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Item Influence of enclosure geometries and internal installations on the explosion pressure of hydrogen-air mixtures(University of Namibia, 2025) Uunona, Ndamononghenda N.; Chiguvare, ZivayiThe use of green hydrogen gas as a clean energy carrier solution is gaining global momentum and Namibia is on track to being one of the major producers of green hydrogen. The growing emphasis on green hydrogen has elevated the importance of safety in its value chain. This thesis investigates the influence of enclosure geometries and internal installations on the explosion pressure of hydrogen-air mixtures within flameproof enclosures. The aim of this work is to investigate two critical aspects: the impact that different flameproof enclosure geometries have on the explosion pressure, and the role that internal installations play in exacerbating or mitigating the phenomenon of pressure piling. Experimental tests were conducted in the metrological laboratories of Physikalisch Technische Bundesanstalt, an Institute in the Federal Republic of Germany in compliance with the international standards, such as IEC 60079-1, in order to adhere to the safety guidelines which are vital for preserving structural integrity during hydrogen explosions. These experiments were conducted using specific enclosure geometries – spherical, cylindrical and multi-chambered enclosures. Different orifice sizes and welded internal installations were used to replicate the real-world industrial conditions of pressure piling. The results demonstrated that enclosures with complex geometric design and internal installations were more susceptible to pressure piling effects due to localised pressure compression and uneven pressure distribution. Additionally, this work highlighted the importance of the proper design of the enclosure, emphasizing the need for optimized internal configurations to minimize risks. The findings from these experiments contribute to enhancing and improving the design of flameproof enclosures, potentially informing future regulatory updates, promoting safer practices in hydrogen production plants, and ultimately, bridging the existing knowledge gaps in hydrogen explosion protectionItem Design and performance evaluation of an oil/rock bed heat storage system for solar cooking(University of Namibia, 2025) Naule, Cecilia N.; Chiguvare, ZivayiThis thesis presents the development and performance evaluation of a sensible thermal energy storage system that used sunflower oil and rock pebbles as heat storage mediums. The aim was to assess the system's performance based on charge and discharge rates, energy storage capacity, power output, cooking efficiency, and cost-effectiveness. The main body of the system was created with an old hot water geyser. An Arduino-based data logger was fabricated and was used to monitor and capture temperature changes throughout system operation periods. The data was analyzed with Python programming, from which time-temperature graphs were drawn. The heat retention capacity was obtained by heating the system to about 200 °C and then cooling it, with the time taken to cool being recorded. The system took approximately 30 hours to cool from 194℃ to 60℃. The system generated 0.028 kW of power and stored a total of 0.85 𝑘𝑊ℎ of heat energy. The efficiency testing, which involved boiling five liters of water, yielded an average efficiency of 78.98%. The total cost of constructing the system was: N$ 3,860, with a unit energy cost of N$ 1.26/kJ and a unit power cost of N$ 137.86/W. The cooking test demonstrated that the system could simultaneously cook 300 g of rice in 43 minutes and 300 g of dry beans in about 4 hours using only the stored thermal energy. The study therefore concluded that the developed system was able to deliver a reliable and cost effective solution for domestic use. Nonetheless, constraints including insufficient funding for further development and a limited timescale, impeded comprehensive investigation of the system's capabilities. Future research needs to improve the design of the system as well as explore the possibility of using solar PV panels to heat the TES systemItem Variations in the use of artificial waterholes by mammals at Okaukuejo and moringa in Etosha National Park, Namibia(University of Namibia, 2025) Mthethwa, Nomkhuleko Vangile Helen; Mfune, John K. E.The presence of artificial waterholes can alter local mammal biodiversity. Research on the impact of artificial waterholes on local mammal biodiversity and studies on the nocturnal patterns of water usage are limited in Namibia. In this study, large mammals that visited Okaukuejo and Moringa artificial waterholes in Etosha National Park were studied in the cool dry season in July 2022 to determine and compare their species richness, patterns of waterhole usage, duration of stay, and behaviors displayed at the waterholes. A total of 14 large mammal species were recorded at both waterholes. Species richness was significantly higher at Okaukuejo than at Moringa waterhole, with cape fox (Vulpes chama), blue wildebeest (Connochaetes taurinus), giraffe (Giraffa camelopardalis) and warthog (Phacochoerus africanus) sighted at either Moringa or Okaukuejo waterhole. Zebras (Equus quagga) and springboks (Antidorcas marsupialis) had the highest abundance at both waterholes and visited at all sampling sessions (03h00- 06h00, 07h00 10h00, 12h00-15h00, 17h00-20h00 and 22h00-01h00). This indicates more water dependence than other species and may be influenced by the diet and home ranges of these species. There was a temporal differentiation in the use of the waterholes; mammals mostly visited between 12h00-15h00 and least between 03h00-06h00. Low overlap in waterhole visitation times was observed between predators and potential prey, possibly due to predation risk. The duration of mammal stay was significantly higher at Okaukuejo than at Moringa for elephants (Loxodonta africana), springboks, and spotted hyenas (Crocuta crocuta). Duration of mammal stay was significantly higher between 22h00 01h00 at Okaukuejo, and significantly lower