Related by context. Frequent words. (Click for all words.) 52 contaminate drinking 51 naturally occurring bacteria 51 ocean acidity 50 dissolved oxygen 49 Vibrio 48 saltwater intrusion 48 nutrient runoff 48 dissolved oxygen levels 48 bacteria 47 aquatic organisms 46 plankton 45 microbe 44 microbes 44 absorbing carbon dioxide 44 acidification 44 organisms 44 microorganisms 44 zooplankton 44 ammonia 44 protozoa 44 oxygen depletion 44 carbonic acid 44 marine organisms 44 harmful pathogens 44 seagrasses 44 phytoplankton 44 contaminate groundwater 44 bacteria viruses 43 algae blooms 43 aquatic ecosystems 43 hydrogen sulfide 43 algal 43 coli 43 toxicants 43 oxygen 43 Zebra mussels 43 clog arteries 43 freshwater 43 nutrients 43 salinity 43 filter feeders 43 toxic byproducts 43 microscopic algae 43 dehydrates 43 bacterial 42 toxic algae 42 harmful bacteria 42 sediment 42 aquatic weeds 42 contaminating 42 nutrient pollution 42 toxin 42 oxygen starved 42 polluted runoff 42 aquatic ecosystem 42 arsenic 41 Raw sewage 41 contaminants 41 toxins 41 algal blooms 41 odorless colorless gas 41 aquatic vegetation 41 fungal spores 41 nitrogen fixation 41 absorb nutrients 41 aquatic habitat 41 diatom 41 saltwater 41 copepods 41 sulfate 41 organism 41 hydrological cycle 41 Toxic chemicals 41 Didymo 41 microscopic organisms 41 E. coli salmonella 41 microorganism 41 anaerobic bacteria 41 intestinal bacteria 41 methyl mercury 41 hormone cortisol 41 Bacteria 41 nitrite 41 bacterium 41 micro organisms 41 eutrophication 41 anoxic 41 freshwater mussels 41 nitric oxide NO 41 diatoms 41 algae 40 freshwater ecosystems 40 gastric acid 40 acidified 40 pathogens 40 ocean ecosystems 40 E. coli bacteria 40 harmful contaminants 40 roundworms 40 Weddell Sea 40 underwater grasses