recovered from Protopterus annectens. Among the body parts of Bagrus bayad, while intestine had the highest percentage parasite load (56.37%), highest percentage parasite load (46.22%) in Protopterus annectens was recorded for stomach (46.22%). Out of the 400 fish samples comprising of 200 each of Bagrus bayad and Protopterus annectens, 234 (58.50%) comprising of 99 (49.50%) and 135 (67.50%) samples each of Bagrus bayad and Protopterus annectens were infested with 369 and 119 parasites, respectively. However, there was no significant difference in the prevalence of infection and parasite load between the fish species, respectively (P&gt;0.05). Generally, larger sized samples of Bagrus bayad and Protopterus annectens had higher percentage of infection compared to the smaller sized of both samples although, the prevalence of infection in relation to sizes of both fish species was not statistically significant (P&gt;0.05). Female Bagrus bayad and Protopterus annectens had higher prevalence of infection (21.61%) and (16.63%) than the males (6.37%) and (6.24%), respectively. There was no significant difference in the prevalence of infection in relation to the sexes of both fish species (P&gt;0.05). Epidermal necrosis of the caudal fin and skin, thickened intestinal epithelium at the site of parasite attachment, hyperplasia of the intestinal villi and lamina propria, hyperplasia of infected gills at the secondary lamellae, ulceration of the stomach, abdominal distention, eroded and flattened intestinal folds and lymphocytic infiltration of intestinal mucosa and edema of the lamina propria of the intestine were observed with the infected samples of B. bayad. The infected samples of P. annectens exhibited epidermal necrosis of the skin.

Effects of Glyphosate and Butachlor Herbicides Concentrations on Resident Culturable Bacterial Populations from Surface Water Sources in Makurdi: A Microcosm Study

The effect of different concentrations of herbicides on bacterial isolates from various surface water sources was undertaken. The research was aimed at the isolation, identification and characterization of bacteria from selected surface water sources, in order to ascertain the effects of varying concentrations of herbicides on resident bacterial populations. Samples were obtained from five different surface water sources and sediments in Makurdi, using sterilized plastic containers. The herbicides used were Butachlor and Glyphosphate ammonium salt with Rid-over’s trade name (500, 250, 125, 62.5 and 31.5 mg). Both herbicides were spiked in the volume of water samples to reflect the recommendation of the manufacturer). The bacteriological analysis of the samples prior to spiking with the herbicides indicated that, Afuko stream had the highest total heterotrophic bacteria (THB) count of 4.55x107cfu/mL; River Benue 3.45x107cfu / mL; Akighir stream 3.0x107cfu / mL; whereas Mu river and Jamu stream had the lowest total heterotrophic bacteria count of 2.36x107cfu / mL and 2.31x107cfu/mL respectively. The isolates from the water sources in the order of highest percentage occurrences included; Escherichia coli 24(21.7%); Bacillus sp 22(21.2%); Salmonella sp 20(17.6%); Pseudomonas sp 17(15.0%); Proteus sp 16(14.1%) and Staphylococcus aureus 14 (12.3%) before spiking with the herbicides. The number of bacteria colonies increased as the days increased after spiking at different concentrations of the herbicides though colony counts were higher at lower concentrations than higher concentrations. The bacteria isolates have shown resistance to herbicides, which implies biogenic elements for their physiological processes.

FARMING ADAPTATION STRATEGIES TO CLIMATE CHANGE IN RURAL COMMUNITIES ALONG RIVER BENUE IN ADAMAWA STATE NIGERIA

This research work investigates the adaptation strategies to climate change by rural communities along river Benue in Adamawa State Nigeria. A multistage sampling was also employed, in the first stage three communities were randomly selected from each of the selected LGAs and the second stage involves the allocation of four hundred and sixty-three interview schedules to respondents. The data obtained were analysed using descriptive and inferential statistics such as percentages, cross tabulations and Chi square. The result of the study showed that farmers in the study area are aware of climate change uncertainties. The study also reveals that farmers practiced various adaptation strategies. The study recommends that improved crop varieties that are able to withstand severe droughts, tolerate higher temperatures and mature early should be developed

Egg development stages and fecundity of Atya gabonensis (Giebel, 1875) (Crustacea: Atyidae) from three different locations in Nigeria

Comparative studies of fecundity and stages of egg development of Atya gabonensis in River Benue at Makurdi, River Niger, Jebba and the confluence of the two rivers at Ganaja was done from January 2016 to December 2017. A total of 300 berried females were collected with the aid of fishermen and transported in ice box to the laboratory for further studies. Species identification was done using keys of Powell (1982). The sexes were determined using morphological features such as appendix masculina, reproductive chamber and numb. Morphological measurements were done according to Adite et al. (2013). Body weight was taken with a top loading electronic Metler balance. Fecundity was estimated by gravimetric method. Egg development stages were determined using external features of the eggs. The number of eggs varied from 550-36,673 in Jebba, 300-24,532 in Ganja and 4,300-8,600 in Makudi. Positive correlation was observed between fecundity and morphometric parameters in all the locations. All the ovigerous females in Makurdi, 14% in Ganaja and 17% in Jebba were in stage 1. Ganaja and Jebba had 39 and 35% respectively in stage 2. Stage 3 was 26 and 12% from Ganaja and Jebba respectively. Stage 4 had 10% from Ganaja and 17% from Jebba while stage 5 had 11% from Ganaja and 19% from Jebba. It was concluded that A. gabonensis is fecund and could make an excellent candidate for culture.

