Hypoxia (environmental): Difference between revisions

'''Oxygen depletion''' is a phenomenon that occurs in aquatic environments as [[oxygen|dissolved oxygen]] ('''DO'''; molecular oxygen dissolved in the water) becomes reduced in concentration to a point where it becomes detrimental to aquatic organisms living in the system. Dissolved oxygen is typically expressed as a percentage of the oxygen that would dissolve in the water at the prevailing temperature and salinity (both of which affect the solubility of oxygen in water; see [[oxygen saturation]] and [[underwater]]). An aquatic system lacking dissolved oxygen (0% saturation) is termed anaerobic, [[Reducing environment|reducing]], or '''[[Anoxic waters|anoxic]]'''; a system with low concentration—in the range between 1 and 30% saturation—is called '''hypoxic''' or '''dysoxic'''. Most fish cannot live below 30% saturation since they rely on both nutrients and oxygen forto their chemicalderive energy.<ref name="Schmidt-Rohrfrom 20">their Schmidt-Rohr, Knutrients. (2020). "Oxygen Is the High-Energy Molecule Powering Complex Multicellular Life: Fundamental Corrections to Traditional Bioenergetics". ''ACS Omega'' '''5''': 2221-2233. http://dx.doi.org/10.1021/acsomega.9b03352. </ref> Hypoxia leads to impaired reproduction of remaining fish via [[endocrine disruptor|endocrine disruption]].<ref>Wu, R. et al. 2003. [https://www.researchgate.net/publication/231277909_Aquatic_Hypoxia_Is_an_Endocrine_Disruptor_and_Impairs_Fish_Reproduction Aquatic Hypoxia Is an Endocrine Disruptor and Impairs Fish Reproduction]</ref> A "healthy" aquatic environment should seldom experience less than 80% saturation. The '''exaerobic''' zone is found at the boundary of anoxic and hypoxic zones.