between 03h00-06h00 at Moringa than other sampling sessions. Black rhinos, elephants and giraffes stayed significantly longer at Okaukuejo, while black rhinos and elephants stayed significantly longer at Moringa, compared to other species. Vigilance and aggression were the most frequently observed behaviors among 13 behavior types recorded, possibly driven by the need for water, predation risk and competition for water. Behaviors occurred at a higher frequency at Okaukuejo waterhole due to higher species richness and abundance. This study provides valuable insights on the activity patterns of mammals around artificial waterholes. Repeated and seasonal observations, incorporating water quality tests at waterholes are recommended for year-round assessment of mammal waterhole use and for explaining variations in visitations, species distribution and behaviors of mammals at waterholesItem Vegetative and reproductive biomass allocation responses of herbaceous plant species to induced drought in a semi–arid highland savanna, central, Namibia(University of Namibia, 2024) Nashini, Martha E.; Kwembeya, EzekielNamibia's arid conditions renders its vegetation vulnerable to changes in precipitation, affecting plant growth and biomass allocation. Recurring droughts, intensified by climate change lead to alterations in biomass allocation. Thus resulting in the reduction of medicinal products, livestock fodder, and food sources while disrupting nutrient cycles. This study investigated herbaceous drought responses in biomass allocation and the influence of environmental variables on these patterns, aiming to inform ecosystem management to conserve Namibia's biodiversity. Twenty fixed rainout shelters (4 m x 4 m) were used at Neudamm Agricultural Farm to simulate drought conditions with four treatments (0%, 20%, 40%, and 80% rainfall reduction), each replicated five times. Environmental parameters, including temperature (measured with a mercury thermometer), soil moisture content and chlorophyll content (using a SPAD-502 Plus Chlorophyll meter) were recorded before biomass harvesting. Biomass was collected from 0.5 m x 0.5 m quadrants, with aboveground biomass clipped at ground level and belowground biomass obtained through soil excavation. The Generalized Linear Models indicate that drought treatments are significant predictors of reproductive biomass allocation (χ²(3) = 13.114, p < 0.004), while temperature significantly influences vegetative biomass allocation (χ²(1) = 17.103, p < 0.004). The Friedman test results show a significant difference in chlorophyll content across drought treatments (χ² = 18.456, df = 1, p < 0.001), with Aptosimum lineare and Ocimum americanum exhibiting the highest chlorophyll levels under treatment 60 highlighting the resilience of these species in arid savannas. These findings underscore the significant impact of drought on biomass allocation and the need for targeted interventions to mitigate its effects on plant growth and developmentItem A comparative study on the fish species composition, diversity and catch rates among the fisheries reserves on the Zambezi and Kwando rivers, Zambezi region(University of Namibia, 2025) Namitaa, Tukelo Lavinia; Mfune, John K. E.The Zambezi and Kwando Rivers in northeastern Namibia support vital floodplain fisheries that provide food, income, and seasonal employment for many local communities. However, increasing pressure from overfishing, habitat degradation, and climate change has highlighted the need to establish fisheries reserves to promote sustainable resource use. This baseline study evaluated fish assemblages, specifically species composition, diversity, and catch per unit effort (CPUE); across five fisheries reserves located along the Zambezi River (Sitwela, Kabweza, and Makangala) and the Kwando River (Luhingi and Qhuqhumupa). Gillnet surveys using both experimental and monofilament gillnets were conducted between 13 November and 13 December 2021. A total of 3,360 individual fish, representing 32 species, were captured. On the Zambezi River, Makangala had the highest species richness with 24 species, followed by Sitwela with 21 species, and Kabweza with 20. On the Kwando River, Luhingi recorded 17 species, while Qhuqhumupa had 12. There was no statistically significant difference in species diversity among the reserves (H(4)=8.268, p=0.082). However, overall CPUE (by weight) varied significantly between sites (H(4)=46.621, p<0.001), with Luhingi showing the highest CPUE (0.704±0.78 kg/set) and Kabweza the lowest (0.209±0.14 kg/set). Significant differences in individual CPUE were observed for two commercially important species: Clarias gariepinus(H(4)=26.783, p<0.001) and Clarias ngamensis (H(4)=17.967, p=0.001), while no significant variation was found for Serranochromis macrocephalus (H(3)=0.260, p=0.967). Similarly, mean fish sizes for C. gariepinus (H(4)= 25.850, p<0.001) and C. ngamensis (H(4)=14.660, p=0.005) differed significantly across sites, whereas no difference was noted for S. macrocephalus (H(3)=0.779, p=0.885). Regression analysis showed that temperature had no effect on fish catch rates. However, reserve size explained 14% of the variation in catch rates. These spatial differences in catch rates for key commercial species may be influenced by factors such as the degree of protection, age, and size of the reserves. In particular, higher CPUEs in the Kwando River reserves may be attributed to stronger protection measures and longstanding conservation awareness compared to the more recently established reserves along the Zambezi River. These findings underscore the need for tailored, site-specific management strategies to ensure the sustainability of fish populations across all five newly established fisheries reserves in the regionItem Comparing the effects of two types of Mulches on soil properties and the performance of selected woody species on a degraded land in Kunene region, Namibia(University of Namibia, 2025) Ndatipo, Simon K.; Nesongano, WellenciaLand degradation in arid and semi-arid regions has put tremendous pressure on rangelands, reducing their ability to