Aquatic Ecosystems : Aquatic Ecosystems Freshwater
Ponds & Lakes
Streams & Rivers
Wetlands
Marine
Oceans
Coral Reefs
Estuaries
Freshwater : Freshwater Ponds & Lakes
Streams & Rivers
Wetlands
Freshwater : Freshwater Freshwater is defined as having a low salt concentration—usually less than 1%
Plants and animals in freshwater regions are adjusted to the low salt content and would not be able to survive in areas of high salt concentration (i.e, ocean)
Ponds and Lakes : Ponds and Lakes range in size from just a few square meters to thousands of square kilometers
ponds may be seasonal, lasting just a couple of months (such as sessile pools)
lakes may exist for hundreds of years or more
may have limited species diversity since they are often isolated from one another and from other water sources like rivers and oceans
Ponds and Lakes : Ponds and Lakes divided into three different “zones” determined by depth and distance from the shoreline
littoral zone
limnetic zone
profundal zone
Littoral Zone : Littoral Zone warmest since it is shallow and can absorb more of the Sun’s heat
sustains a fairly diverse community, which can include several species of algae (like diatoms), rooted and floating aquatic plants, grazing snails, clams, insects, crustaceans, fishes, and amphibians
the egg and larvae stages of some insects are found in this zone
vegetation and animals living in the littoral zone are food for other creatures such as turtles, snakes, and ducks
Limnetic Zone : Limnetic Zone near-surface open water surrounded by the littoral zone
well-lighted (like the littoral zone) and is dominated by plankton, both phytoplankton and zooplankton
plankton are small organisms that play a crucial role in the food chain – most life would not be possible without them
variety of freshwater fish also occupy this zone
Profundal Zone : Profundal Zone Plankton have short life spans—when they die, they fall into the deep-water part of the lake/pond
much colder and denser than the other two
little light penetrates all the way through the limnetic zone into the profundal zone
animals are decomposers
Ponds and Lakes : Ponds and Lakes Temperature
varies seasonally.
Summer
from 4° C near the bottom to 22° C at the top
Winter
from 4° C while the top is 0° C (ice)
between the two layers is a narrow zone called the thermocline where the temperature of the water changes rapidly with depth
Ponds and Lakes : Ponds and Lakes during the spring and fall seasons is a mixing of the top and bottom layers resulting in a uniform water temperature of around 4° C
mixing also circulates oxygen throughout the lake
many lakes and ponds do not freeze during the winter resulting in the top layer being a little warmer
Ponds and Lakes : Ponds and Lakes ice can develop on the top of lakes during winter
blocks out sunlight and can prevent photosynthesis
oxygen levels drop and some plants and animals may die
called "winterkill."
Ponds and Lakes : Ponds and Lakes
Streams & Rivers : Streams & Rivers bodies of flowing water moving in one direction
found everywhere—they get their start at headwaters, which may be springs, snowmelt or even lakes
travel all the way to their mouths, usually another water channel or the ocean
Watershed : Watershed describes an area of land that contains a common set of streams and rivers
drains into a single larger body of water, such as a larger river, a lake or an ocean
Streams & Rivers : Streams & Rivers characteristics change during the journey from the source to the mouth
temperature is cooler at the source than it is at the mouth
water is also clearer, has higher oxygen levels, and freshwater fish such as trout and heterotrophs can be found there
Streams & Rivers : Streams & Rivers Towards the middle part of the stream/river, the width increases, as does species diversity—numerous aquatic green plants and algae can be found
Streams & Rivers : Streams & Rivers toward the mouth the water becomes murky from all the sediments that it has picked up upstream
decreasing the amount of light that can penetrate through the water
less light
less diversity of flora
lower oxygen levels
fish that require less oxygen, such as catfish and carp, can be found
Streams & Rivers : Streams & Rivers
Wetlands : Wetlands Wetlands are areas of standing water that support aquatic plants
Marshes, swamps, and bogs are all considered wetlands
Wetlands : Wetlands Plants
adapted to the very moist and humid conditions are called hydrophytes
Pond lilies Cattails Sedges
