The study of the interactions that take place among organisms

and their environment

Biosphere

• The part of Earth that supports life–Top portion of Earth's crust–All the waters that cover Earth's

surface–Atmosphere that surrounds Earth.

Factors that affect the biosphere may be living or nonliving

Biotic Factors: living such as plants animals, bacteria fungus, Abiotic Factors: nonliving such as soil, sun, water air, temperature Name the biotic and abiotic factors in this picture

Ecosystem

• All the organisms living in an area and the nonliving features of their environment

Habitat

• The place in which an organism lives –provides the kinds of food and shelter,

proper temperature, and the amount of moisture the organism needs to survive

NICHE• A niche is the role an organism or population

plays within its community or ecosystem

It includes all the relationships that an organism (or population) has with its environment and with other organisms and populations in its environment.

Population

All the organisms in an ecosystem that belong to the same species

Community

All the different populations that live within an ecosystem

Limiting Factor

Anything that restricts the number of individuals in a population.

Includes living and nonliving features of the ecosystem

Carrying Capacity• The largest number of individuals of a

particular species that an ecosystem can support over time.

• It can be changed by nature or humans.

Competition

For Food and Space Competition caused by population growth affects

many organisms, including humans Limits population size

Counting PopulationsRANDOM SAMPLES

•Make a GRID

•Count the total number of squares in the grid

•Choose one square of the grid at random.

•Count the population in that one square.

•Estimate the total population by multiplying the number in one square time the total squares in the grid.

ACTUAL COUNT

• Each member of a population is counted one by one

Name of Population

Ducks Cattails Water Lilies

Actual Count

6 20 4

Sample Count

Relationships• Producers, such a s plants, use the sun to make

food.• Most of the energy they use for themselves.

• Consumers that eat producers to get energy: are First Order Consumers (herbivores)

• A consumer that eats another consumer for energy is a Secondary Consumer (carnivore or scavenger)

• A consumer that eats a secondary consumer is a 3rd level consumer

Feeding Relationships

• Herbivores eat producers• Carnivores eat herbivores• Omnivores eat producers and consumers• Predators kill for food (consumer); can be a

carnivore or omnivore. • Prey is hunted for food (consumer); can be

herbivore, omnivore or carnivore.

Feeding Relationships• Producers such as plants use the sun to make

energy rich food• Consumers obtain their food by eating other

organisms• Decomposers consume waste and dead

organisms

Energy Flow Through an Ecosystem

Food Chain

• Food Chain - a chain along which energy passes. Energy is transferred form prey to predator

Energy Flows through an Ecosystem through Food Webs

• Food Web – complex network of interconnected food chains and feeding relationships

Energy Pyramid

Shows energy flow. As the amount of available energy decreases, the pyramid gets smaller.

Each layer on a pyramid is called a trophic level

Living Relationships

Symbiosis any close relationship between species, including mutualism, commensalism and parasitism.

Mutualism

A 3-way Mutualism between an ant, a butterfly caterpillar, and an acacia in the American southwest. The caterpillars have nectar organs which the ants drink from, and the acacia tolerates the feeding caterpillars. The ants appear to provide some protection for both plant

Mutualism: Both organisms benefit

CommensalismOne organism benefits and the other is unaffected

Parasitism – one organism benefits and the other is harmed

Succession• Natural, gradual changes in the types of species that live in

an area; can be primary or secondary. – Primary – begins in a place without soil– Secondary – where soil already exists

Primary Succession

Secondary Succession

Pioneer species• A group of organisms, such as

lichens, found in the primary stage of succession and that begin an area's soil-building process

Climax Community

A community that has reached a stable stage of ecological succession

Plants and animals of the community use resources efficiently

Balance is maintained by disturbances such as fire

Biomes

• Large geographic areas with similar climates and ecosystems

TUNDRA

TAIGA

DESERT

DECIDUOUS FOREST

RAIN FOREST

MARINE

Human Impact

Pollution: any substance that contaminates the environment

• Air pollution Cause: smoke, gases, volcanic eruptions, dust,

fires, evaporation of chemicals and burning fuels

Effect: Irritates eyes and lungs, can cause lung diseases

Water Pollution

• Causes: waste water from factories & sewage treatment plants, chemical runoff off from land, and oil spills

• Effects: kills water dwelling organisms, creates shortage of food, increase in algal blooms

Soil Pollution

• Cause: air or water pollutants contaminate ground, improper disposal of trash and chemicals

• Effects: danger to soil dwelling organisms, can pollute ground water

Acid Rain

• Cause: pollutants from burning fossil fuels react with H2O to form strong acids

• Effect: washes nutrients form soil, lowers pH of lakes and pond water, water dwelling organisms die, erodes buildings

Ozone Depletion

• Causes: pollutant gases (CFC’s) leak into the air breaking apart ozone molecules, depleting it

• Effect: depleted ozone allows amount of UV radiation to increase; increase in skin cancers.

Too much ozone at earths surface pollutes the air and can damage lungs and plant tissues

Greenhouse Effect

• Cause: sunlight trapped by atmospheric gases (CO2)

Too much CO2 caused by an increase in burning fossil fuels allows for more sunlight to be trapped, hence Global Warming

Effects: polar ice cap melt, change in rainfall patterns, increase in storms (hurricanes), increase in tropical disease