What Is a Critical Load

question 15

Multiple Choice

What is 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% of the species present
• C) the maximum abundance level of a particular species, beyond which additional numbers will degrade a habitat
• D) the amount of added nutrient that can be absorbed by plants without damaging ecosystem integrity
• E) the number of predators an ecosystem can support that effectively culls prey populations to healthy levels

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Definitions:

Equilibrium Reaction

A chemical reaction in which the forward and reverse reactions occur at the same rate, so that the concentrations of the reactants and products do not change with time.

Equilibrium Constant

A numerical value that expresses the ratio of the concentrations of products and reactants of a chemical reaction at equilibrium.

HA

Often shorthand for hydroxyapatite, a mineral form of calcium apatite; can also refer to hyaluronic acid or other context-specific chemical compounds.

Equilibrium

A state in which opposing forces or influences are balanced, often used in chemistry to describe reactions where reactants and products are formed at the same rate.