This paper summarizes the improvment to “configurational limiting method”,draws into and redefinits the important concept of couple areas,special area,ideal special area,arris, validity arris and so on,makes the further extending,testing and verifing to the application of “Euler formula”.

On the basis of describing the condition of marine pollution of Bohai and analyzing the important influence of all substance discharged by ships on Bohai sea,the significance to designate Bohai Sea as a special area is discussed by comparing different discharging amounts between special and general sea areas under the convention of MARPOL 73/78.

These resources mostly exist in the form of special protection areas, such as natural reserves and scenic spots, etc.