Elemental and isotopic composition of particular organic carbon and nitrogen in the Gulf of México

Yéssica Vanessa Contreras Pacheco1, Juan Carlos Herguera2, Sharon Z Herzka3, Doreny Bobadilla4, María Reyna Barradas4 and Gerardo Quintanilla2, (1)Center for Scientific Research and Higher Education at Ensenada, Ensenada, Mexico, (2)Center for Scientific Research and Higher Education at Ensenada, Ensenada, BJ, Mexico, (3)Center for Scientific Research and Higher Education at Ensenada, Biological Oceanography, Ensenada, BJ, Mexico, (4)Center for Scientific Research and Higher Education at Ensenada, BJ, Mexico
Abstract:
We present the spatial distributions and water column profiles of the concentration and isotopic composition of particulate organic carbon and nitrogen in the deep-water region of the Gulf of Mexico, based on results obtained from 130 stations that were sampled during oceanographic cruises XIXIMI 4, 5, 6 and 7, with the objective of characterizing the patterns of their spatial and temporal distributions and their relationships with physical, chemical and biological variables.

Here we characterize the spatial variability and relative abundances of particulate organic carbon and nitrogen and its isotopic compositions, as well as the C/N ratio. We interpret the observed carbon isotopic distribution patterns in terms of the importance of different sources either continental or marine carbon. We further speculate on the sources of nitrate to the surface ocean to understand the different controls of biological production, as well as its transfer and recycling processes in the water column in the deep waters of the Gulf of Mexico to the S of the 25˚N.