Classification of Marine Life & Habitats OCN 201 Biology Lecture 3 1 Classifying Marine Organisms by how they get their carbon Autotrophs - use CO 2 to make organics Who: All plants, some protista, bacteria, and archaea Can use sunlight (photo-) or chemical (chemo-) energy Heterotrophs - Need to consume organic compounds Who: everything that is not autotrophic Mixotrophs - They can do both! 2
Autotrophy (photosynthesis and chemosynthesis) Energy Autotrophic Cell 6CO 2 + 6H 2 O C 6 H 12 O 6 + 6 O 2 Sugar Cells are more than sugar. Other compounds are built from simple sugars plus nutrients (Nitrogen, Phosphorous, & trace metals) 3 Respiration All living things respire..including plants! Energy heat chemical 6CO 2 + 6H 2 O Heterotrophic Cell C 6 H 12 O 6 + 6O 2 Waste Products Excretion Biomass Growth 4
Photosynthesis 6CO 2 Light + 6H 2 O Autotrophic Cell C 6 H 12 O 6 + 6O 2 5 Respiration 6CO 2 Energy + 6H 2 O heat chemical Autotrophic Cell C 6 H 12 O 6 + 6O 2 Biomass Growth 6
Mixotrophy Laboea strobila ~ 30-50 um size chlorophyll Appear in high abundance after storms in Kaneohe Bay plastid retaining; obligate mixotroph K. Selph 7 Prokaryotes Protista Fungi Plantae Animalia Photoautotrophs Chemoautotrophs Heterotrophs Mixotrophs Photoautotrophs Heterotrophs Mixotrophs Heterotrophs Photoautotrophs Heterotrophs 8
With complexity comes specialization Animalia Heterotrophs Plantae Photoautotrophs Fungi Heterotrophs Protista Photoautotrophs Heterotrophs Mixotrophs Prokaryotae Photoautotrophs Chemoautotrophs Heterotrophs Mixotrophs 9 Classifying Marine Organisms by Habitat Benthic (benthos = bottom) Pelagic (pelagos = of the sea) 10
Ocean Habitats Intertidal (littoral) zone BENTHIC PELAGIC 11 Classifying Marine Organisms by Lifestyle Benthic (benthos = bottom) Infauna Epifauna Pelagic (pelagos = of the sea) Plankton (Drifters, weak swimmers) Nekton (Swimmers) 12
Benthic Organisms Epifauna Epiflora Infauna 13 Pelagic Organisms 35 mm Nekton (all are animals) Plankton phytoplankton zooplankton bacterioplankton virioplankton 5 mm 14
Classifiying pelagic organisms by life style Holoplankton - all of life in water column Meroplankton - part of life in water column crab zoea barnacle cyprid bivalve lobster 15 Physical Divisions of the Marine Environment Supralittoral (splash zone) NERITIC OCEANIC Littoral (intertidal) Epipelagic Mesopelagic 200 m 1000 m Sublittoral Bathyal Bathypelagic Abyssal Hadal Abyssopelagic Hadalpelagic 4000 m 6000 m 16
Physical & Chemical Factors Affecting Life Pressure INCREASES with Depth Temperature & Light DECREASE with Depth & Latitude Temperature and Salinity more variable near shore Oxygen variable across depth and region Air exposure in the intertidal zone 17 Pressure Increases with Depth 18
Pressure Effects 19 Deep-diving marine mammals have collapsible lungs Sperm whale Elephant seal 20
Temperature Variations Decreases with Depth 21 Temperature Variations Decreases with Latitude POLAR TEMPERATE TROPICAL TEMPERATE POLAR 22
Water Boils Celsius 100 50 Open Ocean 32 Coastal Ocean 40 Land 58 Pure Water Freezes 0-2 -2-50 -100-88 23 Oxygen minimum zones Subarctic North Pacific (Wright et al 2012) 24
Oxygen minimum zones (Wright et al 2012) 25 Light Variations Sunlight 26
TOTAL light and COLOR Spectrum Vary with depth Red Yellow Green Blue UV 20 to 100 m about 600 m 27 Photosynthesis Feeds The Ocean Energy Food 28
83% of the biomass in the sea is in the upper 200 meters Particulate Organic Carbon (µg C per L) 0 20 40 60 80 100 120 140 0 Depth (m) 500 1000 1500 2000 2500 3000 3500 4000 29 The Pelagic Divisions (By Light) EUPHOTIC DISPHOTIC Good Light Twilight Photosynthesis! 20 to 100 m APHOTIC No Light about 600 m 30
Questions? 31