Wetlands of the World

Wetlands of the World

• Wetland Ecology • Wetlands of the World • Extent of the world’s wetlands • 7 – 10 million km2 ~ 5 to 8 percent of land surface • North America 43.6 million ha. (lower 48) – 71 million ha. in Alaska – 127 million ha. in Canada – 30 % of world’s wetlands • All are impacted by humans but remain functional • Wetlands include: • Swamps • Bogs • Marshes • Mires • Fens Every continent except Antarctica (from tropics – tundra) • Definitions • Swamp – Tree/shrub dominated wetland • Bog – peat accumulating wetland, no significant in/outflow, supports bryophytes • Marsh – Frequently/permanently flooded, supports emergent vegetation • Mire – Synonymous with any peat accumulating wetland (Europe) • Fen – Peat accumulating wetland, receives drainage from mineral soil, marsh-like vegetation • Peatland – Wetlands that accumulate organic matter • Slough – A swamp/shallow lake system in north/Midwest (slowly flowing shallow swamp/marsh in southeast U.S.) • Worldwide Wetland Losses • North America Wetland Changes • 53% have been lost since 1780’s – 1980’s • States with > 80% loss – Illinois, Indiana, Iowa, Kentucky, Missouri, Ohio + California – Collectively a loss of 14.1 million ha in 200 yrs – What caused this loss? • States with highest densities of wetlands – Minnesota, Illinois, Louisiana, and Florida had greatest rate of loss of total area. – 2.6, 2.8, 3.0, & 3.8 million ha respectively – Canadian Wetland Changes • Less population density • 65 – 80 % loss near Atlantic & Pacific regions • 71% loss in the lower Great Lakes • 71% loss in the prairie pothole region • North America • Florida Everglades from Lake Okeechobee – Florida Bay has 3 major types of wetlands – 34,000km2 area • The Everglades • Big Cypress Swamp • Coastal Mangroves • Everglades • Dominated by Cladium jamaicense (sawgrass) • Can be flooded >1m in summer • Common tree islands (hammocks) • Hardwoods, palms, orchids, and other air plants common • Big Cypress Swamp • Expansive area • Dominated by Taxodium spp. interspersed with pine flatwoods & wet prairie • 125 cm of rainfall/yr. • Coastal Mangrove • Forms impenetrable thickets where sawgrass and cypress swamps meet saline waters of the Atlantic • Everglades is the site of the largest wetland restoration project ever conducted • ½ lost to agriculture • 8 billion dollar effort • Okefenokee Swamp • Means “Land of Trembling Earth” • Atlantic Coastal Plain of southeastern GA. • 1,750km2 • Headwaters of two rivers: – Suwanee River – St. Mary’s River • Six major wetland communities comprise the Okefenokee • Pond Cypress Forest • Emergent & Aquatic bed prairie • Broad-Leaved Evergreen forest • Broad-leaved shrub wetland • Mixed cypress forest • Black gum forest – Taxodium distichum, Nyssa sylvatica, Magnolia virginiana are the dominant trees – Panicum, Carex, & Nymphaea are dominant herbaceous plants • Carolina Pocosins • Mean “swamp on a hill” • Evergreen shrub-bogs found on Atlantic Coastal Plain: Virginia – northern Florida • Typically nutrient poor; were once categorized as bogs in 1954 survey • Pinus serotina is dominant pine • Said to “grow on waterlogged, acid, nutrient poor, sandy or peaty soils located on flat topographic plateaus, usually removed from large streams • Great Dismal Swamp • Northern most ‘southern swamp’ • Once primarily bald-cypress gum swamp that contained extensive stands of Chamaecyparis thyoides (white cedar) • Lake Drummond found in center of swamp • George Washington built a canal to establish farms on the basin – Failed miserably • Swamp Rivers of the South Atlantic Coast • Cut by large rivers that drain the Piedmont – Roanoke, Chowan, Little Pee Dee, Great Pee Dee, Lynches, Black, Santee, Congaree, Altamaha, Cooper, Edisto, Combahee, Coosawhatchie, & Savannah • Made up of several lake-wetland systems – > 500,000 of these – Suggested to be made from meteor showers, wind or groundwater flow • Congaree Swamp in S.C. includes the world’s largest virgin cypress-tupelo swamp • Prairie Potholes • North Dakota, South Dakota, & Minnesota – Manitoba, Saskatchewan, & Alberta • Only 10% of original wetlands remain • Formed by glacial action • Know for waterfowl habitat and ties nicely with the Mississippi River as major summer breeding area – Migratory waterfowl fly by us to reach wintering grounds – 50 – 75% of waterfowl come from this region • Nebraska Sandhills & Great Plains Playas • Largest stabilized dune field in the