540 likes | 734 Vues
Torrey Pines High School Canyon Field Study. An Inquiry Lesson in the Ecology of the Coastal Sage & Chaparral Communities Of San Diego County. PURPOSE of STUDY:.
E N D
Torrey Pines High School Canyon Field Study An Inquiry Lesson in the Ecology of the Coastal Sage & Chaparral Communities Of San Diego County
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. • 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: To collect data to demonstrate plant distribution by microclimate using • Temperature, • Soil Conditions, • Moisture & • Animal or human interference) To document seasonal changes from Fall to Spring
Procedure • Students collect field data on biotic and abiotic factors of the canyon. • And then match the microclimate features to the key index plants
Key Terms Coastal 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 . . . . . . . . • 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 . . . . . . . . • 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 Overview Climax Areas have stable plant Communities: • West Facing Slope(III) • East Facing Slope(I) • Riparian Area (Stream bed-I)
Plant Adaptations . . . . . In order to survive harsh conditions plants must have special features to utilize the available: • moisture • sunlight • nutrients and protect them from animals
Highly Adapted Plants . . . . . . Prickly Pear Cactus • Leaves are ? • Needles for ? • Stem is green for? • Thick & Soft to store?
Key Difference between: Adaptations that help a plant to survive a hot, dry climate by • preventing water loss versus • allowing for water storage
Adaptations . . . . . . . . Too much light or heat can be as damaging as too little & require: • long narrow or tiny leaves • thick hard stems • thick waxy cuticle on leaves to reduce water loss.
Plant Adaptations of the West Facing Slope Top areas . . . . Chamise • hard woody stem • small leaves to prevent water loss. • most highly adapted of the shrubs • for a hot, dry climate.
Mid 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 regions Black Sage • Strong aroma • Moderately large leaves • Turned upward to catch moisture • Silver backing to reflect the hot light
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? 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……. Ceanotheus • What shape is the leaf? • What advantage in a hot, dry climate • What type of stem adaptation
Riparian Plants . . . . . . Riparian =Stream Bed Undergoes succession because of stream erosion • Rushes are round • Sedges have edges • Cattails • Large deep rooted trees
Plant Adaptations of the Riparian 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 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 had living organism but was destroyed & is now recovering.
Plants in the Succession area . . . California Sage • Strong aroma • Very narrow, long leaves • Light gray coloration Reflects hot intense sun light • Green stem Increases photosynthesis area
Plant Adaptations of the East Facing 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.