Section 1: Abiotic Factors
 Abiotic Factors: “not” biotic factors, nonliving
 Name 4 from the pic.
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Air
Soil
Rocks
Water
Sunlight
Temperature
Climate
Atmosphere
 Air contains:
 78% Nitrogen
 21% Oxygen
 .03% Carbon Dioxide
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Needed for Photosynthesis. The process that
supports all life.
Water
 Essential for life on earth.
 Living organisms are 50-95% water.
 Water covers over 70% of earth’s surface, however:
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Over 97% of it is saltwater in the oceans.
Only 3% of the earth’s water is freshwater.
 68% of this water is locked in glaciers.
 30% is found in the ground
 Less than 0.3% of the freshwater on earth is in lakes, rivers,
swamps, and the atmosphere. AKA, usable water.
Soil
 Mixture of minerals, rock particles, decaying
organisms, water, and air.
 Abiotic because it is mostly rocks and minerals.
 Contains many biotic factors as well:
 Bacteria
 Fungus
 Insects
 Worms
Sunlight and Temperature
 Sunlight is the original source of energy for earth.
 Used in photosynthesis. Eventually supports all life.
 Temperature of a region is controlled by the sunlight.
 Latitude:
 The closer to the equator, the more direct sunlight a region
gets for more days per year.
 Elevation
 Lower temperature at higher elevations. Why?
 Air is thinner, therefore less molecules.
 Heat is the amount of energy that molecules have……..
Climate and Wind
 An area’s average weather conditions
 Temperature and Precipitation: 2 key components
 Influence the type of life that inhabits any ecosystem.
 Wind
 Also a result of the sun.
 Wind is caused when molecules in an area of the
atmosphere are heated.
Abiotic Factors influencing Biotic
Factors.
Biotic
Biotic
Biotic
Biotic
Biotic
Abiotic
Biotic
Section 2: Cycles in Nature
 The Water Cycle
 Nitrogen Cycle: What is Nitrogen?
 Important ingredient in proteins of life.
 Essential part of our DNA chain.
 The most plentiful gas in the atmosphere. (78%)
 Very few organisms can use N from the air.
 Nitrogen fixing bacteria in the soil form N compounds
that plants can use.
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These bacteria are found in the nodules (roots) of soybeans,
peas, and clover.
 Lightning also releases Atmospheric Nitrogen to the rain
and eventually soil to be used by plants. (5-8% )
The Nitrogen Cycle.
The Carbon Cycle
 A cycle of carbon atoms between the living and non-
living parts of the ecosystems.
Section 3: Energy Flow
 Photosynthesis vs. Chemosynthesis
 Photo: the use of light by plants to produce energy rich
molecules
 Chemo: the use of chemicals by bacteria to produce
energy rich molecules
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Deep sea ocean vents. No sunlight.
Food webs begin with bacteria, not plants.
Sulfur emitted by the volcanic vents is synthesized by the
bacteria into energy.
Energy Pyramid