ResearchSpace :: Browsing by Author "Naidoo, Sasha"

Browsing by Author "Naidoo, Sasha"

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Adaptation and mitigation: synergies and trade-offs
(CSIR, 2017-10) Thambiran, Tirusha; Naidoo, Sasha
Typically, mitigation and adaptation research has been developed separately, with the mitigation research community focused on taking a global approach to limiting cumulative greenhouse gas (GHG) emissions. The adaptation research community, however, emphasises locally-focused analysis aimed at minimising the impacts of climate change, especially within the most vulnerable communities. International climate policy has historically developed with a focus on mitigation, though in recent years increased attention has been placed on adaptation. For example, at the 21st Conference of the Parties (COP-21) to the UN Framework Convention on Climate Change, countries also committed toward adaptation responses within their Nationally Determined Contributions.
Commentary on the contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change
(2022-09) Naidoo, Sasha
The Working Group III (WGIII) contribution to the 2022 IPCC Report (AR6) provides an updated global assessment of the climate change mitigation process in terms of developments in emission reduction and mitigation efforts, and an assessment of the impact of national climate pledges in relation to long-term emissions goals. New additions are chapters on the social aspects of mitigation and on innovation, technology development and transfer. One of the key messages of the Report is that accelerated and equitable climate action in climate change mitigation and adaptation is critical to sustainable development, with synergies and trade-offs between the SDGs and mitigation and adaptation options highlighted, making connections with the AR6 WGII report. A well-resourced just transition is core to shifting South Africa’s development pathway to increased sustainability, and fostering climate-resilience and low GHG emissions.
Commercial forestry
(CSIR, 2017-10) Naidoo, Sasha
Forests in southern Africa are critically important for sustainable livelihoods and ecosystems but are vulnerable to changes in climate, most important being accumulated temperature and moisture deficit, as well as to other external stressors, such as deforestation, with which climate may interact. Forest resources in the SADC14 region are extensive and diverse. The total forest cover is estimated at 400 million hectares (ha) 15 in area, or more than 40 percent of the total land area of the 15 SADC member states. Forest cover is concentrated in a few countries in the SADC region. The Democratic Republic of Congo, Angola, Zambia and Mozambique have the largest forest areas and account for close to three-quarters of the total forest area in the SADC region. Those four countries are among the five most forested countries in Africa; together with Sudan, they contain more than 55 percent of the continent’s forest estate.
Effect of moisture availability on wood density and vessel characteristics of Eucalyptus grandis in the warm temperate region of South Africa
(2006-09) Naidoo, Sasha; Zbonak, A; Ahmed, F
Productivity of forest plantations in South Africa is highly dependant on soil moisture availability. Soil moisture availability is often limited and evaporative demand is high. Eucalyptus grandis, planted extensively in South Africa, is highly intolerant of adverse conditions, and performs poorly when planted on shallow soils and/or on dry sites. A study was conducted to assess the effect of moisture availability on the wood density and vessel characteristics of E. grandis grown in the warm temperate regions of South Africa. Gamma-ray densitometry and image analysis techniques were used. This study compared cores taken at breast height from compartments representing varying levels of moisture availability. Different levels of moisture availability were achieved using combinations of mean annual precipitation (MAP) and estimated soil water storage (SWS). Preliminary results indicated a strong relationship between MAP and mean vessel percentage. Significant negative correlations were found between site index (SI) and other properties: mean density, mean vessel frequency, mean vessel percentage. Mean wood density, in some instances, showed a trend of decline with increasing water availability. Vessel frequency declined significantly with MAP at medium and high SWS levels. Relationships between water availability and wood properties are expected to become clearer and more robust as the study progresses. Eucalyptus grandis, moisture availability, wood density, vessel diameter, vessel frequency, vessel percentage.
