Chapter 8 Flashcards
Is water renewable?
Yes, but distribution is unequal and lacks safe water.
Evaporation & Transpiration (ET)
Water to gas
Evaporation of water from plants
Water table
The top point of zone of saturation. The upper limit.
Zone of saturation
Lots of water. Fills the air spaces underground. Completely filled up.
Infiltration
When water goes into the ground. Atmosphere to surface.
Precolstion
Water moving in different directions going more into the ground.
Precipitation
Any form of moisture to the Earth
Measured with rain gauges–devices that capture precipitation and allow it to be measured by depth, weight or volume
Las Vegas Annual Precipitation
4-4.5 inches
Evaporation
Loss of moisture from vegetation (stomata)
Actual evapotranspiration (AE)
How much water actually is evapotranspired and is limited by the amount of water that is available.
Potential evapotranspiration (PE)
(water demand)
Amount of water that would evaporate and transpire under optimum moisture conditions
Evaporation/Transportation (ET) measured
Evaporation pan measures evaporation
Lysimeter measures both evaporation and transpiration
Measuring Potential evapotranspiration (PE)
Amount of water that would evaporate and transpire under optimum moisture conditions
Ex: water to plants
(Based on mean air temperature and day length)
Deficit
Demand exceeds the moisture from precipitation (P)
Ex: droughts
Surplus
Additional water beyond potential evapotranspiration demands
Delta S
+recharge
-soil moisture
Un-saturated soil
Still has water. Not completely dry.
Baseflow
The bottom of the water bed, flows in the river.
Drainage Basin
Where all the little streams flow into. The main stream.
Groundwater
Water below the surface
Beyond the soil-moisture zone
Out of the reach of plants.
Porosity
Spaces or voids between particles in a material such as
soil or rock.
Permeability
Ability of water to flow through soil or rock.
Aquifer
Subsurface body of permeable
rock or sediments through which water can flow.
Perched water table
An unconfined aquifer has a permeable layer above, and an impermeable layer beneath.
Unconfined aquifer
Has a permeable layer above an impermeable layer beneath.
Cone of depression
Water table lowered into a point.
Saturated zone
Water fills spaces between perticles.
Artesian wells
Ground water sloping where ground water is under pressure.
Drawdown
Lowering of water table; reversal of flow
