1.1
What Is an Ecosystem?
Time
45–60 min
Key Ideas
Ecosystems are made up of
living and non-living things.
Groups of living things
interact within ecosystems.
Vocabulary
•
•
•
•
•
•
organisms
micro-organisms
species
population
community
ecosystem
Program Resources
SM 1.1 What Is an
Ecosystem?
BLM 0.0-9 Chapter Key Ideas
Nelson Science Probe 7
Web site
www.science.nelson.com
Page 5
PRESCRIBED LEARNING OUTCOMES
• analyze the roles of organisms as part of interconnected food webs,
populations, communities, and ecosystems
• assess survival needs and interactions between organisms and the
environment
• assess the requirements for sustaining healthy local ecosystems
• create models that help to explain scientific concepts and hypotheses
KNOWLEDGE
• living things interact with each other and their physical environment
• organisms are influenced by environmental forces, and each organism
influences the environment to some extent
• ecosystems are entire systems formed by interactions among the
different living and non-living parts of the environment (e.g., forests,
deserts)
• non-living physical characteristics of an ecosystem include: soil,
landforms, water, sunlight, temperature
ICT OUTCOMES
• access information using a variety of on-line information tools
• apply predetermined search criteria to locate and retrieve information
using information technology tools
• use a variety of information technology tools to create, modify, explore,
and present electronic documents that express ideas or concepts
SCIENCE BACKGROUND
• The Khutzeymateen Valley is home to
one of BC’s most important coastal
populations of grizzly bears. The
Tsimshian nation, which holds
Aboriginal title to the land, supported
the creation of the sanctuary. The
grizzly bear sanctuary has an area of
43 000 hectares (430 km2). This is a
land of dense Sitka spruce rain
forest, fiords, and high rugged
mountains with glaciers. It is
considered old-growth rain forest.
The river estuary wetlands provide
important spawning grounds for
many species of salmon. The grizzly
bears depend on these salmon, as
well as the rich variety of seasonal
plants. The Khutzeymateen Valley is a
dramatic example of a set of
interactions between the living and
non-living elements of the
environment. The heavy rains of the
20
Unit A: Ecosystems
area provide a temperate climate for
lush growth. The salmon runs provide
an important food source for the
bears in the fall. As the bodies of the
salmon decompose and are washed
away by the rain, nutrients are
returned to ecosystems near and far.
• Grizzly bears need varied foraging
grounds and adequate space for
rearing young away from large
males, which may kill cubs or
mothers as they are seen as a threat
to territory. Mother grizzly bears may
range between one or two river
valleys, but the males require a
larger space—something that intact
coastal watersheds can provide.
These ancient forests provide the
grizzlies with denning and bedding
sites and the variety and quantity of
plants and salmon that such a large
animal requires.
NEL
TEACHING NOTES
Related Resources
1 Getting Started
Lynch, Wayne. A is for
Arctic: Natural Wonders
of a Polar World.
Richmond Hill, ON: Firefly
Books, 1996.
• Check for Misconceptions
– Identify: Students may think that an ecosystem consists of only
things they can experience first hand and not non-living things,
such as climate and water.
– Clarify: Explain that an ecosystem is not a specific place but a way
to describe the interactions between living and non-living things.
We may only notice the plants and animals, for example, but
wind, rain, mountains, rivers, and many other non-living things
affect the lives of the organisms. This is what is meant by
“Ecosystems support life.”
– Ask What They Think Now: Ask students, What non-living parts of
your local area or ecosystem affect you?
Mackenzie, Ian. Ancient
Landscapes of British
Columbia. Vancouver, BC:
Lone Pine Publishing,
1995.
Pascoe, Elaine, and Dwight
Khun. The Ecosystem of
a … (series: garden,
grassy field, fallen tree,
milkweed patch, stream,
apple tree). New York:
Powerkids Press, 2003.
• View some photos of the Khutzeymateen Valley from Fortress of the
Grizzlies.
The Nature of Things: The
Salmon Forest (video).
CBC Television, 2001.
• After reading about the meaning of the Tsimshian name
K’tzim-a-deen (Khutzeymateen), inform students that a variety of
translations are offered, including “a deep valley at the end of an
inlet.”
• Elicit from students a list of a few living and non-living things in the
schoolyard. Compare this to the Unit Preview photo, noting the
bears, water, mountains, snow, and vegetation.
Wakeman, Dan, and
Wendy Shymanski.
Fortress of the Grizzlies:
The Khutzeymateen
Grizzly Bear Sanctuary.
Surrey, BC: Heritage
House Publishing
Company, 2003.
2 Guide the Learning
• Have students read The Living Environment subsection. With a
partner, have students take turns explaining how a nested circle
shows how parts fit into a whole. See Reading and Thinking
Strategies: Make Inferences and Reading and Thinking
Strategies: Determine the Meanings of Key Scientific and
Technical Terms for additional strategies to support reading.
• Ask students to think of other words that begin with micro (e.g.,
microscope, micro-machines). Suggest that they look up micro in a
dictionary.
Math Connections
• After listing the non-living parts shown in Figure 3 (e.g., fog, cloud,
moisture, river, mountains, sunlight), ask students to think about
how the non-living parts of the Khutzeymateen Valley are similar to
or different from the non-living parts of their schoolyard.
• For students who need additional support with the reading in this
section, use SM 1.1 What Is an Ecosystem?
3 Consolidate and Extend
• Hand out BLM 0.0-9 Chapter Key Ideas, and have students some add
details and examples.
