Does soil's organic carbon content change over the year?

Thulfiqar Al-Graiti, a recently graduated PhD student at the Department of Environment and Landscape Geography, published the results of his thesis with the title “Seasonal changes of soil organic matter composition in separate carbon pools of a cultivated Chernozem: The role of crops and fertilization”. The paper, published in the Q1 journal "Geoderma Regional", presents the results of the soil organic matter monitoring in a long term fertilization field trial on a Chernozem. The main results suggest that soil organic matter, as one of the most widely used indicators of soil health, varies seasonally, i.e. a single annual sampling may not be enough to get an accurate picture. This recognition could be essential for an outline of a support monitoring system based on soil organic matter content and composition.