Parasitic incidence in cultured and wild Nile tilapia (Oreochromis niloticus) in Makurdi, Benue State, Nigeria

Parasitic incidence in cultured and wild Nile tilapia (Oreochromis niloticus) in Makurdi, Benue State, Nigeria was investigated by standard parasitological techniques using 305 samples comprising 146 and 159 Oreochromis niloticus randomly purchased from the cultured (Ponds) and wild (Lower River Benue) environments, respectively. Nine (9) parasite species belonging to two (2) species each of crustacean (Argulus spp. and Ergasilus spp.), protozoa (Trichodina spp. and Ichyophthyirius multifilis), cestode (Ligula intestinalis and Bothriocephalus spp.) and a species of monogenea (Cichlidogyrus spp.), digenea (Clinostomum spp.) and nematode (Camallanus spp.) were recovered from the examined fish. All the parasites were present in both environments with the exception of I. multifilis that was recovered from the wild O. niloticus. Out of the 146 and 159 samples of cultured and wild O. niloticus, 81 and 62 samples each were infested with 128 and 93 ectoparasites and endoparasites, respectively. The overall prevalence (55.48%), mean intensity (1.58) and abundance (0.88) were higher for cultured O. niloticus compared to the overall prevalence (38.99%), mean intensity (1.50) and abundance (0.58) recorded for the wild O. niloticus. The prevalence and intensity of infection in most of the parasite species were higher (9.59 and 1.50, 7.53 and 1.36, 2.74 and 1.25, 2.05 and 3.33, 5.48 and 1.88, 2.05 and 2.33, respectively from the cultured environment; 6.92 and 1.45, 6.29 and 1.30, 1.26 and 0.50, 0.63 and 2.00, 2.52 and 1.25, 1.26 and 4.00, 3.14 and 1.60, 1.26 and 2.50, respectively from the wild) in females than the males (7.53 and 1.18, 5.48 and 1.13, 1.37 and 1.50, 1.37 and 3.00, 3.42 and 1.60, 0.68 and 2.00, respectively from the cultured environment; 6.29 and 1.20, 4.40 and 1.29, 0.63 and 3.00, 0.00 and 0.00, 0.00 and 0.00, 0.63 and 3.00, 2.52 and 1.25, 0.00 and 0.00, respectively from the wild). Ectoparasites of cultured and wild O. niloticus were more in the gills (114) compared to the skin (25) while endoparasites of cultured and wild samples of O. niloticus were more in the intestine (48) compared to the stomach (40). Parasite prevalence was higher in the bigger fish samples compared to the smaller ones.

Influence of fishing gears used by fisherfolks on fish yield in River Benue, Nigeria

This study was carried out to ascertain the influence of fishing gear used by fisherfolks on the yield of fish in River Benue, Nigeria. The study was conducted in three fishing villages that are also landing sites. They are within Adamawa State axis with the Benue River passing through them. The selected villages are Boranji (Site 1), Damare (Site 2) and Hayin gada (Site 3). The study was conducted bi-monthly for three months from the month of July to September 2021. In the conduct of this study, both primary and secondary methods of data collection were used. A total of One Hundredand Forty (140) respondents were sampled with structured interview and questionnaire. The study showed that the fishing gears employed and operated in the study sites are used to capture different species of fish. Most prominent of the gearsu is the gill net and Malian trap. The study also revealed that Sixteen (16) fish species from seven (7) families were caught by the six artisanal fishing gears in all the sites. The study revealed the obvious neglect of the artisanal fisherfolks with regards to provision of infrastructural facilities despite the enormous contribution they give to the domestic fish output.

Appraisal of Socio-economic, Infrastructural and Environmental Impacts of Flood in Makurdi Local Government Ares of Benue State, Nigeria

Among the common natural hazards experienced in the world today, flood is said to be the most devastating in terms of the area covered and frequency of occurrence. Floods cause serious damage to lives and properties, disrupt economic activities, and, in turn, threaten the sustainable development of human settlements. In Nigeria, flooding has become a recurring phenomenon, sometimes with devastating effects. This study was aimed at assessing the socio-economic, infrastructural, and environmental impacts of floods in Makurdi Local Government Area (LGA). A non-probability sampling technique involving the use of a well-structured questionnaire was adopted in obtaining the required information. Purposive random sampling was used to select four hundred (400) flood victims from the nine (9) local wards bordering the Benue River. Analysis was done using Microsoft Excel and the findings were presented in tables and charts using percentages. The result showed that floods have a huge impact on the community, with greater damage 44% recorded on socio-economic activities (farming, marketing, and administration), followed by a 32% impact on infrastructural facilities (roads, hospitals, and schools), and a relatively lower impact 24% recorded on environmental variables (water, land, and vegetation). An Analysis of Variance (ANOVA) test conducted on these revealed that there is a significant variation in the impact created by floods on the study variables. Flood mitigation and preparedness plans were found to be the leading challenges to long-term flood disaster management in the area. The paper calls for collaborative efforts from residents, flood disaster management agencies, or stakeholders to reduce the impact and improve decisions towards ameliorating the menace of floods in the area. The evidence in this paper seeks to promote actions toward combating flooding and improving flood disaster management in Nigeria.

