Did nuclear transformations inside Earth form nitrogen, oxygen, and water?

Aquatic nitrogen transformations at low oxygen concentrations.

Nitrite and nitrous oxide made up 40% of the hypolimnetic dissolved inorganic nitrogen in mesotrophic Lake Rotoiti, New Zealand, prior to hypolimnetic anoxia. Up to 120 mg of N m-3 as nitrite and 20 mg of N m-3 as nitrous oxide accumulated, whereas dissolved-oxygen concentrations remained between 1.0 and 0.2 g m-3 and were totally consumed when the hypolimnion became completely anoxic. Assays o...

Nitrogen Transformations

No other element essential for life takes as many forms in soil as nitrogen (N), and transformations among these forms are mostly mediated by microbes. Soil microbiology thus plays yet another crucial role in ecosystem function: in most terrestrial ecosystems N limits plant growth, and thus net primary production—the productive capacity of the ecosystem—can be regulated by the rates at which so...

Sensing oxygen inside and out

Neuroendocrine cells act as oxygen sensors in animals from fish to humans, but the evolutionary origins of these cells are only just becoming clear.

Chapter 14 - Nitrogen Transformations

No other element essential for life takes as many forms in soil as nitrogen (N), and transformations among these forms are mostly mediated by microbes. Soil microbiology thus plays yet another crucial role in ecosystem function: in most terrestrial ecosystems N limits plant growth, and thus net primary production— the productive capacity of the ecosystem—can be regulated by the rates at which s...

Growth and nitrogen content of sunflower as affected by the rate and form of nitrogen