1. Aquatic Ecosystems
Chapter 7

2. Key Vocabulary WETLAND- an area where land is periodically under water
PLANKTON-organisms that float near the top or surface of water, two types:phytoplankton (microscopic plants) and zooplankton (microscopic animals)
NEKTON- free swimming organisms like fish, turtles, and whales
BENTHOS- bottom dwelling organisms such as mussels, worms and barnacles

3. LITTORAL ZONE- area near the shore of fresh water, nutrient rich, and abundant and diverse aquatic life
BENTHIC ZONE- bottom area of a pond or lake in fresh water, includes decomposers, insect larvae and clams
EUTROPHICATION- an increase in the amount of nutrients in an aquatic ecosystem, associated with a lot of plant life

4. ESTUARY- an area where fresh water from a river mixes with salt water from an ocean
SALT MARSH- develop in estuaries where rivers deposit mineral rich mud
MANGROVE SWAMP-swamps located along coastal areas of tropical and subtropical zones
BARRIER ISLANDS- long, thin islands that run parallel to the shore
CORAL REEFS- limestone ridges built by coral animals called coral polyps which secrete calcium carbonate, home to many different plants and animals

5. Freshwater Ecosystems
Objectives 1-4

6. 1. What factors determine where an organism lives in an aquatic ecosystem?
the types of organisms that live in aquatic systems is determined by the salinity of the water- amount of dissolved salts in the water
determining factors include temp., sunlight oxygen, and nutrients
types of organisms include plankton (plant and animal), nekton ( free swimmers), and benthos ( bottom dwellers)

7. Freshwater Ecosystems
LAKES
PONDS
RIVERS
WETLANDS
STREAMS

8. 2. Littoral vs. Benthic Zones
lakes and ponds are divided into different zones

9. Littoral Zones nutrient rich near the shore
contains rooted plants underwater with leaves emerged above water, floating leaves, submerged plants, algae, and bacteria
types of organisms present depends on amount of sunlight

10. BENTHIC ZONE
bottom area of lake or pond consisting of decomposers, larvae of insects, and clams

11. Freshwater Wetlands areas of land covered by water for part of a year
2 types: marshes that contain nonwoody plants and swamps that contain woody plants

12. 3. Importance of Freshwater Wetlands, see table 1 pg. 175
1.serve as filters or sponges, absorbing and filtering pollutants which increases water quality
2. control flooding by absorbing extra water
3. serve as feeding and spawning ground for fish
4. provide habitats for wildlife & traps carbon
6.used to produce commercial products

13. Marshes
most U.S marshes in southeast , Florida Everglades is the larges U.S. marsh
occur on low flat land with little water movement
nutrient rich bottom sediment good for plants
marsh types characterized by salinity (brackish vs. salt)

14. Swamps occur on flat, poorly drained land, commonly near streams
woody shrubs or water loving trees
mangrove swamps (salty) and freshwater swamps
fresh provide habitat for amphibians, waterfowl, and reptiles

15. Human Impact on Wetlands
once considered wastelands
many have been drained, filled or cleared for farming and residential development
protected by government b/c of importance as habitats, purifiers , and flood prevention

16. RIVERS many rivers originate from snow melt from mountains
headwaters cold & full of oxygen, running swiftly
as river flows downward, it can widen, get warmer, slower, and decrease in oxygen
changes with land and climate
river location & characteristics determine life that lives there

17. 4. RIVERS IN DANGER
industries use river water for manufacturing and for waste deposits
people have used rivers for sewage and garbage
these uses lead to pollution that kills and makes fish in edible
run off from land puts pesticides and poisons into rivers
dams also alter ecosystems

18. Marine Ecosystems
-Coastal Wetlands
-Oceans

19. Coastal Wetlands include estuaries and coral reefs
provide habitats and nesting areas for fish and wildlife
absorb excess rain from flooding, filter pollutants, provide recreational areas

20. Estuaries
area where fresh water from river mixes with salt water from ocean
include horseshoe crabs, variety of plants, dolphin, manatee, seals, oysters, barnacles ( organisms must be able to tolerate variation in salinity)
major ports are built on estuaries, why?
threats include wastes from sewage, industrial waste with toxic chemicals, and agricultural run off

21. 5. Why is an estuary a productive ecosystem?
They constantly receive nutrients from rivers and oceans
see page 179

22. 6. Salt water marshes vs. mangrove swamps...
salt marshes are dominated by marsh grasses and develop in estuaries, common along Gulf of Mexico & Atlantic. coast
mangrove swamps are dominated by mangrove trees and develop in tropical and subtropical areas, dominated by salt tolerant trees

23. Rocky and Sandy Shores
Barrier Reefs-long thin island runs parallel to shore, protect mainland and coastal wetlands
rock shores have more species, why?

24. Coral Reefs live in clear, warm, shallow salt water
limestone ridges built by coral polyps
home to thousands of species of plants and animals

25. 7. Factors that can damage coral reefs...
water that is too cold or too hot can kill coral reefs
muddy waters kill algae or promote growth uncontrollably
human activities endanger 27% of reefs
oil spills, sewage, pesticides, silt run off destruct reefs
overfishing can disturb ecosystem balance

26. Plants and Animals of Oceans
Phytoplankton grow where there’s light for photosynthesis
Zooplankton that feed on phytoplankton, include jellyfish, tiny shrimp, fish larvae
Decomposers, filter feeders and organisms that feed on dead matter live in the bottom

27. 8. How are animals of oceans threatened?
pollution from land activities ( run off from agriculture creates algal blooms), industrial wastes, sewage discharge
overfishing and fishing methods are destroying fish populations

28. Arctic & Antarctic Ecosystems
located at north and south poles
Depend on marine life for food
Supports plankton and huge diversity of fish
Arctic rich in nutrients from surrounding landmasses
Antarctic has never been colonized by humans