Friday, October 26, 2012

sustainability news: 'Aquaponics' Help Islanders Cultivate Crops and Raise Fish

A pilot aquaponics experiment is now underway in the Cook Islands that has the potential to become the South Pacific region’s best chance for preventing food shortages.

First announced during the Pacific Islands Forum earlier this year (27—31 August), the pilot project combines aquaculture (raising aquatic animals like fish in tanks) and hydroponics (cultivating plants in water) in symbiosis, a strategy that can be replicated in other island nations.

The project’s long-term objective is to give Pacific islanders — who are facing climate-related issues such as drought and fish poisoning — a way to sustainably grow crops using minimal water and no pesticides.

The Cook Islands aquaponics project was the brainchild of Pacific Islands Trade and Invest, the business arm of the Pacific Islands Forum Secretariat, which has teamed up with the New Zealand and Cook Islands governments, and with Lynnsay Rongokea and Barbara Thomson, both from the Cook Islands, to design and implement the project.

Over the past three months, the team has been successfully growing vegetables using aquaponics in a tank-like structure that emulates a natural ecosystem.

The premise of the project is simple: an attendant feeds fish in a tank, which excrete nitrate-rich waste into the water that runs through a mesh filter and irrigates plants.

Those plants filter out by-products, their roots and microbes, removing nitrates to use as vital nutrients. Once the crops have naturally filtered the water, it is aerated and re-circulated back into the fish tank.

The end products are sustainably grown fish and vegetables free from chemical contamination. The system uses just two per cent of the water used up by traditional agriculture and has zero impact on the health of the lagoon.

There is no need to discard or drain water circulating throughout the system and there is no need for chemical fertilisers, pesticides, herbicides, insecticides and fungicides. More