Healthy soils, healthy environment
The University of Minnesota’s growing emphasis on regenerative agriculture is changing the landscape of environmental health.
In our continuing quest to develop abundant and healthy food sources while protecting the environment, a new term has become prominent in the lexicon: regenerative agriculture.
“Regenerative agriculture is a movement to figure out how to produce food, fuel, and fiber in a way that not just conserves our natural resources and environment, but actually restores some of those natural resources,” says Jake Jungers, associate professor in the Department of Agronomy and Plant Genetics in the College of Food, Agricultural and Natural Resources Sciences (CFANS).
“I think that consumer interest around sustainability and awareness of what they’re consuming—what its impact is on the planet—has resulted in businesses paying more attention to where and how they source their products,” he adds. “And I think regenerative agriculture is very much a new way of branding the products coming from regenerative farms.”
In regenerative agriculture, the emphasis is often centered on soil health, Jungers says, and on what practices farmers can adopt as a foundation to sustainable agriculture.
Soil has three components: physical, biological, and chemical. For the physical, it entails aggregate stability (think clumpiness)—a quantitative measure that’s critical to its capacity to hold water. “Reducing tillage is a great way to promote aggregate stability,” he says.
The soil’s microbial activity and health comprise the biological piece. And the chemical aspect pertains to fertility—the nutrients that are available in that soil and how readily available they are for the crops to produce yield. “And all three of those pieces are intricately connected,” Jungers says.
There are a couple of broad movements to improve soil health. One is to increase continuous living cover on fields so that uncropped soil isn’t exposed to weather events that might lead to erosion and the degradation of nearby water systems.
This includes cover crops and also perennial crops in general. They provide that continuous living cover with roots in the ground, continually growing. This is the focus of the University of Minnesota’s Forever Green Initiative, which has been at the forefront of this movement. (See sidebar.)
Another movement is a return to more integrated crop-livestock systems. “That is a really popular component of regenerative agriculture—getting animals back on the landscape,” Jungers says. “Over the last 50 years, farmers have been incentivized to specialize in [what they produce]. Because of that, animals and crops have gone in different directions. There are farms that just do animals and farms that just do row crops.”
Row crop farmers often need to use synthetic fertilizers, which may result in uneven intake and unwanted spread across the landscape. And livestock producers may face an excess of nutrients and not know how to get rid of them sustainably.
“So, going back to the integration of the crops and livestock on individual farms can close the loop on those nutrients,” says Jungers.
A movement to diversify cropping systems
Diversifying the types of crops farmers grow on their farms can help achieve the goals of regenerative agriculture, but a diversification strategy must be economically viable.
Jeff Strock is a professor in the Department of Soil, Water and Climate in CFANS and is housed at the University of Minnesota’s Southwest Research and Outreach Center (SWROC) in Lamberton, Minnesota. His work is at the intersection of production agriculture and environmental quality.
A project earlier in Strock’s career at the SWROC helped shape his current research. He was doing a comparison of two adjacent 160-acre parcels of land. One contained corn and soybeans while the other had a mix of corn, soybeans, wheat, alfalfa, and some prairie areas.
He then analyzed the two plots for water and soil quality. Even accounting for other variables, there were quantifiable variances.
“The differences that we saw were really because of cropping system diversity,” he says. “It started to occur to me that we could probably solve a lot more of our water quality problems by really looking at cropping system diversity and rotational diversity.”
Then about a dozen years ago, Strock was approached by colleagues at the Southern Research and Outreach Center in Waseca, Minnesota, about the idea of developing long-term ag research in Minnesota. That led to the birth of the University’s Long-Term Agricultural Research Network (LTARN), which is allowing Strock and colleagues to actually test hypotheses about various cropping systems.
Testing diverse cropping systems at the LTARN nodes includes planting alfalfa and small grains like spring wheat that grow much earlier in the season. “So they’re using water to produce plant biomass a month or a month and a half earlier than traditional corn,” Strock says. “When the plants are growing for 4-6 weeks more than when you just plant soybeans, that has a huge effect on the hydrology… in a good way.”
Adds Strock: “And if we integrate some level of animal agriculture back on the landscape along with this idea of cropping system diversity and alternative crops, it’s really going to have an advantage in improving soil properties … as well as helping deal with our water quality problems.”
