Navigation Links
UC Davis researcher leads climate-change discovery
Date:6/18/2008

A team of researchers led by a first-year UC Davis faculty member has resolved a longstanding paradox in the plant world, which should lead to far more accurate predictions of global climate change.

A paper describing the research will be published online Wednesday (June 18) by the journal Nature.

The paradox centers on puzzling aspects of the nitrogen cycle in temperate and tropical forests. Defying laws of supply and demand, trees capable of extracting nitrogen directly from the atmosphere (a process called nitrogen fixation) often thrive where it is readily available in the soil, but not where it is in short supply.

Nitrogen is essential to all life on Earth, and determines how much carbon dioxide ecosystems can absorb from the atmosphere, said UC Davis assistant professor Benjamin Houlton, who tackled the problem with colleagues including top international ecologist Peter Vitousek, the Clifford G. Morrison Professor in Population and Resource Studies at Stanford University.

"You would expect that nitrogen-fixing species would have a competitive advantage in ecosystems where nitrogen is in low supply, but not where nitrogen is abundant, because fixation is energetically very costly to an organism," says Houlton, lead author of the paper.

"And in fact that's the way ecologists have found it works in the open ocean and in lakes. But in mature temperate forests, where the soils have limited amounts of nitrogen, nitrogen-fixing tree species are scarce. And in the tropical lowland forests, which are nitrogen-rich, nitrogen-fixing trees often are abundant.

Houlton and his collaborators found the explanation lies in the key roles played by two other factors: temperature and the abundance of another key element, phosphorus.

Temperature, they determined, affects the activity of a nitrogen-fixing enzyme called nitrogenase. In cooler, temperate climates, more of the enzyme is needed to fix a given amount of nitrogen. This higher cost would offset the benefit of nitrogen fixation in temperate forests, despite low-nitrogen soils.

In tropical forests, it's the link between nitrogen and phosphorus that explains the abundance of nitrogen-fixing species.

"Many tropical forest soils are severely depleted in phosphorus, even where nitrogen is relatively abundant," said Houlton. "The extra nitrogen added to the soil by nitrogen-fixers helps mobilize phosphorus, making it easier for roots to absorb. That stimulates the growth of these plant species and puts them at a competitive advantage, despite the energetic cost of nitrogen fixation."


'/>"/>

Contact: Benjamin Houlton
bzhoulton@ucdavis.edu
530-752-2210
University of California - Davis
Source:Eurekalert

Related biology news :

1. UC Davis bird-flu expert calls for changes in early-warning system
2. UC Davis researchers discover how HIV turns food-poisoning into lethal infection
3. UC Davis stem researchers demonstrate safety of gene therapy using adult stem cells
4. Researchers identify proteins involved in new neurodegenerative syndrome
5. Texas researchers and educators head for Antarctica
6. MGH researchers describe new way to identify, evolve novel enzymes
7. University of Pennsylvania researchers develop formula to gauge risk of disease clusters
8. University of Oregon researcher finds that on waters surface, nitric acid is not so tough
9. U of MN researchers discover noninvasive diagnostic tool for brain diseases
10. U of Minnesota researchers discover noninvasive diagnostic tool for brain diseases
11. Researchers discover new strategies for antibiotic resistance
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/20/2016)... , June 20, 2016 Securus Technologies, ... technology solutions for public safety, investigation, corrections and ... prisons involved, it has secured the final acceptance ... facilities for Managed Access Systems (MAS) installed. Furthermore, ... facilities to be installed by October, 2016. MAS ...
(Date:6/9/2016)... Finland , June 9, 2016 ... National Police deploy Teleste,s video security solution to ensure the ... France during the major tournament ... data communications systems and services, announced today that its video ... Prefecture to back up public safety across the ...
(Date:6/2/2016)... 2016   The Weather Company , an IBM Business ... industry-first capability in which consumers will be able to interact ... questions via voice or text and receive relevant information about ... Marketers have long sought an advertising solution that can ... personal, relevant and valuable; and can scale across millions of ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... ... June 24, 2016 , ... Researchers at the Universita Politecnica delle Marche ... with peritoneal or pleural mesothelioma. Their findings are the subject of a new article ... Diagnostic biomarkers are signposts in the blood, lung fluid or tissue of mesothelioma patients ...
(Date:6/23/2016)... 23, 2016   Boston Biomedical , an ... designed to target cancer stemness pathways, announced that ... Orphan Drug Designation from the U.S. Food and ... cancer, including gastroesophageal junction (GEJ) cancer. Napabucasin is ... inhibit cancer stemness pathways by targeting STAT3, and ...
(Date:6/23/2016)... HOUSTON , June 23, 2016 ... agreement with the Cy-Fair Sports Association to serve ... of the agreement, Houston Methodist Willowbrook will provide ... education and connectivity with association coaches, volunteers, athletes ... partner with the Cy-Fair Sports Association and to ...
(Date:6/23/2016)... -- The Biodesign Challenge (BDC), a university competition that asks ... systems and biotechnology, announced its winning teams at the ... York City . The teams, chosen ... MoMA,s Celeste Bartos Theater during the daylong summit. Keynote ... of architecture and design, and Suzanne Lee , ...
Breaking Biology Technology: