TEXTBOOK
AND
WORKBOOK
ANSWERS
–
CHAPTER
3.2
TEXTBOOK…
SECTION
3.2
ASSESSMENT,
p.
137
Check
Your
Understanding
Answers
Checking
Concepts
1.
Human
activities
affect
wetland
ecosystems
when
wetlands
are
transformed
into
parking
lots,
subdivisions,
garbage
dumps,
agricultural
land,
and
shopping
malls.
In
addition,
pollution
from
agriculture
and
industry
and
the
introductions
of
invasive
species
have
also
degraded
these
ecosystems.
2.
A
sustainable
ecosystem
provides
economic
opportunities
while
maintaining
biodiversity
and
ecosystem
health.
3.
Habitat
fragmentation
harms
ecosystems
as
plant
pollination,
seed
dispersal,
wildlife
movement,
and
plant
and
animal
reproduction
are
affected.
4.
Deforestation
results
in
soil
degradation
because
the
loss
of
plant
life
causes
water
and
wind
erosion,
which
removes
topsoil
from
bare
land.
5.
The
loss
of
topsoil
affects
an
ecosystem
because
plants
require
adequate
amounts
of
topsoil
to
grow
and
anchor
in,
and
when
topsoil
erodes,
the
nutrients
are
lost
with
the
topsoil.
6.
(a)
Water
contamination
is
the
introduction
of
chemicals,
toxins,
waste,
or
microorganisms
into
the
environment
in
concentrations
that
are
harmful
to
living
things.
(b)
Mining
causes
water
contamination
when
chemicals,
such
as
cyanide
used
in
gold
and
silver
mining,
enter
streams
and
rivers.
7.
Two
ways
plants
can
be
used
in
mine
reclamation
are
to
absorb
contaminants
through
their
root
systems
and
to
stabilize
the
soil
to
prevent
the
contamination
from
leaching
into
the
water.
8.
Overexploitation
can
lead
to
extinction
when
a
population
becomes
so
reduced
that
the
genetic
diversity
is
lost.
With
the
loss
of
genetic
diversity,
populations
are
less
resistant
to
disease
and
less
able
to
adapt
to
changes
in
their
environment.
9.
Controlled
burning
practices
positively
affect
ecosystems
because
this
practice
recycles
nutrients
and
increases
growth
of
plants,
which
attracts
wildlife.
It
also
reduces
forest
litter
and
opens
the
forest
canopy
for
plants
that
require
more
sunlight.
If
forest
litter
is
reduced,
forest
fires
will
be
less
intense.
Understanding
Key
Ideas
10.
One
sustainable
practice
that
can
reduce
the
negative
effects
of
urban
expansion
is
adopting
3.2
TXT
+
WKBK
answers.docx
Page
1
of
5
development
plans
that
incorporate
waste
treatment,
storm
water
collection,
and
mixed
residential
and
business
building
use.
11.
(a)
The
collapse
of
the
cod
fishery
was
due
to
overexploitation.
(b)
Populations
in
ecosystems
are
affected
by
overexploitation
as
numbers
and
genetic
diversity
are
reduced.
12.
(a)
The
sustainable
practice
shown
in
the
photograph
is
using
plants
for
land
reclamation
after
a
mine
closure.
(b)
In
10
years,
the
area
may
be
restored
to
a
forest
and
attract
a
variety
of
wildlife.
13.
Overexploitation
can
affect
many
interactions
in
a
food
web
as
the
numbers
of
predators
of
the
organism
will
decrease
and
the
number
of
prey
of
the
overexploited
organism
will
increase.
This
can
further
affect
other
organisms
connected
in
the
food
web.
14.
Traditional
ecological
knowledge
can
affect
the
biodiversity
of
an
ecosystem
as
seen
in
spring
burning
of
prairie
grasslands
by
Cree.
Controlled
burning
renewed
grassland
ecosystems,
recycling
nutrients
and
increasing
plant
growth,
which
attracted
small
mammals
to
the
area.
Carnivores,
such
as
coyotes,
were
attracted
by
the
increase
in
prey
populations.
WORKBOOK…
Section
3.2
How
Humans
Influence
Ecosystems
Comprehension
Sustainability
Page
46
1.
Sustainability
is
the
ability
of
an
ecosystem
to
sustain
ecological
processes
and
maintain
biodiversity
over
time.
It
also
means
that
humans
use
natural
resources
in
a
way
that
maintains
ecosystem
health
now
and
for
future
generations.
2.
Habitat
loss
refers
to
the
destruction
of
habitats
while
habitat
fragmentation
is
the
division
of
habitats
into
smaller,
isolated
fragments.
3.
Deforestation
is
the
practice
in
which
forests
are
logged
or
cleared
for
human
use
and
never
reforested.
This
practice
results
in
a
reduction
of
the
number
of
plants
and
animals
living
in
an
ecosystem.
Erosion
occurs
since
few
plants
are
left
to
hold
the
soil
in
place.
As
a
result
of
the
erosion,
nutrients
are
lost
so
plants
are
not
able
to
grow.
4.
Aeration,
or
breaking
up
compacted
soil,
reduces
run‐off
by
improving
the
movement
of
air
and
water
through
soil.
5.
Examples
of
contamination
due
to
mining
could
include
introduction
of
chemicals,
toxins,
wastes,
or
micro‐organisms
into
the
environment.
6.
Overexploitation
can
result
in
extinction
of
a
species
and
a
loss
of
genetic
diversity.
In
turn,
the
populations
are
less
resistant
to
disease
and
less
able
to
adapt
to
changes
in
their
environment.
3.2
TXT
+
WKBK
answers.docx
Page
2
of
5
7.
Traditional
ecological
knowledge
takes
the
form
of
stories,
songs,
cultural
beliefs,
rituals,
community
laws,
and
practices
related
to
agriculture,
forests,
and
ocean
resources.
It
reflects
the
knowledge
about
local
climate
and
resources,
biotic
and
abiotic
characteristics,
and
animal
and
plant
cycles.
Applying
Knowledge
Effects
of
human
activities
on
ecosystems
Page
47
Analyzing
Information
HUMAN
ACTIVITY
Deforestation
EFFECTS
ON
ECOSYSTEM
•
reduction
in
number
of
plants
and
animals
living
in
an
ecosystem
•
erosion
due
to
lack
of
plant
roots
holding
soil
in
place
•
removal
of
nutrients
from
topsoil
•
wind
erosion
•
soil
compaction
•
hindering
growth
of
plants
•
addition
of
excess
nitrogen
and
pollutants
due
to
increased
run‐off
•
contamination
of
ground
water
and
surface
water
through
introduction
of
chemicals,
toxins,
wastes,
or
micro‐organisms
•
contaminants
affect
local
plant
and
animals
•
reduction
in
population
of
particular
fish
•
loss
of
genetic
diversity
in
food
web
•
species
less
resistant
to
disease
and
changes
in
environment
agricultural
practices,
such
as
leaving
fields
bare
during
nonplanting
seasons
exploitation
of
mining
resources
overexploitation
of
natural
resources,
such
as
fish
3.2
TXT
+
WKBK
answers.docx
Page
3
of
5
Sustainability
Page
48
Assessment
How
humans
influence
ecosystems
Page
49
1.
B
2.
D
3.
G
4.
E
5.
F
6.
A
7.
C
8.
C
9.
D
10.
A
11.
B
3.2
TXT
+
WKBK
answers.docx
Page
4
of
5
EXAMPLE
OF
LAND
USE
3.2
TXT
+
WKBK
answers.docx
Page
5
of
5