provide important ecosystem services and sufficient forage for livestock. Given the increasing pressures on rangelands, it is of utmost importance to find ways to restore degraded rangelands. Incorporating mulching treatments into ecological restoration plans could aid in establishing diverse and resilient plant communities and enhance the long-term success of restoration projects. The present study sought to determine the effects of two types of mulching materials (leaf litter and straw) on the soil's temperature, moisture content, and pH as well as the cumulative stem length, seedling survival, and leaf chlorophyll content of the selected species (Faidherbia albida, Catophractes alexandri, Vachellia erioloba, and Senegalia galpinii) during three watering periods (once-daily, twice-weekly and once-weekly). A 5 x 5 block grid was used with treatments (control, 5cm leaf litter, 10cm leaf litter, 5cm straw, and 10cm straw) assigned randomly and within each treatment the species were assigned randomly to holes. Mulching significantly reduced soil temperatures and retained soil moisture content but did not influence soil pH during the course of the study. Amongst the various treatment combinations tested, both 10 cm mulch depths (straw and leaf litter) appeared to be the most effective in terms of optimizing soil conditions, seedling growth, and survival for Senegalia galpinii, Catophractes alexandri, and Faidherbia albida. During the twice-weekly watering period, Vachellia erioloba seedlings grew much better in the control blocks than in the two 5 cm mulch depths (leaf litter and straw), but their seedling survival rate was unaffected by mulching throughout the study period, indicating that mulching had no positive effect. These findings could be attributed to the fact that Vachellia erioloba is a phreatophyte, which means that it can excess groundwater in water i stressed environments (possibly very early on) and that mulching has a lower impact on its survival and growth, making the shallow effect of mulching on it less noticeable. Mulching had no effect on the leaf chlorophyll content of Senegalia galpinii, Catophractes alexandri, or Faidherbia albida but significantly increased chlorophyll content of Vachellia erioloba at both straw mulching depths, suggesting a positive species-specific response in V. erioloba’s photosynthetic rate towards mulching with straw. This study concludes that using leaf litter or straw mulch at 10 cm depths can improve soil conditions for plant growth and help restore degraded regions, and that some of the plant responses to the different mulching treatment combination may be species specificItem The effects of neighbor, distance, and organic fertilizer on the establishment and early performance of three woody species in a restoration trial in the Kunene region, Namibia(University of Namibia, 2025) Akomena. Soini N.; Inman, EmiliaLand degradation poses a significant challenge in arid ecosystems across Africa, adversely affecting the livelihoods of many who depend on the environment. It has become an urgent priority to restore these ecosystems. While various restoration approaches have been studied globally, few have explicitly considered how neighboring plant species and plant spacing as well as organic fertilizer influence restoration outcomes. This study evaluated the effects of neighbor identity, planting distance, and organic fertilizer on the growth, survival, and leaf traits of three woody species – Vachellia erioloba, Colophospermum mopane, and Combretum imberbe. Experiments were conducted in outdoor and indoor environments using a "two-factor (2x9) complete randomized factorial design" with nine neighbor combinations and two levels of distance/fertilizer. Results from field experiments showed that neighbor effects varied by species. C. imberbe experienced improved stem length and biomass when paired with V. erioloba, while C. mopane had reduced survival when grown with V. erioloba at close spacing. Leaf nitrogen and surface area were generally lower when species were paired with heterospecific neighbors, with V. erioloba exerting the strongest influence. Wider spacing (1 m) enhanced growth and leaf traits for most species, although the impact on survival and nutrient uptake varied depending on species. In the greenhouse, manure produced mixed results, enhancing leaf traits for C. imberbe and V. erioloba when grown alone or with conspecifics, but reducing growth and survival in the presence of heterospecific neighbors. Recruitment of native species was positively associated with C. mopane and C. imberbe, especially under 1 m spacing, while V. erioloba showed a negative association. These findings could inform future revegetation initiatives and help design planting strategies that enhance target species performance in restorationItem Assessing land degradation through a participatory approach in selected villages of the Kunene region, Namibia: Bridging scientific and local knowledge bases(University of Namibia, 2025) Hasholo, Ndapanda; Imnan, Ndeinekela EmiliaWhile scientific methods for assessing land degradation are well established, they often overlook indigenous knowledge provided by local communities. This study utilized a participatory approach to assess land degradation in Otjamaungu and Otjimbundu villages in Kunene region, Namibia, which is among the regions considerably affected by land degradation. Communities identified sites that they perceived to represent five distinct degradation categories: very low, low, moderate, high, and very high. For each category, three sites were selected, and within each site, three plots measuring 20 m × 20 m were established. Vegetation assessments in each plot included measurements of species richness, species diversity, plant density, total basal area, regeneration capacity, and herbaceous cover. Soil assessment included compaction, soil erosion and fertility. Furthermore, local perceptions on land degradation was captured. Ecological results were compared with opinions and perceptions by the communities regarding degradation. The results indicated that community-defined