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    Rich resources from poor communities: An analysis of Namibia’s access and benefit-sharing legislation
    (Elsevier, 2024) Nakanyete, Ndapewa F; Matengu, Kenneth K; Diez, Javier R
    Since pre-independence, Namibia has faced wealth disparities and unfair distribution of benefits arising from natural resources. Producers, who hold traditional knowledge related to genetic resources, continue to endure poverty. In response, the Government of Namibia collaborated with various stakeholders to develop access and benefit-sharing policies and regulations. This study aimed to investigate the effectiveness of access and benefit-sharing legislation in distributing monetary and non-monetary benefits from users of non-timber forest products to indigenous and local communities who produce them. To achieve this, we integrated the access and benefit sharing approaches with the value chain framework to identify gaps in the implementation of benefit-sharing. We employed a mixed-methods approach, incorporating semi-structured in terviews, participation in symposiums, and statistical data analysis. Our findings revealed that despite the established legislative measures aimed at improving the benefits for Namibian pro ducers, the actual sharing of the benefits remains unsatisfactory. Only a few communities that harvest non-timber forest products had benefit-sharing agreements or joint patent ownership with global or regional industries. Moreover, the San communities, who received incentives from the Devil’s Claw manufacturer in 2021, did not enter into any benefit-sharing agreements until March 2023. We suggest that the recently implemented access and benefit-sharing regulations may not fully address the benefit-sharing issues overlooked by previous policies and initiatives. Therefore, we recommend further studies in exploring the potential of establishing efficient non-timber forest product processing facilities to economically empower communities. This, will ultimately contribute to national economic growth and the achievement of sustainable development goals.
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    The impact of commodified non-timber forest products on the livelihoods of San in northern Namibia
    (Taylor and Francis, 2023) Nakanyete, Ndapewa F; Matengu, Kenneth K; Diez, Javier R
    In Namibia, the commercialisation of non-timber forest products (NTFPs) is often promoted as a means to improve rural livelihoods, especially for vulnerable communities. This paper analysed how NTFP value chains are integrated into and contribute to the livelihoods of Khwe and !Xun San harvesters. Accordingly, the working conditions, employment and upgrading opportunities of the globally traded Devil’s Claw were compared to those of regionally traded products, including Natal Oranges. Amixed-method approach was applied to collect data in Okongo Constituency and Bwabwata National Park. Findings revealed that while NTFPs contribute to the harvesters’ income generation, the income is insufficient to sustain their livelihoods. Interestingly, the results of both regional and global value chain integration do not lead to improved livelihoods. Further research is needed to analyse the synergies between the government, traditional and local authorities, NGOs, and other institutions in implementing laws that promote equitable sharing of benefits from NTFPs.
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    Spatio-temporal characterization of surface water dynamics with Landsat in endorheic Cuvelai-Etosha Basin (1990–2021)
    (Elsevier, 2022) Hamunyela, Eliakim; Hipondoka, Martin; Persendt, Frans; Nghiyalwa, Hilma Sevalia; Thomas, Chris; Matengu, Kenneth
    Socio-economic damages caused by extreme floods have been increasing rapidly in recent years, mainly driven by changes in the climate and modulated by increasing human population in deltic areas and floodplains. The Cuvelai-Etosha Basin (CEB) in southern Africa, covering southern Angola and northern Namibia, experiences socially and economically devastating extreme floods. Yet, accurate information on past and current surface water changes and dynamics is lacking. Here, we estimate and map the surface water extents in the CEB and its surroundings (CEB + S) for 32 years (1990–2021) from Landsat data using random forest models to provide long-term baseline information on surface water changes and dynamics. Based on the reference data, a total of 15,677 ± 1080 km2 have been inundated by surface water in the CEB + S during 1990–2021. This extent was accurately mapped by our local water extent product (mapped