Flooded marsh

Figure 9. Flooding has broken this salt marsh into smaller pieces. (Photograph by the author. More about the photograph)

Rising sea level also breaks up continuous expanses of salt marsh, like those shown in Figures 6 and 7, into smaller habitats like the one shown here. Isolated islands of salt marsh are often, but not always, a sign of rising sea level and marsh erosion.

The dominant plant of the regularly flooded marsh shown in Figures 6 through 9, smooth cordgrass (spanrtina alterniflora), rarely reproduces by seed. In most cases it spreads gradually by extending roots that sprout new shoots. Therefore, most islands of salt marsh result from loss of connections to the larger marsh nearby. That is the case shown in Figure 9, although the telltale proof — the cliffed edge of the island — cannot be seen, because this picture was taken when the cliff was under the flooding waters of a high tide.

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