Aquatic Ecosystems Freshwater Ponds & Lakes Streams & Rivers Wetlands Marine Oceans Coral Reefs Estuaries Freshwater Ponds & Lakes Streams & Rivers Wetlands 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 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 divided into three different “zones” determined by depth and distance from the shoreline littoral zone limnetic zone profundal 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 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 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 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 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 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 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 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 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 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 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 Wetlands Wetlands are areas of standing water that support aquatic plants Marshes, swamps, and bogs are all considered wetlands Wetlands Plants adapted to the very moist and humid conditions are called hydrophytes Pond lilies Cattails Tamarack Gum Sedges Black Spruce Cypress 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 River Otter Wetlands Crayfish Catfish Damselfly Dragonfly Snails Leech Bluegill Sculpin Minnow Snakes Frog Great Blue Heron Canadian Goose Mayfly Bass Turtle Aquatic Ecosystems Marine Oceans Coral Reefs Estuaries 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 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 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 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 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 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 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 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 http://oceanlink.island.net/oinfo/deepsea/meso.html "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 Big Scale - ambush predator ctenophore – related to jellyfish 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 http://oceanlink.island.net/oinfo/deepsea/meso.html 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 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 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 Deep Water Squid Basketstar Sea Pig Sea Spider Shrimp Winged Sea Cucumber Medussa Deep Sea Smoker - 648°F Deep-sea Anemone Hydrothermal Vent 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 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 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 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 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 = Coral Reef 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 Phytoplankton Microscopic Basis for all ocean food chains Coral Reef Plants Algae Green Red Brown algae takes many forms 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 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 Coral Reef Creatures Coral polyps Tentacles Digestive sac Connecting filaments Skeletal body Coral Reef Creatures Symbiotic relationships Coral with algae Clown fish with sea anemones 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 Sample Food Chain Starfish Coral Octopus Zooplankton Moray Eel Phytoplankton Endangered Coral Reefs Major threats to coral reefs include: Ocean pollution Dredging off the coast 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 http://www.epa.gov/owow/estuaries/about1.htm 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 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. 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. 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 http://www.epa.gov/owow/estuaries/about1.htm 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 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. 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 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