area = 16,273 km2, user’s accuracy = 91.5 ± 2.5%, producer’s accuracy = 91.1 ± 6%). With user’s and producer’s accuracy of 91%, our overall water extent provides the first most accurate long-term baseline information on surface water inundation in CEB + S necessary for local spatial planning processes to minimise future negative impacts of floods in the basin. Interannual variability of surface water extent is, however, high, with water extent ranging from 520.8 ± 375.7 km2 to 12372.3 ± 1154.7 km2 during the 1990–2021 period. The largest annual water extents (>10,000 km2) were recorded in 2006, 2008, 2009, 2011, and 2017, whereas the smallest extents (<1000 km2) were recorded in 1992 and 2019. We found that over 40% of the area inundated in the CEB + S during 1990–2021 was inundated less than 9 times. With human population increasing rapidly in the CEB + S, rarely inundated areas with short water residence could become a prime target for human settlements, which may lead to huge socio-economic damages during extreme floods if no preventive measures are put in place. Globally available surface water maps from the Global Land Analysis and Discovery (GLAD) and European Commission’s Joint Research Centre (JRC) did not provide realistic surface water extent for CEB + S, especially during years with extreme floods. Therefore, locally adopted product for operational monitoring of surface water in the CEB + S is needed to provide accurate information for informing spatial planning processes and surface water resource management strategies in this endorheic basin and help minimise future negative impacts of floods.
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    Could China’s journey of malaria elimination extend to Africa?
    (Infectious Diseases of poverty, 2022) Wang, Duoquan; Lv, Shan; Matengu, Keneth K.
    World Health Organization (WHO) certified China malaria-free on June 30, 2021, which brightens the goal of global malaria elimination efforts. China contributed its unique innovations to the global community: Artemisinin, discovered by Tu Youyou, has saved millions of lives globally; the “1-3-7” norm developed in 2012, has been adapted in the local contexts of countries in the Southeast Asia and Africa. How to the targets of Global Technical Strategy for Malaria (GTS) 2016−2030. By looking into the malaria control phase, towards elimination phase from 1960 to 2011 in sub Saharan Africa and China, we found that the gap in malaria burden will widen unless the interventions in Africa are enhanced. It is imperative to identify the key China–Africa cooperation areas on malaria control and elimination, so that synergized efforts could be pooled together to help African countries achieve the elimination goal. The practices from China malaria control and elimination efforts could be leveraged to fast-track malaria elimination efforts in Africa, which makes it possible that the China’s journey of malaria elimination extends to Africa.
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    Assessing the impact of wildlife on vegetation cover change, Northeast Namibia, based on MODIS satellite imagery (2002–2021)
    (Sensors, 2022) Gbagir, Augustine-Moses Gaavwase; Sikopo, Colgar Sisamu; Matengu, Keneth K.
    Human–wildlife conflict in the Zambezi region of northeast Namibia is well documented, but the impact of wildlife (e.g., elephants) on vegetation cover change has not been adequately addressed. Here, we assessed human–wildlife interaction and impact on vegetation cover change. We analyzed the 250 m MODIS and ERA5 0.25 0.25 drone and GPS-collar datasets. We used Time Series Segmented Residual Trends (TSS-RESTREND), Mann–Kendall Test Statistics, Sen’s Slope, ensemble, Kernel Density Estimation (KDE), and Pearson correlation methods. Our results revealed (i) widespread vegetation browning along elephant migration routes and within National Parks, (ii) Pearson correlation (p-value = 5.5 10􀀀8) showed that vegetation browning areas do not sustain high population densities of elephants. Currently, the Zambezi has about 12,008 elephants while these numbers were 1468, 7950, and 5242 in 1989, 1994, and 2005, respectively, (iii) settlements and artificial barriers have a negative impact on wildlife movement, driving vegetation browning, and (iv) vegetation greening was found mostly within communal areas where intensive farming and cattle grazing is a common practice. The findings of this study will serve as a reference for policy and decision makers. Future studies should consider integrating higher resolution multi-platform datasets for detailed micro analysis and mapping of vegetation cover change.
