Ecological Risk Assessment & Biodiversity Flashcards
6 cards from real CES practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Ecological Risk Assessment & Biodiversity flashcards as text
What is an ecological risk assessment?
Answer: A process that evaluates the likelihood of adverse ecological effects from exposure to environmental stressors
Ecological risk assessment evaluates the probability that adverse ecological effects (such as species decline or habitat loss) may occur as a result of exposure to environmental stressors including chemical contaminants.
What is a biological indicator (bioindicator) species?
Answer: An organism whose presence, abundance, or condition reflects environmental quality
Bioindicator species are sensitive to environmental changes and their health, population, or behavior provides information about the condition of their ecosystem, such as macroinvertebrates indicating stream water quality.
What is the Endangered Species Act (ESA) designed to protect?
Answer: Species at risk of extinction and the ecosystems on which they depend
The ESA (1973) provides for the conservation of species listed as endangered or threatened, including the protection of critical habitat necessary for their survival and recovery.
What is bioaccumulation in environmental science?
Answer: The gradual accumulation of a substance in an organism over time because the organism absorbs it faster than it can eliminate it
Bioaccumulation occurs when organisms absorb contaminants (like mercury or DDT) from water, food, or sediment faster than they can metabolize or excrete them, leading to increasing tissue concentrations over time.
What is the difference between an endangered species and a threatened species under the ESA?
Answer: An endangered species is in immediate danger of extinction; a threatened species is likely to become endangered in the foreseeable future
Under the ESA, 'endangered' means a species is in danger of extinction throughout all or a significant portion of its range, while 'threatened' means it is likely to become endangered within the foreseeable future.
What is biomagnification and how does it differ from bioaccumulation?
Answer: Biomagnification is the increasing concentration of a substance at each successive trophic level in a food chain, while bioaccumulation occurs within a single organism
Bioaccumulation occurs within an individual organism. Biomagnification describes how contaminant concentrations increase at each higher trophic level in a food chain, with top predators having the highest concentrations.