Question

It’s springtime, and you begin caring for your lawn. You patch areas that need more grass growing and spread fertilizer on the lawn to ensure lush, green grass for the summer. About June, you notice that the pond at the end of your yard has a green “scum” floating on the surface, and by July you see dead fish floating on the pond. What happened?

Choices

Fertilizer dissolved in the water has shut out sunlight for photosynthetic organisms at the base of the food pyramid.

Fish have overfed on algae.

The pond has undergone secondary succession.

Algae have produced toxins that kill fish.

The pond has undergone eutrophication.

Answer 1

Answer:

About June, you notice that the pond at the end of your yard has a green "scum" floating on the surface, and by July you see dead fish floating on the pond. What happened?

• Fertilizer dissolved in the water has shut out sunlight for photosynthetic organisms at the base of the food pyramid.
• Fish have overfed on algae
• The pond has undergone a secondary succession
• Algae have produced toxins that kill fish
• The pond has undergone eutrophication - Correct Option (eutrophication refers to a great increase in the phytoplankton or micro-algae population in water as a result of increase in the nutrient levels (due to addition of fertilizers to lawn in this case). Due to this, the oxygen content in the pond depletes causing hypoxia and fish death.)