Groundwater

Definition

Groundwater is water that is found beneath the earth's surface in soil pore spaces and fractures of rock formations. It plays a critical role in the water cycle, acting as a reservoir that feeds into rivers, lakes, and oceans, while also being a vital source of drinking water for many communities. Understanding groundwater helps in comprehending how water moves through the environment and interacts with geological materials.

5 Must Know Facts For Your Next Test

1. Groundwater makes up about 30% of the world's fresh water supply, making it essential for agriculture, industry, and personal consumption.
2. Recharge areas are regions where surface water infiltrates into the ground to replenish aquifers, which is crucial for maintaining groundwater levels.
3. Groundwater can become contaminated from pollutants on the surface, making its protection important for both ecological health and human safety.
4. The movement of groundwater is influenced by gravity and pressure gradients, leading to varying rates of flow depending on geological conditions.
5. Wells are commonly used to extract groundwater, but over-extraction can lead to problems like land subsidence and decreased water quality.

Review Questions

• How does groundwater contribute to the overall water cycle?
  • Groundwater plays an essential role in the water cycle by acting as a reservoir that stores water underground. It contributes to surface water bodies such as rivers and lakes through processes like base flow, where groundwater discharges into these systems. Additionally, groundwater can recharge from precipitation during rain events, linking it back to surface water and facilitating its continual movement within the cycle.
• Discuss the importance of aquifers in relation to groundwater resources and management.
  • Aquifers are crucial for managing groundwater resources as they determine where and how much groundwater can be stored and accessed. They provide vital supplies for drinking water and irrigation in many regions. Effective management of aquifers involves monitoring recharge rates, preventing contamination, and ensuring sustainable extraction to maintain their health and availability for future generations.
• Evaluate the potential environmental impacts of groundwater over-extraction on local ecosystems and human communities.
  • Over-extraction of groundwater can lead to significant environmental impacts such as land subsidence, which can damage infrastructure and reduce land usability. It also lowers water tables, potentially drying up rivers and wetlands that depend on consistent groundwater levels. This disruption can affect local ecosystems by altering habitats for plants and animals, while also threatening human communities that rely on groundwater for drinking and agricultural needs. Long-term over-extraction can lead to irreparable damage to both ecosystems and water resources.

Related terms

Aquifer: An aquifer is a geological formation that can store and transmit groundwater, allowing it to be extracted for various uses like irrigation and drinking water.

Permeability:

Permeability is the ability of a material, such as soil or rock, to allow fluids to pass through it, which affects how easily groundwater can flow.

Water table: The water table is the upper surface of the saturated zone of groundwater, where the pressure in the groundwater equals atmospheric pressure.