Ch 56 Biodiversity and Global Change Flashcards Preview

BIOL 172 > Ch 56 Biodiversity and Global Change > Flashcards

Flashcards in Ch 56 Biodiversity and Global Change Deck (72):
1

Conservation biology

Seeks to preserve life

2

Several fields that are integrated into several fields

1) Ecology
2) Physiology
3) Molecular biology
4) Genetics
5) Evolutionary biology

3

Three main components of biodiversity

1) Genetic diversity
2) Species diversity
3) Ecosystem diversity

4

1)___ ___ are concerned about 2)___ ___ because of alarming statistics regarding 3)___ and 4)___

1) Conservation biologists
2) Species lost
3) Extinction
4) Biodiversity

5

Global extinction rates of birds

12%

6

Global extinction rates of mammals

21%

7

Global extinction rates of amphibians

32%

8

Extinction may be 1)___ or 2)___

1) Local
2) Global

9

Species related to 1)___ ___ can have important 2)___ qualities

1) Agricultural crops
2) Genetic

10

Ecosystem services

Encompass all the processes through which natural ecosystems and their species help sustain human life

11

Examples of ecosystem services

1) Purification of air and water
2) Detoxification and decomposition of wastes
3) Cycling of nutrients
4) Moderation of weather extremes

12

Four major threats related to most species' extinctions

1) Habitat destruction
2) Introduced species
3) Over-harvesting
4) Global change

13

What is the greatest threat to biodiversity throughout the biosphere?

Human alteration of habitat

14

In almost all cases, what leads to loss of biodiversity?

1) Habitat fragmentation
2) Habitat destruction

15

Without their native 1)___, 2)___, and 3)___, introduced species may spread rapidly

1) Predators
2) Parasites
3) Pathogens

16

What happens when introduced species gain a foothold in a new habitat?

They usually disrupt their adopted community

17

Over-harvesting

Human harvesting of wild plants and animals at rates exceeding the ability of populations of those species to rebound

18

What kind of organisms are especially vulnerable to over-harvesting?

Large organisms with low reproduction rates

19

Over-fishing

Occurs when fishing activities exceed the capacity of fish populations to maintain themselves

20

Over ___ of all fisheries are now fully exploited

Half

21

Fish and other marine organisms account for ___-___ of total global income of animal protein

13% to 17%

22

What occurred in the 1990's in regard to global fishing harvests?

Global fish harvests reached a plateau

23

What was the maximum global fish harvest?

~86 million tons

24

During the 1990's what fishery collapsed?

The cod fishery off of Newfoundland

25

Bycatch

Species of fish that are harvested, but are not of the targeted fishery

26

Bycatch includes:

1) Fish
2) Crustaceans
3) Birds
4) Sea turtles
5) Dolphins
6) Whales

27

___ of some fisheries is bycatch

80%

28

What is a common means of harvesting large predators?

Longlines

29

1)___ ___ such as sharks are directly targeted or depleted through 2)___ ___

1) Top predators
2) Bycatch mortality

30

Due to bycatch, what percentage of large, predatory fish stocks are gone?

90%

31

Many deep sea fish are at risk due to slow 1)___ and low 2)___ ___

1) Growth
2) Reproductive rates

32

Some deep sea fish that are at risk:

1) Orange roughy
2) Sablefish
3) Cods

33

How long does it take many deep sea fish to reach breeding maturity?

30 to 40 years

34

Individual Transferable quotas (ITQs)

Consists of limited access permits to harvest quantities of fish

35

Two methods of aquaculture (fish farming):

1) Closed inland enclosures in which foods and wastes do not immediately enter natural ecosystems

2) Open pens in which foods and wastes can enter natural ecosystems

36

On a 1)___ ___, aquaculture can be 2)___ damaging than fisheries based on catch from wild populations

1) Local scale
2) More

37

Human-caused environmental changes include:

1) Nutrient enrichment
2) Toxin accumulations
3) Climate change
4) Ozone depletion

38

What do ocean currents transport?

1) Nutrients
2) Wastes
3) Heat

39

The 1)___ ___ keeps 2)___ much 3)___ than other regions at the same latitude

1) Gulf Stream
2) Europe
3) Warmer

40

In the 1)___ ___, warm surface waters are normally pushed 2)___ by 3)___ ___ ___

1) Pacific Ocean
2) West
3) Equatorial trade winds

41

What does the movement of warm surface waters of the Pacific Ocean to the west cause?

1) Heavy precipitation in southeast Asia
2) Upwelling of nutrient waters along the Americas

42

El Nino

Occurs when the rising air currents weaken, and westward wind and ocean currents fail

43

How often does an El Nino occur?

Every 3 to 5 years

44

Two common characteristics of El Nino years:

1) Intense storms in the Americas

2) Droughts in the west Pacific

45

What occurs in Hawaii during an El Nino year?

Drought during Hawaii's rainy season is more common

46

When is Hawaii's rainy season?

October to March

47

What appears to be worsening El Nino?

Global warming

48

Greenhouse effect

CO2, water vapor, and other greenhouse gases reflect infrared radiation back toward Earth

49

What is important for keeping Earth's surface at a habitable temperature?

The greenhouse effect

50

Increasing concentrations of atmospheric 1)___ is linked to increasing 2)___ ___

1) CO2
2) Global temperature

51

When was the greenhouse effect first recognized?

1827

52

From what can climatologists make inferences about the past?

1) Pollen and fossil plant records
2) CO2 levels (inferred from bubbles trapped in glacial ice)
3) Analysis of past temperatures (inferred from chemical isotope analysis)

53

With what does CO2 fluctuate?

Seasonal changes in photosynthesis and respiration

54

How much does CO2 usually change?

5 to 7 ppm

55

B 2009, atmospheric 1)___ levels had reached 2)___

1) CO2
2) 338 ppm

56

Atmospheric CO2 levels n 2009 were higher than what? By how much?

1) 39% higher than before the Industrial Revolution
2) Higher than the past 800,000 years

57

Burning fossil fuels release 1)___ ___ ___ of 2)___ to the air

1) 8 billion tons
2) C/year

58

Oceans and forests act as 1)___ ___ and absorb 2)___

1) Carbon sinks
2) 4.7 GtC/year

59

Where are the lowest emissions in the world?

In Chad

Per capita production is one-thousandth that of the US

60

Global warming projections vary between 1)___-___ within the 2)___

1) 2C to 4C
2) Century

61

What could stop circulation of deep seas?

Dilution of salt water by melting polar caps

62

Heinrich events

Slowing or ceasing of the circulation of the deep seas

63

If a Heinrich event occurs, what might the results be?

1) The ocean's thermal conveyor system will shift south
2) Climate will cool in a few decades

64

What can slow global warming?

1) International reduction in energy need
2) Conversion to renewable energy sources
3) Reduced deforestation

65

What protects life on Earth from the damaging effects of UV radiation?

A protective layers of ozone molecules (O3)

66

Since when may the ozone layer have been gradually thinning?

The mid-1970s

67

What is the main cause of the destruction of atmospheric ozone?

Chlorofluorocarbons (CFCs) produced by human activity

68

What reaction decreases the amount of ozone in the atmosphere?

Chlorine (contained in CFCs) and ozone's reaction, which produces O2

69

What is linked to increased UV radiation (due to ozone depletion)?

1) DNA damage
2) Poorer phytoplankton growth

70

Ozone levels have decreased 1)___-___ at 2)___ during the past 20 years

1) 2% to 10%
3) Mid-latitudes

71

Where is the ozone layer thinnest?

Over Antarctica

72

What has decreased ozone deplection?

An international agreement signed in 1987 to halt CFC emissions