A wetland is an ecosystem that is flooded by water and most of the processes occur without oxygen. Wetlands can be flooded either seasonally or permanently, and the water can be freshwater, saltwater, or brackish. A wetland is different from other water bodies primarily because of the type of aquatic plants that grow in the ecosystem, which are specifically adapted to the hydric soil in wetlands. Hydric soil is saturated by water, seasonally or permanently, thus creating an oxygen-free environment.
Where Are Wetlands Located?
Among all ecosystems in the world, wetlands are regarded as the most biologically diverse due to the wide range of flora and fauna they contain. These ecosystems exist naturally in all continents, and the main types include swamps, bogs, marshes, and fens. Sub-types of wetlands include mangrove forests, vernal pools, and floodplains. Some of the largest wetlands in the world include the West Siberian Plain (Russia), the Pantanal (Brazil, Bolivia and Paraguay) and the Amazon River basin (numerous countries in South America).
Why Is It important to Preserve Wetlands?
Wetlands act as natural water storage reserviors that prevents flooding. Since most floodplains form near the mouths of major rivers, they slow the velocity of the water and allow it to settle, thus preventing flooding. Examples of such floodplains include the Niger River inland delta and the Okavango River inland delta. If humans interfere with the natural course of rivers and drain floodplains, then the likelihood of flooding increases.
Wetlands also replenish the water in the ground since surface water and groundwater are directly linked. Aquifers are an example of underwater sources, which provide about 95% of the world's drinking water. In addition, wetlands can act as a discharge zone if there is too much underground water. Human activities, such as irrigation, also use groundwater. However, excessive water usage and growing water scarcity are now significant global concerns.
When wetlands along the coastline of large bodies of water, they serve as protection against violent tidal waves and storms. While these wetlands may not stop the storms, they can reduce their energy. However, as coastal areas become increasingly developed for human habitation, this protection becomes diminished. In addition, wetlands can be important tourist and recreation areas, and the loss of wetlands will have a negative impact on tourism.
Since wetlands cycle sediments and nutrients, they purify water naturally. Wetlands filter out nutrients for plant usage and produce clean water. These plants help in maintaining the rich biodiversity of wetlands. Unfortunately, human encroachment and interference have led to changes in the water levels, thus reducing the ability of wetlands to purify water. The plants that depend on this water and nutrients are also adversely affected.
Wetlands also act as a carbon sink that stores greenhouse gases and converts carbon dioxide into plant material through photosynthesis. Wetlands can also store and regulate water. For example, wetlands can store about 44.6 million tons of carbon annually. Accordingly, there are growing efforts from governments and individuals to improve the preservation of wetlands.