ecology notes

ECOLOGY

What is Ecology?

Ecology is the study of the relationships among

organisms and their environment.

Ecologists study environments at different levels of organization.

• Ecology is the study of the interactions among living things, and between living things and their surroundings.

Organism

Organism

• An organism is an individual living thing, such as an alligator.

Organism

Organism

Population

Population

• A population is a group of

the same species that lives in

one area.

Organism

Organism

Population

Population

Community

Community

• A community is a group of

different species that live

together in one area.

Organism

Organism

Population

Population

Community

Community

Ecosystem

Ecosystem

• An ecosystem includes all of

the organisms as well as the

climate, soil, water, rocks and

other nonliving things in a given

area.

Organism

Organism

Population

Population

Community

Community

Ecosystem

Ecosystem

Biome

• A biome is a major regional or

global community of organisms

characterized by the climate

conditions and plant communities

that thrive there.

• A biosphere is the global ecosystem

– The sum of all the planet’s ecosystems and biomes

Biotic and Abiotic Factors

What factors both living and non living will affect my life?

3 minutes ToTHINK

Factors affecting mouse

• Predators

• Food

• Shelter

• Temperature

• Weather

• Competitors

• Pathogens

• Parasites

• Clean Water

Would the same factors affect this flower?

Factors Affecting Plant

• Predators

• Food

• Shelter

• Temperature

• Weather

• Competitors

• Pollinators

• Soil

• Nutrients

• Wind

• Aspect

• Daylight

Keywords for today

• Biotic

• Abiotic

At the end of today’s lesson you will be able to

• Define biotic and abiotic

• Give examples of each type of factor

Classify the factors in the picture as either biotic factors or abiotic factors

List the Biotic and Abiotic Factors in the Image

Decide whether the following items are Abiotic, Biotic, or can be

argued to be both, place in the Venn diagram.

Abiotic Biotic

Biotic or Abiotic or Both?

Fish Chair Water Train Atom Plastic Insects Wood Sea Shell

Dirt Dog Worm Burger Wheat T.V. Broccoli Pine Tree Energy

Flower Dead animal Wooden Table Cotton Shirt Sunlight Ice Hydrogen Strawberries Wind

Abiotic Factors

• Factors that relate to the weather

• Factors that relate to the soil

What climatic factors could we measure?

• Light Intensity

• Humidity

• Wind speed

• Temperature

• Aspect

• Slope

What soil factors could we measure?

• Soil pH

• Amount of water in soil

• Soil Temperature

• Soil Air

• Soil Texture

List the Biotic and Abiotic Factors in the Image

The Deer Population

A field study was conducted to observe a deer population in a given region over time.The deer were counted at different intervals over a period of 40 years. During this period of time both ranching and hunting increased in the study region.

A summary of the data is presented in the table.

Questions on Deer Population

• During which 10 year period did the greatest increase in the deer population occur?

• State one possible action that could have been used to help maintain a more stable population of deer in the area.

• Identify an abiotic limiting factor for the deer populations.

• Identify a biotic limiting factor for the deer populations.

• List two problems an overpopulation of deer can cause in the environment.

Abiotic Factors

Biotic Factors

Decide if Factor is Biotic or Abiotic

Write A if Abiotic_______ Mouse _______ Rocks _______ Water _______ Fish _______ Paper _______ Glass _______ Aluminum _______ Wooden Ruler _______ Sand_______ Clouds

Write B if Biotic_______ Corpse _______ Snail _______ Vegetation_______ Bread Mold _______ Trees_______ Soil_______ Plastic _______ Pipe _______ Air_______ Wind

Habitat• All of the biotic and abiotic factors in the area

where an organism lives

• Factors

– Grass

– Trees

– Water

Niche• All of the physical, chemical, and biological

factors a species needs to survive, stay healthy, and reproduce in an ecosystem.

Madagascar

South America

Animated Biology

• Survive within a Niche

Lion niche in African Savannah

Find 4 factors that help the lion survive.

An antelope may use the tall grasses of the African plains as a food resource, a lion may use the same grasses as camouflage for hunting. A lion uses the antelope as a food resource and hunts primarily during low-light times like dawn or dusk. In order to avoid the intense heat of the savannah, lions often spend afternoons in the shade.

What are some of the abiotic and biotic

factors of your habitat?

ABIOTIC:

air, temperature, buildings, roads, water

BIOTIC:

Pets, plants, people

COMMUNITY INTERACTIONS

Competition

• Two organisms fight for the same limited resource.

– Intraspecific competition

• Within a species

– Interspecific competition

• Two different species compete for the same resource

Predation

• Predator/Prey – one organism eats the other

• Predator – does the eating

• Prey – gets eaten

Symbiosis

• A close relationship between two or more species where at least one benefits

Kinds of Symbiosis

1. Mutualism – Both species benefit from the relationship

2. Commensalism – one species benefits and one is not affected

3. Parasitism – one species benefits and the other is harmed

Examples of Interactions

• National Geographic

Terminology Review

• Autotroph

– Make their own food

• A.K.A. Producer

• Heterotroph

– Get energy from eating other living resources

• A.K.A. Consumer

Terminology Review: Types of Consumers

• Herbivore

– Eats only plants

• Carnivore

– Eats only animals (meat)

• Omnivore

– Eats both plants and animals

• Detritivores/Decomposers

– Eats dead organic matter

Trophic Levels:Levels within the food chain where an organism obtains its energy

Trophic Levels• Primary Producer (autotrophs)

– Make their own food from sunlight and/or chemical energy from deep sea vents

– The base of every food chain

Trophic Levels

• Primary Consumer

–Eat producers

• Herbivores

Trophic Levels

• Secondary Consumers

–Eat Primary Consumers

• Carnivores and Omnivores

Trophic Levels

• Detrivores/Decomposers

– Eat dead organisms

Trophic Levels

• Tertiary Consumers

–Eat secondary consumers

• Quaternary Consumers

–Eat tertiary consumers

• The top of the food chain has animals with little or no natural enemies

Energy Flow

• 10% Rule

–Only about 10% of the energy in any level of a food pyramid is available to the next level.

Example: When you eat an apple, only about 10% of the energy in the apple will end up being used by you.

Energy Pyramid

Energy Pyramid

Energy Pyramid Vocabulary

• Population size decreases as level increases

• Biomass – total dry weight of living matter at a level

Practice Questions

If we were trapped on a fertile grass island, about the size of a soccer field,

should we plant food crops or graze animals? Why?

• Island can produce 10,000 different edible plants.

• Island can provide food to graze one small cow, and two goats. They can produce a few glasses of milk.

A: We should plant crops!

• There is more available energy in producing vegetables than animals.

• We may get 10,000 plants

• The field may support one small cow which will just give a small amount of milk, even less energy if we use our one animal for BBQ.

Study the drawing to the right.

Infer the effect on the number of the pyramid’s organisms if an infection lowered the number of primary consumers to 100,000

Hypothetical Problem

AlgaeWater fleasMinnowFishHumans

A human weighs about 100 kg. According to the above food chain, how many humans can 100 million kilograms of algae support?