Assessing River Benue flow data for flood mitigation and management in Adamawa catchment, Nigeria

Information on the historical patterns, seasonal variation of river flows, and flood frequency necessary for flood mitigation in the Adamawa catchment are limited. In this study, river flow and water stage time series for stations within River Benue reaches were analysed and peak flows were computed using the Weibull formula. The stage time series was decomposed to extract cycles and trends using the classical multiplicative (CM) model. Subsequently, spectral analysis was performed for periodogram/spectrum comparison of actual and fitted values from the decomposition modelling. The findings show that the peak flows for 10-year, 25-year, 50-year, and 100-year designed flood for the stations exceed the danger level at Jimeta and Numan. Moreover, water heights of 6.3 m (∼3400 m3/s for Jimeta) and 9.3 m (∼4800 m3/s for Numan) were observed. The implication when compared to the designed flood discharge for different return periods is that there will be increased flooding in the catchment. CM modelling accuracy showed that the root mean square error was 0.8114 cm (Jimeta), 0.0160 cm (Ngurore West), and 0.0004 cm (Dong) with R2 not below 98% in each case. A deep-climax pattern that indicates seasonality was observed, and the seasonal variation is believed to be the result of changing weather.

First DNA barcode library for the ichthyofauna of the Jos Plateau (Nigeria) with comments on potential undescribed fish species.

Located in the central region of northern Nigeria, the Jos Plateau covers approximately 9,400 km² with an average altitude of 1,280 m and constitutes a unique terrestrial ecoregion known as the Jos Plateau forest-grassland mosaic. The biota of the Jos Plateau include endemic elements, but very limited information is available on its ichthyofauna. This is despite the fact that the ancient plateau contributes to several large rivers spanning multiple major drainage systems including the Niger and Benue Rivers, and Lake Chad. This study provides the first species list for the fishes of the Jos Plateau based mainly on 175 DNA barcoded museum voucher specimens representing 20 species, and another three species without a DNA barcode. In total, 23 species from eight families and 17 genera were collected from the Jos Plateau including five putatively new species, four in the family Cyprinidae and one in the Clariidae. With ten species, the Cyprinidae is the most diverse fish family on the Jos Plateau, followed by Clariidae and Cichlidae, each with three species. The study also provides data on species distribution and habitat parameters including information on water chemistry that strongly suggests that selected water bodies are heavily impacted by anthropogenic activities. Urgent management steps are required to preserve the unique and diverse fish communities of the Jos Plateau and their habitats.

Hydrochemistry of nutrients in groundwater under farmland in the Benue River Basin, North-Cameroon

In this study, we investigated the distribution and the principal sources of macronutrients (N, P, K, S) in groundwater in agro-pastorally dominated North Cameroon. Graphical methods and multivariate statistics were used to understand the impact of land use and regional geology on nutrient concentrations (K+, NO3−, SO42−, PO43−). Groundwater was acidic (median pH 6.8) and more mineralized (EC range = 35–2500 µS/cm, median = 376 µS/cm) than surface water (EC range = 50–222 µS/cm, median = 81 µS/cm). The median concentration of nutrients was (in mg/L) in the order NO3− (41.3) > SO42− (7.7) > K+ (5.2) > PO43− (0.1) in groundwater and rather K+ (3.3) > NO3− (0.3) > SO42− (0.2) > PO43− (0.2) in surface water. Using hierarchical cluster analysis and Schoeller diagram, we identified three distinct water quality groups. Group I, which contained cluster 1 and 2 were generally less mineralized and characterised as Na + K − HCO3 water type found in the urban area such as Garoua and Lagdo. Group II, containing cluster 3 was much higher mineralized and characterised as the Na + K − HCO3 water type with elevated nitrate. The occurrence of these groups is linked to the outcrops of cretaceous terrestrial sediments of the Garoua basin. Group III, which contained cluster 4 were heavily mineralized and characterised as the Ca + Mg − NO3 water type. The occurrence was controlled by the outcrop of the crystalline Proterozoic basement. The nitrate median (41 mg/L) found in groundwater demonstrates the influence exerted by anthropogenic activities. Management strategies are required for the whole study area to limit further deterioration of groundwater resources in the wake of the planned expansion of agricultural productivity in the North Region of Cameroon.