Nitrogen stable isotopes and metal concentrations in marine macroalgae from brazilian regions with diferent levels of anthropogenic impacts - Shibuya, Elisa K; Oliveira, E. C; Yoshida, Letícia T; Ometto, Jean P H B; Martinelli, Luiz Antonio; Abreu, Cássio H; Soares, Lucy Satiko Hashimoto (Congresso Latinoamericano de Ciencias del Mar(COLACMAR) 13, Havana- Cuba, 2009)