A new study by an international group of scientists in this month's edition of the journal Science has found that one-third of the nitrogen entering the world's oceans from the atmosphere is man-made. This is important, since nitrogen causes an increase in marine biological activity and carbon dioxide uptake, which in turn produces the potent greenhouse gas nitrous oxide (N2O). This is the first time a study looked at these impacts on the open oceans instead of just the land.
How does man influence this?
--The use of fertilizers
--The burning of fossil fuels in cars and power stations.
Below are a couple of exerpts from the NASA Earth Observatory news release..........
The study found that increasing quantities of atmospheric anthropogenic fixed nitrogen entering the open ocean could account for around one third of the ocean's external (non-recycled) nitrogen supply and up to three per cent of the annual new marine biological production.
While the increased biological activity has the beneficial effect of drawing down man-made CO2 from the atmosphere, the researchers found that around two-thirds of this is offset by the increase in harmful N20 emissions.
According to the study, the effect of the increasing atmospheric nitrogen deposition are expected to continue to grow in the future.