Torrey Pines High School Torrey Pines High School Canyon Field StudyCanyon Field Study

An Inquiry Lesson in the Ecology of the

Coastal Sage &

ChaparralCommunities

Of San Diego County

PURPOSE of STUDY:PURPOSE of STUDY:

• San Diego County has a unique range of ecological communities that begin at the coast line and progress westward across the coastal plain, into foothills, mountains, and a desert region.

• The rain shadow effect created by this geographical transect provides a unique set of micro climates that define these communities.

Purpose cont.Purpose cont.

• East and West Facing canyons along the coastal belt show similar plant transitions and microclimates

• Students analyze these slopes and then compare and contrast their findings to the larger geographic distributions

Class Objectives:Class Objectives:To collect data to demonstrate plantdistribution by microclimate using• Temperature, • Soil Conditions, • Moisture &• Animal or human interference)To document seasonal changes from Fall toSpring

ProcedureProcedure

• Students collect field data on biotic and abiotic factors of the canyon.

• And then match the microclimate features to the key index plants

Key TermsKey TermsCoastal Sage and

Chaparral-

• a scrub land biome • of dense shrubs • found along the coast• characterized by

mild, rainy winters• and long, hot, dry

summers

Key Terms . . . . . . . .Key Terms . . . . . . . .

• Humus-The product of decaying matter from plants, animals, and decomposers

• Index Plant-A main plant found in abundance in a particular community

Key Terms . . . . . . . .Key Terms . . . . . . . .

• Transect Line-A line of vegetation selected for charting plants.

• Microclimate-A climate of an area with important factors such as precipitation and temperature.

Canyon OverviewCanyon Overview

Climax Areas havestable plantCommunities:• West Facing

Slope(III)• East Facing

Slope(I)• Riparian Area

(Stream bed-I)

Plant AdaptationsPlant Adaptations . . . . . . . . . .

In order to survive harshconditions plants musthave special features toutilize the available:• moisture• sunlight• nutrients and protect them from

animals

Highly Adapted Plants . . . . . .Highly Adapted Plants . . . . . .

Prickly Pear Cactus

• Leaves are ?• Needles for ?• Stem is green for?• Thick & Soft to

store?

Key Difference between:Key Difference between:

Adaptations that help a plant to survive a hot, dry climate by

• preventing water lossversus

• allowing for water storage

Adaptations . . . . . . . .Adaptations . . . . . . . .

Too much light or heatcan be as damaging astoo little & require:• long narrow or tiny leaves • thick hard stems• thick waxy cuticle on leavesto reduce water loss.

Plant Adaptations of the West Plant Adaptations of the West Facing Slope Facing Slope TopTop areas . . . . areas . . . .

Chamise• hard woody stem • small leaves to prevent

water loss. • most highly adapted of

the shrubs • for a hot, dry climate.

Mid slope regionsMid slope regions . . . . . . . . . . . .

Lemonade Berry• Thick waxy cuticle on

leaves • Thick stems to prevent

water loss• BUT broad leaf is not as

able to survive extreme conditions, so it is a mid slope belt

Plants in the lower slope regionsPlants in the lower slope regions

Black Sage• Strong aroma• Moderately large

leaves• Turned upward to

catch moisture• Silver backing to

reflect the hot light

Mid Slope Plants cont. . .Mid Slope Plants cont. . . . . . . . . . .

Baccharis or Chaparral Broom• Small light green

leaves• Green top stems• Hard woody bottom

stems• Stiff & bushy…

broom!

Questions to ponder?Questions to ponder?

Flattop Buckwheat• How does it get its

name?• Why so many leaves?• What function does

the swirl & clustering of these leaves provide?

Mid Slope Plants…….Mid Slope Plants…….Ceanotheus• What shape is the

leaf?• What advantage

in a hot, dry climate

• What type of stem adaptation

Riparian PlantsRiparian Plants . . . . . . . . . . . .

Riparian =Stream BedUndergoes successionbecause of stream erosion • Rushes are round• Sedges have edges• Cattails• Large deep rooted

trees

Plant Adaptations of the Plant Adaptations of the RiparianRiparian

Laurel Sumac-• long, broad leaves are

NOT well adapted• curled leaves • help gather water & • reduce the amount of

surface area exposed to the hot sun

• thick woody stem • to prevent water loss

The Succession Study Area IVThe Succession Study Area IV

Succession Area• South slope adjacent to the football field• Cleared & filled for the stadium • Grasses, small shrubs, and opportunistic

species first colonize these areas.This secondary succession area once hadliving organism but was destroyed & is now

recovering.

Plants in the Succession area . . . Plants in the Succession area . . .

California Sage• Strong aroma• Very narrow, long

leaves• Light gray coloration

Reflects hot intense sun light

• Green stemIncreases photosynthesis area

Plant Adaptations of the East Plant Adaptations of the East Facing SlopeFacing Slope

Scrub Oak- • relatively large tree-like structure• dark, cupped oval leaves• for gathering water• with prickles for protection This plant is an index plant of the foothills community at higher, cooler, elevations.

East Facing Slope…..East Facing Slope…..Mazanita- • large tree• long broad leaves• large surface, but are

curled downward• red, woody stem

prevents water loss.

References References

• Http://bio.lmu.edu/socal_nat_hist/nathist.htm

• Ancinec, G. et al. 1979. Natural History of Southern California, A laboratory guide, Peek Publications, Palo Alto, CA.