By Madeline Goddard
Flying out from Darwin is a wonderful thing when you study mangroves, the dense muddy forests you are used to trudging through become an intricate pattern, perfectly balanced between the land and sea. The tidally dictated zonation appears and you can see the vast extent of the 20 000ha Darwin Harbour mangrove estate, home to some 37 species of mangrove. That is of course when you are not flying in the wet season, into a storm. Rain pelted the shaking plane as we entered the clouds, erasing any chance of a view, and I ended up wishing I were back in the relative stability of the mangroves. I am not a fan of flying, however it was worth it to attend the 2nd Australian Mangrove and Saltmarsh Conference, held at the University of Wollongong. “Working with Mangroves and Saltmarsh for Sustainable outcomes” was the theme of the three day conference that brought together over 80 researchers, consultants and land managers who work in our coastal wetlands across Australia and internationally.
Opening the conference was a keynote address from Dr. Bruce Thom who set the scene of the meeting with a personal history of a life dedicated to research of mangroves and highlighted some key shifts in understanding of the mangroves. The eminent Karen McKee also gave a keynote presentation on the wide variety of communication tools currently available to researchers for better communicating research (here’s a hot tip for the next time you give a poster presentation - put a QR code on it with a link to a video or other description of the research).
The program was packed with many aspects of the mangrove and saltmarsh environment; from hydrology, sedimentation, wetland evolution and climate change to restoration, policy and management. Mangroves have long been known for providing crucial habitat for many marine species and for providing protection from coastal erosions and storm surges. More recently they have been identified as some of the most productive ecosystems on the planet and sink large quantities of carbon in below ground stores. There were many stories of mangrove and saltmarsh restoration, successfully returning degraded coastal areas to the fish nurseries, migratory bird foraging habitat, sediment traps and carbon sinks.
Many presentations highlighted the unique location of coastal wetlands that has often left them in a rift between marine and terrestrial managers and scientists. A more pertinent consequence of their situation is they are on the front line of sea level rise. Mangroves have for the last 6 000 years kept pace with sea level rise of a few millimetres per year. They do so by building land, a controversial idea initially, however one now widely accepted and evidence based, and many delegates including Karen McKee have contributed significantly to this area. Elevated sea level rise is a massive threat to our valuable and vulnerable coastal wetlands. The question for many researchers now is will our vital coastal wetlands “sink” as the sea level rises or will they be able to “swim” and build land in pace with the rise?
Surface elevation changes and associated carbon burial in the mangroves of the Darwin Harbour is the topic of my research. Darwin is an interesting place to study mangroves, they are exposed to massive 8meter tides and an average 1727.2mm of rain falls during the wet season. They are also it experiencing some of the highest rates of sea level rise in the world. Determining the current and historical rates of vertical elevation change is critical to understand the response of our mangrove forest. Being able to present some of my preliminary findings of my research was an enriching experience; I gained a lot from the wealth of knowledge by engaging with experts in the field.
Kerrylee Rogers (left) and myself (right) with my poster presentation entitled “Surface elevation in the mangroves of Darwin Harbour”
On the third day of the conference delegates were led on a field trip to Lake Illawarra and the Shoalhaven River. It was a great chance to see the geography of the areas featured in many of the presentations and the cruise down the Shoalhaven River showed a great example of mangrove restoration.
The Shoalhaven River, backed by agricultural land, with some small mangroves (above) and mangrove restoration site with casuarina behind the mangroves (below).
I was fortunate to have the opportunity as an honours student to present my research at the conference, as well as meet in person researchers who I had previously only known through journal articles. I found the experience very inspiring and I would like to thank the Research Institute of Environment and Livelihoods for providing support. I would also like to thank Dr. Kerrylee Rogers for doing a wonderful job of organising the conference and for her support and interest in my research. I am pleased to say that Charles Darwin University will be hosting the AMSN conference in 2016 and I hope all our interstate colleagues get to enjoy the view as they land in Darwin.
Find out more information about the project here