Environmental challenges to meeting sustainable development goals in Southern Africa
(Springer, 2024-01) Mutanga, Shingirirai S; Skhosana, Felix; Mateyisi, Mohau; Thenga, Humbelani F; Naidoo, Sasha; Ramoelo, A; Nangombe, Shingirai S; Lumsden, Trevor G; Von Maltitz, GP; Midgley, GF; Veitch, J; Brümmer, C; Rötte, RP; Viehberg, FA; Veste, M
There is an inextricable link between ecosystem integrity and the potential for achieving sustainable development goals (SDG). This chapter highlights key ecosystem threats and their drivers within the southern African regional context to emphasize the role of earth system science in supporting the achievement of regional sustainable development goals. It describes how some major anthropogenic threats have unfolded in terrestrial, aquatic and marine ecosystems of the region. Earth system science is increasingly contributing to understanding how globally driven climate and environmental changes threaten these ecosystems, and in turn how these impact people’s livelihoods. Long-term changes in rainfall variability, concomitant disruption of hydrological balances, impacts on ocean chemistry, together with more immediate impacts on the frequency and magnitude of extreme climate events are some of the critical global change drivers. While terrestrial ecosystems are already faced with encroachment by novel species, characterized by the proliferation of both invasive alien and endemic woody species, freshwater and marine ecosystems appear more immediately threatened by more local impacts, such as the accumulation of contaminants. Overall, predicted climate and environmental changes are projected to hamper development trajectories and poverty reduction efforts, and possibly exacerbate adverse impacts on human livelihoods.
Estimation of urban surface temperatures using remote sensing in eThekwini municipality
(Global Change Science Conference, 2016-12) Ellero, M; Naidoo, Sasha; Gebreslasie, M
Urban Heat Islands (UHI’s) are an increasingly common phenomenon within urban areas around the world. These heat islands may lead to a variety of negative effects, such as health impacts on urban inhabitants and disruption of the functioning of surrounding natural environments amongst others. The best method of determining the presence and magnitude of UHI’s is through remote sensor thermal imaging. However, due to differing resolution characteristics, certain remote sensors would be better equipped at determining Land Surface Temperatures (LST’s) and from it inferring UHI’s. The aim of this study was to determine the presence and magnitude of UHI’s across eThekwini municipality using Landsat 8 and MODIS remote sensors for each season over the period of a year. An additional aim included checking the accuracy of these sensors in determining LST’s. MODIS LST products were obtained directly from the EROS data centre (EDC) and converted into degrees Celsius. Landsat 8 images were also obtained from the EDC and LST’s were obtained through an algorithm developed by Stathopoulou and Cartalis, (2007). Accuracy results showed that MODIS had an RMSE of 7.04 °C while Landsat 8 had an RMSE of 2.92 °C. MODIS also had an R2 value of 0.65 while Landsat 8 a R2 value of 0.93. Based on these results, Landsat 8 was considered a more suitable remote sensor to determine LST in the case study area. Differences in temperature between highly urbanised and nonurban areas were around 2 - 6 °C warm, confirming the presence of UHI’s within eThekwini municipality. In other areas, the cooling effects of vegetation could be clearly observed suggesting possible mitigation methods.
Estimation of urban surface temperatures using remote sensing in eThekwini municipality
(2016-12) Ellero, M; Naidoo, Sasha; Gebreslasie, M
Urban Heat Islands (UHI’s) are an increasingly common phenomenon within urban areas around the world. These heat islands may lead to a variety of negative effects, such as health impacts on urban inhabitants and disruption of the functioning of surrounding natural environments amongst others. The best method of determining the presence and magnitude of UHI’s is through remote sensor thermal imaging. However, due to differing resolution characteristics, certain remote sensors would be better equipped at determining Land Surface Temperatures (LST’s) and from it inferring UHI’s. The aim of this study was to determine the presence and magnitude of UHI’s across eThekwini municipality using Landsat 8 and MODIS remote sensors for each season over the period of a year. An additional aim included checking the accuracy of these sensors in determining LST’s. MODIS LST products were obtained directly from the EROS data centre (EDC) and converted into degrees Celsius. Landsat 8 images were also obtained from the EDC and LST’s were obtained through an algorithm developed by Stathopoulou and Cartalis, (2007). Accuracy results showed that MODIS had an RMSE of 7.04 °C while Landsat 8 had an RMSE of 2.92 °C. MODIS also had an R2 value of 0.65 while Landsat 8 a R2 value of 0.93. Based on these results, Landsat 8 was considered a more suitable remote sensor to determine LST in the case study area. Differences in temperature between highly urbanised and nonurban areas were around 2 - 6 °C warm, confirming the presence of UHI’s within eThekwini municipality. In other areas, the cooling effects of vegetation could be clearly observed suggesting possible mitigation methods.
