How should sand fences be placed to effectively re-establish dunes?

The effective placement of sand fences is crucial for re-establishing dunes, and positioning them perpendicular to the prevailing winds is the most effective approach. When sand fences are aligned this way, they catch and trap windblown sand. As the sand accumulates around the fences, it begins to build up, encouraging the development of new dunes over time. This method takes advantage of the natural wind patterns that transport sand, allowing for a more efficient accumulation and stabilization of sand in desired areas.

In contrast, placing sand fences parallel to the coast would not effectively capture the wind-driven sand, resulting in less accumulation near the dunes. Installing them at the base of dunes may not provide the necessary catchment for sand that is being moved by the wind, thus failing to promote new dune formation. Likewise, deploying the fences in random patterns would disrupt the natural dynamics of sand movement, leading to inefficient trapping and likely resulting in an inconsistent buildup of sand.