Increasing drought conditions as a result of climate change are expected to cause more frequent and intense drying-rewetting (DRW) cycles in soils. Peaks of CO2 emissions released from the soil to the atmosphere upon rewetting have been well documented. One hypothesis for this carbon release is the physical deprotection of organic matter in soils due to modifications in pore network morphology. Soil structural stability during DRW cycles depends on soil properties (e.g. texture, carbon content), but should also depend on soil management practices in agroecosystems. This work aims to reveal for the first time the physical deprotection of organic matter in natural soils during DRW cycles using synchrotron-based X-ray imaging. Soil samples were collected from the 2-5 cm layer of two Luvisols under conventional and conservation agriculture respectively. The samples were air-dried and broken manually into aggregates of 2-3 mm, and their organic matter was stained with Osmium. 18 aggregates were subjected to 3 DRW cycles and scanned at 1.3 µm resolution before and after rewetting. More intense deformation was observed under conventional agriculture compared to conservation agriculture during the DRW cycles. Aggregates from conservation agriculture show thinner cracks and better structural recovery upon drying. Aggregates from conservation agriculture also contain more Osmium-stained organic matter. Further steps of this project will quantify interactions between the organic matter and the changing pore network during DRW cycles, and infer new relationships between soil organic matter decomposition and soil structure dynamics.