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An agricultural experiment called Nemo's Garden is taking farming to a new level - about 20-feet below the ocean's surface! The endeavor is the brainchild of Italian entrepreneur and scuba diving enthusiast Sergio Gamberini who wanted to combine his passion for diving and farming to create a sustainable food source without disturbing the underwater ecosystem.
He came up with the idea in 2012 while diving in the coastal waters close to his hometown of Noli in Northern Italy. For his design, the visionary drew inspiration from ancient diving bells that were used by divers before the invention of underwater breathing gear. The dome-shaped structures that were suspended by cable worked as both, a transportation device and breathing chamber, thanks to the air pockets trapped inside.
The first greenhouse, manufactured by Gamberini's diving face mask company Ocean Reef Group, was a simple transparent plastic bubble that was fitted with metal struts to keep it from collapsing. It was then transported underwater with a tub that contained basil seeds planted in compost. To the diver's surprise, the plant grew almost twice as fast as it normally would on land. Unfortunately, the plastic biosphere did not fare as well and kept subsiding under the high water pressure.
It took Gamberini and his son Luca, three years to perfect the design, but it was well worth it. Nemo's Garden, which is run in partnership with Italy's Center for Agricultural Experimentation and Assistance of Savona (CERSSA), now boasts seven greenhouses. They range from 50 to 3,000 liters in volume and harbor over 15 crops, including basil, peas, radishes, lettuce, and even strawberries. To take full advantage of the limited space, Gamberini uses Hydroponics, a method of growing plants using mineral nutrient solutions, in water, without soil.
The plants are regularly monitored by sensors as well as human divers who track metrics like the biosphere's pressure, air, surrounding water temperature, PH levels, oxygen, carbon dioxide and humidity.
So how are these plants able to thrive 20-feet underwater? According to the experts at CERSSA it is the stable underwater habitat. The evaporating seawater condenses on the biosphere's inner wall creating almost 85% humidity. Meanwhile, the surrounding seawater keeps the temperature at a steady 77°F. Also helpful is the high concentration of carbon dioxide in the ocean water. Another big plus? There are no predators or pests, allowing the plants to prosper without nets, fences, or pesticides.
The one element that is puzzling some experts is how the plants can grow underwater where sunlight is sketchy at best. While Gamberini's team is still conducting experiments to try determine the reason, they speculate that the higher temperature, humidity and carbon dioxide may be compensating for the lack of light. The diver who plans to publish several papers about his findings is particularly excited about his theory that underwater pressure might be boosting plant growth. "I'm positive that there is an excessive interaction in their cellular membranes because of the pressure," he says.
True to Gamberini's mission, the greenhouses are not harming the underwater ecosystem. In fact, the ocean dwellers seem to be loving Nemo's Garden! Octopuses have been spotted lurking under the frames while endangered seahorses are busy developing nurseries inside the biospheres. What's amazing is that the marine animals are not disturbing the plants.
Due to restrictions from the local government, Nemo's Garden is currently in operation only four months a year - from May to September. While not ideal, it has given the researchers ample time to test their concept and get a taste of the delicious underwater harvest.
Gamberini and his son who are currently showcasing their unusual garden at Expo Milan, eventually hope to create scalable greenhouses that can be used for commercial food production. They believe that the underwater greenhouses will be especially helpful in places close to the coast, where the land is not very hospitable to growing crops. However, for now, fans will have to contend with the 4-inch mini-biospheres that Gamberini plans to give away to donors of his Kickstarter campaign. He hopes that the tiny greenhouses that can be used to grow herbs inside home aquariums may lead to new insights about this exciting new frontier in agriculture.