The coastal syndromes and hotspots on the coast.
Human intervention has resulted in a number of global and river syndromes that are mirrored by coastal syndromes caused by erosion, subsidence, salinization of aquifers, urbanization, eutrophication, invasive species and over exploitation of natural resources. These problems are now global, with few coastal zones remaining unaffected and pristine. However, the problems are particularly severe at "hotspots" in the coastal zone. These include river-mouth systems where fluxes of water, sediment, fertilizers and contaminants are focused; urbanized coasts and megacities where vulnerable populations are concentrated; Arctic coasts where the effects of climate change are accelerating a fundamental state change; and, at low lying coasts that are at risk of flooding, storm surges, sea-level rise and subsidence such as Micronesian island states where managed realignment and setback is not an option. A range of societal responses and appropriate governance frameworks will be necessary to treat the coastal syndromes.