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Nesongano, Wellencia Ndatipo, Simon K. 2026-06-24T10:28:39Z 2026-06-24T10:28:39Z 2025 http://hdl.handle.net/11070/4270 A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science in Environmental Science Land 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 specific en University of Namibia Land degradation Ecological restoration Vegetation establishment Organic mulch Leaf litter Straw Kunene Region Namibia University of Namibia 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 Thesisopen.access