To determine the grain size composition of the sediment, 5
replicate sediment samples were collected from each site and
vegetation type using a 5-cm-diameter PVC corer to a depth of 5 cm. Approximately 30 g of sediments were sieved through 2-, 1-,
0.5-, 0.25-, 0.125, and 0.063-mm mesh sizes and were dried for 24 h
at 105 C. Each fraction was weighed to the nearest 0.1 g. The
median grain size and inclusive graphic standard deviation (sorting
coefficient) were determined graphically using a cumulative
percentage curve (Holme and McIntyre, 1984).