Advanced Journal of Environmental Science and Technology

Advanced Journal of Environmental Science and Technology ISSN 2756-3251, Vol. 15 (10), pp. 001-010, October, 2024. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research Paper

Characterization of Ambient Air Pollution in Freetown, Sierra Leone: A Study of Toxic Air Pollutant Levels

Eldred Tunde Taylor1, 2 and Satoshi Nakai1*

1Graduate School of Environment and Information Sciences, Yokohama National University, Japan.
2Institute of Environmental Management and Quality Control, Njala University, Sierra Leone.

Accepted 22 May, 2024

The ambient air quality in Freetown, Sierra Leone was investigated for the first time for toxic air pollutants. We investigated the levels of polycyclic aromatic hydrocarbons (PAHs), suspended particulate matter (SPM) and carbon monoxide (CO) and considered the implication of air quality and health risks. Particulate samples for PM2.5 and PM2.5 to10 fractions were collected from four sites, and analyzed by HPLC/FLD. SPM and CO were monitored by realtime monitors. The annual average concentrations of total PAHs for PM2.5 and PM2.5 to10 fractions for the various sites were found to be 37.18 and 6.24 ng/m3. The average concentration of SPM was 216.3 count per min (cpm) and the 8-h average concentration of CO was 10 ppm. Higher concentrations of PM2.5 and PM2.5 to 10 PAHs were found in dry season compared with wet season. The annual carcinogenic potential of PAHs was high in PM2.5 fraction while the levels of SPM and CO were high enough to raise concern of health risks. The ambient air quality in Freetown was judged to be poor and in view of human exposure, large portion of urban residents are exposed to high levels of toxic air pollutants which is recognized to be a public health risk.

Key words: Air pollution, polycyclic aromatic hydrocarbons, suspended particulate matter, carbon monoxide,
African countries.
 

Advanced Journal of Environmental Science and Technology ISSN 2756-3251, Vol. 15 (10), pp. 001-008, October, 2024. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research Paper

Heavy Metal Adsorption from Aqueous Solutions Using Cassava Starch Hydrogel: An Eco-Friendly Solution

L. O. Ekebafe1*, D. E. Ogbeifun2 and F. E. Okieimen2

1Department of Polymer Technology, Auchi Polytechnic, P.M.B. 13, Auchi, Nigeria.
2Centre for Biomaterials Research, University of Benin, P.M.B.1154, Benin City, Nigeria.

Accepted 22 May, 2024

Graft copolymers of cassava starch and acrylonitrile were synthesized in aqueous solution using ceric ammonium ion as the initiator. Saponification of grafted copolymer was done by reaction with sodium hydroxide and precipitated with methanol. Grafting was confirmed by Fourier transform infrared spectroscopy (FTIR). The grafted copolymer and the hydrolyzed graft copolymer (hydrogel) were used as sorbent for the uptake of heavy metals from the aqueous media. The sorption capacity was evaluated by measuring the extent of sorption of nickel, copper, and leads metals ions, under equilibrium conditions. Using the sorption isotherm models, the Freundlich model was found suitable because of good fitness and equilibrium data yielded the following ultimate capacity values for the sorbent of the grafted copolymer: 54 mgPb/g, 64.5 mgCu/g and 71.1 mgNi/g and for the hydrogel: 72 mgPb/g, 76.6 mgCu/g and 86.5 mgNi/g. Hydrolysis increases the sorption affinity of grafted copolymer toward metal ions. Acid stripping with 2% HCl resulted in 99.6% metal recovery for the hydrogel and 52.2% for the grafted copolymer. This shows the ability of the product to be reused, upon drying between treatments.

Key words: Acrylonitrile, cassava starch, grafted copolymer, heavy metals, hydrogel, sorption.
 

Advanced Journal of Environmental Science and Technology ISSN 2756-3251, Vol. 15 (9), pp. 001-008, September, 2024. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research Paper

Adapting to Climate Variability: Leveraging Browse Trees for Enhanced Livestock Production in Southern Zambia's Agro-Pastoral Communities

O. C. Chibinga1*, N. R. K. Musimba2, M. M. Nyangito2, J. Simbaya1, M. T. Daura1

1Department of Animal Sciences, School of Agricultural Sciences, University of Zambia, P. O. Box 32379, Lusaka,
Zambia.
2Department of Land Resource Management and Agricultural Technology, University of Nairobi, P. O. box 29053,
Kangemi, Nairobi. Kenya.

Accepted 24 April, 2024

Agro-pastoralists whose sources of livelihood depend on rain-fed agriculture are very vulnerable to ecological disturbance due to increasing climate variability. They are unable to adequately feed their animals in times of extreme weather conditions of floods and droughts thereby causing a disruption in their major source of livelihood. This study analyzed the feeding strategies employed by agro-pastoralists in Southern Zambia and important browse species used in extreme weather conditions, in order to improve their utilization for improved livestock production. The major feeding strategies during droughts include browse utilization, dambo grazing, grazing along streams and supplementary feeding. While during floods, upland grazing and browse grazing were the main strategies. However, most of the agro-pastoralists do not practice pasture management and fodder conservation for their animals. Of the 21 tree browse species identified by the agro-pastoralists, 18 species were found to be important during droughts and 8 during floods. Most of the agro-pastoralists neither knew how to plant these browse species nor how to manage them for better and sustainable use in feeding their animals. Therefore, the agro-pastoralists in the study area need to take up management and feed conservation measures for their animals. Deliberate effort should be made to teach the agro-pastoralists how to plant and manage the important browse species that are suitable in extreme weather conditions. This will enhance productive use of the browse species for improved animal feeding to ensure food security among the pastoralists.