Forests, rangelands and climate change in Southern Africa
(Food and Agriculture Organization of the United Nations Rome, 2013-09) Naidoo, Sasha; Davis, C; Archer, Emma RM
This paper provides an analysis of the implications of climate change for forests and rangelands in southern Africa. The extent of the resources and their economic and social functions and drivers of change is outlined. The vulnerability of the resources to climate change and adaptation needs and options for the SADC region are highlighted, as well as potential synergies with mitigation options. A summary of current national actions, country needs and potential areas of collaboration among countries in the region is provided to inform existing and future cooperative initiatives related to the adaptation of forests and rangelands to climate change.
Framework for developing realistic MANET simulations
(2010-04) Burke, Ivan D; Naidoo, Sasha; Olivier, MS
Mobile Ad hoc Networks have become an attractive option for military and disaster-response operations. Its ad hoc nature allows for fast deployment and requires no pre-existing network infrastructure. Most of the MANET protocol development is achieved by means of simulation due to the cost of running real world applications. However, it has become apparent in recent research papers that the simulations of these networks do not adequately reflect reality. In this paper, we aim to investigate some of the assumptions that are made during MANET protocol development and how these assumptions affect the results of these studies. A framework is suggested to help assist future studies to be more attentive to these assumptions. This framework aims at improving the credibility of MANET research for future deployment of MANET systems.
Implementation of water energy food-health nexus in a climate constrained world: A review for South Africa
(2024-03) Mutanga, Shingirirai S; Mantlana, Khanyisa B; Mudavanhu, Shepherd; Muthige, MS; Skhosana, Felix V; Lumsden, Trevor G; Naidoo, Sasha; Thambiran, Tirusha; John, Juanette
In recent years, the Water-Energy-Food (WEF) nexus has gained significant attention in global research. Spatial inequality in water-energy-food security (WEF) and its impact on public health and how this is affected by climate change remains a grand adaptation challenge. South Africa is extremely vulnerable and exposed to the impacts of climate change due to its socio-economic and environmental context. While alternative nexus types have garnered interest, this paper pioneers an extension of the conventional WEF framework to encompass health, giving rise to the Water-Energy-Food-Health (WEF-H) nexus. Despite a plethora of WEF nexus studies focused on South Africa, a substantial knowledge gap persists due to the lack of a comprehensive overview of the enablers and barriers to realizing the WEF-H nexus. South Africa boasts diverse policies related to water, energy, food, and health; however, their alignment remains an ongoing challenge. This study seeks to bridge this critical gap by conducting an exhaustive review of existing literature. Its primary aim is to delve into the intricate mechanisms that either facilitate or impede the actualization of the WEF-H nexus in South Africa. By synthesizing insights from a wide array of literature sources, this research strives to illuminate the challenges and opportunities stemming from the integration of health considerations into the established WEF nexus framework. This exploration holds immense significance, not only for unraveling the multifaceted interactions between these pivotal sectors but also for guiding policy development and decision-making processes in South Africa towards a more holistic and sustainable approach to resource management.
