Chapter 8: Aquatic Biodiversity
Coral Reefs
Ecological & Economic Services
Moderate atmospheric temperatures
Act as natural barriers protecting coasts from erosion
Provide habitats
Support fishing and tourism businesses
Provide jobs and building materials
Studied and enjoyed
Degradation and Decline
Coastal development
Pollution
Overfishing
Warmer ocean temperatures leading to coral bleaching→ Kill algae and thus the polyps
Increasing ocean acidity
What Is the General Nature of Aquatic Systems?
Most of the Earth Is Covered with Water
Saltwater includes;
Atlantic
Pacific
Arctic
Indian
Freshwater: Any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids.
Aquatic Life Zones
Saltwater life zones (marine life zones): Oceans, estuaries, coastlands, shorelines, coral reefs, and mangrove forests.
Freshwater life zones: Lakes, rivers, streams, and inland wetlands
Aquatic Species
Plankton→ Free floating creatures
Phytoplankton: Primary producers for most aquatic food webs
Zooplankton: Primary and secondary consumers. Single-celled to large invertebrates like jellyfish
Ultraplankton: Tiny photosynthetic bacteria
Nekton are strong swimmers
Fish, turtles, whales, etc.
Benthos: Bottom dwellers
Oysters, sea stars, clams, lobsters, crabs, etc.
Decomposers: Mostly bacteria
Key Factors That Determine Types & Numbers of Organisms
Critical factors in the distribution of organisms
Temperature
Dissolved oxygen content
Availability of food
Availability of light and nutrients needed for photosynthesis in the eutrophic (photic) zone
Turbidity: Degree of cloudiness in the water, inhibits photosynthesis
Why Are Marine Aquatic Systems Important?
Oceans Provide Vital Ecological and Economic Resources
Reservoirs of diversity in three major life zones
Coastal zone: Warm, nutrient-rich, shallow. Shore to the edge of a continent shelf.
Open sea
Ocean bottom
Major Ecological and Economic Services Provided by Marine Systems
Ecological Services
Climate moderation
CO2 absorption
Nutrient cycling
Waste treatment
Reduced storm impact (mangroves, barrier islands, coastal wetlands
Habitats and nursery areas
Genetic Resources and biodiversity
Scientific information
Economic Services
Food
Animals and pet feed
Pharmaceuticals
Harbors and transportation routes
Coastal habitats for humans
Recreation
Employment
Oil and natural gas
Minerals
Building materials
Estuaries and Coastal Wetlands
Estuaries/Coastal Wetlands: Where rivers meet the sea and seawater mixes with freshwater (ex. river mouths, inlets, bays, sounds, salt marshes, and mangrove forests.)
Very productive ecosystems→ high nutrient levels
Seagrass Beds: Grow underwater in shallow areas, support a variety of marine species, stabilize shorelines, and reduce wave impact.
Mangrove forests: Along tropical and subtropical coastlines, 69 different tree species grow in saltwater
Rocky and Sandy Shores Host Different Types of Organisms
Intertidal zone: Rocky shores or sandy shores which have barrier beaches
Three Zones of the Ocean
Euphotic zone: Phytoplankton, nutrient level low, dissolved oxygen levels high.
Bathyal zone: Dimly lit, zooplankton and smaller fishes
Abyssal zone: Dark and cold, high levels of nutrients, little dissolved oxygen, deposit feeders, filter feeders
How Have Human Activities Affected Marine Ecosystems?
Major threats to marine systems
Major threats to marine systems
Coastal development
Overfishing
Use of fishing trawlers
Runoff of nonpoint source pollution
Point source pollution: Discharge pollutants at specific locations
Habitat destruction
Introduction of invasive species
Climate change from human activities
Pollution of coastal wetlands and estuaries
Why Are Freshwater Ecosystems Important?
Water Stands in Some Freshwater Systems and Flows in Others
Standing (lentic) bodies of freshwater: Lakes, ponds, inland wetlant=ds
Flowing (lotic) systems of freshwater: Streams and rivers
Littoral zone: Near shore where rooted plants grow, high biodiversity,
Turtles, frogs, crayfish, and some fish
Limnetic zone: Sunlight area away from shore, main photosynthetic zone, some larger fish
Profundal zone: Deepwater too dark for photosynthesis, low oxygen levels, with some fish
Benthic zone: Decomposers, detritus feeders, and some fish, nourished primarily by dead matter
Major Services Provided by Freshwater Systems
Ecological Services:
Climate moderation
Nutrient cycling
Waste treatment
Flood control
Groundwater recharge
Habitats for many species
Genetic resources and biodiversity
Scientific information
Economic Services:
Food
Drinking water
Irrigation water
Hydroelectricity
Transportation corridors
Recreation
Employment
Some Lakes Have More Nutrients Than Others
Oligotrophic Lakes: Low levels of nutrients and low NPP with very clear water
Eutrophic Lakes: High levels of nutrients and high NPP and murky water with high turbidity
Mesotrophic Lakes: Commonly clear water lakes and ponds with beds of submerged aquatic plants and medium levels of nutrients
Cultural Eutrophication: This occurs when sewage, detergents, fertilizers, and other nutrient sources are introduced into the ecosystem as a result of human water pollution, accelerating the aging process.
