Experimental Studies on the Salinity Tolerance of Turtle Grass, Thalassia testudinum

The supply of fresh water to estuaries has become an increasingly important issue for water managers (Postel et al. 1996). Anthropogenic modiÞcations of river discharge by diversion, withdrawal, channelization, and damming have altered both the timing and quantity of freshwater delivery to estuaries (WhitÞeld and Wooldridge 1994; Hopkinson and Vallino 1995; Jassby et al. 1995). Unfortunately, the effects of altered freshwater discharge on downstream estuarine ecosystems and their component communities are not well understood (Hopkinson and Vallino 1995; Livingston et al. 1997). One estuarine ecosystem that is strongly impacted by altered freshwater discharge is the Caloosahatchee Estuary.