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Item The governance of indigenous natural products in Namibia: Nature, diversity and dynamics(2018) Ndeinoma, Albertina;Non-Timber Forest Products (NTFPs) are harvested in many countries for subsistence purposes as well as for trade. These products provide a livelihood to households when used for subsistence or sale; they also generate significant revenue for companies and governments. Estimating the value and volume of NTFPs is difficult, both because most NTFPs are used for subsistence purposes and records are therefore lacking, and because products that are traded internationally fall under different product categorisation codes.Item The potential of goat manure as a hydroponic nutrient alternative for tomato production in Namibia(University of Namibia, 2018) Mowa, EdgarHydroponics is a cultivation method of growing plants in water. It is a technology suitable for farming that is under artificially controlled environments but can be adapted to situations where land is a constraint. In Namibia this is a potential method for vegetable cultivation. Hydroponics vegetable production has been demonstrated successfully using a balanced conventional nutrient solution, globally, and therefore, an evaluation of its suitability in Namibia using goat manure solution as a source of organic hydroponic nutrients. An alternative hydroponics nutrient solution has been sought after but often failed due to nitrogen in organic sources being predominantly organic, a form plants cannot access. The study had two stages, the first being a laboratory experiment aimed at formulating a Goat Manure Derived Hydroponic Nutrient Solution (GMDHNS). This involved the determination of source of microorganisms, concentration of microorganisms and amount of goat manure for optimal generation of nitrates from goat manure. Variables measured included nitrate levels generated and levels of other nutrients. The second stage was a field experiment which tested the GMDHNS effect on tomato performance and quality. Variables measured included, plant height, stem diameter, nutrient use efficiency, plant biomass, number of flowers, number of fruits, yield, total soluble solids, and lycopene content. Commercial Hydroponic Nutrient Solution and tap water were used as controls. Locally sourced microorganisms significantly (P< 0.05) transformed organic nitrogen in goat manure into plant available nitrates reaching levels of 198mg/L hence was the basis of the organic hydroponic nutrient solution. Tomato vegetative growth (height, stem diameter and leaves) were significantly (P< 0.05) improved by the formulated GMDHNS compared to growing tomatoes in Tap Water (TW) where no fertiliser was added and that GMDHNS was comparable to using Commercial Hydroponic Nutrient Solution (CHNS) in terms of plant growth. Plant reproduction (flower and fruits) were also significantly (P< 0.05) influenced by the formulated GMDHNS more than by the TW treatment even though yield from GMDHNS was less than that from the CHNS. The quality (lycopene, Total Soluble Solids, fruit size and weight) of fruits produced from plants in the GMDHNS was significantly (P< 0.05) more than that in fruits from the CHNS. Thus, based on the results from this study, it can be concluded that a hydroponic nutrient solution can be formulated from goat manure. Furthermore, it can ii be concluded that the locally formulated hydroponic nutrient solution enhances quality, growth and reproductive performance of tomato, even though it may still need further optimization. Follow-up studies to the present study should be done to further optimise GMDHNS and that artefactual should also follow for practical uptake of these findings.Item Optimizing non-flooded landscape units to support maize production in the Zambezi region, Namibia(University of Namibia, 2017) Mwazi, Fidelis N.Globally, floodplains have experienced floods of different magnitudes at different times. As such the inundations of floodplains affect agricultural activities and such impact is evident. In Namibia, the Zambezi Region has experienced high variability in rainfall patterns, extreme rainfall and flood in space (spatial) and time (temporal) more than any other region as a result of climate variability. The non-flooded landscape units consequently become the only available option for crop farming activities during flooded years. The agronomic productivity status of these non-flooded landscape units in terms of soil and climatic factors as well as their land suitability for maize production in space and time given the prevailing climatic conditions has not been investigated. At the same time our understanding of how small-scale farmers in the region incorporate soil and climate factors into their crop production decisions is limited and affects the provision of extension advice. Yet soil and climatic factors clearly influence land use activities, including rain-fed maize production. The overall objective using maize as a case study crop was to assess possible ways that might optimize the non-flooded landscape units to support arable production in the Zambezi Region. The study was undertaken at both local and regional level using the Kwalala non-flooded landscape unit in the Kabbe North Constituency. Thus, the soil moisture and temperature were measured at various soil depths (20, 40 and 60 cm) between October 2012 and October 2015 using the Decagon data collection system (data loggers and sensors). In addition, secondary climatic and soil data were collected. Hence, Multiple Regression Analysis (model) and the CropWat model (K4 research model) as quantitative methods were used for data analysis. Findings in this study suggests that the observed soil moisture content varied from 9.7 to 33 VWC % loamy sand soils; 7.9 to 26.1 VWC % sandy loamy soils; and 4.9 to 22.9 VWC % sandy soils during the growing period between October and April. At the same time the maize crop water requirements (CWR) and maize water use (ETo) observed for the area ranged from 1.25 to 5.79 mm/day (CWR) and 4.01 to 4.44 mm/day (ETo). Therefore water content sufficiency was significantly (p< 0.05) available to sustain the agronomic crops during the growing period between October and April. Thus these findings implies that the non-flooded landscape units are suitable for rainfed maize production in the context of rainfall, soil type, soil depth, soil temperature, and soil water content sufficiency as well as maize CWR and ETo as long as November is the planting date or 130 days growing period. The incorporation of these findings may mitigate the effects of land conversion by guiding such transformation in an ecologically appropriate direction to ensure sustainable agronomic production, for example, if such non-flooded landscape units are aimed to be used for maize production purposes. It is therefore recommended that further studies on soil moisture induced by the flood be carried out to provide an insight on the soil moisture content driven to top soil surface by flood, since during the period of this study extreme flood did not take place and led to question one of this study not been answered.Item Molecular biogeochemistry of lipids in four natural environments(1978) Boon, J.J.