Beaches are for pondering the edges of life.
Coastal processes • Beach renourishment • Chicago's lake front • Boca Ciega Bay • Predation • Production • Beach transect
Coquina limestone can break down or aggrades into sand. Compare the compressed coquina clam shells with the grain sizes of quartz and silica sands.
Dunes =========== Back shore ======== Berm ======= Foreshore
Waves push sand onto the shore.
Rivers provide oceans with nutrients like calcium, carbonate, magnesium and silica, while brining sediments in the form of sand, silt, and detritus to estuaries where longshore currents carry the heavier sands along the shore (longshore currents) to build up beaches.
Long Shore currents, or littoral drift, moves sand and gravel from one place to another on a beach.
Groins or rocks placed perpendicular (at right angles) to the shoreline, called jetties, are no longer believed to protect beaches as they once were in the 1900s.
Dredged from the offshore, the sand is being replaced on this eroded beach:
Dredging of sand back on to eroded ocean shorelines is called "Beach renourishment" and it costs American taxpayers billions of dollars annually.
Critters of the Sea
Delicate creatures off shore, such as these marine ascidians are damaged due to dredging sand for beach renourishment. Marine ascidians, like all filter feeders --from salps to scallops, help to keep the water strained of debris, detritus and nutrients. Fish and snails then feed on these diaphanous creatures.
Coral Polyps
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| coral polyps feed at night | A coral is a symbiotic creature | Colonial Corals are the sea's oasis! |
Coral reefs are the foundation rock structures of some entire coastlines.
Algal blooms
Harmful algae blooms can occur when water along the coast is too enriched by nutrients. The HABS or Hazardous Algae Blooms kill fish, turtles, marine mammals, contaminate shell fish and can cause sickness in people. Organism such as these multiply and generate "red tides."
Waterfront Parks
Socially beaches are urban playgrounds, necessary recreational options for the poor and working class, close to their living and employment locations. Here Chicago's Grant Park reveals the visual importance of such public assets as accessible shorelines.
"A civilized landscape" one student writes suggests that "we should know better than to dispose of wastes."
Here abroad buffer between urban streets and ak Michigan helps to intercept rain water --especially from storms-- and allow it to enter the underground system we call ground water flow.
Bays in Florida attract development promoting hazardous algal blooms, HABS, due to polluted run-off, septic tanks, and fertilizer.
In the upper left hand corner of the photo (Northwest) natural reserves of Cayo Costa State Park and Honeymoon Island municipal park can be seen in stark contrast to the developments along most of Clearwater Beach and Boca Ciega Bay.
Boca Ciega Bay, in Clearwater, suffers from pollution due to:
In the upper left hand corner of the photo (Northwest) natural reserves of Cayo Costa State Park and Honeymoon Island municipal park can be seen in stark contrast to the developments along most of Clearwater Beach and Boca Ciega Bay.
Coral reefs are the Oases of the Seas, and yours is the last generation that will be able to experience their dramatic depth of color, diversity of organisms and
The sand beach is where the marine turtles nest.
