Intertidal Ecology  Rocky Shores  Sandy Shores: sandy beaches  Muddy Shores: mud flat.

Download Intertidal Ecology  Rocky Shores  Sandy Shores: sandy beaches  Muddy Shores: mud flat.

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<ul><li> Slide 1 </li> <li> Slide 2 </li> <li> Intertidal Ecology Rocky Shores Sandy Shores: sandy beaches Muddy Shores: mud flat </li> <li> Slide 3 </li> <li> Divisions of Ocean environment </li> <li> Slide 4 </li> <li> Where? Who? What are they doing there? </li> <li> Slide 5 </li> <li> Why did these students have to stand in water to do the work? </li> <li> Slide 6 </li> <li> Mixed, semidiurnal, and diurnal tide curves. </li> <li> Slide 7 </li> <li> Highest tide Lowest tide Intertidal Flat Subtidal zone The intertidal zone is the zone between the highest and lowest tides </li> <li> Slide 8 </li> <li> Flood and ebb tides Water-air alternative exposure Rhythmic Rich diversity and density within a small area Characteristics of the intertidal zones </li> <li> Slide 9 </li> <li> Length of maximum submergence (hours) </li> <li> Slide 10 </li> <li> Rocky Shore Ecology Zonation Factors affecting zonation Physical Environmental Conditions Biological Interactions </li> <li> Slide 11 </li> <li> Typical Rocky intertidal zonation patterns(Pacific) Zonation: Predictable distinctive distribution pattern of marine organisms through intertidal zone </li> <li> Slide 12 </li> <li> Typical Rocky intertidal zonation patterns(Atlantic) </li> <li> Slide 13 </li> <li> Zonation of major species on rocky shores. The figure is a general scheme of common animals and algae found in eastern North America. Details will differ for specific locations. </li> <li> Slide 14 </li> <li> Classification of zones in all habitat type (Ricketts et al., 1985) Zone 1: uppermost horizon: Highest reach of spray and storm waves -- the mean of all high tides: the splash, spray, supralittoral, or Littorina zone Zone 2: high intertidal: Mean high water -- a bit below mean sea level: the home of barnacles and other animals tolerating more air than water Zone 3 : Middle intertidal: about mean higher low water -- mean low water Zone 4: Low intertidal: normally uncovered by minus tides only. This zone can be examined during only a few hours in each month </li> <li> Slide 15 </li> <li> Factors modifying zonation of Rocky shore Abiotic Wave action and tidal range Desiccation Heat stress Salinity reduced feeding time DO and gas exchange Biotic Larval settlement Intra- and interspecific competition Predation and grazing Physiological tolerance and adaptation behavioral pattern, mobility </li> <li> Slide 16 </li> <li> Exposure-shelter diagram for Hong Kong shores. The range of the six litterine species are superimposed. 1. Nodilittorina pyramidalis; 2. Nodilitorina millegrana; Peasiella sp.; 4. Littorina brevicula; 5. Littorina scabra; 6. Littorina melanostoma. </li> <li> Slide 17 </li> <li> Physical conditions of rocky intertidal areas Tides-Periodical change the organisms' living environments Temperature-desiccation (could be fatal), particular in tropic region Wave action--exerts the most influence on organisms and communities </li> <li> Slide 18 </li> <li> Physical conditions of rocky intertidal areas (cont) Wave action (cont) mechanical effect--smash and tear away objects; acts to extend the limits of the intertidal zone by throwing water higher on the shore (splashing allows the marine organisms to live higher in exposed wave- swept areas than in sheltered areas within the same tidal range change the topography of intertidal area by move substratum around mix atmospheric gases into the water--increasing the oxygen content </li> <li> Slide 19 </li> <li> Salinity-the intertidal may be exposed at low tide and subsequently flooded by heavy rains or runoff from heavy rains --- either would sense severe problems Substratum topography - grain size would change pH and nutrients (not very important) Physical Conditions of Rocky intertidal areas (cont) </li> <li> Slide 20 </li> <li> General distribution patterns Random distribution: distribution of organisms can be explained by random chance Even distribution: organisms occur in an even manner Patchiness: Organisms occur in isolated groups within a larger contiguous suitable habitat </li> <li> Slide 21 </li> <li> Adaptation Adaptation to desiccation (water loss) Move to moist place or under the moist cover (crabs &amp; snails) Tolerate high % water loss (Fucus, Porphyra, Enteromorpha, up to 60-90%) Reduce water loss by close shells (snails, barnacles, limpets home scar) Build shield to cover up (sea anemone or sea urchin covered with shell fragments) </li> <li> Slide 22 </li> <li> Changes in the extent of vertical zonation with change in exposure to wave action. </li> <li> Slide 23 </li> <li> Diagrammatic representation of the adaptations to water loss in intertidal organisms. </li> <li> Slide 24 </li> <li> Many snails of the genus Littorina live high in the intertidal zone. When exposed, the snail protects itself from desiccation by pulling back