Insights on who funds climate change adaptation research in South Africa
(2025-02) Mantlana, Khanyisa B; Nondlazi, Basanda X; Naidoo, Sasha; Ramoelo, A
Background: This article examines the funding landscape of climate change adaptation research in South Africa to understand the origin, distribution, and thematic prioritization of funding for climate change research in South Africa. Methods: The article used specific search terms to query peer-reviewed publications in the Web of Science and Scopus databases (1985 to 2023). Results: Environmental Science emerged as the most dominant research area during this period, while Agriculture appeared in the top four positions among research areas in climate change adaptation research in South Africa in both databases. The largest number of publications on climate change adaptation research in South Africa is generated through domestic funding, followed by the United States, the United Kingdom, and Germany. The National Research Foundation (NRF) had the highest number of publications. The analysis revealed a strong paucity of funding relationship between South Africa and other African countries in the field of climate change adaptation research. Conclusions: Knowledge of these trends can inform policy decisions on funding of climate change adaptation in South Africa and strategic partnerships between South Africa and the rest of the world.
Market analysis to assess timber products from dryland woodlots and farm forests in South Africa
(Klaus Hess Publishers, 2018-04) du Toit, B; Malherbe, GF; Lambrechts, H; Naidoo, Sasha; Eatwell, Karen A
The growing demand for renewable wood products and competition for land in South Africa will necessitate expansion of planted forests into moderately dry areas. Farm forestry and agroforestry options using species preselected for drought tolerance, water use effi ciency, and pest/pathogen resistance may contribute to a sustainable timber supply. The feasibility of growing dryland farm forestry crops was tested as follows: current input costs and market prices of timber products were obtained in a market survey; growth data from existing dryland experiments were used together with four silvicultural regimes as forest growth model inputs; the yields per forest product class were modelled; and the land expectation values were calculated per regime over a range of site qualities. Projections indicate the best returns where pole markets are available, or where sawtimber plus small-scale poles are produced. With appropriate regime selection, attractive financial returns can be achieved on moderately low site qualities.
Mitigating the UHI: Considerations for Southern African cities
(2016-12) Naidoo, Sasha; Thambiran, Tirusha
Urbanisation in South Africa is expected to increase to 71.3 % in 2030 and reach nearly 80% by 2050, with the City of Johannesburg projected to surpass the 10 million population mark and emerge as a megacity by 2030. Urbanised cities generally have replaced natural land surfaces with materials that retain heat, as well as have waste heat from buildings, motor vehicles and industries. In altering the local environment, this can result in local environmental stresses. Rapid urbanisation coupled with climate change could amongst other issues, increase the local urban heat island (UHI) effect. The UHI, a phenomenon where a temperature difference between the built-up environment and the surrounding (natural) environment exists, is of increasing concern given that more people are moving to cities each year. This contributes to the intensity of the UHI increasing and the number of people affected by it. Limited studies have previously been undertaken to characterise the UHI in African cities, and more recently, studies have been undertaken in Johannesburg, eThekwini (Durban, KwaZulu-Natal), Buffalo City and Nelson Mandela Bay in South Africa. There are still gaps in understanding how these temperatures will change in the future under climate change and greater urbanisation, and how anthropogenic factors could influence the magnitude of the UHI in South African cities. The impacts of the UHI and key interventions, including benefits and unintended consequences of these strategies, were shown. The relevance of the UHI in the context of South African cities was discussed in terms of limited UHI studies and considerations for cooling strategies in cities, as well as the appropriateness of these strategies in terms of planned long-term development goals and climate change.
Mitigating the UHI: Considerations for Southern African cities
(2016-12) Naidoo, Sasha; Thambiran, Tirusha
Urbanisation in South Africa is expected to increase to 71.3 % in 2030 and reach nearly 80% by 2050, with the City of Johannesburg projected to surpass the 10 million population mark and emerge as a megacity by 2030. Urbanised cities generally have replaced natural land surfaces with materials that retain heat, as well as have waste heat from buildings, motor vehicles and industries. In altering the local environment, this can result in local environmental stresses. Rapid urbanisation coupled with climate change could amongst other issues, increase the local urban heat island (UHI) effect. The UHI, a phenomenon where a temperature difference between the built-up environment and the surrounding (natural) environment exists, is of increasing concern given that more people are moving to cities each year. This contributes to the intensity of the UHI increasing and the number of people affected by it. Limited studies have previously been undertaken to characterise the UHI in African cities, and more recently, studies have been undertaken in Johannesburg, eThekwini (Durban, KwaZulu-Natal), Buffalo City and Nelson Mandela Bay in South Africa. There are still gaps in understanding how these temperatures will change in the future under climate change and greater urbanisation, and how anthropogenic factors could influence the magnitude of the UHI in South African cities. The impacts of the UHI and key interventions, including benefits and unintended consequences of these strategies, were shown. The relevance of the UHI in the context of South African cities was discussed in terms of limited UHI studies and considerations for cooling strategies in cities, as well as the appropriateness of these strategies in terms of planned long-term development goals and climate change.
