Dunes, wetlands and mangroves are vanishing with the physical alteration of coastal regions. The changes include recreational development, harbour construction and aquaculture as well as the result of urbanization, sand mining, beach and sand dune erosion, or soil erosion from inland.
The destruction of wildlife habitats and fishing spawning grounds takes place not just through physical transformation of the coastline, of course. Landfills and sedimentation, chemical changes induced by pollution and biological alterations through introduction of non-indigenous species add to the the severe modification that has taken place on coasts around the world.
UN marine scientists warn: "Increasing habitat destruction and ecosystem alteration [...] constitutes the most widespread, frequently irreversible, human impact on the coastal zone."
Source: GESAMP (IMO/FAO/UNESCO-IOC/WMO/WHO/IAEA/UN/UNEP Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection). 2001. A sea of troubles. Rep. Stud. GESAMP No. 70, 35 pp. ISBN 82-7701-010-9.