Transcript Local Conditions - North Mac Schools

Interest Grabber
Section 4-1
Discussion
Local Conditions
How would you describe your climate, or the average, year-after-year conditions of
temperature and precipitation where you live?
Does your area receive a great deal of precipitation—rain and snow—or is your area
very dry?
What is Climate?
• Weather – day-to-day condition of Earth’s atmosphere
• Climate – average of daily weather over a period of time
•Factors affecting climate:
• Trapping of heat by the atmosphere
• Latitude
• Ocean currents
• Etc.
The Greenhouse Effect
Section 4-1
Sunlight
Some heat
escapes
into space
Greenhouse
gases trap
some heat
Atmosphere
Earth’s surface
Greenhouse Gases
Include:
• CO2 (Carbon dioxide)
• Methane
• Water vapor
• Similar to a car on a hot day, glass allows light energy in,
yet little heat escapes.
The Effect of Latitude on Climate
•Earth is tilted on it’s axis, causing varying degrees of light striking the Earth.
3 main zones of climate:
1. polar zones – sun strikes Earth at a very low angle
2. temperate zones – angle of the sun varies
3. tropical zones – direct or near direct sunlight
Figures 4-1 and 4-2 Heating of the Earth’s Surface
and Some Factors That Affect Climate
Section 4-1
Greenhouse Effect
Different Latitudes
90°N North Pole
Sunlight
Sunlight
Some heat
escapes
into space
Greenhouse
gases trap
some heat
Arctic circle
Sunlight
Most direct sunlight
66.5°N
Tropic of Cancer
23.5°N
Equator
0°
Tropic of Capricorn
23.5°S
Sunlight
Atmosphere
Arctic circle
Earth’s surface
Sunlight
66.5°S
90°S South Pole
Section Outline
Section 4-2
4–2 What Shapes an Ecosystem?
A. Biotic and Abiotic Factors
B. The Niche
C. Community Interactions
1. Competition
2. Predation
3. Symbiosis
D. Ecological Succession
1. Primary Succession
2. Secondary Succession
3. Succession in a Marine Ecosystem
Biotic factors
• Living or
once living
Abiotic
• Non-living components that influence an ecosystem
• Temperature, Type of soil, Precipitation, Climate
Abiotic and Biotic Factors
Section 4-2
Together they determine the stability
of an ecosystem
Abiotic Factors
Biotic Factors
ECOSYSTEM
The Niche
• Where an organism fits into its environment
– Place on food chain
What it eats and what eats it
– How and where it reproduces
– Climate it prefers
• No two species can occupy the same niche in the
habitat! Competition? One wins and one loses.
same
Figure 4-5 Three Species of Warblers and
Their Niches
Section 4-2
Cape May Warbler
Feeds at the tips of branches
near the top of the tree
Bay-Breasted Warbler
Feeds in the middle
part of the tree
Spruce tree
Yellow-Rumped Warbler
Feeds in the lower part of the tree and
at the bases of the middle branches
Community Interactions
1.Competition – species attempt to use an ecological resource in the same place at
the same time.
2.Predation – one organism captures and feeds on another organism
3.Symbiosis – relationship when 2 species live together
• Mutualism – helps both
• Commensalism – one benefits, other not harmed
• Parasitism – one lives on or in another, harming the host.
Ecological Succession
• Ecosystems are constantly changing in response to human or non-human
interactions.
• Could be a rapid change or very gradual (thousands of years).
• Types:
• Primary
• Secondary
Primary Succession
•Occurs where no soil exists – must start with plants….Why?
• Bare rocks
• Volcanic areas
• Occurs often due to climatic changes of plate tectonics
• After original pioneer species establish area, new organisms
begin to inhabit area.
Primary succession
after an eruption
Primary
succession
Secondary Succession
• When a drastic climatic event disturbs a particular area and
organisms re-establish the ecosystem over time.
• Prairie fires
• Ecosystems typically bounce back from natural
disturbances, but struggle to return when human
disturbances occur (non-natural).
Secondary succession
after clear-cutting or
a fire.
Secondary
succession