Masters of Health Magazine January 2017 - Page 69

Hydroponics

(From the Greek words hydro, water and ponos, labor) is a method of growing plants using mineral nutrient solutions, in water, without soil. Terrestrial plants may be grown with their roots in the mineral nutrient solution only or in an inert medium, such as perlite, gravel, mineral wool, or coconut husk. This is one of the ways Marando farms grows vegetables on our farm.

Researchers discovered in the 19th century that plants absorb essential mineral nutrients as inorganic ions in water. In natural conditions, soil acts as a mineral nutrient reservoir but the soil itself is not essential to plant growth. When the mineral nutrients in the soil dissolve in water, plant roots are able to absorb them. When the required mineral nutrients are introduced into a plant's water supply artificially, soil is no longer required for the plant to thrive. Almost any terrestrial plant will grow with hydroponics. Hydroponics is also a standard technique in biology research and teaching.

Aquaponics is a system of agriculture involving the simultaneous cultivation of plants and aquatic animals such as fish in a symbiotic environment. In a traditional aquaculture, animal effluents accumulate in the water, increasing toxicity for the fish. This water is then led to a hydroponic system where the by-products from the aquaculture are filtered out by the plants as vital nutrients, after which the clean water is recirculated back to the animals. The term aquaponics is a portmanteau of the terms aquaculture and hydroponic.

Aquaponic systems vary in size from small indoor or outdoor units to large commercial units. The systems usually contain fresh water, but salt water systems are plausible depending on the type of aquatic animal and vegetation.

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