2. Wetlands are lands where saturation with water is the dominant factor determining the nature of soil development and the types of plant and animal communities living in the soil and on its surface (Cowardin, December 1979). Those areas that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, bogs and similar areas (Clean Water Act)

4. Types of wetlands Marshes (soft-stemmed vegetation) Swamps (mostly woody plants) Bogs (freshwater wetlands, acidic, peat deposits, evergreen trees and shrubs, sphagnum) Fens (freshwater wetlands, fed by mineral-reach waters, neutral or alkaline, peat deposits, grassy vegetation)

5. North Florida saltmarshes Formed along the edges of estuaries Buffer against brief storm surges (protection of the shore against degradation) Nurseries for fish, crustaceans, mollusks

6. Vasyugan swamp or bog (Western Siberia) The largest swamp in northern hemisphere (53,000 km²) formed 10,000 years ago, has been growing in size since then. Main source of freshwater in the region Huge peat deposits (carbon sink)

7. Pantanal – tropical wetland

8. Wetland functions Water storage and groundwater replenishment Shoreline stability Flood control Water filtration Biological productivity Carbon storage (carbon sink) Methane production

9. Water storage and groundwater replenishment Water is collected, stored and slowly released to aquifers or surface water

11. Shoreline stabilization Roots anchor in sediment, preventing erosion Vegetation diminishes the wave action

12. Flood control

16. Water filtration Nutrient uptake (including excess from fertilizers etc.) and storage by plants Sediment traps Biofiltration and removal of toxic substances by plant roots and bacteria

17. Biological productivity Wetlands are among most productive ecosystems in the world, comparable to tropical rainforests and coral reefs Provide habitat to diverse species

18. Carbon storage

19. Methane production

22. Major global change agents influencing wetlands Sea-level rise Global warming Direct anthropogenic influence