into the shell and covering the opening with the operculum. First it secretes a mucous thread that attaches the shell to the rock. </li> <li> Slide 25 </li> <li> Adaptation Adaptation to high temperature (heat) Temperature shock can affect, metabolic and biochemical processes, such as enzyme function and oxygen demands. retard cellular activities, such as ciliary motion. inhibit behavioural activities, such as feeding &amp; protection against predators. inhibit reproductive behaviour, such as egg laying and copulation. </li> <li> Slide 26 </li> <li> Adaptation Adaptation to high temperature (heat) Reduce heat gain from the environment. Have a relatively large body size (less surface area relative to volume and less area for gaining heat, taking longer to heat up). (Littorina spp larger at high tidal zone) Reduce the area of body tissue in contact with the sbustrate (difficult to achieve swept off by waves) Increase heat loss from the body Elaborated shell ridges &amp; sculptures acting as heat radiators (snails) Light-colored body (gain and lost heat slowly) Water evaporation (holding extra water in mantle cavity of barnacles, limpets exceeds the amount the animal needs to survive desiccation) </li> <li> Slide 27 </li> <li> Differences in heat absorption between smooth, dark shells and sculptured, light shells. </li> <li> Slide 28 </li> <li> Adaptation Adaptation to wave action (smashing and tearing effects) Limitation of size and shape (relatively small, squat bodies with streamlined shapes to minimize the exposure to the lift and drag of wave forces) Flexible and bending (seaweed) Firm attachment by holdfast (algae), cemented shell Temprary attachments by byssal threads (which can be borken and remade) Thick shells, no delicate sculpturing Large foot to clamps to the substrata Seek shelters (crabs) </li> <li> Slide 29 </li> <li> The distribution of barnacles from shelter to exposure (from Tain Tam to Cape DAguilar). 1. Balanus tintinnabulum volcano; 2. Tetraclita squamosa; 3. Pollicipes mitella; 4. Balanus variegatus variegatus; 5. Balanus amphitrite amphitrite; 6. Balanus albicostatus albicostatus; 7. Euraphia withersi. A detail of the numbers and fusion of the valves of the principal genera are also given. </li> <li> Slide 30 </li> <li> Algal formation of exposed vs. sheltered coasts </li> <li> Slide 31 </li> <li> Adaptation Respiration (gills highly susceptible to desiccation in air) Enclose in a protective cavity to prevent them from drying (molluscs) Reduction of the gill and formation of a vascularized mantle cavity Mantel tissue act as lung for aerial respiration (barnacles) Close up (operculum) or clamp down (chitons and Limpets) to reduce gaseous exchange Remain quiescent druing low tide to conserve oxygen and water </li> <li> Slide 32 </li> <li> Adaptation Salinity (flood by fresh water or expose to extremely high salinity) Osmoconformers: organisms without mechanisms to control the salt content of their body fluids using same adaptation as to prevent desiccation. Osmoregulators: organisms with physiological mechanisms to control the salt content of their internal fluids </li> <li> Slide 33 </li> <li> Causes of patchiness in algae on rocky shores. (A) Sweeping action of algal fronds. (B) Irregular spatial and temporal distribution of grazers. (C) Fluctuations in recruitment. (D) Refuge from grazing provided by pits and cracks in rock. (E) Escape of spoelings from grazers. </li> <li> Slide 34 </li> <li> Biological factors controlling rocky intertidal zonation Competition (barnacles as examples) Predation (starfish, mussels, and barnacles) Grazing (sea urchin on seaweed) Larval settlement Interaction among the controlling factors community ecology </li> <li> Slide 35 </li> <li> Biological factors controlling rocky intertidal zonation Competition (barnacles as examples) Predation (starfish, mussels, and barnacles) Grazing (sea urchin on seaweed) Larval settlement Interaction among the controlling factors community ecology </li> <li> Slide 36 </li> <li> Intertidal zonation as a result of the interaction of physical and biological factors.The larvae of two barnacles, Chthamalus stellatus and Balanus balanoides, settle out over a broad area. Physical factors, mainly desiccation, then act to limit survival of B. balanoides above mean high water of neap tides. Competition between B. balanoides and C. stellatus in the zone between mean tide and mean high water of neap tides then eliminates C. stellatus. </li> <li> Slide 37 </li> <li> Effect of desiccation and competition on two species of intertidal barnacles </li> <li> Slide 38 </li> <li> Controlling factors High tidal zone Chthamalus stelatus settled here Semibalanus balanoides have no sufficient tolerance to drying and high temperatures. Mid tidal zone Chthamalus stelatus settled here but was overgrew, uplifted or crushed by Semibalanus balanoides </li> <li> Slide 39 </li> <li> The main groups of algal grazers at different intertidal zones in temperate and tropical systems. </li> <li> Slide 40 </li> <li> Effect of