A beach is a strip of land bordering a body of water like an ocean, lake or river. It’s made up of sand, gravel and sometimes shells. Normally it slopes gently toward the body of water. Beaches change over time as they are continually washed and eroded by waves and deposited by tides. They also may be nourished artificially, such as with beach nourishment, in which sand is pumped onto beaches to prevent erosion.
The sand in most beaches is comprised of quartz, feldspar and other light minerals. In the tropics, however, some beaches are covered with sand that’s rich in calcium carbonate from the skeletons of tiny marine organisms, such as oysters and corals. Beaches are often lined with grass or other vegetation. They can also contain rocks, seaweed and driftwood.
A person who surfs, windsurfs, swims, surfboards or plays volleyball on a beach is called a surfer. Beaches are popular recreational areas and play important economic and social roles in many communities. Beaches also serve as natural habitats for wildlife, such as birds, insects and fish.
Most beaches are formed by erosion. Over time, the constant action of waves wears away at rocky coastlines and sand dunes. Huge boulders can be worn down to sand particles by wave pounding. In places where the rocks are too large to be moved by the waves, a beach can form as a result of wave erosion and dune forming.
Other forms of beaches are lagoons, sandbars and reefs. In some tropical oceans, algae grow on the ocean floor to form reefs, while other types of seaweed form sand bars and lagoons. During high-energy wave conditions, sandbars may form crescentic shapes on the beach.
In addition, a beach can be made up of different types of sediments. For example, sand in temperate regions is usually composed of quartz. Beaches in the tropics, on the other hand, have sand that’s rich in calcium, resulting from the skeletons of marine organisms and the breakdown of small pieces of shells.
Beach pollution occurs when humans pollute a beach with trash, such as paper, plastics, metals and other materials. The trash can harm wildlife, such as birds, that eat the debris or get caught in it and die. It can also cause injuries to swimmers and surfers and damage the quality of the beach’s water. In some cases, beach pollutants may even threaten human lives. Beach pollution can be a serious problem in countries with developing economies, where poorer citizens are more likely to visit the beach for recreation. Beach pollution is also a problem in wealthy countries with developed economies, where tourists contribute to beach-related waste. In the United States, for example, tourist visits to beaches have doubled in the past 20 years. To reduce beach pollution, local governments have begun to require trash recycling at beaches. In some cases, they have begun to ban smoking on beaches. In other cases, they have worked with environmental groups to establish parks that are free of smoking and other types of pollution.