degradation categories were strongly influenced by visible vegetation cover, with denser vegetation typically associated with lower degradation levels. Overall, scientific data largely aligned with community classifications. Quantitative data were analysed using R Studio, while qualitative data were analysed using thematic analysis. Significant differences in species richness, diversity, density, total basal area, herbaceous cover and regeneration capacity were observed between degradation categories in both villages (P<0.05). Interviews revealed that communities primarily perceived land degradation through its impact on livestock, central to their livelihoods, rather than through broader ecological consequences.. Perceptions of degradation varied within villages, with some individuals demonstrating limited understanding of its causes and manifestations . By combining scientific expertise with local knowledge, this study enhances the understanding of land degradation in the Kunene region, paving the way for more effective conservation and restoration effortsItem Determinants of wet season landscape and forage selectivity by cattle on farm Kiamsab West 364, central Namibia(University of Namibia, 2025) Dube, Sijabuliso; Mapaure IsaacForage shortages are increasing in frequency and severity, affecting livestock farmers in Namibia. Cattle grazing preferences are well documented in various ecosystems but remain unknown in patchy, arid environments. This study investigated the determinants of forage and landscape selectivity by cattle during the wet season at Farm Kiamsab West, Central Namibia. Transects were demarcated on crests (n = 12, 72 plots) and slopes (n = 13, 78 plots) based on where cattle had been observed grazing, grazing signs, and accessibility. In each plot, species were identified to species level, grazing status was recorded, cover was visually estimated, and above-ground biomass was collected. Forage selectivity was determined with Jacob's Selectivity Index (JSI). Percentage slope, elevation, species richness, species diversity (H'), cover, and biomass were explanatory variables in the Canonical Correspondence Analysis (CCA) to identify landscape selection determinants. The Chi-Square Test of Association revealed that cattle exhibit selective foraging behaviour (χ² = 17.416, df = 2, p = 0.001). The JSI demonstrated that cattle selected grasses such as Eragrostis nindensis, Anthephora pubescens and forbs Cleome suffruticosa, and Tribulus terrestris. Forage selectivity is linked with plants’ nutritional value, palatability, and availability in the landscape. The CCA showed that explanatory variables explained 36.7% of the observed variation in landscape-type selection. The overall test of all canonical axes (F = 1.4, p = 0.002) was significant, with elevation (F = 1.9, p = 0.004), species richness (F = 1.6, p = 0.014), and slope (F = 1.6, p = 0.02) significantly influencing landscape-type selection. These determinants influence forage accessibility, availability and determine the balance of costs and benefits for selecting a landscape type, guiding cattle to forage where benefits outweigh effort. These findings inform targeted rangeland management strategies to promote preferred species, emphasizing ii the importance of prioritizing richness, elevation and slope in managing mountainous rangelandsItem Identification, mapping and ranking of important plant areas in Oshana, Oshikoto, Omusati and Ohangwena regions in Namibia(University of Namibia, 2024) Andreas, Emilia Ndapandula; Kwembeya, Ezekeil GwinyaiThe identification of IPAs (Important Plant Areas) has been at the forefront of conservation research in recent years however, there is no recent information on the IPAs in Namibia. Thus, the aim of this study was to identify, map, and rank the IPAs in the study regions using the IPA criteria established by Darbyshire (2017) and validate those demarcated based on expert knowledge (hereafter referred to as preliminary IPAs). New IPAs were identified using the global IPA criteria following Blasi et al. (2011) and Darbyshire et al. (2017). Similarly, preliminary IPAs were validated using the global IPA criteria. IPAs were ranked in terms of their conservation importance using a grid-based ranking system. QGIS software was used to produce maps for new IPAs. In addition, current protected areas and non-protected areas do not differ significantly in terms of species richness based on this standard scoring method. Consequently, Cluster analysis produced four clusters with 10% similarity in species composition, indicating huge differences in species composition between protected and non-protected areas that satisfy the IPAs criteria. QDS with high conservation scores were identified as the new IPAs instead of the previously demarcated IPAs. This study recommends stakeholders, practitioners, and policymakers to prioritize IPAs that are not in protected areas for conservation. Additionally, this study revealed the effectiveness of identifying and recognizing IPAs using globally standardized IPA criteria and expert-opinion-based selection aloneItem Fish species composition, fish sizes and diversity in the Kamutjonga floodplain, Kavango river, Namibia(University of Namibia, 2023) Libala, Stellah Naumi; Hay, ClintonFloodplains are amongst the most productive aquatic environments on earth providing valuable ecosystem services to communities such as being a valuable protein source for marginalized communities. This study ultimately aims to provide information on the fish species composition, fish sizes and species diversity in the Kavango River’s Kamutjonga floodplain as a basis to provide management advice to ensure the sustainable use of the fisheries. The fish species composition and relative abundance were assessed in the Kamutjonga floodplain along the Kavango River between February and April 2017, February to June 2018 and February to June 2020. Fish sampling was carried out once weekly using a seine net. A total of 2924 fishes were collected in 2017, 1678 fishes in 2018 and 4461 in 2020. The catch per unit effort (CPUE) by number was higher in 2017, followed by 2018 and lastly 2020. 