There are not many people that know how important wetland areas are and some may not know what wetlands even mean. Here are some definitions that enable you to understand about the wetland and how they are functionally important to social and the natural environment.
Wetlands are defined as areas where water covers the soil, or are present either at or near the surface of the soil all year or for varying periods of time during the year. Similarly, wetlands are also referred to lands transitional between terrestrial and aquatic ecosystems where the water table is usually at or near the surface or the land is covered by shallow water. According to Ramsar Convention, wetlands are 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 meters.
Wetlands vary widely because of regional and local differences in soils, topography, climate, hydrology, water chemistry, vegetation and other factors, including human disturbance. There are two general categories of wetlands which are recognized: coastal wetlands and inland wetlands.
Freshwater Wetlands in Streung Treng, Cambodia. (Photograph: Adam Oswell)
Wetlands play vital roles in both aquatic and terrestrial ecosystem such as varieties of water birds, fishes, reptiles, amphibians, mammals and so on. Moreever, wetlands are a critical part of our natural environment. They can protect shores from wave action, reduce the erosion, absorb pollutants and improve water quality and reduce the impacts of floods. They provide habitat for animals and plants and many contain a wide diversity of lives.
Wetlands are a critical part of our natural environment, and play a key role in supporting biological diversity such as waterbird, fish, amphibian, reptile and plant species during important life stages by providing roosting, nesting and feeding habitat as well as refuge during extreme weather conditions. They also form corridor or stepping stone habitats that support the migration of species, including waterbirds and marine mammals. It has been known that freshwater wetlands hold more than 40% of all the world’s species and 12% of all animal species.
Wetlands Water Birds in Prek Toal, Cambodia
The most significant wetlands provide is flood control. Peatlands and wet grasslands alongside river basins can act like sponges, absorbing rainfall and controlling its flow into streams and rivers. When peat becomes completely saturated and unable to absorb any more water, surface pools and peatland vegetation – including sedge meadows and some types of forest – help to slow and reduce runoff.
Shoreline and Storm Protection
Coastal wetlands such as reefs, mangroves and saltmarshes act as frontline defense against potential devastation. The roots of wetland plants bind the shoreline together, resisting erosion by wind and waves and providing a physical barrier that slows down storm surges and tidal waves, thereby reducing their height and destructive power.
Wetlands role as the natural filters, purifying water in a number of ways. For example, nitrogen in water is transformed to harmless nitrogen gas, nutrients are taken up by wetland plants in the water. Moreover, wetlands remove pollutants such as phosphorous, heavy metals and toxins which are trapped in the sediments of the wetlands. In addition, nitrogen and heavy metals are incorporated into peat during its formation.
Social Economical Value
Wetlands yield fuelwood for cooking, thatch for roofing, fibers for textiles and paper making, and timber for building. Medicines are extracted from their bark, leaves, and fruits, and they also provide tannins and dyes, used extensively in the treatment of leather. Besides, wetlands everywhere provide important leisure facilities - canoeing and fishing, shell collecting and bird watching, swimming and snorkeling, hunting and sailing.