Sediment biogeochemistry data obtained from cores retrieved at stations S1, S2, and S3 (see Fig 1A) during the austral summer-autumn period in 2015.

The range, standard deviations (±), and mean were calculated from sediment intervals values collected from 0–20 cm. It is important to note that sediment cores were analyzed under two contrasting biogeochemical conditions: anoxic (April, pre-El Niño) and oxic (July, post El Niño) conditions. The abbreviations used in the table correspond to the following parameters: TIC (total inorganic carbon), TC (total carbon) TN (total nitrogen), TS (total sulfur), AVS (Acid Volatile Sulfides), CRS (chromium reducible sulfur).