Quantifying and modelling the effects of environmental factors on wood properties of Eucalyptus grandis in South Africa
(University of KwaZulu-Natal, 2011-03) Naidoo, Sasha
This research aimed to quantify and model the effects of specific environmental variables on the wood quality of Eucalyptus grandis in the warm temperate (WT) and sub-tropical (ST) forestry regions in South Africa using nondestructive, rapid screening techniques. Furthermore, because this species lacks distinct annual boundaries that correspond to seasonal climatic changes, the change in wood properties with age usually cannot be studied with reasonable accuracy. For this reason, a study was carried out to examine the linkage between radial variation patterns in wood density and annual radial growth, in order to determine to what degree of accuracy annual ring boundaries could be detected through this method.
A technique to identify annual growth rings in Eucalyptus grandis using annual measurements of diameter at breast height and gamma ray densitometry
(2010-06) Naidoo, Sasha; Ahmed, F; Pammenter, N; Zbonak, A
A technique was developed to identify annual growth rings in E. grandis using a combination of annual measurements of diameter at breast height (DBH) from permanent sample plot (PSP) datasets and bark-pith density profiles. By assessing the pattern of radial variation in wood density within the context of the growth history of a compartment (by means of annual PSP data), it was possible to corroborate the estimation of annual growth rings on density profiles of E. grandis, especially closer to the bark-end.
Unveiling the power duo: Agriculture and social science take center stage in the evolution of climate change adaptation research in South Africa
(2024-12) Nondlazi, Basanda X; Mantlana, Khanyisa B; Naidoo, Sasha; Ramoelo, A
Global changes in climatic conditions threaten the world’s socio-economic development, including South Africa (SA). Climate change adaptation (CCA) research in SA has grown in number (publication rate) and importance (influence on different sectors) over time. A growing body of research uses systematic literature reviews to examine themes within this rapidly evolving field. However, there is still a lack of analysis on the current state of CCA science literature in SA and its evolution over time. This paper fills this gap by providing a cross-validated bibliometric review of scientific literature on CCA in SA using Scopus and Web of Science (WoS) databases. The review is constructed across time, between databases, within databases and on most preferred journals. This transdisciplinary analysis of CCA literature and dominant research themes and priorities spanning 1966–2022 examines how they relate to SA’s adaptation strategy in response to climate change. CCA research has evolved in South Africa. Since 2011/12, publication rates have grown exponentially, averaging between 5% and 26% yearly. Term diversity peaked in 2018 when the publication rate reached 100 publications per year. This exponential development can be explained using themes of clustered terms over time, i.e. biodiversity emerging around 2015/16, Climate & Yield around 2017, and Agriculture & CCA, respectively, in 2018, with 41% similarity between Scopus and Web of Science. Future research needs to advance the monitoring of activities and outcomes on adaptation throughout the thematic evolution period.
Using the Global Stocktake to increase national climate policy ambition and improve implementation: Summary for policy makers
(2022-02) Mantlana, Khanyisa B; Naidoo, Sasha
This report aims to support the independent Global Stocktake (iGST) - the cooperative efforts of a consortium of civil society actors to advance the Global Stocktake (GST), the formal process for periodically assessing collective progress in achieving the long-term goals of the Paris Agreement. The project’s main objectives are to: 1. Investigate how greater climate ambition might play out in five countries selected on the basis of their widely varying circumstances and their importance to achievement of Paris Agreement goals. 2. Obtain insights on ongoing climate change actions at the national level in these countries. 3. Assess national climate action in the context of the GST in the United Nations Framework Convention on Climate Change (UNFCCC). 4. Gain insights into the interplay of national-level climate actions (climate ambition) and international climate politics under the UNFCCC as well as related challenges and opportunities.
