“I always admired Mother Theresa’s compassion and commitment to helping people,” says PhD graduate Linda Luvuno. “I dreamed of becoming a nurse so that I could do just that.”

Growing up in eMpophomeni in Howick, Luvuno loved the grasslands. When she began to realise the impact of alien invasive species, it saddened her deeply.

“I grew up in a rural township where grass is pretty much life. We use it for all manner of things and so the impacts of woody encroachment could be devastating to communities. I realised that I didn’t need to be a nurse to practically help people. In fact, contributing to a better society could take many forms and I see my research as one such way of doing so.”

Dr Luvuno’s research was a collaboration between the Centre for Complex Systems in Transition and the Department of Conservation Ecology & Entomology both at the University of Stellenbosch.

In her thesis, titled Understanding social-ecological regime shifts: the case of woody encroachment in South Africa Luvuno builds on the ecological literature on encroachment to present a broader social-ecological understanding of woody encroachment. Humanity has been very successful in modifying the planet to meet the demands of a rapidly growing human population. As human activities have grown in magnitude, they have become increasingly interlinked with ecosystem dynamics, creating social-ecological systems. Increased human impacts on ecosystems are also leading to an increased occurrence of regime shifts: large, persistent changes in the structure and function of ecosystems and social-ecological systems that often have substantive impacts on the suite of ecosystem services provided by these systems, and on the well-being of people who live in them. As global changes accelerate, better understanding the drivers, impacts and risks of regime shifts has become a key need.

This knowledge has important implications for the formulation of management strategies that aim to either maintain existing desirable regimes, restore previous regimes where a regime shift has occurred, or facilitate transformation to new regimes in the novel planetary conditions we face.

A prevalent regime shift in savannas worldwide, and certainly in Luvuno’s home province of KwaZulu Natal, is woody encroachment. Woody encroachment is a shift from a grassy savanna to a persistently woody savanna, and has direct implications for a variety of ecosystem services such as livestock grazing, and people’s livelihoods that depend on these services. Much of the historical work on woody encroachment has focused on the direct drivers of the process, such as the role of fire or grazing in inhibiting or promoting encroachment. However, less is understood about how underlying social processes may impact these drivers, how ecological changes may feedback to affect some of these underlying social processes, how to monitor woody encroachment as a regime shift and how encroachment impacts ecosystem services and human well-being.

“A real highlight of my research was spending time back in Zululand interviewing community members and game reserve staff about woody encroachment. Living in the Cape for so many years, I’d forgotten how friendly Zulu people are and how much I missed grass! It’s seems so silly but the landscapes we grow up in can be attached to our identity. Being there was cathartic.”

Dr Luvuno hopes that her research will inform policy and management practices, emphasising the importance of understanding the social and ecological interactions that underlie woody encroachment.