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Related to euphotic: photic, Photic zone


Of, relating to, or being the uppermost layer of a body of water that receives sufficient light for photosynthesis and the growth of green plants.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(juːˈfəʊtɪk; -ˈfɒt-)
(Environmental Science) ecology denoting or relating to the uppermost part of a sea or lake down to about 100 metres depth, which receives enough light to enable photosynthesis to take place
[C20: from eu- + photic]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(yuˈfoʊ tɪk)
of or pertaining to the zone of a body of water extending from the surface to a depth at which enough light still penetrates for photosynthesis to occur.
[1905–10; eu- + photic]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
These increases in phytoplankton are promoted by the interaction between physical forcing (e.g., wind and currents) and the topography of the island, promoting the injection of macro and micronutrients into the euphotic zone and stimulating biological production.
Cyanophytes also exploit nutrients at the bottom of the euphotic zone by buoyancy regulation of its gas vacuoles (Reynolds 1984b).
"Theories" and techniques for observing turbulence in the oceanic euphotic zone.
Also known as Island Mass Effect (Doty & Ogury, 1956), the increase of local Chl-a in the vicinity of these islands results from the increase of nutrients in the euphotic zone from the interaction between mesoscale eddies and island topography (Andrade et al., 2012, 2014).
A large percentage of oceanic zooplankton are transparent, some achieving almost complete invisibility (Davis, 1955; Hardy, 1956; McFallNgai, 1990), and it is generally assumed that transparency is an important method of camouflage from visual predators and prey in the optically featureless open-ocean environment, particularly in the euphotic region (reviewed in McFall-Ngai, 1990; Hamner, 1996).
Associated to northern Chile upwelling system, a shallow oxygen minimum layer (<0.5 mL [L.sup.-1]) within the euphotic zone might impose a strict physiological limit for vertical movement (Morales et al., 1996; Giesecke & Gonzalez, 2004), forcing aggregation of planktonic organisms in the upper 50 m layer (Escribano & Hidalgo, 2000).
This is especially the case when the phenomenon of sedimentation occurs, which can reduce light penetration in the euphotic zone of the water column, drastically affecting primary production and consequently population dynamics (Neves et al., 2006).
Exceptionally at sampling station Ss4, where the lowest surface density (74 cell*[mL.sup.-1]) was found, the lower limit of the euphotic zone was 4.95 m.
These eddies introduce nutrients into the euphotic zone, thereby contributing to an increase in primary production.