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How do abiotic factors vary in different parts of the ocean?
- • Abiotic
- – Physical
- • Light
- • Temperature
- • 3D structure
- • Bottom composition
- – Chemistry
- • Salinity
- • Nutrients
- • Pollutants
- • Affect primary production, behavior, body shape,coloration, health etc.
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How do biotic factors vary in different parts of the ocean?
- • Biotic
- – Other individuals (same species)
- – Other species
- • Influence behavior
- – Competition
- – Predation
- – Cooperation
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How are living things distributed in the ocean in terms of biodiversity, productivity and species composition?
- 1. Estuary
- 2. Intertidal
- 3. Shelf
- 4. Pelagic
- 5. Epipelagic
- 6. Benthic
- 7. Deep sea
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What factors can limit population growth?
- 1. Abiotic environment
- – ex. Light/nutrient limitation
- 2. Overcrowding
- 3.Competition
- – resources
- – space
- 4.↓ Food,↑Waste
- 5. Best competitors survive and reproduce (natural selection)
- → Evolution and speciation
- 6. Carrying Capacity
- • Maximum number of individuals environment can support
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How can carrying capacity can be shifted?
- – Increase food supply
- – Decrease mortality
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importance of biodiversity
- – Lives of all species on planet interconnected
- • Energy flow, food, oxygen
- • Nutrient cycles, waste processing
- • Climate
- – Higher productivity and efficiency
- – Higher resilience
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Factors influencing productivity
- 1. Resources
- – Light
- – Nutrients
- 2. Energy flow
- – Sun
- – Primary producers
- – Consumers
- 3. Nutrient flow
- – Decomposers
- – Producers
- – Consumers
- – Decomposers
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How do various organisms facilitate or exclude other individuals/species?
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Carbon cyle
- Photosynthesis
- – Organic molecules
- • Carbohydrates
- • Lipids
- • Proteins
- • Nucleic acids
- Respiration
- • Continually cycled through system
- – Producers
- – Consumers
- – Decomposers
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Nitrogen cycle
- 1. Nitrogen Fixation
- • Organic molecules
- – Proteins
- – Nucleic acids
- 2. Excretion
- • Continually recycled
- – bacteria
- 3. Denitrification
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Phosporous cycle
- 1. Primary Production
- • Organic molecules
- – Nucleic acids
- 2. Sedimentation
- • Recycling
- – geological
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Marine Productivity: Coastal areas
- • Most productive
- • Most diverse
- • Most human impact
- – Highest populations
- – Development
- – Use of habitat
- – Waste disposal, pollution
- – Exploitation of resources
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Simple food chain: Antarctic waters
- • Nekton (baleen whale)
- ^
- • Zooplankton (krill)
- ^
- • Phytoplankton (diatoms)
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How does energy move up a food chain?
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What advantages or disadvantages are there to living at various levels of a food web?
- 1. Advantages of consuming at lower levels
- • Larger food source
- • Higher energy
- • Less accumulation of toxins (bioaccumulation ofpollutants)
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How can changes in populations of one trophic level affect organisms at other levels?
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What strategies for predation and avoiding predation are used in different situations?
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Intraspecific (Competition)
• Between individuals of the same species
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Interspecific (Competition)
• Between individuals of different species
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Competitive exclusion:
– One competitor outcompetes and excludes another
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Factors influencing the competition
- 1. Physical changes can favor less competitive species/individuals allowing both to survive
- – Seasonal changes
- – Disturbances
- • Storms
- • Predation
- 2. Avoiding competition
- • Resource partitioning
- – Spatially
- – Temporally
- – Specialization
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Advantages of specialization
- – Reduced competition
- – Increase efficiency
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Disadvantages of specialization
– Limited by resource
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Advantages of generalization
– More options
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Disadvantages of generalization
– Potentially less efficient
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Increased predation can....
- • Increased predation can wipe out prey populations,leading to decline in predator populations (limited resource)
- • Prey populations must be larger than predator populations
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Indirect effects of Predation
- • Effects on species other than the prey species
- – Ex. Kelp forests/urchin barrens
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Predation strategies
- • Speed, power
- • Surprise
- • Disable
- • Lure
- • Trap
- • Overtake
- • Drill into
- • Partial vs. total consumption
- – Chiton vs. parrotfish
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Avoiding predators Strategies
- • Speed
- • Schooling
- • Camouflage
- • Burying/burrowing
- • Spines/shells
- • Toxins/poisons
- • Regeneration
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Coevolution
- –evolve in response to other species
- – “Arms race”
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Where does historical climate data come from?
