Shedding light on all things green

The Cape Research Centre hall was packed last week as scientists, academics, students and environmental enthusiasts sat spellbound as they listened to Dr Jasper Slingsby.

It may have been the quirky title that drew them: Satellites, sensors, plots, pagodas, frogs, fires and laser beams: developing a biodiversity observation system for Table Mountain National Park.

Dr Slingsby, of Muizenberg said he “suffers” from being interested in almost everything. “I’m often accused of dabbling in too many different projects and lacking focus. Today I’d like to defend myself and outline the method to my madness and grander vision, illustrated with snippets of my research from Table Mountain National Park (TMNP) and beyond,” said Dr Slingsby.

A scientist at the Fynbos Node of the South African Environmental Observation Network (SAEON), based at Kirstenbosch, Dr Slingsby is also a research associate at the Centre for Statistics in Ecology, Environment and Conservation at UCT.

A topic on everyone’s mind at present is the drought and how it is affecting Cape Town, its ecology and its inhabitants.

“The grander vision that we’re working towards with this research is a system that observes environmental change in near real-time, using ground-based sensors linked to satellite remote sensing. This will assist managers, provide data for researchers to observe or predict environmental change, and allow for easier access to information and illustration of the issues for the public,” he says.

The project is centred on observing vegetation regeneration after fire, using satellite imagery. The observed regeneration is compared to the expected vegetation growth for a given environment based on climate or soils. Where the observed signal differs from expectation suggests an environmental impact – faster regeneration occurs where faster growing alien species invade, while slower regeneration or a rapid drop-off would indicate drought mortality, fire or vegetation clearing. These changes are verified using field observations and vegetation surveys.

Dr Slingsby and collaborators have been working on the project for more than five years, gathering crucial baseline data needed to predict the expected vegetation regeneration. They have placed numerous temperature and humidity monitors across TMNP, identifying different micro-climates across the Peninsula. Mean minimum July temperatures range from three to 11.5 degrees Celcius, while mean maximum January temperatures span 17.5 to 32 degrees.

“A major benefit of gathering detailed baseline datasets is that they’re valuable for many other research questions,” says Dr Slingsby.

Some examples of this research explores changes in the flow of fires on the peninsula as the result of urban expansion. It also monitors changes in the distribution and demography of species of special concern.

For example, Rose’s Mountain which is known from only two of 21 historical sites and scientists are trying to find out why.

There is also a focus on charismatic Proteaceae species like the tree pagoda Mimetes fimbriifolius and the Peninsula conebush Leucadendron strobilinum, which have good historical data from the Protea Atlas Project and other studies.

Another project involved collating repeat vegetation survey data for TMNP. This revealed the impacts of climate change and invasive species on fynbos. Dr Slingsby related post fire weather extremes and historical alien species densities to changes in species richness between 1966 to 2010.

“This shows that worse affected sites now had fewer species than before,” says Dr Slingsby.

He adds that while the “grander vision” is not complete, they are not far from it being a reality. “It’s a community project and I can see a lot of
people getting involved. Beyond expanding to include other researchers and research fields, we hope to include citizen scientists to help monitor important species and check sites where the system suggests the vegetation may have been impacted,” he says.

The Department of Science and Technology established SAEON to conduct long-term environmental observation and promote an informed and timely response to global change.

If you would like to become involved, contact Dr Jasper Slingsby at jasper@saeon.ac.za

For information about the Protea Atlas Project, visit www.proteaatlas.org.za/, or other projects, http://dx.doi.org/10.1073/pnas.1619014114