Every year at our institute’s annual retreat, we present an award for best staff and student publications. Here are the nominations, as selected by a panel of our Emeritus Professors, for 2016. Each nominee presented their work before the awards were announced.
Congratulations to Dr Guillermo Diaz-Pulido who received the staff award, and Peter Rose and Jack Coates-Marnane who jointly recieved the student award.
Strategies of dissolved inorganic carbon use in macro-algae across a gradient of terrestrial influence
Dr. Guillermo Diaz-Pulido, published in Coral Reefs
Dr. Diaz-Pulido’s research is revealing how coral reefs may recover, or not, from algal blooms in the future. He studied how algae that grow on reefs use different mechanisms to obtain carbon dioxide.
Algae use dissolved carbon, including Carbon Dioxide, to grow. There is concern that with increasing carbon dioxide in the atmosphere and ocean, algae may grow faster and outcompete corals. As carbon dioxide in the ocean increases, algae may become more efficient at processing carbon so algae grow faster.
Guillermo found that red algae prefer passive mechanisms, green algae tend to use active mechanisms and brown algae use a mix. Importantly the mix of mechanisms the algae used depended on river run-off and depth.
So the type of algae that grows on coral reefs may change in the future.
Inundation of saline supra-tidal mudflats provides an important source of carbon and nutrients in an aquatic system
Professor Michele Burford published in Marine Ecology Progress Series
Professor Burford is studying one of Australia’s least understood ecosystems – mud-flats. She discovered that the mud flats in the Gulf of Carpentaria can be a very important source of production (that is algal food for animals) for marine ecosystems.
Mud-flats undergo extreme seasonal changes, with drying over the dry season and flooding in the wet season. She used localised experiments and measurements to calculate production in small areas. However, their extent is so huge that it is difficult to scale up these measurements to estimate total production.
Michele and her team used satellite images to calculate extent and duration of flooding. This let them scale-up their local measurements to the scale of the entire system. It turned out that the scale of flooding was the primary determinant of production year to year. Further, in the years where flooding was extensive, the mud-flats were important part of production for marine ecosystems.
Michele was thus able to show for the first time that these humble mud-flats are a critical part of northern ecosystems.
Vegetation resilience to mega-droughts along a tropical floodplain gradient of the southern Murray-Darling Basin
Dr. Sam Capon Published in Journal of Vegetation Science
Vegetation that grows on flood plains can be very resilient to drought. Mega-droughts are droughts that last longer than 10 years. The vegetation can recover its greenery very quickly once rains return.
Dr Sam Capon was concerned about how grazing and cropping may affect the ability of floodplain plants to recover from droughts.
She measured plants, and their seed-banks, across a floodplain that had experienced a lengthy drought. Importantly, not all plants had a seed-bank, so relied on persistence of local individuals to maintain their populations.
Thus, these plants may be particularly susceptible to grazing, which may remove them so they cannot recover after floods.
Sam’s research suggests we need to protect wetlands from cropping and grazing during droughts, so they can recover when rains return.
Daniel Borombovits published in Radiation Measurements
Sand is a critical part of keeping time with an hour glass, but did you know you can age the sand itself?
Dan is using the optics astronomers use to measure the light coming from stars to calculate the age of grains of sand. Optical measurements allow him determine when the sand was eroded from rock.
It turns out the quartz crystals in sand emit different colours of light that vary across their age. Dan has developed optical methods to give much higher accuracy measurements than in the past.
This gives us a new tool for triangulating the age of soils and sediments with other methods. Doing so is an important part of figuring out where and when erosion occurs.
Jack Coates-Marnane, published in Estuarine and Coastal Shelf Science
Jack is revealing how logging of trees around Brisbane is causing Moreton Bay to fill up with mud (he has written about this work earlier on our blog).
He took cores of sediment and used carbon dating to age the different layers of sediment. This let him calculate the rate that the bay has been filling up with mud.
What he found was concerning. There used to be deep holes in Moreton Bay, but now these are filled with mud. So the next big flood will likely cause these holes to spill-over, literally filling up the bay with mud. The bay will likely get shallower and murkier as a result.
However, if we can plant trees along streams and prevent erosion, we have a chance of keeping the bay clean into the future.
Incorporating species losses and gains into a fish-based index for stream bioassessment increases the detection of anthropogenic disturbances
Peter Rose, published in Ecological Indicators
We need to know baselines for fish, so we can target management actions and measure the success of restoration. But often it is difficult to find ‘reference sites’ that are unaffected by human activities. Peter Rose is developing models that can predict what types of fish we should expect in unaffected stream ecosystems.
Peter collected data from across South-East Queensland and Northern New South Wales on fish communities. This included a range of human disturbances, including some reference sites.
Using this data he was able to build models that use fish communities to indicate the extent of human influence. His new method was much more sensitive to gradients of human disturbance than past methods.
Thus, it can help us to measure the health of Queensland’s streams and inform on their management.