Antifouling paints and fouling at Rovinj
Abstract
The smallest fouling on antifouling paint for ferro is in the cleaner waters, and average covering value is from 0 - 37%, extremely 76% (10 months of exposition). In the port on the same paint covering is significantly bigger, from 79 - 96%, and after 2 months of exposition only, it was 18%. From 8 months of exposition (cleaner sea) and from 6 months (port with urban pollution) the barnacles settle, more species Balanus amphitrite than B. eburneus. On paint were abundantly juvenile and preadult barnacles. Settlement these organisms and their sizes are the criterion that the paint on considerable begins to weaken from 6 and 8 months. The species Pomatoceros triqueter and Hydroidea attach especially on corners of test panels, and supposes that paint is more considerable weakining on these places.
The anticorrosion paint in the port is not toxic at all, as the fouling is very intensive all over the year (from 79 - 100%). In the cleaner sea the average covering values are bigger (65 - 99%) just after 6 months of exposition.
The antifouling paint for wood is better in quality than the protective paint for ferro, because dominant Slime film and higher algae (most resistant foulers). In the port the average covering values are from 15 - 60% (sometimes 86% - 4 months of exposition).
In Valdibora's by the test panels were exposed only for a month, had the covering rate from 0.10 - 12%, while test panels exposed for 2 to 9 months were fouled from 12 - 70%.
Unprotected wooden panels, in the port, are fouled from 71 -100% and only 18% after 2 months of exposition.
In function of time we cannot find the correlation between the lent of exposition and the intensity of fouling especially in the port. For example, after 12 months the fouling is lesser in the port and at the island Asino, because of the higher mortality of the foulers (especially barnacles). Otherwise, the toxicity of paint is successively weakening in Valdibora’s bay, except after 6 or 7 months was the bigger »invasion« of Nematoda.
Among all foulers the most resistant ones are unicellular organisms (Diatomeae, Cyanophyta, Vorticella patelina) higher algae, especially Chlorophyta, which fouled from 0.10 to 65% all test panels. These foulers about resistant follow barnacles, more Balanus amphitrite smaller B. eburneus, while the species Pomatoceros triqueter and Spirorbis sp. are also attaching on antifouling paints, but not so often and in smaller quantities. On antifouling paint for ferro in the port yet settles species Mytilus galloprovincialis also non considerable (abundance degree 2-3). The most delicate foulers on toxins are Porifera, errant Polychaeta, Bryozoa, and Tunicata. The colonies of Shizoporella sp. (Bryozoa) and of Diplosoma listerianum (Tunicata) on antifouling paint settle except as epibionts over Slime film and barnacles.
