Nitrogen and phosphorus are essential for plants and algae to grow. On page 5, the graphs suggest that increasing the amount of nutrients leads to more algae growth. Algae populations are important to aquatic ecosystems because they are the foundation of the food web and play key roles in the nitrogen, phosphorus, and carbon cycles. But what happens if the amount of nutrients in the water continues to increase?
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NARRATOR: What is Eutrophication? It’s a problem that should matter to you, whether you live near the ocean or not. That’s because it begins wherever people live, and ends with damage to resources we all use, and enjoy. It all starts when nutrients get into lakes and oceans. Remember, what’s waste to humans can be food to plants and other creatures. Nutrients feed algae, like they do other plants. Algae grows and blocks sunlight. Plants die without sunlight. Eventually, the algae dies too. Bacteria digest the dead plants, using up remaining oxygen, and giving off carbon dioxide. If they can’t swim away, fish and other wildlife become unhealthy, or die without oxygen. But it doesn’t have to be this way. Protecting marine resources starts with sound agricultural and waste management practices.
The excess nutrients contaminating a body of water cause nutrient pollution. When the concentration of nutrients in any body of water keeps increasing, it leads to a process called eutrophication, as shown in video. While this process occurs naturally over time, human activity that increases the amount of nutrient pollution entering the ecosystem can significantly speed up the process.
Click Arrange It to show what you know about the order of events that lead to eutrophication.