chapter 15

Question 1

Problems associated with the Colorado River (Past &Present)

Answer 1

-people in Las Vegas are drilling for underground water, even though it threatens the area’s ecology

Question 2

Tributary

Answer 2

a smaller river slowing into a larger one

Question 3

Oxbow

Answer 3

an extreme bend in a river

Question 4

Oxbow lake

Answer 4

the bend is cut off and remains as an isolated, U-shaped body of water

Question 5

Floodplain

Answer 5

areas nearest to the river’s course that are flooded periodically
Frequent deposition of silt makes floodplain soils

Question 6

Riparian

Answer 6

riverside areas that are productive and species-rich

Question 7

Freshwater systems (amount, where it is located, etc.)

Answer 7

• relatively pure, with dissolved salts
• only 2.5% of earth’s water is fresh
• most freshwater is tied up in glaciers and ice caps

Question 8

Wetlands

Answer 8

Systems that combine elements of freshwater and dry land

Question 9

Freshwater marshes

Answer 9

shallow water allows plants to grow about the water’s surface

Question 10

swamps

Answer 10

shallow water that occurs in forested areas

can be created by beavers

Question 11

Bogs

Answer 11

ponds covered in thick floating mats of vegetation

a stage in aquatic succession

Question 12

Why wetlands are valuable

Answer 12

slow runoff

• reduce flooding, recharge aquifers filter pollutants
• people have drained wetlands, mostly for agriculture
• southern canada and the US have lost more than half of their wetlands

Question 13

Littoral zone

Answer 13

region ringing the edge of a water body

Question 14

Benthic zone

Answer 14

extends along the bottom of the water body

home to many invertebrates

Question 15

Limnetic zone

Answer 15

open portions of lake or pond where the sunlight penetrates the shallow waters

Question 16

Profundal zone

Answer 16

water that sunlight does not reach

supports fewer animals because there is less oxygen

Question 17

Oligotrophic lakes and ponds

Answer 17

have low nutrient and high oxygen conditions

Question 18

Eutrophic lakes and ponds

Answer 18

have high nutrient and low oxygen conditions

Question 19

Inland seas

Answer 19

large lakes that hold so much water, their biota is adapted to open water

Question 20

Groundwater

Answer 20

any precipation that does not evaporate flow into waterways, or get taken up by organism
makes up one fifth of the earth’s freshwater supply

Question 21

Aquifers

Answer 21

porous sponge-like formations of rock, sand, or gravel that hold groundwater

Question 22

Zone of aeration

Answer 22

pore spaces are partially filled with water

Question 23

Zone of saturation

Answer 23

spaces are completely filled with water

Question 24

Water table

Answer 24

boundary between two zones

Question 25

Aquifer recharge zone

Answer 25

any area where water infiltrates Earth’s surface and reaches aquifers

Question 26

Confined/artesian aquifers

Answer 26

water-bearing, porous rocks are trapped between layers of less permeable substrate -is under a lot of pressure

Question 27

Unconfined aquifer

Answer 27

- no upper layer to confine it - readily recharged by surface water - Groundwater becomes surface water through springs or human-drilled wells - Ground water may be ancient: the average age is 1,400 years

Question 28

Consumptive use

Answer 28

water is removed from an aquifer or surface water body, and is not returned

Question 29

Non-consumptive use

Answer 29

does not remove or only temporarily removes, water from an aquifer or surface water

Question 30

Dam

Answer 30

- any obstruction place in a river or stream to block the flow of water so water can be stored in a reservoir - to precent floods, provide drinking water, allow irrigation, and generate electricity

Question 31

Benefits & drawbacks of dams (Three Gorges Dam Example)

Answer 31

Benefits for three Gorges Dam Provides flood control, passage for boats, and electricity Removal is flooding cities and homes drowning famland and habitat pollutants will be trapped ``` Removal (why & controversies surrounding them) Benefits Power generation Flood control shipping drinking water ``` Drawbacks Habitat alteration population displacement Sediment capture

Question 32

water mining

Answer 32

withdrawing water faster than it can be replenished

Question 33

Dikes & levees

Answer 33

Long raised mounds of earth along the banks of rivers holding rising water in channels levees can make floods worse by forcing water to stay in channels and overflow

Question 34

Aral Sea - Past & Present

Answer 34

location => to the right of the caspian, between Kazakhstan and Uzbekistan

Question 35

irrigation efficiency

Answer 35

only 45% of water is absorbed by crops via “flood and furrow” irrigation -overirrigation leands to waterlogging, salinization, and lost farming income

Question 36

Sinkholes

Answer 36

areas were ground gives way unexpectedly | some cities are slowly sinking

Question 37

Desalinization

Answer 37

removal of salt from seawater or other water of marginal quality

Question 38

Distilling vs. reverse osmosis

Answer 38

distilling hastens evaporation and condenses the vapor reverse osmosis forces water through membranes to filter out salts

Question 39

Pathogens/waterborne disease

Answer 39

enters water supply via inadequately treated human waste and animal waste via feedlots causes more human health problems than any other type of water pollution

Question 40

Toxic chemicals

Answer 40

from natural and synthetic sources pesticides, petroleum products, synthetic chemicals arsenic, lead, mercury, acid rain, acid drainage from mines effects include: poisoning animals and plants, altering aquatic ecosystems, and affecting human health

Question 41

Sediment pollution

Answer 41

sediments can impair aquatic ecosystems clear-cutting, mining, poor cultivation practices dramatically changes aquatic habitats, and fish may not survive Solutions: better management of farms and forests; avoid large-scale disturbance of vegetation

Question 42

Thermal pollution

Answer 42

water water holds less oxygen dissolved oxygen decreases as temperature increases water that is too cold can kill aquatic organisms

Question 43

point source water pollution

Answer 43

discrete locations of pollution | factory or sewer pipes

Question 44

Nonpoint sources water pollution

Answer 44

pollution from multiple cumulative inputs over a large area | farms, cities, streets, neighborhoods

Question 45

U.S Clean Water Act

Answer 45

addressed point sources | targeted industrial discharge

Question 46

Do Nonpoint or point sources have a greater impact on quality?

Answer 46

nonpoint sources have a greater impact on quality

Question 47

Biological indicators

Answer 47

presence of fecal coliform bacteria and other disease-causing organisms

Question 48

Chemical indicators

Answer 48

pH, nutrient concentration, taste, odor, hardness, dissolved oxygen

Question 49

Physical indicators:

Answer 49

turbidity, color, temperature

Question 50

Sources of Groundwater pollution

Answer 50

``` natural aluminum, fluoride, sulfates pollution from human causes wastes leach through soils pathogens enter through improperly designed wells Hazardous wastes pumped into ground ``` Agricultural pollution nitrates from fertilizers pesticides dected in more than half of shallow aquifers tested

Question 51

Wastewater

Answer 51

water that has been used by people in some way | sewage, showers, sinks, manufacturing, storm water runoff

Question 52

Septic systems

Answer 52

the most popular method of wastewater disposal in rural areas underground septic tanks separate solids and oils from wastewater water drains into a drain field decompose the water solid waste needs to be periodically pumped and landfilled

Question 53

Primary treatment

Answer 53

physical removal of contaminants in settling tanks (clarifers)

Question 54

Secondary treatment

Answer 54

water is stirred and aerated so aerobic bacteria degrade organic pollutants water treated with chlorine is piped into rivers or ocean

Question 55

Clean Water Act

Answer 55

illegal to discharge pollution without a permit standards for industrial wastewater funded sewage treatment plants