BIOL 350 Final Exam Questions and Answers
1) The current state of civilization can be described in terms of problems of 'input'
or problems of 'output'. Describe the main current concerns associated with 'forests'
as a problem of 'input', and describe the main reasons why forests have important
value in terms of providing ecosystem services for humans. - ANSWER-Problems of
input:
-Deforestation; clearing forests for agriculture, urban expansion, mining, over-
harvesting for timber and paper production
-increased frequency of fire, drought, insect outbreaks
-clearing forests out faster than we can replace them
-world forest area shrunk by 80% per capita in past century
Value:
-"earth's lungs"; source of oxygen
-Earth's major source of water circulation; about 50% of the water that ends up in
the clouds for rain has been transpired by forests
-forests build and protect top soil; without forests we lose soil and minerals through
erosion
-major carbon sinks; capture, store, and decrease greenhouse carbon dioxide levels
(about 25% of carbon emitted by burning fossil fuels each year are absorbed by
forests)
-home to Earth's treasury of biodiversity
(2) World food production now appears to have peaked and prices are rising.
Describe the main reasons for this crisis that we discussed in BIOL350. - ANSWER-
Today's food shortages result from 4 critical long-term trends:
1) Rapid pop'n growth
-leads to over-plowing and over-grazing resulting in a loss of top soil
-increased demand for energy therefore increasing energy from fossil fuels which
contributes to global warming
-higher demand for food...causing food shortages
2)Loss of top soil
-because of deforestation, global warming, over-plowing...etc
3)Spreading water shortages
4)Rising temperatures and Global warming
-leads to rising sea level causing coastal flooding, which leads to loss of top soil
-higher temps also reduce crop yield
OTHER REASONS:
-arable land has peaked
-lost irrigation water from melting/dried up glaciers resulting from global warming
-rising energy prices
-more land being used to grow bio-fuels instead of crops
,-falling pollinator (bee) pop'ns from pesticide use and pollution
-over exploitation of fish
(3) The current state of civilization can be described in terms of problems of 'input'
or problems of 'output'. Describe the main current concerns associated with 'fossil
fuels' as a problem of 'input'. - ANSWER-problems of input:
-problem of supply and demand
-oil discoveries peaked in the 60s and since the 80s we have used more oil yearly
than we are discovering
-most things that we use require oil/natural gas to make (includes everything
plastic)
-rely on fossil fuels for transportation
-since the Great acceleration 5x more energy use (especially fossil fuels)
-turn to renewable resources like solar and wind energy but forget that a lot of
these alternate solutions depend on petro chemicals/fossil fuels to keep them
running; not durable, reliable, or completely safe
-2x more oil consumption in last 4 decades
-fossil fuels=non-renewable=definite supply
-contributes to global warming/climate change
4) The current state of civilization can be described in terms of problems of 'input'
or problems of 'output'. Describe the main current concerns associated with 'soil
loss' as a problem of 'input' - ANSWER-soil is one of the most precious and
threatened resources:
-arable land is disappearing...top soil is vital for maintaining the world's food supply
-it takes centuries to generate an inch of top soil even in a healthy ecosystem so
essentially it is a non-renewable resource
-soil degradation is especially high in dry lands due to salination from irrigation
-losing it from water erosion, wind, glacier melting (flooding) , deforestation
-loss of biodiversity from pesticide use; less biodiversity= more susceptible to
disease
MAIN PROBLEM OF OUTPUT= decreased capacity for food production
(5) Forecasters worry that climate change may disrupt the so-called 'global ocean
conveyer'. Describe what this is, how it might be disrupted, and what the main
consequences would be. - ANSWER-Global conveyer belt= a constantly moving
system of deep ocean circulation driven by temp/salinity; warm less salinated water
from gulf stream travels upward towards Europe in Atlantic and the wind over this
current picks up heat to warm Europe...this causes evaporation making the water
more salty which makes the water colder b/c it's more dense and sinks...downdraft
of heavy cold water generates south going stream
How is it disrupted?