Chapter 8: Aquatic Biodiversity
Coral Reefs
Ecological & Economic Services
Moderate atmospheric temperatures
Act as natural barriers protecting coasts from erosion
Provide habitats
Support fishing and tourism businesses
Provide jobs and building materials
Studied and enjoyed
Degradation and Decline
Coastal development
Pollution
Overfishing
Warmer ocean temperatures leading to coral bleaching→ Kill algae and thus the polyps
Increasing ocean acidity
What Is the General Nature of Aquatic Systems?
Most of the Earth Is Covered with Water
Saltwater includes;
Atlantic
Pacific
Arctic
Indian
Freshwater: Any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids.
Aquatic Life Zones
Saltwater life zones (marine life zones): Oceans, estuaries, coastlands, shorelines, coral reefs, and mangrove forests.
Freshwater life zones: Lakes, rivers, streams, and inland wetlands
Aquatic Species
Plankton→ Free floating creatures
Phytoplankton: Primary producers for most aquatic food webs
Zooplankton: Primary and secondary consumers. Single-celled to large invertebrates like jellyfish
Ultraplankton: Tiny photosynthetic bacteria
Nekton are strong swimmers
Fish, turtles, whales, etc.
Benthos: Bottom dwellers
Oysters, sea stars, clams, lobsters, crabs, etc.
Decomposers: Mostly bacteria
Key Factors That Determine Types & Numbers of Organisms
Critical factors in the distribution of organisms
Temperature
Dissolved oxygen content
Availability of food
Availability of light and nutrients needed for photosynthesis in the eutrophic (photic) zone
Turbidity: Degree of cloudiness in the water, inhibits photosynthesis
Why Are Marine Aquatic Systems Important?
Oceans Provide Vital Ecological and Economic Resources
Reservoirs of diversity in three major life zones
Coastal zone: Warm, nutrient-rich, shallow. Shore to the edge of a continent shelf.
Open sea
Ocean bottom
Major Ecological and Economic Services Provided by Marine Systems
Ecological Services
Climate moderation
CO2 absorption
Nutrient cycling
Waste treatment
Reduced storm impact (mangroves, barrier islands, coastal wetlands
Habitats and nursery areas
Genetic Resources and biodiversity
Scientific information
Economic Services
Food
Animals and pet feed
Pharmaceuticals
Harbors and transportation routes
Coastal habitats for humans
Recreation
Employment
Oil and natural gas
Minerals
Building materials
Estuaries and Coastal Wetlands
Estuaries/Coastal Wetlands: Where rivers meet the sea and seawater mixes with freshwater (ex. river mouths, inlets, bays, sounds, salt marshes, and mangrove forests.)
Very productive ecosystems→ high nutrient levels
Seagrass Beds: Grow underwater in shallow areas, support a variety of marine species, stabilize shorelines, and reduce wave impact.
Mangrove forests: Along tropical and subtropical coastlines, 69 different tree species grow in saltwater
Rocky and Sandy Shores Host Different Types of Organisms
Intertidal zone: Rocky shores or sandy shores which have barrier beaches
Three Zones of the Ocean
Euphotic zone: Phytoplankton, nutrient level low, dissolved oxygen levels high.
Bathyal zone: Dimly lit, zooplankton and smaller fishes
Abyssal zone: Dark and cold, high levels of nutrients, little dissolved oxygen, deposit feeders, filter feeders
How Have Human Activities Affected Marine Ecosystems?
Major threats to marine systems
Major threats to marine systems
Coastal development
Overfishing
Use of fishing trawlers
Runoff of nonpoint source pollution
Point source pollution: Discharge pollutants at specific locations
Habitat destruction
Introduction of invasive species
Climate change from human activities
Pollution of coastal wetlands and estuaries
Why Are Freshwater Ecosystems Important?
Water Stands in Some Freshwater Systems and Flows in Others
Standing (lentic) bodies of freshwater: Lakes, ponds, inland wetlant=ds
Flowing (lotic) systems of freshwater: Streams and rivers
Littoral zone: Near shore where rooted plants grow, high biodiversity,
Turtles, frogs, crayfish, and some fish
Limnetic zone: Sunlight area away from shore, main photosynthetic zone, some larger fish
Profundal zone: Deepwater too dark for photosynthesis, low oxygen levels, with some fish
Benthic zone: Decomposers, detritus feeders, and some fish, nourished primarily by dead matter
Major Services Provided by Freshwater Systems
Ecological Services:
Climate moderation
Nutrient cycling
Waste treatment
Flood control
Groundwater recharge
Habitats for many species
Genetic resources and biodiversity
Scientific information
Economic Services:
Food
Drinking water
Irrigation water
Hydroelectricity
Transportation corridors
Recreation
Employment
Some Lakes Have More Nutrients Than Others
Oligotrophic Lakes: Low levels of nutrients and low NPP with very clear water
Eutrophic Lakes: High levels of nutrients and high NPP and murky water with high turbidity
Mesotrophic Lakes: Commonly clear water lakes and ponds with beds of submerged aquatic plants and medium levels of nutrients
Cultural Eutrophication: This occurs when sewage, detergents, fertilizers, and other nutrient sources are introduced into the ecosystem as a result of human water pollution, accelerating the aging process.