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    Source of lunette dune sediments: A geomorphic terrain analysis approach in Etosha National Park, Namibia
    (2004) Hipondoka, Martin; Busche, Detlef; Kempf, Jurgen
    The presence of so-called lunette dunes in the lee of pans in northern Namibia sprouted a discussion on the formation of the shallow basins related to them. These lunette dunes are made up of larger particles than those found in the pans, from which the sediments are thought to have originated. At Etosha Pan, this contradiction is compounded by the fact that the dunes are found on the northwestern and western side of the pan, whilst the prevailing dominant wind, believed to have played a formative role in their development, blows from the northeast. Ancillary data, in concert with high-resolution, multi-date satellite imagery were examined through the prism of geomorphic terrain analysis. The resultant indicators unequivocally point to the Ekuma delta, on the northwestern rim of the pan, in direct opposition to the pan floor proper, as the source of these dune sediments. It is therefore probable that coarser sediments found on the lee side of similar pans can be similarly explained as originating from former inlet deposition and not from wind excavation in the process of pan initiation as popularly held.
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    Fossil evidence for perennial lake conditions during the Holocene at Etosha Pan, Namibia
    (2006) Hipondoka, Martin; Jousse, H.; Kempf, Jurgen; Busche, Detlef
    ETOSHA PAN, A LARGE (4760km2), ENDORheic depression situated in north-central Namibia, has been claimed to be essentially a wind-deflated landform. The pan was assumed by some researchers to have developed under persistent semi-arid conditions,which were alleged to have prevailed in the region for at least the last 140 000 years. Recent field evidence points to the contrary. This evidence includes a significant number of fossils belonging to, amongst others, semi-aquatic antelopes such as sitatunga, which are diagnostically indicative of perennial lake conditions in the area. These species have previously never been reported from Etosha National Park, either as fossils or extant. Here we indicate the significance of these findings and their implications for the palaeo-environment of the Etosha region.
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    Chronology of sand ridges and the Late Quaternary evolution of the Etosha Pan, Namibia
    (2014) Hipondoka, Martin; Mauz, B.; Kempf, Jurgen; Packman, S.; Chiverrell, R.C.; Bloemendal, J.
    Etosha Pan, situated at the southern border of tropical Africa, is a vast endorheic plain in Namibia's semi-arid north. The most recent studies agree that the pan was the floor of a former lake with varying water levels. Here we explored this idea further by investigating the link between lake-level change and records of late Pleistocene and Holocene climate change. The varying lake levels were inferred through sediment analysis and optical dating of sand deposits that form ridges parallel to the current shore along the northern and western margins of the pan. Our results support the view that the sand ridges are shoreline deposits of an evaporitic lake. The ridges result from the interplay between intermittent river discharge and riverine sediment supply from the north, prevailing north-easterly wind and shore-parallel waves. Therefore they are a proxy for former levels of a perennial lake. We infer higher levels during the late Pleistocene and a drastic drop shortly after 10 ka. Since around 8 ka Etosha Pan was covered by a shallow water body. This lake water-level reconstruction is not in line with the histories of ITCZ migration and strength of Benguela current upwelling. We confirm that the linkages between the evolution of the Etosha Pan and the climate mechanisms driving hydrological changes in subtropical southwest Africa are poorly resolved and need further investigation.
