eutrophication, salinity, nitrification, deglaciation, depletion, phytoplankton, hydrologic cycle, salination, sedimentation, cyanobacteria, alkalinity, pteropods, biota, nitrogen fixation, oxidation, biodiversity, sulphate, benthos, bleaching, overfishing, glaciers, diatom, sulfate, deoxygenation, ecosystems, sediments, plankton, desiccation, oxygenation, upwelling, volcanism, denitrification, biodegradation, carbonic acid, oxidization, recrystallization, metabolic acidosis, superoxide, anoxia, acrolein, overexploitation, moulins, degradation, hypoxia, calcification, benthic, calcium carbonate, oxidisation, reefs, soil erosion, silting, amphipods, corals, acidity, melting, icecaps, pteropod, peroxidation, desertification, isoprene, oxidants, hydroxyl radical, leaching, toxaphene, climate change, photosynthesis, biogeochemical, alkalosis, bile acid, gastropods, alga, toxicity, biofouling, winterkill, vasodilatation, organisms, amundsen sea, denudation, acid rain, hydrosphere, global warming, freshwater, phosphates, osmium, shoaling, azolla, nephron, volatilization, myoglobin, phenanthrene, echinoderm, gobies, seiche, glaciation, ciguatera, catabolism, soils, anabaena, suberin, purines, acidosis, meltwater, warming, dehydration, resorption, vasodilation, destabilization, erosion, alkalinization, denaturation, depolarization, retention, subsidence, vasoconstriction, dilation, distention, hydrolysis, sequestration

action, activity, natural action, natural process