ABSTRACT
Changes in the amount, timing, or location of freshwater inßow are recognized as primary stressors to estuarine and marine seagrass species and communities. Progress has been made assessing impacts of too little or too much freshwater inßow, by using salinity as a Þrst-order stressor per se, and as an indicator of associated, second-order stressors. Seagrass species can be associated with typical mean values of salinity and also with extreme values of salinity where species persist or perish. But a growing body of anecdotal, observational, and experimental data suggests that patterns of salinity variation also have signiÞcant effects on seagrass presence, persistence, and condition.
