wetland facts

The MedWet Wetland Facts give a brief introduction to the social and economic values of wetlands.

This section has been based on three MedWet publications namely, Mediterranean wetlands socioeconomic aspects (Benessaiah, 1998), Functions and values of Mediterranean wetlands (Skinner and Zalewski, 1995), Wetlands and Hydrology (Acreman, 2000), as well as on The Socio Economic Value of Wetlands  reproduced with kind permission by Wetlands International.

 To view the full contents of the report "Stuip M A M, Baker C J, Oosterberg W (2002) The Socio-economics of wetlands, Wetlands International and RIZA, The Netherlands" (upper left cover), click here (PDF, 34 pages with pictures, diagrams, available in English).

To order a copy of the book "Benessaiah N (1988) Mediterranean wetlands socioeconomic aspects, Ramsar Convention Bureau, Gland, Switzerland" (upper right cover, 165 pages with pictures, maps, diagrams available in English, French, Arabic) you can contact:

MedWet Coordination Unit

e-mail    

Tel: (+30) 210 80 89 270

For a copy of Acreman M (2000) Wetlands and hydrology, MedWet Station Biologique Tour du Valat Arles (110 pages with photographs, diagrams and tables, available in English and French) or Skinner J, Salewski S (1995) Functions et values of Mediterranean wetlands, MedWet Station Biologique Tour du Valat Arles (78 pages with photographs diagrams and tables available in English and French) you can contact:
Station Biologique de la Tour du Valat
e-mail

Tel (+33) 04 90 972013

What is a Wetland?

Wetlands are lands that hold water at least for part of the time. And while some wetlands may look like small lakes others may appear dry because the water is stored beneath the surface.

This ‘in between’ and dynamic character makes the plant and animal communities of wetlands unique and quite different to those of either aquatic or dry habitats.

The Ramsar Convention defines wetlands as:

"areas of marsh, fen, peatland or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six metres".

In addition there are human-made wetlands such as fish and shrimp ponds, farm ponds, irrigated agricultural land, salt pans, reservoirs, gravel pits, sewage farms, and canals.

Wetlands occur in every country, from the tundra to the tropics.

How much of the earth’s surface is presently composed of wetlands is not known exactly. The World Conservation Monitoring Centre has suggested that roughly 6% of the Earth’s land surface is made up of wetlands.

Lakes represent 2% of that while bogs make up 30%, fens 26%, swamps 20%, and floodplains 15%.

Why Should We Care About Wetlands?

Ever since civilisation began, wetlands have played a key role in the support and development of society. The fertile Nile and Tigris/Euphrates river valleys supported the ancient Egyptians and Babylonians. Entire cultures have developed based on the seasonal flooding of wetlands in the Sahelian zone of Africa where grazing
for cattle and fishing provide support to the diet of many African tribes.

The beneficial functions of wetlands for man are still evident today. The shallow waters of Lake Burullus, formed by the Egyptian Nile river as it flows into the Mediterranean Sea, offer ideal nursery grounds for fish. Protected  by a long sand bar from the cold waters of the open sea, the warm and shallow waters of the lagoon, rich in food, offer a shelter needed by young fish to grow into juveniles.

Sailing out into Lake Burullus in larger size boats called markeb or smaller size felloucas, local fishermen harvest its rich bounty, supporting tens  of thousands of fishermen.

In current times, wetlands are also capable of providing alternative sources of income for local people. Uses of wetlands have diversified into leisure pursuits such as recreational fishing, hunting, birdwatching and boating, which can generate money from visitors and provide sustainable development opportunities.

In addition, many additional services and benefits are provided by wetlands that are often less tangible. Water quality improvement, flood protection and provision of navigable waterways can all be provided by wetlands depending on their type and location.

For many people they also provide nature sanctuaries whether in terms of a landscape that may have historical or cultural significance or as reserve for biodiversity such as species-rich coral reefs. One can say that wetlands are important to people for a wide range of reasons from life-support to development to cultural inheritance.

However, continued provision depends on maintenance of the integrity and health of wetland resources; a major challenge in a world where pressure on resources is increasing due to a growing and developing population.

How Threatened Are Wetland Ecosystems?

The Ramsar Site Database provides insight into the main threats to wetlands. In 1999, 84%1 of Ramsar-listed wetlands had undergone or were threatened by ecological change. The most widespread threats are:

• Drainage for agriculture

• Settlements and urbanisation

• Pollution

• Hunting

Worldwide, 50%1 of wetlands are estimated to have been lost since 1900. During the first half of the previous century, this mostly occurred in the northern temperate zone.

However, since the 1950s, tropical and sub-tropical wetlands, particularly swamp forests and mangroves have also been rapidly disappearing.