A. Based on temperature and precipitation

B. Five groups

A Humid tropical, winterless

B Dry: ET exceeds precip

C Humid mid-latitude, mild winters

D Humid mid-latitude, severe winters

E Polar, summerless

C. Climatic wetlands form primarily in two regions

D Cold, high latitudes

Cold keeps ET down, ties up water in ice

Short growing season, low transpiration

Flat terrain, easily flooded by ice and snowmelt

Slow decomposition leads to peat buildup

A Humid tropics

Rainfall is regular and substantial

Productivity is high

Flooding caused by lots of water, regularly applied

Peat less likely to form because of high rates of decomposition

May form in flooded, salty, or toxic soils


A. North America

1. Canada and Alaska


Boreal forest

Hudson Bay lowlands

Complex montane, riverine, coastal systems in Alaska

Prairie potholes in Canada

2. USA

East coast estuaries

Florida sawgrass marsh

Mississippi R. delta

Potholes and playas

California internally drained systems

Western riparian systems

Pacific coast estuaries

B. Mexico, Central America, Caribbean

1. Mexico

Main wetlands on coast

2. Caribbean

Most extensive wetlands on larger islands

Islands with +1000m mountains create rivers

Much converted to rice farming

3. Central America

Complex systems on Caribbean side (70% of precip)

Mangroves on Pacific side (30% of precip)

Much conversion to shrimp mariculture

C. South America

1. Northern South America

Amazon basin

Maranhão and rivers in east Brasil

Llanos of Orinoco drainage

2. Southern South America

Flooded Pantanal feeds Paraguay R.

Parana R. runs south to join Paraguay R.

Puna: Andean altiplano above 10,000

D. Europe

1. Fennoscandia, UK, N. Russia

Ice and precipitation dominated systems

Palsa-, blanket-, aapa-, raised-, polygon bogs (mires)

2. Coastal shallows

Wadden Sea

3. Floodplain systems

Loire, Rhine, Vistula, Danube, Dnieper, Dniester, Volga

4. Mediterranean basin

Mostly deltas: Rhone, Po, Nile

E. Middle East

1. Tigris and Euphrates

Fed by rivers from mountains of Turkey, Iran, Afghanistan

2. Inland drainage systems like Dead Sea

3. Mangroves on coasts of Red Sea, Indian Ocean, Persian Gulf

F. Africa

1. East Africa and the Nile Basin

Great Rift Valley

Lake Victoria

Valley of the Nile

Sudd floodplain

2. West and Central Africa

Floodplains of the Senegal, Nile, Lake Chad; in arid Sahel

Zaire River system

Zaire and Congo Rivers; year-round flooding

3. Southern Africa

Zambesi River system

Okavanga Delta (N. of the Kalahari Desert)

Etosha Pan in Angola

G. Asia

1. Northern Asia

Ob-Irtysh basin

High mountains of N. Central Asia (Lake Baikal)

Tundra in the North

Internally drained seas: Caspian, Aral (eco-disaster)

2. Central and South Asia

Himalayan range dominates; generates water for:

Indus, Ganges, Brahmaputra, Irrawaddy, Mekong, Yangtze, Yellow Rivers

Extensive floodplain and delta cultures

Monsoon wetlands of Bangladesh (Ganges delta)

Sundarbans (mangroves, Bengal tigers)

3. East Asia

High altitude lake and bog systems, Tibetan and Mongolian plateaus

Yangtze and Yellow R. floodplains

Estuarine and mangrove systems on China coast

Korea: western and southern estuaries

Japan: most remaining wetlands on Hokkaido

H. Southeast Asia

1. Equatorial

Very wet, naturally forested, high diversity forests

Mangrove, swamp forest

2. Long coastline, shallow lagoons, coral reefs

I. Australia

1. Mostly flat and arid

2. Great Dividing Range along east coast

Generates much hydrology; monsoons approach from east

Well-watered river valleys and estuaries to the east

Darling and Murray floodplains to the interior

3. Ephemeral internally-drained systems in interior

Dry climate with widely spaced wet episodes

Salt lakes

4. Estuaries and floodplains in the tropical north

J. New Zealand and Pacific Islands

1. New Zealand: maritime climate and much rain

South Island has diverse wetland landscape

Bogs, floodplains, podocarp swamp forests

North Island has estuaries

2. Pacific islands

Mostly small islands with salt or brackish systems

Lagoons, mangroves, brackish lakes

Larger islands with mountains create river systems

Freshwater lakes form in volcanic calderas