Marine life asexually by binary fission, fragmentation, or budding; unlike bacteria and eukaryotes, no known species forms spores. Archaea are particularly numerous in the oceans, and the archaea in plankton may be one of the most abundant groups of organisms on the planet. Archaea are a major part of Earth's life and may play roles in both the carbon cycle and the nitrogen cycle. Of eukaryotic groups, the protists are most commonly unicellular and microscopic. This is a highly diverse group of organisms that are not easy to classify. Several algae species are multicellular protists, and there are marine slime molds have
Harmful Algal Bloom and Hypoxia Research and Control Amendments Act of 2013 accumulation in the population of algae (typically microscopic) in an aquatic system. Algal blooms may occur in freshwater as well as marine environments. Freshwater algal blooms are the result of an excess of nutrients, particularly some phosphates. Harmful algal blooms are algal bloom events involving toxic or otherwise harmful phytoplankton such as dinoflagellates of the genus "Alexandrium" and "Karenia" or diatoms of the genus "Pseudo-nitzschia". is an algal bloom that causes negative impacts to other organisms via production of natural toxins, mechanical damage to other organisms, or by other means. HABs are often associated with large-scale marine mortality events and