Although wetlands are generally defined as areas of land covered in water, wetlands are not always wet! Some wetlands are permanently flooded while others may only experience seasonal flooding. Some wetlands rarely flood but have continually saturated soils while others are completely dry for lengthy periods. So, what do they all have in common?
An area may be classified as a wetland if it has the following characteristics:
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The plants are mostly hydrophytes (plants adapted to growing in water saturated soils).
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The substrate is mostly undrained, hydric soil which has anaerobic or low-oxygen conditions due to water saturation.
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The substrate is covered by water at some point during the year.
Wetlands are some of the most productive ecosystems on the planet and are an integral part of the natural environment. They prevent erosion, reduce the impacts of flooding, absorb pollutants and improve water quality, and provide vital habitat for plants and animals including those which are not found anywhere else.
Urban wetlands are located within cities or towns and have the added environmental pressures of urban pollution such as rubbish, sewage, pesticide, oil and chemical run-off and spills.