- • Ice cores
- • Tree rings
- • Corals
- • Marine sediments
- • Historical records
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Consequences of Climate change
- • Polar and glacial ice melt
- • Sea level rise
- • Accelerated warming(decreased light reflection)
- • Changing weather patterns
- • Altered productivity
- • Coral bleaching
- • Shifts in species distributions and reproduction
- • Freshwater shortages (↓snow melt)
- • Ocean acidification (CO2 dissolved in seawater)
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Ocean acidification
- • Dissolves calcium carbonate CaCO3
- • organisms with shells, skeletons from protists to corals,Molluscs to vertebrates
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Consequences of Nitrogen cycle alteration
- Consequences
- – Smog (irritation, lung/heart disease, cancer)
- – Damage to ozone layer
- – Acid rain
- – ↓ terrestrial primary production andbiodiversity
- – Eutrophication ↑ marine algal growth →dead zones and harmful algal blooms
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Highly variable environments; most accessible to study
- 1. Intertidal
- – Temperature
- – Salinity
- – Air exposure
- – Hard or soft substrate
- 2. Estuaries
- – FW + seawater– Runoff
- • Sediments
- • Nutrients
- • Pollution
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Rocky intertidal: Formation
- – Geological activity
- • Active margins
- – Glaciation
- • scraping
- – Wave action
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Rocky Intertidal: Challenges
- 1. Dessication
- -Water loss while exposed
- 2. Temperature Variation
- -Air more variable than water
- 3. Salinity Variation
- - Extremes do cause mortality
- 4. Wave Action
- -uneven distribution of wave energy
- - Exposed: wave shock
- -Sheltered: sedimentation
- 5. Tide Restricted feeding
- - higher in the intertidal= less time submerged=less filter feeding
- 6. Space
- - grow on each other
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Rocky intertidal: Strategies/Adaptations
- 1. Mobile
- • follow water
- • Hide in crevices/shade
- • Cluster together
- • Seal air out
- 2. Sessile
- • Seal air out
- • With stand water loss
- • Settle in close groups
- 3. Physiological
- • wider tolerance
- 4. Morphological
- • Ridges: ↑ SA
- • Coloration
- – White: reflect light
- – Dark: absorb light
- 5. Behavioral
- • Seal up or move when salinity changes
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Vertical zonation
- • Species typically grow within narrow vertical range (bands)
- • Vary in size by slope of shoreline
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Rocky intertidal: Spray Zone
- - Above high tide mark
- - Lichens, cyanobacteria, encrusting algae
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Rocky intertidal: Middle intertidal
- – Regularly submerged/emerged
- -Barnacles, Mussels, Rockweeds
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Rocky intertidal: Lower intertidal
- – Immersed most of the time
- – Very diverse, similar to subtidal
- – Echinoderms, worms, arthropods, molluscs
- – Brown, green, red algae, surf grass
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Intermediate Disturbance Hypothesis
- • Diversity maximum at intermediate levels of disturbance
- – both biotic and abiotic disturbances
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Tidepools
- • Relief from dessication
- • Allow organisms to live inhigher zones
- •Subject to variation in heatand salinity
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Soft-bottom intertidal
- Gravel, sand, mud
- • Occur where sediments accumulate
- - most animals burrow: Bivalves, worms, crustaceans
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Soft-Bottom Intertidal: Feeding
- 1. Deposit feeding (mud)
- – Clams: use siphons
- – Crabs: feeding appendages
- – Sea cucumbers, worms: “vacuum”
- – Sand dollars: use tube feet
- 2. Suspension feeding (sand)
- – Polychaete worms: tentacles
- – Polychaete worms/snails: mucus net
- 3. Scavengers:
- – Crustaceans
- 4. Predators
- – Moon snail, some worms, birds (low tide), fishes (high tide)
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Estuaries
- Freshwater + seawater
- • Link land and sea
- • Semi-enclosed
- • High productivity
- • High human impact
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Types of Estuaries
- 1. Drowned river valley
- – Formed by high sea level after last ice age
- 2. Bar-built estuary
- – Sediment build-up restricts seawater flow
- 3.Tectonic estuary
- – Sinking land floods
- 4. Fjord
- – Glacier formed
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Estuaries: Salinity
– Varies with FW/SW input
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Estuaries: Sediments
- – Suspended particles block light penetration
- – Can clog feeding surfaces and kill some organisms
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Estuaries: FW species
- – Upper estuary
- – Must adapt to tolerate salt
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Estuaries: Estuarine species
- – Throughout estuary
- – Adapted to brackish water
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Estuaries: Marine species
- – Lower estuary
- – Must adapt to less salt
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Estuaries: When salinity drops
- – Behavior: seal out water
- – Osmoconform: internal concentration varies with seawater (many invertebrates)
- – Osmoregulate: use gills, kidneys,etc. to conserve salts and eliminate excess water (some invertebrates, fishes
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Estauries: Plants
- • Land plants adapted to tolerate salt
- – Absorb salts and concentrate sugars to match external concentrations
- – Excrete excess salts via salt glands (some cordgrasses and mangroves)
- – Accumulate water to dilut esalts (succulents)
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Estuaries: Productivity
- • Highly productive
- – Nutrients (land and sea)
- – Decomposition of organic material (nutrients)
- – Nitrogen-fixation (bacteria)
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Estuaries: Primary Producers
- – Bacteria
- – Phytoplankton (benthic and planktonic)
- – Macroalgae (some habitats)
- – Plants (grasses/mangroves)
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Estuaries: Mud flat life
- 1. Infauna:
- – Bivalves: Variety of clam species
- – Crustaceans: ghost shrimp, crabs
- – Worms: innkeeper worm (shares burrow with apolychaete, crab, and fish!)
