Into the unknown


Gareth Belton returning from a dive on Ningaloo Reef.
Image: Gary Cranitch.

 

3 June 2010
 
"What's out there?"
 
According to Gareth Belton of the University of Adelaide, this is the question that science must answer for conservation efforts to be truly effective.
 
"You can't do conservation if you don't know what you're trying to save," Gareth says.
 
"There are only a million or so species described, but there could be anywhere between 10 and 100 million species in existence that we are yet to discover and describe. For example, we have only explored two per cent of the ocean below 200 metres. We really don't know what's out there," he says.
 
Gareth is working with the University of Adelaide's Dr Fred Gurgel to collect and identify species of macro-algae and seagrass on the CReefs Ningaloo expedition.
 
"On this trip, we are gathering the most basic of data: how many species are there, and how much genetic diversity is there within species from different regions of Australia," Gareth says.
 
This information will help set the baseline knowledge about the Ningaloo Reef marine flora, without which we cannot detect significant changes - if and when they occur. Algal species can be monitored against this baseline over time.
 
Algae are a diverse group, ranging from microscopic forms, such as phytoplankton, to 30 metre-long seaweeds such as the giant kelps found in southern Australia and Tasmania.
 
Algae play various roles in the marine environment. They are major primary producers – producing oxygen, fixing carbon dioxide, and removing nutrients from the oceans. Algae provide refuge and food for fish and invertebrates and on corals reefs they play a vital role in cementing the structures of the reef itself.
 
However, direct human impacts to coastal environments as well as the increase in atmospheric carbon dioxide concentrations which will result in ocean acidification, can have negative effects on algae, especially the calcareous algae.
 
"All the elements within an ecosystem are linked. If the algae go, that will eventually affect everything else in the reef," Gareth says.
 
"So if they go, who knows what will happen?"
 
Samples of the algae Gareth collects on the CReefs Ningaloo expedition will be pressed for herbarium collections, deposited and curated at the SA State Herbarium, and samples will be taken for DNA analysis to better understand the genetic diversity and evolution of marine macro-algae.
 
This knowledge will assist other scientists working in marine research and conservation.