"Carbon sequestration is the process of taking carbon out of the air and putting it in the soil," stated Martin Kleinschmit of Hartington's Center for Rural Affairs and sustainable ag specialist. "And the only place that can happen is through photosynthesis in plants."
According to Kleinschmit, soil carbon - also referred to simply as carbon or organic matter - is the most crucial element in our food production system that is not only greatly influenced by farming practices, but widely misunderstood and understated.
Through four different Natural Resource Development centers in Nebraska, Kleinschmit developed a testing program to help interested farmers learn fundamental practices to build soil quality through carbon sequestration.
"The way we can increase the amount of carbon in the soil is by having plants grow longer, and more plants growing," he said.
Program participants experimented with different methods of carbon-building practices such as planting cover crops, sometimes referred to as "green manure," incorporating grazing animals, opting to spread real manure instead of chemical fertilizer, and testing different crops grown and amounts of residues left in the field after harvest.
"When we're talking about using corn stalks and grasses, we have to think about how much we're taking away," Kleinschmit said, stating that farmers must add as much carbon to the soil each year as they use. "It is so, so important that this residue be recycled."
Carbon, in the form of soil organic matter, is a major source of plant nutrients and the major food source for most soil organisms. As the most valuable resource to a farm's long-term sustainability, carbon increases crop yield potentials, not just for the year at hand but for years to come.
"Carbon sequestration is the most critical thing, the most beneficial thing, that farmers can do," Kleinschmit said, explaining that the rapidly deteriorating soil quality from carbon deficiency has a huge downward spiral effect. "There are all kinds of bugs down there and bacteria do a really good job of breaking down things and they consume a lot of nitrogen."
It is the micro-organisms that change fertilizers into a form that the plant can use, so without them, absorption doesn't happen, he said.
"One tablespoon of soil has more living organisms than there are people on the earth," he said. And that same tablespoon of soil represents a small-scale replica of the bigger picture of our world. If farming practices don't care for the environment that sustains that living ecosystem within the soil, then we are destroying the soil's ability to grow anything, he said, and ourselves, right along with that.
In warmer climates, farmers need to keep adding more carbon just to stay even, he said. And since temperature affects how fast the carbon is used - the hotter the temperature, the more carbon used - the need for practices that replace used carbon are now more important than ever.
"If the earth continues to warm, as is predicted, we're going to need more carbon just to maintain the levels. And this is happening at the same time we're looking for other uses for our carbon - like (bio-fuel)," Kleinschmit said.
Though the tests being done in the farm groups are far from over, Kleinschmit is encouraged by the results and the responses from participants.
"Many of the farmers I've worked with say, 'Why didn't anybody tell us this? This is really important.'"
And he said as inputs get increasingly expensive and as poor soil quality takes its toll, more farmers need to know how to remedy the problem before it gets worse. Low carbon results in erosion, inability of soil to absorb or retain water, lack of nutrients to growing plants, and inability for plants to utilize nitrogen.
"Most farmers are taught to think (Nitrogen, Phosphorus and Potassium)," he said. "These are the main inputs being sold, and that alone doesn't do a thing. It just lays there." He added that many of the synthetic additives destroy the natural environment in which carbon is produced. "That kills the whole process."
Kleinschmit stated that farmers wanting more information on carbon sequestration should approach their NRD.