Chapter 8. Aquatic Biodiversity. Natural 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?. Coral reefs form in clear, warm coastal waters of the tropics and subtropics. Formed by massive colonies of polyps.
Fig. 6-1a, p. 126
Coral reefs form in clear, warm coastal waters of the tropics and subtropics.
Formed by massive colonies of polyps.
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 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.
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.
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).
Organisms in intertidal zone develop specialized niches to deal with daily changes in:
Major threats to marine systems
Runoff of nonpoint source pollution
Point source pollution
Introduction of invasive species
Climate change from human activities
Pollution of coastal wetlands and estuaries
Plant nutrients from a lake’s environment affect the types and numbers of organisms it can support.
Rain and snow
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