Key words: Extreme weather conditions, adaption, browse species, Agro-pastoralists.
 

Advanced Journal of Environmental Science and Technology ISSN 2756-3251, Vol. 15 (9), pp. 001-011, September, 2024. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research Paper

Diversity and Distribution of Phytoplankton in Ndop Wetland, Cameroon

Fonge B. A.1*, Tening A.S.2, Egbe E. A.1, Yinda G. S.3 , Fongod A. N1 and Achu R. M.3

1Department of Plant and Animal Sciences, University of Buea, P. O. Box 63, Buea, Cameroon.
2Department of Chemistry, University of Buea, P. O. Box 63, Buea, Cameroon.
3Department of Environment Sciences, University of Buea, P. O. Box 63, Buea, Cameroon.

Accepted 14 May, 2024

Phytoplankton is very sensitive to nutrient changes. Very little work has been carried out on the effect of these changes on the phytoplankton community in the Ndop wetland. Four paddy-field sites were studied to evaluate the effect of some abiotic factors on their occurrence and abundance of phytoplankton. Water samples were collected from the paddy-fields sites following age gradient 34, 32, and 5 years old fields. Potassium, sodium, nitrate-nitrogen, phosphate-phosphorus, conductivity and pH were the factors that contributed to phytoplankton diversity and density. There was a positive significant correlation between pH and potassium (r = 0.99, P ≤ 0.01), and pH and sodium (r = 0.977, P ≤ 0.05). A negative correlation (r = -0.992, P ≤ 0.01) was observed between pH and evenness. Eight divisions of phytoplankton were recorded: Chlorophyta (26.42%), Bacillariophyta (20.76%), Pyrrhophyta (20.76%), Cyanophyta (15.09%), Chrysophyta (1.87%), Xanthophyta (3.77%), Rhodophyta (1.87%), and Euglenophyta (7.55%). The most abundant species included Microcystis aeruginosa, Anacystis sp., Chlorococcus disperses and Peridinum sp. These may be used as bioindicator of the water quality. Diversity index increased with increase in the age of paddy-fields sites. 43% of the species indicated eutrophic status, 16.9% mesotrophic, and 20.8% oligotrophic. Eutrophic species were more in the older paddy sites while the young paddy sites had more oligotrophic species.

Key words: Phytoplankton, diversity, abundance, pollution, Ndop wetland.

Advanced Journal of Environmental Science and Technology ISSN 2756-3251, Vol. 15 (9), pp. 001-004, September, 2024. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research Paper

Marine Bacteria as a Source of Biosurfactants: Isolation and Characterization

Seema Dhail1* and Nakuleshwar Dut Jasuja2

1Laboratory of Microbiology, Department of Biotechnology, International College for Girls, Rajasthan University,
Jaipur-302004, India.
2Department of Biotechnology and Allied Sciences, Jayoti Vidyapeeth Women’s University, Jaipur- 303007, India.

Accepted 6 June, 2024

Biosurfactant-producing marine bacteria were isolated from oil-spilled seawater collected from harbors and docks in Mumbai, India. Haemolytic activity, emulsification activity toward n-hexadecane, emulsion of mixtures of oils, drop collapsing test as well as oil displacement test were used to determine biosurfactant producing activity of marine bacteria. Among 25 strains, 20 different strains showed biosurfactant activity in which only 6 strains had haemolytic activity and were able to emulsify mixtures of oils (kerosene + petrol + diesel) in Marine Broth 2216 during cultivation. Six strains named MW1, JN1, MS3, JN2, MS1, and MW2 were identified by various identification tests. MW2 (Pseudomonas sp.) Strain showed the highest emulsification activity against n-hexadecane. In addition, MW2 showed the highest activity for oil displacement test (3.14 ± 0.02) and emulsification test (70.5 ± 0.55) towards n-hexadecane.

Key words: Biosurfactant, emulsification, bacteria, haemolytic, extreme conditions, oil.
 

Advanced Journal of Environmental Science and Technology ISSN 2756-3251, Vol. 15 (8), pp. 001-005, August, 2024. Available online at www.internationalscholarsjournals.org © International Scholars Journals

Full Length Research Paper

Sustainable Biogas Enhancement Using Marine Streptomyces clavuligerus-Derived Enzymes: A Novel Eco-Friendly Strategy

T. Stalin1*, B. Sathya Priya1 and K. Selvam2

1Research and Development Centre, Bharathiar University, Coimbatore-641046, Tamil Nadu, India.
2Department of Biotechnology, Dr. N.G.P Arts and Science College, Coimbatore-641014, Tamil Nadu, India.

Accepted 5 June, 2024

The marine actinomycete strain MAC 9 was used for the production of cellulase and xylanase from wheat bran with inducers oats and soy meal as substrate. Out of 30 actinomycetes screened from sediments of Tiruchendhur coastal areas of Tamil Nadu, India only 8 strains showed both cellulase and xylanase activity. The marine actinomycete exhibited highest enzyme activity at alkaline pH 8-9 with temperature ranging from 40-55°C. The enzymes were used in pretreatment of rice and wheat straw waste for biogas production. More biogas production was observed in the agricultural waste with the pretreatment of cellulase, xylanase and the combination of enzymes.

Key words: Biogas, cellulase, energy, marine actinomycete, solid state fermentation, thermophilic, wheat bran, xylanase.