34.4

34.4Aquatic Ecosystems

ObjectivesCompare and contrast ponds, streams, and estuaries.Compare conditions and typical organisms in the intertidal, neritic, and oceanic zones.Describe the abiotic and biotic factors that characterize coral reefs and hydrothermal vent communities.Vocabularyphotic zonephytoplanktonaphotic zonebenthic zoneestuarypelagic zoneintertidal zoneneritic zoneoceanic zonezooplanktonhydrothermal ventPonds and Lakesfreshwaterstanding, not flowingdivided into zones based on water depth and distance from shore

Photic Zoneshallow, close to shoreupper area further from shoresunlightphotosynthesisphytoplanktonalgaecyanobacteriawater plants

Prokaryotic, photosynthetic bacteriaeukaryotic, photosyntheticvague definitions

Aphotic Zonedeep, murky areasnot enough light for photosynthesis

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Benthic Zonebottom of any aquatic ecosystemrock, sand, sedimentorganisms feed on waste from photic zonesoft, squishiness between your toes

Streams and Riversfreshwaterflowingstream smaller than rivernear source: cold, clear, small, emptydownstream: wider, deeper, wetlands nearby, warmer, murky, more organisms

Estuariesstreams/rivers merge with oceanchange in salt concentration and temperaturenutrient-rich soilone of most productive ecosystemsbreeding, nestingcrabs, oysters, mangroves

Ocean Zonesdepth: benthic (floor), pelagic (open water above floor)photic and aphoticdistance from shore:intertidalneriticoceanic

Intertidal Zonebetween high tide an low tide linespounded by wavesexposed to sun and windspecial adaptations of organismsbarnacles

videoNeritic Zonefrom low-tide line out to edge of continental shelffairly shallowsome sunlightseaweedphytoplanktoncoral reefsmollusks, sponges, sea turtles, seals

Oceanic Zoneopen ocean from continental shelf outwardphytoplanktonzooplanktondolphinswhalessquid

Coral Reefsbeautifulbiologically diversecolonies of coral polyps, animals that secrete hard exoskeletons

videoDeep-sea Ventshydrothermal vents: spots on the ocean floor where hot gases and minerals escape from Earths interiorno sunlightchemical energyproducers: prokaryotes that use energy from sulfurtube wormsclamsvideo

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