Chapter 11 - Soil and Water Resources Flashcards
soil
the layer of sediment closest to Earth’s surface into which plant roots extend and that has been modified by organisms and water
pedogenesis
the process of soil formation, which occurs through the weathering of rocks, the activities of organisms, the movement of rainwater, and time
weathering
the process by which solid rock is dissolved and broken apart into smaller fragments
bedrock
rock that is structurally part of and connected to Earth’s crust
regolith
loose Earth material the covers bedrock, including soil
soil horizons
horizontal zones within the soil that are identified by their different physical and chemical properties
leeching
process in which rainwater dissolves and carries nutrients downward
eluviation
the process in which rainwater carries soil particles downward
illuviation
the process in which rainwater deposits soil particles downward
loam
soil texture comprised of 40% sand, 40% silt, and 20% clay that contains a large amount of organic material, making it valuable to farmers as it retains and transmits moisture and nutrients that are easily accessible to plants, making it the ideal soil texture for growing most crops
humus
the brownish-black mixture of organic material that makes up the bulk of the O and A horizons by volume
groundwater
water found beneath Earth’s surface in sediments and rocks
soil taxonomy
widely-used soil classification system that arranges soils into 12 soil orders
desalination
removal of dissolved minerals and sediments in water
drought
prolonged period of water shortage
porosity
a measure of the available air space within soil, sediments, and rocks, expressed as a percentage
permeability
the ease with which water can flow through soil, sediments, and rocks
infiltration
process in which water on ground surface is pulled downward by gravity, like during a rainstorm or snowmelt, and enters the soil
percolation
process in which water moves around soil particles through narrow, meandering channels due to water’s cohesive and adhesive properties
aquifer
any sediment or rock with pores that contain water
aquiclude
any sediment or or rock layer that lacks pres and cannot contain water
zone of aeration
layer of the ground that is not permanently saturated
zone of saturation
layer of the ground that is usually heavily saturated with water
water table
top surface of the aquifer’s zone of saturation
groundwater recharge
the entry of water into an aquifer from the ground surface
groundwater discharge
the movement of water out of an aquifer and onto the ground surface
perched water tables
localized water tables that lie above the regional water table
spring
arises where hydraulic pressure pushes groundwater onto the surface
potentiometric surface
the elevation to which hydraulic pressure pushes water in pipes or wells
wells
holes dug or drilled by people to get water from the ground
artesian well
a well that has been drilled through an aquiclude into a confined aquifer below
groundwater overdraft
the removal of water from an aquifer faster than the aquifer is recharged at the site of the well
cone of depression
a cone-shaped lowering of the water table around the well from which water is being removed
saltwater intrusion
a process in which groundwater overdraft removes freshwater causing denser salt water to rise and contaminate the well
groundwater mining
the process of extracting groundwater from areas where there is little to no groundwater recharge
fossil groundwater
water that entered the aquifer long ago and is longer being replenished
contaminant plume
a cloud of pollution that migrates through the aquifer away from its source
groundwater remediation
the process of cleaning a contaminated aquifer
