Currently, one of the biggest problems the state of California is facing is a shortage of water. The combination of a lack of rainfall, poor conservation practices, and high demand for water by our agrarian economy has nearly depleted reservoirs. Near to my school, the University of California at Santa Barbara, Lake Cachuma has water levels that are drastically low. As you can see in this table, it has lost nearly 6000 acre-feet of water! For readers unfamiliar with this unit of measurement (I included), an acre-foot is equivalent to 325,851.429 Gallons.
Aquaponic systems are recirculating aquaculture systems that incorporate the production of plants without soil. These systems are designed to produce large quantities of fish in small volumes of water. In the process of recycling the water, non-toxic nutrients and organic matter accumulate. These by-products need not be wasted if they are channeled into secondary crops that have economic value or in some way benefit the primary fish production system. If the secondary crops are aquatic or terrestrial plants grown in conjunction with fish, this integrated system is referred to as an aquaponic system. Under the water, fish excrete waste nitrogen through their gills in the form of ammonia, which gets converted to nitrite, and then to nitrate by bacteria. Ammonia and nitrite are toxic to fish, but nitrate is relatively harmless and is the preferred form of nitrogen for fruiting vegetables. 
Aquaponic systems offer many benefits. Plants recycle the dissolved waste nutrients, which reduces environmental waste discharge and conserves water use. Local food production also provides access to healthy foods and enhances the local economy. Moreover, integrated production of fish and plants requires far less land than ponds and gardens. Personally, I can see residential homes having their own units in the future, but not everyone is as optimistic as I am!
Works Cited Diver, Steve, and Lee Rinehart. “Aquaponics – Integration of Hydroponics with Aquaculture.” Ed. Holly Michaels. (2010): 2-5. Print.  Rakocy, James E., Michael P. Masser, and Thomas M. Losordo. “Recirculating Aquaculture Tank Production Systems: Aquaponics – Integrating Fish and Plant Culture.” Southern Regional Aquaculture Center Publication 454 (2006). Print.
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