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Antique Dutch windmills used to pump water into the embanked river to prevent waterlogging of the lowlands behind them. Waterlogging water is the saturation of soil with water. [1] Soil may be regarded as waterlogged when it is nearly saturated with water much of the time such that its air phase is restricted and anaerobic conditions prevail.
Underwater logs are safe from many of the forces which cause decomposition, including fungi. Log salvage operations began in the early 20th century across the United States. John Cayford and Ronald Scott's book Underwater Logging describes the process and prospects for retrieving sunken wood from American waterways, known as salvage logging .
Water then infiltrated the inside of the mound and by combining with tannin exuding from the tree trunks, set up acidic conditions which destroyed the skeleton but preserved the skin, hair, ligaments, and clothing of the individuals. Perhaps the most interesting wetland archaeological find was the Ozette site.
The longest natural period of a seiche is the period associated with the fundamental resonance for the body of water—corresponding to the longest standing wave. For a surface seiche in an enclosed rectangular body of water this can be estimated using Merian's formula: [ 6 ] [ 7 ]
Surface and ground water stagnation; Trapped water stagnation. The water may be trapped in human artifacts (discarded cans, plant pots, tires, dug-outs, roofs, etc.), as well as in natural containers, such as hollow tree trunks, leaf sheaths, etc. To avoid ground and surface water stagnation, the drainage of surface and subsoil is advised.
Lake Nyos, the site of a limnic eruption in 1986. A limnic eruption, also known as a lake overturn, is a very rare type of natural hazard in which dissolved carbon dioxide (CO 2) suddenly erupts from deep lake waters, forming a gas cloud capable of asphyxiating wildlife, livestock, and humans.
A natural disaster is the very harmful impact on a society or community after a natural hazard event. Some examples of natural hazard events include avalanches , droughts , earthquakes , floods , heat waves , landslides - including submarine landslides , tropical cyclones , volcanic activity and wildfires . [ 1 ]
A noticeable break in the pattern of the waves — the water often looks flat at the rip, in contrast to the lines of breaking waves on either side of the rip. A "river" of foam — the surface of the rip sometimes looks foamy, because the current is carrying foam from the surf out to open water.