Prof. Guy Midgley
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Guy Midgley is a researcher in the field of ecology, and has done scientific and policy related work on environmental issues since the 1980s, first with SANBI (1983 to 2014) and since then as a Professor at Stellenbosch University. His main areas of work have been in plant ecophysiology, biogeography and species ranges, population demography and dispersal, and aspects of systems ecology (including disturbance) and global ecology.
He has worked directly on climate change-related issues since 1990. He has collaborated widely with scientists, research groups and NGO’s internationally on global change research, authoring more than 150 publications addressing a wide variety of ecosystems and environmental drivers. He is a globally highly cited researcher, identified as such by Thomson Reuters in 2014. Highly cited work includes that on species extinction risk under climate change, the global role of wildfire in controlling ecosystem structure, and the role of past and future CO2 levels on ecosystem structure and function. He was a co-ordinating lead author for the IPCC 4th, 5th and now 6th assessment report, and for the Global Report of the Intergovernmental Platform for Biodiversity and Ecosystem Services. He chaired of South Africa’s Global Change Science Committee for more than a decade, among many senior national roles. He contributes to international policy processes under the UNFCCC and the CBD. As a research fellow of Conservation International, he co-authored their popular book “A Climate for Life” published in 2008. He currently conducts research into climate and global change impacts on ecosystems and species, working in a wide variety of southern African ecosystems. He is a recent awardee of the Royal Society Marloth Medal for contributions to science and policy, and a Humboldt Foundation Research Awardee for lifetime contributions to science. |
Dr Wendy FodenAssociate Professor, Stellenbosch University
Head, Cape Research Centre, South African National Parks Chair, IUCN Species Survival Commission, Climate Change Specialist Group |
Wendy’s research focuses on climate change vulnerability and adaptation in natural systems. She previously led development of the International Union for the Conservation of Nature (IUCN)’s best-practice guidelines for assessing species’ vulnerability to climate change, as well as of a vulnerability assessment method that has been applied to the world’s birds, amphibians, corals and lemurs. Wendy recently won IUCN’s George Rabb award for innovative conservation and the British Ecological Society’s Marsh award for outstanding climate change research.
Wendy previously initiated and led the IUCN Global Species Programme’s Climate Change Unit, based in Cambridge, UK (2007-2013). She led the South African National Biodiversity Institute's Threatened Species Programme (2003-2007) where she initiated several Red Listing, atlasing and monitoring projects, and founded a scholarship for research on threatened species conservation. Prior to that, as a researcher in SANBI's Climate Change and Biodiversity Group, Wendy studied Namib Desert Quiver Trees and documented some of the first evidence of climate change impacts in arid ecosystems and on plants. In her role as head of the Cape Research Centre at South African National Parks, she leads a committed team of scientists and support staff responsible for conservation research in six national parks and three marine protected areas. She also leads development of the organisation’s Climate Change Preparedness strategy, including development of park-level vulnerability assessments, adaptation planning and ongoing climate change monitoring. Wendy has a great love for wild and remote places, where she can frequently (not) be found. She is a qualified river guide, and has trekked extensively in the Himalayas where she carried out interviews in remote communities to discover their experiences of climate change. |
Dr Nicola Stevens
Research Associate, ECI, Oxford University
Nikki’s research interests are centred around understanding vegetation dynamics in African savannas and how they are likely to change given increasing global change pressures like altered fire and herbivory regimes against a backdrop of changing CO2 concentrations. Along this vein she has become particularly interested in the phenomenon of woody encroachment where open ecosystems across the tropics are being invaded by native woody species. It has also driven her to improve our ability to predict future species ranges under global change by improving our mechanistic understanding of range edges in disturbance limited systems. She is currently based at the Environmental Change Institute at Oxford University but has ongoing projects in Southern Africa with the hopes to expand this research to other tropical savannas.
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Dr Graham von Maltitz
Research Associate
Graham holds a PhD in ecology from the Nelson Mandela Metropolitan University and is a NRF C2 rated scientist. He has over 30 years of experience in environmental and global change, focused on unique problems associated with resource ecology and management in southern Africa, with a special focus on areas of communal land management. He has worked extensively in the savanna, forest and grassland biomes of southern Africa, focusing particularly on natural resource use within the communal areas. More recently he has focused on terrestrial feedbacks to climate processes, land use and land-use change as well as biomass-based energy. He has been involved in a number of global science/policy forums and processes, including links with the United Nations Convention to Combat Desertification and the Intergovernmental science-policy Platform on Biodiversity and Ecosystem Services.
