English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Nitrogen (N2) fixation and nitrate assimilation activities were examined simultaneously using a 15N tracer in February and March 2007 along the 155° E meridian from the equator to 44° N in the western North Pacific Ocean. N2 fixation was detected only to the south of 28° N, where the nitrate + nitrite (N+N) concentration was <30 nM in the upper mixed layer; the concentration ranged from 12.8 to 152 μmol N m-2 d-1. High N2 fixation rates were observed from 16° N to 24° N, where rel- atively high dust depositions and low concentrations (<100 nM) of soluble reactive phosphorus (SRP) were observed. The depth-integrated nitrate assimilation in the euphotic zone showed no significant latitudinal trend, varying between 184 and 349 μmol N m-2 d-1 in the area from the equator to 24° N, where the water column was stable. Toward the north of 28° N, nitrate assimilation was enhanced, while N2 fixation became insignificant. The contribution of N2 fixation to new production (= N2 fixa- tion + nitrate assimilation) ranged from 2 to 37%, and the highest contribution was observed at 24° N at the center of the subtropical gyre, where the highest N2 fixation occurred. From the equator to 24° N, the coefficient of variation of nitrate assimilation was 20%, while that of N2 fixation was 80%, indicating that the latter is more responsible for the latitudinal variation in the contribution of N2 fixation to new production.

Contribution of N2 fixation to new production in the western North Pacific Ocean along 155°E