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RENR 375
Ch 8 Review
Question | Answer |
---|---|
How much of the Earth is covered with water | 71% |
How much of your body is covered made of water | 60% |
____ plays a key role in 1. Sculpting the earth, 2. moderating the climate, 3. removing pollutants | Water |
Water is one our most ______ managed resources | Poorly |
What % of the earths water supply is drinkable. | .024% |
The ____ cycle is the process of freshwater continually being collected, purified and recycled | Hydrologic |
We interfere with the _________ _______ when we cut down forests and destroy wetlands | Hydrologic Cycle |
Canada has ___ percent of the worlds population and ___ percent of the worlds fresh water | 5%, 20% |
China has _____ percent of the worlds population and ____ percent of the worlds fresh water supply | 19%, 7% |
_______ is water that seeps into the ground and percolated downward through spaces in soil and gravel | Groundwater |
The ______ ___ _____ is the point where below that depth the spaces are completely filled with water | Zone of Saturation |
The top of the one of Saturation is known as the ______ | Water Table |
The water table _____ in dry weather when we remove more groundwater faster than nature can replace it | Falls |
A geological layer with underground caverns and porous layer of san, gravel and rock through which groundwater flows are known as | Aquifers |
Most aquifers replenish naturally through _______ that perculates downward through soil and rock. | Precipitation |
The process of aquifer replenishing through precipitation is known as __________ | Natural recharge |
Aquifer replenishing from lakes, rivers and streams is know as | Lateral recharge |
_______ Aquifers get little if any recharge | Nonrenewable |
The freshwater from precipitation, melted snow that flows across the earths land surface into lakes, wetlands, streams and rivers is know as _____ | surface Water |
Precipitation that does not go into the ground or return to the atmosphere is called | Surface Runoff |
The land from which surface water drains into a river, lake or wetland is known as | Watershed or Drainage basin |
A scientist who studies the nature, distribution and movement of water is known as | Hydrologists |
2/3 of all surface runoff is lost in ______ | Season Floods |
1/3 of water that is not lost in runoff is known as | Reliable Surface Runoff |
______ percentage of the worlds reliable runoff is used each year | 34% |
In the arid southwest US what percentage of reliable runoff is used each year | 70% |
By 2025 what % of reliable runoff will be use | 90% |
How much of the reliable runoff do we actually use each year for crops and livestock | 70% |
How much of the reliable runoff does Industry use | 20% |
How much of the reliable runoff do cities and residences use | 10% |
In the Eastern US most of the water is used for | Power plant cooling and manufacturing |
In the Easter US the most serious water problems are | Flooding and pollution |
In the Western part of the US up to 85% of the water is used for | Irrigation |
Areas that have scarce water sources for growing urban areas, irrigation, recreation and wildlife are known as | Water Hotspots |
From 1975 to 2005 the amount of water used in the US has _____ | stayed the same |
A prolonged period in which precipitation is at least 70% lower and evaporation is higher than normal is known as | Drought |
What percentage of the earths land surface is currently experiencing extreme drought | 30% |
One in every _____ people in the world lack regular access to clean water for drinking, cooking and washing | seven |
Most of the water in Africa comes from 3 river basins: the Nile, Jordan and ________ | Tigris-Euphrates |
How many countries does the Nile river flow through | 7 |
What 3 countries use most of the water from the Nile river? | Ethiopia, Sudan, and Egypt |
Where in line is Egypt in the Nile river water system | Last |
What river in Africa runs in the most water short region | Jordan |
What countries fight for the water of the Jordan | Jordan, Syria, Palestine, Israel |
Which country threatens to dam the Jordan river preventing water flow to Jordan and Israel | Syria |
Which country controls the flow of the Tigris Euphrates River | Turkey |
What type of water source provides drinking water to half the worlds population | Aquifers |
In the US groundwater is being withdrawn from aquifers ______ faster than it is replenished | 4 times |
What is the name of the worlds largest aquifer | Ogallala |
Ogallala is located under _________ | 8 midwestern states |
Overpumping aquifers has caused the sand and rock in aquifers to collapse causing the land above to ______- | subside (Land subsidence) |
Groundwater overdrafts near costal areas can pull _______ into freshwater aquifers. | Saltwater |
With global water shortages, scientists are evaluating __________ as future water sources | Deep aquifers |
The quality of deep aquifers is _____ quality than water in rivers and lakes | higer |
Deep aquifers ________ be replenished | Can Not |
______ is known about geological effects of deep aquifer tapping | Little |
Deep water aquifers could lead to _____ _____ between countries | Water Wars |
What are the 3 drawbacks of deep aquifers | Nonrenewable, Little known, Water Wars |
Dans and reservoirs are used to ___________ | control floods, generate electricity, supply water for irrigation |
Hydro-electirc dams produce ____ of the the wolds electricity | 20% |
