| Invasive species via ship ballast water transport has drawn extensive attention worldwide because they have damaged the marine ecosystems and economic development with the rapid growth of shipping industry.IMO(International Maritime Organization) passed "Intemational convention for the control of ships ballast water and sediments" in 2004 and this convention will be enforced from 2009.It is an urgent affair that how to deal with the ballast sediments for maritime management administrations and marine environment protection departments.To meet this requirement,this study,supported by National Key Technologies R&D Program(Project No.2006BAC11B04),has been carried out on sampling of ballast sediments,analyzing the basic properties of ballast sediments,and making preliminary morphological identification for the microalgae and cysts in it.Moreover,this study utilizes a microwave method to treat the ballast sediments based on the feasibility study of proposed alternative technologies.The results can be summarzied as below:1.Organisms in the samples make up of diatom and dinoflagellate cyst which gain the ascendancy over,and also have some harmful algae which distributed worldwide, some cysts of harmful algae such as Alexandrium spp.Then analyzing and find the species and densities of the microalgae and cysts in ballast sediments may be effected according to sea environment of voyage routes and voyage time.2.Not only has microwave method fatal damage to the cell wall and organelles but also the structure of cyst,which results in non-germinating of the cysts permanently.3.The result of cyst bourgeon experiment has explained the effect on cysts after microwave treatment,when the power is very large and the action time is very long,the cysts do not germinate permanently.This shows that microwave treatment impact has an relationship with microwave power and action time,compared with action time, microwave power has more contribution to treatment impact.
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