- 2. Epifauna:
- – Gastropods: mud snails, moon snails
- – Crustaceans: amphipods, shrimps, swimming crabs
- – Worms: polychaetes
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Mud flat life: Major predators
- • Fish: high tide
- • Birds: low tide
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Salt Marshes
- 1. Protect shoreline from wave action
- 2. Nutrient cycling
- 3. Water purification
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Salt Marshes: Animals
- • Bacteria
- – Decay, nitrogen fixation
- • Cyanobacteria
- • Diatoms
- • Filamentous green algae
- • Burrowing animals
- • Small invertebrates
- – Some breath air
- • Terrestrial animals
- • Marine animals
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Oyster reefs
- • Oysters form complex reef as they grow on each othersshells
- • Provide habitat for many species
- – Macroalgae
- – invertebrates
- • Clarify water (filter feeders)
- • Protect coastline
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Estuaries: Human Impact
- 1. Habitat destruction: 1/3 of US estuaries gone
- – Dredging (harbors)
- – Filling (development)
- – River diversion/damming
- – Shrimp/fish mariculture (mangroves)
- 2. Erosion/flooding
- – Climate change and sea level rise
- 3. Pollution
- – Eutrophication, oil spills
- – Trash/plastic
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Continental shelf
- Soft bottom, seagrass beds, kelp forests, coral reefs
- • Richest part of the ocean
- • 90% of global fish catch
- • Oil and minerals
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Continental shelf: Primary Production
- – Mostly phytoplankton (epipelagic)
- – Benthic diatoms and bacteria
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Continental shelf: major food source
detritus
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Continental shelf: Deposit and filter feeders:
- – Cnidarians: sea pens
- – Worms: polychaetes, peanut worms
- – Molluscs: clams
- – Crustaceans: amphipods, shrimps
- – Echinoderms: heart urchins, sand dollars, sea cucumbers, brittlestars
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Continental Shelf: Habitat modification
- • Bioturbation: move sediments, aerate
- • Tube building: stabilize substrate
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Continental Shelf: Predators
- – Snails
- – Sea stars
- – Crabs
- – Live in rocks, feed on sand:crabs, lobsters, octopus
- – Fishes:
- • rays, skates, sharks, flatfishes
- • Pelagic fishes and squid, greywhale
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Seagrass beds: Primary production
- Algae (epiphytes)
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Sea grass grazers
- – Sea turtles
- – Manatees
- – Sea urchins
- – Some parrotfishes
- – Some birds
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Hard-bottom Subtidal
- • Rich, productive, colorful
- • Space limited
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Hard-Bottom Subtidal: Productivity
Productivity: Macroalgae (and phytoplankton)
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Hard-bottom Subtidal: Grazers
– Sea urchins, chitons, sea hares, limpets,abalones, gastropods, fishes
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Algal defense
– Chemical, rapid growth rate, tough or calcareous exterio
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Hard-bottom Subtidal: Filter feeders
– Sponges, hydroids, worms, tunicates
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Hard-bottom Subtidal: Scavenger and predators
– Sea stars, octopus, crabs, lobsters, fishes,marine mammals
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Rocky subtidal
- - Cold temperatures
- -seawater
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Kelp Canopy
- • Reduces light below
- • Understory algae: smaller kelps and red algae
- • Many invertebrates and fishes
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Drift kelp is habitat for
for invertebrates, small fishes
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Other urchin predators
lobster, crabs,fishes
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Other Competitors with Urchins
abalone
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Temperature affects Kelp
↑ Temp---------kelp ↓
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Pollution: Kelp forest
- sewage/runoff
- – hurts kelp & predators
- – helps urchins
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Polar region
- • Extreme cold (air and ice), water near freezing
- • Dark winters, 24 hour light during summer
- • High summer productivity,
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Polar region: Adaptations
- – Hibernate
- – Migrate
- – Antifreeze proteins
- – Freeze tolerance
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Polar region: Metabolism
- • Ectotherm: Slow
- • Endotherm: Insulation
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Antartic
- -“coldest, windiest, driest place in the world”
- – Ozone hole: UV ↓phytoplankton, ↑genetic mutations (fish)
- – No terrestrial predators, including humans
- – No large benthic feeders
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Artic: Arctic Ocean, Russia, Canada, Greenland, Lapland, Norway, Alaska
- – Sea ice + parts of other continents
- – Human populations
- – Large benthic feeders disturb bottom
- – Terrestrial predators
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Antarctic & Arctic: Primary Production
- – Ice algae & bacteria
- – Phytoplankton
- – Some macroalgae (brown, non-kelp)
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Antarctic & Arctic: Primary consumers
– Fish, penguins, baleen whales
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Antarctic & Arctic: Secondary+ Consumers
– Seals, toothed whales, terrestrial mammals (Arctic)
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