Interferences of elevated human pressure at marine coasts, and contaminants
transported by marine currents and rivers contribute to forced degradation of littoral
environments. Additional impairment has occurred due to inappropriate technical
constructions to protect built-up areas against floods caused by sea level rise. Delta
subsidence due to upriver damming, on and offshore hydrocarbon extraction, beach
sand mining, onshore ground water pumping, and soil compaction and loading because
of coastal urbanisation has resulted in accelerated sea level rise, marine ingressions,
and considerable land loss. Nutrient-rich runoffs, produced by intensified agriculture,
effected the origination of - partially temporary - hypoxic coastal water bodies.
Eutrophication and degradation of littoral waters also result from industrial
aquafarming. Harbour mud dredged for navigational purposes has been contaminated
with toxic metals. Oil and gas developments and havaries have caused severe
hydrocarbon pollution in littoral areas several times. Toxic legacies exist in the form of
waste-filled river and coastal impoundments, now exposed to sea level rise. Because of
the mobilisation of toxic leachates and submarine discharge of contaminated plumes
(e.g. in estuaries), redistribution of toxic metal species and their bioaccumulation
occurs. Saline brines, discharged from desalination plants in arid climate zones to
compensate for water scarcity, negatively impact water quality of ambient littoral
regions. Accidentally dispersed nuclear weapon material contaminated the inner shelf
area off Thule Airbase.
Keywords: Aquafarming, Coastal engineering, Coastal urbanisation,
Contamination, Delta subsidence, Desalination plants, Erosion, Estuaries,
Eutrophication, Flooding, Harbour mud, Hypoxia, Littoral, Marine ingression, Oil
spills, Pollution, Sand mining, Sea level rise, Tailings, Waste, Wetlands.
