https://journals.unza.zm/index.php/JONAS/issue/feed 2024-06-27T09:35:38+00:00 Levy Siaminwe jonas@unza.zm Open Journal Systems <br>Journal of Natural and Applied Sciences JONAS is a refereed journal open to journal article publication in the fields of engineering, mines, physics, chemistry and biological Sciences as well as allied natural and applied sciences. It is quarterly Journal.<br> https://journals.unza.zm/index.php/JONAS/article/view/1222 2024-06-27T09:35:21+00:00 Levy Siaminwe lsiaminwe@unza.zm

The University of Zambia (UNZA) Journal of Natural and Applied Sciences (JONAS) has reached an editorial-board transition point in 2024, following the expiry of tenure of the current Editorial Board. This JONAS Vol. 6 Issue No. 2 is my last effort as Editor-in-Chief, having assumed office 10 years ago, in 2014. In this editorial I present my personal reflections on managing an academic journal from inception.

2024-06-27T09:24:46+00:00 ##submission.copyrightStatement## https://journals.unza.zm/index.php/JONAS/article/view/1216 2024-06-27T09:35:22+00:00 Rosa Siamachoka siamachokarosa@gmail.com

Climate change is a global challenge brought about by accelerated anthropogenic activities, leading to an increase in the presence of greenhouses gases in the atmosphere. Its impacts are profound in climate sensitive sectors such as smallholder agriculture. Zambia’s smallholder farmers are dependent on rain fed agriculture, and are thus vulnerable to climate change and climate variability. Climate variability, manifested through extreme events such as droughts, floods and abnormal temperatures work synergistically with other factors to affect crop productivity. This study was aimed at examining the determinants of smallholder farmers’ crop productivity amidst variability in seasonal rainfall received in Chongwe, Zambia . Five study sites (villages) in were purposively sampled, namely, Mudenda, Mutakama, Mulwila, Kalilika and Kangalangala. A total of 35 respondents and three key informants were interviewed during this study. The respondents were all smallholder farmers while the key informants were representatives from the Zambia Meteorological Department, Chongwe District Agriculture Office and a Traditional Leader. The trend analysis revealed that rainfall in Chongwe had decreased at an annual rate of 9.60mm between 2000 and 2021. Even though the reduction is not statistically significant (p = 0.181) the downward trend in rainfall should move smallholder farmers to devise adaptation measures to combat the decreased annual rainfall. Further, maize yields had decreased at an annual rate of 0.012 ton/ha between 2010 and 2019 which was not statistically significant (p=0.812). An assessment of social factors that could influence maize productivity revealed household size (r = 0.754; p = 0.012) and farming experience (r = 0.344; p = 0.043) as significant factors that affected maize productivity among the sampled households.. The study concludes that the smallholder farmers studied have experiencing decreased rainfall trends and maize productivity which increases their vulnerability to climate variability and climate change. The study recommends that agricultural development interventions should focus on enhancing the resilience of smallholder farmers in Chongwe through climate change awareness, household income diversification and public social capital mechanisms.

2024-06-27T09:28:34+00:00 ##submission.copyrightStatement## https://journals.unza.zm/index.php/JONAS/article/view/872 2024-06-27T09:35:26+00:00 Prisca Nachalwe Prinanji@rocketmail.com

Mining as an extractive industry has both positive and negative impacts. The positive impacts are economic growth and job creation whereas the negative impacts pose risks to the general environment and human health.  On this premise this study was carried out in order: To i) identify risks posed by mining operations to the environment and human health in Kankoyo and Nkana West, and ii) determine the extent to which the risk management strategies used by mining operators adequately address environmental and health risks in the study areas. The findings showed that the risks from mining in Nkana West residential area were minimal reduced whereas Kankoyo Township was still being impacted by serious pollution from Mopani Copper Mines operations. A questionnaire survey and a number of published articles revealed that Kankoyo and Nkana West are characterised by pollution of air, water and land with Kankoyo being the most affected by air and land pollution. The prominent health problem was respiratory tract infections resulting from smelting activities. Tests carried out on water samples collected from Uchi and Mwekera Streams in Kitwe indicated that Uchi had above limit concentrations of cobalt, manganese and iron which were attributed to effluent discharged from the Nkana mines. With regard to institutional arrangements, it was revealed that they were not adequate and this was evidenced by the relevant authorities’ lack of vital monitoring equipment and human resource for ensuring that mining companies were in compliance with the environmental regulations.