31 fish species from 10 families, 37 species from 11 families and 31 species from 9 families were identified in 2017, 2018 and 2020 respectively. The Cyprinidae family was most prominent in the catches in 2017 and 2020, whereas the Cichlidae family dominated the catches in 2018. According to the index of relative importance, the most important species according to number in 2017, 2018 and 2020 were Oreochromis andersonii comprising of 47.7%, 27.1% and 49.6% of the total catches, respectively. The total weight of fishes collected in 2017, 2018 and 2020 were 6.404 kg, 5.963 kg and 11.456 kg respectively. The two most important fish species according to weight throughout the sampling period were O. andersonii (2.990 kg in 2017, 2.300 kg in 2018 and 6.273 kg in 2020) followed by Hydrocynus vittatus (1.546 kg in 2017, 1.915 kg in 2018 and 1.076 in 2020). The highest weight of fish was found in 2020, however, the catch per unit effort (CPUE) by weight was highest in 2018, followed by 2017 and then 2020. The majority of Oreochromis andersonii sampled were between the length classes 41 mm to 50 mm (n = 489) in 2017, 61 mm to 70 mm (n=89) in 2018 ii and 31 mm to 40 mm (n=606) in 2020. The majority of Coptodon rendalli sampled were found between the length classes 51 mm to 60 mm in 2017, 21 mm to 30 mm, 41 mm to 50 mm in 2018, and 41 mm to 50 mm in 2020. The majority of Hydrocynus vittatus sampled were found between the length classes 51 mm 59 mm (n = 54 mm) in 2017, 71 mm to 80 mm (n = 48) in 2018 and 31 mm to 34 mm (n = 68 mm) in 2020. This study found no significant difference in fish species diversity between years. The water level of the Kamutjonga floodplain had an influence on the catch rates, however, the water temperature did not affect the catch rates (catch per unit effort by number) in all the three years of samplingItem Comparing tree functional traits and species diversity along an increasing rainfall gradient in northern Namibia(University of Namibia, 2025) Shikongo, Albertina M.N.; Fabiano, E.Changes in precipitation patterns have the ability to affect the composition and the variety of species within a plant community by altering their functional traits. However, there has been a tendency to underestimate the importance of functional diversity. This is particularly common in Namibia, despite a clear, gradient in precipitation and where forecasts have predicted changes in precipitation regimes in the future. This study examined how tree species diversity and functional traits changed along an increasing rainfall gradient in northern Namibia. It employed a quantitative approach with systematic sampling at 13 points along an approximately 1200 km transect. Tree species diversity fluctuated along the gradient and average annual rainfall did not appear to have a significant effect, yet species diversity was highest at sites with high rainfall. There was no statistical difference in the species diversity among sites, but the estimated beta diversity was high. Plant functional diversity indices and plant functional traits varied along the gradient. All three functional diversity indices revealed weak relationships with species diversity. Among the three functional diversity indices, only functional richness was significantly affected by annual average rainfall. While the current study presents some contrasting results, it remains relevant by providing an understanding of the dynamics between plant species diversity and functional diversity. The results of the current study support the conclusion that plant species diversity and plant functional diversity are both vital components of ecosystem functioning, and that future research should incorporate a wider array of functional traits and use more comprehensive data collection methods that can build on the findings to further elucidate these complex interactionsItem The presence, diet and relative abundance of otters (Carnivora: Mustelidae) in Northern Namibia(University of Namibia, 2023) Abiatar, Yeholendjeshili Laina N.; Eiseb, Seth J.Four species of otters (Carnivora: Mustelidae) are known to occur in Africa: Eurasian otter Lutra lutra, spotted-necked otter Hydrictis maculicollis, African clawless otter Aonyx capensis and the Congo clawless otter Aonyx congicus. The African clawless and Spotted-necked otters are known to occur in Namibia although very little is known about their biology and distribution. IUCN Red List of Threatened Species indicated the status of African clawless and spotted-necked otters to be near threatened due to a reported decline in their numbers primarily due to habitat loss and destruction, mainly from unsustainable agricultural land expansion, human and otter conflict, invasive species, river pollution as well as widespread continent-wide decrease in river water quality. The collection and use of faecal samples and camera trapping have become an important non-invasive source of information, especially when dealing with elusive animals. The specific objectives of this study were to determine the presence of otter species that occur in the Kunene and Okavango rivers, their diet as well as their relative abundance. Community sightings of otters were utilized, along with on sight observations (for example, sightings and signs) while collecting data in the field to determine the presence of otter species. Sightings of the African clawless and Spotted-necked otters, as well as signs (footprints) of the two species of otters were recorded as an indication that both species do occur in Namibia. In order to determine the diet of otters, spraints were collected along the banks of the two rivers, air dried, teased apart and prey remains identified by utilizing a stereomicroscope. Prey remnants were sorted into major categories and recorded. Prey items such as crabs, frogs, fish, plant material and insects were found in the otter spraints. Due to the small sample size of spraints collected, it could be possible that not all potential prey items were available for recording. A total of 40 cameras were deployed along the banks of the Okavango