Using the Global Stocktake to increase national climate policy ambition and improve implementation: Technical report
(2022-02) Mantlana, Khanyisa B; Naidoo, Sasha
The Paris Agreement, adopted in December 2015, aims to rapidly phase out GHG emissions to attain netzero emissions by the second half of the century, while promoting sustainable development and poverty eradication (UNFCCC 2015). The backbone of the Paris Agreement is nationally determined contributions (NDCs) representing efforts by each country to reduce national emissions and adapt to climate change impacts. Initial NDCs have been submitted by 194 country parties to the Paris Agreement; 13 parties had submitted their second NDCs as of December 22, 2021 (UNFCCC 2021). A key principle of the Paris Agreement is that no country should backslide in its stated NDC targets. That is, each country should ensure that each successive NDC represents an increase in emissions reduction and reflects the party’s highest possible ambition. The manner in which countries implement their NDCs and improve them over time will determine whether the long-term temperature goal of the Paris Agreement is achieved. This situation presents decision-makers at national and international levels with urgent and unprecedented challenges. Climate action, despite accelerating since 2015, falls far short of the unprecedented transformation needed to limit impacts of climate change. In developing countries, the most critical limiters of ambition are access to or availability of finance, political will, and engaged citizens (UNDP and UNFCCC 2019). This report assesses domestic forces that influence climate action at the national level and the ways that they shape international governance of climate change under the UNFCCC, specifically, the Global Stocktake (GST) under the Paris Agreement. The GST is arguably the most innovative outcome of the Paris Agreement. Its overall task is to “take stock of the implementation of this Agreement to assess the collective progress towards achieving the purpose of this Agreement and its long-term goals” (UNFCCC 2015: Article 14.1). It considers mitigation and adaptation, along with their means of implementation and support, in the context of equity and the best available science, and it serves as an ambition-raising mechanism for the Paris Agreement. The first GST began at the end of 2021 and will culminate in 2023. Starting in 2023, the GST will occur every five years in three stages: (1) collection of information, (2) technical assessment of submitted information, and (3) consideration of outputs. The GST will inform NDCs but will not review their adequacy. Nor will it consider whether the temperature goal of the Paris Agreement is adequate or should be changed. The task of the GST is not to redefine the purpose of the agreement, but rather to ascertain whether its implementation is achieving that purpose. Governments alone will not succeed in achieving this purpose—hence the importance of understanding the opportunities for civil society to enhance domestic actions and international cooperation on climate actions. This report describes the approach of the study (Section 2), the relationship between climate ambition and the UNFCCC (Section 3), key barriers to and facilitators of increased ambition (Section 4), and key assessment criteria underlying the analysis of sections 3 and 4 (Section 5). Section 6 presents options, including the independent Global Stocktake (iGST), for civil society to enhance the GST and its outputs. Section 7 links exchanges with the case study countries to international climate change negotiations.
Woodland resources and management in southern Africa
(Klaus Hess Publishers, 2018-04) De Cauwer, V; Knox, N; Kobue-Lekalake, R; Lepetu, JP; Matenanga, O; Naidoo, Sasha; Nott, A; Parduhn, D; Sichone, P; Tshwenyane, S; Yeboah, E; Revermann, R
The countries of southern Africa have an average forest cover of 32% with most forest situated in the tropics. These dry to moist forests are deciduous with a few evergreen species. The open canopy allows enough light to reach the ground to allow the development of a rich grass layer. Generally, these forests are referred to as woodlands. The article gives an overview of the Miombo, Baikiaea and Mopane woodlands of Angola, Zambia, Namibia, and Botswana and focuses on their composition, wood and non-wood resources. Plantation forestry is briefly discussed with most information from South Africa, which has the largest commercial forestry sector in the region. Threats to the southern African woodlands are highlighted, and the current status of woodland monitoring and management is summarised.

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