Watersheds may be contaminated by fertilizers and other pollutants. when these substances enter a waterway, they can cause algal blooms, which are rapid overgrowths of algae. when the algae die, the decay uses up a large portion of dissolved oxygen. declining oxygen levels can then cause large die-offs of animals in the waterway.

what will an algal bloom in a watershed most likely cause?

a)a decrease in the watershed’s biodiversity, which will reduce its ability to supply clean and safe drinking water.

b)a decrease in the watersheds ecosystem diversity, which would improve its ability to supply large volumes of water.

c)an increase in the watersheds genetic diversity, which would reduce its ability to supply clean and safe drinking water.

d)an increase in the watersheds species diversity, which would improve its ability to supply large volumes of water.