A new paper co-written by four University of Montana researchers finds that humans have more than doubled tropical nitrogen inputs.
Benjamin Sullivan, a researcher working with UM College of Forestry and Conservation Professor Cory Cleveland, led the team that looked at the nitrogen cycle in tropical rain forests. Sullivan and his colleagues used a new method to demonstrate that biological nitrogen fixation in tropical rain forests may be less than a quarter of previous estimates.
Nitrogen is an essential nutrient for plant and animal life. It’s required in many basic molecules, like DNA and amino acids. Nitrogen enters the environment either through a microbial process called biological nitrogen fixation or through human activity, such as fertilization and fossil-fuel consumption.
Too much nitrogen, however, leads to dead zones, pollutes air and drinking water, contributes to a number of human illnesses, and can affect ecosystems negatively. That could be a problem, given the high biodiversity of tropical rain forests and their important role in the global carbon cycle and the Earth’s climate.
“This research fundamentally changes our understanding of the tropical nitrogen cycle,” said Sullivan. “It shows that few ecosystems on Earth have escaped the impact of human activity.”
He notes that human impacts on the nitrogen cycle typically are greatest where biological nitrogen fixation is low and human inputs of nitrogen are high – like in many parts of North America, including Montana.
Past research has assumed that tropical rain forests have high levels of biological nitrogen fixation and that humans add relatively little nitrogen to tropical ecosystems. In fact, by reducing estimates of naturally occurring nitrogen inputs, “this research shows that human impacts on the nitrogen cycle are even bigger than we thought. Preserving human and ecosystem health requires immediate steps to solve this growing problem,” Cleveland said.
Sullivan worked with UM doctoral student Megan Nasto and researcher Bill Smith. Smith provided the spatial data analysis that put Sullivan’s field and lab-tested results into a global context. Co-authors also include UM alumna Sasha Reed at the U.S. Geological Survey, and researchers at the University of Colorado-Boulder and the University of Connecticut.
The research paper, titled “Spatially Robust Estimates of Biological Nitrogen (N) Fixation Imply Substantial Human Alteration of the Tropical N Cycle,” was published in the journal Proceedings of the National Academy of Sciences.
Benjamin Sullivan | Eurek Alert!
Upcycling of PET Bottles: New Ideas for Resource Cycles in Germany
25.06.2018 | Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF
Dry landscapes can increase disease transmission
20.06.2018 | Forschungsverbund Berlin e.V.
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences