Block 1 - Water Flashcards
Hydrosphere
The parts of earth that are mainly water (e.g. oceans, ice caps and lakes)
Hydrology
The study of water movement
Residence time
The average period that water stays in one part of the system before moving to another
Precipitation
Water that transfers from the atmosphere to the Earths surface
Interception
Precipitation which is stopped by vegetation before it reaches the ground
Evaporation
The process by which water is transferred as vapour from the land or ocean to the atmosphere
Humidity
A measure of how close the air is to saturation with water vapour
Latent heat of vaporisation of water
The energy required to completely convert one kilogram of water to steam without an increase in temperature.
Transpiration
the process by which plants draw up water from the soil through the xylem and transfer it to their leaves, from which it evaporates through stomata in the leaf system
Evapotranspiration
The process by which water moves from the land surface into the atmosphere as vapour. It combines both direct evaporation from wet surfaces and transpiration from vegetation.
Potential evapotranspiration
The maximum value of evaporation for a saturated surface, such as open water, in a given location.
Hydrologically effective precipitation
Effective precipitation. The difference between precipitation and actual evapotranspiration.
Aerodynamic resistance
A measure of the effectiveness of air movement in aiding evaporation, as a function of the ‘roughness’ of the surface over which it blows.
Stomatal resistance
The resistance to water loss through stomata in the leaves of a plant. Stomatal resistance depends on the number, type and size of the stomata and tends to be about ten times larger than aerodynamic resistance.
Canopy resistance
The resistance to evaporation of the overall vegetation canopy.
Lake
a body of water which contains a certain volume of water at a given time
Inflow
inflow = outflow + change in storage
Water balance
Precipitation - (streamflow + evapotranspiration) = Change in ground water + change in soil water storage
Ecosystem services
Direct of indirect contribution that ecosystems provide for human wellbeing and quality of life
Cultural ecosystem services
benefits that people obtain from an ecosystem through recreation, tourism, intellectual development, spiritual enrichment, creative and aesthetic experiences
Provisioning ecosystem services
benefit from the ecosystem such as food, drinking water, fire wood, natural gas, plants and medicine.
Regulating ecosystem services
benefit from the ecosystem which moderate natural processes such as pollination, decomposition, water purification, erosion , flood control, carbon storage and climate regulation
Supporting ecosystem services
services that are necessary for the production of all other ecosystem services, e.g. biomass production, production of oxygen, soil formation, nutrient cycling, water cycling, provisioning of habitat.
pores
small spaces in a rock or soil
infiltration
The process whereby water from rainfall, irrigation, snowmelt
permeability
the measure of the ease with which a fluid can flow through rocks of soils
unsaturated zone
the zone between the land surface and the water table in which the pore spaces in rock or soil filled with both water and air
saturated zone
the zone below the water table in which all the pore spaces in rock or soil are filled with water
Water table
the level below which all pore spaces in rock or soil are full of water
groundwater
the water that penetrates the ground surface and is contained in pore spaces in rocks located below the water table
capillary retention
water clings to the walls of narrow openings
porosity
porosity (%) = (pore volume / total volume) X 100%
secondary porosity
The porosity that has been caused by fractures or weathering in a sock after it has been formed
pore space volume
Pore space volume = (mass rock wet - mass rock dry) / density of fluid
