Dr Nonkululeko Dladla, a developmental lecturer in Geological Sciences at UKZN focused her PhD study on the stratigraphy and geological evolution of three coastal waterbodies along the north-eastern KwaZulu-Natal coastline to gain an understanding of how coastlines responded to a rise in sea levels in the past and better understand the potential consequences of future changes.
Concentrating on Lake St Lucia, the Richards Bay Harbour and the Kosi Bay system, Dladla looked beneath the ocean’s surface at the complex network of ancient river valleys that underlie these systems, which were flooded during the Holocene epoch as sea levels rose due to melting glaciers.
Despite each of these waterbodies being situated in a similar climatic, geomorphological, oceanographic and sea-level framework, Dladla pointed out that each differs in terms of its palaeo-sediment supply and underlying geological framework. She set out to understand how much these factors influenced the stratigraphic evolution of incised valleys as they evolved from rivers through to estuaries with rising sea levels, and what role they could play in the final geomorphological form. That final form is critical in understanding how estuaries function today, an important consideration as they act as nurseries for juvenile fish species and are current focal points for development around the world.
With the threat posed by climate change and global warming a major current issue, there has been an increased focus on the effect of sea-level changes on global coastlines, both in the present and historically.
‘Reconstructing the geological signatures of these kinds of coastal systems can greatly improve our understanding of how coastlines respond to climate change and sea-level rise and improve prediction of the consequences of future changes,’ said Dladla.
Having loved the subject of Geography while in school, ending up in geology was a happy accident for Dladla. While she thought that the two subjects were similar, she said she had the shock of her life when she arrived at her undergraduate lectures. However, by the end of her first year, the subject had grown on her to the point that she was already planning her path to a PhD.
With UKZN being the only Institution in Africa specialising in Marine Geology, it was the clear choice for Dladla’s postgraduate studies and is where she has developed her research interests in sedimentology and marine geology. Her passion for the subject has also been encouraged by her honours, masters and PhD supervisor Professor Andrew Green.
‘UKZN is my home, and home is where the heart is,’ said Dladla.
Attaining her PhD was not without its challenges – Dladla had to find ways to strike a balance between her work and studies, but motivation from her supervisor, proper planning and dedication helped her find her rhythm and momentum.
The COVID-19 pandemic also took its toll – Dladla lost loved ones to the virus and the emotional cost was high. However, with encouragement and support from her colleagues and community, she was able to persevere to complete her studies.
She published several articles emanating from her studies in the foremost international, peer-reviewed journals, and her PhD was awarded with no corrections to her thesis.
‘I am especially proud of Nku, she is the first South African Black female to graduate with a PhD in Marine Geology, not to mention that the quality of her PhD was outstanding. She is an absolute role model for our students who need mentors they can identify with,’ said Green.
Driven to build a career in marine geoscience research, she completed her PhD while working in her Discipline as a developmental lecturer and will continue working as a lecturer with the completion of her studies.
Dladla expressed gratitude to Green for his inspiration and guidance, and thanked her parents, siblings and niece for their love and support. She also thanked her partner for being by her side, and her friends and colleagues for their encouragement.
Words: Christine Cuenod
Photograph: Sandile Ndlovu