Altamaha Basin > Hydrology > Water Quality > Environmental Threats > Human Impacts > Cultural Features > Coastal Habitats > Tributaries > Plants > Animals > Sapelo Island |
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The different growth forms of S. alterniflora, tall on creekbanks and levees grading into an intermediate height behind the levees and to the short form in areas farthest from creeks, collectively have a rate of annual production that rivals that of any natural ecosystem. In spite of decades of research, the cause of the different growth forms remains unclear. The bare mud banks of the creeks and larger drainage channels also support a flora which has relatively high rates of primary production, even though it is overshadowed by the production of marsh grass in ecosystem budgets. The diatoms that form a golden sheen on the surface of the mud when they are not covered by water migrate down into the mud when the tide comes in. They live in a nutrient-rich environment due to water seeping through the creek banks, but are heavily grazed by snails (llyanassa obsoleta) and fiddler crabs (Uca pugnax) when they are on the surface photosynthesizing. |
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