Movement of Energy Through an Ecosystem: Producers and

Consumers• PRODUCERS (autotrophs) –plants,

bacteria and algae are the first to capture the energy from the SUN.

Some autotrophs can produce energy in the absence of sunlight, these organisms (many are bacteria) use chemicals to produce energy in a process known as CHEMOSYNTHESIS

• CONSUMERS (heterotrophs)- All other organisms in an ecosystem that consume plants or other organisms to obtain energy are called

Types of consumers1. Herbivores – obtain energy from

eating plants

2. Carnivores- eat other animals

3. Omnivores – eat both

4. Detrivores – feed on plant remains and other dead matter. Ex. Mites, earthworms, snails and crabs

5. Decomposers – break down organic matter. Ex. Bacteria and Fungi

The Movement of Energy Through Ecosystems:Food Chains

• The path of energy through the trophic levels of an ecosystem is called a FOOD CHAIN.

• Shows simple straight paths of energy.

Ex. Grassland Food chain

Trophic Levels

The Movement of Energy Through Ecosystems:

Trophic Levels in a Food Chain• 1st level always starts with a producer.

(Plant)• 2nd level consists of herbivores. Called

primary consumers. • 3rd level consists of carnivores or

omnivores Called secondary consumers. 4th level tertiary or third order consumers-

top carnivores in an ecosystem.

Food Chains

Food Chains

The Movement of Energy Through Ecosystems:Food Webs

• In most ecosystems energy does not follow simple straight paths like those shown in a food chain.

• FOOD WEB- used to show many food chains together, makes more sense

Food Web

Ecological Pyramids

• Diagram that shows relative amounts of energy or matter contained within each trophic level in food chain or web.

• 3 types:Energy PyramidBiomass PyramidPyramid of Numbers

Energy Pyramid

• At each trophic level energy is lost as heat or the organisms biological processes (i.e. respiration, movement, etc.)

• Only about 10% of the energy available within a trophic level is transferred to organisms at the next trophic level.

• Loss of energy limits the amount of trophic levels an ecosystem can support.

• Called the Rule of 10• Anyone remember the law of the

conservation of energy you learned in IPC?

The Movement of Energy Through Ecosystems:

Loss of Energy in a Food Chain This loss of energy is known as the 10% Rule

or Octet rule.Ex. A plant receives 9,000kcal of

energy from the sun. How much energy does the tertiary consumer receive?

9000 900 90 9

What shapes an Ecosystem?

Abiotic and Biotic Factors• ABIOTIC FACTORS – physical,

NONLIVING parts of a habitat.Ex. Soil, water, weather,

temperature.■ BIOTIC FACTORS – all LIVING parts

in a habitat. Together these factors determine the

survival and growth of an organism and the productivity of an ecosystem.

Community Interactions

1. Competition – occurs when different species try to use the same ecological resources at the same place and same time.

Direct competition will result in a winner and loser – the loser failing to survive.

2. Predation – one organism captures and feeds on another organism.

PREDATOR – does the killingPREY – organism that is killed

3. Symbiosis – relationship in which 2 species live closely together – literally means “living together”

3 types 1. Mutualism 2. Commensalism3. Parasitism

1. Mutualism

• Relationship where BOTH participating species BENEFIT. They cannot live without each other.

Ex. Honeypot ants and aphids

1. Mutualism

2. Commensalism

• Only one organism benefits, the other organism neither benefits or is harmed.

3. Parasitism• One organism benefits by harming

another organism, WITHOUT KILLING THEIR HOST! Normally smaller than their host.

Ex. Dogs with fleas

Sea lamprey and fish