sea urchin removal on kelp growth on the Isle of Man, Great Britain. </li> <li> Slide 41 </li> <li> Interaction of predation and physical factors in establishing the zonation of the dominant intertidal organisms on the rocky shores </li> <li> Slide 42 </li> <li> Interactions among mussels (Mytilus), barnacles, and their predators on the northwester Pacific coast of North America, which allow barnacles to persist in the intertidal zone. </li> <li> Slide 43 </li> <li> Succession in a northwest Pacific coast intertidal mussel bed in the absence of Pisaster. </li> <li> Slide 44 </li> <li> Flow chart of Rocky intertidal Succession </li> <li> Slide 45 </li> <li> Rocky intertidal food web. </li> <li> Slide 46 </li> <li> Sandy and Muddy Shores 1. Shape up of beaches Sediment size Wave action Slope 2. Surroundings Exposed vs protected Oceanic vs semi-enclosed waters, estuaries or wetlands Seasonal vs non-seasonal 3. Sediment movement Swash and backwash Longshore transport SandyMuddy Larger Stronger Slopy Exposed Oceanic Seasonal Applicable </li> <li> Slide 47 </li> <li> 4. Physical conditions of intertidal flats Grain size Interstial space Pore water Water retention 5. Biogeochemical conditons Oxygen Organic matter RPD 6. Organisms SandyMuddy Larger Greater Fluctuation Weaker ShallowerAnoxic Rich Strong, Shallower Diversity Abundance Production High Large High </li> <li> Slide 48 </li> <li> Water moves on shore at an angle returns straight down the beach So sand downcast in a zigzag path Net Transport of sand Longshore current Longshore transport Longshore Transport Processes Path of sand on beach Shoreline Surf zone </li> <li> Slide 49 </li> <li> Swash: water running up a beach after a wave breaks; this action carries particles with it, which may cause accretion of the beach if the particles remain there Backwash: water flowing back down the beach; this action removes particles from the beach, depending on the particle size Slope: the slope of a beach is the result of the interaction between particle size, wave action, and the relative importance of swash and backwash water. Dissipative beach: occurs where wave action is strong but the wave energy is dissipated in a broad, flat surf zone located some distance from the beach surface (gentle swash, fine sediments, gentle slope Reflective beach: occurs where wave action impinges directly on the beach face and the sediment is coarse (no offshore surf zone, wave produce large swashes up the beach face, steep slop). Backwash and swash collide to deposit sediment and wave energy is directed against the face of the shore and reflected off the surface. Some terms </li> <li> Slide 50 </li> <li> Classification of particle sizes </li> <li> Slide 51 </li> <li> The udden- wentworth particle size classification </li> <li> Slide 52 </li> <li> Slide 53 </li> <li> High tide Low tide Water drains out at low tide High tide Low tide Water retained at low tide Particle size Slope Water retention Particle retention Surface to volume absorption Oxygen Organisms Comparison of the physical conditions found in fine-grained and coarse-grained beaches </li> <li> Slide 54 </li> <li> Environmental characteristics of coarse- and fine-particle beaches </li> <li> Slide 55 </li> <li> The process of alongshore drift </li> <li> Slide 56 </li> <li> Surface stability of particulate shores. Surf causes a suspension of the particles. Waves 1m in height disturb the sediments to a depth of 8 cm. Burrowing in this shifting substrate is difficult. </li> <li> Slide 57 </li> <li> Organisms Types of organisms Flora: plant community Fauna: animal community Epifauna: animals dwelling on the surface of sediment Infauna: animals dwelling below the surface of sediment Microfauna: organisms &lt; 0.1 mm Meiofauna: 0.062 mm - 0.5 mm Macrofauna: &gt; 1 mm </li> <li> Slide 74 </li> <li> Organisms Adaptations Burrowing: to construct by tunneling, or digging, e.g. polychaetes, Tubes: siphon tube, large clams-long siphons to prevent clogging respiration pathway, heavy shell to prevent storms Mobile: move quickly with passing wave, commonly employed by many annelid worms, small clams, and crustaceans. Eg. Sand crabs populate the world beaches, have a short body with limbs highly modified to dig quickly into wet sand. As soon as they are freed from the substrate by a passing wave, they reburrow quickly again before wave motion carries them offshore </li> <li> Slide 75 </li> <li> Food sources Phytoplankton Benthic algae (microalgae-diatoms, macroalgae-red algae, green algae, seagrass) Detritus: small debris of organic matter, from dead organisms Bacteria </li> <li> Slide 76 </li> <li> Feeding Types: Deposit feeders (by deposit feeding): Surface deposit feeders Burrowing deposit feeders Suspension feeders: filter feeders Detritus feeders Scavengers </li> <li> Slide 77 </li> <li> Mudflat Ecology Organisms Adaptations of organisms Types of organisms Feeding Biology </li> <li> Slide 78 </li> <li> Physical factors of muddy beach Muddy shores are restricted to intertidal areas compl...</li></ul>