River within the Bwabwata National Park, recording a total of 967 camera days. Due to extremely low detection of the Spotted iii and African clawless otters (3 encounters), no density estimates were computed. Instead, a relative abundance index (RAI) of 0.3 of African clawless otter was calculated and compared to RAIs data obtained from six natural areas around Southern Africa. Results suggest that the Relative abundance index (RAI) of 0.3 for the Okavango River was the lowest compared to similar studies done elsewhere in southern Africa. A species accumulation curve for all mammals photo-captured in the study area was plotted which nearly reached an asymptote (with 21 captured species), suggesting that the inventory on species composition in this phase was more complete. Conservation of the wetlands and restoration of water quality might be the most important steps towards ensuring the future of otters in Namibia. There is also a need for a more expansive study to be conducted on the taxonomy, distribution, diet, and population density of otters that occur in all northern perennial rivers of Namibia.Item Consumptive forest use and spatio-temporal abundance of wildlife in George Mukoya and Muduva Nyangana Community Conservancy in Northern Namibia(University of Namibia, 2024) Liyeke, Miriam Mambo; Rutina, L. P.Forests are important to people because they provide socio-economic and ecological goods and services such as the use of poles for building materials and income through selling. Studies have shown that the degradation or loss of forests has a direct impact on wildlife. In rural areas of Namibia, some forests on communal land are managed by the local communities to provide socio-economic benefits. If not well managed and the use is not sustainable (inappropriate use), may undermine the long-term ecological value of forest resources including wildlife. The Khaudum north complex conservancies (George Mukoya and Muduva Nyangana) were established in 2005 and community forests were gazetted in 2010. In the year 2012, the government of Namibia through the Ministry of Environment Forestry and Tourism integrated the wildlife conservancies and community forests, with the aim of harmonising the two land uses. Since then there were no studies to assess the community forest use on wildlife species and their habitat thus the need to conduct this study. This study used both quantitative and qualitative methods to collect data. Data on wildlife species abundance and distributions were collected from conservancies’ event books and game counts. Interviews were used to gather community perceptions on the consequences of their livelihood strategies on wildlife. A sample size of 293 respondents was obtained from the two conservancies. To assess the change in wildlife species abundance, the regression analysis with yearly wildlife group size as a dependent variable was applied. The distance from nearby settlements, fire intensity, and vegetation cover change as continuous independent variables; and conservancy (George Mukoya and Muduva Nyangana), species category (carnivores and herbivores), land use (multiple use and wildlife exclusive zones) and season (dry and wet) as categorical variables. Satellite images were used to analyse vegetation cover change and accumulated fire intensity using change detection analysis and empirical Bayesian kriging interpolation. Average group size means, and standard errors were calculated and used to determine the associations ii among variables. Contingency tables were used to analyse respondents’ perceptions of the influences of livelihood strategies and major socio-economic activities on wildlife. Generally, results showed a decrease in wildlife numbers in the study area between 2013 and 2017 (P <0.001). This was positively associated with vegetation change (P =0.032) and species category (P < 0.001), negatively by distance from settlement (P = 0.004) and land use (P < 0.001), but was not fire intensity (P = 0.714) and locality (conservancy) (P = 0.170). Carnivore density distribution was evenly spread in relation to distance from settlements, fire intensity, and vegetation change but was more in a wildlife-exclusive zone than the multiple-use zone. Herbivore distribution was denser in the wildlife-exclusive zone, more in areas where vegetation cover was high, and increased with increasing distance from settlements, but was not influenced by fire intensity. In both conservancies, the majority of respondents were either dependent on crop production (53%) or a combination of crop production and livestock (30%), with only 18% depending on other livelihood strategies. When asked what is the impact of their livelihood strategies on wildlife and its habitat, 75%, 17%, and 8% of the respondents said there no impact, impact, or no awareness, respectively. When the community was asked, what is the impact of the services they get from forestry on wildlife and its habitat, 73% of the respondents said there was no impact whereas 27% indicated that there was a significant impact. The study showed that the communities of George Mukoya and Muduva Nyangana are aware of the conservation issues in their areas and can manage wildlife successfully themselves.Item The effect of gracilaria verrucosa on the growth rate of pacific oyster (crassostrea gigas)(University of Namibia, 2002) Hipandulwa, GabrielIn natural aquatic systems, there are ecological balances between different species of organisms and individuals. However in culture conditions the systems are usually meant to favour the preferred organisms, but still other organisms might invade and share in the utilization of resources. Gracilaria verrueosa i an unwanted plant that grows in marine cultured beds along the Namibian coast and this experiment showed that it adversely affects the growth performance of the Pacific oyster ( Crassostrea gigas). The decrease in growth of the oyster in rafts was directly linked to the presence of Graci/aria verrucosa. This experiment quantitatively showed that invasion quantities of Graci/aria verrucosa influences the percentage growth reduction rates of