UNAM Open Access Journal University of Namibia
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Efficacy of selected biopesticides against the tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), in Lusaka, Zambia
Full text linkThe aim of this research was to evaluate the efficacy of four commercially available biopesticide for[1]mulations, Azadirachtin indica, Beauveria bassiana, Metarhizium anisopliae and Verticillium lecanii in the management of Tuta Absoluta (Meyrick)(Lepidoptera: Gelechiidae) under laboratory and field conditions. Analysis of variance (ANOVA) using Fisher’s least significant difference test (α = 0.05) showed that the mean percent mortality ranged from 41.3±6.8% to 77.9±14.3%. A. indica caused the highest mortality of 77.9±14.3% while mortality due to B. bassiana, V. lecanii, and M. anisopliae was 48.3 ± 2.8%, 44.8 ± 4.8% and 41.3 ± 6.8%, respectively. The estimated LC50 for A. indica was 30.4 µL±0.4, while LC50 for B. bassiana, M. anisopliae, V. lecanii were 107.1 µL±0.4, 193 µL±0.4 and 118.7 µL ± 0.4, respectively. Biopesticide efficacy on larval mortality from highest to least was A. indica, B. bassiana, V. lecanii and M. anisopliae respectively. Percentage corrected mortality ranged from A. indica (69.8 ± 8.1 to 88.4 ± 41.9%), B. bassiana (32.6 ± 4.0% to 60.5 ± 16.3%), V. lecanii (30.2 ± 1.7% to 55.8 ± 14.6%) and M. anisopliae (32.6 ± 4.0% to 53.5 ± 5.4%) respectively. The selected biopesticides significantly (P < 0.001) reduced T. absoluta egg count compared with the untreated control. Performance ranged from A. indica (2.8 ± 1.1 and 10.7 ± 1.2), B. bassiana (3.0 ± 0.6 and 10.7 ± 1.9), V. lecanii (4.3 ± 1.2 and 11.7 ± 1.4) and M. anisopliae (6.8 ± 1.4 and 13.0 ± 1.6) for egg mortality, respectively. The study showed that selected biopesticides were effec[1]tive and should be used by farmers as an integral component of Integrated Pest management (IPM) in the control of T. absoluta in Zambia. Further research should evaluate the effectiveness of the selected biopesticides in other agroecological zones of Zambi
Learners level of awareness on the values of wildlife(ecosystem services) in Mudumu South Complex, Zambezi Region, Namibia.
Full text linkCurrently, youth are the future generations of the country, their awareness of the values of wildlife is critical in determining if they will follow the footsteps of the current generation in conserving natural resources (wildlife) and cannot be overemphasized. This study was conducted in Wuparo and Balyerwa conservancies, to assess learners’ level of awareness of wildlife-based ecosystem services. Questionnaires were used in data collection and the target population consisted of learners including teachers (control group) resulting in a sample size of 145 respondents who were randomly selected from eight indiscriminately selected schools within the two randomly selected conservancies. The results showed learners knew that wildlife has values (ecosystem services). However, they are highly aware of tangible benefits (provisional services) compared to other ecosystem services. There was a positive correlation (R2 = 0.9995) between level of awareness and level of education. The availability of wildlife-related subjects, location of the school, lack of environmental clubs and ignorance towards wildlife were the major factors reported to influence the awareness of learners. Increased support for education among the youth and improved support for environmental and wildlife clubs can be beneficial to wildlife and environmental conservation
Public Spending as a Predictor of Livestock Total Factor Productivity in Namibia
Full text linkThis paper investigates public spending and its catalytic role towards a productive agricultural sector. This was done empirically by testing how agricultural total factor productivity could be increased. Data used is for the period 1991 to 2021. A Tornqvist-Theil Index was developed. A simultaneous equation became the chosen and implementable analytical tool for this study. While an agricultural total factor productivity index for Namibia did not exist before, the livestock component was generated for the first time in this study to fill this gap. Stunning is the fact that the Malabo declaration in terms of its convergence target of 10% is not yet met. The results show that by increasing productive labour to the livestock subsector by 10%, real gross domestic product will increase by 12%. Likewise, should capital formation and spending towards agriculture be increased to 10%, the growth of the agricultural sector will increase by 8.5%. This would require input-base needs to be expanded for output to increase. The work done by the Namibian Government so far yearn for further efforts to create more jobs, increase food production, and foreign income earning, remains to be addressed. To achieve all these, compliance with the Malabo declaration would be necessary.
