Post on 06-Jan-2016
description
transcript
I. Kelp Forests
• Dominated by brown algae• Found in shallow open coastal settings
where water temperature usually <20 oC• Bottom depth typically <20 m
• Light readily available
• Highly productive, diverse ecosystems• Productivity related to fast kelp growth rates
Fig. 16-7
Atlantic Fig. 16-9Pacific Fig. 16-8
I. Kelp Forests
Atlantic Pacific
Grazers Urchins Urchins, Abalones, Limpets
Suspension Feeders
Mussels Mussels
Predators Maine Lobsters
Sea Otters
I. Kelp Forests
A. Factors Affecting Kelp Forests1. Intensity and frequency of winter storms
2. Presence/Absence of urchin predators (sea otters/lobsters)
3. Abundance and behavior of herbivores• Winter storms can rip kelps from their holdfasts• After severe storms, portions of sea floor may be stripped
of kelp• Urchins deprived of preferred foods (mature kelp or drift
algae) may increase mobility and eat newly recruited kelps• Grazing may prevent kelps from re-growing
• Leads to establishment of more resistant coralline algae• Leads to urchin barrens
vanaqua.org
Fig. 16-14
hopkins.stanford.edu
I. Kelp Forests
B. Kelp Forest Ecology• Sea otters/Lobsters important top-down
regulators of community structure• Prey on important grazers like urchins (Pac/Atl) and
abalones (Pac)
• Urchins, abalones, other herbivores graze on attached seaweeds, drift kelp
• Urchin populations can have a major impact on community composition
Fig. 16-11
Fig. 16-15
II. Plants
A. Bryophytes• Non-vascular plants• Dominant gametophyte
1. Marchantiophyta (liverworts)
2. Anthocerotophyta (hornworts)
3. Bryophyta (mosses)
bio1151.nicerweb.com
II. Plants
B. Pteridophytes• Vascular plants• Dominant sporophyte
1. Lycopodiophyta (club mosses)
2. Pteridophyta (ferns, whisk ferns, horsetails)
sierrapotomac.org
malag.aes.oregonstate.edustevie8126.blogspot.com
II. Plants
C. Seed Plants• Vascular plants• Dominant sporophyte
1. Cycadophyta (sago palms)
2. Ginkgophyta (ginkgo)
3. Pinophyta (conifers)
4. Gnetophyta (gnetales)
5. Anthophyta/Magnoliophyta (flowering plants)**
cycadssouthafrica.net
ginkgoucmp.berkeley.edu
conifersfrogsonice.com
Welwitschiabiolib.cz
II. Flowering Plants (Anthophyta)
• True roots, stems, leaves• Roots
• Mechanical anchors• Absorb water, minerals• Often with root hairs (increase surface area for absorption)• May store carbohydrates
• Stems• Elevate and separate leaves• Elevate reproductive structures• Nodes, internodes
• Leaves• Main photosynthetic organ• Blade, petiole, veins
• Specialized vascular tissues that transport water, minerals, nutrients
• Xylem – Water• Phloem – Minerals, nutrients
thomson.fosterscience.com
parenchyma
collenchyma
sclerenchyma
micro.magnet.fsu.edu
II. Flowering Plants (Anthophyta)
• Monocots vs. dicots
holganix.com