Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

IB Environmental Science & Systems > Unit 4: Water, Food Production Systems & Society > Flashcards

Unit 4: Water, Food Production Systems & Society Flashcards

1
Q

What are 4 reasons why water is important?

A
  1. keeps us alive
  2. moderates climate
  3. sculpts land
  4. removes and dilutes wastes and pollutants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How does water sculpt land?

A

erosion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What percent of the earth’s water supply is available to us as liquid freshwater?

A

1%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What percent of all water is saltwater?

A

97%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What percent of all water is freshwater?

A

2.6%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What percent of freshwater is frozen? (for now)

A

68.7%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What percent of freshwater is groundwater?

A

30.1%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What percent of Earth’s total water volume is available on the surface in lakes, rivers, and swamps?

A

0.3%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

If 2.6% of all water is fresh, then why is only 1% of the earth’s water supply available to us?

A

2/3 of freshwater is frozen, so we cannot use it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What percent of the total Earth’s water volume is water vapor in the atmosphere?

A

0.001%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

If all of the water in the atmosphere rained down at once, to what depth would it cover the ground?

A

2.5 cm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

When is a resource renewable?

A

a resource is renewable if it is replenished on a human time scale

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How long does it take a molecule of water to enter and leave a river storage?

A

12-20 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How long does it take a molecule of water to enter and leave an atmospheric storage?

A

9 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How long does it take a molecule of water to enter and leave a groundwater storage?

A

up to 300 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How long does it take a molecule of water to enter and leave an ice cap storage?

A

16,000 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How long does it take a molecule of water to enter and leave an ocean storage?

A

37,000 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How can water easily go from being a renewable to a non-renewable resource?

A

poor management

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which water storages are renewable?

A

atmosphere and rivers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which water storages are non-renewable?

A

oceans and icecaps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What water storage is a middle ground (either renewable or non-renewable)?

A

groundwater aquifers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the water cycle powered by?

A

solar radiation (the Sun)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What can water flows either be?

A

transfers or transformations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are 5 types of transfers that occur in the water cycle?

A
  1. advection
  2. flooding
  3. surface run-off
  4. infiltration and percolation
  5. stream flow and current
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

advection

A

wind-blown movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

infiltration and percolation

A

when water runs into and through soil or rocks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are 3 types of transformations that occur in the water cycle?

A
  1. evapotranspiration
  2. condensation
  3. freezing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

evapotranspiration

A

liquid to water vapor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

condensation

A

water vapor to liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the seven storages in the water cycle?

A
  1. oceans
  2. soil
  3. groundwater (aquifers)
  4. lakes
  5. rivers and streams
  6. atmosphere
  7. glaciers and icecaps
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are 4 ways humans impact the water cycle?

A
  1. withdrawals
  2. discharges
  3. changing flows (the speed at which water can flow and where it flows)
  4. diverting rivers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are 3 uses for humans to withdraw water?

A
  1. domestic
  2. irrigation
  3. industry
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

How do humans interrupt the movement of water through discharges?

A

adding pollutants to water (chemicals from agriculture, fertilizers, sewage)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

How do humans change flows in the water cycle?

A

creating dams, reservoirs, and channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Why do humans divert rivers?

A

rivers are directed away from important areas or towards dams to improve storage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

canalizing

A

converting a river into a navigable canal, leading to more rapid flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

permeable surfaces

A

allow water to percolate into the soil to filter out pollutants and recharge the water table

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

impermeable surfaces

A

solid surfaces that do not allow water to penetrate it, forcing it to run off

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What has water from the Aral Sea mostly been used for?

A

irrigation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Since 1961, what has happened to the Aral Sea’s salinity levels?

A

The Aral Sea’s salinity levels have tripled.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

How much has the water dropped in the Aral Sea?

A

22 meters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Where does most water from the Middle East come from?

A

the Nile, Jordan, Euphrates, or Tigris rivers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What percent has lake Chad in Africa shrunk by?

A

95%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What are 3 things many parts of the world experiencing?

