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Author(s):
Anyanwu Daniel Chimeriri.
Page No : 1-12
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Evaluation of Dump Site Soil on the Growth Parameters and Yield of Okra (Abelmoschus Esculentus (L) Monech).
Abstract
The use of urban waste as soil amendment is increasingly gaining attention in developing countries due to its potential to improve soil fertility and reduce waste accumulation. This study evaluated the effect of dumpsite soil manure on the growth and yield of okra (Abelmoschus esculentus) in Owerri, Southeastern Nigeria. A field experiment was conducted during the 2020 cropping season using a Randomized Complete Block Design (RCBD) with six treatments (0, 5, 10, 15, 20, and 25 t/ha of dumpsite manure), replicated three times. Data were collected on percentage emergence, plant height, stem girth, number of leaves, leaf area, leaf area index, fruit number, fruit weight, and fruit yield. Results revealed that dumpsite soil manure contained higher organic matter, nitrogen, phosphorus, and potassium compared to the topsoil, but also elevated levels of heavy metals such as Pb, Cd, and Zn. Application of manure significantly (P<0.05) enhanced growth parameters and yield attributes relative to the control. The highest manure rate (25 t/ha) consistently recorded superior performance in plant height (49.30 cm at 8 WAP), stem girth (3.30 cm at 10 WAP), leaf number (9.67 at 6 WAP), leaf area index (7.38 at 10 WAP), and fruit yield (75.67 kg/ha). Although heavy metals were present in the manure, their concentrations in okra leaves and seeds remained below FAO/WHO permissible limits, and no visible toxicity symptoms were observed. The findings demonstrate that dumpsite manure is a valuable low-cost organic fertilizer that improves soil fertility, growth, and productivity of okra. However, the elevated heavy metal content raises concerns about long-term food safety and soil health. The study recommends manure application at 20–25 t/ha for optimal yield, alongside regular monitoring and co-composting with safer organic residues to mitigate heavy metal risks.
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Author(s):
Eid I. Brima, Parvez I. Haris.
Page No : 13-30
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Analysis of Essential and Toxic Elements in Tap and Bottled Water from the UK and its Comparison with Literature Data for Drinking Water from African Countries: Implications for Human Health.
Abstract
This study compares the presence of essential and toxic elements in UK and African waters. Drinking water samples (n=93) were collected from Leicester, UK [45 bottled drinking water (BDW) and 48 tap drinking water (TDW)]. Concentrations of 26 elements were determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Notably, cadmium (Cd) and lead (Pb) were detected only in TDW samples, with detection percentages of 25% and 60.4%, respectively. In contrast, very low concentrations of arsenic (As) and mercury (Hg) were detected in 82.2% and 100% of BDW samples and in 88.9% and 95.6% of TDW samples, respectively. All detected element concentrations were within World Health Organization safety limits. The hazard quotient (HQ) and Incremental Lifetime Cancer Risk (ILCR) values for toxic elements were below the permissible limits, suggesting no significant long-term health risks. In contrast, recent literature from some African countries has revealed high concentrations of toxic elements, such as Pb and As, with HQ and ILCR exceeding guidelines. Consumption of water can be higher in African countries, which have warmer climates, and this will further increase their exposure to toxic elements compared to the UK. There is an urgent need to lower toxic elements in African drinking waters through improvements to the water treatment and distribution systems.
| 3 |
Author(s):
Okelola O. E., Alufohia G. O., Babalola D. O., Balogun O. L., Ayantoyinbo A. A..
Page No : 31-48
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Value Addition and Profitability in Fish Marketing: Evidence from Southwest, Nigeria.
Abstract
This study investigates the role of value addition in enhancing profitability among fish marketers in Southwest Nigeria. Using data from 769 marketers in Lagos, Ogun, and Ondo States, the research evaluates the types of value-added products, returns on investment (ROI), and the factors influencing product choice. A descriptive survey design, and ROI analysis were applied. The research analyzes pooled data on nine fish products (Fresh, Smoked Fish, Fried Fish, Fish Fillets, Dried Fish, Fish Powdering, Frozen Fish, Fish Barbecue, and Fish Kilichi) and ten fish types (Catfish, Tilapia, Shiny Nose, Panla, Asa Fish, Croaker, Barracuda, Abo, Okodo, and Obokun). Data were gathered from fish marketers and processors, targeting nine fish products. Results indicate that fresh fish dominates the market (57.26%, 769 instances), with Catfish leading (31.20%), followed by Asa Fish (13.74%) and Shiny Nose (11.14%). Value-added products, notably Smoked Fish (27.78%) and Fried Fish (21.28%), are prevalent, reflecting significant adoption of processing techniques to enhance shelf life and profitability. Niche products like Fish Powdering (1.30%) and Fish Kilichi (0.65%) are limited to specific fish types, indicating specialized market niches. Findings reveal that smoked fish is the most common and profitable value-added product. Female marketers dominate the sector, and their product choices are influenced by experience, credit access, and training. The study also highlights regional variations, with Ogun State leading in dried and smoked products due to its proximity to aquaculture hubs, while Lagos excels in frozen and filleted fish owing to better infrastructure and market access. Overall, value addition not only boosts profitability with profits per kg reaching
₦4,600 for dried Asa fish but also contributes to food security by increasing fish supply and nutritional value, aligning with Nigeria's evolving blue economy.
The study recommends investment in infrastructure, financial support, and capacity building to improve market outcomes. These results provide empirical insights to strengthen Nigeria's fishery value chain in line with SDG targets.
