What happens when the C:N ratio is high in organic material?

When the carbon to nitrogen (C:N) ratio in organic material is high, it indicates that there is a greater amount of carbon relative to nitrogen present. In this scenario, nitrogen is often retained in the organic matter as it is required for the decomposition process to occur more efficiently. Microorganisms that break down this organic matter utilize nitrogen, resulting in less nitrogen being available in the immediate soil environment.

The high C:N ratio means that while microbes feast on the abundant carbon, they need to acquire nitrogen, which may lead to a temporary immobilization of nitrogen. This can result in a situation where nitrogen becomes less available for plant uptake initially, as soil microorganisms will retain organic nitrogen until the carbon-rich organic material is sufficiently decomposed. Hence, more organic nitrogen is retained in the soil, which can later be mineralized and made available to plants after the carbon has been adequately processed. This understanding highlights the complexities of nutrient cycling in soil and the interdependencies between carbon and nitrogen within organic matter.