documentclass[a4paper]{article}
usepackage[top=2cm,bottom=2cm,left=2cm,right=2cm]{geometry}
usepackage[brazilian]{babel}
usepackage{qtree}

begin{document}

begin{figure}[!htb]
caption{{'{A}rvore de Instala{c{c}}{~{o}}es} Portu{'{a}}rias.}

begin{minipage}{0.5linewidth}
Tree [.{textbf{Sistema Portu{'{a}}rio} \ Lei 12.815/2013 \ Decreto 8.033}
        [.{Instala{c{c}}{~{o}}es} [.Organizado {Porto P{'{u}}blico \ de Pequeno Porte} {Esta{c{c}}{~{a}}o \ de Transbordo}  ] [.Privado [.{textbf{Registro} \ Resolu{c{c}}{~{a}}a Normativa n. 13}  {IP4\DNIT}
{ETC\ Petrobr{'{a}}s} ] ] ]
        [.{Regula{c{c}}{~{a}}o} Concess{~{a}}o Arrendamento Autoriza{c{c}}{~{a}}o Delega{c{c}}{~{a}}o ] ]

end{minipage}

end{figure}

end{document}