极地研究2025，Vol.37Issue(4)：658-667,10.DOI:10.13679/j.jdyj.20240023
硝酸盐及其氮、氧同位素指示白令海沉积物中的硝酸盐转化过程
Concentrations of nitrate and its dual isotopes in Bering Sea sediments reveal nitrate transformation processes
摘要
Abstract
Simultaneous nitrification and denitrification processes happened in marine sediments affect the nitrate(NO3-)cycling in the Ocean.Studies of nitrogen(N)transformation processes occurring in Bering Sea sedi-ments are crucial for improving our understanding of the N cycling in polar and subpolar marine regions.In this study,we conducted preliminary analyses of nitrate and its stable nitrogen and oxygen isotopes(δ15N-NO3-,δ18O-NO3-)in the sediment pore water in Bering Sea sediments.Samples were extracted from sediment cores collected during the 5th Chinese Arctic Research Expedition from the Bering Sea Basin(BL-10)and the 7th Chinese Arctic Research Expedition from the Bering Sea shelf(B12).The results show that:(1)at BL-10 station,nitrate concentration in pore water was 0.61～22.52 μmol·L-1,δ15N-NO3-was 3.6‰～17.8‰,and δ18O-NO3-was 10.5‰～20.9‰,suggesting coupling between nitrification-denitrification process.(2)At B12 station,the nitrate concentration in sediment pore water was 0.20～1.61 μmol·L-1,in 0～2 cm δ15N-NO3-was 10.3‰～16.4‰,δ18O-NO3-was 13.2‰～19.7‰,which was significantly lower than that in bottom sea(18.60 μmol·L-1).This indicates intense denitrification in the surface sediment pore water.(3)Denitrification appears to be more intense in shelf than in basin sediments because of the combined in-fluence of water depth,primary productivity,and sediment organic carbon content.关键词
硝酸盐/氮氧同位素/沉积物间隙水/转化过程/白令海Key words
nitrate/nitrogen and oxygen isotopes/sediment pore water/transformation processes/Bering Sea引用本文复制引用
陈佳钦,金海燕,陈玲,庄燕培,任健,季仲强,白有成,杨志,李杨杰,陈建芳..硝酸盐及其氮、氧同位素指示白令海沉积物中的硝酸盐转化过程[J].极地研究,2025,37(4):658-667,10.基金项目
国家重点研发计划(2019YFE0120900)和国家自然科学基金(41406217,41776205,42306261,42376251)资助 （2019YFE0120900）