Treated wastewater as a resource for sustainable water supply in Windhoek, Namibia: : Overview, drivers and benefits
No full textFor decades, Windhoek, which is situated in arid Namibia, was under chronic water stress due to diminishing water supply and increasing water demand. To enhance sustainable and adequate quantities of potable water for diverse water requirements, the first wastewater recycling plant in Africa was constructed. This paper provides an overview of Windhoek’s water resources and shows how treated wastewater makes an invaluable contribution to promoting the security of supply. The paper concludes that the main drivers for implementing wastewater recycling plants are population growth, urbanisation and industrialisation coupled with poor rainfall, drought and climate change coupled with the paucity of alternative freshwater sources within this central area in Namibia. Windhoek’s experience shows that treated wastewater does play a key role in the water supply system, but it requires adequate upgrading, comprehensive planning, training and ongoing commitment for its continued success
The Role of local communities in resource management: A case of Okongo Community Forest and Conservancy, Namibia
No full textThis paper presents the role of communities in resource management, with particular focus on the Okongo Community Forest and Conservancy. The study is part of the main research work that examined perspectives on community-based management practices, including the conservation area boundaries, but most importantly, the roles and responsibilities of various actors within the conservation area. The study was conducted to understand the state of community-based natural resource management (CBNRM) in the Okongo Community Forestry and Conservancy. It also explored the relationship between government functionaries and the local resource committees that are in existence as critical complementary proponents in the realisation of sustainable natural resource management. The study used a mixed research design, comprising qualitative and quantitative methods, and with this design, data collection methods included interviews and focus group discussions in four communities in the Okongo Community Forest and Conservancy, namely: Omauni East, Omauni West, Oshalandeand Kumininenge. A purposive sampling method was employed to select participants for the study. The study revealed that the management of resources such as water, wildlife, grazing areas and forestry was possible through management committees. Most of the committees were established with the aid of the government. The majority of respondents observed positive relationships between the government and thecommittees; only few did not. Membership on such committees can be attributed to a strong interest in the management of resources, although some members are elected to serve in leadership positions irrespective of their commitment to resource management. Sadly, there are conflicts around the management of resources. However, these conflicts are either resolved strategically through community meetings or are directly dealt with by the committees. Overall, community participation has greatly improved access and the integrity of natural resources by ensuring equal distribution of resources and services within the conservation area
Namibia towards ending poverty, protecting the planet and ensuring prosperity for all
No full textAlthough Namibia has made advancements towards the attainment of its National Vision 2030, a snapshot of the 17 Sustainable Development Goals (SDGs) shows varied results. For instance, while the country has made significant progress towards economicgrowth, attaining an upper-middle-income country (UMIC) status, it still faces high levels of inequality. Moreover, certain groups such as women, youth, people with disabilities, and marginalised communities lag far behind. In addition, the rural-urban divide in terms of access to public and social services such as health, education, water, energy, and sanitation inclusive of quality of services are prominent. This article presents some of Namibia’s accomplishments while highlighting challenges revealed by the dichotomy of its development progress. The article paves the way for in-depth research, particularly on issues of leaving no one behind (LNOB), inequalities, and addressing the last milechallenges in an UMIC context to inform policy-makers with evidence
Marginality and migration:: Children trapped in a cycle of economic, educational and psycho-social marginality in Bulilima and Mangwe Districts of Zimbabwe
Full text linkInternational migration and marginality are among the immense challenges of humankind worldwide. Many studies have focused on the marginality of migrants in destination countries. This study, however, focuses on the marginality of children left behind by parents due to labour migration. The objectives of the study are to determine forms of marginality, and economic, educational and psycho-social experiences of marginalisation of children left behind by migrating parents. It also explores strategies to mitigate the effects of marginality on left-behind children. Theories of marginality and social exclusion make up the theoretical framework for this study. The study design is a qualitative phenomenological inquiry probing on lived experiences and challenges of marginalised migrant children in Bulilima and Mangwe districts of South-West Zimbabwe. The sample comprised a total of 94 participants, 18 class teachers, 40 caregivers and 36 left-behind migrant children. The instruments were in-depth interviews for class teachers and caregivers as well focus group discussions for left-behind migrant children. The results revealed that children left behind experienced different forms of marginalisation ranging from economic, structural, cultural, educational and psycho-social marginalisation. Ecological marginality, migration and poverty intertwine to tap migrant children in a cycle of educational and psychological marginalisation. The study recommends synchronised intervention strategies by government policymakers, non-governmental organisations, educationists and community member engagement to mitigate the effects of marginality among left-behind children