-warming of arctic ice/Greenland ice sheet making the North Atlantic less salty
therefore surface currents aren't as warm, making Europe colder
Consequences:
-colder Europe= shorter growing season
-crop loss/less food production
, (6) Several forecasters have predicted that even if we completely stop all fossil fuel
burning tomorrow, it is too late to stop climate change. Describe the main reasons
why this may be so. - ANSWER--it will take an 80% decrease in carbon dioxide
emission by 2050 to stabilize atmospheric gas concentration
-feedback loops not in our favor; 1) increased levels of water vapour in the
atmosphere traps heat, leads to more evaporation of water vapour increasing the
amount of trapped heat, 2) loss of snow from global warming exposes more land
area which is less reflective then snow that the sun rays hit therefore absorbing
more heat because not as much snow covered surface to reflect,3) melting of
permafrost boreal regions released greenhouse gas methane into the atmosphere
-rising CO2 levels lead to ocean acidity which worsens global warming
-likely not possible to come up with an oil/gas alternative in time to; continue
providing the energy need to keep civilization running as we know it, further stop
climate change
-climate change due to increases in carbon dioxide concentration is largely
irreversible for 1000 years after emissions stop
-we have already "kick-started" an irreversible self-escalating series of natural
causes effecting global warming
(7) Many experts today believe that bio-fuel production causes more problems than
it solves. Describe the main reasoning behind this view. - ANSWER-bio-fuel
production causes loss of tropical forests and other natural habitats, depletes oil,
accelerates climate changes, exacerbates world hunger
-releases nitrous oxide
-countries fail to plan for cleaner energy
-these approaches do not help rising sea levels
-to grow biofuel crops, large scale forest burnings are needed to clear area
-farming biofuels releases nitrous oxide (climate change)
-biofuel from algae could create 4x the greenhouse gas
(8) The current state of civilization can be described in terms of problems of 'input'
or problems of 'output'. Describe the main current concerns associated with
'population' as a problem of 'output'. - ANSWER--population is estimated to reach 9
billion by 2050
-there are at least 1 billion people today that are severely malnourished/starving
-world population growth rate peaked in 1970; now it's slightly decreasing in
developed but increasing in underdeveloped countries
-high growth rates in developing countries and higher fertility rates in poorer
countries
-urban growth to mega-cities (cities of 10 million or more) ; how will they survive
the effects of climate change? increasing resource competition? decreasing
supplies/oil?
-there are now fewer farmers to feed the growing pop'n
-MALTHUSIAN DILEMMA; pop'n growth will outpace agricultural production ... too
many people, not enough food
-increased risk for disease outbreaks with larger pop'n
-unsustainable/ cannot provide adequate resources
1) The current state of civilization can be described in terms of problems of 'input'
or problems of 'output'. Describe the main current concerns associated with 'forests'
as a problem of 'input', and describe the main reasons why forests have important
value in terms of providing ecosystem services for humans. - ANSWER-Problems of
input:
-Deforestation; clearing forests for agriculture, urban expansion, mining, over-
harvesting for timber and paper production
-increased frequency of fire, drought, insect outbreaks
-clearing forests out faster than we can replace them
-world forest area shrunk by 80% per capita in past century
Value:
-"earth's lungs"; source of oxygen
-Earth's major source of water circulation; about 50% of the water that ends up in
the clouds for rain has been transpired by forests
-forests build and protect top soil; without forests we lose soil and minerals through
erosion
-major carbon sinks; capture, store, and decrease greenhouse carbon dioxide levels
(about 25% of carbon emitted by burning fossil fuels each year are absorbed by
forests)
-home to Earth's treasury of biodiversity
(2) World food production now appears to have peaked and prices are rising.