Tamarack Black Spruce
Gum Cypress
Wetlands : Wetlands highest species diversity of all ecosystems
many species of amphibians, reptiles, birds (such as ducks and waders), and furbearers can be found in the wetlands
not considered freshwater ecosystems as there are some, such as salt marshes, that have high salt concentrations—these support different species of animals, such as shrimp, shellfish, and various grasses
Wetlands : Wetlands
River Otter
Damselfly Dragonfly Mayfly
Crayfish Snails Leech Bluegill Bass
Catfish Sculpin Minnow Snakes
Frog Turtle
Great Blue Heron Canadian Goose
Aquatic Ecosystems : Aquatic Ecosystems Marine
Oceans
Coral Reefs
Estuaries
Marine : Marine cover about three-fourths of the Earth’s surface and include oceans, coral reefs, and estuaries
algae supply much of the world’s oxygen supply and take in a huge amount of atmospheric carbon dioxide
evaporation of the seawater provides rainwater for the land
Oceans : Oceans largest of all the ecosystems
dominate the Earth’s surface
separate zones
Intertidal
Pelagic
Abyssal
Benthic
great diversity of species
richest diversity of species even though it contains fewer species than there are on land
Oceans : Oceans
Intertidal Zone : Intertidal Zone where the ocean meets the land
sometimes submerged and at other times exposed
waves and tides come in and out
communities are constantly changing
Intertidal Zone : Intertidal Zone rocky coasts
stratified vertically
Where only highest tides reach
a few species of algae and mollusks
submerged during high tide
more diverse array of algae and small animals, such as herbivorous snails, crabs, sea stars, and small fishes
bottom of the intertidal zone
only exposed during the lowest tides, many invertebrates, fishes, and seaweed can be found
Intertidal Zone : Intertidal Zone sandier shores
not as stratified
waves keep mud and sand constantly moving
very few algae and plants can establish themselves—the fauna include worms, clams, predatory crustaceans, crabs, and shorebirds.
Wave Regions : Wave Regions much stronger than wind
decide what grows where
shores classified by amount of wave action
Exposed shores – receive full brunt of the ocean for most or at least some of the time
Semi-exposed shores – sheltered by barrier islands but still have to cope with waves
Sheltered shores – shelter of peninsulas and inshore islands
Enclosed shores
river mouths and estuaries
completely sheltered by either a protective rocks or a sand bar
Pelagic – Open Ocean : Pelagic – Open Ocean waters further from the land, basically the open ocean
generally cold though it is hard to give a general temperature range since, just like ponds and lakes, there is thermal stratification with a constant mixing of warm and cold ocean currents
Epipelagic – Open Ocean : Epipelagic – Open Ocean extends down to around 200m
lowest depth that light can penetrate
flora in the epipelagic zone include surface seaweeds
fauna include many species of fish and some mammals, such as whales and dolphins
many feed on the abundant plankton
Mesopelagic Zone : Mesopelagic Zone "twilight zone" of the ocean
photic zone above
darkness below
food becomes scarce – some animals
migrate up to the surface at night to feed
rely on food that falls down from above
eat each other
sometimes the only things to eat may be bigger than the hunter
developed long sharp teeth,
expandable jaws and stomachs http://oceanlink.island.net/oinfo/deepsea/meso.html
Slide39 : http://oceanlink.island.net/oinfo/deepsea/meso.html
ctenophore – related to jellyfish
Big Scale - ambush predator cilia can be illuminated
Firefly squid
three kinds of photophores
Hatchet Fish
only a few inches long
Viperfish
specially adapted hinged skull
Dragonfish - stomachs hold big meals
Snipeel
up to 1.2m Siphonophores are colonies of animals
related to jellyfish
best known is Portugese Man of War
Bathypelagic Zone : Bathypelagic Zone extends down from 1000 to 4000m
only light is from bioluminescent organisms
only food is what trickles down from above, or from eating other animals
water pressure at this depth is considerable (~100 – 400 atmospheres)
most animals are either black or red in color
very little blue/green light penetrates this deep – red is not reflected and looks black
Slide41 :
Narcomedusa
Vampire Squid
Snake Dragon
Angler Fish
Amphi - crustacean
Ctenophore – voracious predator
Deepstaria very slow swimmers, no tentacles, close flexible bells (up to a meter across) around their prey
