Aquatic Biomes Chapter 7

Aquatic Ecosystems  Characteristics of aquatic ecosystems –Salinity –Temperature –Sunlight –Oxygen –Nutrients

Aquatic Ecosystems  Types of organisms –Plankton- organisms that float near the surface  Phytoplankton- photosynthetic  Zooplankton- heterotrophic –Nekton- free swimming organisms  Fish, turtles, whales –Benthos- bottom dwelling organisms  Mussels, worms, barnacles

Freshwater  Ponds and Lakes –Life in a lake  Littoral zone- nutrient rich area near the shore –Life is abundant  Benthic zone- bottom of a pond or lake –Dead and decaying organisms are found here –Nutrients in a lake  Eutrophication- increase in the amount of nutrients in a lake or pond –Algal bloom

Freshwater

Freshwater  Wetlands- areas saturated with water during part of the year (growing season)

Freshwater  Wetlands

Freshwater –Marshes-  low, flat lands with little or no water movement  Dominated by non-woody plants  Bethic zone is very nutrient rich  Characterized by salinity –Brackish marsh- slightly salty water –Saltwater marsh- contains salty water

Freshwater  Swamps –Flat, poorly drained land, often near streams –Dominated by woody plants (trees and shrubs) –Types determined by lattitude and climate  Mangrove swamp- warm climate, salty water

Freshwater  Human impact on Wetlands –Drained, filled, and cleared for farms, residential, or commercial uses  Ex: Florida everglades covered 8 million acres in south florida but today cover less than 2 million. –Today, protected by federal, state, and local laws.

Freshwater  Rivers and streams –Headwaters- usually cold, rapidly moving water at high elevation.  High oxygen levels –Lower Channel- warmer, slower moving water  lower oxygen levels –Delta- where the river meets a gulf, ocean, or sea

Freshwater  River or streams –Life in a river  Headwaters- mosses, trout, minnows  Lower Channel- plankton, fish, turtles, snakes, alligators

Marine Ecosystems  Coastal wetlands –Estuaries  An area in which freshwater from a river mixesw with salt water from the ocean  Very productive ecosystem  Fresh nutrients enter from both the river and ocean  Area protected from harsh ocean waves because of land forms like a peninsula

Marine Ecosystem  Estuaries

Marine Ecosystem  Estuaries –Plants  Many rooted plants and plankton –Animals  Many ocean dwelling animals move into estuaries to lay eggs –Threats  Urban growth  pollution

Marine Ecosystems  Coastal wetlands –Salt marsh –Mangrove swamps –Rocky and Sandy beaches  Barrier islands- run parallel to the shore and protect it from the ocean

Marine Ecosystems  Coral Reefs –Built by of the limestone exoskeletons of coral polyps –Occur in warm, shallow seas –Very biodiverse –Threats  Human activities  Water temperature change  Fresh water intrusion  pollution

Marine Ecosystem  Coral Reefs

Marine Ecosystems  Oceans –Much of the life is concentrated in the shallow (less than 100m) warm water near the shore –Deep ocean water is very unproductive because of a lack of light and nutrients –Threats  Pollution  Overfishing –Artic and Antarctic ecosystems depend of the ocean ecosystem for survival

Marine Ecosystem  Ocean