West African Journal of Applied Ecology

Adsorption of Heavy Metals from Landfill Leachate using Fish Scale Biochar

2024-12-19T13:42:29+00:00

Heavy metal contamination is a serious environmental issue that can affect both humans and animals' health in many ways. The study was to explore the potential of fish scale biochar as an adsorbent for the removal of toxic metals from landfill leachate. The acquired fish scales were properly cleaned with deionised water and allowed to air dry for three days. After that, they were heated to a temperature of 10°C per minute in an inert atmosphere and allowed to sit for 60 minute in a muffle furnace. The initial and final concentrations of heavy metals of landfill leachate was measured using Atomic Absorption Spectrophotometer after treatment with fish scale’s biochar at minimum of 0.50 g to a maximum of 2.50 g. The adsorption efficiency of chromium with fish scale biochar ranged 99.71% to 99.84%. The efficiency of cadmium adsorption with fish scale biochar produced about 99.80% to 99.98%. The percentage efficiency of nickel in the landfill leachate ranged from 99.30% to 99.55%. The maximum adsorption capacity (Q_e) for chromium, cadmium, and nickel were 9.52 x 10^-6, -2.80 x 10^-5, and 1.82 x 10^-5, respectively with coefficient of determination (R²) of 0.7758, 0.1765 and 0.6831, respectively. Fish scale’s biochar possesses efficient potentials with its high surface area and porous nature. Further research should be conducted using different time to assess the adsorption efficiency of pollutants.

Prospects of Enhancing Cattle-Dung Manure’s Effectiveness by Partial Substitution with Poultry Droppings-Compost Mix for Slash-and-Burn Managed Tropical Soils

2024-12-19T15:10:06+00:00

Use of animal manure-based soil amendments may offset the detrimental effects of slash-and-burn practice by smallholder farmers. Cattle dung is relatively more abundant but mineralizes slower and hence less effective than poultry droppings which can be made even more effective by co-application with the more readily mineralized compost. This study evaluated the potential of a 50% substitution of the slow-release cattle dung with a mix of equal volumes of poultry droppings and fruit-waste compost (CD:PD&FWC) for restoring the fertility of slash-and-burnt tropical soils on the growth of mung bean as a test crop. Screenhouse soil fertility trials were carried out utilising slash-and-burn managed sandy-loam Ultisols from a Nigerian rainforest, with soil properties showing slight improvement over the unburnt soil. Treatments were CD:PD&FWC (10 t ha^–1), cattle dung (10 t ha^–1), NPK-15:15:15 (125 kg ha^–1), and unamended control. At the termination of crop growth after 10 weeks, CD:PD&FWC showed the highest soil pH (5.86), soil organic matter (33.70 g kg^-1), total nitrogen (2.00 g kg^–1), available phosphorus (25.15 mg kg^–1), and cation exchange indices. Soil content of exchangeable acidity showed a reverse trend with lowest values from CD:PD&FWC (0.36 cmol kg–1) and highest from NPK- 5:15:15/control (1.10 cmol kg^–1). Cattle dung gave longer plant roots than CD:PD&FWC, but the two produced higher root dry matter (2.74-3.27 g pot^–1) than NPK-15:15:15/control (0.70 g pot^–1). The CD:PD&FWC gave taller 10-week-old plants (30.69 cm), more root nodules (415) and higher shoot dry matter (37.80 g po^t–1) than cattle dung; NPK-15:15:15/control gave the lowest (14.77 cm, 26-37 and 5.95 g pot^–1, respectively). The CD:PD&FWC and, to lesser extents, cattle dung improved soil fertility and mung bean growth. Organic amendment CD:PD&FWC is, therefore, preferred to sole cattle-dung manure for improving the productivity of slash-and-burnt acid coarse-textured soils of the humid tropics.

Bath Towel Bacterial contamination and Hygiene practices among Tertiary Students

2024-12-19T15:49:07+00:00

Bath towels have the ability to support bacterial growth under inappropriate washing and drying conditions and pose health risk to humans. This study investigated bacterial contamination of bath towels used by tertiary students and the washing and drying practices relative to their use. Coliforms (23, 46%) including Escherichia coli (18, 36%) were isolated by culture methods using swab samples from standardized area (0.96cm²) of 50 bath towels owned by tertiary students. Male students had a higher rate of coliform contamination on towels (15, 60%) than female students (8, 32%) [χ²(1) = 3.87, p = 0.049]. E. coli contamination was also more common in males (13, 52%) than females (5, 20%) [χ²(1) = 5.44, p = 0.019]. Mean rank colony counts differed for coliforms in male (29.68) vs. female (21.32) towels (U = 417, p = 0.027) and for E. coli in male (30.16) vs. female (20.84) towels (U = 429, p = 0.008). Biochemical tests identified bacteria in seven genera, four coliform species: Escherichia coli, Serratia marcescens, Citrobacter freundii, Enterobacter species and three non-coliform species: Vibrio cholerae, Salmonella typhi, and Alcaligenes species. Seven male students (28%) and 16 female students (72%) reported washing their towels within two weeks of use. More males (16, 64%) than females (8, 32%) washed towels one to two months after use. Bacterial contamination of students’ towels raises concern about the risk of exposure to potentially harmful bacteria and calls for appropriate towel hygiene practices by students.

