Erosion is the process of gradually wearing away rock, soil and other material through erosion. This may occur naturally or be brought about through human intervention.
Water, wind, ice and gravity all play a role in erosion. Examples of such processes include boulders turning to sand over time and rivers carrying sediment to the ocean.
Water
Erosion occurs when water erodes rock particles from their surroundings, carrying soil particles with it as well as disintegrating any rocks it comes in contact with – this process is known as mechanical weathering. Gravity can also contribute to erosion by forcing rocks and soil down slopes into streams or rivers.
Erosion caused by water can result in flooding. Last year’s heavy rainfall in Jakarta caused its rivers and canals to overflow due to sediment clogging the water bodies due to erosion by water. Erosion can also lower crop yields as its top fertile layer of soil is destroyed.
Streams and rivers carry sediment from mountainous areas where erosion is rapid. When they reach flatter land, however, they slow down and start depositing their load of material – the largest particles first. Over time this deposits sediment into riverbeds, floodplains, deltas or even meanders which are seen globally.
Wind
Wind erosion can have devastating repercussions for natural ecosystems. It strips essential nutrients out of soil, leaving exposed rock exposed to rainwater and other environmental elements.
Water and wind erosion are primary culprits, but other forces can contribute to its progress as well. Glaciers scour away at land as they travel across it, picking up rocks and minerals along their route before depositing them in rivers and lakes; raindrops or torrential flooding also erode land, while snowmelt can have a destructive impact.
Wind erosion is most often seen in arid regions where rough, dry sediments are light enough for wind currents to carry away. Surface creep wind erosion can move large particles across the ground causing abrasion and attrition while transporting them over great distances. Wind erosion also shapes canyon walls into ventifacts formed over years by strong gusts of wind blowing across flat terrains.
Ice
Weight of Ice is responsible for erosion. Glaciers erode rocks through two processes – abrasion and plucking. Abrasion occurs when rock particles or pebbles incorporated in the glacier rub against its surface as it moves down a mountain valley, leaving behind scratches known as striations and grooves on the rock surface as it goes. Furthermore, this process produces glacial polish and smooths valleys over time.
Glaciers may deposit sediment onto the ground when they thaw, and when it falls onto rock surfaces it can compact and erode them, as well as altering their chemical makeup by reacting with other atoms or molecules – this process is known as weathering; weathering makes rock rough and slippery as it changes chemical makeup by reacting with other molecules; additionally it may change their colors from light or darker depending on whether sunlight penetrates through or not – all processes that continuously shape our planet but typically occur gradually over time.
Human Activity
Erosion refers to any process which wears away and modifies landforms on Earth, including weathering, transport and deposition. While typically associated with wind or water erosion, its wide definition also encompasses sediment transport and chemical weathering processes.
Water erosion is a natural process that shapes landscapes. Rainfall erodes land when flowing fast, picking up fine sand that washes away with its flow and carrying it off with it. Water movement may also cause chemical erosion by dissolving rocks and minerals into solution or dissolving them entirely, creating caves.
Agriculture is one of the primary human activities responsible for erosion, as it destroys vegetation and accelerates soil loss. Plowing fields, overgrazing livestock and other agricultural practices disrupt roots that stabilize the soil to accelerate erosion. As a result, reduced topsoil is available for crops as nutrients; increasing pollution in rivers and streams; as well as an increase in stormwater containing sediments carrying pollutants into oceans.