News & Events
Macro-Micro interactions in marine sediments control the establishment for invasive macrophytes
Speaker(s): A/Prof. Paul Gribben, School of Biological, Earth and Environ Sciences, Centre for Marine Bio-Innovation, University of New South Wales, Australia
When: 24 May 2017 (3:00 - 4:00pm)
Where: SBS CR2 (Level 1)
Type: Seminars


Our inability to manage invasive species stems in part from a lack of understanding of the processes that control their successful establishment and spread. To date, studies have largely considered above-ground processes, but emerging research from terrestrial ecosystems demonstrates that below-ground processes under microbial control can determine the outcome of interactions between native and invasive plants. Whether sediment microbes control native/invasive macrophyte interactions in marine ecosystems is untested. Here I present the results of experiments conducted on two native-invasive macrophyte systems, one in the south eastern Australia and the other in the Mediterranean Sea, each consisting of a complex including an invasive Caulerpa sp. and a native seagrass. Overall, microbial communities between the native and invasive macrophytes differed in a way that relate to functional changes in sulfur cycling between the macrophytes. Moreover, I show that microbes from seagrass habitat reduce the success of Caulerpa fragments, and microbes from Caulerpa habitat positively affect fragment growth. Thus, similar to terrestrial ecosystems, microorganisms may indirectly control the success of invasive macrophytes in marine ecosystems.


Paul is an Australian Research Council Future Fellow and Director of the Sydney Harbour Research Program (Sydney Institute of Marine Science). He did his PhD at the University of Auckland on developing sustainable bivalve fisheries, before moving into the field of community ecology. Paul applies fundamental theory to applied issues, such as understanding how anthropogenic stressors influence habitat-structure and biodiversity, and the spread and impacts of invasive species. Paul melds often disparate fields of ecology to provide a more complete understanding of the processes structuring benthic communities. More recently he has applied this approach to understanding how microbes influence the success of invasive marine macrophytes.