Aggregates formation is a key process of soil development and carbon (C) sequestration. Even if there are theoretical approaches of soil structure formation, there are still unanswered questions, regarding the link of aggregates formation and C stabilization in soils.
Aggregates are not homogeneous in their size (macro- and microaggregates) and include C fractions of various availability (free and occluded particulate organic matter, C associated with clays). Due to this complexity, it is still not clear how C is transferred between fractions. Soil structure is a dynamic system, and proportions of aggregate size classes vary around the year. Besides natural processes, agricultural practices also affect soil structure, frequently leading to decrease of macroaggregates portion and increase of microaggregates. The combined effect of these two factors on soil structure and C stabilization in aggregates is still an open question. On top of the complex composition and temporal dynamics, fractionation methods have a strong impact on the obtained proportions of aggregate fractions. Thus, it directly influences the findings about the role of aggregates in C stabilization. This session invites contributions related to aggregates turnover, modeling of C stabilization in aggregate fractions, as well as the latest progress in fractionation techniques.