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11 Cards in this Set
- Front
- Back
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Give three important characteristics of the sclerophyll leaf.
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-Composed of tough lignin=long lasting
-lignin composed of cheap raw materials (C, O, H) -small leaf size ALL done to reduce initial energy investment |
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How does the sclerophyll leaf conserve water?
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-drab color=reflects more light
-leaves hang vertically=less exposure -thick cuticle=reduced transpiration -stomata down in pits -thick leaves=wilt resistant |
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How does a eucalypt conserve energy?
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-small initial investment in leaves
-drop lower shaded out branches -mutualistic relationship with termites hollow out dead wood which gets recycled back to the soil |
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How do eucalypts encourage fire?
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Some eucalypt's bark peels off and falls to the forest floor to increase the fuel load. Eucalypt leaves have a highly flammable oil to encourage fire.
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What is mycorrhizal fungi?
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A symbiotic organism that grows in concert with a plant's root system to increase the surface area available to that tree for nutrient uptake. Fungi in return get sugars created by the plant.
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How do eucalypts reproduce?
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Large arrays of stamens (no flower petals) attract pollinators (often vertebrates). After fertilization, seeds form encased in a woody gum nut which will not open to reveal the seed until after a fire.
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Name two plants integral in the heathland.
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-Peas (Fabaceae) and heaths (epacridaceae)
-tiny ericoid leaves=small investment |
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What are the three types of heathland and how do they differ?
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Dry= deep porous soil drains easily
Wet= seasonally waterlogged & stagnant Montane= exposed mtn. tops, extreme climate exposure on skeletal soils |
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How have plants adapted to survive in the low nutrient soils of heathlands (and elsewhere)?
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Nitrogen fixation = root symbiosis w/ bacteria that turn atmospheric nitrogen into a plant-usable form
Mychorhizal roots = root symbiosis w/ fungi by increasing surface area for phosphorous uptake Cluster roots = dense fine branching root mats at the surface |
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Why are heathlands so diverse?
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Harsh conditions may prevent competitive exclusion...allows species to develop subtle differences in how to exploit the scarce resources.
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How have eucalypts and other australian vegetation fared abroad?
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-Melaleuca (like eucalypt but wetland specialist) taken over the Florida Everglades altering the ecosystem.
-Eucalypt planted abroad = poor wildlife habitat, dry out the soil Basically, they take over! |
