A review of carbon farming impacts on nitrogen cycling, retention, and loss.

Soil carbon (C) sequestration in agricultural working lands via soil amendments and management practices is considered a relatively well-tested and affordable approach for removing CO from the atmosphere. Carbon farming provides useful benefits for soil health, biomass production, and crop resilience, but the effects of different soil C sequestration approaches on the nitrogen (N) cycle remain controversial. While some C farming practices have been shown to reduce N fertilizer use in some cases, C farming could also impose an unwanted "N penalty" through which soil C gains can only be maintained with additional N inputs, thereby increasing N losses to the environment.