Change in the Biosphere

Changes in the Lithosphere 3.1

About 4.6 Billion years

Humans have been around for about 100,000 years

Tectonic plates

Liquid rock below the surface rises through the cracks between the plates in the ocean floor.

As the new rock forms it pushes the tectonic plates apart.

Other factors that shape the land

Weathering ~breaking down of rocks by weather or water

Erosion~ broken-down material is then carried off

Changes in the Hydrosphere

Ice Ages

• Long period of cooling• Huge ice masses form and extend from the

Earth’s polar regions.• They covered much of the planet’s surface

Glaciers

After the ice age the glaciers melt.

Ice age = lower sea levelsAfter ice age = rise in sea levels

5 major ice ages most recent was 10,000 – 12,000 years ago

What causes a glacier to form and melt?

El Niño• Warm, nutrient-poor water flows southward along the coast

of South America. • Every year around December for a few weeks• When it lasts for several months we call it El Niño• Effects climate and economics. How?

• Change in water temp and nutrient content affect survival of fish• Less fish in water = less fish to catch• Less fish means less fish byproduct (fish meal) = food for poultry

Changes in the Atmosphere• Changes in the Earth’s atmosphere have resulted from organic and

volcanic activities

Before LifeAtmosphere consisted of gases like water vapor, carbon dioxide and sulfur. (volcanic eruptions)

Organisms evolved that could combine H2O, CO2 and sunlight to produce food

Photosynthesis - - - > Oxygen into atmosphere

O2, H2O vapor, CO2 and N have been cycling in the atmosphere and organisms for about 3.5 billion years

Some of the Earth’s carbon is being stored in the bodies of living and dead organisms. (Fossil Fuels)

Burning releases Carbon into the atmosphere and May influence the temperature of Earth

Greenhouse Effect. (Human impact)Loss of OzoneIncreased pollution of troposphere

Volcanoes (Natural impact)

Greenhouse effect Ozone Layer

Needs of Organisms 3.2• Depend on the environment for everything they need to live• Common needs of Organisms

• Water• Energy• Living space• Suitable climate

• The specific needs of an organism define the environment in which it must live and its role in the ecosystem

Water

• Presence of fresh water is one of the most important factors in the ability of land to support life.• Needed for

• Plants to grow• Plants and water are both needed for animals to survive

• Amount of rainfall directly affects the life in the area. How?

• What about fish?• Affected by water quality.

• Temp, nutrients, dissolved oxygen other chemicals • Factors interact and could cause issues

Food and Energy

• Almost all the energy used by living things comes from • Photosynthesis • Plants and algae makes food

• Animals and other organisms eat plants

• All the substances that an organism requires from food are called nutrients.• Obtain by ingesting food through mouth• Absorb the nutrients (fungi, protists, plants and some animals• Poisons

Living SpacePlants need space to get enough sunlight and spread their roots

Animals need space • Seek food• Water• Shelter• Mates

Territory~ an area that is claimed as a living space by an individual or group of animals.Size is determined by the needs of the animal

Climate

• Most organisms can only survive within a certain range of temperatures (cold-blooded)• Organisms can go Dormant • Growth slows or stops and plants may loose their leaves

• Why do we use refrigerators?• (Warm- blooded) wider range of temp tolerance and can remain

active in diverse climate• Uses lots of energy

• Some animals go into a state of hibernation • Energy consumption slows (lowered metabolism)

The Ecosystem 3.3• It is a highly organized structured environment in which all parts exist

in a delicate balance.

Individual species

Entire ecosystem

Species• A group of organisms so similar to one another that they can breed

and produce fertile offspring.• similar needs such as • range of climate• size of territory often compete for resources• types of foods

A specific environment in which a particular species lives is its habitat.

Find appropriate:Food

ShelterTemperatures

Other factors needed

Destruction of habitat is a serious threat.

Geographical range is the area in which a species can livedepends on available sustainable habitat

Polar Bear RangeMountain Lion Range

Population and CommunitiesAll members of a species that live

in the same geographic area

All the different populations that live and interact in the same area

An Ecosystem includes all the communities in an area, as well as abiotic factors in the environment.