A
  1. rivers running dry
  2. falling water tables from over pumped aquifers
  3. lake and seas shrinking
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

How many people live without clean drinking water?

A

1.1 billion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

How many people lack adequate sanitation?

A

2.6 billion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

How many people die every year from diarrheal diseases?

A

1.8 million

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

How many children die everyday from waterborne diseases?

A

3,900

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

How many river basins are shared by 2 or more countries mostly without adequate legal or institutional arrangements?

A

over 260

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What quantity of water is needed to produce 1 kg of wheat?

A

1,000 liters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What quantity of water is needed to produce 1 kg of rice?

A

1,400 liters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What quantity of water is needed to produce 1 kg of beef?

A

13,000 liters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is the daily water usage per person in residential areas in North America and Japan?

A

350 liters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What is the daily water usage per person in residential areas in Europe?

A

200 liters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What is the daily water usage per person in residential areas in sub-Saharan Africa?

A

20 liters or less

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What is the leading human use of water?

A

agriculture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What are the 6 human uses of water?

A
  1. domestic
  2. agriculture
  3. industry
  4. electricity
  5. transportation
  6. boundaries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

How do humans use water for transportation?

A

ships on lakes and rivers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

How do humans use water for domestic purposes?

A

water used at home for drinking, washing, cleaning, etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

How do humans use water for agriculture?

A

irrigation, for animals to drink

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

How do humans use water for industry purposes?

A

manufacturing, mining, cooling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

How do humans use water for electricity purposes?

A

most turbines are powered by steam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

How do humans use water as boundaries?

A

rivers and lakes mark boundaries between nation states

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

How much higher is agriculture water use than domestic water use?

A

agriculture water use is 10 times higher than domestic water use

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

What percent of human water use is for irrigation and electricity?

A

70%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What percent of human water use is for industries?

A

20%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What percent of human water use is for cities or residences?

A

10%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

What term does the UN use to refer to our current situation?

A

“water crisis”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What percent of humans alive today deal with some level of water scarcity?

A

up to 40%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

It isn’t that there’s not enough water world wide…

A

it’s that the water isn’t evenly distributed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

water scarcity

A

the demand for water exceeds available resources

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

physical water scarcity

A

when the demand of the population exceeds the available water resources of a region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

economic water scarcity

A

when human, institutional, or financial capital limit our access to water even though water in nature is available for human needs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Do poor households in developing countries or families in industrialized nations spend higher portions of their income on water?

A

poor households in developing countries spend more money on water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

What would sustainable use allow for?

A

full natural replacement of the resources exploited and full recovery of the ecosystems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

What are two sources of freshwater?

A

surface water and aquifers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What are examples of surface water?

A

rivers, streams, reservoirs, and lakes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

aquifer

A

a layer of porous rock (holds water) adjacent to a layer of impermeable rock (does not let water through)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

What do aquifers hold?

A

groundwater that can be extracted directly from the surface or via wells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

watershed/drainage basin

A

land where surface runoff drains downhill into a body of water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

reliable runoff

A

amount of surface runoff that is consistently available for use from year to year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

What happens to reliable runoff?

A

it soaks into the ground and becomes groundwater

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

In what kind of places can aquifers be refilled?

A

aquifers can only be refilled in places where the porous rock is exposed at the surface and infiltration from precipitation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

What happens to “fossil aquifers” that are no longer exposed at the surface?

A

the “fossil aquifers” are never recharged

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

How is the flow in an aquifer?

A

VERY slow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

What can be done to aquifers?

A

aquifers can be opened or confined

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

What are the two types of aquifers?

A

renewable aquifers and non-renewable aquifers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

natural recharge

A

aquifers are replenished naturally by precipitation and percolation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

lateral recharge

A

aquifers are recharged from the side by nearby streams and lakes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

At what speed do renewable aquifers recharge?

A

slowly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

Where are non-renewable aquifers located?

A

deep underground

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

How long ago did non-renewable aquifers form?

