Abiotic Factors Chapter 25, Section 1. Environmental Factors Biotic Factors Biotic Factors Features of an environment that are alive or were once alive.

Abiotic FactorsAbiotic Factors

Chapter 25, Section 1Chapter 25, Section 1

Environmental FactorsEnvironmental Factors Biotic FactorsBiotic Factors Features of an environment that Features of an environment that

are alive or were once alive.are alive or were once alive.

Environmental FactorsEnvironmental Factors Abiotic FactorsAbiotic Factors Nonliving factors in an Nonliving factors in an

environment.environment.– Include:Include:

air, water, soil, sunlight, temperature, air, water, soil, sunlight, temperature, and climate. and climate.

– Often determine which organisms Often determine which organisms can live in the environment.can live in the environment.

AirAir AtmosphereAtmosphere Air that surrounds the EarthAir that surrounds the Earth

– Contains:Contains: 78% nitrogen78% nitrogen 21% oxygen21% oxygen 0.94% argon0.94% argon 0.03% carbon dioxide0.03% carbon dioxide Traces of other gasesTraces of other gases

– Air is very important as most Air is very important as most organisms need either oxygen or organisms need either oxygen or carbon dioxide to live carbon dioxide to live (photosynthesis and respiration).(photosynthesis and respiration).

WaterWater WaterWater Many life processes, such as Many life processes, such as

photosynthesis, respiration, and photosynthesis, respiration, and digestion require water.digestion require water.– In fact, most organisms are 50% to In fact, most organisms are 50% to

95% water.95% water.

Environments that have more Environments that have more water usually support a greater water usually support a greater diversity of and a larger number diversity of and a larger number of organisms.of organisms.

SoilSoil SoilSoil Mixture of minerals, rocks, living Mixture of minerals, rocks, living

and dead organisms, water, and and dead organisms, water, and air.air.– Humus - Decaying matter found in Humus - Decaying matter found in

soil. soil.

Soil has an impact on the types Soil has an impact on the types of plants that can grow in an of plants that can grow in an environment.environment.

SunlightSunlight SunlightSunlight Main energy source in an Main energy source in an

environment.environment.– Used by producers to make food Used by producers to make food

(sugars).(sugars).– Transferred to consumers when Transferred to consumers when

producers are eaten.producers are eaten.

TemperatureTemperature TemperatureTemperature Depends on the amount of Depends on the amount of

energy received from the sun energy received from the sun – Amount of energy received depends Amount of energy received depends

on the latitude and elevation of the on the latitude and elevation of the area.area.

Most organisms must maintain a Most organisms must maintain a body temperature between 0 and body temperature between 0 and 50 degrees Celsius in order to 50 degrees Celsius in order to survive.survive.

TemperatureTemperature LatitudeLatitude Determines the amount of energy Determines the amount of energy

received by the sun.received by the sun.– Sunlight strikes the Earth directly at Sunlight strikes the Earth directly at

the Equator resulting in large the Equator resulting in large amounts of energy and high amounts of energy and high temperatures.temperatures.

– Sunlight strikes the Earth at the Sunlight strikes the Earth at the poles at an angle resulting in smaller poles at an angle resulting in smaller amounts of energy and low amounts of energy and low temperature.temperature.

TemperatureTemperature ElevationElevation Air molecules in the atmosphere Air molecules in the atmosphere

trap heat from the sun and serve trap heat from the sun and serve as a layer of insulation for the as a layer of insulation for the Earth.Earth.

Because more air molecules are Because more air molecules are at sea level than are at high at sea level than are at high elevations temperature elevations temperature decreases with increasing decreases with increasing elevation.elevation.

ClimateClimate ClimateClimate The average weather conditions The average weather conditions

in an area.in an area.– Includes temperature, precipitation, Includes temperature, precipitation,

and wind.and wind.

ClimateClimate WindWind Movement of air particles from Movement of air particles from

areas of high pressure (cold) to areas of high pressure (cold) to areas of low pressure (warm)areas of low pressure (warm)

ClimateClimate Rain Shadow Rain Shadow

EffectEffect When air reaches a mountain it is When air reaches a mountain it is

forced upward.forced upward. As the air rises, it cools and As the air rises, it cools and

releases any moisture it contains.releases any moisture it contains. By the time the air reaches the By the time the air reaches the

far side of the mountain it is far side of the mountain it is relatively dry.relatively dry.