Which of the following best describes a critical load?
A) the amount of nutrient augmentation necessary to bring a depleted habitat back to its former level
B) the level of a given toxin in an ecosystem that is lethal to 50 percent of the species present
C) the amount of added nutrient that can be absorbed by plants without damaging ecosystem integrity
D) the number of predators an ecosystem can support that effectively reduces prey populations to healthy levels

Question

Quizplus · Accepted Answer

A critical load refers to the threshold level of pollutant deposition (like nutrients) that an ecosystem can tolerate without suffering damage to its structure or function. It is the maximum level of nutrient input (such as nitrogen or sulfur) that an ecosystem can absorb without experiencing harmful effects, making option C the correct description.

Which of the Following Best Describes a Critical Load