Wetlands and El Nino

• Earth's Temperature changes with Seasons
• Earth's inclination on axis is always the same
• The Atmosphere protects Earth's surface from harmful radiation
• The Atmosphere keeps the planet warm
• The Atmosphere produces climate
• The Atmosphere Conveyor Belt
• Interaction between Sea and atmosphere
• Driving Forces for Ocean Currents:

  • Ocean Temperatures
  • Winds
  • Position of the Continents
  • Coriolis Effect
• In the Northern Hemisphere, Ocean Currents move clockwise

  In the Southern Hemisphere, Ocean Currents move counterclockwise
• EL Nino occurs every 3 to 7 years
• EL Nino originates in the western equatorial Pacific Ocean
• The exact cause of the phenomena of EL Nino is unknown
• During an ENSO event, winds and currents in the Equatorial Pacific Ocean weaken or even reverse, resulting in large-scale climatic changes throughout the Pacific
• During an EL Nino event, a pool of warm surface water migrates from the tropical Pacific to the eastern Pacific coast (Americas) due to reduction in trade winds

  A cold water mass moves towards the coast of Asia (opposite of what occurs in a non-ENSO year)
• Impacts of EL Nino include:

  • Eastern Pacific (North & South America) experiences increased storms and lower bioproductivity in coastal waters
  • Western Pacific (Asia) experiences droughts and extreme wildfires
• Kelp Forests in temperate near-shore waters below 72°F with clear water and seasonal upwelling
• Kelp Forest Layers depend on nutrient-rich upwelling and are the base of coastal ecosystems

  During an EL Nino event, kelp dies, and the ecosystem declines
• EL Nino prevents Coastal Upwelling
• Weather impacts of EL Nino include:

  • California experiences massive floods, mudslides, and bridge damage
  • South America experiences massive floods, mudslides, and fisheries collapse
  • South Pacific experiences typhoons and coral bleaching
• Biological Impacts of El Nino include:

  • Upwelling is blocked, leading to loss of bio productivity (Fish Stocks)
  • Coral Bleaching occurs, resulting in loss of bio productivity and diversity
  • Storms lead to more standing water, higher vector populations, and West Nile Virus in California
  • Droughts cause forest fires, loss of habitat, and may force disease-causing vector populations to come in contact with humans
• Wetlands are important biomes in the APES course because they intersect aquatic, marine, and terrestrial biomes, offering unique opportunities to understand ecological interactions between distinct but interconnected biological communities
• Wetlands provide numerous ecosystem services to human societies and have historically been under threat from human development
• A wetland is land that is wet for a certain portion of the year and generally contains specific types of plants adapted to being submerged in water for extended periods
• Types of wetlands:

  • Marshes in mountainous areas with a rich diversity of aquatic wildlife like trout, frogs, and aquatic insects
  • Everglades (Swamps) found in subtropical locations like Florida and the Southeast U.S., which are vast areas of flat land saturated with water
  • Coastal estuaries in tropical and temperate latitudes, known as estuaries in temperate latitudes and mangrove forests in tropical latitudes
• The Everglades of Florida have been altered due to humans altering water flows to control floods for urban development and releasing invasive species like Pythons
• Coastal estuaries are influenced by the hourly fluctuation of tides, with two high tides during the day bringing in saltwater from the ocean and changing the temperature, depth, and salinity of the estuary
• Rivers influence the abiotic factors of wetlands by carrying sediments that are deposited in wetlands, making them shallow and nutrient-rich. Tides influence the abiotic factors by causing hourly variations in depth, salinity, and temperature
• The relationship between depth of water and temperature is that shallow water during low tides increases water temperature
• The biggest problem for fish or other marine organisms in estuaries during low tide is the decrease in water depth, which can lead to increased water temperature and decreased salinity
• If sea levels rose due to climate change, the abiotic factors of wetlands would be different with potentially increased salinity and changes in water depth
• Coastal estuaries are considered eutrophic due to being nutrient-rich, which influences the Net Primary Productivity (NPP) of estuaries by supporting high levels of phytoplankton and terrestrial plants
• Eutrophication does not lead to loss of dissolved oxygen in coastal wetlands because the nutrient-rich environment supports abundant plant growth that produces oxygen
• Ecosystem services of coastal estuaries include:

  Supportive:

  • High NPP and abundance of life supporting both terrestrial and marine food webs
  • Rest stops for migratory birds along flyways
  • Nurseries for coastal marine fish species
• Regulatory ecosystem services of wetlands include flood control and buffers from storm surges, and filtration (bio-filtration) to trap sediments and remove organic material from water before it can decompose
• Anthropogenic threats to coastal estuaries:

  • Almost 80% of coastal estuaries worldwide have been lost to human activities
  • Coastal estuaries are under constant threat of development
  • Historically, coastal estuaries were converted to farmlands
  • Coastal estuaries have been developed as ports and marinas
  • Demand for beachfront housing is the largest threat to coastal wetlands
  • Wetlands are drained for housing due to limited and valuable coastal property
  • U.S. law states "There can be no net loss of wetlands in U.S."
• One additional threat to the ecology of coastal wetlands is the construction of dams along the rivers flowing into them
• Ecological impact of dams on coastal estuaries:

  • Dams disrupt the natural flow of rivers into coastal estuaries
  • This disrupts the nutrient input and sediment flow into the estuaries
  • Altered nutrient input can affect the productivity and biodiversity of the estuarine ecosystem
• Abiotic factors that make wetlands ideal farmland:

  • Wetlands have nutrient-rich soil
  • Wetlands receive constant input of fresh water
  • The topography of wetlands makes them suitable for agriculture
• Physical changes in the Pacific Ocean during an ENSO event:

  • Ocean currents flow from the equator up towards the poles
  • Warm ocean currents flow up from the equator along the coast of Asia and cool as they reach the Arctic
  • Cold ocean currents return to the equator along the coast of California
  • During an ENSO event, trade winds weaken, causing a pool of warm water along the coast of California and cooler water along the coast of Asia
• Terrestrial biome impacts of ENSO:

  • Ocean temperatures along coastlines influence annual rainfall patterns on land
  • During an ENSO event, coastal California and South America experience intense rainfall, while Asia experiences severe droughts and fires