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http://www.authorstream.com/presentation/farawela-189952-kelp-forest-anatomy-adaptation-type-distrubution-education-ppt-powerpoint/. KELP FOREST. By Feryal Jamal Kherissat.
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http://www.authorstream.com/presentation/farawela-189952-kelp-forest-anatomy-adaptation-type-distrubution-education-ppt-powerpoint/http://www.authorstream.com/presentation/farawela-189952-kelp-forest-anatomy-adaptation-type-distrubution-education-ppt-powerpoint/
KELP FOREST By Feryal Jamal Kherissat
I know few things more surprising than to see this plant growing and flourishing amidst those breakers of the western ocean, which no mass of rock, let it be ever so hard, can long resist. Charles Darwin (1860)
Kelp Anatomy Blade - leaf-like : photosynthesis. Stipe - stem-like structure. Pneumatocyst -Float - air filled bladder @ base of each blade keeps plant at surface for photosynthesis. Holdfast - . Anchor, not root.
Adaptations of Kelp A strong holdfast anchors the kelp to the substrate. A flexible blade moves with the motion of the waves. Growth occurs between the stipe and the blade instead of at the blade tip, where erosion happens. A hollow stipe offers some buoyancy to the kelp structure.
Uh oh…quick biology review Alternation of Generations sporophyte – makes spores gametophyte – makes gametes
Kelp that has been ripped off it's moorings will sometime gather into what is known as drift kelp. This kelp floats and drifts with the currents. This living kelp can, under the right conditions, re-anchor itself in a new area.
DISTRUBUTION Extent of kelp beds depend on: Hard substrate must be available for attachment. Light. Cold temperature (absent in warm temperature and tropical area). Nutrients (Kelps limited by low nutrients).
Ecosystem Architecture 4-Midwater and Surface-canopy kelps include the largest species and often constitutefloating canopies that extend to the ocean surface(Macrocystis, Nereocysitis). 3-Understory-canopy kelps: A) lienear and along the sea floor(Laminaria). B) Extend afew meters above the sea floorand can grow indense aggregations(Eisenia). 2-Bottom-canopy plants (Gelidium, plocamium). 1-The benthic assemblage is composed of otheralgal species, sessile organismsalong the ocean bottom, and encrusting coralline algae . Gelidium Eisenia arborea
Kelp Productivity Among the fastest growing plants in the world in either marine or terrestrial habitats. Maximum elongation rates in the giant kelp Macrocystis pyriferaare on the order of 12 -18 inches per day. Kelp forests are among the most productive communities in the world. Estimates of productivity comparable to tropical rain forests.
Only about 5-10 % of the primary production is consumed by grazers in either terrestrial or kelp forests. In terrestrial forests most of the biomass accumulate on the ground and persists as litter on the forest floor. There is small accumulation of kelp litter because kelps continually sluff organic material which ultimately enters the near shore food web.
"The numbers of living creatures of all Orders whose existence intimately depends on kelp is wonderful… I can only compare these great aquatic forests with the terrestrial ones in the inter tropical regions." Yet if in any country a forest was destroyed, I do not believe nearly so many species of animals would perish as would here from the destruction of kelp.“ Charles Darwin (1860) The Voyage of the Beagle
Kelp As Nurseries • Blades break waves/currents (rock lobsters, abalone, snapper and wrasse). • Shade allows growth of delicate algae provide food for a range of grazing animals ( snails). • Hiding spaces between plants offers protection for non-moving animals (sponges , sea squirts). • Blades and stipes = anchoring point for small algae whichin turn can be eaten by grazing animals.
Kelp Vs. Herbivores Urchins • Snails
Kelp Forest Food Webs Sea Otters are at the top of the kelp forest food chain No sea otters—sea urchins take the top spot
Mechanical forces (storm) Ripped by storms LAND TUMBLE BEACH continue food for to live herbivores/ detritivores
Marine pollution and water quality Die from Sewage Fertilizers Suspended sediment (dredging/ erosion phytoplankton)
This caused by dense planktonblooms, lasting for over six weeks, with visibilityless than 4m. The next year, a similar disaster happened, and it took six years before the kelp forest had a closed canopy again. Murky water causes untimely kelp death, the ones lower down being starved of light first. This kelp forest is symptomatic of habitat degradation.
Invasion species The arrival of species from other countries: grow faster out compete for space on rocky reefs. Underlie pinnatifida wakame
Kelp Harvesting And Fisheries • food for other species • food for humans • toothpatse/antacid