Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

In grasslands, longer spring growing season offsets higher summer temperatures

01.03.2016

North American grasslands face mixed bag of climate change effects

Grasslands across North America will face higher summer temperatures and widespread drought by the end of the century, according to a new study.


Kendall Grassland in southeastern Arizona is one of many sites in the research project.

Credit: R.L. Scott, USDA-ARS

But those negative effects in vegetation growth will be largely offset, the research predicts, by an earlier start to the spring growing season and warmer winter temperatures.

Led by ecologists Andrew Richardson and Koen Hufkens of Harvard University, a team of researchers developed a detailed model that enables predictions of how grasslands from Canada to Mexico will react to climate change.

The model is described in a paper published today in the journal Nature Climate Change.

New insights into climate change effects on grasslands

"This research brings new insights into predicting future climate-driven changes in grasslands," says Elizabeth Blood, program director in the National Science Foundation's Division of Environmental Biology, which funded the research. "The results show that annual grassland cover and productivity will increase despite drought-induced reductions in summer productivity and cover."

Ultimately the growing season gets split into two parts, Hufkens said. "You have an earlier spring flush of vegetation, followed by a summer depression where the vegetation withers, then at the end of the season, you see the vegetation rebound again."

Adds Richardson, "The good news is that total grassland productivity is not going to decline, at least for most of the region. But the bad news is that we're going to have this new seasonality that is outside of current practices for rangeland management -- and how to adapt to that is unknown."

To understand the effects of climate change on grasslands, the scientists created a model of the hydrology and vegetation of the region. They used data from the PhenoCam Network, a collection of some 250 Internet-connected cameras that capture images of local vegetation conditions every half-hour.

Using 14 sites that represent a variety of climates, the biologists ran the model against a metric of "greenness" to ensure that it could reproduce results in line with real-world observations.

"These were sites from across North America, from Canada to New Mexico and from California to Illinois," Richardson said. "We used the greenness of the vegetation as a proxy for the activity of that vegetation. We were then able to run the model into the future."

The region was divided into thousands of 10 square-kilometer blocks, allowing researchers to spot important differences in the response to climate change.

"That allows us to look at how patterns emerge in different areas," Hufkens said.

Importantly, Richardson said, the model also uses a daily rather than monthly time step.

Changing seasonal patterns bring challenges

"Grasslands are different than forests in that they respond very quickly to moisture pulses," said Richardson. "This model takes advantage of that -- by running at a daily time scale, it can better represent changing patterns."

The changing conditions could present challenges for farmers, ranchers and others who rely on predictable seasonal changes to manage the landscape.

"These shifting seasons will present new tests for management practices," Richardson cautioned.

For grasslands, the increases in production and losses due to higher summer temperatures largely balance out, Hufkens said.

Although the results suggest that climate change may have some positive effects, both Hufkens and Richardson warned that they are the result of a delicate balance.

"It's getting more arid and that's causing more intense summer droughts, but because of a changing seasonality, vegetation growth is shifting," said Richardson.

The negative effects of drought on ecosystem production can be offset, he believes. "But that raises new questions about appropriate management responses," he said.

"Relying on this increase in productivity, or expecting that climate change will have long-term benefits because of results like this, is like playing the lottery -- the odds are not very good."

Media Contact

Cheryl Dybas
cdybas@nsf.gov
703-292-7734

 @NSF

http://www.nsf.gov 

Cheryl Dybas | EurekAlert!

More articles from Agricultural and Forestry Science:

nachricht Energy crop production on conservation lands may not boost greenhouse gases
13.03.2017 | Penn State

nachricht How nature creates forest diversity
07.03.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>