Why do we need aquaponics? Because dirt isn’t "dirt cheap."
Unfortunately, dirt is a resource that we don’t value as much as we should. The root of the problem is that traditional agriculture strips soil of the nutrients it needs to continue providing for terrestrial life and is one of the major contributors to soil degradation. Agriculture fields expose topsoil and cause it to dry out, making it susceptible to erosion by wind and water. The fact is, we’re losing the nutrient-filled topsoil at a much faster faster rate than it can naturally be replaced. According to David Pimental in “Population Growth and the Environment: Planetary Stewardship,” it takes about 500 years to replace 1 inch of topsoil lost to erosion. The minimal soil depth for agricultural production is 150 millimeters (~5.9 inches). From this perspective, productive fertile soil is a nonrenewable, endangered ecosystem.
As a result of soil degradation, crops cannot be grown as fast and more chemical fertilizers are needed to account for this loss in natural efficiency. These agrochemicals can be harmful to people eating the plants grown, as well as the soil it is added to. Chemicals disrupt the delicate balance of microorganisms naturally present in the soil, stimulating the growth of harmful bacteria. The increased costs to mitigate soil degradation mean that good nutrient-rich topsoil is much more valuable than one might think. Dirt isn’t actually "dirt cheap."
One of the underrepresented advantages of using aquaponics over traditional agriculture is that it doesn’t use soil. Plants are able to grow in water that is fertilized by fish waste, rather than in a field with fertilizers, pesticides, and herbicides. In addition to eliminating the need for chemicals, it also makes the need for things like crop rotation that can decrease efficiency and crop yield nonexistent. Many people do not realize that soil degradation is a pressing problem, but as it continues to develop it will start having a major impact on food production.
Fortunately, aquaponics has the potential to be the future of the agriculture industry and is a pioneer of the sustainable agriculture industry, AND it doesn’t use soil. The U.S. is a major crop producing country, and shifting towards more viable means of production and allowing soil to begin its long recovery will have profound benefits.
“Soil Erosion and Degradation | Threats | WWF,” World Wildlife Fund. [Online]. Available: https://www.worldwildlife.org/threats/soil-erosion-and-degradation.
“Soil, Science, and Society: We’re Running out of Dirt - FEW Resources.org.” [Online]. Available: http://www.fewresources.org/soil-science-and-society-were-running-out-of-dirt.html.