What is solifluction primarily associated with?

Solifluction is a type of soil flow that primarily occurs in regions where the ground is underlain by permafrost. This process involves the gradual, slow movement of saturated soil down a slope, which is exacerbated by the thawing of the active layer during warmer months. Permafrost, which is ground that remains frozen for multiple years, creates a barrier that prevents water drainage, leading to oversaturation of the upper soil layer when it thaws. This oversaturation makes the soil more susceptible to movement under the influence of gravity, resulting in solifluction.

The other choices represent environmental conditions that do not have the characteristic freeze-thaw cycles associated with solifluction. Desert regions typically experience low moisture levels, which would not lead to the saturation necessary for solifluction. Temperate forests and coastal areas do experience seasonal changes, but they lack the permafrost conditions that drive this specific soil movement.