What does Ecology study?

EcologyEco- oikos - houseIs the study of the interactions among living things and their environment

Levels of Organization• Organism

– Individual living thing• Population

– All the members of the same species in a given area and time

• Community– All the different populations in

the same area at a given time• Ecosystem

– Includes all the living and nonliving factors in a given area

• Biome– Major region community of

organisms characterized by climatic conditions

• Biosphere– The area where living things can

inhabit

An Ecosystem consists of all the living and non-living factors in a given area

Biotic – Living things or

influences from living things

– Competition– Predation

Abiotic– Non-living factors– Weather, humidity,

sunlight, soil, sound, wind…

Use the diagram above to list the factorsBiotic Abiotic

   

   

   

   

   

What is meant by Biodiversity?Biodiversity• The variety of living

things in an ecosystem.• Highest in the rainforest

• Only covers 7% of earth but contains 50% of the biodiversity of species

• Lowest in the tundra or desert

• Depends on factors such as moisture and

temperature.

Is there an species that has an unusually large effect on its ecosystem?

Keystone species hold together an ecosystem

Beavers with their damsConfers in the tundraShould the keystone

species disappear, there would be major changes to the ecosystem

An ecological food pyramid shows the flow of energy in an ecosystem

ConsumerHeterotroph

AutotrophProducer

Most of the energy is found in the producers

Herbivores come next

Least amount of energy in the carnivores and the top level consumers

A food chain is a sequence of feeding that links species by their feeding relationships.

Producer 1st Consumer 2nd Consumer 3rd level consumer Top consumer Plant Herbivore Carnivores …………………………………………….

Producer 1st Consumer 2nd Top consumer Top consumer Plant Herbivore Carnivore Carnivore

Put these organisms into a food web

And in the end, where does all the energy end up?

The decomposers, which are fungus & bacteria, recycle the nutrients in dead matter and return them to the ecosystem

Is a food chain a realistic representation of food relationships in an ecosystem?

What else may eat the grass, the grasshopper, the frog, or the snake?

Food webs Shows the complex network of feeding relationships and the flow of energy within and sometimes, beyond the ecosystem

Examine the food web shown below. Identify the various trophic levels

Producers

Primary Consumers

Secondary Consumers

Tertiary Consumers

Top Consumers

Just as the energy needs to be cycled through the living organisms in an ecosystem, so do the non-living factors such

as O2, CO2, Water and Nitrogen

Biogeochemical cycles move particular chemicals or elements through the biotic and abiotic parts of the ecosystem.

• Water Cycle– Cycles water through precipitation, condensation, runoff

and evaporation• Carbon Cycle– Cycles CO2 and O2 through photosynthesis and respiration

• Nitrogen Cycle– Cycles atmospheric nitrogen through bacteria in the soil to

the plants and then to the animals

Water Cycle

Carbon Cycle

Nitrogen Cycle

What happens to all the energy as it flows through each trophic level? Is all of it transferred?

Observe the energy pyramid shown below.

Which trophic level will contain the most collect energy ___________________

Which will have the least amount of collective energy stored in it?

_____________________

How is energy lost at each trophic level? Think of a word you learned at the start of the school year when we discussed the

characteristics of all living things

METABOLISM!!!– Organisms use the energy to keep it going– Moving– Digesting– Absorbing– Reproducing

Most of the energy is lost as heat!!!!

Only 10% of the energy is actually transferred to the next trophic level

If only 10% is transferred and 90% is lost, which organisms on this food pyramid would one be better off eating?

Most of the energy is in the producers.

Think of how much food the lion must eat to keep up its metabolism!!!