Final answer:
The human use of groundwater has increased over time, leading to various environmental issues such as depletion of aquifers, soil subsidence, and saltwater intrusion.
Step-by-step explanation:
Human use of groundwater has increased over time. Groundwater, being a crucial subsurface reservoir of fresh water, flows from areas of higher to lower elevations and is tapped for agricultural, industrial, and domestic purposes. As the demand for water rises, related phenomena such as groundwater mining, soil subsidence, and saltwater intrusion become more pronounced. This is particularly concerning because groundwater is not always a renewable resource and is being depleted in many areas faster than it can recharge, causing issues like water stress and the potential for water crises.