Mudflats and marshes
Intertidal marshland, including fish ponds, oyster pits and marshes, is particularly
vulnerable. The networks of channels favour the transportation of oil towards
very sheltered areas where low energy regimes and fine sediment retain them
for long periods of time. Oil quickly and severely affects the populations
of invertebrates living in the sediment, and the parts of plants in contact
with the water. Human intervention in this type of site can lead to risks
of disruption to the site and alteration of the ecological balance. Intervention
in these areas should be well planned and carried out carefully.
Marine marshes in temperate areas, like tropical mangroves, are particularly
sensitive to oil pollution. The respiration of the aerial roots of mangrove
trees can be seriously impaired by even a thin lens of oil. Furthermore,
numerous species live in these areas, some permanently, others on a seasonal
basis, for many at the juvenile stage, when they are particularly vulnerable.
Oiling of a mangrove swamp during the season when young prawns feed there
before heading out to sea can have serious consequences for coastal fishing
and the biodiversity of the surrounding environment for several months,
or even years.
Mudflat and traces of pollution on the embankment
Marshes polluted by the Prestige pollution