Question

Which of these will most likely occur if chemicals from fertilizers runoff into lakes and streams?

a. Aquatic plants will stop growing.
b. Aquatic animals will thrive.
c. Water quality will improve.
d. Fish will die from a lack of oxygen.

Answer 1

Excess nutrients from fertilizer runoff cause excessive growth of algae, leading to dead zones and massive fish kills.

Step-by-step explanation:

Excess phosphorus and nitrogen that enter these ecosystems from fertilizer runoff and from sewage cause excessive growth of algae. The subsequent death and decay of these organisms depletes dissolved oxygen, which leads to the death of aquatic organisms, such as shellfish and finfish. This process is responsible for dead zones in lakes and at the mouths of many major rivers and for massive fish kills, which often occur during the summer months.