THE BIOSPHERE: ANINTRODUCTION TO EARTH'SDIVERSE ENVIRONMENTS

Ecologists study how organisms interact with their environment at several levels. 1. Organism

Individual organisms interacting with the environment

2. Population Group of individuals of the same species living in a

particular geographic area 3. Community

All the populations of different species that inhabit a particular area

4. Ecosystem All the biotic and abiotic components in a certain

area Landscapes - array of ecosystems

The biosphere is the total of all of Earth‘s ecosystems. The biosphere is the global ecosystem. It extends from

an altitude of several kilometers to 3,000 m beneath Earth's surface to a depth of several kilometers in the

oceans The biosphere is self-contained and

characterized by patchiness.

Physical and chemical factors influence life in the biosphere Major abiotic factors determine the

biosphere's structure and dynamics

The Earth’s tilt causes the seasons

– The seasons of the year result from the permanent tilt of the plant on its axis as it orbits the sun

https://www.youtube.com/watch?v=O9hawBb3wbk

Disturbances such as fire, hurricanes Temperature and Wind

Regional climate influences thedistribution of biological communities

Because of its curvature, Earth receives an uneven distribution of solar energy

The tilt of the Earth's axis causes the seasons of the year Globe's position relative to the sun changes through the

year The tropics experience the least seasonal variation in

solar radiation

Uneven heating causes rain and winds The direct intense solar radiation near the equator has an

impact on the global patterns of rainfall and winds The tropics experience the greatest annual input and least

seasonal variation in solar radiation

Uneven heating of the Earth sets up patterns of precipitation and prevailing winds.

https://www.youtube.com/watch?v=Ye45DGkqUkE

https://www.youtube.com/watch?v=i2mec3vgeaI

Ocean currents have a profound effect on regional climates.

Generally modify climate of nearby land Landforms can also affect local climate Variations in climate determine the

character of the world's biomeshttp://gpb.pbslearningmedia.org/resource/ttv10.sci.ess.watcyc.currents/the-role-of-ocean-currents-in-climate/

http://earth.nullschool.net/#current/wind/surface/level/orthographic=-75.00,0.00,247

Organisms are adapted to abiotic and biotic factors by natural selection.

Species exist in a given place because they evolve there or disperse there.

Unique adaptations that fit a particular environment allow organisms to survive there.

Organisms vary greatly in their ability to tolerate fluctuations and long-term changes in their environment.

The global water cycle connects aquatic and terrestrial biomes.

CONNECTION: The science of ecology provides insight into environmental problems.

Human activities affect all parts of the biosphere

– Cities, farms, and highways change the landscape

– The widespread use of chemicals such as fertilizers and pesticides poses problems to people and other organisms.

AQUATIC BIOMES: Oceans occupy most of Earth's surface Abiotic factors influencing the distribution

of aquatic biomes Light Distance from shore Availability of nutrients

Estuaries are productive areas where rivers meet the ocean

– The saltiness of estuaries ranges from less than 1% to 3%

– They provide nursery areas for oysters, crabs, and many fishes

– They are often bordered by extensive coastal wetlands

– Among the most productive biomes

Freshwater biomes include lakes, ponds, rivers, streams, and wetlands

Terrestrial biomes reflect regional variations in climate Tropical forests cluster near the equator

Savannas are grasslands with scattered trees

Deserts are the driest terrestrial biomes

The chaparral is a region of dense, spiny shrubs with tough, evergreen leaves

Temperate grasslands include the North American prairie

Broadleaf trees dominate temperate forests

Coniferous forests are often dominated by a few species of trees

Arctic tundra is a treeless biome.