Developed Coasts

Excerpt

The term “developed coast” often implies a natural system altered by human action. The type, frequency, and magnitude of alterations are influenced by the social and economic value humans place on the resource. Today, developed coasts are modified and physically maintained by humans to enhance navigation, recreation, and protection of settlements. Human modification of the coast has resulted in changes to the dimensions and locations of coastal landforms and the spatial and temporal scales of cycles of erosion and accretion. Globally, human presence on the coast dates back to tens or even hundreds of thousands of years, with some of the earliest documentation on the Mediterranean coast (Nordstrom, 2000). Deforestation and overgrazing were perhaps the earliest human actions that significantly altered the coast by increasing the quantity of sediment delivered (Walker, 1985). Grazing initiated dune migration when practiced directly on the coast. Channelization, diversion, and impoundment of water resources had the opposite effect on the coastal sediment budget; levees and dams decreased sediment delivery from river sources, with the most conspicuous effects occurring in the 20th century. …