When exposed to increased carbon dioxide, precipitation, nitrogen and temperature – all expected results of climate change – yellow starthistle in some cases grew to six times its normal size while the other grassland species remained relatively unchanged, according to a Purdue University study published in the early online edition of the journal Ecological Applications. The plants were compared with those grown under ambient conditions.
"The rest of the grassland didn't respond much to changes in conditions except nitrogen," said Jeff Dukes, a Purdue associate professor of forestry and natural resources and the study's lead author. "We're likely to see these carbon dioxide concentrations in the second half of this century. Our results suggest that yellow starthistle will be a very happy camper in the coming decades."
The study is one of the first comparing the growth of invasive species versus their local competitors under future climate scenarios. Dukes believes the results indicate problems land managers and crop growers could see in the coming decades, and not just with yellow starthistle.
"Plants are going to respond in a number of ways to climate change. Sometimes, the species we depend on will benefit, but other times, it will be the weedy, problematic species that benefit most, and there can be economic and ecological damages associated that people should be aware of," Dukes said. "These problems with yellow starthistle aren't going to go away on their own. If anything it's going to become more of a problem than it is now."
Yellow starthistle is a significant weed in the West, especially in California, where it has a longer growing season than native plants and depletes ground moisture, affecting water supplies.
"It reduces the quality of the area for animal forage, is toxic to horses and when it forms spines, cattle don't want to eat it," Dukes said. "Many consider yellow starthistle to be the worst grassland weed in the West."
The decreased pasture production, lost water, and control costs associated with yellow starthistle cause economic impacts in many western states. Experts suggest that in Idaho alone, the weed may cause more than $12 million a year in economic damage and that yellow starthistle reduces pasture values by 6 percent to 7 percent across the state of California.
Dukes said all plants increased in size as expected when exposed to more nitrogen. But yellow starthistle was especially responsive to increased carbon dioxide.
That might be in part because the weed can gain access to more soil resources, Dukes said. Grassland plants' stomata, small porelike openings on the leaves, don't have to be open as wide to take in carbon dioxide when there is a larger concentration in the air. Those smaller stomata allow less water to escape, and the extra water in the soil could favor yellow starthistle. The added carbon dioxide also changed the mix of species competing with the weed and may have allowed it to grow a more effective root system.
"It was an impressive increase in growth," Dukes said. "It was one of the largest responses to elevated carbon dioxide ever observed."
Biological control species introduced to control yellow starthistle have not been effective enough, and Dukes said it is becoming urgent that better controls be developed to address invasive species that could cause significant damage to pasture, cropland and wildlands.
The National Science Foundation and the David and Lucile Packard Foundation funded the research, which was carried out in collaboration with researchers at the University of Massachusetts Boston, Stanford University and the Carnegie Institution for Science.
Writer: Brian Wallheimer, 765-496-2050, email@example.com
Source: Jeff Dukes, 765-496-1446, firstname.lastname@example.orgAg Communications: (765) 494-2722;
Brian Wallheimer | EurekAlert!
Safeguarding sustainability through forest certification mapping
27.06.2017 | International Institute for Applied Systems Analysis (IIASA)
Dune ecosystem modelling
26.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.
For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...
What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.
To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...
The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....
A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...
Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision
Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...
19.07.2017 | Event News
12.07.2017 | Event News
12.07.2017 | Event News
20.07.2017 | Information Technology
20.07.2017 | Materials Sciences
20.07.2017 | Physics and Astronomy