oyster. The various seeding rates (0, 400, 800 g) of Graci/aria verrucosa resulted in significantly (P>0.05) reduced growth rates of oysters by 21 % and 37¾ in medium and high seeding rates of the seaweed, respectively. This was shown to be significant using the t-test and Wilcoxon Sum Rank Test (P>0.05). Although conducted over a short growing period of 6 weeks, the experiment demonstrated detrimental invasion of Graci/aria verrucosa in oyster raftsItem Assessing the potential of agritourism at Neudamm, Namibia(University of Namibia, 2023) !Gaeb, Manfred DonavonThe share of the agricultural Gross Domestic Product (GDP) in Namibia is lower than that of the average Sub-Saharan Africa. Correspondingly, is the share of agricultural labour force, which has also, been declining since the country’s independence (Mushendami, Biwa and Gaomab 2008). The University of Namibia (UNAM) experienced this reality, primarily, through potential of income generating opportunity at Neudamm Campus. As a result of this precarious condition, and the declining of UNAM’s government subsidy, the university had to explore alternative income streams. One such alternative avenue is the agritourism opportunity at Neudamm. Very few studies have so far assessed agritourism factors of success in global north whilst global south lack such studies. This gap in literature in assessing agritourism factors of success in the global south necessitated this study. The research concluded firstly, that economic factors are not the only determining factors of successful agritourism but also social factors. Secondly, the findings established that Neudamm suffers from several shortcomings and therefore, potential viable agritourism cannot be achieved without addressing those shortcomings. Thirdly, critical success factors of agritourism were found to be natural bonding dynamics of various forms of capital. As a result, the study recommended nomination of Neudamm as a place of heritage importance due to its historical importance. Furthermore, policy directives such as Affirmative Action Loan Scheme (AALS) and National Agricultural Credit Program (NACP) need urgent review thirty two years after Namibia’s independence, to foster national reconciliation. Additionally, the implementation of agritourism concept at farm Neudamm is fervently advised by addressing shortcomings and adding tangible visionary stage for the TALC model during agritourism destination development process is proposed.Item Implementation of political and socio-economic strategies in urban housing-land delivery within the Municipality of Windhoek(University of Namibia, 2023) Kahungu, Fransina NdateelelaThe Municipality of Windhoek has been faced with challenges relating to the slow pace of the allocation of affordable land to the people and inadequate servicing of housing land. This has, over the years, created and widened the gap between demand and supply, hence the ballooning of the number of people in Windhoek who are on the waiting list for serviced land. It has been suggested that the solution to the provision of serviced land for housing lies in the implementation of multiple strategies. While the City of Windhoek has strategies in place, no studies have been done to understand whether these strategies have been successful. The aim of this study was therefore to investigate and analyse the implementation of the political and socio-economic strategies for land distribution within the Municipality of Windhoek from 2007-2019. The study adopted a qualitative research approach taking the City of Windhoek as the case study for investigating and analysing the implementation of the political and socio-economic strategies for land distribution for housing. The population for this study included stakeholders involved in land distribution in Windhoek. Study participants were selected through purposive sampling, identifying those participants with the capacity to provide information relevant to the study. Data was collected using interviews. Results of the study showed that land allocation delays and land shortages have been caused by factors such as lack of finance, unavailability of serviceable land, rigid municipal procedures and unbalanced demand and supply. The study also found that the Municipality of Windhoek is encountering major problems which include a shortage of serviced land, high land servicing costs, and a cumbersome land allocation process. Given these findings, the study recommends that government avails finance to assist local authorities to increase the supply of serviced residential land. Some of the finance should also target the upgrade of informal settlements so that they reach the stage of security tenure. In addition, the Windhoek municipality should review land distribution methods to ensure that households in dire need of housing are given priority.Item An assessment of the trends in population abundance and spatial distribution of roan antelope (Hippotragus equinus) and sable antelope (Hippotragus niger) in the greater Waterberg plateau complex, North-central, Namibia(University of Namibia, 2022) Alfeus, MarthaUnderstanding factors affecting the demographic status and spatial distribution of large mammals is of major relevance in wildlife conservation and management. This is particularly the case for the roan (Hippotragus equinus) and the sable (Hippotragus niger) populations in the Waterberg Plateau Park (WPP) whose growth appears to have been suppressed since 1994, after being introduced in 1975 and 1980, respectively. The lack of scientific assessments on potential factors influencing their growth and spatial distribution has been a major challenge confronting their management in the WPP, which is the aim of this study. The study used the Generalized Additive Modelling and State Space Models to assess trends in the abundance of roan and sable between 1975 and 2019 in the WPP based on historical aerial count data. Additionally, occupancy modelling and detection probability was conducted to assess the influence of site and detection covariates on their spatial distribution in the Waterberg Plateau Farm based