Chapter 8 Aquatic Biodiversity
Dec 28, 2015
Chapter 8Chapter 8
Aquatic Biodiversity
Natural Capital: Major Life Zones and Vertical Zones in an OceanNatural Capital: Major Life Zones and Vertical Zones in an Ocean
Fig. 6-1a, p. 126
Core Case Study:Why Should We Care About Coral Reefs?
Core Case Study:Why Should We Care About Coral Reefs?
• Coral reefs form in clear, warm coastal waters of the tropics and subtropics.– Formed by massive
colonies of polyps.
Figure 8-1Figure 8-1
Core Case Study:Why Should We Care About Coral Reefs?
Core Case Study:Why Should We Care About Coral Reefs?• Help moderate atmospheric temperature by
removing CO2 from the atmosphere.
• Act as natural barriers that help protect 14% of the world’s coastlines from erosion by battering waves and storms.
• Provide habitats for a variety of marine organisms.
Fig. 6-7b, p. 131
Estuaries and Coastal Wetlands: Centers of Productivity
Estuaries and Coastal Wetlands: Centers of Productivity
• Estuaries provide ecological and economic services.– Filter toxic pollutants, excess plant nutrients,
sediments, and other pollutants.– Reduce storm damage by absorbing waves and
storing excess water produced by storms and tsunamis.
– Provide food, habitats and nursery sites for many aquatic species.
Fig. 8-7
All consumersand producers to decomposersSecondary to
higher-level consumer
Primary to secondary consumer
Producer to primary consumer
Soft-shelledclam
BacteriaClamworm
Zooplankton andsmall crustaceans
Smelt
MarshPeriwinkle
Phytoplankton
Herring gulls
SnowyEgret
Peregrine falcon
Cordgrass
Short-billedDowitcher
Case Study:Dams, Wetlands, Hurricanes, and New Orleans
Case Study:Dams, Wetlands, Hurricanes, and New Orleans
• Dams and levees have been built to control water flows in New Orleans.
• Reduction in natural flow has destroyed natural wetlands.– Causes city to lie below sea-level (up to 3 meters).– Global sea levels have risen almost 0.3 meters since
1900.
Mangrove ForestsMangrove Forests
Figure 6-8Figure 6-8
What Kinds of Organisms Live in Aquatic Life Zones?What Kinds of Organisms Live in Aquatic Life Zones?• Aquatic systems contain floating, drifting,
swimming, bottom-dwelling, and decomposer organisms.– Plankton: important group of weakly swimming, free-
floating biota.• Phytoplankton (plant), Zooplankton (animal), Ultraplankton
(photosynthetic bacteria)
– Necton: fish, turtles, whales.– Benthos: bottom dwellers (barnacles, oysters).– Decomposers: breakdown organic compounds (mostly
bacteria).
Rocky and Sandy Shores: Living with the TidesRocky and Sandy Shores: Living with the Tides
• Organisms in intertidal zone develop specialized niches to deal with daily changes in:– Wave action
Figure 8-9Figure 8-9
Human Activities Are Disrupting and Degrading Marine SystemsHuman Activities Are Disrupting and Degrading Marine Systems
• Major threats to marine systems – Coastal development– Overfishing– Runoff of nonpoint source pollution– Point source pollution– Habitat destruction– Introduction of invasive species– Climate change from human activities– Pollution of coastal wetlands and estuaries
Freshwater Life ZonesFreshwater Life Zones
Sunlight
Paintedturtle
Greenfrog
Pondsnail
Blue-wingedteal
Muskrat
Plankton
Northernpike
BloodwormsYellowperch
Divingbeetle
Littoral zone
Limnetic zone
Profundal zone
Benthic zone
Fig. 8-15
Types of Lakes: OligotrophicTypes of Lakes: Oligotrophic
Types of Lakes: EutrophicTypes of Lakes: Eutrophic
Effects of Plant Nutrients on Lakes:Too Much of a Good Thing
Effects of Plant Nutrients on Lakes:Too Much of a Good Thing
• Plant nutrients from a lake’s environment affect the types and numbers of organisms it can support.
Figure 8-16Figure 8-16
River SystemsRiver SystemsRunoffRunoffWatershedWatershed
Drainage basinDrainage basinFloodplainFloodplain
Rain and snow
Source Zone
Water
Sediment
Lake Glacier RapidsWaterfall
TributaryFlood plain
Oxbow lake
Salt marsh
Delta Ocean
Depositedsediment
Transition Zone
Flood-Plain ZoneFig. 8-17
Source area
Rachel CarsonRachel Carson
• All at last returns to the sea-to Oceanus, the ocean river, like the ever-flowing stream of time, the beginning and the end.
• End chapter 8