Aquatic Ecosystems

1
Aquatic Ecosystems
2
Introduction

• Ecosystem - collection of all organisms living
  within their environment.
• Aquatic ecosystems centered around water and the
  organisms who inhabit these ecosystems are
  specifically adapted for such survival.

3
The Hydrosphere

• The Earth is divided into different spheres.
• Hydrosphere relates to the entire mass of water
  on the planet.
• Biosphere includes all living things including
  life on land, in water, and in air.
• The organisms within the biosphere interact
  closely with the hydrosphere for survival.

4
Streams and Rivers

• A river is a stream of moving water that follows
  a definite course.
• Creek, brook, stream, and river quality is
  directly related to the health of other bodies of
  water, as these moving bodies of water drain into
  larger lakes and some eventually lead to oceans.
• These environments are characterized by higher
  levels of oxygen (due to the waters movement) and
  little plant life until the speed of the river
  slows.

5
Streams and Rivers

• Recent EPA findings (summarized below) show that
  the health of the nations streams is poor
• polluted with phosphorous and nitrogen
• with nearby land disturbed by pipes, pastures, or
  pavement.

6
Freshwater Lakes Ponds

• A lake is a body of water of considerable size
  surrounded by land.
• The EPA states that freshwater inland lakes and
  reservoirs provide our nation with 70 of its
  drinking water and supply water for industry,
  irrigation, and hydropower.
• Lake ecosystems support complex food web
  interactions and provide habitat for threatened
  and endangered species.
• The United States has a 19 billion dollar
  freshwater fishing industry dependent on the
  health of lakes, and many states tourism
  industry centers rely on these freshwater
  reservoirs.
• Video Cleaning Lake Tahoe

7
Wetlands

• Wetlands are characterized by regular saturation
  of the soil either totally covering the soil or
  is present at or near the surface for at least
  part of the year.
• They are found on every continent except
  Antarctica.
• They can include swamps, bogs, and marshes and
  can be fresh, salty or brackish (a mixture of
  fresh and salt water).
• (Video - Wetland Conservation)

http//www.tpwd.state.tx.us/learning/webcasts/seac
enter/images/txhab/wet-types.jpg
8
Estuary

• Wetlands formed where rivers meet the sea are
  known as estuaries, a combination of fresh and
  salt water (brackish water).
• A delta is the fanned build up of sediment from
  river deposits which often covers the center of
  the estuary.

http//www.texasep.org/assets/images/estuary2.GIF
9
Relationships Between Pollutants Aquatic
Environments
http//www.epa.gov/owow/oceans/nccr3/pdf/nccr3_ent
ire.pdf
10
Marshes

• Marshes - wetlands frequently or continually
  flooded with water, with soft-stemmed vegetation.
  
• Can be fresh or salt water.
• Nutrients are plentiful leading to an abundance
  of plant and animal life.
• Marshes recharge groundwater supplies, help to
  limit damage from flooding and coastal storms,
  and most importantly, clean the water of
  pollutants.
• As water moves slowly through a marsh, sediment
  and other pollutants settle to the floor of the
  marsh.

11
Swamps

• Swamps are wetlands characterized by woody plants
  with water soaked soils during the growing
  seasons and standing water at times.
• The soils are thick, black, nutrient-rich and
  grow water-tolerant trees such as Cypress,
  Atlantic White Cedar, and Tupelo.

http//www.nwrc.usgs.gov/factshts/2004-3019/images
/figure4.gif

• Plants, birds, fish, and invertebrates such as
  freshwater shrimp, crayfish, and clams require
  the habitats provided by swamps.
• Many rare species, such as the endangered
  American Crocodile depend on these ecosystems as
  well.
• (Video American Crocodiles)

12
Texas Swamps

• Caddo Lake State Park
• the only natural lake in Texas
• created by a mass of trees and flood debris known
  historically as the Great Raft of the Red River.
  It obstructed the river channel for more than 100
  miles above Shreveport, Louisiana until 1874,
  when it was successfully removed to
• clear the channel for
• navigation.
• lake slowly drained away,
• leaving a swamp
• - A modern dam has
• recreated the lake

13
Mangrove Swamps

• Characterized by salt-tolerant evergreen trees
• protect coastlines from erosion, filter
  pollutants from the water and are home and food
  for a variety of organisms.
• Some have aerial roots that collect oxygen not
  available in the mud. Some excrete salt in their
  leaves.
• Ex The famous Florida Everglades
• (Video Save the Everglades)

http//www.fao.org/forestry/4185-1-0.jpg
14
Seagrass Beds

• Another source of food and protection for aquatic
  organisms living near the coast
• fully marine flowering plants
• grow best in shallow bays and lagoons
• very susceptible to pollution
• important food source for aquatic turtles,
  manatees, dugongs, and other marine herbivores
• Salt Marsh Video

http//baysoundings.com/Spring08/Stories-Images/Se
agrass-Graph-black_white.jpg
http//www.thalabeach.com.au/blog/wp-content/uploa
ds/2009/10/dugong.jpg
15
Kelp Forest

• common name for brown seaweed, a type of algae
  that is photosynthetic
• Kelp forests grows in cold water and certain
  species can grow to reach 265 feet!
• gas floats on the surface, allowing access to
  sunlight
• Unlike seagrass, kelp does not have root systems

Photograph by Frans Lanting
16
Lagoons Fjords

• Fjords - deep, sheltered seas created by ancient,
  glacial erosion, often bordered by steep cliffs
• Lagoons - partially enclosed body of sea water
• Both areas are characterized by slower moving
  waters protected from the strong currents of the
  coast.