Weeds head for the hills as climate warms
Tuesday 11 July 2017 - Scientists are warning that alpine plants are at risk of extinction as climate change, skiing and
mountain tourism spread weeds to higher altitudes.
The latest research shows that as temperatures have risen, plants have spread up mountainsides, with weeds being the
fastest movers, spreading to higher altitudes twice as fast as native plants.
“We know native plants are moving up mountains as climate warms, but until now no-one had looked at how non-native weeds
might respond,” says Professor Philip Hulme of the Bio-Protection Research Centre, Lincoln University.
The international team of researchers discovered that weeds quickly outpaced other plants. It seems that roads are
amongst the culprits, with traffic helping to transport seeds further.
These findings should raise concerns for New Zealand’s unique alpine environments explains Professor Hulme. “I suspect
the situation is possibly more dire in New Zealand given that our lowland regions are far more invaded by non-native
weeds than similar regions in Europe. Our montane (mountain ecosystems) regions are coming under increasing pressure
from tourism, skiing developments and other infrastructure such as roads,” he continues.
The research, published in Nature Climate Change, used more than 130,000 records of 1334 plant species collected over 20 years in a single region of the European Alps.
“The challenge for New Zealand is that we are no longer collecting the systematic, long-term data on how our flora are
changing in these environments,” says Professor Hulme, “such data are essential if we want to keep our glorious mountain
landscapes free of weeds such as gorse, broom and wilding pines.”
The authors of the study point out that such rapid spread into vulnerable habitats is a further threat to species
already stressed by higher temperatures.
“We must take action soon otherwise our native alpine plant communities are likely to suffer dramatic changes with
ongoing warming and increasing human activity in mountain regions,” concludes Professor Hulme.
*Dainese M, Aikio S, Hulme PE, Bertolli A, Prosser F, Marini L (2017) Non-native plant species are moving upwards faster
than natives in the Alps. Nature Climate Change DOI: 10.1038/NCLIMATE3337
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About the Bio-Protection Research Centre
The Bio-Protection Research Centre is a Centre of Research Excellence funded by the New Zealand Government. It was
established in 2003 to drive innovation in sustainable approaches to pest, pathogen and weed control. The Centre has six
partner institutes: AgResearch, Lincoln University, Massey University, Plant & Food Research, Scion and the University of Canterbury, with members throughout New Zealand.