Andrew D. Irving1, Angela C. Capper1, Emma J. Theobald1, Joana F. Costa2, Emma L. Jackson1
1Coastal Marine Ecosystems Research Centre (CMERC), Central Queensland University. 212 Alf O’Rourke Drive, Gladstone, QLD, 4680, Australia.
2School of BioSciences, University of Melbourne. Biosciences 4, The University of Melbourne, Royal Parade, Parkville, VIC, 3052, Australia.
The capacity of many seaweed species to rapidly absorb soluble nutrients and convert them into primary biomass provides opportunities for their use in the bioremediation of nutrient enriched waters (Gorgula & Connell 2004; Worm & Lotze 2006). Marine-based aquaculture of seaweed has the potential to target diffuse source nutrient discharges, capture carbon and produce valuable bio-products such as fertiliser, soil conditioning agents and agricultural fodder (Roque et al 2019; Mansori et al 2015). Australia boasts an enormous diversity of seaweeds, with over 3,000 species currently recorded, many of which are endemic (Womersley 1987). Such diversity presents benefits for maintaining healthy marine ecosystems, but also a challenge for determining the potential to use native seaweed as a nutrient biofilter, and ultimately, a source of bioproduct. Ideally, species used for biofiltration should grow rapidly to a size where adequate biomass can be obtained, while also being amenable to laboratory-based culturing for subsequent out-planting in identified field locations (i.e. seaweed mariculture). We applied a multi-criteria selection model developed for the purposes of identifying likely candidate seaweed species for biofiltration and bioproduct development; in particular, for fertilizer and agricultural/horticultural use in Queensland’s coastal waters. Species were selected based on their abundance and distribution, habitat-euryhalinity, form and life history traits. From a species database of 1,380 algal species, our selection model resulted in a shortlist of 21 macroalgal species as promising biofilter candidates to improve water quality along the Great Barrier Reef Marine Park (GBRMP) coastline.