1. Aquatic Ecosystems Fundamental Division
Freshwater
Saltwater
Aquatic Ecosystems also affected by
Dissolved oxygen level, light penetration, pH, presence/absence of currents
Three main ecological categories of organisms
Plankton- free floating
Phytoplankton – photosynthetic
Zooplankton – animal-like
Nekton - strong swimming
Benthos - bottom dwelling

2. Freshwater Ecosystems
Classified as:
LOTIC = Flowing waters, includes rivers and streams
LENTIC = “still water”, includes lakes and ponds, marshes and swamps (standing water)
Fresh water ecosystems represent just 2% of earth’s surface
Assist in recycling water back to the oceans and provide critical habitat

3. Larger streams and rivers
Rivers and Streams
Headwater streams
Larger streams and rivers

4. Estuaries, deltas, coastal ocean
Rivers and Streams
Estuaries, deltas, coastal ocean
Physical nature of aquatic ecosystems changes significantly

5. River continuum concept
Water moves from headwaters to rivers to coastal ocean
Change in physical features and food sources (abiotic differences)
Results in change in biological features and ecosystem function
In streams, organisms are adapted to fast flowing water (hooks, suctions, flattened bodies)
In rivers, organisms are adaptated for swimming (streamlined)

6. Rivers & Streams Characteristics
Headwaters: fast-flowing, many riffles, highly oxygenated, colder, bare rock substrate, low nutrient levels, rapids, waterfalls; typical fish include darters, trout, salmon
Mouth: slower, warmer, more meanders, lower oxygen levels, higher nutrient levels, more sediments with clay, silt and sand substrates; typical fish include carp, catfish, etc.

8. Lakes and Ponds Body of freshwater that does not flow Three zones
Littoral
Limnetic
Profundal
Experience thermal stratification (depending on depth)

9. Lakes and Ponds Littoral Zone - shallow water area along the shore
Limnetic Zone - open water beyond the littoral zone
Profundal Zone - beneath the limnetic zone of deep lakes

11. Thermal Stratification
Temperature changes sharply with depth
Thermocline
Temperature transition between warmer surface water and colder water at depth (difference in density)
Only present in warm months

12. Fall Turnover

14. Wetlands: Marshes and Swamps
Land with shallow, fresh water for at least part of the year
Characteristic soil and vegetation includes clay & silt (poorly drained); and species adapted to being partly submerged in water

15. Marsh Characteristics:
Marshes are periodically saturated, flooded, or ponded with water and characterized by herbaceous (non- woody) vegetation adapted to wet soil conditions.
Marshes are further characterized as tidal marshes and non-tidal marshes.

16. Tidal Marsh Characteristics:
Tidal (coastal) marshes occur along coastlines and are influenced by tides and often by freshwater from runoff, rivers, or ground water.
Salt marshes are the most prevalent types of tidal marshes and are characterized by salt-tolerant plants such as smooth cordgrass, saltgrass, and glasswort.
Salt marshes have one of the highest rates of primary productivity associated with wetland ecosystems because of the inflow of nutrients and organics from surface and/or tidal water

17. Salt Marsh Community

18. Marshes: Nontidal Marshes
Nontidal (inland) marshes are dominated by herbaceous plants and frequently occur in poorly drained depressions, floodplains, and shallow water areas along the edges of lakes and rivers.
Major regions of the United States that support inland marshes include the Great Lakes coastal marshes, the prairie pothole region, and the Florida Everglades.

19. Marshes: Nontidal Marshes
Nontidal marshes are characterized by freshwater. They typically derive most of their water from surface waters, including floodwater and runoff, but do receive ground water inputs.
Other examples of nontidal marshes:
Wet meadows commonly occur in poorly drained areas such as shallow lake basins, low-lying depressions, and the land between shallow marshes and upland areas. Precipitation serves as their primary water supply, so they are often dry in the summer. !
Wet prairies are similar to wet meadows but remain saturated longer. Wet prairies may receive water from intermittent streams as well as ground water and precipitation. ! Prairie potholes develop when snowmelt and rain fill the pockmarks left on the landscape by glaciers. Ground water input is also important. !
Playas are small basins that collect rainfall and runoff from the surrounding land. These low- lying areas are found in the Southern High Plains of the United States. !
Vernal pools have either bedrock or a hard clay layer in the soil that helps keep water in the pool. They are covered by shallow water for variable periods from winter to spring, but may be completely dry for most of the summer and fall.

