Developed by indigenous people of what is now Mexico; the chinampa consists of the creation of an artificial island out of lake mud that is eventually held together by the roots of the plants that grow in it as well as their fungal hyphae. This earthen construction is then anchored to the bottom of the lake using the roots of larger plants growing from its structure. These devices were a means for the people of the Mexican valley to be able to grow large amounts of crops on top of Lake Xochimilco and are still in operation today in many cases.
Chinampas are the result of needing to grow an abundance of food on a limited amount of land and access to bodies of nutrient rich water. These soil platforms offer consistent irrigation, access to nutrients and a minimal need for irrigation and fertilizer. Additionally, this technology demonstrates potential to simultaneously solve problems brought on by too many nutrients in the water.
Many bodies of water that are downstream from large farms suffer from eutrophication due to fertilizer run off. These bodies of water grow large amounts of algae and eventually become hypoxic and unable to support other life. The chinampa’s usage of nutrients pulled from the body of water and subsequent feeding of the crops reduces the amount of nutrients available for the algae. Because of this, chinampas have the potential to reduce eutrophication and increase overall ecological productivity. This diversion of nutrients and inhibition of algal blooms make fish and other subsurface life possible.
As these subsurface creatures grow, die and have access to oxygen the overall cycling of nutrients speeds up and that then offers potentially more nutrients that can go towards crops. Then as the crops are harvested and their inedible parts disposed of in the form of ash these nutrients return to the lake and create a closed system of permaculture.
Considering the amount of time and productivity offered by successfully constructed chinampas (estimated 3 harvests a year) for over 1000 years in some cases the initial cost in labor and materials is well justified. The upfront costs of dredging, driving in wooden supports and maintenance until roots systems are established are close to negligible once the volume and duration of returns are accounted for.
Eduardo Longoria – Portunus Co-founder
Scientific researcher, Treasurer of Prophase Biostudios and attendee of the UT Austin for Biology. Eduardo’s focus is on biomanufacturing.