A beach is a narrow strip of land, often made of sand, that lies along the edge of an ocean, lake or river. The sandy land is formed as wind and waves break up rocks and other material, crushing it into tiny sand grains. Beaches are always changing as they collect and lose materials. They can have many different characteristics depending on the type of sediment they contain and the nature of nearby marine and dune vegetation.
Beaches are very popular places for recreation and play a significant role in the economy of coastal communities around the world. They are also important natural habitats for plants and animals. Beaches protect nearshore land by dissipating the energy of waves that might otherwise impact underlying coastal terrain. Beaches are very dynamic, with constant changes in their size and shape on timescales of weeks or even days during major storms.
Some beaches are characterized by characteristic sand ridges called cheniers, which can extend for tens of kilometers. They are typically formed where currents pushing toward the coast meet currents pushing offshore, creating a zone of sand accumulation. Most beaches in the northern hemisphere, for example, are made of terrigenous, or siliceous, sand consisting primarily of quartz. Other beaches, especially in the tropics, are covered by biogenic, or organic, sands consisting of the skeletal fragments of shells and the remains of other marine organisms.
The main mechanism by which beaches change is erosion by waves, but the composition of a beach can be influenced by other factors. For instance, the nature of the surrounding marine and dune vegetation can have a strong influence on whether sand from a particular location is added to a beach.
A beach’s shape can be modified by dune-building plants and human activity. These activities may include building homes, roads and parking lots on sand dunes, as well as recreational activities such as swimming, sunbathing, boating and fishing. Beaches can also be affected by climate change, sea level rise and pollution.
A beach is a narrow, gently sloping strip of land that borders a body of water. The beach is usually made of sand, but can also be composed of other granular materials such as gravel, cobbles and shingle. Most beaches are found adjacent to oceans, but they can also be located by lakes and along rivers. Beaches are very popular recreational areas, and as such have many facilities such as lifeguards, changing rooms, showers, shacks and food vendors. The quality of a beach can be significantly reduced by human activities, such as littering and improper construction. Some beach management practices are intended to minimize these impacts and preserve and enhance the natural features of a beach.