Erosion occurs when small pieces of Earth shift their shape and move across landscapes, leaving behind incredible terrain features. Erosion is an inexorable natural process responsible for some of Earth’s most incredible landscapes.
Rain and wind cause erosion by transporting dirt from one place to the next – this process is known as mechanical weathering.
Water
Soil erosion is caused by water from rainfall, melting snow, rivers and glaciers; an unavoidable natural process made worse when people convert grassland or forest into agricultural fields.
Water erosion occurs when moving bodies of water erode rocks together or wear away at them over time, leading to the creation of gullies, crevices and canyons such as Namibia’s Fish River Canyon. Eroded material then falls into streams or rivers where it is then carried to sea or floodplains for disposal.
Raindrops can also erode soil by splashing as they fall, particularly on barren ground such as deserts. This type of erosion, known as splash erosion, detaches small particles from the surface and detaches them to travel long distances through suspension or surface creep or break apart by abrasion.
Wind
Erosion occurs when particles of soil, sand, silt, and clay move along a wind current and disperse into the environment by way of gusts of wind. Wind erosion typically takes place on unprotected bare ground surfaces in arid and semi-arid climates; its effect can be worsened by cropping techniques that crush surface aggregates as well as environmental factors like precipitation levels, dry months duration, the predominant wind direction, field size and vegetative cover.
As wind erodes, it dislodges soil particles from their original position on Earth and transports them either via suspension into air currents or rolling along its surface. Silt and clay-sized particles may travel great distances while smaller sand-sized particles travel shorter ones. When the wind stops blowing, sediment deposition takes place – either instantly with splash erosion from rainfall hitting earth surface directly, or over years in case of glaciers.
Waves
Waves constantly impact a coastline, wearing away material gradually over time. Waves can erode rock by striking it directly or carry particles of sand and soil from one spot to another before depositing them somewhere new (deposition). Wave erosion shapes coasts by creating beaches and spits along its route.
Refraction occurs when waves approach shallow waters, changing shape and losing energy through bending. More frequently refracting waves tend to erode shorelines more quickly.
Over time, waves can erode the base of cliffs to form sea caves – these hollow areas may collapse and form a seastack, though people have tried to slow this erosion through structures like groins and breakwaters built perpendicularly and parallel to beaches respectively; these structures serve to hold back erosion as they protect from the forceful waves.
Soil
Erosion can threaten soil quality, reduce crop yields and even lead to flooding. Eroded sediments can clog rivers and canals, decreasing water-holding capacity while washing away fertile topsoil. Erosion also pollutes freshwater ecosystems by entering streams.
Soil erosion occurs when bare dirt is exposed to wind, rain and waves; its effects become particularly visible during short duration storms with high intensity; raindrop splash and runoff water being among its prime culprits in erosion.
Erosion depends on the type of soil and its erodibility; fine, powdery soils tend to erode more readily than their coarser, granular counterparts, with wind carrying loose particles away from their source site (suspension), dislodging other loose materials or rocks and adhering them back onto surfaces (surface creep), as well as human activities like intensive agriculture, deforestation, roads construction or climate change contributing to faster rates. Erosion can also be hastened through human activities like intensive agriculture, deforestation roads construction or climate change among others – leading to acceleration of erosion rates as well as human activities like intensive agriculture, deforestation roads construction or human climate change contributing to faster erosion rates than natural soil erosion rates.