A New Mexico State University scientist’s work in carbon sequestration at Leyendecker Plant Science Center is getting attention — not just in New Mexico, but also in Austria and Australia. His work suggests a solution for dealing with carbon dioxide-related problems causing global warming.
The nearly seven billion people on earth have a collective carbon footprint more than 30.5 billion tons of carbon dioxide per year, from energy usage alone. If reducing this footprint will return the planet to more moderate climatic conditions, experts say we need a safe and inexpensive system to efficiently capture carbon dioxide from ambient air and safely store it, with few negative impacts on the economy or environment and no long-term liabilities for storage.
David C. Johnson, NMSU research scientist and molecular biologist at WERC, a consortium for environmental education and technology development housed in the College of Engineering, does research for the Institute of Sustainable Agricultural Research at NMSU.
“We have plenty of issues in both our climate and in agriculture,” Johnson said. “What this research pursued is how to best capture that CO2 and get it back in the soil, while also improving our agricultural systems. It turns out that our farmers are ‘the key’ to successfully reducing greenhouse gases within a sustainable agricultural system.”
His work started with a U.S. Department of Agriculture project, trying to solve the problem of what to do with manure from dairy cows. The USDA wanted a product that would sell and also would be good for agriculture, so Johnson developed a composting process that reduced the salinity of the manure, while creating a reduced-salinity compost that was good for the soil, but most importantly, it contained a diverse microbial community structure.
“The process we developed was a no-turn process, so you didn’t disrupt the fungal community, allowing it to thrive,” Johnson said. “What we noticed while growing plants in this compost is what focused us onto how to change soil, and how to move the soil microbial population from a bacterial to fungal-dominated community.”
Why is Johnson’s compost so unique?
“It’s not so much making the compost, but it was the change in plant growth we observed when we shifted the soil microbial community structure, moving it from bacterial-dominated to fungal,” Johnson said. “That’s what we’re now trying to do in agriculture – trying to shift the microbial community structure in soils.”
This isn’t accomplished by applying compost, as that is not practical for the large acreages agricultural producers manage. Instead, the Institute of Sustainable Agricultural Research is trying to implement this by growing it into the soil.
“This is basically how soils evolve – different plants will come in and grow, and they’ll have a certain influence on that soil, as far as being able to increase the carbon content. That seems to be the key here,” Johnson said. “The carbon plants capture using the CO2 in the atmosphere is an energy substrate. Soil organisms, like our society, depend on energy. As you add more energy into the system, you increase population density. A little more energy, you change the population structure, diversity develops and you begin to get specializations. When you achieve sufficient energy resources, you start to notice mutualisms between plants and soil microbes.”
Johnson’s research was recently highlighted in a book called “The Soil Will Save Us,” by Kristin Ohlson.
“I’m trying to bring all the players back in and let them do what they do best for capturing carbon and improving soil fertility. This will have such an impact on agriculture as far as being able to grow plants better, with less input, less water and cutting back on the downstream pollution we see from all of the fertilizers we apply to the soils,” Johnson said. “It will change the way we approach agriculture. And, my waste product from reducing atmospheric CO2 concentrations is food. Can you beat that?”