All of the land covered by water due to dams is equivalent to the size of _____ | California |
the 4 drawbacks of dams are: | 80million displaced people, water covers useful land, freshwater fish extinct, and rivers don't run freely |
How many of the 177 longest rivers on the planet run freely | 21 |
To deliver nutrients to the sea, Deposit silt to maintain deltas, purify water, renourish wetlands and provide habitat are all services of ________ | Rivers |
One of the worlds largest water transfer projects is the combination of the California Water Project and the | Central Arizona Project |
_______ consumes 3/4 of the water withdrawn in California | Agriculture |
READ THE ARAL SEA DISASTER IN CH 8 | READ THE ARAL SEA DISASTER IN CH 8 |
Removing disolved salts from ocean water is known as | Desalination |
Slightly salty water is know as ______ water | Brackish |
The process of desalination by boiling water and leaving behind salt is known as | Distillation |
THe process of using high pressure to force salt water through a membrane to desalinate the water is known as | Reverse Osmosis |
High cost, killing of marine organisms and huge quantities of salty waste water are all drawbacks of _______ | Desalination |
2/3 of the water used in the world is __________ through evaporation, leaks and other losses | Wasted |
__________ is the largest user of water and 1/2 of all that water is wasted. | THe US |
It is feasible to reduce water waste to _______, meeting the world's water needs | 15% |
A major cause of water waste is __________ | Low cost |
By heavily _______ water, governments give out the false message that water is abundant and can be wasted | Subsidizing |
________ encourages water conservation but makes it difficult for low income farmers to buy enough water to meet their needs | High water prices |
The second major cause of water waste is lack of ____________ for improving the efficiency of water use. | Government subsidies |
What % of the water used for irrigation does not even reach the crops? | 60% |
The process of removing water from well or water source, allowing it to flow by gravity through unlined ditches is called | Flood Irrigation |
Irrigation which causes pumps to spray water on a crop allowing 80% of the water to reach the crop is known as _______ irrigation | Center Pivot or low pressure sprinkler |
Drip irrigation, also known as _______, is the most efficient way to deliver small amounts of water precisely to crops | Microirrigation |
An important way to reduce flooding is to preserve ___________ and restore_________ | Existing wetlands, degraded wetlands |
Any change in water quality that can harm living organisms or make the water unfit for human use is known as____ | Water pollution |
The first major type of water pollution that discharges pollutants directly into bodies of surface water at specific locations are known as | Point sources |
The second major type of water pollution that is broad and diffuses pollutants off of large areas such as crop lands is called | Non-point sources |
___________ are the leading causes of water pollution | Agricultural Activities |
The second major source of water pollution is __________ which emit a variety of harmful inorganic and organic chemicals into the water supply | Industrial facilities. |
THe third biggest source of water pollution is _______ causing major erosion of soils and runoff of toxic chemicals | Mining |
Water pollutants speed up the spread of _________ among people who have to drink contaminated water | Infectious disease |
The World Health Organization predicts that 1.6 million people _____ from waterborne infectious disease | Die |
Diarrhea alone, caused mostly be exposure to polluted water, on average kills _________ every 18 seconds | a child |
In flowing streams, the breakdown of biodegradable waste by bacteria consumes oxygen creating | Oxygen Sag Curve |
Flowing rivers ________ recover rapidly from moderate levels of degradable waste as long as the river is no overloaded | Can |
According to the Wold Commission on Water, more than half of the 500 major rivers are | Heavily Polluted |
Polluted waterways occur in less developed countries because the government can not afford to build _________ | Waste Water Treatment Plants |
In ____________ most cities dump 80-90% of sewage into streams. | Less developed countries |
The first reason lakes and reservoirs are less effective at diluting pollutants is because lakes contain __________ that undergo very little vertical mixing. | Stratified Layers |
The second major reasons that Lakes and Reservoirs are not good at diluting pollutants is because they have little to no _______ | Flow |
Lakes and Reservoirs are __________ (more/Less) vulnerable than streams to contamination by runoff or plant discharge | MORE |
Lakes and reservoirs are subject to ____________ the natural nutrient enrichment of a shallow lake, estuary or slow moving steam by the runoff of nitrates from surrounding land | Eutrophication |
In urban or agricultural areas, human activities can greatly accelerate the input of plant nutrients called | Cultural Eutrophication |
During hot weather the nutrient overgrowth (eutrophication) can cause ________ or sudden dense growth of organisms like algae and cyanobacteria. | Blooms |
When these Blooms die off, the algae bacteria which degrades the algae deplete the water of much needed _________ | Oxygen |
The most expensive way to reduce cultural eutrophication |