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Caitlin Kelly
Visiting Researcher
As Programme Officer of the IUCN SSC Climate Change Specialist Group, Caitlin helps strengthen a global network of climate researchers working at the science-policy-practice interface to bridge knowledge gaps and improve species conservation in a changing climate. Originally from New Jersey, USA, Caitlin spent four years working for a national conservation nonprofit in Washington, DC, before moving to South Africa where she earned her MSc in Conservation Biology from the University of Cape Town. After graduating, Caitlin worked as a Technical Analyst in the Global Change Biology Lab at Stellenbosch University on a range of projects including the analysis and synthesis of climate change impacts on biodiversity for South Africa’s National Biodiversity Assessment (NBA). As a member of the Africa Regional Assessment Team of the Spatial Planning for Area Conservation in Response to Climate Change (SPARC) project, Caitlin helped evaluate the highest priority conservation areas for strengthening the climate resilience of Africa’s protected area network. She facilitated SPARC workshops for government researchers, policy-makers, and local practitioners across sub-Saharan Africa to improve science-driven policy uptake. Caitlin holds a bachelor’s degree from the University of Virginia and is a graduate of the Emerging Wildlife Conservation Leaders (EWCL) program.
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Mathieu Millan
Visiting Researcher
Mathieu's research interests lie in understanding the mechanisms underlying plant growth forms and how they influence plants performance in different ecological contexts. He joined the GCBG lab to work with Guy, Nikki (University of Oxford), and Sally Archibald (University of the Witswatersrand) on landscape sterility and ontogenetic dead ends in the Lowveld region. His current research focuses on the relationships between tree architecture, developmental stage and flowering ability in common savanna tree species. Mathieu is trying to understand how high disturbance regimes (both in the past and present) influence tree saplings’ ontogeny and architecture and its consequences in terms of population dynamics.
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Dr Heath Beckett
Post Doctoral Researcher
Heath is an ecologist interested in savanna-forest mosaics, extreme fire events (‘firestorms’), vegetation dynamics, pattern formation and the spatial processes involved. He is particularly interested in understanding the enigmatic occurrence of ‘fire-sensitive’ forest vegetation in fire prone landscapes (savannas). His post-doc research focuses on understanding links between plant species and functional diversity and ecosystem function by employing multi-scale monitoring and measurement approaches including Eddy Flux and reflectance sensing technology (e.g. Photochemical Reflectance and Normalized Difference Vegetation Index) at multiple sites across a rainfall gradient in southern Africa.
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Kerry-Anne Grey
Research Assistant
Kerry completed her Honours (2017) and MSc (2018-2019) with Guy and Wendy looking at the ecophysiology of quiver trees (Aloidendron dichotomum) at their southern range edge, both in and out of the field. The findings have furthered our understanding of the potential response of this iconic species to the changing climate in its geographic range. Kerry is now writing up this work for publication. In addition to this she has been collating lines of evidence for a database of observed and projected impacts of climate change on Africa’s biodiversity with Guy, as well as for a database investigating the response of the world's biomes to land-use and climate change with Nikki, both of which are contributing towards the Sixth Assessment Report for the Intergovernmental Panel for Climate Change (IPCC). She has recently started working on the Spaces II ASAP sub-project “Tree-Crop-Animal Interactions".
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Maanda Raselabe
PhD Student
Maanda’s PhD is focused on assessing the overall performance of semi-arid C4 grasses and their potential distribution under changing climate conditions. This will be achieved by measuring their gross primary productivity response to different environmental variables, assessing their eco-physiological responses to different temperature and water regimes, as well using modelling techniques to determine their potential distribution pattens. He aims to determine what the key drivers of primary production in C4 grasses are and how this productivity may change under temperature and water stress. He asks the question, what are some of the main climatic determinants on C4 grass distribution and how may this change in future based on their physiological niches? He will be using Eddy covariance flux towers, ground-based vegetation indices and greenhouse experiments to address these questions.
