KEY CONCEPT Marine ecosystems are global.

1. KEY CONCEPT Marine ecosystems are global.

2. intertidal zone neritic zone bathmatzone abyssalzone The ocean can be divided into zones. • Ocean zones can be determined by their distance from shoreline and water depths. • intertidal zone—between low and high tide • neritic zone—from intertidal zone to edge of continental shelf (up to 200 m deep) • bathyal zone—from neritic zone to base of continental shelf (from 200 to 2000 m) • abyssal zone –lies below 2000 m and is in complete darkness

3. Plankton make up most of the biomass. Tiny free floating organisms (animals and protists). • Zooplankton (animal plankton) • Phytoplankton (photosynthetic plankton) • Critical to life on the planet because they carry out the bulk of photosynthesis on Earth, which means they provide most of the oxygen. • Base of the oceanic food web. • The neritic zone harbors more biomass than any other zone.

4. The intertidal zone is inhabited by organisms that must be tolerant of a variety of conditions that result from the changing of water levels. • Must be able to deal with change in temperature, amount of moisture and salinity. • Sea anemone: opens up when under water and closes during low tide to avoid drying out.

5. In the Bathyal zone you will find organisms such as fish that have adapted to living in areas of high pressure. • - Burrowing animals can also be found thriving in this zone. • The abyssal zone has a much smaller number of species. • There is no light, photosynthetic organisms do not exist down there. • Chemosynthetic organisms are the base of the food web. • Many organisms that live here make their own light which is often used to attract a mate and/or prey.

6. Coastal waters contain unique habitats. • Coral reefs are found in warm waters within the nertic zone. • tropical climate zone • great amount of biomass • Corals are animals that have a mutualistic relationship with algae (provide nutrients). • A change in temperature or pollution can kill the algae, which then starves the coral.

7. Kelp forests are found in cold, nutrient-rich waters. • large communities of seaweed • great amount of biomass • Can reach over 30 m. • Area of high productivity • Provides habitat and food sources for many marine animals.

8. KEY CONCEPT Freshwater ecosystems include estuaries as well as flowing and standing water.

9. Estuaries are dynamic environments where rivers flow into the ocean. • An estuary is a partially enclosed body of water. • mixture of fresh water with salt water • Chesapeake Bay • Louisiana bayous

10. Estuaries provide a protected refuge for many species: • Ex: photo. Org., decomposers, phyto and zooplankton • It provides a stop point for migratory birds • spawning grounds for fish • Estuaries are primarily threatened by land development. • In the United states, 80% of the original estuary habitat has been lost to land development. • Estuaries are highly productive ecosystems.

11. Freshwater ecosystems include moving and standing water. • A watershed is a region of land that drains into a body of water.

12. Little flowing water – “standing water” • provide a home for many species • filters dirty water • renew underground water supply • Some animals have adaptations suited to the freshwater they inhabit. • ex:streamlined bodies, hooks and suckers are found on many river organisms. • Wetlands are among the most productive ecosystems.

13. Ponds and lakes share common features. • Freshwater bodies are divided into three zones. • littoral zone: located between the high and low water marks along the shoreline (water lilies, dragonflies, snails) • limnetic zone: Open water located farther out from shore (plankton communities, fish) • benthic zone: lake or pond bottom, where less sunlight reaches (decomposers)

14. Turn over happens due to changes in density. • Most dense at 4 degrees C (39 degrees F) • In both autumn and spring, surface water flows downward and bottom water flows upward. • The upwelling brings up nutrients. • All lakes “turn over” periodically.