A

formed tens of thousands of years ago

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

What is an example of a non-renewable aquifer?

A

Ogalla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

Where is the Ogalla aquifer located?

A

under the Great Plains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

What are the effects of over pumping groundwater?

A

subsidence and salt water intrusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

salt water intrusion

A

when the water table is lowered the normal interface moves inland, allowing saline water to penetrate freshwater aquifers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

subsidence

A

the gradual caving in or sinking of an area of land, which can lead to sink holes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

What percent of water that we withdraw from rivers, lakes, and aquifers is not returned to these sources?

A

70%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

consumptive use

A

water does not return to its original source, instead it returns to a different stage in the hydrologic cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

nonconsumptive use

A

water is used and returned, and only temporarily removed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

What are seven issues related to freshwater use?

A
  1. climate change
  2. low water levels in lakes and rivers
  3. slow water flow
  4. pumping too fast from aquifers
  5. pollution (freshwater is contaminated)
  6. irrigation degrades soil
  7. thermal pollution
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

How do low water levels in lakes and rivers affect the economy?

A

low water levels can make navigation impossible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

How does slow water flow eliminate wetlands?

A

slow water flow causes deposition of sediments which fills streams, eliminating wetlands

104
Q

What is an effect of pumping water too fast from aquifers?

A

pumping water too fast causes a cone of exhaustion/depression, making the well unusable

105
Q

How does irrigation degrade soil?

A

evaporated water leaves dissolved minerals on the surface, causing salinization

106
Q

salinization

A

when the dissolved mineral remain on the top layer of soil, making it too salty for further agriculture

107
Q

How does climate change alter the freshwater supply?

A

climate change disrupts weather patterns, leading to more severe droughts or floods

108
Q

How does thermal pollution affect freshwater supplies?

A

industries and power plants release warm water into rivers, affecting dissolved oxygen

109
Q

In 2005, how many people lacked access to enough clean water for drinking, cooking, and washing according to the UN?

A

1 in 6 people

110
Q

What percent of the world’s population lives in river basins that do not have enough freshwater?

A

41%

111
Q

What are 5 consequences of not having access to freshwater?

A
  1. war
  2. less food, famine
  3. use of dirty water
  4. disease
  5. mass emigration/immigration
112
Q

What are 8 possible solutions to problems related to freshwater use?

A
  1. increase supply
  2. reduce domestic use
  3. closed system car washes
  4. grey water recycling
  5. irrigation (drought resistant crops, efficient irrigation methods)
  6. reduce pesticide/fertilizer use
  7. treat polluted or industrial water
  8. regulate maximum temperature of cooling water
113
Q

How would one increase freshwater supplies?

A

reservoirs, desalination plants, rainwater harvesting systems, artificially recharging aquifers

114
Q

What is one way we can reduce domestic water use?

A

low flow toilets

115
Q

ocean currents

A

the movement of water both vertically and horizontally

116
Q

Why is ocean water constantly sinking near the poles?

A

colder temperatures hold more salt and increase water density, so as a result of gravity water sinks

117
Q

What 2 factors affect ocean density?

A
  1. temperature
  2. salinity
118
Q

What happens to cold currents?

A

cold water that sinks crawls to the equator over the course of 100 years

119
Q

What do ocean currents play an important role in?

A

the global distribution of energy

120
Q

Coriolis effect

A

the effect that Earth’s rotation has on winds and ocean currents

121
Q

What percent of ocean currents are deep water currents?

A

90%

122
Q

What does the Coriolis effect cause?

A

deflection towards circular patterns

123
Q

In what direction do objects deflect as a result of the Coriolis effect in the northern hemisphere?

A

towards the right

124
Q

In what direction do objects deflect as a result of the Coriolis effect in the southern hemisphere?

A

towards the left

125
Q

How do surface currents get energy?

A

surface currents get energy from the friction between the wind and the ocean’s surface

126
Q

What are deep currents also called?

A

thermohaline currents

127
Q

What do warm currents do?

