Biological nitrogen fixation and stable isotopes of carbon in seston during Meteor cruise M130

Biological nitrogen fixation is a key process balancing the loss of combined nitrogen in the marine nitrogen cycle. Its relevance in upwelling systems is not fully resolved. This dataset contains rates of nitrogen fixation through the euphotic layer in two size fractions measured following Montoya et al (1996) technique. It also contains the stable isotopes of carbon in seston expressed in delta notation (δ13C, ‰, VPDB). We sampled in the region of the Guinea Dome and Equatorial Atlantic Ocean along 23°W during Meteor cruise M130 in August-September 2016. Water samples were collected by niskin bottles attached to a rosette equipped with CTD sensors. Incubations were done in on-deck incubators refrigerated by running surface water continuously and simulating the light intensity of each depth by neutral density filters or meshes.

生物固氮（biological nitrogen fixation）是平衡海洋氮循环中化合态氮损失的关键过程，其在上升流系统中的相关作用尚未完全明晰。本数据集包含采用Montoya等人（1996）方法测定的真光层（euphotic layer）内两个粒径分级的固氮速率数据，同时包含以δ符号标记的悬浮颗粒物碳稳定同位素数据（δ¹³C，‰，VPDB）。本数据集的采样工作于2016年8-9月随“流星”号科考航次M130开展，采样区域为沿23°W经线的几内亚穹顶（Guinea Dome）与大西洋赤道海域。水样由搭载温盐深（CTD）传感器的采水架配套的尼斯金采水器（niskin bottles）收集。培养实验采用连续流通表层水制冷的甲板培养箱完成，并通过中性密度滤膜或网幕模拟各深度的原位光照强度。