According to the United States Environmental Protection Agency, “sustainability is based on a simple principle: Everything that we need for our survival and well-being depends, either directly or indirectly, on our natural environment.”
Present conditions suggest that humans failed, in the recent past, in coexisting with nature. As a result, we risk permanently damaging the very resources that our children, their children, and beyond, require for survival. Conserving the biodiversity of both plants and animals continually dogs us. Droughts threaten various areas of the world, many of which are prime food producing sites. Misuse of the land not only destroys the health and vitality of what we grow our foods in, but also causes that earth to erode or float away in clouds of dust.
The Great Dust Bowl
During the Great Depression, a drought struck the Great Plains region of the United States. The result was the Dust Bowl. Historically, the Great Plains were covered with grasses with root systems that held soil in place. As America expanded westward, sustainability was the last thing on anyone’s mind. People used the plains to graze large herds of livestock. Others plowed and planted crops such as wheat. With the natural grasses no longer there to hold things in place, disaster was close at hand. It arrived with the onslaught of the drought.
Throughout history, civilizations rose and fell with meteorological calamities. The United States survived the Dust Bowl and the Great Depression. However, other areas now suffer through dust events, including Northern China and southern Mongolia, and sub-Saharan Africa. In both areas, overgrazing by livestock brought on the problems, according to the Earth Policy Institute.
In America, according to National Geographic, “a new Dust Bowl is…engulfing the same region that was the geographic heart of the original.” The area where Kansas, Colorado, and the Texas and Oklahoma panhandles come together has had less rain in recent years than what fell in the original Dust Bowl.
What makes up the concept of soil sustainability? Soil is a complex medium with many components. The number of organisms and processes that make dirt into fertile soil is mind-boggling. Consider the following facts about soil provided by the Environmental Protection Agency:
- Soil contains organic matter (living and dead organisms), in addition to minerals and nutrients
- It can take over 500 years for one inch of topsoil to form through natural processes
- Fungi and bacteria break down organic matter
- Plant roots and lichens break up rocks into the small particles that become part of new soil
- Earthworms make soil richer by digesting organic matter
- Even rodents play a part, as their burrows aerate the soil
- Soil consists of about 45 percent minerals (such as sand, silt, and/or clay), 25 percent water, 25 percent air, and five percent organic matter
- Types and content of soil varies widely, with more than 70,000 types identified in the United States alone
However, many modern agricultural practices impair processes that create sustainability in soil. Pesticides kill beneficial bacteria and fungi that break down organic matter. Herbicides kill plant matter. An unhealthy cycle ensues.
Real World Soil Sustainability
Farmers must identify and adhere to soil sustainability plans, which allow the organic processes of soil creation to continue.
The EPA identifies several soil management aims to increase the availability and plant uptake of water and nutrients, including:
- Replenishing soil moisture
- Increasing the amount of organic matter in the soil
- Keeping soil and its nutrients in place, rather than losing it through erosion
Improving the surrounding areas’ soil quality also depends upon sustaining the soil by preventing runoff of agrochemicals into other land and water sources.
Gilberto Salazar, a Study in Soil Sustainability Practices
Global G.A.P. is an organization that certifies good agricultural practices. It addresses not only the process of growing, packaging, and processing, but also caring for the environment and maintaining biodiversity in agricultural operations. One grower with Global G.A.P. certification who embraces soil sustainability is Gilberto Salazar, head of Videxport in Sonora, Mexico. Three of the techniques used on his fields are proven soil conservation methods.
An irrigation drip system is a sustainability practice that provides two benefits: water and soil conservation. Drip irrigation provides a slow but steady flow of water to a plant’s roots system. Plastic tubes placed near a plant’s roots (sometimes even placed beneath the ground) supply the plant with plenty of water without wasting any, such as what occurs with sprinklers and other watering methods.
Seeking out other sustainability options, Salazar’s operations began utilizing natural barriers. The use of natural barriers encompasses everything from planting trees as windbreaks to employing contour plowing and planting to follow the natural rise and fall of the land. By working with the land, rather than restructuring it, the soil retains nutrients and remains in place.
Another method employed by Gilberto Salazar in his agricultural operations is tilling the land in a manner that retains soil integrity. Tillage refers to preparing soil for a new crop planting. Some widespread methods of tillage actually contribute to soil loss. However, according to Sustainable Conservation, conservation tillage significantly reduces dust and diesel emissions, saving farmers millions of dollars in fuel costs, labor costs, and maintenance. There are several methods of conservation tillage. In general, the process involves leaving crop residue (such as corn or wheat stalks) from prior harvests on fields before and after planting a new crop. Doing so reduces soil erosion and runoff.
Sustaining the World for the Future
The Latin roots of the word “sustain” are “tenere,” which means to hold, and “sub,” meaning from below. Sustainability literally means supporting something, or holding it up from below. This is apt for any discussion of soil, since, without strong, healthy soil, our food sources may disappear.