Big Red
grows to over
a meter across
Abyssopelagic Zone - the Abyss : Abyssopelagic Zone - the Abyss 4000m to the sea floor
only zone deeper than this is the hadal zone
areas found in deep sea trenches and canyons
home to pretty inhospitable living conditions
near- freezing temperatures
crushing pressures
Slide43 : Deep Water Squid
Basketstar
Sea Pig Sea Spider
Shrimp
Winged Sea Cucumber
Medussa
Deep Sea Smoker - 648°F
Deep-sea Anemone Hydrothermal Vent
Slide45 : Ballina Angelfish
Beaked Salmon
A deepsea anglerfish (no common name)
Duckbilled Eel
A fanfin anglerfish
Fangtooth
Gilbert's Halosaur
Gulper Eel
Hammerjaw
Largescale New Laternfish
Longray Spiderfish
Portuguese Dogfish
Sharpnose Sevengill Shark
Short-tail Torpedo Ray
Silver Lighthouse Fish
A snaggletooth (no common name)
Snubnosed Eel
Southern Spineback
Sparkling Slickhead
Spiky Oreo
Stoplight Loosejaw
Triplewart Seadevil
Viperfish
http://www.amonline.net.au/fishes/about/fieldwork/norfanz/
The Coral Reef Biome : A Look at a Marine Biome
Created by
Terri Street The Coral Reef Biome
What Is a Coral Reef? : What Is a Coral Reef? A structure formed by coral polyps, tiny animals that live in colonies.
Coral polyps form a hard, stony, branching structure made of limestone.
New polyps attach to old coral and gradually build the reef.
Types of Coral Reefs : Types of Coral Reefs Fringing reefs
Submerged platforms of living coral extending from the shore into the sea
Barrier reefs
Follow the shore but are separated from it by water
Great Barrier Reef is world’s largest
Types of Coral Reefs : Types of Coral Reefs Atolls
Ring-shaped islands of coral in open sea
Form on submerged mud banks or volcano craters
Surround a seawater lagoon
Channels connect lagoon to the sea
A World of Coral Reefs : A World of Coral Reefs
Coral Reef Climate : Coral Reef Climate Usually found near land in shallow, warm salt water
Lots of light
Tropical temperatures, averaging 70°-85° F
Most coral cannot survive below 65° F
Coral Reef Plants : Coral Reef Plants Phytoplankton
Microscopic
Basis for all ocean food chains
Coral Reef Plants : Coral Reef Plants Algae
Green
Red
Brown algae takes many forms
Coral Reef Plants : Coral Reef Plants Seaweed and Sea grasses
Brown seaweed
Sea grass
Shoal grass
Turtle grass
Fascinating Fact: The Great Barrier Reef : World’s largest coral reef
Over 1257 miles long
Off the northeast coast of Australia
Only grows about one inch per year
Fascinating Fact: The Great Barrier Reef
The Great Barrier Reef: Home to… : 1500 species of fish
400 different types of coral
4,000 mollusks
500 species of seaweed
215 species of birds
16 species of sea snake
6 species of sea turtle
Whales visit during winter The Great Barrier Reef: Home to…
Coral Reef Creatures : Coral Reef Creatures Coral polyps
Tentacles
Digestive sac
Connecting filaments
Skeletal body
Coral Reef Creatures : Coral Reef Creatures Symbiotic relationships
Coral with algae
Clown fish with sea anemones
Coral Reef Creatures : Coral Reef Creatures Tropical fish
Angel fish
John Dory
Butterfly fish
Sea horse
Octopus
Reef shark
Fascinating Fact: The Sea Horse : Very weak swimmers
Female lays eggs, male carries them in pouch till birth
Only animal in which the father gives birth
Body covered with armored plates
Fascinating Fact: The Sea Horse
Sample Food Chain : Sample Food Chain
Endangered Coral Reefs : Endangered Coral Reefs Major threats to coral reefs include:
Ocean pollution
Dredging off the coast
Endangered Coral Reefs : Endangered Coral Reefs Other dangers:
Careless collection of coral specimens
Sedimentation
Inhibits growth of coral polyps
Inhibits algae growth
Upsets balance of the biome
Estuaries : Estuaries enclosed body of water formed where freshwater from rivers and streams flows into the ocean, mixing with the salty sea water
estuaries and the lands surrounding them are places of transition from land to sea, and from fresh to salt water
although influenced by the tides, estuaries are protected from the full force of ocean waves, winds, and storms by the reefs, barrier islands, or fingers of land, mud, or sand that define an estuary's seaward boundary http://www.epa.gov/owow/estuaries/about1.htm
Estuaries are semi-enclosed bodies of water where fresh water from the land mixes with sea water. : Estuaries are semi-enclosed bodies of water where fresh water from the land mixes with sea water. Estuaries originate as: drowned river valleys, fjords, bar-built estuaries, and tectonic estuaries.