A

distribute heat from the equator towards the poles

128
Q

gyre

A

a large system of swirling ocean currents

129
Q

How many major ocean gyres are there?

A

5

130
Q

What is an example of a location in which warm currents flow from the equator to the poles?

A

the Gulf Stream (in the North Atlantic Ocean)

131
Q

What is the climate like near land close to seas?

A

mild, with moderate winters and cool summers

132
Q

What effect does water have on temperature?

A

it stabilizes it

133
Q

Why do water masses heat up and cool down more slowly than landmasses?

A

water has a higher specific heat capacity than land

134
Q

What effect does the Gulf Stream have on Northwestern Europe?

A

Northwestern Europe is warmer than it should be

135
Q

What current is the Namibian desert cooled by?

A

the Benguela current

136
Q

What does ENSO stand for?

A

El Niño Southern Oscillation

137
Q

teleconnections

A

changing conditions in one part of the world can affect areas far from the source

137
Q

Why do currents reverse during El Niño?

A

trade winds weaken (sometimes reverse), so there is nothing holding the water up

138
Q

What are 3 local effects of El Niño?

A
  1. collapse of anchovy fish stocks
  2. massive death of sea birds
  3. storms and flooding in the coastal plain of Peru
139
Q

upwelling

A

when cold nutrient-rich waters come up from the ocean depths as a result of wind blowing across the ocean surface

140
Q

How are ocean temperatures affected during El Niño?

A

ocean surface warms, sea surface temperatures are above average

141
Q

What effect does El Niño tend to have on rainfall?

A

rainfall increases over the Pacific Ocean, while it decreases over Indonesia

142
Q

How are ocean temperatures affected during La Niña?

A

ocean surface cools, sea surface temperatures are below average

143
Q

What effect does La Niña tend to have on rainfall?

A

rainfall decreases over the Pacific Ocean, while it increases over Indonesia

144
Q

What happens to trade winds during La Niña?

A

normal easterly winds along the equator become stronger

145
Q

How often do El Niño events occur?

A

every 2-8 years

146
Q

How long do El Niño events last?

A

about 2 years

147
Q

What are 6 examples of marine ecosystems?

A
  1. oceans
  2. mangroves
  3. estuaries
  4. lagoons
  5. coral reefs
  6. deep ocean floor
148
Q

What is the result of diversity in marine ecosystems?

A

stability and resistance

149
Q

continental shelf

A

the extension of continents under the seas and oceans

150
Q

What are 4 reasons why the continental shelf is important?

A
  1. over 50% of marine productivity but 15% of its area
  2. upwelling
  3. plenty of light reaches shallow seas so producers can photosynthesize
  4. countries can claim it as theirs to exploit and harvest
151
Q

What is the continental shelf also known as?

A

neritic zone

152
Q

benthic

A

live on or in the ocean floor

153
Q

pelagic

A

live in the water

154
Q

Since fish are not evenly distributed, where do most fish reside?

A

places with high productivity

155
Q

What percent of ocean primary productivity do phytoplankton produce?

A

99%

156
Q

phytoplankton

A

single-celled photosynthetic organisms

157
Q

zooplankton

A

single-celled animals that eat phytoplankton and their waste

158
Q

fishery

A

a fishery exists when fish are harvested in some way, it includes capture of wild fish, as well as aquaculture or fish farming

159
Q

What percent of fishery activity is in the ocean?

A

90%

160
Q

What percent of fishery activity is in freshwater?

A

10%

161
Q

How many people rely on fisheries for their livelihood?

A

up to half a billion people

162
Q

How many people get at least 20% of their protein from fish?

A

3 billion

163
Q

According to FAO (Food and Agriculture Organization of the United Nations), what percent of world’s fisheries are fully exploited, in decline, depleted, etc?

A

70%

164
Q

aquaculture

A

the farming of aquatic organisms in both coastal and inland areas involving interventions in the rearing process to enhance production

165
Q

Which 8 species of fish are all you need to meet your nutrient requirements?

