Assessing the link between rural food security and rangeland woody biomass in Limpopo
Date
2017
Authors
Evans, Veronique
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Abstract
People living in rural areas are directly dependent on the local natural resources. The continued unsustainable use of natural resources leads to woodland degradation, through changes in vegetation structure. If the integrity of a rangeland is compromised, then so would the quality and quantity of provision of ecosystem services such as wild fruits, firewood and medicinal plants that rural households rely on. This in turn threatens the food security of rural communities.
Changes in woody biomass and vertical vegetation structure is a consequence of resource extraction in human utilised landscapes. This study aims to enhance the understanding of the role that above ground woody biomass plays in rural South Africa, focusing specifically on the impact that the state of the woody biomass has on surrounding communities’ food security.
The study site was four villages in the Lowveld of Limpopo province: Mafarana, Ga-Selwana, Vyeboom and Ka-Ndengeza. The research assessed woody biomass and vertical vegetation structures, as a proxy for provisioning ecosystem services. I used LiDAR (Light Imaging Detection and Ranging) to measure vegetation structure and estimate biomass in the communal rangelands of these four rural villages. The average rangeland canopy cover and average rangeland biomass of the four case study villages was not influenced by the village settlement areas (size of the village). At the rangeland-scale across the four villages, anthropogenic influences on biomass and vegetation structure were evident. This is particularly true for the biomass in Ka-Ndengeza and Ga-Selwana villages where the spatial trajectory of biomass increased with increasing distance from the village settlement as well as the nearest road. High levels of anthropogenic disturbance were evident in Mafarana’s rangeland, where the biomass gradient was bimodal (had two maximum points), and levels of human disturbance was evident at increased distances from the village settlement and the nearest road.
Having explored the impacts that rural households have on the biomass of their communal rangeland, this study then aimed to explore the cost associated with collecting firewood. The access to fruiting trees was explored as 97-100% of all households were reported to use this resource. Based on the examination of the cost pathways on a finer scale, slope and shrub cover only factor in at the end of a pathway. Moreover, the least cost pathways value is that they show that accessing a resource is not uniform, as multiple factors influence this access. This study found that, the cost to access a natural resource does not increase with increasing distance
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from the village settlement as described in the “Central Place Theory” and Piosphere Theory and that there are multiple factors influencing accessibility. This research highlighted the impact that human utilisation can have on woody resources and vegetation structure in communal rangelands.
After establishing the effect of resource extraction on vegetation structure, the study goes further to explore the links between rangeland integrity and food security. This was done with household interviews that were conducted with the person responsible for household tasks, across the four case study villages in Limpopo, South Africa. The household survey consisted of 28 questions, divided into five categories. The first two sections focused on collecting information regarding the household characteristics, income and expenditure. The following section focused on the use of the suite of local natural resources. The questionnaire also focused on describing the source of the fuelwood used within the household, whether the fuelwood was purchased or collected, species preference as well as perceived declines or increases in fuelwood availability. The questionnaire also explored food security and nutrition, food shortages and the diet of interviewed households.
The most commonly utilised resources were firewood, wild vegetables and wild fruit which were used across all four study villages. This study found that virtually all the households, across all four villages used firewood, wild fruit and wild vegetables. Despite this that some households are clearly more vulnerable to food insecurity than others. Ga-Selwana was the only village that had no households that experienced hunger all the time. Mafarana and Vyboom had the highest proportion of households that did not experience any food shortages in the last year. The results from this study suggest that improved food security might be associated with a healthier state of the communal woodlands, but more detailed analysis of where the relationship exists needs to be explored.
This study found that the resource use and the associated disturbance gradients are settlement specific, which highlights the value of settlement specific studies that incorporate local information is. It is expected that the disturbance gradients evident in this study will begin to diminish and merge around the settlements as the future vegetation structure becomes more homogeneous. The intensive use of nature resources evident in this study suggest impending, if not already occurring, sustainability issues. Repeated data collection is required to assess and monitor the changes in woodland structure and biomass as well as change in patterns of rangeland use as natural resources decrease.
Description
A dissertation submitted in fulfilment of the requirements for the degree of Master of Science to the Faculty of Science, University of the Witwatersrand, Johannesburg, Johannesburg, 2017
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Citation
Evans, Veronique Mary (2017) Assessing the link between rural food security and rangeland woody biomass in Limpopo, University of the Witwatersrand, Johannesburg, https://hdl.handle.net/10539/24835