15.1 Life in the Earth System
KEY CONCEPT The biosphere is one of Earth’s four interconnected systems.
15.1 Life in the Earth System
The biosphere is the portion of Earth that is inhabited by life. What kinds of things would it include?
• The biosphere includes all ecosystems.– one of Earth’s systems
– includes the biota, all the living things in the biosphere
15.1 Life in the Earth System
• There are three other Earth systems.
– Hydrosphere—water, ice, and water vapor (Oceans, Rivers, Lakes, and groundwater)
– Atmosphere—air blanketing Earth’s solid and liquid surface
– Geosphere—geologic features above and below Earth’s surface
– Life has been found in all of these systems and virtually everywhere we have looked
15.2 Climate
KEY CONCEPT Climate is a key abiotic factor that affects the biosphere. How?
15.2 Climate
Climate is the prevailing weather of a region.
• Climate is the long-term pattern of weather conditions. What conditions would be included?– average temperature– precipitation– relative humidity
• Key factors shape an area’s climate.– temperature– sunlight– water– wind
15.2 Climate
• A microclimate is the climate of a small specific place within a larger area.
15.2 Climate
Earth has three main climate zones.
• The three main zones are the polar, tropical, and temperate climates. Which do we live in?– polar climate: the far northern
and southern regions ofEarth
– tropical zone: surrounds the equator
– temperate zone: the wide area in betweenthe polar and tropical zones
15.2 Climate
• The angle of the Sun’s rays determine an area’s climate.
temperatetemperate
polarpolar
tropicaltropical
temperatetemperate
polarpolar
90 N
15.2 Climate
• Earth’s tilt on its axis results in seasonal change.
• Solar heating causes movements in both water and air. Why?– wind– ocean currents
• Earth’s rotation also has effects on the winds and currents. How?
• The uneven heating of the Earth is the ultimate cause of all weather. Why?
15.2 Climate
• Mountains have an effect on climate. How?
western slope eastern slope
– Precipitation occurs on the side of the mountain facing the wind. Why?
– On the downwind side, drier and cooler air produce a rain shadow. Why?
15.3 Biomes
KEY CONCEPT Biomes are land-based, global communities of organisms.
15.3 Biomes
Earth has six major biomes.• A biome is a major community of organisms.
15.3 Biomes
• Tropical rain forest biomes produce lush forests. Why?
– warm temperature– abundant
precipitation all year
Source: World Meteorological Organization
15.3 Biomes
• Grassland biomes are where the primary plant life is grass.
Rapid City, South Dakota
Source: National Oceanic Atmospheric Administration
15.3 Biomes
– Temperate grasslands are dry and warm during the summer; cold in winter with most precipitation falls as snow.
• Grassland biomes are where the primary plant life is grass.
– Tropical grasslands are warm throughout the year, with definite dry and rainy seasons.
15.3 Biomes
• Desert biomes are characterized by a very arid climate. Why?– very low amount of
precipitation– four types: hot, semi-
arid, coastal, and cold
Tucson, Arizona
Source: National Oceanic Atmospheric Administration
15.3 Biomes
• Temperate forest biomes include deciduous forests and rain forests.– Temperate deciduous forests have hot summers and
cold winters.– Deciduous trees are the dominant plant species.
Source: National Oceanic Atmospheric Administration
Burlington, Vermont
15.3 Biomes
– Deciduous trees are the dominant plant species.– The temperate rain forests have a long wet season and
relatively dry summer.
• Temperate forest biomes include deciduous forests and rain forests.– Temperate deciduous forests have hot summers and
cold winters.
– Ferns and moss cover the forest floor.
15.3 Biomes
• The taiga biome is located in cooler northern climates.– boreal forest– long winters and short
summers– small amount of
precipitationSource: Environment Canada
Banff, Canada
15.3 Biomes
• The tundra biome is found in the far northern latitudes with long winters.– winter lasts 10 months– limited precipitation– permafrost
Barrow, Alaska
Source: National Oceanic Atmospheric Administration
15.3 Biomes
• Minor biomes, such as chaparral, occur globally on a smaller scale.
15.3 Biomes
Polar ice caps and mountains are not considered biomes.• Polar ice caps have no soil, therefore no plant community. • The climate and organisms found on mountains change as
the elevation changes.
15.3 Biomes
1. Which type of growth occurs when a population has unlimited resources and no predators?
• A. logistic growth • B. exponential growth • C. S-shaped growth • D. population crash
15.3 Biomes
Which type of growth occurs when a population has unlimited resources and no predators?
• A. logistic growth • B. exponential growth • C. S-shaped growth • D. population crash• Correct Answer = B
Which of the following can cause a population crash? • A. a rise in the carrying capacity for a population • B. a rise in the emigration rate • C. a drop in the immigration rate • D. a drop in the carrying capacity for a population
15.3 Biomes
Which type of growth occurs when a population has unlimited resources and no predators?
• A. logistic growth • B. exponential growth • C. S-shaped growth • D. population crash• Correct Answer = B
Which of the following can cause a population crash? • A. a rise in the carrying capacity for a population • B. a rise in the emigration rate • C. a drop in the immigration rate • D. a drop in the carrying capacity for a population• Correct Answer = D
15.3 Biomes
Review
• The biosphere is the part of Earth that contains all living things and includes all the ecosystems.
• Climate is the prevailing weather over an area• The uneven heating of the Earth due to its shape, tilt and
rotation determines weather.• The Earth has six major biomes:
– Tropical Rainforest– Grasslands– Desert– Temperate forest– Taiga– Tundra