Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Screening horticultural imports: New models assess plant risk through better analysis

29.06.2012
Model asks if importing a plant is worth the risk of environmental damage, economic costs
Weedy plants, many introduced to the U.S. for sale through plant nurseries, are responsible for extensive environmental damage and economic costs. Although legislation restricts the introduction of certain species, the procedures used to select species for inclusion on the restricted list are haphazard and out of date.

To meet the need for more systematic weed risk analysis, researchers at the University of Georgia Odum School of Ecology and the University of California, Davis have developed a "cost-sensitive" model to determine when importing a given plant is worth the risk. Their work was published in the May edition of the journal Ecosphere.

Although the problems caused by invasive plants are well known, Odum School postdoctoral associate J.P. Schmidt, the lead scientist on the study, said the U.S. has historically placed very few restrictions on the import of plants.

According to UC Davis economist and study co-author Mike Springborn, "our approach represents a shift from the current practice of scrambling to address invasives only after they are already established. In this paper, we develop tools for making informed decisions ahead of time about which plants have an acceptable level of risk given their anticipated benefits. We now have the combined biological and economic tools to take an informed look before we leap with trade in new species."

The model uses statistical procedures to assess how likely a plant is to become a weed. To do this, it compares the estimated probability with the average costs of a new weed and the expected losses from foregone sales of non-weed species that are presumably safe. Using the model as a screening tool, the researchers say, would provide a net economic benefit of at least $80,000 to $140,000 per species assessed, which could translate into tens of millions of dollars in total.

Had the proposed screening system been in place historically, they calculated—using just low-end estimates of invasive species damages—that one third of the most noxious species could have been excluded. To realize this benefit, only 15 percent of potential introductions would need to be prohibited.

At its core, the model consists of two parts. First, the researchers sought to identify a small number of plant traits that could be used to predict invasiveness.

"Amazingly, we found that just four traits could discriminate pest from non-pest species with an impressive degree of accuracy," Schmidt said. "Namely, pest species tend to have some combination of the following traits: seeds that are in the mid-range of seed sizes, that have higher chromosome counts than their close relatives, that have affinities for both wetland and upland habitats and that have large native ranges."

"Second," said co-author John Drake, an associate professor at the Odum School, "we asked where to draw the proverbial line-in-the-sand—in this case the line between probable pests and probable non-pests—which requires accounting for the value of the ornamental plant trade and the costs associated with weeds. The economically optimal decision rule is the one that settles that line where it exactly balances the costs from invasion with the benefits from trade."

Schmidt explained that the cost of mistakenly keeping out a non-invasive plant was far lower than the cost of mistakenly allowing an invasive plant in.

To make these results equally accessible to scientists, decision-makers and the interested public, the researchers then encapsulated the resulting decision rule in a series of four graphics. Every plant species can be placed somewhere on these diagrams. The location on the diagram indicates the economically optimal policy-either to admit or deny import.

Although these methods were developed to aid decision-making about potential plant pests, the techniques used may be helpful for other problems in environmental management, for instance in prioritizing rare species for conservation.

Results from the analysis inspired a companion study by Schmidt, Drake and Odum School assistant research scientist Patrick Stephens, in the journal Ecological Applications, which contrasts invasive and rare plants of North America. For more on this study, see http://www.esajournals.org/doi/abs/10.1890/11-1915.1.

Using a much larger data set—the roughly 15,000 species native to the U.S. and Canada—this second study developed predictive models to distinguish species classified as pests together with rankings developed by the Nature Conservancy concerning extinction vulnerability.

"In summary, decisions about allowing plants into the U.S. are being made every day," Schmidt said. "Our models could help to better guide those decisions, potentially saving tens of millions to billions of dollars in costs associated with plant invasions."

The full text of the Ecosphere article is available at http://www.esajournals.org/doi/pdf/10.1890/ES12-00055.1

J.P. Schmidt | EurekAlert!
Further information:
http://www.uga.edu

More articles from Ecology, The Environment and Conservation:

nachricht Value from wastewater
16.08.2017 | Hochschule Landshut

nachricht Species Richness – a false friend? Scientists want to improve biodiversity assessments
01.08.2017 | Carl von Ossietzky-Universität Oldenburg

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>