South Africa’s unique marine ecosystems are the subject of two Research Chairs that are building important insights and understanding that contribute to the conservation of these important habitats.
The Chair in Marine Ecosystem Research headed by Professor Christopher McQuaid at Rhodes University has two main focus areas.
He explains that the Chair is concerned with building a fundamental understanding of marine ecosystems. Although not directly linked to marine resources, this understanding is critical to their successful management. To this end, the main focus of his current work is building an understanding of coastal ecosystems by investigating the interconnection between marine populations, particularly those that are under threat from over-exploitation. His research group has been studying the impact of over-exploitation on mussel populations along the Transkei coastline, and is fundamental in guiding the design and management of coastal reserves.
The Chair is also developing techniques that help to protect and rehabilitate rocky shores, which are key to the cultivation of healthy ecosystems.
Work around the protection of marine ecosystems has also involved studies of the marine life of the Southern Ocean. In this case, his research has focused on Marion and Prince Edward islands, where he has been studying marine predators that live on land, including seals and penguins.
McQuaid’s second area of research is further offshore, where he is studying the effects of upwelling (a term that refers to the wind-driven motion of dense, cooler, nutrient-rich water towards the surface of the ocean). This research is important to gaining an understanding of how upwelling influences the biodiversity on rocky shores and how it is likely to change in the long term. This is particularly important, because upwelling underpins many of the world’s most important fisheries and is prone to the influences of climate change.
He hopes to extend the scope of his research work to studying the impact of climate change on the country’s marine ecosystems, which are important to the preservation of organisms at the base of the food web and the knock-on effect of their role as food for other marine life.
McQuaid says the Research Chair has had a significant impact on the quality and volume of research that his group has been able to conduct and has resulted in the production of a greater number of postgraduates in this field. Critical recent findings include the key role of crabs in the function and evolution of mangrove ecosystems and a unique example of how biodiversity at the genetic level helps native communities to resist invasive species, while work on the effects of heat-stress on molluscs challenges the prevailing theory and predictions for the effects of climate change.
Professor Renzo Perissinotto at Nelson Mandela Metropolitan University is conducting similar work, although his research group is focused on studying a wider variety of ecosystems and not only those directly linked to the ocean. The Chair in Shallow Water Ecosystems looks at shallow ocean waters from the inner edge of the continental shelf towards the shoreline, into estuaries, coastal lakes and even inland wetlands.
This research is building an understanding of the impact of global change on shallow waters and the organisms that inhabit these waters. This will provide crucial insights into measures that can be introduced to protect ecosystems that are vital to the long-term sustainability of healthy water systems.
His flagship project has been research in the iSimangaliso Wetland Park (previously known as the Greater St Lucia Wetland Park) in KwaZulu-Natal. The significance of this work is partly due to the site having been proclaimed a World Heritage Site for its rich biodiversity and unique ecosystems, but mainly because his research is helping to develop new knowledge to help the rehabilitation and long-term sustainability of Lake St Lucia.
Perissinotto has also begun work to investigate other unique phenomena along the southern coast: living marine stromatolites.
Stromatolites are rocky formations constructed by cyanobacteria (blue-green algae) and constitute “living fossils” that date back more than 3.5-billion years, the most ancient records of life on Earth. He is excited about the opportunity these formations provide researchers in their efforts to build a better understanding of the conditions that prevailed in the primordial ocean and the processes that led to the spread of life from the ocean to freshwater bodies and land masses.
Another area of his research that has potential for significant impact for the country in the coming years is the study of aquatic ecosystems in areas earmarked for shale gas exploration. He says that South Africa would be in a unique position to produce a biodiversity census of these ecosystems prior to their potential disruption by exploration activities. The challenge for other countries that have undertaken shale gas extraction is that they do not have this kind of baseline against which to measure the purported or actual damage to the environment.