Environmental Science & Ecology Flashcards

Agricultural runoff carrying excess nitrogen and phosphorus fertilizers most directly causes which environmental problem?

Answer: Eutrophication

Excess nutrients from fertilizer runoff trigger eutrophication, leading to algal blooms and subsequent oxygen depletion in water bodies.

Biomagnification refers to which of the following processes?

Answer: The increasing concentration of toxins at higher trophic levels

Biomagnification is the process by which persistent toxins like DDT become increasingly concentrated in organisms at successively higher trophic levels.

Which of the following is considered a primary air pollutant directly emitted from vehicle exhaust?

Answer: Carbon monoxide (CO)

Carbon monoxide is emitted directly from vehicle exhaust (primary pollutant), while ozone and PAN form through subsequent atmospheric reactions (secondary pollutants).

Acid rain is defined as precipitation with a pH value:

Answer: Below 5.6

Normal rain has a pH of about 5.6 due to dissolved CO2; acid rain is defined as precipitation with a pH below 5.6, caused by dissolved SO2 and NOx from combustion.

Which of the following best illustrates a point source of water pollution?

Answer: A municipal wastewater discharge pipe

Point source pollution originates from a single, identifiable location such as a discharge pipe; non-point sources like agricultural runoff are spread across large areas.

The primary indoor source of radon gas exposure in homes is:

Answer: Uranium-containing soil and rock beneath the building

Radon is a naturally occurring radioactive gas that seeps into buildings through foundations from uranium-bearing soil and bedrock below.

Which U.S. federal law establishes national ambient air quality standards (NAAQS) for outdoor air pollutants?

Answer: The Clean Air Act

The Clean Air Act, significantly expanded in 1970 and 1990, authorizes the EPA to set NAAQS and regulate emissions from stationary and mobile pollution sources.