Page 309 - Geosystems An Introduction to Physical Geography 4th Canadian Edition

distillation or reverse osmosis. This processing yields potable water for domestic uses.
groundwater (p. 256)
zone of aeration (p. 260)
zone of saturation (p. 260) water table (p. 260)
aquifer (p. 260)
unconfined aquifer (p. 260) confined aquifer (p. 260) potentiometric surface (p. 260) artesian water (p. 260) drawdown (p. 260)
cone of depression (p. 260) groundwater mining (p. 261) desalination (p. 261)
19. Are groundwater resources independent of surface supplies, or are the two interrelated? Explain your answer.
20. Make a simple sketch of the subsurface environment, labeling zones of aeration and saturation and the water table in an unconfined aquifer. Then add
a confined aquifer to the sketch.
21. At what point does groundwater utilization become groundwater mining? Use the High Plains Aquifer example to explain your answer.
22. What is the nature of groundwater pollution? Can contaminated groundwater be cleaned up
Chapter 9 Water resources 273 easily? What is fracking and how does it impact
groundwater?
■ Evaluate the water budget, and identify critical aspects of present and future freshwater supplies.
The world’s water supply is distributed unevenly over Earth’s surface. Water surpluses are used in several ways. Water withdrawal, also known as nonconsumptive use or offstream use, temporarily removes water from the sup- ply, returning it later. Consumptive use permanently re- moves water from a stream. Instream use leaves water in the stream channel; examples are recreation and hydro- power production.
water withdrawal (p. 266) consumptive use (p. 266)
23. Whatisthedifferencebetweenwithdrawalandcon- sumptive use of water resources? Compare these with instream uses.
24. Briefly assess the status of world water resources. What challenges exist in meeting the future needs of an expanding population and growing economies?
25. If wars in the 21st century are predicted to be
about water availability in the needed quantity and quality, what action could we take to understand the issues and avoid the conflicts?
looking for additional review and test prep materials? Visit the Study area in MasteringGeographyTM to enhance your geographic literacy, spatial reasoning skills, and understanding of this chapter’s content by accessing a variety of resources, including interactive maps, geoscience animations, satellite loops, author notebooks, videos, rSS feeds,
web links, self-study quizzes, and an eText version of Geosystems.
visualanalysis 9 A weighing lysimeter
A weighing lysimeter for measuring evaporation and transpiration. The various pathways of water are tracked: Some water remains as soil moisture, some is incorporated into plant tissues, some drains from the bottom of the lysimeter, and the remain- der is credited to evapotranspiration. Modelling natural conditions, the lysimeter measures actual evapotranspiration.
1. Briefly explain how this device measures the components of the water balance.
2. Describe what happens if there is precipitation on the lysimeter; follow the flow paths.
3. Please go to this web site and briefly take a look at a project to build the world’s largest lysim- eter, in the landscape evolution Observatory
at Biosphere 2 in arizona. What do you find
that related to Chapter 9? See the “Feature Project, leO” section on the Biosphere 2 web site, b2science.org/.
SCALE IN CM
[adapted from illustration courtesy of lloyd Owens, agricultural research Service, USDa, Coshocton, Ohio.]
PLOUGH LAYER SILT LOAM
ROTTEN SHALE DECOMPOSING SHALE
SHALE BEDROCK
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60 60
30 0 30 60
30
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30 0