BACKGROUND Biological dinitrogen (N2) fixation, the reduction of atmospheric N2 to
ammonia, is important for maintaining the fertility of the oceans by providing biologically …

Nitrogen (N) is used in many of life's fundamental biomolecules, and it is also a participant in
environmental redox chemistry. Biogeochemical processes control the amount and form of N …

Marine diazotrophs convert dinitrogen (N 2) gas into bioavailable nitrogen (N), supporting
life in the global ocean. In 2012, the first version of the global oceanic diazotroph database …

Abstract Subtropical gyres cover 26%–29% of the world's surface ocean and are
conventionally regarded as ocean deserts due to their permanent stratification, depleted …

Direct observations indicate that the global ocean oxygen inventory is decreasing. Climate
models consistently confirm this decline and predict continuing and accelerating ocean …

This chapter addresses the biogeochemical cycles of carbon dioxide (CO2), methane (CH4),
and nitrous oxide (N2O). The three greenhouse gases have increased in the atmosphere …

Global nitrogen fixation contributes 413 Tg of reactive nitrogen (Nr) to terrestrial and marine
ecosystems annually of which anthropogenic activities are responsible for half, 210 Tg N …

Microbial activity is a fundamental component of oceanic nutrient cycles. Photosynthetic
microbes, collectively termed phytoplankton, are responsible for the vast majority of primary …

Uncertainty in the global patterns of marine nitrogen fixation limits our understanding of the
response of the ocean's nitrogen and carbon cycles to environmental change. The …

PISCES-v2 is a biogeochemical model which simulates the lower trophic levels of marine
ecosystem (phytoplankton, microzooplankton and mesozooplankton) and the …