© Lisa Michalek

EcologyThe study of the interactions between

organisms and the living and nonliving components of their environment.

An Ecologist is a scientist who studies Ecology.

Ecology InvolvesCollecting information about organisms and their environment.

Looking for patterns.Seeking to explain these patterns.

Environmental OrganizationIn Ecology, organisms and the

environment are studied at various ecological levels.

Each level includes different factors.PopulationCommunityEcosystemBiosphere

Environmental OrganizationPopulation

A population includes all the members of a species found in a given area.

The dandelion species in your lawn is an example of a population.

Environmental OrganizationCommunity

A community includes all the populations in a given area.

Your lawn has populations of dandelions, grasses, earthworms, and other living things.

These populations together make up a lawn community.

Environmental OrganizationEcosystem

A community (all the living things) and the physical environment (air, water, soil) interacting and functioning together make up an ecosystem.

Examples of ecosystems include your lawn, a balanced aquarium, ponds, vacant lots, woodlots, salt marshes, and forests.

Environmental OrganizationBiosphere

The biosphere is the portion of the earth in which life exists.

It is very large and includes many complex ecosystems.

Stable Ecosystem Requirements An ecosystem can support itself and is

stable when the following requirements are met.

1. There must be a constant supply of energy. The sun is the primary source

of energy for life on Earth.

2. There must be living organisms that can incorporate the energy into organic compounds.

3. There must be a recycling of materials between organisms and the environment.

Ecosystem ComponentsAbiotic Factors

The nonliving parts of the environment.They directly affect the ability of organisms to live and reproduce.

These factors vary from one place to another.

Abiotic factors may act as limiting factors. Limiting factors determine the numbers and kinds of organisms that can inhabit an ecosystem.

Abiotic FactorsLightClimate (Temperature)Slope of the landType of SoilSoil chemistry (Minerals)Surface and ground waterAir

Ecosystem ComponentsBiotic Factors

All the living things that directly or indirectly affect the ecosystem.

Biotic factors interact with other living organisms and with the physical environment.

Biotic FactorsProducers

Any plant that manufactures food by photosynthesis.Green plants are producers.

ConsumersConsumers eat producers and/or other animals.

All animals are consumers.Decomposers

Decomposers break down dead organisms and make their materials available to other living things. Bacteria and fungi are examples of decomposers.

Ecosystem CharacteristicsAbiotic components combine to define the

environmental characteristics of the ecosystem.

Biotic components interact with each other to determine the success of life in the ecosystem.

Biotic components interact with Abiotic components to determine the overall characteristics of the ecosystem.

HabitatThe place in the ecosystem where an

organism lives.An organism’s habitat is determined by

abiotic and biotic factors. The factors an organism needs to survive

determine where it lives.Example: An earthworm’s habitat is moist

soil.

NicheAn organism’s role in the ecosystem.Includes feeding habits, where it lives in the

ecosystem, reproductive behavior, and contribution to its surroundings.Example: In a pond, a snail scrapes algae

from the leaves and stems of plants.

BiomeA geographical area described by its

climate, plants, and animals.The temperature and moisture in a

biome determines which plants will grow there.

Biomes may be terrestrial (land) or aquatic (water) biomes.

Land (terrestrial) BiomesPlant and Animal groups are determined by

the major climate zones of the earth.They are sometimes modified by local land

and water conditions.The presence or absence of water is a major

limiting factor.Climate conditions and communities are

affected bylatitude (distance north or south of the equator)

andaltitude (distance above or below sea level).

Terrestrial (Land) BiomesTundra (polar)

Taiga (coniferous forest)

Temperate Deciduous Forest

Tropical Rain Forest

Grassland (savanna)

Desert

Tundra(Polar)

Permanently frozen subsoil.Animals: Caribou, snowy owl, arctic foxesPlants: Lichens, mosses, grasses

Tundra Video

Taiga(Coniferous Forest)

Long, severe winters; summers with thawing of subsoil.

Animals: Moose, black bearPlants: Coniferous Trees (produce their seeds

in cones) spruce, fir, hemlock, cedar, and pine trees

Taiga Video

Temperate Deciduous

Forest

Moderate precipitation; cold winters, warm summers.

Animals: Gray squirrel, fox, deer, raccoonsPlants: Trees that shed leaves

(deciduous trees), oak, beech, maple, elm trees

Deciduous Forest Video

Tropical Rain Forest

Heavy rainfall; constant warmth.Animals: Snake, monkey, leopard, parrotsPlants: Many species of broad-leaved plants,

bamboo, fernsTropical Rain Forest Video

Grassland(Savanna)

Rainfall and temperature vary; strong prevailing winds.

Animals: Antelope, prairie dog, bison, hawksPlants: Grasses, cereal grains

Grassland (Savanna) Video

Desert

Little rainfall; extreme daily temperature changes.

Animals: Lizard, kangaroo rat, coyotes, camelsPlants: Drought-resistant shrubs and plants,

cactus

Desert Video

Water (aquatic) BiomesInclude marine (saltwater) and freshwater

biomes.Make up the largest ecosystem on earth.More than 70% of the earth’s surface is

covered by water, and more organisms live in water than live on land.

Water biomes are typically more stable than land biomes.

The temperature varies less because of the ability of water to absorb and hold heat.

Factors Affecting Water BiomesAmounts of available oxygen and

carbon dioxide.Temperature and light.Amounts of dissolved minerals

and suspended particles.

Aquatic (water) BiomesMarine

(saltwater)

Freshwater

Marine(saltwater)

Oceans, Intertidal ZonesHold large quantities of solar heatHelp to stabilize the earth’s atmosphereContain a constant supply of nutrients and dissolved saltsMuch of the photosynthesis on earth is carried out by

algae near the surface of the oceans and coastal waters.Light penetrates through water to a depth of 30 meters.

Photosynthesis does not occur at greater depths.

Freshwater

Less than 3% of the Earth’s water is fresh water.Ponds, Swamps, Lakes, Streams, and Rivers

will vary by:SizeSpeed of currentTemperatureConcentration of dissolved gasses and suspended

particlesRate of change