Towards a Sustainable Food System: Principles of Traditional Agriculture as New Values for Commercial Agriculture
By Christina YinPublished March 23, 2016By Christina Yin, 3/23/16
The goal of improving soil and water management techniques was a driving force behind the development of the chinampas in Mexico. Chinampas are a grid-like system of elevated farm plots surrounded by water on at least three sides, and have been known as one of the world's most intensive and productive farming methods since their creation over two thousand years ago. The system produces several crop cycles each year, and the constant flow of water allows the chinampas to remain fertile for centuries without having to lie fallow. The Aztecs inhabited a valley in central Mexico that would flood each year during the rainy season, so they took advantage of this natural flow of water from nearby streams in the creation of the chinampas. They drained the flooded plains and redirected the water to flow freely into Lake Xochimilco and Lake Texcoco, reinforcing the canals they created by digging up mud and constructing elevated farm plots. The Aztecs reclaimed the natural flooded plains for agricultural use, but they ensured that the land remained healthy and fertile through organic means: they composted by spreading thick layers of mud and manure over the seeds in each plot, and using living willow trees and duckweed to hold the sides of the gardens together. The chinampas allowed the Aztecs not only to devise a management system that reclaimed the swampy terrain for agriculture, but also to maintain this system through cooperation with the natural environment and promote long-term sustainability that has persisted for over two thousand years.
In China, another challenging physical terrain has driven indigenous populations to develop new methods of managing water and soil properties. The Hani people of the mountainous region of Yunnan, China have adopted another traditional farming technique: the cultivation of rice terraces. The terraces are made of flat, step-like increments that continue all the way up and down the mountainside. A huge benefit is that they provide an effective irrigation system the harsh growing environment: canals and aqueducts direct water through all levels of the terraces, avoiding soil erosion and runoff. The flat surfaces at each level allow for water to absorb into the dry soil, and prevent the possibility of erosion through streams of water flowing uncontrolled down the sides of the mountains. They also ensure that nutrients will flow to the lower levels, instead of accumulating and remaining only in the higher ones. By promoting this nutrient flow across all levels, the terraces maintained a relatively dynamic nutrient circulation system for the naturally shallow state of the soil. In the dry, harsh growing environment, this effective system of irrigation is especially critical for maintaining a system of closed nutrient cycling promoting the long-term sustainability of this agricultural system. Beyond nutrients, irrigation also allows for high levels of biodiversity, which contribute significantly to the productivity of the terraces. The Hani flood the terraces from nearby rivers each year from November to March, creating large pools of shallow water. A main reason for this flooding each winter is to attract wildlife as a management tool. Carp are able to survive in the pools, and not only provide farmers with another source of food, but also control insects and weeds and enrich the soil fields through waste fertilization. High levels of biodiversity (fungi, lotus and crabs) and effective irrigation systems have ensured the Hani people prevention against soil erosion, and allowed the terraces to remain an effective and amazing method of traditional agriculture for over a thousand years.
These examples of traditional agricultural techniques all share several principles that make them more sustainable than modern commercial agriculture. High biodiversity, no artificial inputs, nutrient cycling in a closed system, and cooperative working with the earth's natural processes are traits characteristic of traditional and sustainable farming practices. By emphasizing the importance of natural processes and incorporating these principles of traditional agriculture, we can work towards ensuring the long-term productivity and sustainability of our own food industry.