Beschreibung:
<p>Seasonal variation in the standing crop of the seagrass Syringodium filiforme and its associated macrophytes was studied in a northern basin of the Indian River, a large mesohaline lagoon in central Florida, near the northern distributional limit of S. filiforme. The minimum standing crop occurred from February through April and the maximum in September. Two other seagrasses, Halodule wrightii and Halophila engelmannii, together with a drift algal community, occurred in the study quadrat, but were not major components of the macrophytic system. The formation of sizeable sandy patches within Indian River seagrass beds is partially due to the burrowing activities of Limulus polyphemus. Thermal stresses associated with the northern geographical S. filiforme range may contribute to this phenomenon by restricting annual production, hence limiting patch regrowth.</p>