Download 6-6 Climate Change and Biodiversity 2.6.4a

Warmup
• Is anyone working to reduce the effects of
climate change?
• How can you reduce the effects of climate
change? (List at least 5 efforts)
Climate Change
and
Biodiversity
2.6.4a Analyze how changes in global temperatures affect
the biosphere (ex. Agriculture, species diversity, ecosystem
balance).
Golden Toad
Bufo periglenes
Once abundant in the cloud-shrouded rainforests of Monteverde in Costa
Rica, no one has seen one since 1989.
Harlequin Frogs
•About two-thirds of
Central and South
America's 110 harlequin
frog species are believed
to have vanished during
the 1980s and 1990s.
•The primary culprit is the
pathogenic chytrid fungus
Batrachochytrium
dendrobatidis, which has
been favored by global
warming.
Findings from the US Climate Change
Science Program
• Climate change is already affecting U.S. water
resources, agriculture, land resources, and
biodiversity, and will continue to do so.
•
http://www.sap43.ucar.edu/
Findings: Crops
• Grain and oilseed crops will mature more rapidly,
but increasing temperatures will increase the risk
of crop failures, particularly if precipitation
decreases or becomes more variable.
• Horticultural crops (such as tomato, onion, and
fruit) are more sensitive to climate change than
grains and oilseed crops.
Findings: Livestock
• Higher temperatures will negatively affect
livestock.
– Warmer winters will reduce mortality but this will
be more than offset by greater mortality in hotter
summers.
– Hotter temperatures will also result in reduced
productivity of livestock and dairy animals.
Findings:
Productivity
• Young forests on fertile soils will achieve higher
productivity from elevated atmospheric CO2
concentrations.
– Nitrogen deposition and warmer temperatures will
increase productivity in other types of forests where water
is available.
• The growing season has increased by 10 to 14 days
over the last 19 years across the temperate latitudes.
• Species’ distributions have also shifted.
Findings: Fire and
Invasive Species
• Forests in the interior West, the Southwest, and Alaska are
already being affected by climate change with
– increases in the size and frequency of forest fires,
– insect outbreaks and
– tree mortality.
• Weeds grow more rapidly under elevated atmospheric CO2.
– Under projections reported in the assessment, weeds migrate
northward and are less sensitive to herbicide applications.
• Invasion by exotic grass species into arid lands will result
from climate change, causing an increase fire frequency.
– Rivers and riparian systems in arid lands will be negatively
impacted.
Findings: Water
• Much of the United States has experienced higher
precipitation and stream-flow, with decreased drought
severity and duration, over the 20th century.
• The West and Southwest, however, are notable
exceptions, and increased drought conditions have
occurred in these regions.
• A continuation of the trend toward increased water use
efficiency could help mitigate the impacts of climate
change on water resources.
Findings: Water
Findings: Snow
• There is a trend toward reduced mountain
snowpack and earlier spring snowmelt runoff in
the Western United States.
• The rapid rates of warming in the Arctic observed
in recent decades, and projected for at least the
next century, are dramatically reducing the snow
and ice covers that provide foraging habitat for
polar bears.
Birds and Climate Change
• More is known about them
– not too many ‘fish-watchers’
– ‘canaries in the coal mine’
• 9787 known living species
– 21% (2,055 species) are extinction prone (for a
variety of reasons)
• habitat destruction/fragmentation impacts ~85%
• climate change is quickly emerging as a leading
factor
Being out of ecological synchrony
• Breeding is tied to seasonal events: flowering, seeds,
insect emergence, etc.
• Being out of step with food supplies may mean the
early bird doesn’t get the worm
• Species may be driven by different cues:
– birds by photoperiod (light)
– insects by temperature
What makes a species extinction prone?
• Specialists (vs Generalist)
– habitat
– food
– nesting requirements
– restricted range
• Importance to humans
• Predators, diseases, etc.
Can’t they just move?
• Many species rich areas are already protected,
e.g., national parks, nature preserves, etc.
– If vegetation changes, habitats are lost
– Where can they move to?
Ecological communities will be reshuffled
As species move they may have to deal with
changes in
– prey
– predators
– competitors
– parasites
– diseases
– habitats that are less than ideal
Case Study: Hawaiian Honeycreepers
Honeycreepers
• Once 29 species, now 19 due to habitat loss,
disease, predators
• Avian malaria, one agent, pushed their
distribution to altitudes where the mosquito
was rare
• 2ºC increase will reduce habitat by 50%, 96%,
and 100% in their three established refuges
Graphic Organizer
• Create a diagram summarizing the effects of
climate change on biodiversity.
• You may wish to include
– Pictures,
– Word web,
– Cause and effect chart, etc
• Once you finish, answer the two questions on
the bottom of your page.
Activity: Ecosystem Role Cards
• Read the four expected impacts of climate
change on your ecosystem
• Create a poster summarizing the impacts of
climate change on your ecosystem.
• Ex/Humans in Small Pacific Islands…
• Be sure it’s colorful and creative (more than
just words!)