Marine microorganism Marine microorganism Marine microorganisms are defined by their habitat as the microorganisms living in a marine environment, that is, in the saltwater of a sea or ocean or the brackish water of a coastal estuary. A microorganism (or microbe) is any microscopic living organism, that is, any life form too small for the naked human eye to see, needing a microscope. Microorganisms are very diverse. They can be single-celled or multicellular and include all bacteria and archaea and most protozoa, as well as some species of fungi, algae, and certain microscopic animals, such as rotifers. Many macroscopic animals and plants
Marine ecosystem living organisms. Combined with the sea floor (or benthic zone), these two areas have yet to be fully explored and have their organisms documented. In addition to providing many benefits to the natural world, marine ecosystems also provide social, economic, and biological ecosystem services to humans. Pelagic marine systems regulate the global climate, contribute to the water cycle, maintain biodiversity, provide food and energy resources, and create opportunities for recreation and tourism. Economically, marine systems support billions of dollars worth of capture fisheries, aquaculture, offshore oil and gas, and trade and shipping. Ecosystem services fall into multiple categories, including supporting