Researchers say we can't count on plants forever for CO2 storage

Apr 12, 2006
Researchers say we can't count on plants forever for CO2 storage

Rising carbon dioxide levels in the atmosphere will over time lead to nutrient limitations to grassland productivity, according to a study by researchers at the University of Michigan and the University of Minnesota. An article to be published Thursday in the journal Nature, which is based on a six-year study—the longest known study of its kind—says that decision-makers need to understand the relationship between fossil fuel emissions and plant productivity and nutrients when they set policy. Grasslands amount to about 30 percent of the arable land surface of the world.

"The results suggest that our ecosystem likely cannot get enough nutrients under elevated levels of CO2," said David Ellsworth, associate professor of plant ecophysiology at the University of Michigan School of Natural Resources and Environment. "As a result, we think that the soil will be unable to sustain growth and productivity increases from enriched CO2 over time."

At Cedar Creek Natural History Area in central Minnesota, the researchers grew 16 native or naturalized plant species in two types of plots. The soil in one plot type was enriched with nitrogen while the soil in the other type was not. The purpose of the study was to document the plant's ability to grow biomass and flourish in a nutrient-poor soil as carbon dioxide levels increased to concentrations likely to be reached in the middle of this century.

The study's results are consistent with previous experimental studies of the interaction between carbon dioxide and nitrogen in agricultural and forest plantation systems, according to Ellsworth. "This suggests that there may be no 'free-lunch' of nitrogen for plants under CO2 enrichment for this long."

With its wide range of species types and combinations, including mixtures, the study provides a broad test of carbon dioxide and nitrogen interactions under contrasting low and high nitrogen supply rates. It also includes measurements of root biomass. Previous studies have been done with a single or few types of plant species. These studies had greater amounts of nitrogen added and included no below-ground biomass measures.

The article, "Nitrogen limitation constrains sustainability of ecosystem response to CO2," was written by Peter B. Reich, Sarah E. Hobbie, Tali Lee, David S. Ellsworth, Jason B. West, David Tilman, Johannes M.H. Knops, Shahid Naeem and Jared Trost.

Source: University of Michigan

Explore further: Red moon at night; stargazer's delight

add to favorites email to friend print save as pdf

Related Stories

US power plant emissions down, study finds

Jan 09, 2014

Power plants that use natural gas and a new technology to squeeze more energy from the fuel release far less of the greenhouse gas carbon dioxide than coal-fired power plants do, according to a new analysis ...

Recommended for you

Red moon at night; stargazer's delight

5 hours ago

Monday night's lunar eclipse proved just as delightful as expected to those able to view it. On the East Coast, cloudy skies may have gotten in the way, but at the National Science Foundation's National Optical ...

Meteorites yield clues to Martian early atmosphere

7 hours ago

(Phys.org) —Geologists who analyzed 40 meteorites that fell to Earth from Mars unlocked secrets of the Martian atmosphere hidden in the chemical signatures of these ancient rocks. Their study, published ...

Let's put a sailboat on Titan

10 hours ago

The large moons orbiting the gas giants in our solar system have been getting increasing attention in recent years. Titan, Saturn's largest moon, is the only natural satellite known to house a thick atmosphere. ...

User comments : 0

More news stories

Meteorites yield clues to Martian early atmosphere

(Phys.org) —Geologists who analyzed 40 meteorites that fell to Earth from Mars unlocked secrets of the Martian atmosphere hidden in the chemical signatures of these ancient rocks. Their study, published ...

Red moon at night; stargazer's delight

Monday night's lunar eclipse proved just as delightful as expected to those able to view it. On the East Coast, cloudy skies may have gotten in the way, but at the National Science Foundation's National Optical ...

Let's put a sailboat on Titan

The large moons orbiting the gas giants in our solar system have been getting increasing attention in recent years. Titan, Saturn's largest moon, is the only natural satellite known to house a thick atmosphere. ...

Down's chromosome cause genome-wide disruption

The extra copy of Chromosome 21 that causes Down's syndrome throws a spanner into the workings of all the other chromosomes as well, said a study published Wednesday that surprised its authors.