20. The Everglades Original extent
Today, after extensive construction and draining of wetlands
Original extent

21. Swamps:
SWAMPS are fed primarily by surface water inputs and are dominated by trees and shrubs.
Swamps occur in either freshwater or saltwater floodplains. They are characterized by very wet soils during the growing season and standing water during certain times of the year.
Well-known swamps include Georgia’s Okefenokee Swamp and Virginia’s Great Dismal Swamp.
Swamps are classified as forested, shrub, or mangrove.

22. Mangrove Community

23. Mangrove Forest Locations…

24. Mangrove forests Tropical equivalent of salt marshes
Should cover >70% of coastlines
Services
Buffers storm energy (saves lives)
Nurseries for fish and organisms

25. Mud Flat Community

26. Estuaries Where freshwater and saltwater mix
Highly variable environment
Temperature, salinity, depth of light penetration
Highly productive
Nutrient transported from land
Tidal action circulates water
High level of light penetrates shallow water
Plants provide photosynthetic carpet
Provide abundant habitats and biodiversity

27. Ecosystem Services of Marshes Swamps, & Estuaries
Flood protection
Water filtering
Groundwater recharging
Nutrient sinks, etc.
Buffer land from storm energy (Superstorm Sandy)
Large cycling of organic matter for coast
Habitat (particularly birds)
Nurseries for Fish
Provide drought relief

28. Human Impact on Marshes Swamps, & Estuaries
Often thought of as useless
Drained and developed by humans, often times paved over
Fragmented and channelized for shipping lanes (coastal wetlands)
Excessive sedimentation due to nearby erosion
Excessive nutrient loading due to nearby farming or sewage inputs
Pollution (garbage dumped into wetlands, oil spills, etc.)

29. Protection of ecosystem (organism) services

30. Marine Ecosystems Subdivided into life zones Intertidal zone
Benthic zone
Pelagic environment
Neritic Province
Oceanic Province

31. Marine Ecosystems

32. Marine Ecosystems

33. Intertidal Zone Area of shoreline between low and high tide
Biologically productive habitat
Stressful habitat
Splash zone
Wave action
Flooding
Drying out

34. Intertidal Zone Area of shoreline between low and high tides Habitat
Sandy or rocky
Mussels
Crabs
Algae
Oysters
Barnacles
Animals must adapt to changing conditions

36. Benthic Zone
Ocean floor, extending from tidal zone to deep sea trenches
Sediment is mostly mud
Burrowing worms and clams
Three zone
Bathyal: 200m – 4000m deep
Abyssal: 4000m – 6000m deep
Hadal: 6000m – bottom of deep sea trenches

37. Productive Benthic Communities
Seagrass Beds
Present to depth of 10 m
Provide food and habitat to ecosystem
Kelp Forest
60-m long brown algae found off rocky shores
Large Biodiversity
Coral Reefs (essential fish habitat in ocean)
Built from accumulated layers of CaCO3
Colonies of millions of tiny coral animals
Similar to upside down jelly fish
Found in shallow warm water
Most diverse of all marine environments

38. Productive Benthic Communities
Left: Seagrass Bed
Right: Kelp Forest

39. Coral Reef Environments
Three types of coral reefs
Fringing reef - directly attach to continent- no lagoon
Atoll - circular reef in a lagoon
Barrier reef - separates lagoon from ocean

40. Distribution of Coral Reefs

41. Human Impact on Coral Reefs
Sedimentation
From clear-cutting, coastal construction
Overfishing, destructive fishing
Coral bleaching (stress condition)
Mining of corals as building materials
Runoff and sewage pollution
Ocean acidification and rising sea temperatures

43. Pelagic Environment All the open ocean water
Main divisions based on depth and light penetration
Euphotic zone
Surface to 150m
Sufficient light for photosynthesis
Organisms are all floaters or swimmers

44. Pelagic Environment Neritic Province
Organisms are floaters or swimmers (zooplankton, whales)
Water that overlies the continental shelf (to depth of 200m)

45. Pelagic Environment Oceanic Province
Water that overlies depths greater than 200 m
Organisms are filter feeders, scavengers and predators
No light for photosynthesis, organisms adapted for darkness
Marine snow (food particles falling from euphotic zone) support some life
Hydrothermal vent communities in deep ocean support life too

46. National Marine Sanctuaries
Protected areas in worlds oceans
NOAA administers in U.S.
“no take” and other restrictions for use

47. Human Impacts on the Ocean