we conducted a series of field experiments manipulating bioturbation intensity in a S. altern iflora salt marsh and bare intertidal mudflat (see Fig. 1). Each experiment had three treatments (6 replicates each one): (1) unoccupied burrows (thereafter B treatment); (2) inclusion of adult crabs N. granulata in burrows (thereafter B+C treatment); and (3) exclusion of crabs and burrows used as control (thereafter NBC).