South Dakota Project Reveals Benefits of Healthy Soils
International Year of Healthy Soils -
Effectively all the food we humans consume grows from soil, yet we still are largely ignorant of the rich, wildly diverse ecosystems that exist beneath our feet and are essential for our existence. More pointedly, while U.S. agricultural productivity continues to rise, the basis for achieving this – using ever greater amounts of fossil fuels, synthetic fertilizers and biocides to produce food – is inherently unsustainable.
It's estimated that nearly one-third of the Earth's land area is degraded, adversely affecting some 3.2 billion people who rely on this land for their food and livelihoods. Besides degrading the long-term health of soils by drawing down organic content and minerals faster than they are being replaced – modern industrialized farming presents numerous environmental and social threats – from land, air and water resource pollution and resource degradation to land grabs and the monopolization of markets for seeds and crops.
Recognizing these problems and the crucial, foundational role soils play in human civilization, the United Nations (UN) has declared 2015 the International Year of Soils. Reporting on the results of a long-term study conducted at South Dakota State University, researchers found that that “tillage practices that conserve moisture, plants that use water more efficiently and soil with more organic matter have produced higher yields even in dry conditions.”
Healthier soils, healthier food, healthier people
The UN Food and Agriculture Organization (FAO) summarizes the root causes of soil erosion and degradation, the grave threat they pose for global society, and a more holistic, system-wide means of resolving the issue:
“Our soils are in danger because of expanding cities, deforestation, unsustainable land use and management practices, pollution, overgrazing and climate change.
“The current rate of soil degradation threatens the capacity to meet the needs of future generations. The promotion of sustainable soil and land management is central to ensuring a productive food system, improved rural livelihoods and a healthy environment.”
Current rates of soil erosion and degradation are compromising our ability to produce enough food to feed the ongoing, unprecedented increase in human population. In the updated and expanded edition of his book, “The Sacred Balance,” geneticist, ethno-ecologist and environmentalist David Suzuki highlights the net energy deficit, and hence unsustainable nature, of our industrialized, fossil fuel-driven agricultural system from the narrow yet fundamental perspective of energy balance alone:
“The enormous productivity of modern agriculture results from converting fossil fuels to food with a net loss in the conversion.”
No-till ag with crop cover
Advocates of sustainable agriculture, as well as environmental justice and economic equity, continue to work to develop more holistic, sustainable agricultural methods and foster grass-roots adoption by farmers around the world.
At the same time, they are trying to counter the political and economic influence of, and the public relations campaigns funded by, gigantic multinational agro-industrial corporations. South Dakota State University (SDSU) professor of plant science David Clay can be counted among them.
At the research team's plot at SDSU, soil carbon levels rose 24 percent during the 1985-2010 study period. Coincidentally, corn yields increased 73 percent. In addition, improving soil conditions results in the storage of greater amounts of water and carbon – effects that are especially important given current changes in weather patterns and precipitation levels.
"Higher organic matter content means the soil can store more water, which improves the crop's ability to resist drought and to fully take advantage of genetic enhancements," Clay was quoted in an SDSU research news report.
*Image credits: 1) UN FAO; 2) USDA Economic Research Service; 3) USDA Natural Resources Conservation Service; 4) Soil Science Society of America