Excess Nutrients
(Nitrogen and Phosphorus) |
cause blooms of algae that block sunlight from underwater plants; as algae decomposes it depletes oxygen in the water |
runoff from farms and lawns; sewage treatment plants and other point sources; atmospheric pollution
| Sediments |
cloud the water, decrease the amount of light reaching underwater plants; smother bottom dwelling organisms; alter bottom dwelling communities; prevent young oysters from settling |
runoff from construction sites, mining and logging sites, agricultural land; increased erosion in streams due to increased runoff velocity from paved lands |
| Toxic Substances |
poison animals and plants outright; cause disease; build up in tissue, making them toxic to eat; accumulate in bottom sediments affecting animals and plants in the future |
discharges from induskial facilities; sewage treatment plants; runoff from streets and parking lots
| Biodegradable Waste |
depletes oxygen in the water as it decomposes |
sewage treatment plants, runoff |
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