Taxonomy term

nitrogen

A rocky source of nitrogen

Calculations of the planet’s nitrogen balance have always been off: plants and soils seem to sequester far more nitrogen than expected. The atmosphere has long been thought of as the only major source of nitrogen, but a new study indicates an additional source: as much as a quarter of Earth’s terrestrial nitrogen may be supplied by eroding bedrock.

07 Aug 2018

From farm to filter: Restored wetlands remediate nitrogen pollution

The early 20th-century invention of a nitrogen-fixation process revolutionized agriculture and made it possible to feed the planet’s growing population. But nitrogen runoff is polluting our waterways and suffocating aquatic life. Now, researchers looking for ways to reverse that trend are turning farmland into wetlands to filter nitrogen from streams and rivers.
20 Apr 2018

Burning grass releases more nitrogen pollution than burning wood

Smoke from fires — whether from wildfires or from residential and agricultural grass and crop burning — carries pollutants into the air that affect climate and can be toxic to humans and ecosystems. According to new research, smoke from crop and grass fires appears to contain higher levels of some hazardous nitrogen-containing chemicals than wood fire smoke. The work also calls into question whether certain chemicals commonly used as distinctive signatures of biomass burning are still valid.

06 Feb 2017

Nutrient deficiency delayed life after mass extinction

After Earth’s most severe mass extinction, life took up to 9 million years to recover — millions of years longer than after other extinction events. New research published in Geology suggests that a collapse in the ocean’s productivity might have been the cause.

25 Nov 2016

Convection formed Pluto's polygons

Among Pluto’s peculiar surface features, many of which were first seen just last year when NASA’s New Horizons spacecraft zipped by the dwarf planet, are polygon-shaped rises covering parts of a large equatorial basin known as Sputnik Planum. The basin is known to be filled mainly with ices of nitrogen, methane and carbon monoxide, but the origin of the polygons has been debated. In a pair of new studies published in Nature, two teams of researchers now attribute the distinctive shapes to convection within underlying layers of frozen nitrogen.

24 Oct 2016

Uranium contamination in aquifers could be linked to nitrate

Nitrogen is an essential nutrient for plant life, but plants can only take up so much so fast. When excess nitrogen enters the environment by way of fertilizer and manure runoff, as well as in automobile and industrial emissions, it becomes a pollutant that can leach into waterways, carrying with it unintended — and often undesirable — consequences. In a new study, researchers have found evidence of one such consequence: elevated uranium levels in two major U.S. aquifers.

17 Feb 2016

Sunlight liberates nitrogen from urban grime

Cities are dirty. That’s obvious from all the grime that collects on glass, metal and other urban surfaces. But new research shows that not everything in that grunge is staying put at ground level, and that the grime — and the nitrogen in it — is contributing to air pollution in ways scientists aren’t accounting for.
 
24 Dec 2015

Ancient lakes may have been refuges for early life

All life needs nitrogen to build essential molecules like proteins, RNA and DNA. And to acquire nitrogen, cells need molybdenum. But molybdenum is thought to have been very scarce in Mesoproterozoic oceans 1.6 billion to 1 billion years ago, potentially stalling the evolution and diversification of life in this period, which was then entirely microscopic. New research, however, is revealing that lakes during this time contained relatively high levels of molybdenum, suggesting life may have continued evolving in those settings.
 
03 Nov 2015

Thank subduction for Earth's nitrogen-rich air

Plate tectonics underlies many of Earth’s distinctive features, from its ever-shifting continents to its colliding mountain ranges and continuously forming crust at mid-ocean ridges. According to a new study, the process might also explain another of our planet’s peculiarities: its nitrogen-rich atmosphere.

 
08 Mar 2015