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Amukelani Maluleke
PhD Student
Amukelani is working on carbon dioxide, water and turbulent energy exchanges between Nama-Karoo and Savanna type vegetation and the atmosphere. His project aims to improve the quantitative understanding of key ecosystem processes to characterise their temporal responses to variations in biophysical inputs (rainfall, temperature, radiation) with the application of the Eddy Covariance flux measurements and remotely-sensed vegetation indices. Linking these two measurement approaches allows the study to improve the spatial coverage of vegetation response assessments of semi-arid ecosystems and ultimately inform decision making about prioritising resource allocation towards climate change resilience in South Africa. He has three flux tower sites: Skukuza and Malopeni in the Kruger National Park; Benfontein in the Free State; and Middleburg in the Eastern Cape.
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Zuzi Nyareli
PhD Student
According to the Millennium Ecosystem Assessment, ecological infrastructure is increasingly being destroyed or transformed around the world, with detrimental implications for human well-being. At the heart of this deterioration is the changing land cover due to unsustainable land-use practices aiming at meeting the economic development needs of the country. Ecological Infrastructure (EI) as specified by the South African National Biodiversity Institute (SANBI) refers to naturally functioning ecosystems that provide valuable services to people, such as water and climate control, soil formation, and disaster risk reduction. Monitoring the long-term impacts of land cover change on the EI can provide a valuable starting point for understanding how the EI facilitates the delivery of ecosystem services over time. Zuzi aims to quantify the impacts of land cover change and climate change in Duiwenhoks catchment, Southern Cape, South Africa, over the past seven decades.
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Felix Skhosana
PhD Student
Woody encroachment is one of the most significant and complex phenomena impacting ecosystem functioning and services in arid and semi-arid savannas and grasslands worldwide. Felix’s project is therefore, looking at the dynamics of woody encroachment and its impact on ecosystem processes and services. It gives a global view on the impacts of woody encroachment on ecosystem services through a systematic review. It then narrows down to mapping woody encroachment hotspots in South Africa using remotely sensed aboveground woody biomass and canopy cover under the theory that areas of high woody encroachment are characterised by low woody biomass and high canopy cover. Due to a growing concern that woody encroachment may result in less water availability for plants and groundwater recharge we then investigate the impact on rainfall partitioning, into throughfall, stemflow and interception across a gradient of encroachment by Terminalia sericea and Dichrostachys cinerea at Wits Rural Facility in the Limpopo Province. Studies done in forests have shown that a significant amount of rainfall is lost through canopy interception, however, there is still a huge gap of such studies in encroached dry systems. He then concludes by upscaling these site-level results in time and space by using the adaptive Dynamic Global Vegetation Model (aDGVM).
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Namita Vanmali
MSc Student
Changing seasonality in the Cape is shifting the optimal growing conditions for Protea and other plant groups within the area. Due to land fragmentation, restricted ranges and limited dispersal, many species may not be able to naturally shift to more environmentally suitable areas, thus putting them at risk of extinction. Namita’s MSc examines the feasibility of using Assisted Colonisation (AC) to reduce extinction risk of Proteaceae in the Western Cape. Modelling tools are used to identify the best candidates for AC by quantifying range shifts and identifying optimal areas for translocation. For ground truth purposes, Protea compacta is used as a case study to test whether SDM suitability predictions across its range are in line with the observed Protea compacta performance. In so doing, she is also investigating the role that microsite choice may play in off-setting site unsuitability.
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Matthew Danckwerts
MSc Student
Matt Danckwerts (our resident pyro-maniac) is working on veld fires in Eastern Cape Montane grasslands. Sourveld livestock farmers in these mountains burn their veld every 3-5 years to remove unpalatable bushes and large tufts of moribund grasses. This is a fairly common management practice in SA aimed at emulating the natural occurrence of wildfires to maintain grasslands and improve grazing potential and quality. Notwithstanding the important ecological role fire plays in shaping and maintaining ecosystems, anthropogenic settlement, accompanied by infrastructural development has resulted in inevitable damage to property when fires occur, often leading to litigation. Legal teams rely on experts in wildland fire behaviour to investigate the origin, cause, and spread of fires to gain a better understanding of potential liability. These investigations are conducted in a post-hoc basis and rely on physical indicators left by the fire, but these indicators have not been empirically evaluated. Matt is testing the reliability and accuracy of these indicators and assessing the feasibility of fire behaviour prediction models to accurately retrodict fire conditions in wildfire investigations.
