Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ecologists: Screen Plant Imports to Foil Invasives

09.01.2012
A recent analysis led by ecologist Bethany Bradley at the University of Massachusetts Amherst suggests that climate change predicted for the United States will boost demand for imported drought- and heat-tolerant landscaping plants from Africa and the Middle East.

This greatly increases the risk that a new wave of invasives will overrun native ecosystems in the way kudzu, Oriental bittersweet and purple loosestrife have in the past, members of the international team say.

The kudzu invasion of the past few decades saw whole forests overgrown in the Southeast, along with hedgerows, power lines and even houses. In wetlands across the nation, purple loosestrife is crowding out native marsh plants, and Oriental bittersweet, if left unchecked, shades and chokes out native trees, bushes and shrubs along streams, forest and field edges.

Bradley and colleagues recommend that U.S. authorities adopt proactive management practices, in particular pre-emptive screening of nursery stock before new plants are imported, to prevent such an explosion of new invasives. Their conclusions appear in an early online edition of the Feb. 1 issue of Frontiers in Ecology and the Environment.

As the UMass Amherst environmental conservationist and lead author explains, the U.S. Department of Agriculture (USDA) has proposed the Not Authorized Pending Pest Risk Analysis (NAPPRA) rule to regulate the industry. The rule would require importers to notify the USDA of proposed imports. USDA scientists would then conduct a timely risk assessment and issue a recommendation to allow or curtail the import.

“Our study identifies climate change as a risk, which combined with other factors is likely to increase demand for imported heat- and drought-tolerant plants, but this emerging threat is one that policy can effectively address,” Bradley says. “The USDA has tools to reduce import risk and we advocate that now is the time put them in place. Pre-import screening has been tested in Australia for about 10 years now and it’s not foolproof, but it seems to have done a good job of separating the really bad import ideas from more benign introductions.”

Not all imported plants become invasive, but those that do can become a significant threat to native plants and we should not be complacent about the current situation, she says. About 60 percent of plants now considered invasive were introduced deliberately through the plant trade. The other 40 percent are human-related accidental introductions such as seeds stuck in cargo or shipping containers. Only a tiny fraction of non-native introductions are from natural causes such as blowing in with a hurricane, Bradley says.

She and colleagues point out that rising average temperatures in certain regions of the U.S. are already shifting plant hardiness zones northward and the trend is expected to continue globally. Their study suggests that with the earlier onset of spring, warmer winters, economic globalization and increased trade with emerging economies in Asia and Africa, we may face a significant new wave of invasive plant introductions.

For this analysis of the intersection of global trade and climate change, the ecologists used import values from 1989 to 2010 to identify emerging trade partners, because earlier studies had established a clear link between increased trade and the number of invasive species. They found 42 emerging trade partners poised to supply new nursery plant varieties including Thailand, Egypt, Saudi Arabia, Ecuador, Argentina and several in equatorial Africa.

The rate of introduction is steepest in the early stages of new trade relationships, the authors say. “Unfortunately, increasing the variety and availability of non-native, drought-tolerant species could also increase the probability of introducing species capable of invading dryland regions.” Bradley adds, “In the desert Southwest this has already been happening with xeriscaping, which is becoming more and more popular.” Xeriscaping refers to gardening with low or no need for watering.

Bradley and colleagues’ work focuses on introduction, the first of three stages of invasion, because “stopping invasions before they start is the most effective way of preventing widespread ecological and economic impacts,” she says. “Globalization has accelerated the rate of introduction from a few species at the first colonization of North America to now, when we probably see thousands of new species each year. All we need is another kudzu to have a big impact.”

This work was supported by the National Science Foundation's National Center for Ecological Analysis and Synthesis.

Bethany Bradley | Newswise Science News
Further information:
http://www.umass.edu

More articles from Ecology, The Environment and Conservation:

nachricht Scientists on the road to discovering impact of urban road dust
18.01.2018 | University of Alberta

nachricht Gran Chaco: Biodiversity at High Risk
17.01.2018 | Humboldt-Universität zu Berlin

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: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

Im Focus: A thermometer for the oceans

Measurement of noble gases in Antarctic ice cores

The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Polymers Based on Boron?

18.01.2018 | Life Sciences

Bioengineered soft microfibers improve T-cell production

18.01.2018 | Life Sciences

World’s oldest known oxygen oasis discovered

18.01.2018 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>