I.Marine Ecosystems

A.Saltwater ecosystems found near coastal areas

B.COASTAL WETLANDS

i.Land covered by salt water for all or part of the year

ii.Helps to...

a)Absorb excess rain

b)Prevent flooding

c)Filter pollutants

d)Create recreation areas

iii.ESTUARIES

a)River fresh water & ocean salt water mix

b)Mixing of water creates nutrient trap, holding nutrients in soil

  • Very good for producers in shallow areas
  • Surrounding land creates protective area from ocean waves

c)Plants & Animals

  • Light for photosynthesis w/lots of soil nutrients
  • Support lrg. pop. of plants & plankton
  • Plankton & plants → small fish → Dolphins, manatees, seals
  • Plankton → filter feeders (oysters, barnacles, clams)

d)Many major harbors built on estuaries

  • Tokyo, New York, Shanghai, New Orleans

e)Threats

  • Used as a place to dump waste
  • Sites then filled in and developed on

iv.SALT MARSHES

a)Estuary that develops large grasses & non-woody plants

b)Nursery for development of shrimp, crab, fish, & aquatic birds

  • Protection while young

c)Absorbs pollutants & prevent flooding

v.MANGROVE SWAMP

a)Saltwater wetland with wood-plants

b)Dominated by Mangrove trees

  • Trees grow partially submerged in shallow saltwater

c)Helps to protect shoreline from erosion & storm damage

d)Breeding ground for thousands of species

e)Threatened by human dumping and development

C.CORAL REEFS

i.Limestone ridges built by tiny coral animals called CORAL POLYPS

a)Leaves behind skeleton of limestone, forming reefs

b)Outer layer of reef contains living polyps

ii.One of most diverse ecosystems on earth

iii.Only form in warm, clear, shallow saltwater

a) Allows light for photosynthesis

iv.Threats

a)Very fragile & sensitive to pollution, clarity & temp changes

b)27% of reefs are endangered

c)Grows very slowly and may not regenerate fast enough to support ecosystem

D.OCEANS

i.
Sunlight

a)Only travels though approx 330ft

  • Limits photosynthetic area that supports life

b)Plants & Animals

  • Depend on layer of ocean
  • OCEAN SURFACE
  • Home for many org.
  • phytoplankton, jellyfish, shrimp, fish-oyster-lobster larvae
  • Light penetrates this layer
  • SHALLOW WATERS
  • Coastal zones provide rich nutrients from land for many org
  • Light penetrates this layer
  • DEEP WATERS
  • Perpetually dark
  • B/c lack of sunlight, no photosynthesis
  • Most org depend of food that drifts from higher layers

ii.Threats

a)Pollutants

  • Nutrient runoff
  • Industrial waste / sewage

b)Overfishing

c)Illegal hunting of animals