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    14C dating of organic residue and carbonate from stromatolites in Etosha Pan, Namibia: 14C reservoir effect, correction of published ages, and evidence of >8-m-deep lake during the late pleistocene
    (2013) Hipondoka, Martin; Brook, George A.; Railsback, Bruce L.; Marais, Eugene
    Lacustrine stromatolites are layered accretionary structures formed in shallow water by cyanobacteria. They are a precise indicator of high lake limits and their morphology and structure provide an insight into paleoenvironments of the time. Previous research on lacustrine stromatolites from Etosha Pan in Namibia based on radiocarbon ages of carbonates were close to the limit of the method and did not account for any possible 14C reservoir effect. The ages were used to suggest that the basin was not extensively flooded during the last 40,000 yr. To assess the reservoir effect, the age characteristics of a stromatolite from Poacher’s Point were investigated by 14C dating both carbonate and organic residue from samples at different depths in the deposit. The ~15-cm-diameter stromatolite was separated into 12 zones from the center to the edge and block samples were cut from each zone; the carbonate and residual organic residue were dated separately. The carbonate ages ranged from 34,700 to 24,700 14C yr BP and the organic ages from 15,700 to 2500 14C yr BP. Ages generally increased with increasing distance from the surface of the deposit. We believe that the organic ages are an accurate estimate of the stromatolite’s age, while the much older carbonate ages reflect incorporation of old carbon from limestone bedrock and ancient calcrete introduced by stream and spring flow. Excluding the 2 oldest organic ages (15,700 and 13,600 14C yr BP), which may reflect contamination by older organic material washed into the lake during flooding, a linear regression relationship between carbonate and organic ages indicates that the reservoir effect on carbonate ranges up to ~24,000 14C yr BP but decreases slightly as the true age of the deposit increases. This regression relationship was used to correct 2 finite carbonate ages for stromatolites from Pelican Island obtained in the early 1980s, which together with our new organic age for a stromatolite from Andoni Bay, document a >8-m-deep lake in Etosha Pan during the Late Pleistocene, at and prior to ~34,000–26,000 cal yr BP. The organic carbon ages from the Poacher’s Point stromatolite suggest prolonged lacustrine conditions during the early to middle Holocene (8000–6600 cal yr BP) but not to the extent seen during the Late Pleistocene
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    The potential of rainwater harvesting: A case of the City of Windhoek, Namibia
    (2013) Nashima, Festus P.; Hipondoka, Martin; Iiyambo, Inekela; Hambia, Johannes
    Windhoek, Namibia’s capital has experience for more than 25 years of novel approaches in integrated water management largely driven by the scarcity of water in the area. Notably absent in their approaches how ever, is the rooftop rainwater harvesting which is regarded as one of the viable alternative sources of water for domestic use. This paper assesses the potential economic benefits for rooftop rainwater harvesting for the City of Windhoek. Th e rooftop areas from four representative formal suburbs of Okuryangava ( low income) in the north, Academia (middle income) in the south-central, Pioneers Park (middle income) in the south-west and Ludwigsdorf (high income) in the east, were estimated from high resolution satellite images captured from Google Earth. These estimates were used to extrapolate for the potential amount of rainwater that can be harvested in an average rainy season (i.e. December to April) in the study area. The estimated harvestable amount for each residential area was developed using a simple model that incorporates total rooftop area and estimated rainwater. The derived figure was then expressed in terms of cost per unit prices charged by the City of Windhoek. Pioneers Park attests to have the highest (134 m3) potential harvestable rainwater per household, while Okuryangava is estimated to harvest the least amount of 36 m3 per raining period. Given the high density of erven, however, Okuryangava has a potential to harvest approximately 920484 m3 of water per hectare, ranking this suburb second after Academia, which stands at 1120716 m3. This is a significant amount of water effectively taken from rainwater rooftop that could also provide justifiable saving to residents if used instead of tap water. It is therefore recommended that the City of Windhoek actively promotes rooftop rainwater harvesting for the benefit of residents and also as a measure to reduce storm-water runoff due to urban development.
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    The changing climate and human vulnerability in north-central Namibia
    (2016) Angula, Margaret; Kaundjua, Maria B.