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Jessie Yuill
MSc Student
Jess aims to use photosynthetic response curve analyses to assess the physiological resilience and potential adaptive response of the seagrass Zostera capensis to changing temperature conditions. This will be achieved by quantifying intertidal photosynthetic responses to key variables (light, temperature and CO2 concentration) in populations of Z. capensis at multiple sites on a temperature gradient across its current distributional range along the coast of South Africa, and under experimental warming conditions. This will produce at least two publications that should contribute to a better understanding of Z. capensis and to support the future restoration and resilience of this species.
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Nosipho Gqaleni
MSc Student
Nosipho is studying the seasonal patterns of rainfall, soil moisture and related ecosystem water use efficiency in a semi-arid Nama Karoo landscape comprised of dwarf C3 shrubs and C4 grasses. Her study focuses on determining whether the soil moisture regime and related vegetation evapotranspiration response in the Eastern-Karoo is driven by rainfall seasonality or by specific rainfall events. She aims to describe the seasonal patterns of ecosystem evapotranspiration and determine the most efficient model to predict evapotranspiration from climatic data She will also be developing a Bucket model for this system to simulate soil moisture patterns at two depths. Her study intends to fill the knowledge gap about soil moisture regimes and ecosystem evapotranspiration in this semi-arid region.
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Tylon Bowman
MSc Student
Tylon is studying the photosynthetic and metabolic performance of two C4 grasses, Digitaria eriantha and Eragostis curvula, representing two extreme ends of an enzymology and likely water use efficiency continuum, under varying drought and temperature conditions. These grasses form part of the ecologically and economically important grasslands of the central plateau of South Africa. He will be harvesting his specimens from a site at Grootfontein Agricultural Development Institute at Middelburg and growing them under semi-controlled greenhouse conditions. His study will allow us to gain a predictive understanding of how these species may respond to warming and drying. This will have important implications for management of these grassland ecosystems as the climate changes in South Africa.
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Christopher Tonkin
MSc Student
Eucalypts are some of the fastest growing and most productive trees. This could potentially make them a viable option for removing CO2 from the atmosphere and helping to mitigate the effects of climate change. However, the basis for their high productivity is not yet well understood but it has been noted that their productivity rates are often limited by drought conditions. Chris’ project is focused on studying the physiological processes of carbon uptake, biomass allocation and water use efficiency between a fast-growing varietal (Eucalyptus grandis x longirostrata) and a drought tolerant varietal (Corymbia henryii x torelliana) of Eucalyptus. He will further explore how temperature increases and drought conditions will affect these physiological processes in a semi-controlled greenhouse study.
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Graduates
PhD
- Dr Claire Davis-Reddy (2018) - Assessing vegetation dynamics in response to climate variability and change across sub-Saharan Africa.
MSc
- Matilda Randle (2019) - Effects of warming on the early establishment of an African savanna tree.
- Kerry-Anne Grey (2019) - Are local range expansions in southerly populations of Aloidendron dichotomum early indicators of a future range shift?
- Amy Edwardes (2018) - The hydrological and ecophysiological effects of simulated climate warming on the soil and vegetation of the Nama Karoo.
- Alta Zietsman (2018) - Response of different plant functional types to environmental variability on Marion Island : Quantifying diurnal patterns over a seasonal cycle by.
Recent Honours
- Kayleigh Murray (2020) - Climatic predictability vs. phylogenetic relatedness: what drives the evolution of seed recalcitrance in South African Oxalis?
- Jayne Rimmell (2020) - Interspecific trait variation of Leucadendron and Protea species along an elevational gradient.
- Jessie Yuill (2019) - Estimating photosynthetic efficiency and primary production of Zostera capensis on an estuarine intertidal gradient.
- Bryn Boden (2019) - Plant biomass responses to experimental warming: A global-scale meta-analysis.
- Natasha Atkinson (2019) - A window into the future of climate change: the response of Agyroderma delaetiito drought in the Knersvlakte.
- Gideon van den Berg (2018) - Linking climate and ocean productivity to the prevalence of southern right whales (Eubalaena australis) in South African waters.
- Lara Brodie (2018) - Looking into the past to predict the future: The case of Aloidendron dichotomum.
- Oliver Hansen (2017) - Natural Adaptors: Insights from estimating changes in African penguin populations since the Last Glacial Maximum.
- Kerry-Anne Grey (2017) - Going south: The changing geographical range of Aloidendron dichotomum (quiver tree) may be explained by ecophysiological constraints at the juvenile stage.
- Matilda Randle (2016) - Comparing the effects of canopy cover increase on grass biomass between Dichrostachys cinerea and Terminalia sericea.