Water Resources Flashcards
6 cards from real Environmental Science practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Water Resources flashcards as text
What percentage of Earth's water is freshwater available for human use (in rivers, lakes, and accessible groundwater)?
Answer: About 1%
Only about 1% of Earth's water is accessible freshwater; the rest is saltwater, ice caps, or deep groundwater.
Which U.S. law establishes the basic structure for regulating pollutant discharges into navigable waters?
Answer: Clean Water Act
The Clean Water Act (1972) set the framework for regulating discharge of pollutants and established water quality standards.
What is an aquifer?
Answer: A layer of permeable rock or sediment that stores and transmits groundwater
An aquifer is an underground geological formation of permeable rock or sediment that holds and transmits significant quantities of groundwater.
What is the primary cause of saltwater intrusion into coastal freshwater aquifers?
Answer: Over-pumping of groundwater
Excessive groundwater pumping lowers water table pressure, allowing denser saltwater from the ocean to move inland.
Which watershed management concern arises when agricultural irrigation water evaporates, leaving minerals behind in soil?
Answer: Salinization
Salinization occurs when irrigation water evaporates and salts accumulate in topsoil, reducing agricultural productivity.
What does BOD (Biochemical Oxygen Demand) measure in water quality assessment?
Answer: The amount of oxygen consumed by microbes decomposing organic matter
BOD measures how much oxygen microorganisms use to decompose organic waste, indicating the level of organic pollution.