15 July 2026 ยท Nutrient cycling
The nitrogen question everyone skips
Ask anyone about regenerative grazing and soil, and the conversation goes straight to carbon: carbon credits, carbon sequestration, carbon claims on a spreadsheet somewhere. Nitrogen barely receives a mention, even though it is just as central to whether a grazing system is genuinely doing what it is claimed to do, and arguably easier to get badly wrong in ways that matter immediately rather than over a decade.
That is not a small oversight. A system can be adding soil carbon at a healthy rate and still be leaking nitrogen, or holding nitrogen so tightly that pasture productivity suffers, and both outcomes get waved through as "improving soil health" if nobody is actually measuring the nitrogen side.
What actually gets measured, and mostly does not
The nitrogen side of my fieldwork tracks inorganic nitrogen pools (ammonium and nitrate), total nitrogen, the soil carbon to nitrogen ratio as a marker of substrate quality, and phosphorus as a co-limiting nutrient that shapes how much of that nitrogen microbes and plants can actually use. In addition to the pools, I measure potentially mineralizable nitrogen through aerobic incubation over two to four weeks, microbial biomass nitrogen, and soil respiration as an indirect proxy for how fast decomposition, and therefore nutrient release, is happening.
None of that is exotic methodology, but standard soil ecology practice. What is missing is anyone routinely applying it alongside the sweeping claims made about regenerative grazing's benefits for "nutrient cycling," a phrase used constantly and quantified almost never.
Where this connects to the biology
This is also where the nitrogen story and the nematode story meet: soils where bacterial feeding nematodes dominate tend to cycle nitrogen quickly, sometimes faster than plants can capture it, whereas soils with more fungal feeding and higher trophic level nematodes, omnivores and predators, tend to regulate that release more tightly, holding onto nitrogen and releasing it on a slower, steadier schedule. The trophic structure of the soil food web is not merely a carbon story but a nitrogen story running in parallel, and testing that link directly, rather than assuming it, is a core part of this project.
Why this belongs in the ecosystem service conversation
When "improved nutrient cycling" is listed as a benefit of regenerative grazing, it is almost never backed by actual mineralisation data, nitrogen pool measurements, or microbial biomass nitrogen, but is instead an assumption riding on the back of the carbon story. My fieldwork treats nitrogen as its own research question, not a footnote to carbon, because a grazing system that gets carbon right and nitrogen wrong has not actually delivered the ecosystem service it claims to.