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This is a list of places on land below mean sea level. Places artificially created such as tunnels, mines, basements, and dug holes, or places under water, or existing temporarily as a result of ebbing of sea tide etc., are not included.
The Pantanal is a natural region encompassing the world's largest tropical wetland area. It is located mostly within the Brazilian state of Mato Grosso do Sul, but it extends into Mato Grosso and portions of Bolivia and Paraguay. It sprawls over an area estimated at between 140,000 and 195,000 square kilometres (54,000 and 75,000 sq mi).
The arid areas of the world are requiring more and more water for growing populations and agriculture. In the San Joaquin Valley of the United States, groundwater pumping for crops has gone on for generations. This has resulted in the entire valley sinking an extraordinary amount, as shown in the figure. [4] This has not come without consequences.
A simplified definition of wetland is "an area of land that is usually saturated with water". [14] More precisely, wetlands are areas where "water covers the soil, or is present either at or near the surface of the soil all year or for varying periods of time during the year, including during the growing season". [15]
The water table may vary due to seasonal changes such as precipitation and evapotranspiration.In undeveloped regions with permeable soils that receive sufficient amounts of precipitation, the water table typically slopes toward rivers that act to drain the groundwater away and release the pressure in the aquifer.
The Low Elevation Coastal Zone (LECZ) refers to low-lying coastal areas with an elevation below a certain threshold, commonly 10 meters, above mean sea level.Globally, there is a substantial and growing population living in the Low Elevation Coastal Zone, which consists of approximately 2% of the world's land area and around 11% of the global population.
In adopting this definition in 1985, Congress attempted to capture the duration of waterlogged condition of a hydric soil by adding that a hydric soil is waterlogged long enough to support not only the growth of plants adapted to life in anaerobic conditions but also the regeneration of such plants.
Eventually, peat builds up to a level where the land surface is too flat for ground or surface water to reach the center of the wetland. This part, therefore, becomes wholly rain-fed (ombrotrophic), and the resulting acidic conditions allow the development of bog (even if the substrate is non-acidic).