THE NATURAL COMMUNITIES OF VIRGINIA
CLASSIFICATION OF ECOLOGICAL COMMUNITY GROUPS
Second Approximation (Version 2.5)
Information current as of February, 2012
Tidal Mesohaline and Polyhaline Aquatic Beds
This group contains hydromorphic herbaceous vegetation of shallow estuarine bays, tidal creeks, and salt marsh pools. These communities occur along the Atlantic coast from Maine to North Carolina. In Virginia, habitats have salt concentrations > 5 ppt and are permanently flooded by tidal waters or occasionally exposed at extreme low tides. Species richness is very low, with one to a few submerged vascular aquatics present. These consist primarily of beaked ditch-grass (Ruppia maritima), common eel-grass (Zostera marina), horned pondweed (Zannichellia palustris), and sago pondweed (Stuckenia pectinata , = Potamogeton pectinatus). Aquatic algae are frequent to abundant associates. Although these communities are scattered throughout the eastern Virginia maritime zone, at present there are few data on their composition, distribution, and ecological dynamics in this region.
References: Moore et al
. (2000), Orth and Moore (1988).
REPRESENTATIVE COMMUNITY TYPES:
The two community types nested under this group are based on existing associations in the USNVC and are consistent with the findings of Orth and Moore (1988). Moore et al.
(2000) recognized several other communities in the greater Chesapeake Bay estuary. Inventory of this group is clearly needed, although it is limited by accessibility of sites and the taxonomic skills of surveyors and will likely receive little attention from DCR-DNH in the near future. Click on any highlighted CEGL code below to view the global USNVC description provided by NatureServe Explorer.
- Zostera marina Semipermanently Flooded - Tidal Herbaceous Vegetation
Tidal Mesohaline / Polyhaline Aquatic Bed (Sea-Wrack Type)
USNVC: = CEGL004336
Global/State Ranks: G4G5/SU
- Ruppia maritima Semipermanently Flooded - Tidal Herbaceous Vegetation
Tidal Mesohaline / Polyhaline Aquatic Bed (Ditch-Grass Type)
USNVC: = CEGL006167
Global/State Ranks: GNR/SU