on the camera trapping data collected during the wet and dry seasons. The study estimated with uncertainty a negative population growth for roan (r = - 0.02 ± 0.06, CI95 = -0.13 – 0.09) and a zero-population growth for the sable (r = 0.00 ± 0.08, CI95 = -0.14 – 0.16). These growth trajectories tend to be positively influenced by annual rainfall, and the occasional auctioning, and the introduction of individuals. Contrary, it was insignificantly but negatively influenced by the low-lagged rainfall and the increase of the buffalo population. Occupancy modelling showed that roan distribution is significantly influenced by the co-occurrence of sable both during the wet and the dry seasons. Sable distribution was positively influenced by forage and the presence/absence of leopard during the wet season while positively influenced by the presence/absence of waterhole during the dry season. The cumulative effect of these variables is likely to have resulted in the reduction of the survival and reproduction rate as these antelopes are unable to escape the semi-closed isolated study areas. Future interventions involving the introduction of these species outside their native ranges should be careful thought, and must consider the potential impacts of climate change to improve the success of this management strategy.Item Public engagement in sustainable urban development: From engagement to co-creation through a smart city approach, Windhoek, Namibia(University of Namibia, 2021) Andreas, Elly DisneyThe City of Windhoek plays a unique role in the social and economic success of Namibia, as the center of international networks and where the government sits, this places a significant responsibility on national and local authorities to sustain the population. Globally, 55% of the world’s population lives in urban areas, a proportion that is expected to increase to 68% by 2050 (UN, 2018). This unparalleled rate of urban growth is creating an urgency to find smarter ways to manage the influxes of urban populations and public participation processes are considered and proven to be an important element for enabling successful sustainable development in a smart city concept because they involve actively engaging the civil society (Brand et al. 2013). This research study identifies current engagement tools used by the City of Windhoek (CoW) and evaluates how they are implemented in practice. Through semi-structured interview sessions and participatory observations at identified public engagement meetings, findings prove that traditional engagement mechanisms, such as public meetings, are still commonly used by the City of Windhoek. City planners are developing their engagement toolbox in order to strengthen public participation, and in turn, reach an audience that reflects and represents the contributions made by the population in urban sustainable development plans. The extent to which engagement tools are resulting in outcomes that are inclusive and representative to the public is difficult to determine because the CoW’s planning division does not require to track the participant’s demographics at public meetings. Reviewing the City of Windhoek’s public participation policy to include indicators such as participants' gender, age, and attendance register to name a few would be a step in the right direction to maintain the new vision- “A Smart and Caring City by 2022”.Item Quantification and characterization of encroach bushes targeted for conversion into livestock feed at Neudamm farm, Khomas region, Namibia(University of Namibia, 2020) Shilume, Kaino TemapoBush encroachment is a serious problem in Namibia leading to significant reduction in livestock production and biodiversity. Harvesting encroacher bushes for conversion into livestock feed is a practice becoming more common. Every encroached area is unique in species composition and density of encroacher bushes and hence characterisation of such bushes is essential prior to laying out harvesting strategies. The main aim of this study was to determine the species composition and estimate the amount of feed-suitable biomass of the dominant species constituting encroacher bushes in Block G of Neudamm Farm. Landsat images (Landsat 5 TM and Landsat 8 TM) of the study site were used to stratify the area into low, medium and high bush density classes to assess how encroachment changed between 1989, 2000 and 2017. In the high bush density areas, bush densities, species composition, diversity and similarity were analysed in relation to site, topographical positions and soil properties. Data were gathered from 27 sample plots (2 x 50 m). There was a 14% increase in area covered by high bush density between 1989 and 2017. Senegalia mellifera had the highest density and biomass across all sites and at all topographical positions. Bush density differed significantly only between sites. Site 2 had significantly higher bush density than Sites 1 and Site 3. This higher bush density in Site 2 was contributed by presence of high numbers (in excess of 10000 plants/ha) of small sized trees and shrubs. Only Sodium had a negative correlation (Pearson correlation) with bush density at different topographical positions (p=0.3888), this could be because Na increases osmotic tension, by which water is held in the soil and as result the plant die-off. The total biomass of bushes varied significantly across sites (Kruscal Wallis Test, P=0.024 and biomass fit for animal feed varied significantly across Sites Kruscal Wallis Test, P=0.027). This variation is linked to variation in bush density since Site 2 which had the highest bush density also had the highest biomass. It is concluded that 4.8 tonnes/ha can be harvested by selectively removing S. mellifera. The study recommends harvesting of only S. mellifera as this would yield large amounts of uniform feed and preserve other rare species especially those being given special protection like Boscia albitrunca, Searsia lancea and Ziziphus mucronata. Similar studies are recommended for other areas where encroacher bushes are to be harvested.
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