As producers continue to face climatic pressures, research on the resilience of agricultural systems becomes increasingly important. In addition to reducing synthetic inputs and promoting biodiversity, organic systems may strengthen long-term soil health and increase the soil’s capacity to store carbon and nitrogen. A 2025 study examined how 34 years of organic management influenced soil organic carbon (SOC) and total nitrogen (TN) storage. The researchers found that organic systems, especially those using composted manure, built up higher levels of soil organic carbon and nitrogen than conventional systems.

The study analyzed soils from Rodale Institute’s Farming Systems Trial in Pennsylvania, one of North America’s longest-running side-by-side comparisons of conventional and organic farming. Researchers sampled conventional, organic legume-based, and organic manure-based systems, and evaluated soils at multiple depths under both conventional and reduced tillage. Organic systems consistently demonstrated higher SOC and TN concentrations in the top 20 centimeters of soil compared to conventional systems. These results suggest that long-term organic management, along with common amendments like composted manure and legume biomass, can improve nutrient retention and build soil organic matter over time. 

Although the study found clear benefits associated with organic systems, the authors noted that soil carbon dynamics are complex and can vary widely from year to year because of climate and management interactions. Future research should examine how organic systems influence deeper soil layers and whole-farm carbon balances over time. 

Overall, these findings highlight the importance of evaluating agricultural systems not only through yield, but also through broader measures of soil health, ecosystem resilience, and long-term sustainability.

Photos by Markus Spiske and Roberto Catarinicchia on Unsplash