Macroalgae to grow on land

South Australian producers could one day be harvesting macroalgae in a multi-million dollar industry from land-based farms – and collecting carbon credits into the bargain
February 25, 2011

Macroalgae to grow on land

SARDI, Flinders University and University of Adelaide scientists are collaborating with Abalone Investment Ltd, Adam & Amos Abalone Foods Pty Ltd, Coorong Aquaculture Pty Ltd, Marinova Pty Ltd, Penrice Soda Products Pty Ltd, PIRSA Fisheries & Aquaculture and Science to Manage Uncertainty to select the best species and explore farming options in a $2.3 million three-year project.

Funding of more than $1.14m has been provided by the Premier’s Science Research Fund, with additional cash and in-kind investment from the partners, and support through Marine Innovation South Australia (MISA).

The project aims to establish South Australia as the national leader in large-scale macroalgal aquaculture, scope potential new products from human food to nutraceuticals and abalone feed, and help local producers capture a slice of the annual $8 billion world wide industry.

Project leaders, Steven Clarke and Dr Sasi Nayar from SARDI, say that Australia annually imports around $15m worth of macroalgae, or seaweed as it is commonly known, and the few commercial enterprises in SA that utilise macroalgae rely entirely on collecting macroalgae cast as drift on beaches.

“The best way for the industry to grow is through aquaculture,” said Mr Clarke. “We will be demonstrating its potential from ‘the producer to the plate,’ developing farming systems for macroalgae, new products and economic models,” he said.

Mr Clarke said the farming systems will provide a proof-of-concept demonstration for the mass culture of macroalgae.

“Land based farming in tanks, raceways and ponds will give farmers more control over the environment in which they are growing their macroalgae, achieve faster growth, easier harvesting, higher quality and more reliable quantities of macroalgae, as well as better management of pests and diseases” said Mr Clarke.

Photo Caption: Project leaders Steve Clarke and Dr Sasi Nayar beside one of six National Collaborative Research Infrastructure Strategy (NCRIS) 20m2 raceway ponds based at SARDI Aquatic Sciences, West Beach, which will be used to test production of macroalgal biomass.

“The cultured macroalgae can also be used to capture wastes such as carbon dioxide and nutrients and turn these into useful resources, adding significant environmental value,” he said.

Macroalgae are used as marine vegetables and are an important food in many Asian countries such as China, Korea and Japan, and market demand is quickly growing in Australia.  Macroalgae are also used to produce high value health food supplements, nutraceuticals and pharmaceuticals, as well as lower value aquafeeds, stock feeds and a wide range of garden fertilisers.

Dr Nayar said South Australia was ideally suited to growing macroalgae.

“SA’s natural advantages for macroalgal aquaculture include an internationally recognised high diversity of species, a conducive climate for high productivity, excellent water quality, and ideal Gulf, bay and land locations for large scale farming,” said Dr Nayar.  “These coupled with favourable government policies and regulatory environment, as well as potentially promising markets, offer SA a unique opportunity to become the national hub of a sustainable macroalgae industry that is clean and green.”

He adds that there is great potential for expanding the macroalgae market.

“The current market for macroalgae for human consumption could pave the way for the development of local species and technologies that enable production to displace current imports and fetch between $20-40 per kg.

“As an abalone feed, a modest 10% replacement of manufactured feed with macroalgae could lead to savings for growers of about $200,000 per annum on a typical farm.

“Some macroalgal species are also a gold mine of chemicals of pharmaceutical interest (bioactives), with about 15,000 having been isolated so far, some worth many thousands of dollars per kilogram”.

Dr Nayar says the project will investigate the potential of the industry from research and development through to the proof-of-concept stage, prior to commercialisation.  Commercial development is likely to occur in coastal areas, although areas affected by inland saline waters may also prove suitable.

“We will be starting laboratory trials soon to understand the physiology of the species of interest sourced from the local environment, then focusing on optimising the culture of these species within select proof-of-concept growing systems,” said Dr Nayar.

“As part of the process we will be developing new products such as macroalgae based manufactured abalone feed, as well as demonstrating with the help of some of our industry partners, that the macroalgae produced can be used for human food and bioactives,” he said.

“A bio-economic model, including government policies involving land and sea-based cultivation systems, translocation of selected species and allocation of farming sites, will be used to summarise the results of the research program and to attract investment to help in the commercialisation of the industry,” he added.

SARDI is also working on a separate seaweed aquaculture project which aims to farm macroalgae in conjunction with sea-based finfish farming to help reduce the environmental footprint of fish farming and develop a secondary industry.