Env Ch 16a

  1. Currents
    • •the ocean is composed of vast riverlike flows
    • -Driven by density differences, heating and cooling, gravity, and wind
    • -Influence global climate and El Niño and La Niña
    • -Transport heat, nutrients, pollution, and the larvae of many marine species
  2. Upwelling
    • the vertical flow of cold, deep water towards the surface
    • -High primary productivity and lucrative fisheries
    • -Also occurs where strong winds blow away from, or parallel to, coastlines
  3. Mangroves
    • trees with unique roots
    • -Curve upwards for oxygen
    • -Curve downwards for support
  4. People and Mangroves
    • Development for residential, commercial, and recreational uses
    • Shrimp farming
    • Half the world’s mangrove forests are gone
    • Once destroyed, coastal areas no longer
    • Slow runoff
    • Filter pollutants
    • Retain soil
    • Protect communities against storm surges
    • We are protecting only 1% of remaining mangroves
  5. Estuaries
    water bodies where rivers flow into the ocean

    • Wide fluctuations in salinity
    • Critical habitat for shorebirds and shellfish
    • Transitional zone for anadromous (spawn in freshwater, mature in salt water) fishes
    • Affected by development, pollution, habitat alteration, and overfishing
  6. Oceans provide transportation
    Moving people and products over vast distances

    Accelerated global reach of cultures
  7. Energy from oceans
    Crude oil and natural gas

    -Oil spills damage fisheries
  8. Methane Hydrate
    • a potential energy source
    • Ice-like solid methane embedded in water crystals
    • A vast supply, but research needs to be done
  9. We extract minerals from oceans
    • sand, gravel, sulfur, calcium carbonate, and silica
    • copper, zinc, silver, and gold
  10. Marine Pollutions
    • •Even into the mid-20th century, coastal U.S. cities dumped trash and untreated sewage along their shores
    • •Oil, plastic, chemicals, excess nutrients make their way from land into oceans
    • •Raw sewage and trash from cruise ships
    • •Abandoned fishing gear from fishing boats
  11. Plastic and Marine Life
    • Plastic items dumped into the sea harm or kill wildlife
    • Plastic is non-biodegradable
    • Drifts for decades
    • Washes up on beaches
    • Wildlife eat it or get entangled and die
  12. Harmful Algae blooms
    nutrients increase populations of algae that produce powerful toxins
  13. Red Tide
    algal species produce reddish pigments that discolor water

    • Illness and death to wildlife and humans
    • Economic losses to fishing industries and beach tourism
  14. Marine Protected Areas (MPA)
    established along the coastlines of developed countries

    -Still allow fishing or other extractive activities
  15. Marine Reserves
    • areas where fishing is prohibited
    • -Leave ecosystems intact, without human interference
    • -Improve fisheries, because young fish will disperse into surrounding areas
Card Set
Env Ch 16a