Case study: Intertidal Wetlands
Intertidal wetlands:
- develop in coastal areas subject to periodic inundation by salty water
- mangrove wetlands occur in intertidal zones along tropical and subtropical coastlines, usually between 25oN and 25oS latitude.
- contain plants adapted to life in saline conditions for example, mangroves, seagrass.
- usually have large quantities of zooplankton and are thus safe areas for the smaller members of species
- are important for fishing industries (utility value), but also for biodiversity and intrinsic values.
- Coastal wetlands – in temperate areas (25 degrees N- 60 degrees N and 25 degrees S- 60 degrees S)
- Intertidal wetlands – in coastal areas of tropical regions, (specifically between 32oN-38oN)
- develop in coastal areas subject to periodic inundation by salty water
- mangrove wetlands occur in intertidal zones along tropical and subtropical coastlines, usually between 25oN and 25oS latitude.
- contain plants adapted to life in saline conditions for example, mangroves, seagrass.
- usually have large quantities of zooplankton and are thus safe areas for the smaller members of species
- are important for fishing industries (utility value), but also for biodiversity and intrinsic values.
- Coastal wetlands – in temperate areas (25 degrees N- 60 degrees N and 25 degrees S- 60 degrees S)
- Intertidal wetlands – in coastal areas of tropical regions, (specifically between 32oN-38oN)
Wetlands are areas where water is the primary factor controlling the environment and the associated plant and animal life. They occur where the water table is at or near the surface of the land, or where the land is covered by shallow water. Wetlands are defined 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".
As such the term “wetlands” extends to a wide variety of habitat types, including rivers and lakes, coastal lagoons, mangroves, peatlands, and even coral reefs.
Why conserve wetlands?
Wetlands are among the world’s most productive environments. They are cradles of biological diversity, providing the water and primary productivity upon which countless species of plants and animals depend for survival. They support high concentrations of birds, mammals, reptiles, amphibians, fish and invertebrate species. Of the 20,000 species of fish in the world, more than 40% live in fresh water. Wetlands are also important storehouses of plant genetic material. Rice, for example, which is a common wetland plant, is the staple diet of more than half of humanity.
More and more economists and other scientists are working in the field of the valuation of ecosystem services. This is a difficult task, still full of uncertainties, but there is no other choice than to progress in this direction. Some recent studies have indicated that ecosystems provide at least US$ 33 trillion worth of services annually, of which US$ 4.9 trillion are attributed to wetlands.
The interactions of physical, biological and chemical components of a wetland, such as soils, water, plants and animals, enable the wetland to perform many vital functions, for example: water storage; storm protection and flood mitigation; shoreline stabilization and erosion control; groundwater recharge (the movement of water from the wetland down into the underground aquifer); groundwater discharge (the movement of water upward to become surface water in a wetland); water purification through retention of nutrients, sediments, and pollutants; and stabilization of local climate conditions, particularly rainfall and temperature.
Wetland values
Wetlands provide tremendous economic benefits, for example: water supply (quantity and quality); fisheries (over two thirds of the world’s fish harvest is linked to the health of coastal and inland wetland areas); agriculture, through the maintenance of water tables and nutrient retention in floodplains; timber production; energy resources, such as peat and plant matter; wildlife resources; transport; and recreation and tourism opportunities.
In addition, wetlands have special attributes as part of the cultural heritage of humanity: they are related to religious and cosmological beliefs, constitute a source of aesthetic inspiration, provide wildlife sanctuaries, and form the basis of important local traditions.
These functions, values and attributes can only be maintained if the ecological processes of wetlands are allowed to continue functioning. Unfortunately, and in spite of important progress made in recent decades, wetlands continue to be among the world’s most threatened ecosystems, owing mainly to ongoing drainage, conversion, pollution, and over-exploitation of their resources.
"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".
As such the term “wetlands” extends to a wide variety of habitat types, including rivers and lakes, coastal lagoons, mangroves, peatlands, and even coral reefs.
Why conserve wetlands?
Wetlands are among the world’s most productive environments. They are cradles of biological diversity, providing the water and primary productivity upon which countless species of plants and animals depend for survival. They support high concentrations of birds, mammals, reptiles, amphibians, fish and invertebrate species. Of the 20,000 species of fish in the world, more than 40% live in fresh water. Wetlands are also important storehouses of plant genetic material. Rice, for example, which is a common wetland plant, is the staple diet of more than half of humanity.
More and more economists and other scientists are working in the field of the valuation of ecosystem services. This is a difficult task, still full of uncertainties, but there is no other choice than to progress in this direction. Some recent studies have indicated that ecosystems provide at least US$ 33 trillion worth of services annually, of which US$ 4.9 trillion are attributed to wetlands.
The interactions of physical, biological and chemical components of a wetland, such as soils, water, plants and animals, enable the wetland to perform many vital functions, for example: water storage; storm protection and flood mitigation; shoreline stabilization and erosion control; groundwater recharge (the movement of water from the wetland down into the underground aquifer); groundwater discharge (the movement of water upward to become surface water in a wetland); water purification through retention of nutrients, sediments, and pollutants; and stabilization of local climate conditions, particularly rainfall and temperature.
Wetland values
Wetlands provide tremendous economic benefits, for example: water supply (quantity and quality); fisheries (over two thirds of the world’s fish harvest is linked to the health of coastal and inland wetland areas); agriculture, through the maintenance of water tables and nutrient retention in floodplains; timber production; energy resources, such as peat and plant matter; wildlife resources; transport; and recreation and tourism opportunities.
In addition, wetlands have special attributes as part of the cultural heritage of humanity: they are related to religious and cosmological beliefs, constitute a source of aesthetic inspiration, provide wildlife sanctuaries, and form the basis of important local traditions.
These functions, values and attributes can only be maintained if the ecological processes of wetlands are allowed to continue functioning. Unfortunately, and in spite of important progress made in recent decades, wetlands continue to be among the world’s most threatened ecosystems, owing mainly to ongoing drainage, conversion, pollution, and over-exploitation of their resources.
Websites
Wetlands are important: Wetlands (mangroves, rivers, lakes and swamps) in Fiji contribute greatly to the... http://bit.ly/xd6cMT
