Question

water quality question:
compared to the original condition of the river, how has monitoring and regulating nitrate fertilizer runoff plus eliminating ddt runoff affected water quality in the peril river watershed?
a. it has increased dissolved oxygen levels in the water, which is beneficial to many organisms, including fish.
b. it has decreased the amount of algae and bacteria in the water.
c. it has altered the color of the water. the water is no longer green in color.
d. all of the above.

Explanation:

• For option A: Nitrate fertilizer runoff can cause eutrophication (algal blooms) which deplete dissolved oxygen. Reducing nitrate runoff and eliminating DDT (a pollutant) would improve water quality, increasing dissolved oxygen, beneficial for organisms like fish.
• For option B: Nitrate runoff fuels algal and bacterial growth. Reducing it and removing DDT (which can harm organisms and disrupt ecosystems, potentially affecting microbial populations) would decrease algae and bacteria.
• For option C: Algal blooms (from nitrate runoff) can make water green. Reducing algae (from less nitrate) would change the water color, removing the green tint.

Since A, B, and C are all valid effects of the described actions, the correct option is D.

Answer:

D. All of the above.