Microbial remediation of pollution in tropical coastal environments

The impact of waste on the coastal environment from urban sources and the agriculture, manufacturing and aquaculture industries can be mitigated by the use of appropriate microbes either individually or in consortia with plants. Aquaculture-coastal land-based and estuarine or bay cage aquaculture-and urban sewage and industrial organic wastes are particularly amenable to microbial technologies. Several criteria must be applied to ensure success. Appropriate species for microbial technology, i.e. microbes that are natural to, or integrate easily into, the natural ecological communities and provide the desired beneficial actions, have to be selected and produced at a cost that is acceptable to the end users. The microbes have to be added at a high enough population density to compete with the natural flora in the treatment sites. Bacteria that carry genes for antibiotic resistance and disease virulence must not be used in sites where they could affect not only human, but also fish and shrimp health; safety checks must be made during selection and production processes. Microbial technologies are now being used widely in the field of aquaculture, where an obvious cost-benefit is seen at harvest. Microbial technologies can lower energy and other costs of treating of urban and industrial wastes and assist in meeting regulatory targets for effluent quality.