Format

Send to:

Choose Destination
See comment in PubMed Commons below
Proc Natl Acad Sci U S A. 2009 Jul 28;106(30):12400-5. doi: 10.1073/pnas.0900921106. Epub 2009 Jul 10.

Species-driven changes in nitrogen cycling can provide a mechanism for plant invasions.

Author information

  • 1School of Biological Sciences, University of Nebraska, 348 Manter Hall, Lincoln, NE 68588, USA.

Abstract

Traits that permit successful invasions have often seemed idiosyncratic, and the key biological traits identified vary widely among species. This fundamentally limits our ability to determine the invasion potential of a species. However, ultimately, successful invaders must have positive growth rates that longer term result in higher biomass accumulation than competing established species. In many terrestrial ecosystems nitrogen limits plant growth, and is a key factor determining productivity and the outcome of competition among species. Plant nitrogen use may provide a powerful framework to evaluate the invasive potential of a species in nitrogen-limiting ecosystems. Six mechanisms influence plant nitrogen use or acquisition: photosynthetic tissue allocation, photosynthetic nitrogen use efficiency, nitrogen fixation, nitrogen-leaching losses, gross nitrogen mineralization, and plant nitrogen residence time. Here we show that among these alternatives, the key mechanism allowing invasion for Pinus strobus into nitrogen limited grasslands was its higher nitrogen residence time. This higher nitrogen residence time created a positive feedback that redistributed nitrogen from the soil into the plant. This positive feedback allowed P. strobus to accumulate twice as much nitrogen in its tissues and four times as much nitrogen to photosynthetic tissues, as compared with other plant species. In turn, this larger leaf nitrogen pool increased total plant carbon gain of P. strobus two- to sevenfold as compared with other plant species. Thus our data illustrate that plant species can change internal ecosystem nitrogen cycling feedbacks and this mechanism can allow them to gain a competitive advantage over other plant species.

PMID:
19592506
[PubMed - indexed for MEDLINE]
PMCID:
PMC2718360
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk