chaparral - chaparral around the globe. chaparral from spanish word for el chaparro, shrubby...

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Chaparral -

Chaparral around the

globe

Chaparral

• from Spanish word for el chaparro, shrubby evergreen oaks in Spain.

• Gave name to chaps, leg protectors to riding horse back through this tough vegetation type.

• Covers about 8 % of the state.• Found in drier sites (south slopes) on

western slope of Sierras, along Coastal Ranges

• Found On dry or nutrient poor soils

• Common on serpentine as well.

• Associated with Mediterranean climates.

• Often evergreen shrubs with small tough (sclerophyllous) leaves.

• Often with resinous or waxy coverings.

• Very dry in summer, leading to fires.

Resinous & waxy coverings

• Odor of flowers attract pollinators

• Odor in foliage indicates compounds that deter herbivory.

• waxy or oily covering may also protect from desiccation

• Makes easy for it to combust

Root systems

• Two-tiered root systems, absorb water longer into the season.– Shallow roots to get rains, fast spring growth– Deep roots for water late in the season

• Nitrogen fixing bacteria in roots common.– help after nitrogen loss in fires.

• Mycorrhizae fungi associated with roots, that help obtain nutrients and water. – Most of the mushrooms in the forest, e.g.

Chanterelles.

Growth cycle

• Sierra Chaparral flushes out later that coastal chaparral, but grows for longer time.

• Lower photosynthetic rate than drought deciduous, but can grow all season.

• Above ground growth in wetter months, root growth mostly in summer.

Fire Cycle• Community most likely to burn in many areas.• Many homes now built in these areas.• Early succession after fire, nutrient limited, mostly

annuals and forbs (herbs) wildflowers.• Many species are sprouters-

– Burl survives fire, seeds out new shoots afterwards

• new growth may be very high in protein 14%, deer and other animals rely on this growth.

• some closed cone pines - need fire to release seeds.• Fire follower annual- seeds in soil seed bank

germinate and predominate first few years after fire• Shrub canopy closes in about 6 years

Fire poppies in burn area

Madrons sprouts from burl

Ceanothus seedlings sprout after fire

1 month post fire

Schmidts, M.J., D.A. Sims, J.A. Gamon California State University, Los Angeles, CA

http://vcsars.calstatela.edu/eas_00/miriam/miriam_esa_00.html

First spring 3 years post fire

20 and 40 years post fire

Old fires• Before fires limited by suppression:• Had a patch-work mosaic of previously burned

areas, smaller areas available to burn each time– now with suppression large areas burn very hot. – Now they can kill burrowing animals and much more

severe erosion in the fall rains.

• Old records some long-lasting (months) slow-moving smouldering fires, similar to the Sierras.

• Large oaks have a thick non-resinous bark, fire proof, to former low fires.

Frequent fires lead to a mosaic of different stand ages in Southern California

chaparral vegetation

Mosaic of ages burns

Soils

• High erosion rates. – Often on steep slopes, sandy soils.

• Accumulate hydrophobic waxes and oils (resins) they prevent them from taking up moisture.

• Hot fires moves these chemicals down deeper and forms and non-wettable layer below. Wet upper layer washes off.

Two of the several different types of Chaparral in

California

• Maritime Chaparral– Along the north coast- Bodega Bay– Similar to Briones

• Warm Chaparral– Similar to Mt. Diablo, and Sierra foothills on the

way to Yosemite

Maritime Chaparral • also known as Coastal Scrub• Similar to plants in Briones, Bodega bay• have bendable, or soft flexible leaves.• most are odoriferous and drought tolerant

shrubs.• low growing, knee high• influenced by summer fog, cool winters, little

frost.• shallow root systems that can quickly absorb

fog drip.• dry, 10 inches or less of precipitation per year.

• South Slopes have small leaves and drought deciduous– Ca Sagebrush, Artemisia an indicator species.

• finely divide leaves, flush out new growth with winter rains.

– Bush monkey flowers - seasonal leaf dimorphism• flush with many leaves in winter.• Only very small terminal leaves remain alive in dry

months.

• North Slopes- larger shrubs, small trees with large leaves and deep root systems. – Toyon. Poison oak, Coyote bush.

• Northern Coastal Scrub - as by BodegaBay– Coyote bush, Salal, Yerba Santa and Yellow Bush

Lupine. – Very near coast and mixed with coastal prairies.

Maritime ( soft) chaparral

North Coast chaparral

Warm Chaparral

Warm chaparral • on lower slopes of mountains, • below snow line; is frost tolerant, but not

snow tolerant.• Most are evergreen with waxy or resinous

coverings, not drought deciduous.• Strong north - South slope effect, large/small

leaves• Sclerophyllous (very tough, rigid leaves).

– Long lived and well protected leaves.– Stiff leaves, with non digestible fibers, protect from

herbivores– reduce water loss

Chamise (Adnostema)• Most common in southern ranges and Southern

ca.• Very small, needle like drought adapted leaves.• Well adapted to sprouting after fires.• Has both fire and non fire seeds. • Can reestablish by seeds after a hot fire that

kills the burl.• At high temperatures, chamise emits flammable

gasses that ignite, and spread the fire.

Chamise

Chamisal

Ceanothus spp.• Common genus in California, many different

species.• Recognizable usually by three main veins on

underside of leaf • Early successional species.• They do not sprout, need to seed in after

fires.• Warm soils stimulate seeds dormant in seed

bank to grow.• Many have nitrogen-fixing bacteria that help

replenish the scorched soils. • Import deer food – e.g. Buck brush

Ceanothus- California Lilac

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