Earth and Environmental Science Unit 4 Test

Three types of wells

- Dug
- Driven
- Drilled

Dug wells

Digging with a pick and shovel

Driven wells

Driving a small diameter pipe into the soft earth

Drilled wells

Rotary drill bits mounted on a truck, chew away at the Earth, percussion bits that smash the rock

Negative effects of groundwater depletion

- Lowering of water table
- Increased costs for the user
- Reduction of water in streams and lakes
- Land subsidence : a loss of support below ground
- Deterioration of water quality

Pros of Dams

- hydroelectric power
- controlling waterways
- great source of irrigation
- environmental protection

Cons of Dams

- risk of sediment buildup
- damaging to environment
- erosion of surrounding soil
- high cost and risk for disaster

Consumptive Water Use

Water use in which the water is lost to the ecosystem

Non-Consumptive Water Use

Water use that recycles and doesn't use up the water supply

Irrigation used by farmers

Wasteful and Non-Wasteful

Wasteful Irrigation Methods

- Overhead sprinklers
- Trench irrigation
- Flood irrigation

Non-Wasteful Irrigation Methods

- Drip Irrigation

Water scarcity affects...

Approximately 2 billion people

Water Scarcity/Stress

The total # of people living in a country determines the per capita availability of water resources in that country

Population growth is...

A major contributor to water scarcity

Agricultural Uses of Water

- irrigation:
~ overhead sprinklers
~ trench irrigation
~ flood irrigation
~ drip irrigation

Industrial Uses of Water

- power plants
- oil refineries
- manufacturing

Recreational Uses of Water

- swimming
- fishing
- boating
- golf courses

Land Subsidence

The gradual settling and lowering of the Earth's surface

Land Subsidence occurs when...

Large amounts of groundwater have been withdrawn from certain types of rocks, such as fine-grained sediments.

Causes of Land Subsidence

- Most often caused by human activities, mainly from removal of subsurface water
- Compaction of soils in some aquifer systems can accompany excessive groundwater pumping

Effects of Land Subsidence

- Permanent reduction in the total storage capacity of the aquifer system
- Permanent Subsidence and related ground failures

Saltwater Intrusion

The induced flow of seawater into freshwater aquifers primarily caused by groundwater development near the coast

Causes of Saltwater Intrusion

- Lateral encroachment from coastal waves
- Vertical upcoming near discharging wells

Effects of Saltwater Intrusion

- Decreases freshwater storage in aquifers
- Can result in abandonment of supply wells

Estuary

A partially enclosed, coastal water body where freshwater from rivers & streams mixes with salt water from the ocean

Eutrophication

An over-enrichment of chemical nutrients (fertilizers) in a body of water. It can lead to algal blooms because plants aren't the only things that grow more quickly with fertilizers.

Macropores

Root systems, animal burrows, abandoned wells, & other systems of holes and cracks that supply pathways for contaminants

Point Source Pollution

Pollution that comes from a single source or point

Non-Point Source Pollution

Pollution that doesn't come from a single source or point

North Carolina has...

17 river basins

NC River Basins form

Land that water flows across or under on its way to a river

NC River Basins function

- Each river basin is like a living organism with its own circulatory system

River Basin

Land that water flows across or under on its way to a river

Continental Divide

One half of water goes to Gulf of Mexico and the other half goes to the Atlantic