Major Ideas
- Eutrophication, is the over enrichment of the sea by nutrients that promote plant growth.
- The formation of dead zones cause harm to the marine ecosystem.
- Low water flows lead to slow replenishment of oxygen in bottom waters.
- Estimated of 60 million tons of benthic life perished from hypoxia; oxygen-deprived it no longer supported nonbacterial life.
Summary
The coastal seas are mostly dead zones, a dead zone forms when there is a lot of nutrients in the water. This occurs when high concentrations of nitrogen and phosphorus further the growth of plankton.