2024-06-27T09:29:39+00:00 ##submission.copyrightStatement## https://journals.unza.zm/index.php/JONAS/article/view/774 2024-06-27T09:35:29+00:00 James Nyirenda nyirendaj@unza.zm Onesmus Munyati omunyati@unza.zm

We report a quick, non-standard informative test method for assessing quality of fabrics intended for making facemasks. Highly efficient N95 facemasks masks are costly in Zambia (about US$ 1.20) hence need for cheap alternative facemask materials. Various materials were tested for filtration efficiency, breathability and effect of washing and ironing on these parameters. Filtration efficiency and breathability for monolayer-unwashed showed from highest to lowest; Java (98.00±1.40%,16754.7Pa/cm2), Telela (12.20±1.0%, 18.9 Pa/cm2); monolayer-washed; Cotton(200) pillow-case (87.1±0.1%,217Pa/cm2),Telela (16.5±0.1%,75.5Pa/cm2). Bilayer-unwashed; Java (99.7±0.1,25669.8Pa/cm2), Telela (59.5±3.5,47.2Pa/cm2), bilayer-washed and ironed; Java (99.7±0.1%,11603.8Pa/cm2), Telela (61.0±1.0%,113.2 Pa/cm2). The plain-inner with outer-honeycomb combination, was; grey (59.2±1.0%,150.9Pa/cm2) , black (52.8±0.8%,245.3Pa/cm2 ), yellow-khaki (99.3±0.3%, 490.6Pa/cm2 ) and stiffener (46.1±0.1%,18.9Pa/cm2). Results show that fabrics available are suitable for fabricating masks. Filtration efficiency increased while breathability remained within appreciable values compared with the reference. Washing and ironing had no significant effect on monolayers. Significance (p=0.0006) was shown when monolayer and bilayer fabrics were compared.

2024-06-27T09:30:47+00:00 ##submission.copyrightStatement## https://journals.unza.zm/index.php/JONAS/article/view/590 2024-06-27T09:35:33+00:00 Sakwiba Musiwa smusiwa@yahoo.com Osbert N Sikazwe osikazwe@yahoo.com Akalemwa Fredrick Kamona fredkamona@gmail.com

The area of north eastern Zambia between, Chama and Lundazi towns, is underlain by biotite gneisses of the Mesoproterozic Irumide Fold Belt dominated by biotite gneisses of the Kampemba group, of the Irumide Fold Belt. A complex of a mafic dyke swarm that appears to occupy a NE trending fracture zone, occurs mainly between the two towns. The dykes have the same trend with the fracture zone. Individual dykes vary in size from about 100s of metres long by a few 10s of metres wide, to about 4 km long and about 100 metres wide. This study examined the petrogenesis of the mafic dyke swarm through the application of petrography, whole rock geochemistry as well as isotope geochemistry. Fifteen fresh dyke swarm samples were sent to Actlabs in Canada for whole rock geochemical analysis. Three of the fifteen samples were analysed for Rb-Sr and Sm-Nd isotope geochemistry, as well as age determinations by K-Ar age dating method. The results received on age determination (geochronology) gave the ages, 1522 ± 90 Ma, 1067 ± 55 Ma and 608 ± 35 Ma. Sm and Nd grades ranged from 1.99 – 3.112 ppm and 6.666 – 9.88 ppm respectively. eNd were calculated by the laboratory at -5.23, -8.23 and -9.73. 87Sr/86Sr returned values of 0.710886, 0.714503 and 0.719612. From the petrographic study of the thin sections and photomicrographs, the studied dyke rocks were classified as gabbroic. They were composed mainly of plagioclase, clinopyroxene, hornblende with subordinate olivine, quartz, sericite, epidote and opaque phase minerals. The dyke rocks occur mainly in course and medium grained varieties as only two of the twelve samples examined, were fine grained. The several diagrams which were generated from whole rock geochemical data and applied in the evaluation of petrogenetic processes revealed that the dyke swarm was emplaced in a back arc continental subduction environment. The geochemical data further revealed that fractional crystallisation affected the magma of both types of rocks identified in the study, tholeiitics and calc-alkalics. Since no two samples came from the same dyke, it was deduced that all the mafic dykes in the Study area experienced various levels of fractional crystallisation of possibly olivine, clinopyroxenes, plagioclase feldspars and hornblende. These were the main minerals which were identified in petrographic studies of the same samples. Both types of dykes show enrichment of the source magma by addition.

2024-06-27T09:31:49+00:00 ##submission.copyrightStatement##