Question

a scientist measured how the population of fish in a lake changed when a new factory was built nearby. based on the data in the graph below, what relationship do you see between water oxygen levels and the fish population? what might be causing the change you noticed, and how could this affect the ecosystem?

Explanation:

As the factory operates (time increases), water oxygen levels likely drop (from graph trends), and fish population decreases (negative correlation). Factory pollution (e.g., waste, chemicals) reduces oxygen via algal blooms or direct toxicity. This disrupts the ecosystem: fewer fish affect predators/prey, and oxygen loss harms aquatic life.

Answer:

Relationship: As water oxygen levels decrease (over time, likely due to the factory), the fish population also decreases (negative correlation).
Cause: The new factory likely pollutes the lake (e.g., releasing chemicals, increasing nutrient runoff that causes algal blooms which deplete oxygen).
Ecosystem Impact: Fewer fish disrupt food chains (predators lose a food source, prey of fish may overpopulate), and low oxygen harms other aquatic organisms, reducing biodiversity.