A
  1. white sea bass
  2. walleye
  3. rainbow trout
  4. cobia
  5. arctic char
  6. yellowtail
  7. Atlantic salmon
  8. coho salmon
166
Q

What are 3 ways in which fish farming has become more sustainable?

A
  1. fishmeal (feed) uses more trimming and scraps (sometimes livestock and poultry waste) that would have just been discarded
  2. 8 species of fish can get one enough nutrients from alternative sources without eating other fish
  3. carp and catfish are grown within rice paddies (polyculture practice that integrates rice agriculture with aquaculture, so fish waste fertilizes plants)
167
Q

What are 4 negative impacts of fish farming?

A
  1. loss of habitat (sometimes Mangrove forests are removed for fish farms)
  2. pollution
  3. spread of diseases
  4. escaped species can become invasive or spread “GMO” genes
168
Q

The FAO estimates what percent of fisheries are under threat of overexploitation?

A

75%

169
Q

bycatch

A

unwanted fish and other marine animals that are thrown back into the ocean after being caught

170
Q

How are we so good at finding and catching fish? (3 ways)

A
  1. satellite and GPS technology of military quality
  2. large fishing fleets (boats used in the fishing industry) use modern refrigeration techniques to stay at sea for weeks
  3. indiscriminate fishing gear takes all organisms in an area, whether they are the target species or not
171
Q

How much fish is bycatch per year?

A

20 million tonnes

172
Q

What do bottom trawlers do to the ocean floor?

A

drag huge nets over the seabed virtually clearcutting it

173
Q

What are 6 fishing practices?

A
  1. longline
  2. purse seine
  3. bottom trawling
  4. drift net
  5. sonar
  6. planes
174
Q

longline fishing

A

placing very long lines with thousands of baited hooks

175
Q

purse seine fishing

A

a large net deployed around a school of fish that acts like a fence, and then a boat drives around it and pulls the strings tight

176
Q

What has purse seine fishing killed a large number of?

A

dolphins that live at the surface

177
Q

bottom trawling

A

use of a net dragging along the bottom of the ocean

178
Q

What is a side effect of bottom trawling?

A

bycatch

179
Q

What is comparable to bottom trawling?

A

clear-cutting forests

180
Q

How many dolphins, whales, turtles, and sharks are killed by drift nets?

A

10,000

181
Q

In 1992, the UN placed a ban on drift nets longer than what?

A

1.5 miles

182
Q

drift netting

A

nets hang vertically, and are kept upright by weights on the bottom and floats on the top

183
Q

sonar

A

uses sound waves to detect schools of fish

184
Q

How many tonnes of fish does the world catch per year?

A

just over 90 million

185
Q

How many tonnes of fish goes to fish meal to feed animals?

A

23 million

186
Q

In general, what percent of animal protein eaten by humans is fish?

A

15%

187
Q

What are 2 reasons why fish stocks are shrinking?

A
  1. industrialized countries subsidize (financially support) their modern fishing fleets by and estimated $50 billion per year
  2. demand is greater than supply
188
Q

Why do individuals tend to overexploit resources?

A

the advantage to taking the resource is greater than the cost to the individual

189
Q

What is often the solution to the “tragedy of the commons”?

A

regulation and legislation

190
Q

irrigation

A

any means used by humans to bring water to land

191
Q

When are irrigation methods used?

A

used when rainfall is either inconsistent/does not provide enough natural water to grow crops

192
Q

How much of the world’s land is irrigated?

A

about half

193
Q

How long have humans been using irrigation?

A

thousands of years

194
Q

What are the 3 most common types of irrigation?

A

flood (furrow), drip, spray

195
Q

How does excess water from irrigation/run off contribute to pollution?

A

run off carries dissolved salt and pesticide residues into local water supplies

196
Q

What is the percent efficiency for flood irrigation?

A

60%

197
Q

flood irrigation

A

when water is pumped/carried to fields and allowed to flow over the ground

198
Q

What is the percent efficiency for drip irrigation?

