The most powerful. erosive force on earth is water which causes erosion in its solid form and as. a liquid. Water in its liquid form causes erosion in many ways.
Floods – Large floods can cause erosion to happen very quickly acting like powerful rivers.
There are two types of erosion: intrinsic and extrinsic.
The most important agent in both weathering and erosion is water, in both its liquid and solid states.
Running water is the leading cause of soil erosion, because water is abundant and has a lot of power. Wind is also a leading cause of soil erosion because wind can pick up soil and blow it far away. Activities that remove vegetation, disturb the ground, or allow the ground to dry are activities that increase erosion.
Agriculture is one of the leading contributors to erosion. When farmers remove natural vegetation to create farmland, it weakens the natural system of plants keeping the soil in place. This allows wind and water to carry away topsoil, sending it into nearby streams and rivers.
The time needed to form a soil depends on the latitude: in environments characterized by a mild climate, it takes 200-400 years to form 1 cm of soil. in wet tropical areas soil formation is faster, as it takes 200 years. in order to accumulate enough substances to make a soil fertile it takes 3000 years.
Three types of water erosion can occur, sheet, rill, and gully. Sheet erosion: This erosion is the hardest to see, as a uniform soil layer is removed from an area over the surface.
Ice– the MOST POWERFUL agent of erosion on Earth. The action of moving ice (by gravity) can move large chunks of rock. It is the fastest agent of erosion.
Surface creep is the slow downhill movement of soil and rock debris. It is usually not perceptible except through extended observation. The term can also describe the rolling of soil particles by wind along soil surface.
Like flowing water, flowing ice erodes the land and deposits the material elsewhere. Glaciers cause erosion in two main ways: plucking and abrasion. Plucking is the process by which rocks and other sediments are picked up by a glacier. They freeze to the bottom of the glacier and are carried away by the flowing ice.
Wind is a stronger erosional force in arid regions than it is in humid regions because winds are stronger. In humid areas, water and vegetation bind the soil so it is harder to pick up. In arid regions, small particles are selectively picked up and transported.
Water is the most important agent of chemical weathering. Two other important agents of chemical weathering are carbon dioxide and oxygen.
Gravity can cause erosion and deposition. Gravity makes water and ice move. It also causes rock, soil, snow, or other material to move downhill in a process called mass movement. Particles in a steep sand pile move downhill.
Weathering is a natural process, but human activities can speed it up. For example, certain kinds of air pollution increase the rate of weathering. Burning coal, natural gas, and petroleum releases chemicals such as nitrogen oxide and sulfur dioxide into the atmosphere.
Water – Water is the leading cause of erosion. When a temporary thaw or warmer weather returns, snow and ice turn to water that can cause soil loss due to melt runoff. Unprotected soil can break down, compromising landscapes, lawns and gardens susceptible to further damage.
Water erosion is the detachment and removal of soil material by water. The process may be natural or accelerated by human activity. … Water erosion wears away the earth’s surface. Sheet erosion is the more-or-less uniform removal of soil from the surface.
An often asked question is, “How long does it take to form an inch of topsoil?” This question has many different answers but most soil scientists agree that it takes at least 100 years and it varies depending on climate, vegetation, and other factors.
They are capable of very rapid reproduction by binary fission (dividing into two) in favourable conditions. One bacterium is capable of producing 16 million more in just 24 hours. Most soil bacteria live close to plant roots and are often referred to as rhizobacteria.
According to eniscuola.net, the time needed to form a soil depends on the latitude: – in environments characterized by a mild climate, it takes 200-400 years to form 1 cm of soil – in wet tropical areas soil formation is faster, as it takes 200 years …..
River Erosion – The Changing Shape of Rivers