Ballast water management convention , USCG Ballast water Discharge standard

( Phytoplanktons = Tiny plants )
(Zooplankton =Tiny animals )
Why do we need to control our ballast water.
History of Ballast water and the threats it poses to the environment.
Changes in shipping patterns causes a shift in trading intensity.
Opening up new areas could lead to a spread of a potential new species.