Transcript Global Climate Change

CONSERVATION ECOLOGY
Objectives:
• I will be able to discuss how human activity is changing the
Earth.
• I will be able to discuss the value of biodiversity.
• Human activities threaten Earth’s biodiversity
• Biodiversity has three main levels:
– Genetic diversity,
– Species diversity,
– Ecosystem diversity.
• Major threats to biodiversity:
– Habitat loss,
– Invasive species,
– Overharvesting,
– Global change (acid precipitation, climate change, air
pollution, etc.).
Loss of biodiversity:
• Minimizes the chance of survival when faced with large
environmental changes.
• Decreases stability of the ecosystem (in nature “everything is
connected”).
• Poses ethical concerns.
• Earth is changing rapidly as a result of human action.
Common environmental problems:
Eutrophication
• Refers to an excessive amount of nutrients in a body of water
caused by runoff of nutrients from the land.
• Causes overgrowth of algae.
• Penetration of light is diminished which leads to decreased
photosynthesis and decreased oxygen.
• When algae die, algal decomposers consume oxygen, further
decreasing amount of oxygen available for animals.
Deforestation
= conversion of forest to non-forest.
• Especially high in tropical rainforest.
• Due to logging, agriculture, urbanization, mining, oil
exploitation, etc.
Ozone Depletion
• Ozone layer (in stratosphere)
absorbs most of sun’s harmful UV
radiation.
• Caused by chlorofluorocarbons
(CFCs).
Pollution
• Present in water (fresh, ocean, ground water), land, air.
• Caused by pollutants from industry/automobiles and by
nonbiodegradable wastes which cannot be broken down by
natural processes.
Biological Magnification
• Toxins become more
concentrated in successive
trophic levels.
• The toxins cannot be
broken down by normal
chemical means, so they
magnify in concentration as
they move through the
food chain.
Acid Precipitation
• Due to air pollutants (sulfur dioxide and nitrogen oxide) which
increase the acidity of the rain.
• Damages plant tissues, leaches minerals from soil, causes death
of trees, ruins stone buildings, kills zooplankton .
Global Climate Change
• Due to the
greenhouse effect =
heat retention by
atmospheric gases
such as CO2 and
methane.
• Global temperatures
and sea levels are
rising.
• Weather patterns are
affected.
• Species are
threatened.
What positive effects do we
have on the environment?
Math Connection
Energy Flow in a Hardwood Forest (kJ/m2)
Reflected
4.3 X 105
Energy Lost
1.4 X 106
Absorbed
1.5 X 106
Solar Radiation
2.5 X 106
Transmitted
6.4 X 105
Energy Accumulated
As Biomass
1.9 X 104
Tree Layer
1.3 X 104
Shrub Layer
?
Herb Layer
1.1 X 103
What percent of the biomass in the forest community
represented above is tied up in the shrub layer? Give your
answer to the nearest whole number.