Western Hemisphere • Much has been lost to agriculture • 25,000 playas (Spanish for beach) • The Great Black Swamp • Northwestern Ohio • Named for the rich, black muck in poorly-drained areas • Louisiana Delta • One of the most wetland-rich regions of the world • Atchafalaya River is characteristic of the riverine portion • Has long history of human intervention • Freshwater & Saltwater wetlands are decreasing at a rapid rate ~ 60 – 100 km2 /yr – What is the cause of this? • Plan 2050 will sink billions of dollars into rebuilding barrier islands lost due to dredging and levee control – i.e. sediment losses • San Francisco Bay • One of the most impacted wetlands in the U.S. • 95% of marshes have been destroyed • Dominated by Spartina foliosa and Salicornia virginica • Demise began after the gold rush • Great Lakes Wetlands/St. Lawrence Lowlands • Important habitat for waterfowl • Snow geese leading to decline of marshes • Mexico Wetlands • Underrepresented in # and area of Ramsar wetlands – Only 7 sites designated in 2001 – Now 65 Ramsar sites covering 5.3 million ha • Cuatro Ciénegas is one of driest areas in Chihuhuan Desert but contains 200 springs – Pozas (small springs) – Lagunaas (larger spring-fed lakes) – Playa Lakes (lakes without outlets) – Ciénegas (shallow swamps) – Manmade channels • Central & South America • Orinoco River Delta • The Llanos • The Pantanal • The Amazon • Oronoco River Delta • Economy based on cattle farming, cacao and palm heart canning. • Grazing & illegal hunting have decimated area’s flora & fauna • The Llanos • Sedimentary basin • Winter wet season and summer dry season – Wetland dominated by savanna grasslands & scattered palms rather than floodplain forests • Pantanal • One of the largest wetlands of the world • Geographic center of South America • 4x size of the Everglades • Bird richest wetland in the world – 463 species of birds – 13 species of herons & egrets – 3 stork species – 6 ibis species – 6 duck species – 11 rail species – 5 kingfisher species • Jabiru found here (largest bird in the western hemisphere • Largest rodent found here • Amazon • Wetlands cover 25% of the 7million km2 Amazon basin • Flooding reaches 15m in some areas • Europe • Mediterranean Sea Deltas – Rhone River Delta – The Camargue one of the world’s 25 major flamingo nesting sites – Rhine River in the Netherlands is the most hydraulically controlled locations on Earth • Inland Deltas – Volga River (on edge of Caspian Sea) forms one of the largest inland deltas • Large percentage of the world’s sturgeon comes from the Caspian Sea • Peatlands in Ireland, Scandinavia, Finland, & northern Russia – ~20% of Europe – Endla & Berezinski Bog are best examples • Okavango Delta is divided into 3 hydrologic zones – Permanent swamp – Seasonally flooded floodplains – Occasional floodplains • 71 species of fish found here • Congolian Swamp Forests • Largest / least studied swamp forest in world • Congo River has 2nd highest flow of any river • Forests remain because of isolation – Lowland gorilla – Forest elephants – Forest buffalo • Middle East • Mesopotamian Marshlands of southern Iraq & Iran – Tigris & Euphrates rivers • Dams & drainage systems have eliminated flood-pulses essential for wetland maintenance • Australia / New Zealand • Billabongs – Not permanent (intermittent & seasonal) • Asia • Western Siberian Lowlands – Peatlands important for carbon sequestration • Indian Freshwater Marshes – Many natural disasters due to anthropogenic manipulation • Asian River Deltas – Mud flats, swamp forests, arctic tundra & mangrove forests • China – Many are artificial (rice paddies) & fish ponds .

View Full Text

Details

  • File Type
    pdf
  • Upload Time
    -
  • Content Languages
    English
  • Upload User
    Anonymous/Not logged-in
  • File Pages
    7 Page
  • File Size
    -

Download

Channel Download Status
Express Download Enable

Copyright

We respect the copyrights and intellectual property rights of all users. All uploaded documents are either original works of the uploader or authorized works of the rightful owners.

  • Not to be reproduced or distributed without explicit permission.
  • Not used for commercial purposes outside of approved use cases.
  • Not used to infringe on the rights of the original creators.
  • If you believe any content infringes your copyright, please contact us immediately.

Support

For help with questions, suggestions, or problems, please contact us