Surface sediments in seagrass meadows within a 5 m radius
were collected at each sampling station using a hand corer (3 cm
diameter, 5 cm deep, n = 4). Sediments were homogenized and
dried in glass vials at 40 C for analysis of OM. Sediments of
another 4 core replicates were split in half. One part was transferred
into 50 ml centrifuge tubes containing 10 ml 1 M ZnAc and
stored frozen, while the other part was stored wet and cool in
zip-lock bags for grain size analysis.