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Tuesday Feb. 12th Objective: I will know why mangroves matter and learn about open ocean ecosystems Agenda: Mangroves matter article Notes on sea-grasses and neuston Homework: Review for Thursday’s mini-summative (corals, neuston, mangroves, marsh, urchin)

Mangroves Matter Questions Answer on a separate sheet please 1. What % of game fish and shellfish caught in S. Florida depend on mangroves? 2. What are the scientific names of each of the 3 types of mangroves? 3. What accounts for most of the loss of mangroves? 4. In 1995 what law was passed? 5. Which exotic plants have to be cleared out to prepare a site for mangroves to grow? 6. Who is Dr. Brandt? 7. What will 2004 be remembered as?

Seagrasses marine plants covering extensive shallow underwater “meadows” seagrasses differ from other halophytes in several ways: they are the only plants, living entirely underwater except during rare, very low tides they have no means of extracting fresh water from seawater they extract oxygen from the seawater and have internal air canals they do not need to have a freshwater source because they have an internal salinity the same as seawater they reproduce by releasing pollen into the water, much like land-based plants release pollen into the wind Coastal Ecosystems >

Seagrasses seagrasses differ from other halophyte-based ecosystems because: they are edible and provide food for ecosystem inhabitants like microbes, invertebrates, fish, turtles, manatees, and dugongs Coastal Ecosystems >

Intertidal Zones the area between the high tide mark and the low tide mark ecosystems in the intertidal zones exist in areas that may be above the waterline at times other portions reach depths of 10 meters (32.8 feet) supralittoral zone the area only submerged during the highest tides the greatest challenges facing organisms that live in this zone are drying out, thermal stress, and water motion with the constant spray of seawater evaporating, high salt levels can also be a problem Coastal Ecosystems >

Intertidal Zones littoral zone the area between high and low tide the organisms here must also deal with drying out, thermal stress, and water motion with ample water nutrients, and sunlight, this is a highly productive region. one challenge to life here, therefore is massive competition Coastal Ecosystems http://www.youtube.com/watch?v=IyNEG-PvZmM&safety_mode=true&persist_safety_mode=1&safe=active >

Pelagic Oceanic Neritic Photic Dysphotic Aphotic Benthic Abyssal

Neuston Ecosystems neuston – plankton that live afloat on the surface make up an ecosystem a few millimeters thick despite being thin, this forms a major ecosystem receiving maximum sunlight and covering about 71% of the Earth’s surface cyanophyte, diatom and dinoflagellate populations – may be 10,000 times more numerous here than in the water just a few millimeters deeper Ecosystems in the Open Sea >

Neuston Ecosystems The world’s largest floating ecosystem In some areas photosynthesis and primary productivity are higher below the neuston ecosystem. This may be due to: a. photoinhibition the condition in which excess light overwhelms an autotroph’s ability to photosynthesize prevalent in tropical seas ; possible cause – - UV light gets though because there’s little water to protect neuston organisms b. or possibly due to pollutants a concern to scientists with respect to global warming. pollutants concentrate in the neuston layers, just like beneficial nutrients The world’s largest floating ecosystem is the Sargasso Sea in the middle of the North Atlantic gyre. Ecosystems in the Open Sea >