Life in the Sea and Ocean: Ecosystems, Biodiversity & Global

Generated from prompt:

presentation should be about life in the sea and the ocean. it should be so long and so complex it should be on college level

A comprehensive college-level exploration of marine environments, abiotic factors, plankton, nekton, benthic life, specialized ecosystems like corals and deep sea, higher trophic levels, food webs, human impacts, and conservation strategies for ocean

February 28, 202622 slides

Slide 1 of 22

Slide 1 - Life in the Sea and Ocean

A Comprehensive College-Level Exploration

Marine Ecosystems, Biodiversity, Interactions, and Global Challenges

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Photo by Yousef Espanioly on Unsplash

Slide 2 of 22

Slide 2 - Presentation Agenda

Marine Environments and Abiotic Factors
Plankton and Primary Production
Nekton and Benthic Life
Specialized Ecosystems (Corals, Deep Sea)
Higher Trophic Levels (Mammals, Reptiles)
Food Webs and Interactions
Human Impacts
Conservation and Future Outlook

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Photo by Md. Hasanuzzaman Himel on Unsplash

Slide 3 of 22

Slide 3 - Section 1

Marine Environments and Abiotic Factors

Understanding the physical setting for ocean life

Slide 4 of 22

Slide 4 - Key Ocean Statistics

71%: Earth's Surface
3,688 m: Average Depth
230,000+: Described Species
2.2M: Estimated Total

Source: Wikipedia

Slide 5 of 22

Slide 5 - Ocean Zonal Structure

Epipelagic (0-200m): Sunlit photic zone with highest primary production
Mesopelagic (200-1000m): Twilight zone, bioluminescence common
Bathypelagic (1000-4000m): Constant darkness, low temperatures
Abyssopelagic (4000-6000m): Extreme pressure, chemosynthesis
Hadopelagic: Deep trenches like Mariana (11km)

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Photo by Emily Wang on Unsplash

Source: Wikipedia

Slide 6 of 22

Slide 6 - Key Abiotic Factors

Temperature & Salinity Surface: 0-30°C, poles <-2°C, tropics >30°C Thermocline: Sharp gradient Salinity: 35 ppt avg (32-37), affects density & circulation

Light, Oxygen & Pressure Light penetrates ~200m (1% at 100m) Oxygen min. in thermocline Pressure: 1 atm/10m, 1000 atm at 10km Nutrients upwell in divergences

Source: Wikipedia

Slide 7 of 22

Slide 7 - Section 2

Plankton and Primary Production

Foundational producers and consumers in the ocean

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Photo by NOAA on Unsplash

Slide 8 of 22

Slide 8 - Plankton Diversity

Phytoplankton: Unicellular algae (diatoms 40% biomass, dinoflagellates); ~50-85% Earth's O2
Zooplankton: Animals from protists to metazoans (copepods dominant, krill Antarctic keystone)
Meroplankton: Temporary plankton (fish larvae, crab zoea)
Holoplankton: Permanent (forams, radiolarians, salps)
Bacterioplankton: Key in nutrient cycling

Source: Wikipedia

Slide 9 of 22

Slide 9 - Phytoplankton Examples

Diatoms: Frustules (SiO2), form blooms in cold waters
Dinoflagellates: Two flagella, some toxic (HABs)
Coccolithophores: Coccoliths reflect light (whitening)
Primary productivity rivals terrestrial forests
~50 Gt fixed carbon annually

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Photo by Niloy T on Unsplash

Source: Wikipedia

Slide 10 of 22

Slide 10 - Section 3

Nekton and Benthic Life

Mobile predators and sessile communities

Slide 11 of 22

Slide 11 - Nekton: Active Swimmers

Fish: 33K species, teleosts dominant; countercurrent exchange for O2
Chondrichthyes: Sharks/rays, cartilaginous, ampullae of Lorenzini
Cephalopods: Intelligence, chromatophores, Nautilus shelled relic
Marine Birds: Penguins, auks - regional endemics
Tunicates: Salps form chains, filter feeders

Source: Wikipedia

Slide 12 of 22

Slide 12 - Benthic Zones and Life

Intertidal: Barnacles, mussels withstand desiccation
Subtidal: Sea stars, urchins, bivalves
Shelf: Demersal fish, crabs
Slope/Abyss: Sparse, detritivores
Vents: Chemosynthetic tubeworms, clams

Source: Wikipedia

Slide 13 of 22

Slide 13 - Section 4

Specialized Ecosystems

Coral reefs, vents, and polar regions

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Photo by q u i n g u y e n on Unsplash

Slide 14 of 22

Slide 14 - Coral Reef Significance

25%: Marine Species
9M: Species/km²
500: Coral Species
1B: Dependents

Source: Wikipedia

Slide 15 of 22

Slide 15 - Deep Sea Mysteries

> With every drop of water you drink, thousands of water molecules that dinosaurs drank pass through your gut.

— Sylvia Earle (adapted for ocean context)

Source: Wikipedia, Sylvia Earle

Slide 16 of 22

Slide 16 - Section 5

Higher Trophic Levels

Marine mammals, reptiles, and birds

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Photo by Todd Cravens on Unsplash

Slide 17 of 22

Slide 17 - Evolution of Marine Mammals

50 Ma: Archaeocetes Amphibious ancestors like Pakicetus to fully aquatic Basilosaurus 40 Ma: Mysticeti Baleen whales evolve filter feeding 34 Ma: Odontoceti Toothed whales, echolocation develops 25 Ma: Pinnipeds Seals, sea lions from mustelids 15 Ma: Sirenians Manatees, dugongs from proboscideans Present: ~130 spp Cetaceans, pinnipeds, sirenians, marine otters

Source: Wikipedia

Slide 18 of 22

Slide 18 - Section 6

Food Webs and Interactions

From producers to apex predators

Slide 19 of 22

Slide 19 - Marine Trophic Cascade

Trophic Level	Key Organisms	Energy Efficiency
Producers	Phytoplankton, seaweeds	~1% solar captured
Primary Consumers	Zooplankton, herbivores	10% transfer
Secondary Consumers	Filter feeders, small planktivores	10%
Tertiary Consumers	Carnivorous fish	10%
Apex Predators	Sharks, marine mammals	Keystone role