[Coral-List] Impact of tyres degradation in coral reefs and lagoons

[Bernard-Armand THOMASSIN]

Dear colleagues,

With the development of the population and the car and truck parks in the small Mayotte Islands (Comoro Archip., 376 square-km), we have today hundred and hundred tyres sedimented on the islands shores, upon mud flats and coral patches, and also on the corals of the adjacent barrier reefs. 
A recent program studied these large wastes. Low altitudonal aerial observations in ULM underestimate the tyres density by 7 times less that collects on the intertidal flats of the Main Island
After tide floodings or heavy rainfalls, we observed that tyres are carried, floating vertically, by the surface currents washing the lagoon. So, they can be carried on quite important distances (several kilometers) and then they are stopped by the shallower coral patches of the inner barrier slopes or in large passages, inducing degradations of the coral colonies (breaking the more fragilous) and probably, alteration of the surrounding seawaters..

UV radiations seem to have very low action upon their degradation. Mechanical scrapping by waves seems to play more.
However, tyres in several indopacific countries are used to built artificial reefs to attract fishes.

So, we try to get informations on the impacts of this type of wastes, and upon the degradation speed of these tyres, with emission of pollutants in the waters (as sulphres and zinc, as mentionned by some authors, as COLLINS) and to the impacts that they create in these environments. 

Can you point out for me places where the tyres impact on coral reefs and lagoonal environments were important problems?
Please, send me references of papers or technical reports dealing with this subsjects.
With my thanks.

Bernard

Bernard A. THOMASSIN
Marseilles Oceanographic Center / Mediterranean Univ.
&G.I.S. "Lag-May" Scientific interest Consortium "Marine and littoral environments of Mayotte"tél GSM (33) 06 63 14 91 78
ba.thomassin at wanadoo.fr
Saisissez votre signature iciBernard A. THOMASSIN G.I.S. "Lag-May"tél GSM 06 63 14 91 78