Effects of freeze-thaw cycles on soil structure under different tillage and plant cover management practices

Soil structure plays a central role in many soil processes that are environmentally relevant. Intermittent freezing of the over winter is an important abiotic disturbance temperate climates and its effects on depend soil’s preexistent structural strength cohesion. Management choices such as tillage plant cover after harvest strongly influence structure, therefore response to freeze-thaw. We examined 5 freeze-thaw cycles (FT) µCT-detectable intact topsoil cores (Ø=100 mm, h=80 mm) from long-term rotation experiment Denmark. The were divided among two treatments treatments, corresponding gradient strength: CT-B1020 µm) analyzed macroporosity (V t ), mean diameter (d m ) Euclidian dis ance nearest (ED ). Additionally, we several µCT-derived geometric parameters Full Range. Overall, NT-B NT-V resulted lower than CT-B CT-V. Similarly, found fewer, less branched macropores with shorter branch length NT compared CT for both treatments. However, propose might be confounded by overlapping relatively few, complex voluminous coarse more abundant, very fine macropores. Freeze-thaw, turn, caused crumbling around macropores, reducing V d Range > 1020 range. FT significant increases reductions ED < 300 range, indicating creation new expansion previously indiscernible reduced (for equal treatments) treatments), greater resilience against cases. • was investigated via μCT analysis size. Freeze-thaw expands reduces macroporosity. No-till longer diminish changes cycles.