Southern new england habitats ii tidal marsh
Download
1 / 9

Southern New England Habitats II: Tidal Marsh - PowerPoint PPT Presentation


  • 169 Views
  • Uploaded on

Southern New England Habitats II: Tidal Marsh.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Southern New England Habitats II: Tidal Marsh' - howe


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Southern new england habitats ii tidal marsh
Southern New England Habitats II: Tidal Marsh

  • Definititon: Tidal marshes develop in the quiet water, low energy environments behind barrier beaches at places where freshwater streams enter the ocean. Such mixing zones between fresh and salt water are estuaries. They are subject to daily tidal inundation.

  • Physical environment: Tidal marshes also are an extreme environment, in that organisms living in them must tolerate tidal fluctuation and water salinity.

  • Diversity: As with beaches, richness of terrestrial species may be low, because few species possess the adaptations necessary to survive this environment. The density of these species may be high, however. Even marine species must contend with environments that are periodically flooded and that show wide swings in water salinity.


Topography the low salt marsh
Topography: the Low Salt Marsh

  • The area above the mid-tide level is the first to be extensively vegetated by terrestrial plants. Near the mouth of estuaries, this tidal water is highly saline, and tidal salt marshes develop.

  • The predominant species in this zone is a tall, coarse grass- salt marsh cord grass (foreground).

  • Below the mid-tide level, mudflats are exposed at low tide.

  • In New England, most low marsh occurs at the seaward edge of tidal marshes and along tidal creeks, such as the one in the photo.


High salt marsh
High Salt Marsh

  • Above the high tide level is a region flooded only several times a month by “spring” tides (tides associated with the full and new moon).

  • This high marsh is vegetated by a finer, tussock-forming grass- salt meadow cord grass.

  • Much of the surface of New England salt marshes is covered by high marsh.


Salt pannes
Salt Pannes

  • Low spots on the surface of the high marsh may fill with tide water, which is then trapped in them.

  • As the water evaporates, it becomes hypersaline, creating conditions which few plant species tolerate.

  • A stunted form of salt marsh cord grass grows in these areas, as does the fleshy-stemmed saltwort and various types of algae.

  • Numerous invertebrates may be found in pannes, and these are a valuable food source for species like migratory shorebirds.


Upper marsh
Upper Marsh

  • In areas with greater microelevations (elevations inches above those of lower parts), tidal flooding becomes even less frequent.

  • In these regions, plant species like spike grass and black grass (actually in the rush family; visible in the center of this slide) predominate.


Upland border
Upland Border

  • The upland border of tidal marshes are still less frequently affected by tidal flooding- usually only during wind-driven storm tides.

  • They are characterized by salt-tolerant herbaceous species like switchgrass (foreground) and woody shrubs like high tide bush and groundsel tree (white flowered shrub).



Adaptations
Adaptations

  • To inhabit the salt marsh, plants and animals have developed mechanisms to cope with environmental conditions.

  • The sharp-tailed sparrow (above) has kidneys that remove excess salt from its tissues.

  • The saltwort (left) has fleshy stems that helps to dilute salts in its tissues.


Brackish and freshwater tidal marshes
Brackish and Freshwater Tidal Marshes

  • Water salinity steadily drops upstream along estuaries, although tidal action may extend inland many miles.

  • When water is slightly salty, brackish tidal marshes dominated by reeds and cattails develop (below right).

  • Further upstream, freshwater tidal marshes dominated by bulrushes, pickerelweed and water horsetail develop (above right).


ad