To help students
understand area measured
in hectares (1 ha 100 m 100 m), have
them measure the length
and width of the
schoolyard and then
estimate or calculate the
area. Remember that
1 km2 100 ha. Also
remember that you need
to multiply by 100, not 10,
to convert units of area as
you move down the scale
from kilo to milli.
• Assign the Check Your Understanding questions.
NEL
Chapter 1
Ecosystems support life.
21
At Home
Have students look near
their homes for common
birds or insects and try to
determine the roles of
these organisms in the
ecosystem. How are
these organisms
connected to other
organisms and to nonliving things? Have
students consider how far
these organisms travel.
CHECK YOUR UNDERSTANDING—SUGGESTED ANSWERS
1. On one side of the page are the living parts, which may include salmon, grizzly
bears, beavers, wolves, otters, trees, shrubs, birds, insects, bacteria, algae, red
elderberry, Sitka spruce, ravens, and coho salmon. On the other side of the
page are the non-living parts, which may include sunlight, rain, snow, soil,
creeks, rivers, mountains, and temperature.
2. The diagram should be similar to Figure 2. Organism names will vary with each
student’s local ecosystem. There should be only one animal in the species circle,
two or more of the same animal in the population circle, and two or more of the
same animals, some different animals, and some plants in the community circle.
3. Possible interactions between two living parts of the environment include birds
eating insects, beavers chewing on trees, and grizzly bears eating salmon.
Possible interactions between two non-living parts of the environment include
sunlight melting snow, a creek flowing into a river, and rain washing away soil.
Reading and Thinking Strategies: Make
Inferences
• Note the Learning Tip on vocabulary. Often, the meaning
of a word can be inferred by the context. Students can
reread, read on, and ask themselves, What would make
sense here? Rereading and reading on will often reveal
explicit definitions of key terms (e.g., This is called …),
particularly in well-written or “considerate” text.
LEARNING TIP
The Living Environment
Important vocabulary words
are highlighted. These are
words you should learn
and use when you answer
questions. These words are
also defined in the glossary
at the back of this book.
The Khutzeymateen Valley has both living and non-living parts.
The living parts, such as plants and animals, are called organisms.
Some of the organisms, such as bacteria and the tiniest algae, are
too small to be seen with your eyes only. Organisms that are too
small to be seen without the help of a microscope are called
LEARNING TIP
It is easier to remember
scientific terms if you
understand the root words.
The Greek word micro
means “small.” Therefore,
micro-organisms are simply
small organisms. Can you
think of other science words
that start with “micro”?
micro-organisms.
Each different type of organism—plant, animal, or microorganism—is known as a species. Grizzly bears are a species
(Figure 2(a)). All the members of one particular species in a given
area, such as the Khutzeymateen Valley, are called a population.
For example, all the grizzly bears in the Khutzeymateen Valley form
a population (Figure 2(b)). When two or more populations of
different species live in the same area, they form a community
(Figure 2(c)). The community in the Khutzeymateen Valley includes
populations of grizzly bears, coho salmon, red elderberry, Sitka
spruce, and ravens.
Reading and Thinking Strategies: Determine
the Meanings of Key Scientific and Technical
Terms
• Note the Learning Tip about micro. Greek and Latin
roots, prefixes, and suffixes often are useful for
understanding scientific and technical terms. Even if
students do not know the meaning of a root, they can
sometimes figure out the meaning of a word by
considering what other words share the same prefix or
suffix.
• Nested circles diagram: Tell students that viewing
illustrations and diagrams, along with the captions,
can support their understanding of key words and
concepts. Read aloud the second paragraph of The
Living Environment. As you read, have students view
the nested circle, focusing on the small inner circle and
moving to the larger outer circles. Ask students how
the text and nested circle graphic work together. Some
students might note that the key words in the
paragraph are the headings for the circles.
22
Unit A: Ecosystems
(c) COMMUNITY
Porcupine
(b) POPULATION
Wolf
Skunk
cabbage
(a) SPECIES
Grizzly
bear
Raven
Grizzly
bear
Grizzly
bear
Grizzly bear
Grizzly
bear
Coho salmon
Sitka spruce
Red elderberry
Figure 2
A nested circle diagram shows how parts fit into a whole. Each species is part of a
population, and each population is part of a community.
6
Unit A
Ecosystems
NEL
NEL
Meeting Individual Needs
ESL
• Students will need support in comprehending “nested circles.” Relate
this idea to something familiar (e.g., use sets and subsets of materials
in a hands-on way and then refer students back to the scientific
meanings).
• You may also need to explain who the “First Nations” peoples of the
province are.
Extra Support
• For students who need additional support with the reading in this
section, use SM 1.1 What Is an Ecosystem?
Extra Challenge
• Research more information on the Khutzeymateen Valley.
www.science.nelson.com
GO
ASSESSMENT FOR LEARNING
What To Look For in Student Work
Suggestions for Teaching Students Who Are Having Difficulty
Evidence that students can
• identify and distinguish between
components of an ecosystem
(e.g., ecosystems are made up of living and
non-living things)
• describe how groups of living things
interact within ecosystems, and give
examples
• create models (e.g., nested circle to show
how organisms are interconnected)
• use technical language correctly
(organisms, micro-organisms, species,
population, community, ecosystem)
• create products that are complete
(e.g., a nested circle)
Provide students with a list (words or sketches) of living things, and ask them to
provide a list of non-living things in the environment that may affect living things.
NEL
Have students choose another animal, and reread the nested circle paragraph and
diagram with students, substituting the chosen species and appropriate other
members of the community.
Chapter 1
Ecosystems support life.
23