A

90-95%

199
Q

drip irrigation

A

when water is sent to crops through pipes that have holes in them, resulting in less salinization

200
Q

Which 2 irrigation methods are expensive to install?

A
  1. center-pivot
  2. drip irrigation
201
Q

Why does drip irrigation use 25% less water than flood irrigation?

A

less is lost to evaporation

202
Q

What is the percent efficiency for spray irrigation?

A

65%

203
Q

spray irrigation

A

when water is through pipes at high pressure though a nozzle that requires electricity and wastes a significant amount of water (evaporation/wind)

204
Q

What is the percent efficiency for LEPA (low energy precision application)?

A

95%

205
Q

LEPA (low energy precision application)

A

modified sprinklers that minimize wind and evaporation losses by running water directly onto the soil

206
Q

What is the percent efficiency for center-pivot irrigation?

A

80-95%

207
Q

center-pivot irrigation

A

low pressure spray that moves in a circle

208
Q

What are 8 ways to increase irrigation efficiency?

A
  1. soil moisture detectors
  2. mulching
  3. growing deep root plants
  4. import water intensive crops/meat
  5. line irrigation canals/ditches
  6. plastic covers over plants
  7. xeriscaping
  8. treat waste water for irrigation
209
Q

xeriscaping

A

using native vegetation/stones to decorate yard, reducing need for extra irrigation

210
Q

Why cover plants with plastic?

A

plastic traps moisture

211
Q

sustainable yield

A

the natural income that can be exploited each year without depleting the original stock or its potential for replenishment

212
Q

maximum sustainable yield

A

the highest amount that can be taken without permanently depleting the stock

213
Q

What are the 3 things that affect a species carrying capacity?

A
  1. the species reproductive strategy
  2. how long individuals live
  3. resources available in a habitat/ecosystem
214
Q

What are 3 reasons why harvesting the maximum sustainable yield still usually leads to population decline?

A
  1. predictions (in regards to the maximum sustainable yield) are not always accurate
  2. disease may strike/something else unaccounted for
  3. sex ratios may get thrown off
215
Q

When can the sustainable yield be harvested?

A

when the amount of individuals entering a population is greater than the amount of individuals leaving

216
Q

How does one calculate the sustainable yield?

A

SY = (annual growth and recruitment) - (annual death and emigration)

217
Q

optimal sustainable yield (OSY)

A

maximizes the revenue to cost ratio, has a much greater safety margin, and requires less effort

218
Q

What do fishing quotas usually set as?

A

a percentage of OSY (weight of catch not number of fish) per fleet per year

219
Q

water pollution

A

the contamination of bodies of water by pollutants either directly or indirectly

220
Q

What are the types of water pollution?

A

anthropogenic or natural, point source or non-point source, organic or inorganic, direct or indirect

221
Q

What are 4 examples of freshwater pollution?

A
  1. agricultural run off
  2. sewage
  3. industrial discharge
  4. solid domestic waste
222
Q

What are 5 examples of marine pollution?

A
  1. rivers
  2. pipelines
  3. the atmosphere
  4. human activities at sea
  5. discharge (both on purpose and accident
223
Q

anthropogenic pollution

A

created by human activites

224
Q

What is an example of natural pollution?

A

volcanic eruption

225
Q

What are 11 types of aquatic pollution?

A
  1. organic material
  2. inorganic plant nutrients
  3. toxic metals
  4. synthetic compounds
  5. suspended solids
  6. hot water
  7. oils
  8. radioactive material
  9. pathogen
  10. light
  11. noise
  12. invasive species
226
Q

BOD (Biological Oxygen Demand)

A

a measure of the amount of dissolved oxygen required to breakdown the organic material in a given volume of water through aerobic biological activity by microorganisms

227
Q

biotic index

A

indirectly measures pollution (on a scale of 1-10) by assaying the impact on species within the community according to their tolerance, diversity, and relative abundance

228
Q

indicator species

A

plant and animal species that show something about the environment by their presence, absence, abundance, or scarcity

229
Q

What effect does the “biodegradation” of organic material have on the BOD?

