Scientists have discovered that elevated atmospheric CO2 (carbon dioxide) can suppress plant growth when increases of this important greenhouse gas are combined with a broad suite of already-occurring environmental changes. According to Christopher Field, project leader and director of the new Department of Global Ecology of the Carnegie Institution of Washington, "We are now getting a much richer picture of ecosystem responses to global environmental changes, and the traditional view that elevated CO2 always stimulates plant growth simply isn’t correct." The research is published in the December 6, 2002, issue of Science.
Many past studies of global-change impacts on plants and ecosystems have focused on responses to increases in atmospheric CO2. But realistically, global changes are much more than just elevated CO2. They include global warming, altered rainfall, and increases in biologically available nitrogen compounds produced during fossil-fuel combustion. These other global changes can have major impacts on plants and ecosystems. A new study by scientists at the Carnegie Institution of Washington, the Nature Conservancy, and Stanford University shows, for the first time, how these other global changes alter the response of a natural ecosystem to increased atmospheric CO2. According to lead author Rebecca Shaw, "In the third year of the experiment, plant growth increased in the plots treated with CO2 alone, as in many other experiments. It also increased in plots exposed to the other global changes--warming, increased precipitation, and fertilizing with nitrogen --alone or in combination. But, when we added carbon dioxide, the effect of the other treatments was suppressed. The elevated CO2 in this situation pushed the response back toward the initial conditions."
Over the last hundred years, the concentration of CO2 in the atmosphere has increased by more than 30%. The planet has warmed by about 1 ºF. Rainfall has increased in some regions and decreased in others. And human actions have more than doubled inputs of biologically available nitrogen. Elevated atmospheric CO2 increases plant growth in many experiments, but most past experiments studied impacts of CO2 alone or in combination with one other factor. The results of the Carnegie-led experiment reveal new dimensions of ecosystem responses to global change. In the California grassland studied by this team, elevated CO2 suppresses plant growth in many treatments, especially treatments where growth at normal CO2 is fastest. Field noted, "When we look at impacts of realistic global changes on whole ecosystems, we see a broad range of responses. We do not yet know whether responses will be similar in other ecosystems, but our wide range of treatments helps open the door to understanding global-change impacts on ecosystems not yet studied."
Rebecca Shaw | EurekAlert!
Dune ecosystem modelling
23.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
Understanding animal social networks can aid wildlife conservation
23.06.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine
Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...
19.06.2017 | Event News
13.06.2017 | Event News
13.06.2017 | Event News
23.06.2017 | Physics and Astronomy
23.06.2017 | Physics and Astronomy
23.06.2017 | Information Technology