Salinity typically grades from normal marine salinity at the tidal inlet to fresh water at the mouth of the river.
Estuaries can be subdivided into three types based upon the relative importance of river inflow and tidal mixing. : Estuaries can be subdivided into three types based upon the relative importance of river inflow and tidal mixing. Salt-wedge estuaries are dominated by the outflow from rivers.
Partially-mixed estuaries are dominated by neither river inflow nor tidal mixing.
In well-mixed estuaries tidal turbulence destroys the halocline and water stratification.
Because river discharge and tidal flow vary, conditions within an estuary can also change, being well-mixed when river flow decreases relative to tidal mixing, to becoming a salt-wedge estuary at times of maximum river discharge.
The widely fluctuating environmental conditions in estuaries make life stressful for organisms. : The widely fluctuating environmental conditions in estuaries make life stressful for organisms. Estuaries are extremely fertile because nutrients are brought in by rivers and recycled from the bottom because of the turbulence.
Stressful conditions and abundant nutrients result in low species diversity, but great abundance of the species present.
Despite abundance of nutrients, phytoplankton blooms are irregular and the base of the food chain is detritus washed in from adjacent salt marshes.
The benthonic fauna strongly reflects the nature of the substrate and most fishes are juvenile forms living within the estuary until they mature and migrate to the ocean.
Estuaries : Estuaries
Estuaries are sometimes called “marine nurseries”
habitats for many juvenile organisms, especially for fishes
many fish are born and grow up in estuaries
migrate to the open ocean http://www.epa.gov/owow/estuaries/about1.htm
Lagoons are isolated to semi-enclosed, shallow, coastal bodies of water that receive little if any fresh water inflow. : Lagoons are isolated to semi-enclosed, shallow, coastal bodies of water that receive little if any fresh water inflow. Lagoons can occur at any latitude and their salinities vary from brackish to hypersaline depending upon climate and local hydrology.
Bottom sediments are usually sand or mud eroded which was from the shoreline or swept in through the tidal inlet.
In the tropics, the water column is typically isothermal.
In the subtropics, salinity generally increases away from the inlet and the lagoon may display inverse flow.
Salt marshes are intertidal flats covered by grassy vegetation. : Salt marshes are intertidal flats covered by grassy vegetation. Marshes are most commonly found in protected areas with a moderate tidal range, such as the landward side of barrier islands.
Marshes flood daily at high tide and then drain through a series of channels with the ebb tide.
They are one of the most productive environments.
Marshes can be divided into two parts: Low salt marshes and High salt marshes.
Distribution and density of organisms in salt marshes strongly reflects availability of food, need for protection, and frequency of flooding.
Mangroves are large woody trees with a dense, complex root system that grows downward from the branches : Mangroves are large woody trees with a dense, complex root system that grows downward from the branches Mangroves are the dominant plant of the tropical and subtropical intertidal area
Distribution of the trees is largely controlled by air temperature, exposure to wave and current attack, tidal range, substrate and sea water chemistry
Detritus from the mangrove forms the base of the food chain
Bibliography : Bibliography http://www.ucmp.berkeley.edu/glossary/gloss5/biome/index.html
http://www.enchantedlearning.com/biomes/marsh/freshwater.shtml
http://mbgnet.mobot.org/
http://www.runet.edu/~swoodwar/CLASSES/GEOG235/biomes/intro.html
http://archive.globe.gov/sda-bin/wt/ghp/tg+L(en)+P(seasons/Miniinvestigation)
http://www.panda.org/about_wwf/where_we_work/ecoregions/global200/pages/home.htm
“Coral Reefs.” World Book. Chicago: World Book, 1998. Vol. 4, p. 257.
“Coral Reefs.” http://kidscience.about.com/kids/kidscience/cs/coralreefs/