3 . The sea could be the food bowl of the future. In Jervis Bay, south of Sydney, seaweed, which is rich in fibre and omega 3, is grown and harvested.

Pia Winberg is a marine scientist who runs Australia's first food-grade fanned seaweed company. Her crop is grown alongside mussels (贻贝)and is used as an additive in pasta (意大利面)and other products.

Seaweed is also raised in large tanks, where it absorbs carbon dioxide waste from a wheat processing factory. The business is small, but could help to reduce the ecological footprint of traditional farming.

“We used ten percent of seaweed instead of wheat in breads and pastas, we've eliminated a million hectares of land, we've eliminated all of the carbon dioxide emissions associated with that, and we've also reduced the pressures on very precious fresh water.” said Pia Winberg.

Spiny sea urchins (多刺海胆虫)are another blue economy resource. They can destroy marine habitats, but a recent competition for environmental start-ups in Australia, saw them not as a pest but a delicacy (美味).

Martina Doblin, CEO of Sydney Institute of Marine Science, said, “By 2050 we will have some ten billion people on the planet, and about half the food they eat will come from the ocean. So, we really do need to pay attention to the way that we manage the blue economy-generating wealth from the ocean but in a sustainable (可持续的)way.”

Farming at sea has its challenges. Infrastructure (基础设施)has to be sound, as do supply chains and biosecurity. But get these things right, and the ocean might just be the next great economic frontier.