The Council for Scientific and Industrial Research (CSIR) researchers on Tuesday deployed a buoy equipped with a series of instruments in the Theewaterskloof Dam to gain deeper insights into microalgae biodiversity and its significance in supporting the ecosystem health of South Africa’s drinking water dams.
The research team will employ a combination of satellite data and in-water physical and chemical measurements to assess microalgal diversity in near real-time.
This approach will also enable the early detection of potential overgrowth of toxic algal species, which can negatively impact water quality and ecosystem stability, the CSIR said.
The deployment and the data collected will form part of the BioSCape research project, an international collaborative research project built on deep scientific engagement between South Africa and the US. BioSCape is funded by the US government through the National Aeronautics and Space Administration (NASA), the South African government through the New Earth Observation Frontiers via the South African National Space Agency and the National Research Foundation, the South African Environmental Observation Network and the United Nations Educational, Scientific and Cultural Organization.
The BioSCape project employs a combination of remote sensing and field data to gain insights into the distribution, functionality and significance of biodiversity within the Greater Cape Floristic Region, recognised as one of the world’s 36 biodiversity hotspots.
“The growth and diversity of algae are closely linked to the prevailing light conditions in their environment, and the instruments aboard the buoy are equipped to make precise measurements of the underwater light field together with algal growth parameters. Currently, Theewaterskloof Dam is experiencing a significant sediment load due to the recent floods in the area. The dam is typically regarded as seasonally eutrophic with algal blooms occurring during the summer months,” the CSIR said.
Over the next three months, the anchored buoy, dubbed “Gizmo”, will be stationed in the dam, receiving regular visits for maintenance and upkeep.
It is believed to be the only buoy in Africa that houses a hyperspectral underwater optical measurement system.
The CSIR-developed buoy has previously been deployed on South Africa’s western and southern Cape coasts for harmful algal bloom research.
“We have been updating the technology over the years to prepare for this moment to deploy the buoy in Theewaterskloof Dam in support of the high-quality data validation and vicarious calibration objectives of the BioSCape campaign,” said CSIR senior researcher, Dr Marie Smith.
From February to April 2024, the buoy will have a second deployment in Walker Bay for studies on similar water quality aspects. This is mainly in support of the aquaculture industry, which has suffered major financial losses over the years with toxic algae having become a huge threat to production.
In the coming weeks, the CSIR team will also be working with the NASA team members doing fieldwork from the mid October until the end of November at some of the BioSCape target sites, including Zeekoevlei, Rietvlei, Klein Rivier Estuary, Voelvlei Dam and Steenbras Dam.