New Research Examines Rock Dust’s Impact on Nitrogen Cycle

The nitrogen cycle is perhaps one of the least understood and most complicated of nature’s cycles, especially when basalt is added to the system, according to Rock Dust Local founder Tom Vanacore.

Tom Vanacore (left) and Ben Dobson (right) at Stone House Farm. (Click to enlarge.)

He adds, this makes it a topic worthy of further investigation. Vanacore notes scientists in the U.S. Midwest have observed changing nitrous oxide levels when NPK and basalt were spread across conventional farms, indicating rock dust does interact with the nitrogen cycle.

“They looked at water and saw an increase in nitrate concentrations in the bio-water. This is out in Illinois where there is black dirt and they’ve been farming conventionally for years. It made me think about the nitrogen cycle and where the nitrogen is going. Or, if you’re decreasing nitrous oxide, what’s the implication of that?

“Maybe nitrates are increasing because [farmers] are putting [rock dust] over nitrogen fertilizer, and so in other words they haven’t adjusted for the fact the basalt will increase the efficiency for whatever reason.”

Working with Vanacore and other scientists, as well as Remineralize the Earth, Hudson Valley’s Stone House Farm has made available trial plots to study the effectiveness of basalt and biochar in farming.

Among other things, this research will look at impacts on the nitrogen cycle. Farm manager Ben Dobson notes Stone House Farm recently invested in several automatic data-logging instruments measuring the entire water cycle on a plot.

“These data loggers, every single day, twice a day, will automatically test for nitrates in the water, dissolved organic compounds, turbidity and a couple of other measures,” he says, adding he wants to grow perennial grass on these plots, rather than just stick with more conventional crops. “It’s not good to monocrop corn on corn on corn.”

This new research project fits into the Stone House Farm mission, which, as described on their website, is to demonstrate “a viable model of regenerative organic agriculture and to the development of a resilient agricultural economy.” To further this mission, they have “transitioned from conventional corn and soy production to being a diversified organic farm. They integrate their cropping and grazing systems to rebuild their soils and minimize their use of off farm inputs.”

Grassland matters: The need for more crop balance

Healthy grass is actually the most important crop for climate, notes Dobson, which is why it is the most relevant and feasible crop for Stone House Farm to invest acreage towards as part of its new research project. He argues that the U.S. simply harvests too much of select crops and too little of plants the planet needs most.

“The biggest problem with American agriculture is that we have oversupply of every single commodity,” he says, noting overabundance of a few select crops negatively impacts their economic viability for farmers. “These are also the biggest polluting crops we have, and so we very much need more and healthier grasslands across the world.”

Dobson adds: “Most of the Asian steppe is unhealthy grassland. The American West is desertifying rapidly because it’s unhealthy grassland. The African Savanna is desertifying because it’s unhealthy grassland.”

One method of restoring unhealthy grassland is Holistic Management. Stone House Farm uses “the principles of Holistic Management and a long term crop rotation in which we integrate our cropping and grazing systems to rebuild our soils and minimize our use of off farm inputs.”

Regenerative agriculture equals atmospheric health

Ben Dobson (left), Dr. Jim Tang (middle), and Dr. Tom Goreau (right) at Stone House Farm. (Click to enlarge.)

According to Thomas J. Goreau, Remineralize the Earth Board Director and an advisor on the Stone House Farm research project, regenerative agriculture using broken-down rock dust to remineralize the earth is not just good for the soil, food and farmers, but it is also good for groundwater and the atmosphere.

“When we use rock powder, firstly we’re releasing nutrients the plants need, but at the same time that weathering is converting CO2 to bicarbonate,” says the esteemed biochemist. “One of the things we don’t have really any good quantification on, and that we need to get, is just how efficient that is as a global carbon sink.”

Chemical weathering of rocks is a slow process, he notes, but when plants secrete that CO2 into soil minerals and organic acids, it boosts weathering by hundreds of times over background chemistry thanks to biochemical reactions. When scientists assess the role of remineralization in facilitating agricultural carbon sinks, he adds, often they are not thinking about that biological positive feedback loop. It is important to measure bicarbonate production in the field.

“If you measure composition of the [groundwater] screen, you can understand: Are you increasing the bicarbonate going into the rivers? Also, you understand bicarbonate is accompanied by potassium, sodium and other cations, and so if you look at chemistry, then you can understand the extent to which you recycle your important cations. Quantifying bicarbonate loss is really important.”

Carter Haydu is a writer, reporter, and journalist based in Alberta and Saskatchewan. He works for JuneWarren-Nickle’s Energy Group, with regular articles appearing in the Daily Oil Bulletin. He is a freelance columnist with the award-winning Quad Town Forum weekly newspaper, based in Vibank, Saskatchewan. He also contributes content for a series of magazines in and around Regina and Saskatoon. He received a BA in Political Science and Philosophy from Augustana University College in 2001 and a diploma in journalism from Grant Macewan College in 2005.

Resources for regenerative farming and large scale restoration

• The Savory Institute (https://www.savory.global/)
• Ecosystem Restoration Camps (https://www.ecosystemrestorationcamps.org/)
• John D. Liu’s Green Gold (https://www.youtube.com/watch?v=YBLZmwlPa8A)
• The Land Institute (https://landinstitute.org/)