TY - JOUR
T1 - Evidence of hypoxia in the eastern coast of the Gulf of California as induced by stable nitrogen isotopes in surface sediments
AU - Sánchez, Alberto
AU - Aguíñiga-García, Sergio
AU - Rey-Villiers, Néstor
N1 - Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2022/4/15
Y1 - 2022/4/15
N2 - The Gulf of California is a highly biodiverse marine basin located in the northeast Mexican Pacific Ocean. In the past three decades, this basin has experienced increased hypoxia in shallow waters, which threatens its coastal ecosystems. The aim of this study is to analyze δ15N and δ13C isotopes of organic matter in coastal sediments to characterize sources of primary production and shifts in biogeochemical processes that reflect increasing oxygen deficiency in the shallow coast of the eastern Gulf of California. Surface sediments samples were collected from 8 to 47 m deep along the coastal margin of Sinaloa and Sonora. This region is characterized by the development of anthropogenic activities, which could be the main source of organic matter evidenced in the marine environment. The C:N ratio and δ13C of sedimentary organic matter suggest that the dominant source is of marine origin. Values of δ15N measured in organic matter of surface sediments below 15 m are larger than >8‰. This enrichment suggests denitrification and hypoxic conditions in the water column, which could be associated with an increase in the frequency, periodicity, and intensity of shallow hypoxic events in the Gulf of California.
AB - The Gulf of California is a highly biodiverse marine basin located in the northeast Mexican Pacific Ocean. In the past three decades, this basin has experienced increased hypoxia in shallow waters, which threatens its coastal ecosystems. The aim of this study is to analyze δ15N and δ13C isotopes of organic matter in coastal sediments to characterize sources of primary production and shifts in biogeochemical processes that reflect increasing oxygen deficiency in the shallow coast of the eastern Gulf of California. Surface sediments samples were collected from 8 to 47 m deep along the coastal margin of Sinaloa and Sonora. This region is characterized by the development of anthropogenic activities, which could be the main source of organic matter evidenced in the marine environment. The C:N ratio and δ13C of sedimentary organic matter suggest that the dominant source is of marine origin. Values of δ15N measured in organic matter of surface sediments below 15 m are larger than >8‰. This enrichment suggests denitrification and hypoxic conditions in the water column, which could be associated with an increase in the frequency, periodicity, and intensity of shallow hypoxic events in the Gulf of California.
KW - Denitrification
KW - Gulf of California
KW - Hypoxia
KW - Organic matter
KW - Ratio C/N
KW - Stable nitrogen isotopes
UR - http://www.scopus.com/inward/record.url?scp=85127133616&partnerID=8YFLogxK
U2 - 10.1016/j.csr.2022.104716
DO - 10.1016/j.csr.2022.104716
M3 - Artículo
AN - SCOPUS:85127133616
SN - 0278-4343
VL - 239
JO - Continental Shelf Research
JF - Continental Shelf Research
M1 - 104716
ER -