Beneath the surface: Soil health expert discusses practices for healthy micro biome

Innumerable microorganisms below the soil surface are imperative for maximizing soil heath and productivity.

Natural Resources Conservation Service (NRCS) West Regional Soil Health Team Leader Jennifer Moore-Kucera noted that effective management strategies are critical to promoting a healthy soil micro biome.

In a presentation hosted by No-Till Farmer, Moore-Kucera discussed the vital role of soil life, as well as approaches for management.

“The question is, how do we manage and tap into this life force that is below ground and is really operating behind the scenes to keep the whole system going?” said Moore-Kucera.

Viewpoint

According to Moore-Kucera, the way soil specialists view organic matter is changing.

She noted that the traditional view relies on the formation of stable humus products.

“It observes organic matter properties and alkaline extracts that really don’t exist in nature when we get to the molecular level of organic matter,” said Moore-Kucera.

Now, scientists are transitioning to an emerging view that focuses on microbial access to soil organic matter.

“Overall, it emphasizes the need to manage carbon flows rather than carbon pools,” she commented. “What fuels the microorganisms and the biology below-ground is the flow of carbon in different forms, different labile or active pools of carbon that stimulates that microbial population.”

While the more passive pool of carbon is important and aids in carbon sequestration, Moore-Kucera explained that the flow of the labile pools of carbon is the most important in stimulating the microorganisms.

“By focusing on how to maximize this flow of carbon through soil and through the life and death cycles of the soil organisms, we’re better able to create healthy soils and sustainable land use systems,” she continued.

Protection

Moore-Kucera explained that NRCS created four general soil health principles to achieve the goal of optimal soil health and sustainability.

“These include to minimize disturbance, to maximize soil cover, to maximize the duration of living roots and to maximize diversity,” she said.

Moore-Kucera further condensed them into two basic principles, which are to protect the home and feed the system.

  “We’re minimizing disturbance and maximizing soil cover, which protects soil aggregates and soil organic matter,” she commented.

Moore-Kucera continued, “These actions also reduce erosion and runoff risk. By covering the soil, we’re buffering temperature, keeping water and nutrients in the root zone and reducing leaching losses.”

She noted that these principles primarily focus on protection of the microbial habitat.

Feeding system

The two principles that feed the system are maximizing the presence of continuous living roots and maximizing diversity in the system.

Maximizing diversity can be through the addition of crop rotations and the use of cover crops, as well as the integration of animals on a landscape.

“These principles aim to provide those diverse, labile carbon sources throughout the year, as well as the bio-chemicals that fuel the organisms and stimulate the plant-microbe interaction,” said Moore-Kucera.

Because of the stimulation of the plant-microbe interaction, several results can be seen, including breaking disease cycles, increasing soil organic matter and improving nutrient cycling.

“We enhance that internal nutrient cycling when we capture more of the nutrients that are applied and hold onto them for future use by plants, keeping them out of the groundwater and surface waters, for example,” continued Moore-Kucera.

Increased diversity also results in increased predator and pollinator populations, she explained.

“Doing this promotes the complex food web to enhance nutrient cycling. It stimulates the microbial population and increases predators that deliver organic matter,” noted Moore-Kucera.

Management

The overall goals of management systems are to feed the soil organisms and protect their habitat, while applying practices in a purposeful manner, said Moore-Kucera.

“Being in agriculture, we may need to add inputs to the soil, or we might need to address a pathogen or a disease pressure,” she commented.

Moore-Kucera continued, “We always want to make sure that whatever choice we’re making, it has a purpose. We should make decisions because we’re reacting to a different system, and we want to stimulate an internal resiliency within the system.”

Rather than focusing on single issues, she advised developing soil health management systems.

Examples of how to develop a comprehensive management system include enhancing crop diversity, reducing soil disturbance and integrating the use of inoculation with beneficial organisms or nitrification inhibitors.

“We can couple how we choose plants and above-ground inputs with soil management practices that reduce tillage and reduce disturbance,” she noted. “Mulching can also be a practice that sustains soil organisms and leads to organic matter formation, habitat formation for biological communities and advanced nutrient cycling.”

Moore-Kucera concluded, “These all lead to enhanced nutrient use efficiency, reduced nutrient losses, plant health, plant resistance and drought resistance.”

Emilee Gibb is editor of Wyoming Livestock Roundup and can be reached at emilee@wylr.net.