Describe the main reasons for this crisis that we discussed in BIOL350. - ANSWER-
Today's food shortages result from 4 critical long-term trends:
1) Rapid pop'n growth
-leads to over-plowing and over-grazing resulting in a loss of top soil
-increased demand for energy therefore increasing energy from fossil fuels which
contributes to global warming
-higher demand for food...causing food shortages
2)Loss of top soil
-because of deforestation, global warming, over-plowing...etc
3)Spreading water shortages
4)Rising temperatures and Global warming
-leads to rising sea level causing coastal flooding, which leads to loss of top soil
-higher temps also reduce crop yield
OTHER REASONS:
-arable land has peaked
-lost irrigation water from melting/dried up glaciers resulting from global warming
-rising energy prices
-more land being used to grow bio-fuels instead of crops
,-falling pollinator (bee) pop'ns from pesticide use and pollution
-over exploitation of fish
(3) The current state of civilization can be described in terms of problems of 'input'
or problems of 'output'. Describe the main current concerns associated with 'fossil
fuels' as a problem of 'input'. - ANSWER-problems of input:
-problem of supply and demand
-oil discoveries peaked in the 60s and since the 80s we have used more oil yearly
than we are discovering
-most things that we use require oil/natural gas to make (includes everything
plastic)
-rely on fossil fuels for transportation
-since the Great acceleration 5x more energy use (especially fossil fuels)
-turn to renewable resources like solar and wind energy but forget that a lot of
these alternate solutions depend on petro chemicals/fossil fuels to keep them
running; not durable, reliable, or completely safe
-2x more oil consumption in last 4 decades
-fossil fuels=non-renewable=definite supply
-contributes to global warming/climate change
4) The current state of civilization can be described in terms of problems of 'input'
or problems of 'output'. Describe the main current concerns associated with 'soil
loss' as a problem of 'input' - ANSWER-soil is one of the most precious and
threatened resources:
-arable land is disappearing...top soil is vital for maintaining the world's food supply
-it takes centuries to generate an inch of top soil even in a healthy ecosystem so
essentially it is a non-renewable resource
-soil degradation is especially high in dry lands due to salination from irrigation
-losing it from water erosion, wind, glacier melting (flooding) , deforestation
-loss of biodiversity from pesticide use; less biodiversity= more susceptible to
disease
MAIN PROBLEM OF OUTPUT= decreased capacity for food production
(5) Forecasters worry that climate change may disrupt the so-called 'global ocean
conveyer'. Describe what this is, how it might be disrupted, and what the main
consequences would be. - ANSWER-Global conveyer belt= a constantly moving
system of deep ocean circulation driven by temp/salinity; warm less salinated water
from gulf stream travels upward towards Europe in Atlantic and the wind over this
current picks up heat to warm Europe...this causes evaporation making the water
more salty which makes the water colder b/c it's more dense and sinks...downdraft
of heavy cold water generates south going stream
How is it disrupted?
-warming of arctic ice/Greenland ice sheet making the North Atlantic less salty
therefore surface currents aren't as warm, making Europe colder
Consequences:
-colder Europe= shorter growing season
-crop loss/less food production
, (6) Several forecasters have predicted that even if we completely stop all fossil fuel
burning tomorrow, it is too late to stop climate change. Describe the main reasons
why this may be so. - ANSWER--it will take an 80% decrease in carbon dioxide
emission by 2050 to stabilize atmospheric gas concentration
-feedback loops not in our favor; 1) increased levels of water vapour in the
atmosphere traps heat, leads to more evaporation of water vapour increasing the
amount of trapped heat, 2) loss of snow from global warming exposes more land
area which is less reflective then snow that the sun rays hit therefore absorbing
more heat because not as much snow covered surface to reflect,3) melting of
permafrost boreal regions released greenhouse gas methane into the atmosphere
-rising CO2 levels lead to ocean acidity which worsens global warming
-likely not possible to come up with an oil/gas alternative in time to; continue
providing the energy need to keep civilization running as we know it, further stop
climate change
-climate change due to increases in carbon dioxide concentration is largely
irreversible for 1000 years after emissions stop
-we have already "kick-started" an irreversible self-escalating series of natural
causes effecting global warming
(7) Many experts today believe that bio-fuel production causes more problems than
it solves. Describe the main reasoning behind this view. - ANSWER-bio-fuel
production causes loss of tropical forests and other natural habitats, depletes oil,
accelerates climate changes, exacerbates world hunger
-releases nitrous oxide
-countries fail to plan for cleaner energy
-these approaches do not help rising sea levels
-to grow biofuel crops, large scale forest burnings are needed to clear area
-farming biofuels releases nitrous oxide (climate change)
-biofuel from algae could create 4x the greenhouse gas
(8) The current state of civilization can be described in terms of problems of 'input'
or problems of 'output'. Describe the main current concerns associated with
'population' as a problem of 'output'. - ANSWER--population is estimated to reach 9
billion by 2050
-there are at least 1 billion people today that are severely malnourished/starving
-world population growth rate peaked in 1970; now it's slightly decreasing in
developed but increasing in underdeveloped countries
-high growth rates in developing countries and higher fertility rates in poorer
countries
-urban growth to mega-cities (cities of 10 million or more) ; how will they survive
the effects of climate change? increasing resource competition? decreasing
supplies/oil?
-there are now fewer farmers to feed the growing pop'n
-MALTHUSIAN DILEMMA; pop'n growth will outpace agricultural production ... too
many people, not enough food
-increased risk for disease outbreaks with larger pop'n
-unsustainable/ cannot provide adequate resources
