Climate Change and Organic Agriculture

By Bill Duesing…..

Many of us participated in the inspiring People’s Climate March on 9/21/2014 in New York City. Marchers represented a wide variety of religious, educational, environmental, energy, social justice, peace, health, labor, cultural and other organizations.  Though they all had their own agendas for solving problems and making the world a better place, they agreed that climate change is very serious and needs to be addressed.

From right, soil scientist, permaculturalist and CT NOFA founding Board member Cynthia Rabinowitz, CT NOFA Executive Director Eileen Hochberg and former executive director Bill Duesing at the beginning of the People’s Climate March.

Organic farmers and consumers marched with the “We Have Solutions” section. We’ve known for a long time that organic food and agriculture are an important part of the solution to many of our environmental problems.  Organic methods and systems are valuable tools for building health and biodiversity in the soil, in our communities and in our bodies.

Organic Solutions

We are just now understanding how organic agriculture not only slows down climate change and increases our resilience in the face of it, but also actually removes carbon dioxide from the atmosphere and stores it in the soil.  Organic agriculture even has a powerful potential to reverse some of the damage we’ve already done to the atmosphere.

The key organic methods which encourage carbon storage reduce or eliminate tillage and bare soil, keep the soil covered with a diversity of growing plants and eliminate synthetic nitrogen fertilizer.  Soil that is not disturbed encourages greater soil biodiversity, especially more fungal growth.  Fungi function as liquid carbon pathways, carrying energy-rich carbon compounds from plant roots to the billions of soil organisms surrounding the roots.  Between 30 and 60 percent of the carbon plants take out of the air flows out through the roots.  This carbon energizes nitrogen-fixing and other soil organisms which eventually turn it into long-lived humus, a safe carbon repository which greatly increases the soil’s water-holding capacity.

The Chemical Contrast

This organic advantage is nearly the opposite of what chemical agriculture does.  In many ways, from its production to its leaching into the environment, synthetic nitrogen damages our planet.

University of Illinois scientists studied the nitrogen fertilizer records and soil carbon levels at the Morrow plots, the nation’s oldest experiment field with records going back 100 years. Researchers found that chemical fertilizers deplete the soil’s organic carbon.  They discovered that synthetic nitrogen fertilizer had not only stimulated decomposition of all the organic residues (corn stalks, soy plants) that had been added to the soil over fifty years, but also had volatilized almost five tons per acre of carbon from the native soil.  Read the study HERE

All told they found that chemical nitrogen fertilizers had driven about 100 tons of carbon out of the soil, and into the air as carbon dioxide, from each acre of the experiment farm. Inorganic nitrogen, especially when combined with tillage, greatly damages the soil ecosystem.  It inhibits nitrogen-fixing organisms and the fungi that feed them with carbon exuded by plant roots.

In contrast, studies on four continents have shown that organic farming can store from just under a ton to over three tons of carbon, per acre, per year.  Multiply that by the number of crop acres world wide and you get a number close to the amount of excess carbon we need to remove from the atmosphere to stabilize the climate. Only the ocean can hold more carbon. Amazing!

The application of nitrogen fertilizer is also responsible for about three quarters of this country’s nitrous oxide emissions.  Nitrous oxide has 310 times the global warming potential of carbon dioxide.

All these greenhouse emissions are in addition to those released as inorganic nitrogen is taken from the atmosphere by the energy-intensive process to create nitrogen fertilizer using natural gas.  The whole process likely releases even more greenhouse gases if that natural gas is the result of hydraulic fracturing (aka fracking) which is becoming the norm these days. Read Tom Philpott’s explanation of how cheap gas from fracking and hefty subsidies from taxpayers are encouraging greater domestic production of this soil and climate destroying substance.

After all that pollution from its making and application, 60 to 90 percent of the applied nitrogen fertilizer is leached into water, volatilized into the air or immobilized in soil. Nitrogen pollution is responsible for dead zones on our coasts and undrinkable well water in the heartland. (See photo.)

Notice in a Kansas State Park, August 2014. Nitrates are from nitrogen fertilizer.

Look at the Summer and Fall issues of NOFA’s The Natural Farmer for more details on the soil, carbon and nitrogen connections.  Dr. Christine Jones’ articles are especially helpful.  (While you are looking at the Summer issue, be sure to read Connecticut “carbon farmer” Bryan O’Hara’s article, “No-Till Vegetables at Tobacco Road Farm.)

Put simply, chemical agriculture releases great quantities of greenhouse gases while organic agriculture sequesters them.

SLOW change

Despite the dismal reality, don’t expect a swift change away from chemical nitrogen to organic methods without a lot more activist pressure.

We’ve known about many of the advantages of organic agriculture for over 100 years. Knowledge alone won’t do it in the face of some giant corporations wanting to make and sell more chemical fertilizers (and pesticides and the seeds that need both). Other corporations demand access to low-cost feed for confined animal feeding operations, and to low-cost ingredients for soda, junk food and even beer.

Some rich and powerful entities are able to manipulate government programs and public opinion for their benefit while financially squeezing farmers and driving them off the land.

As a University of Minnesota ecologist notes in another Philpott article: …the problem lies not with farmers but with farm policy and the market/political power of agribusiness—a “behemoth largely created by lobbyists, trade associations, big businesses and the government.”

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