Antimicrobial and anti-biofilm activities of Diospyros lycioides root, leaf and twig extracts against Staphylococcus aureus and Mycobacterium avium
Full text linkThis study utilised the minimum inhibitory concentration (MIC) assay and the microtiter plate assay to investigate the antimicrobial and anti-biofilm activities of D. lycioides crude methanolic extracts against Staphylococcus aureus and Mycobacterium avium. Thin layer chromatography was used to qualitatively screen for the presence of phytochemical compounds in the plant methanol and aqueous extracts. Phytochemical analysis revealed the presence of all tested compounds in the methanol extracts, except for saponin. These included coumarin, triterpenoids, anthraquinone, tannins, alkaloids, steroids and flavonoids. On average steroids, tannins, triterpenoids and anthraquinones were the most abundant phytochemicals in both aqueous and methanol extracts, with the highestamounts observed in the methanol extracts. The minimum inhibitory concentration against M. avium occurred at 75mg/ml, 37.5mg/ml and 18.75mg/ml for the root, leaf and twig methanol extracts, respectively while for S. aureus all methanol extracts showed an MIC of 75mg/ml. The highest biofilm inhibition against S. aureus was due to the methanol extracts of D. lycioides leaves (57.2%) and roots (58.1%). However, the twig methanol extracts (57.8%) inhibited M. avium biofilm formation the most as compared to the leaf (25.6%) and root (35.3%) extracts. The leaf extracts (40.4%) were moderately active in eradicating S. aureus biofilms, whereas for M. aviumthe highest eradication activity was observed with the root extracts (35.6%)
Characterization of the nutritional values of agro-industrial by-products in Namibia as potential supplements of the bush-based feeds: Agro-industrial by-products
No full textThe objective of this study was to characterize the nutritional values of Namibian agro-industrial by-products (AIBPs) as potential supplements for bush-based feeds. Fourteen AIBPs’ samples were collected from Namibian local cereals and oilseed processing companies. Cereal by-products were malt dust fine (MDF), pearl millet bran (PMB), malt dust coarse(MDC), white maize chop (WMC), wheat bran(WB), brewer’s spent grains(BSG), sorghum brew residue (SBR) and sorghum spent grains (SSG), while oilseed byproducts were olive oil cake(OIC), marula oil press (MOP), jojoba oil cake (JOC), !nara oil cake(NAC), manketti oil cake (KOC) and marula oil cake (MOC). Chemical compositions, in vitro gas production, in vitro organic matter digestibility, and metabolizable energy of the AIBPs were determined in a randomized complete block design and the data were statistically analyzed using a Statistical Package for Social Science. Crude protein, ether extract, neutral detergent fiber, and acid detergent fiber ranged from 7.90 (SSG)-21.95 %( BSG), 1.37(MDF)-9.29%(PMB), 22.23(WMC)-73.06%(BSG), 7.22 (PMB) -30.46% (BSG) respectively for cereal by-products and 7.55(OIC)-37.3% (MOP), 8.11(KOC)-53.55%(MOC), 11.40 (MOC)-58.26%(KOC) and 8.21(MOP)-52.26%(MOP) in oil seeds by-products respectively. The in vitro gas production, in vitro organic matter digestibility, and metabolizable energy ranges for cereal and oilseed by-products were 31.50 (BSG)-70.20ml/200mgDM(WMC), 55.55 (BSG)-83.50%DM(WMC), 9.30(BSG)-14.00MJ/Kg(white maize chop), and 3.80 (MOP)-35.30ml/200mgDM(jojoba oil cake), 38.95(MOP)-59.35%(JOC), and 7.45(MOC)-15.95MJ/Kg(MOP), respectively. The AIBPs investigated in this study comprised of minimal fiber contents, adequate crude protein, and metabolizable energy contents above minimum requirements for ruminant animals. However, promotion to maximally utilize these AIBPs in animal diets requires further evaluation
Assessment of physical vulnerability to flooding using Geographic Information System (GIS)-based Multi-Criteria Decision Analysis (MDCA) in Lephalale Local Municipality in Limpopo, South Africa
No full textFloods are one of the most common recurring natural disasters globally. They impact communities by damaging natural resources, disrupting economic activities, destroying property and livelihoods, displacing people and causing loss of lives. In South Africa, predictions are that flood incidences are likely to increase due to climate change, hence placing communities at risk of floods. This study sought to assess and map the physical vulnerability of areas to flooding in the Lephalale Local Municipality using a Geographical Information System (GIS)-based Multiple Criteria Decision Analysis (MCDA) approach. Using various indicators, a composite map was developed showing the different levels of vulnerability to floods in the municipal area. Physical vulnerability to floods was found to be higher in the central regions compared to the rest of the municipal area, because of the high magnitude of the rainfall in the central region, its proximity to rivers, and the presence of impermeable bare soils that increase runoff. The north, west and southern parts of the municipal region showed moderate to low levels of vulnerability due to their slightly higher elevation, longer distances from rivers, and the presence of natural vegetation land cover. The study concluded that physical vulnerability to floods in the area was largely a result of the interaction of various factors, namely: proximity to river channels, precipitation amount, altitude, and soil type. Although the study demonstrated the usefulness of the GIS-based MCDA approach in assessing physical vulnerability to floods, we recommend that future studies also consider integrating social, economic, cultural and institutional indicators to capture the multi-scale and multi-faceted dimensions of flood vulnerability