Final answer:
Aquifers are underground reservoirs of fresh water that are important for drinking and irrigation. They can be accessed through wells and need to be protected and managed to ensure a sustainable water supply.
Step-by-step explanation:
Aquifers are underground reservoirs of fresh water that exist in the pores between particles in sand, gravel, or in the fissures in rocks. They are important sources of drinking and irrigation water, and can be accessed through wells. Aquifers are replenished by water percolating down from the surface, but they can also be depleted faster than they are being replenished. Protecting and managing aquifers is crucial for ensuring a sustainable water supply.