Rivers: Large natural streams of FRESH WATER formed by converging tributaries and which empty into a body of water (lake or ocean).Lakes: Inland bodies of still or slowly moving FRESH WATER or salt water, larger than a pond, and supplied by RIVERS and streams.Lactococcus lactis: A non-pathogenic species of LACTOCOCCUS found in DAIRY PRODUCTS and responsible for the souring of MILK and the production of LACTIC ACID.Fresh Water: Water containing no significant amounts of salts, such as water from RIVERS and LAKES.Great Lakes Region: The geographic area of the Great Lakes in general and when the specific state or states are not indicated. It usually includes Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, and Wisconsin.Kluyveromyces: An ascomycetous yeast of the fungal family Saccharomycetaceae, order SACCHAROMYCETALES.Ross River virus: A species of ALPHAVIRUS associated with epidemic EXANTHEMA and polyarthritis in Australia.Nisin: A 34-amino acid polypeptide antibiotic produced by Streptococcus lactis. It has been used as a food preservative in canned fruits and vegetables, and cheese.Water Microbiology: The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.Water Pollutants, Chemical: Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.Geologic Sediments: A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689)Water Movements: The flow of water in enviromental bodies of water such as rivers, oceans, water supplies, aquariums, etc. It includes currents, tides, and waves.Eutrophication: The enrichment of a terrestrial or aquatic ECOSYSTEM by the addition of nutrients, especially nitrogen and phosphorus, that results in a superabundant growth of plants, ALGAE, or other primary producers. It can be a natural process or result from human activity such as agriculture runoff or sewage pollution. In aquatic ecosystems, an increase in the algae population is termed an algal bloom.Ecosystem: A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Water Pollution: Contamination of bodies of water (such as LAKES; RIVERS; SEAS; and GROUNDWATER.)Phytoplankton: Free-floating minute organisms that are photosynthetic. The term is non-taxonomic and refers to a lifestyle (energy utilization and motility), rather than a particular type of organism. Most, but not all, are unicellular algae. Important groups include DIATOMS; DINOFLAGELLATES; CYANOBACTERIA; CHLOROPHYTA; HAPTOPHYTA; CRYPTOMONADS; and silicoflagellates.Cichlids: Common name for perch-like fish of the family Cichlidae, belonging to the suborder Labroidei, order PERCIFORMES.Fishes: A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.Environmental Monitoring: The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.