Salt Pannes and Pools

Salt pannes and pools are water-retaining depressions found within salt and brackish marshes. Pannes typically begin when a mat of organic debris settles on existing vegetation and kills it, creating a shallow depression that retains water through repeated cycles of flooding and evaporation, which raises the panne's salinity above that of the surrounding marsh and shapes the plants and animals able to live there; pools, which hold water longer between high tides, are secondary formations whose exact mechanism is not well understood.