%0 Journal Article %9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES %A Marquez-Artavia, A. %A Sanchez-Velasco, L. %A Barton, E. D. %A Paulmier, Aurélien %A Santamaria-Del-Angel, E. %A Beier, E. %T A suboxic chlorophyll-a maximum persists within the Pacific oxygen minimum zone off Mexico %D 2019 %L fdi:010077727 %G ENG %J Deep-Sea Research Part II : Topical Studies in Oceanography %@ 0967-0645 %K Chlorophyll maxima ; Suboxia ; Persistence ; Euphotic zone ; Mexican Pacific %K MEXIQUE ; PACIFIQUE %M ISI:000504782200008 %N No Spécial %P art. 104686 [8] %R 10.1016/j.dsr2.2019.104686 %U https://www.documentation.ird.fr/hor/fdi:010077727 %> https://www.documentation.ird.fr/intranet/publi/2020/01/010077727.pdf %V 169 %W Horizon (IRD) %X The tropical Oxygen Minimum Zones (OMZ) are known to shelter a chlorophyll-a maximum (CM) within suboxic waters (<20 mu mol kg(-1)), below other chlorophyll-a maxima and with an unknown temporal variability in the Pacific OMZ off Mexico. Here, 1161 chlorophyll-a fluorescence and oxygen profiles collected between 2003 and 2016 were used to describe statistically the physical situation in which the suboxic-CM was found. Results indicate that the suboxic-CM was a persistent feature at seasonal scale at depths between 40 and 190 m at an average density potential anomaly of 26 +/- 0.2 kg m(-3), related to the Subtropical Subsurface Water, which is nearly unaffected by mixing with other water masses. The suboxic-CM south of 21 degrees N was generally associated with the upper limit of the suboxic waters of the OMZ. In this region, the distance between the suboxic waters and the euphotic zone (1% of surface irradiance) was > - 25 m year-round, which suggests that persistent low-light levels allow development of the suboxic-CM. The persistence of the suboxic-CM is consistent with its association with a stable microbial community. The effects on the ecosystem and biogeochemical cycles remain to be investigated. %$ 032 ; 036