Ecosystems and Energy

Honors Biology

Ms. Leyda

2012-2013

What is Ecology ?

The study of how

organisms interact with one another

and their non-living

environment

So Then What is an Ecosystem ?

Looking at the chart to the right..

BiosphereBiosphere

Ecosystems

Communities

Populations

Organisms

Our BIOSPHERE is the part of the Earth where

the organisms exist

And an ECOSYSTEM is that area where the living

and non-living things interact.

So Then What is an Ecosystem ?

Looking at the chart to the right..

BiosphereBiosphere

Ecosystems

Communities

Populations

Organisms

A COMMUNITY is different populations that live together in a defined

area

And an POPULATION is a group of individuals of

the same species that live in the same area

Parts of an EcosystemAn Ecosystem is made of BIOTIC and ABIOTIC parts

BIOTIC components are the living parts of the ecosystem

Examples are:

• Plants

• Animals

• Fungi

• Bacteria

Parts of an EcosystemAn Ecosystem is made of BIOTIC and ABIOTIC Components

ABIOTIC components are the NON-living parts of the ecosystem

Examples are:

• Water

• Air

• Temperature

• Sunlight

Energy for the Ecosystems

Every ecosystem on Earth gets its energy from the same source:

The SUN !!!

Looking closely at Ecosystems

All Ecosystems are made of four components linked by the flow of energy.

These components are:

• Primary Producers• Consumers

• Decomposers• Abiotic Environment

Looking closely at Ecosystems

External energy source

PRIMARYPRODUCERS

CONSUMERS DECOMPOSERS

ABIOTIC ENVIRONMENT

Primary Producers

Producers make their own food, from abiotic factors, such as sunlight or

heat from chemical reactions.

Primary Producers

Producers are also known as Autotrophs

Some examples are:

• Plants

• Algae

• Bacteria

Consumers

Consumers are organisms that get their energy by eating other organisms

Consumers

Consumers are also known as Heterotrophs

Consumers can be:

• Herbivores

• Carnivores

• Omnivores

• Detritivores (Decomposers)

Consumers

Herbivores eat only plants.

Herbivore Examples:

• Large Mammals (Such as cattle & deer)

• Some Insects

Consumers

Carnivores eat other animals

Carnivore Examples:

• Lions, Tigers

• Wolves

• Sharks

• Snakes

Consumers

Omnivores eat both plants and animals

Omnivore Examples:

• Humans

• Bears

• Mice

• Pigs

Consumers

Detritivores eat dead plants and animals (also called decomposers)

Detritivore Examples:

• Worms

• Beetles

• Bacteria

• Fungi

Food Chain

A Food Chain tells us what eats what in an ecosystem. It shows the series of

organisms through which food energy is passed.

Food Chain

The arrow means “is eaten by”

In this case the dragonfly is eaten

by the frog.

Food Chain

Remember…

ALL food chains begin with a Producer

( Also known as an Autotroph)

Food Web

In an ecosystem, there are many producers and

consumers.

Instead of a food chain, we can

use a food web.

Food Web

A food web shows the complex

relationship formed by the overlapping

and interconnecting food chains.

Humans

Blue whaleSperm whale

Crabeater seal

Killerwhale Elephant

seal

Leopardseal

Adéliepenguins Petrel

Fish

Squid

Carnivorous plankton

Krill

Phytoplankton

Herbivorouszooplankton

Emperorpenguin

Food Web

To better understand a food web, we can look at an energy pyramid.

An energy pyramid is a way to graph how much energy is passed up the food

chain from one organism to the next.

Energy Pyramid

Let’s look at the energy pyramid closer.

Each layer of the pyramid is called a Trophic Level.

A Trophic Level is a level of

nourishment in a food chain.

Energy Pyramid

Let’s look at the energy pyramid closer.

The pyramid first shows us the Producers.

Remember… Producers get their energy from the sun.

Producers are the first and largest Trophic

Level. Producers

Energy Pyramid

Let’s look at the energy pyramid closer.

Second, we see the Primary Consumers

The Primary Consumers get their

energy from eating the Producers.

Primary Consumers can be either Herbivores or Omnivores. Primary Consumers

Energy Pyramid

Let’s look at the energy pyramid closer.

Third, we see the Secondary Consumers

The Secondary Consumers get their

energy from eating the Primary Consumers

Secondary Consumers are Carnivores or

Omnivores Secondary Consumers

Energy Pyramid

Let’s look at the energy pyramid closer.

Fourth, we see the Tertiary Consumers

The Tertiary Consumers get their

energy from eating the Secondary Consumers

Tertiary Consumers are Carnivores or

Omnivores Tertiary Consumers

Energy Pyramid

Let’s look at the energy pyramid closer.

Some energy pyramids can have a fifth Trophic

Level.

Usually this fifth level is humans.

Energy Pyramid

Let’s look at the energy pyramid closer.

Biomass is the total amount of

living tissue within each trophic level.

Energy Pyramid

Let’s look at the energy pyramid closer.

Only 10% of the energy from the

prior trophic level is passed on.

This is because energy is lost to the environment

as heat

Energy Pyramid

If an energy pyramid consists of plants that contain 500,000 calories of food energy, how many calories of energy would be available to consumers at each of the next three trophic

levels?

Trophic level

Primary producers

Tertiary consumers

Secondary consumers

Primary consumers

Energy Pyramid

Primary Consumers:

Trophic level

Primary producers

Tertiary consumers

Secondary consumers

Primary consumers

Secondary Consumers:

Tertiary Consumers:

500,000 cal x .1 = 50,000 calories

50,000 cal x .1 = 5,000 calories

5,000 cal x .1 = 500 calories

Food WebWhat does these energy numbers tell us??

Trophic level

Primary producers

Tertiary consumers

Secondary consumers

Primary consumers

1) There are very few Tertiary consumers, because it takes a HUGE amount of food energy to support them.

2) For a large population to exist, it needs to feed from the LOWEST trophic level possible, because there is more food energy available.

Other Pyramid typesBesides the energy pyramid, we can also have pyramids of:

1)Numbers2)Biomass

Pyramid of NumbersA pyramid of numbers reflects the number of species at each

trophic level.

For example: if we look at a forest, there may be few rose bushes, but many insects that feed on

the tree, with a pyramid like the one below.

Pyramid of BiomassA pyramid of biomass reflects the total amount of living tissue

at each trophic level.

For example: Looking at the same forest, the biomass is great.