    North-central Namibia is more vulnerable to effects of climate change and variability. Combined effects of environmental degradation, social vulnerability to poverty and a changing climate will compromise subsistence farming in north-central Namibia (NCN). This will make subsistence and small-scale farmers in the region more vulnerable to projected changes in the climate system. Thus, the aim of this article was to examine factors contributing to subsistence farmers’ vulnerability to impacts of climate change. The article further discusses different aspects of human vulnerability and existing adaptation strategies in response to impacts of climate related disasters experienced over the past three to four decades in NCN. Qualitative and quantitative research approaches and methodology were employed to obtain information from subsistence farmers in north-central Namibia. The sociodemographic characteristics of Ohangwena, Oshana and Omusati Region reveals high levels of unemployment, high adult and elderly population and high dependency on agricultural livelihood system. These indicators help understand levels of household vulnerability. The study concludes that households interviewed revealed low levels of adaptive capacity due to exposure to climate risks and combined effects of social, political and cultural factors. This article provided an understanding that is required to inform the adaptation pathways relevant for NCN.
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    A large proportion of Micromys minutus in winter diet of the Long-eared Owl Asio otus
    (Walter de Gruyter GmbH, 2012) Kopij, Grzegorz; Moska, Magdalena; Nikiel, Remigiusz; Kozyra, Katarzyna
    A large proportion of Micromys minutus in winter diet of the Long-eared Owl Asio otus is discussed
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    Changes in numbers of Lesser Kestrels Falco naumanni and Amur Falcons F. amurensis at a winter roost in Lesotho
    (African Bird Club, 2012) Kopij, Grzegorz
    Over the last 20 years drastic changes have been recorded in the composition of a flock of Lesser Kestrels Falco naumanni and Amur Falcons F. amurensis at a roost on the campus of the National University of Lesotho at Roma. Numbers of the latter have increased, while those of the former species have dramatically decreased. Changes in the number of Amur Falcons recorded in February – March suggest that their southward migration continues until early February and soon thereafter a departure north starts, with most birds vacating the roost in the first half of March. The earliest arrival of Lesser Kestrel was 26 October, the latest departure 9 April. The earliest arrival date of Amur Falcon was 19 December, the latest departure date 7 April. Early-morning departure from the roost lasted for up to 40 minutes, but most birds left during the first 5–10 minutes
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    Diet of the Lesser Kestrel Falco naumanni in Israel
    (Taylor & Francis Group, 2012) Kopij, Grzegorz; Liven-Schulman, I.
    The food of the Lesser Kestrel (Falco naumanni) was studied by means of pellet contents analysis. A total of 645 entire pellets was collected, 550 pellets from the urban area of Jerusalem, 71 pellets from a rural area (a farmland) in Alona Region, 12 pellets from a natural area in the Judean Desert and 12 pellets from a quarry near Rosh Hain. Grasshoppers (Orthoptera), beetles (Coleoptera) and sun spiders (Solifugae) constituted the bulk of the diet. Numerically, grasshoppers and beetles were almost equally important (38.5% and 42.2% respectively), while sun spiders were much less numerous (11.7%). However, in terms of biomass, grasshoppers (54.7%) were far more important than beetles (18.8%) and sun spiders (20.6%). Four beetle families, viz. Carabidae, Scarabaeidae, Curculionidae and Tenebrionidae, comprised together 76.8% of all beetle prey items and 81.6% of beetle biomass. Among grasshoppers, the most important family (64.6% by numbers of prey items, 70.4% by grasshopper biomass) was the locusts (Acrididae). Significant month-to-month variations in the proportion of the main prey groups have been recorded. From February to April the Lesser Kestrel fed mainly on beetles, while from May to July it fed mainly on grasshoppers and sun spiders. Beetles and sun spiders comprised a much lower proportion of prey in 1998 (low rainfall) than in 1999 (high rainfall), while the proportion of grasshoppers and other invertebrates (altogether) was higher in 1998 than in 1999
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    Variation in composition of crude bark extract of Prunus Africana in different provenances of Kenya
    (Taylor & Francis, 2012) Gachie, P.K.; Koech, E.K.; Simons, A.J.; Ndalut, P.K.
