System-wide Monitoring Program

Submerged Aquatic Vegetation

Submerged aquatic vegetation (SAV) includes all of the underwater plants that live throughout the estuary and near coastal waters. These plants grow only in those areas of the estuary that are shallow enough and clear enough to receive sufficient sunlight for photosynthesis. The salinity and temperature of a particular estuarine location determine, to a large extent, which species can survive. SAV supplies food for several types of waterfowl and small mammals. Like marsh grasses, SAV primarily provides huge quantities of decomposed matter (detritus) and as it dies, many aquatic species use it as a primary food source. SAV uses up excess nutrients that might contribute to eutrophication of an estuary, storing a summer pulse of nutrients for later release in the fall as detritus. SAV also provides habitat for organisms such as barnacles, and eggs of many species. SAV reduces erosion of shoreland zones by dampening the energy of incoming waves.

SAV requires specific physical and chemical conditions to remain vigorous. A healthy stand of SAV indicates a healthy estuary. The decline in the population density of SAV indicates change in ecosystem health.

Biological Monitoring

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