They withdraw the greatest amounts for agriculture.
Which of the following water withdrawal habits do developing nations exhibit?
large; there are more particles (i.e., there is greater surface area) for the water to adhere to
Clay has a __________ field capacity because ________.
Of the example stations, which of the following experiences the greatest moisture deficits?
the removal of ground water at a rate faster than that at which it can be replaced
The term "ground water mining" refers to
Precipitation that reaches Earth's surface penetrates the soil surface through the process of
water that evaporates from an irrigated field
Which of the following is an example of the consumptive use of water?
A) dumps B) pesticides and fertilizers C) septic tanks
Which of the following is a potential source of ground water pollution?
78 percent of all precipitation falls on the oceans.
Which of the following is true regarding the hydrologic cycle?
the highest values are in the Southwest
Which of the following is true regarding potential evapotranspiration (POTET) in the United States?
Water is added to the soil when actual evapotranspiration is equal to potential evapotranspiration and the soil is full of moisture.
Which of the following conditions are necessary for a surplus to exist?
A) in the atmosphere
B) at the surface of the Earth and in the oceans
C) at a depth of up to several kilometers below the surface
The hydrologic cycle includes water
Excess surface water percolates through the zone of _________ to reach the zone of _________ and the water table.
Approximately what percent of the U.S. population derives a portion of its fresh water from groundwater sources?
created deficit abatement (drought-ending) precipitation that produced benefits exceeding damages
The line of contact between the zone of aeration and the zone of saturation is known as the
The water in a confined aquifer is under pressure of its own weight, creating a pressure level called the
Which of the following soil particle sizes is usually associated with the slowest recharge rate?
a depression in the water table formed by rapid ground water withdrawal
The term "cone of depression" refers to
precipitation; evaporation and transpiration
In the water budget, _________ is the major receipt and _________ is the major expenditure.
Which of the following would decrease the rate at which evapotranspiration occurs?
If precipitation and soil moisture are inadequate to meet potential evapotranspiration demands, the moisture condition is described as
B) available pore spaces (i.e., the soil's porosity)
C) flow of water through soil (i.e., the soil's permeability)
The texture and structure of the soil dictate
Which of the following types of soil would have the most water available for plant use following a rain?
The soil is holding the maximum amount of water that it can hold against the pull of gravity.
Which of the following is true when the soil is at field capacity?
A) subsurface flow from the land to the ocean
B) atmospheric water carried back to the ocean from land
C) surface water flow from the land to the ocean
Atmospheric water that is carried from the ocean to the land is balanced by
potential evapotranspiration exceeds actual evapotranspiration
Which of the following is normally true of a hot desert?
The highest amounts occur in the Southwest and extreme South
Which of the following is true of precipitation in North America?
This region of the High Plains aquifer is suffering the least from groundwater mining
the amount of water that would evaporate or transpire if it were available
Potential evapotranspiration refers to
If the field capacity increases while wilting point decreases, the amount of available water
Of the average precipitation over the lower 48 states, what percentage evaporates and transpires on the average per day?
Withdrawals increased 160 percent between 1950 and 1990
Which of the following accurately describes annual groundwater withdrawal in the United States?
The difference between the wilting point and field capacity is approximately equal to
The total amount of groundwater has been reduced by the mining of water.
Which of the following is true regarding groundwater?
A) salt water intrusion
B) compression of the aquifer, resulting in a permanent loss of water storage capacity
C) land subsidence and cracked building foundations
Which of the following is a potential consequence of ground water mining?
the water pressure in the soil is more than the water pressure in the plant
As transpiration occurs, water enters plant roots because ___________.
Although more water can be held in a clay soil, less is actually available for plant use than in a silt soil. T/F
Water could be pumped faster from a geologic unit composed of sand than from one composed of clay. T/F
Potential evapotranspiration (POTET), when reduced by the deficit (DEFIC), yields the actual evapotranspiration value for a given time period. T/F
The water available to a plant is a function of soil texture and the effective rooting depth of the plant itself. T/F
All plant species have the same amount of water available to them under the same soil moisture conditions. T/F
Soil moisture deficits are frequently overcome by irrigation in the arid and semi-arid agricultural regions of the world. T/F
Abnormally high cancer rates have occurred in the New Orleans area because of the contamination of the Mississippi River. T/F
An aquifer pumped beyond its recharge rate is over utilized and becomes a product of groundwater mining. T/F
When actual evapotranspiration is less than potential evapotranspiration, a soil moisture surplus exists. T/F
Ground water pollution that our generation creates will not be a problem in the future (decades to centuries) because it is easy to clean an aquifer once it is polluted. T/F
The ten largest rivers in the world combined, in terms of discharge, exceed the total groundwater resource. T/F