A

certain pollutant increase the BOD, leading to anoxic conditions

230
Q

Can warm or cold water hold less dissolved gases?

A

warm water can hold less dissolved gases than cold water

231
Q

eutrophication

A

when lakes, estuaries, and coastal waters receive inputs of nutrients which result in an excess growth of plants and phytoplankton

232
Q

What are the 6 steps of eutrophication?

A
  1. fertilizer runs off into a river/lake
  2. high nutrient levels makes algae grow faster (particularly phosphate)
  3. algal blooms form (mats of algae) that block out light to plants beneath them that die
  4. zooplankton and small animals at the surface feed on on algae, they are food to fish which multiply as there is more food so there are fewer plankton to eat the algae
  5. algae die and are decomposed by aerobic bacteria
  6. there is not enough oxygen in the water, so the food chain collapses
233
Q

What are the 5 effects of eutrophication?

A
  1. water ways are covered by green scum/duckweed
  2. give off smelling gases like hydrogen sulfide
  3. loss of biodiversity
  4. increased turbidity of water
  5. lack of oxygen
234
Q

Where do the high levels of nutrients come from during eutrophication? (5 things)

A
  1. detergents (major phosphate source)
  2. fertilizers
  3. livestock runoff
  4. sewage
  5. increased erosion of topsoil
235
Q

What are 3 strategies for managing eutrophication?

A
  1. altering human activity producing pollution
  2. regulating/reducing the pollutants at the point of emission
  3. clean up and restoration
236
Q

US Clean Water Act

A

sets standards for allowed levels of key water pollutants

237
Q

What is the goal of the US Clean Water Act?

A

maintain physical, chemical, biological integrity of the water

238
Q

Is the US Clean Water Act successful?

A

good for point source pollution, but needs to improve regulations for non-point source pollution

239
Q

preliminary treatment

A

a physical process that uses bar screens to remove large floating objects from raw sewage

240
Q

What objects does the bar screen remove during preliminary treatment?

A

non flushable tissues, sanitary products, corn, guns, and body parts

241
Q

primary sewage treatment

A

a physical process where the sewage moves to a large tank, slows down, giving solids time to settle; solids sink to the bottom and oils float to the top, and sludge is removed and sent to digesters

242
Q

secondary sewage treatment

A

a biological process in which aerobic bacteria remove biodegradable, oxygen demanding organic wastes

243
Q

aeration tank

A

removes organic materials and nutrients using bacteria; bacteria needs lots of oxygen because they are aerobic decomposers

244
Q

What are examples of organic wastes that aerobic bacteria remove during secondary sewage treatment?

A

human waste, soaps, detergents, food waste, e. coli, phosphates, nitrates

245
Q

plant effluent

A

water that leaves the plant

246
Q

Where is the sludge from primary sewage treatment disposed?

A

landfill, ocean, cropland, pasture, or rangeland

247
Q

Why is water after secondary sewage treatment chlorinated?

A

water is chlorinated to remove coloration and kill disease-carrying bacteria and some viruses (ex: e. coli, coliform, giardia, chlorea)

248
Q

advanced/tertiary sewage treatment

A

a chemical and physical process to remove nitrates and phosophates

249
Q

When is advanced/tertiary sewage treatment required?

A

only required if discharging into surface waters

250
Q

What is used as a disinfectant during advance/tertiary sewage treatment?

A

UV and sand for extra filtration

251
Q

What are other ways to clean/filter water?

A

charcoal, cloth, nano filters, boiling

252
Q

US Safe Drinking Water Act

A

requires the EPA to establish national drinking water standards

253
Q

The US Safe Drinking Water Act does not applied to bottled water, who regulates bottle water?

A

FDA

254
Q

maximum contaminant level

A

the maximum concentration of a chemical that is allowed in public drinking water systems

255
Q

In regards to the US Safe Drinking Water Act, what does the maximum contaminant level apply to?

A

any pollutant that may have adverse effects on human health

IB Environmental Science & Systems (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions