Avaliação de risco para introdução de espécies exóticas e considerações sobre sistemas de tratamento de água de lastro

Abstract

The main proposal of this work is to create a mechanism capable of performing a categorization on the risk coefficient using the environmental similarity calculated through 2 parameters (salinity and water temperature) between Brazilian ports and other ports. Two instruments were used: the " Ballast Water Reporting Forms" and data obtained through the ANTAQ website in order to quantify or estimate the ballast discharged at our ports. Through the forms, it was possible to determine exclusively the origin of the ships (the last port visited), the number of ships that carried out the oceanic exchange, the foreign ports which most donated ballast water and the treatment systems installed on the ships. At the same time, we analyzed the data obtained from the ANTAQ site using the estimated discharged calculation method. As the number of forms was insufficient to characterize the influence of the deballasted volume, we used the estimated total discharged volumes for the years 2013 and 2016. These volumes had values around 160 million tons and 180 million tons, respectively. Through these, it was possible to identify and select three ports to carry out the risk assessment for the introduction of invasive species: Tubarão, Santos and Paranaguá ports. In addition to being ports that are among the 10 largest ports receiving ballast water, they were ports that presented environmental data provided by the GloBallast Program. The results analyzed were used for the risk classification, which is unique for each port studied. Despite the small number of forms, it was possible to verify the ballast water treatment systems installed in the ships that arrived in Brazil in 2013 and 2016. A great difference was observed in the information described in the forms received in those years in relation to the treatment systems. Most of the vessels (2016) have filtration as one of the processes, and this is accompanied by another process to improve the efficiency of the installed systems, being ultraviolet and electrolysis / electrochlorination the most used.