Ch 9 Flashcards
Outgassing:
Water deep in the interior of the earth (below crust), are released in the form of gas (vapors)
Eustasy:
global sea level caused by changes in the volume of water in the oceans
In a globe, where is mostly water and where is mostly land
Land is mostly found in the northern hemisphere, water in the southern hemisphere
The hydrological cycle
Vast currents of water, water vapor, ice, and associated energy
3 components:
1- atmosphere
2- surface
3- subsurface
What happens in
the atmosphere part?
Evaporation + transpiration = evapotranspiration
transpiration: when plants release water to the atmosphere through small openings called stomata in their leaves, which is another way water moves into the atmosphere from land environments including water moving from the soil into plant roots and passing through their leaves to the air
What happens in the surface?
Interception
stemflow
through fall
what happens in the subsurface?
infiltration
Overland flow
surface run off
percolation
Infiltration:
Water get soaked by the soil
What happens if the ground surface is permeable?
then it won’t soak up the water
surface run off:
Same as overland flow
Overland flow
Surplus of water on surface so it causes a runoff in an area
Percolation:
the movement of water through rocks and soil, filtering downwards after it has infiltrated the ground
Soil-moisture zone
area where most of the water is stored in the soil, and roots have access to it
Zone of saturation
When soil is fully saturated, extra water moves downward as gravitational water into deeper groundwater, filling all spaces in the soil
Base flow
when water table reaches a stream, groundwater flows into the stream
describe the water budget:
measures the input of precipitation and its outputs like evapotranspiration, evaporation, and transpiration from plants, and surface runoffs, and moisture in the soil moisture zone.
income = precipitation
expenditure = run off, evaporation, transpiration
savings account = soil moisture storage
Rain gauge:
measures the amount of precipitation, its like a big cup that collects all of it
Potential evapotranspiration:
the amount of water that would evaporate and transpire if there was always enough water available
Actual evapotranspiration:
the water deficit, the subtraction of the water deficit by the (PE)
3 categories of water:
gravitational: drains downwards after filling the soil pore spaces
hygroscopic and capillary:
Both remain in the soil but ONLY capillary is accessible to plants image below
Why is hygroscopic water not accessible to plants?
it is a thin molecule layer tightly bound to each soil particle by the hydrogen bonding of water molecules
Wilting point of a plant:
when soil moisture only contains inaccessible water, so plants wilt and die
Capillary water:
valid for plants
Gravitational water:
un valid for plants as it percolates deep to the groundwater zone
Soil moisture utilization:
(desperation)
When plants use any moisture they can get from the soil to survive
Meteorological drought:
defined by the degree of dryness. This definition is region-specific, since it relates to atmospheric conditions that differ from area to area.
Agricultural drought:
occurs from shortages of precipitation and soil moisture affect crop yields.
Hydrological drought:
The effects of precipitation shortages (both rain and snow) on water supply, such as when streamflow decreases, reservoir levels drop, mountain snowpack declines, and groundwater mining increases.
socioeconomic drought:
when reduced water supply causes the demand for goods or services to exceed the supply, such as when hydroelectric power production declines with reservoir depletion.
Effects of climate change:
Lake levels are rising due to glaciers being melted at a rapid late, also causing freshwater to mix with saline water lower overall salinity in the ocean.
Hydropower:
electricity generated using the power of moving water
Wetland:
an area that is permanently or seasonally saturated with water and characterized by vegetation adapted to glycolic soils
Water found in wet lands is all freshwater
Where is groundwater found?
Beneath the surface that is beyond soil root zone
Zone of aeration:
a zone above the water table that has air in its pore spaces which may or may not have water
Zone of saturation:
(opposite of aeration)
a zone above the water table that has water filled in all its pores
Water table
the upper surface of groundwater, it’s the contact point between the zone of aeration and the zone of saturation
Aquifer:
subsurface layer of permeable rock or unconsolidated materials (silt, sand, or gravels) through which groundwater can flow in amounts adequate for wells and springs
Unconfined:
permeable layer above allowing water to pass through and an impermeable layer below
Confined:
Bounded above and below with permeable layers of rock or unconsolidated materials
