190 likes | 488 Views
Kelp Forests Dominated by brown algae Found in shallow open coastal settings where water temperature usually < 20 o C Bottom depth typically <20 m Light readily available Highly productive, diverse ecosystems Productivity related to fast kelp growth rates. Fig. 16-7. Pacific Fig. 16-8.
E N D
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
Pacific Fig. 16-8 Atlantic Fig. 16-9
Kelp Forests • Factors Affecting Kelp Forests • Intensity and frequency of winter storms • Presence/Absence of urchin predators (sea otters/lobsters) • 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
Kelp Forests • 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
Plants • Bryophytes • Non-vascular plants • Dominant gametophyte • Marchantiophyta (liverworts) • Anthocerotophyta (hornworts) • Bryophyta (mosses)
Plants • Pteridophytes • Vascular plants • Dominant sporophyte • Lycopodiophyta (club mosses) • Pteridophyta (ferns, whisk ferns, horsetails) sierrapotomac.org stevie8126.blogspot.com malag.aes.oregonstate.edu
Plants • Seed Plants • Vascular plants • Dominant sporophyte • Cycadophyta (sago palms) • Ginkgophyta (ginkgo) • Pinophyta (conifers) • Gnetophyta (gnetales) • Anthophyta/Magnoliophyta (flowering plants)**
cycads southafrica.net ginkgo ucmp.berkeley.edu Welwitschia biolib.cz conifers frogsonice.com
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
parenchyma collenchyma sclerenchyma
Flowering Plants (Anthophyta) • Monocots vs. dicots holganix.com