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 Plasma-zapping process could yield trans fat-free soybean oil product
02.12.2016 | Purdue University

nachricht New findings about the deformed wing virus, a major factor in honey bee colony mortality
11.11.2016 | Veterinärmedizinische Universität Wien

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: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>