Organic Farming: A Practice for Conserving Arthropod Diversity and Soil Health in an Agroecosystem

2024-12-19T16:31:46+00:00

The sustainability of any agroecosystem depends on agricultural practices, arthropod diversity and soil health. This study assessed the diversity of arthropods and some soil parameters (soil organic matter (SOM), pH and Temperature (oC)) of three organic (ORGF) and conventional (CONF) farmlands at University of Nigeria, Nsukka. Each farm measured 10,000 m², 100 m apart was divided into four quadrants with pitfall traps (7.20 × 4.80 cm). Arthropods were collected weekly for three months and were preserved in a vial containing 70 % ethanol before identification. Soil samples were collected with auger at 10 cm depth, analyzed ex-situ for SOM and pH, in-situ for Temperature using standard protocols. A total of 172 arthropods belonging to six orders, 10 families, 19 genera and 15 species were observed with ORGF having higher number (n =113; 65.69%) than CONF (n = 59; 37.31%). Camponotus perrisii nigeriensis was the most dominant species (n =37; RA=21.51) while Anochetus siphneus, Gymnopleurus coerulescens and Gyna costalis were the least (n=1; RA=0.58). Hymenoptera were higher in ORGF (n=58) than CONF (n=9). Shannon-Wienner diversity index revealed that ORGF had more species diversity (H=2.21) than CONF (H=1.48) which varied significantly (p ≤ 0.05). Descriptive statistics showed that SOM was higher in ORGF (1.89 ± 0.34) than CONF (1.26 ± 0.45), pH higher in ORGF (5.44 ± 0.06) than CONF (2.34± 0.28) while Temperature was higher in CONF (27.23± 0.05) than in ORFG (24.09 ± 0.25). Diptera and Hymenoptera showed negative correlation with soil parameters while the rest showed positive. Organic farming had minimal effects on arthropods and soil parameters therefore it should be encouraged.

Reduced Indoor Air Pollution but Increased Cooking Time and Fuelwood Consumption of Improved Local Cookstoves in Asuogyaman, Ghana: Implications for Appropriate Stove Design

2024-12-19T16:44:04+00:00

The intense wood extraction and use in traditional stone fires (TSF) for cooking in the Asuogyaman district in Ghana are associated with deforestation and indoor air pollution (IAP). Therefore, efforts have been made by the volta river authority (VRA) to provide improved local cookstoves christened "climate-smart stoves" to inhabitants of this region. However, these improved cookstoves (ICS) were designed to hold two cooking pots concurrently, contrary to the typical traditional cooking practice of using one pot in the Asuogyaman District. Although this may impact the performance of ICS compared to TSF in terms of reducing cooking time, fuel use and IAP, to date, limited information exists about this impact. This field study evaluated the performance of ICS relative to TSF using the controlled cooking test (CCT) protocol. The CCT involved 10 ICS and 10 TSF households. The test results show that the indoor CO and PM_2.5 concentrations were 5.470 ± 4.668, and 0.451 ± 0.328 mg/m³, respectively, for ICS and 13.485 ± 10.925, and 0.867 ± 0.839 mg/m³ for TSF. Compared to TSF, ICS increased cooking time and fuel use by 78% and 46%, respectively. The findings reveal that aside from efficiency, it is essential to prioritize traditional cooking practices and users' needs when designing improved cookstoves. In conclusion, we assert that ICS contributes significantly to reducing respiratory health issues thus making it ideal for cooking among rural folks. To reduce cooking time and fuel use for ICS however, we recommend that the stove be redesigned in terms of the material used for its construction and the number of pot- holes.

Impact of Climate Change on the Distribution of Vachellia tortilis subsp. raddiana (Savi) Kyal. and Boatwr. In Eastern Niger

2024-12-19T16:53:30+00:00

The multipurpose species Vachellia tortilis (umbrella thorn) is a woody plant whose parts are extensively used for food, feed, traditional pharmacopoeia, energy, and handicrafts. The species also provides multiple ecological benefits. This study aims at assessing the impact of climate change on the geographical distribution of V. tortilis in Eastern Niger, by analyzing the climatic factors influencing its current distribution and predicting its future distribution areas under different climate scenarios. Species occurrence data were collected and combined with bioclimatic data derived from the WorldClim database and vegetation data. Two climate models were used for future projections (RCP 4.5 and RCP 8.5). Results from the Jackknife test showed that five variables contribute significantly to the models. V. tortilis has a wide distribution, being present in all agroecological zones, with a high concentration in the Sahelian zone. Future climate projections for 2055 indicate an increase in the current vegetational range of species of 19.8% to over 30%. However, the potential distribution of the species is not compromised by the 2055 climate projections or local disturbance factors. The species will remain highly suitable for the study area, continuing to provide all the ecosystem services it offers.

Leachate characterization and pollution index as a tool for landfill management: The case of Nsumia Waste Facility in Accra, Ghana

2024-12-19T17:03:34+00:00

Landfills are most countries' primary structures by which solid wastes are disposed of. However, most landfills are not properly engineered and therefore tend to pose a threat to health and the environment, especially through the leachate they produce. The leachates are difficult to treat and, in most cases, are either not adequately treated or not treated at all before release into the environment. This study was conducted to identify the dominant pollutants, assess leachate pollution potential, and identify a suitable treatment approach to leachate from an active municipal solid waste landfill site in Accra, Ghana. Physico-chemical and biological results from leachate analyses indicated the landfill site was in its methanogenic phase. The overall leachate pollution index (LPI) of 12.55, LPI organic (LPI_org = 19.08), and LPI inorganic (LPI_in = 16.00) were much higher than the standard values for treated leachates before disposal into the environment. Individual pollution ratings show that TDS, Hg, COD, and BOD were the major pollutants influencing the leachate pollution indices. Based on the fact that the organics and the inorganics are the major influencers of leachate toxicity, the tandem operation of co-treatment with wastewater and membrane bioreactor treatment of leachate is recommended.