Aquatic Biomes
This can be found on my website
What factors influence the kind of
life an aquatic biome contains?
 Salinity
(how much salt)
 Depth (related to how much sunlight)
 Speed of water flow
 D.O. (dissolved oxygen levels)
Zones of Freshwater Lakes
Littoral zone- shore line. Nutrient rich and diverse.
Contains emergent plants (plants growing out of the water)
Benthic zone- muddy bottom.
Limnetic zone – open water, floating algae, photic zone
Profundal Zone
Only found in deep lakes
Open water, but no sunlight reaches here
(aphotic)
Nutrient levels

Oligotrophic – Nutrient poor/oxygen rich. Often sources
that feed it are glaciers, mountainous regions.

Eutrophic- Nutrient rich/oxygen poor. Fed by steams
with lots of dissolved minerals but the decaying organic
matter increases oxygen demand.

Mesotrophic: somewhere in between
Freshwater- lakes and ponds


Often, newly formed lakes start as oligotrophic and
become eutrophic.
Eutrophication can be accelerated by pollution that
cause algal blooms. (fertilizer runoff, sewage)
Freshwater- wetlands

covered in water for at least part of the year.
Ecosystem services:
 help to clean and filter water.

help to reduce flooding because they can absorb
much water.
Wetlands - Marshes

Marshes are freshwater wetlands that have
mostly non-woody plants.
Wetlands - bogs

A bog is an acidic wetland with low nutrients.

Lots of dead moss and other material builds up.  peat
Wetlands - swamps

Swamps are freshwater wetlands that contain
woody plants (wetland forest)
Wetlands - Estuaries

An estuary is where a river runs into an ocean.
 There is varying salinity in an estuary.

May contain salt marsh habitat (marsh with salty
water)
Brackish = mix of saltwater and freshwater
Mangrove swamp (forest)

Saltwater swamp. Contain mangrove trees (trees
tolerant to salt water)
Marine (ocean) biomes


Coastal zone – Shoreline out to edge of continental shelf.
Intertidal zone – where there are tides, submerged for part
of the day, crashing waves (part of coastal zone)

Pelagic zone – open ocean. Not near shore, not the
bottom muddy area. 3 parts to the pelagic zone (on next
slide)

Benthic zone – bottom muddy area.

Coral reefs - buildup of dead coral skeletons provides
habitat. Found in shallow, warm marine areas. Brightly lit so
lots of productivity. Probably the most biodiverse biome on
the planet!
Biological Zones in Pelagic Zone



Euphotic zone: brightly lit surface layer.
 Nutrient levels low, dissolved O2 high, photosynthetic
activity.
Aphotic zone: little or no sunlight = no photosynthesis
Bathyal zone: dimly lit middle layer (twilight zone)
 No photosynthetic activity, zooplankton and fish live
there and migrate to euphotic zone to feed at night.
Abyssal zone: dark bottom layer.
 Very cold, little dissolved O2.
Euphotic Zone
Continental
Shelf
Photosynthesis
Pelagic zone (Open Ocean)
Bathyal Zone
Aphotic Zone
Abyssal
Zone
Darkness
Coastal
Zone