A beach is a strip of sandy or rocky land that borders a body of water. It is the result of years of weathering and erosion. Over time, waves constantly beat a rocky shore, causing some rocks to come loose and to be worn down to tiny grains of sand. These sand grains are carried by winds to form beaches where the tide is low.
A beach usually slopes gently toward the water, although it can be flat or steep. It may be backed by dunes or cliffs and bordered by buildings or structures like seawalls. Most beaches are covered by sand and other ocean sediment, but they can also contain shells, algae, marine debris, and even dead animals. Beaches are not restricted to bodies of water, but they can occur anywhere on the planet where there is a coastline and a low tide.
During the interwar years, Americans looked to beaches as refreshing retreats where “living the simple life” enabled introspection and revitalization. Many of the beach resorts that sprang up in this period offered middle-class people a respite from the pressures and anxieties of everyday life. Inexpensive mass transit systems linked urban working-class neighborhoods to nearby shorelines, and automobiles made it possible for suburban and rural residents to make day trips or longer vacations to the beach.
The beach is the dynamic environment where land, sea, and air meet. It consists of unconsolidated sand, gravel, shells, and other materials that extend from the low water line to the point where there is a significant change in topography or material (such as a dune or a cliff).
Most beaches are composed of quartz sand, but they can also be comprised of coral fragments or carbonate skeletal fragments, or even marine organisms such as crabs and sea anemones. In addition to sand and shells, a beach can also include kelp and other forms of seaweed, which are often rich in nutrients.
A beach usually contains a high concentration of organic matter, which can make it especially sensitive to pollution and other environmental hazards. For example, beaches can become degraded by the introduction of pollutants that are picked up by wind or waves and carried a long distance from their source. Beach degradation is also caused by human activities such as building homes and roads near bodies of water, rerouting rivers, and clearing forested land.
Beach recession is the natural process by which beaches disappear and reappear as sediment is continually transported from one place to another. However, human activities can speed up beach recession by limiting the amount of erodible material found near bodies of water. In addition, beach recession can be the result of dam construction, urban development, and the rechanneling of rivers. Beach recession also occurs when large amounts of sand are removed from coastal areas for use in other projects such as golf courses and construction fill. This removal of sand results in a loss of beach habitat, which can also affect the ecology of adjoining landforms and ocean life.