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8/4/15
1
Yuxiang WangDepartment of Biology
Queen’s UniversityKingston, Ontario
Canada
1. Introduction¡ What is wetland?¡ Wetland classification¡ Wetland inventory
2. Wetland environments¡ Physical and chemical properties of water¡ Macrophyte canopy¡ Wetland hydrology
3. Wetland organisms¡ Microorganisms¡ Invertebrates¡ Plants¡ Animals
4. Spatial and temporal patterns¡ Spatial¡ Temporal
5. Wetland Functions¡ Primary production¡ Litter decomposition¡ Food webs¡ Nutrient cycling
6. Current and future status of wetlands¡ Losses¡ Degradation and invasive species¡ Global and pan-regional climate changes¡ restoration
¨ Area permanently or periodically inundated by shallow surface water or ground water
¨ Soils are water saturated and dominated by large and unique plants species
¨ Animals are more or less restricted to the area
¨ Different types¡ Water source¡ Landscape¡ vegetation
¨ Sustain local and regional biodiversity ¨ Primary production and litter decomposition¨ Interact in important ways with surrounding
environment (food webs, nutrient cycles, hydrology)
Highlands
Lowlands
HighlandHills
Slope
Flat
Channels
Basins
Very wet intermediate Very Dry
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¨ Anaerobic condition¡ Anaerobic soil distinguish wetlands from terrestrial systems¡ Low O2 in the water¡ Unique organisms
¨ Macrophytes¡ Large plant with terrestrial growth features – primary producer – dominant ¡ Algae maybe primary producer¡ Macrophytes and litter makes up the physical structure of wetlands and their
environment¨ Wetland organisms are adapted to chemical and physical features to allow
them to survive¡ Water fluctuation¡ Ice¡ Absence of water periodically
¨ Boundaries are arbitrary¨ Limited species are bound to wetland
¡ 2-3% angiosperm¡ 3% insects¡ 1-2% water fowls and 3% wading bird¡ Bacteria adapt to both aerobic and anaerobic condition
¨ Marine¡ Subtidal¡ Intertidal
¨ Estuarine¡ Subtidal¡ Intertidal
¨ Riverine¡ Tidal¡ Lower perennial¡ Upper perennial¡ Intermittent
¨ Lacustrine¡ Limnetic¡ Littoral
¨ Palustrine
Essential characteristicsRecurrent, sustained inundation or saturation at or near the surface with
chemical, physical and biological features reflect the above situation – hydric soil
and hydrophytic vegetation
American hierarchical wetland system
¨ Source of water¡ Ground¡ Precipitation
¨ Water chemistry¡ pH, alkalinity, base
cations¨ Biotic gradients¨ Hydrological
gradients
mesotrophicOligotrophic Eutrophic
SwampTidalmarsh
Saline wetland
Richfen
Med fen
Poor fen
Bog
Freshwatermarsh
Nutrient availabilityProductiondecomposition
¨ pH generally neutral to basic, organic or mineral soils
¨ Emergent Marsh dominated by plant communities such as reeds, cattails, and sedges
¨ Open-Water Marsh dominated by communities of floating-leaved plants such as water lilies, or submergent plants such as coontail, milfoil, and pondweed
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¨ pH basic to moderately acid, organic or mineral soils
¨ Treed Swamp: dominated by flood tolerant tree species (black ash, silver maple, cedar, etc.)
¨ Shrub or Thicket Swamp: dominated by flood tolerant shrubs (speckled alder, willow, sweetgale, buttonbush, etc.)
¨ pH basic to moderately acid, organic peaty soils, mosses. Can be rich or poor
¨ Treed Fen: typically black spruce and tamarack¨ Shrub Fen: ericaceous shrubs (blueberries,
Labrador tea, bog rosemary, leatherleaf )¨ Graminoid Fen: sedges, cottongrass, bluejoint
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¨ pH acid, organic peaty soils, Sphagnum moss dominant, low TDS
¨ Treed Bog: typically black spruce and tamarack¨ Shrub Bog: ericaceous shrubs (blueberries,
Labrador tea, bog rosemary, leatherleaf , etc.)¨ Graminoid Bog: sedges, cottongrass, bluejoint
¨ Estimate (5% land surface)¡ 2.5 x 106 km2 polar/boreal¡ 1.0 x 106 km2 sub-boreal/temperate¡ 2.0 x 106 km2 sub-tropic/tropic
¨ Human activities cause 50% losses in the world
¨ Wetlands features¡ Shallow water or saturated soils¡ Anaerobic soils¡ Unique flora and fauna adapted to environmental
conditions of in wetlandsDiffers from aquatic system – vegetation dominated by trees, shrubs, grasses, mosses, and other large plantsDiffers from terrestrial system – anaerobic soils
¨ Wetlands are characterized¡ Hydrologies¡ Geomorphological setting¡ Vegitation¡ Soils¡ Water chemistry
1. Introduction¡ What is wetland?¡ Wetland classification¡ Wetland inventory
2. Wetland environments¡ Physical and chemical properties of water¡ Macrophyte canopy¡ Wetland hydrology
3. Wetland organisms¡ Microorganisms¡ Invertebrates¡ Plants¡ Animals
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¨ 4 factors dictate the wetland environment¡ The chemical and physical properties of water¡ The morphology of the basin or channel¡ Volume of water in the basin and channel over time¡ Vegetation
¨ Liquid, 770x denser than air¡ Displace air and pulled by gravity into soil and organism¡ Aquatic Plant float in or on the water column– lack of supporting
structure¡ Animals needs morphological and behavioral adjustment to overcome
buoyancy¨ Higher specific heat capacity
¡ Organism body temp track water temp, but rather uniform¡ Large temp difference above and below plant canopy
¨ Max density at 4oC and ice float¡ Organisms survive under ice cover¡ Shallow wetlands water, some species can be eliminated temporally
¨ Light transparent¡ Provide shade, vary with entry angle¡ Scatter, shallow water means little¡ Long wavelength travel shorter distance, dissolved matter absorb short
wavelength – wetland shallow water make no difference
¨ Chemical nature and concentration of substance determine pH, hardness, nutrient content and … then affect flora and fauna
¨ Air contains 21% O2 and 0.03% CO2, temp and atm pressure dictate soluble gases
¨ Slow diffusion and high anaerobic respiration in wetland results in anaerobic condition
¨ Ability to deal with hypoxic condition is a must in wetland
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¨ Aerial and submersed plants canopies affect wetland environment condistions¡ provides 3-D structures with large surface areas to
accommodate microorganisms, invertebrates, and vertebrates
¡ Intercepts light¡ Reduces velocity of water and air¡ Produces plants litter¡ Transpires water¡ Photosynthesis and respiration alter O2 and CO2
¨ Hydrology – study of the movement and storage of water