    Prunus africana’s bark extract is used in treatment of prostate gland disorders among other uses. The dwindling of the species abundance in the wild necessitates its domestication. The first step is identification of desired germplasm. In this study, bark extracts from different Kenyan forest zones were compared for yield and chemical composition. Extraction was done using Debat (1974) procedure, while chemical composition was determined using chromatographic procedures. The extract yield showed a positive correlation with tree age, the best source being medium sized trees (30–50 cm dbh). Timboroa provenance had the highest extract yield (1.9%) while Kobujoi had the least (0.73%). Gas Liquid Chromatography analysis showed that Kakamega’s extract had the highest number of compounds (8) and Eburu had the highest b-Sitosterol content. With Thin Layer Chromatography, Kinale provenance showed the highest number of compounds (11). The species diversity is therefore important for breeding purposes and should be conserved.
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    Overlap in soil water sources of savanna woody seedlings and grasses
    (John Wiley & Sons, 2012) Kambatuku, Jack R.; Cramer, M.D.; Ward, D.
    Seasonal availability of water is a key controlling factor in semi-arid savanna vegetation structure, function and interactions. Understanding of woody plant interactions with grasses in savannas has long been underpinned by Walter's two-layered niche differentiation hypothesis that postulates that grasses and trees source water from different depths. The Walter hypothesis persists in the literature, despite contrary evidence and a lack of quantitative empirical tests of the theory. We conducted a greenhouse experiment to determine the following: (1) whether tree seedlings and grasses obtain water from different depths on rocky and sandy soils; (2) whether interspecific competition affected tissue water content of clipped grasses; and (3) the influence of repeated grass clipping on soil moisture. Grass competition significantly reduced tree seedling rooting depth on both rocky and sandy substrates. Trees had significantly longer roots on rocky substrates than on sandy substrates for all combinations (trees only, trees with unclipped grasses and trees with clipped grasses). Results indicated a three-tier soil moisture depletion pattern, with a top layer (15 cm) exclusively exploited by grasses, an intermediate zone (25–35 cm) utilised by both grass and tree seedling roots and deeper subsoil exclusively tapped by tree seedling roots. Our results are consistent with Walter's hypothesis, but we distinguished between three rather than two layers of tree and grass root interactions in acquiring soil moisture
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    A CFD study of wind patterns over a desert dune and the effect on seed dispersion
    (Springer Netherlands, 2012) Joubert, Eugene C.; Harms, Thomas M.; Muller, Annethea A.; Hipondoka, Martin; Henschel, Joe R.
    In the Namib Desert seed distribution is greatly influenced by wind patterns. Existing literature regarding wind patterns over dunes focuses on two-dimensional simulations of flow over simplified dune structures. The three-dimensional geometries of the sand dunes suggests far more complex flow features exist, which are not captured by two-dimensional simulations. Computational fluid dynamics (CFD) was used to reproduce the three-dimensional near surface wind patterns around a dune with the aim to learn more about seed distribution. Field work included terrain mapping, wind speed, direction and temperature metering. The CFD results show the expected two-dimensional flow features of high pressure at the dune toe, low pressure at the crest and flow acceleration up windward slope. Also observed are some three-dimensional flow features such as a spiral vortex near the crest and transverse flow due to crest-line curvature of the dune. It was also observed how the wall shear stress differs due to the three-dimensional shape of the dune. The wall shear stress suggests that seed accumulation is more likely to occur behind trailing (down-wind) crest edges. Particle tracking showed how seeds tend to move over the dune crest and recirculate towards the crest on the lee-side. The study showed that adding the third dimension makes the simulations more complex, adds to computational requirements and increases simulation time but also provides vital flow information which is not possible with two-dimensional simulations.
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    Sand-ridge dynamics and the evolution of the Etosha Pan, Namibia
    (2012) Hipondoka, Martin; Mauz, B.; Packman, S.; Bloemendal, J.; Kempf, Jurgen; Chiverrell, R.C.
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    Etosha Pan: Dust source characteristics and emission controls
    (Southern African Association of Geomorphologists, 2012) Bryant, R.G.; Eckardt, F.G.; Vickery, K.; Hipondoka, Martin; Murray, J.E.; Abrahams, D.