Login

GPC Members Login
If you have any problems or have forgotten your login please contact [email protected]


Reindeer grazing protects tundra plant diversity in a warming climate

Climate warming reduces the number of plant species in the tundra, but plant-eating animals, such as reindeer and voles, can turn this negative effect into something positive. The results of a study coordinated from Umeå University in Sweden are now published in Nature Communications.

"By eating tall and wide-leaved plants, reindeer can increase light availability and thus allow more plant species to co-exist and benefit from warmer conditions," says Elina Kaarlejärvi, post-doctoral researcher at Umeå University, who led the study.

Earlier studies suggest that tundra plant diversity will decrease in response to a warmer climate. However, it is important to know whether the response depends on the abundance of grazing animals, particularly reindeer, voles and lemmings, which are very common in tundra ecosystems. Researchers at Umeå University in Sweden, and Oulu University in Finland, tested this through experimental warming of vegetation on tundra meadows with and without reindeer and voles.

"We found that the warming increased the number of species in plots that were grazed, because it enabled small tundra plants to appear and grow there. But when we fenced reindeer, voles and lemmings out, vegetation became denser and the light was limited. As a result, many small and slowly-growing plant species were lost," says Elina Kaarlejärvi.

The researchers investigated what species appeared and disappeared from the study plots over the course of five years. By doing so, they could test what kinds of species were most affected by warming and grazing. The newly published results suggest that mammalian herbivores could generally help protect diversity in warmer climates by preventing losses of small and slowly-growing species.

The study was performed in Kilpisjärvi in northwest Finland, where the research team tested the importance of grazing animals, warming and nutrient availability by combining small greenhouses that increased the summer temperature by 1-2 degrees Celsius, small fences that excluded reindeer, voles and lemmings, as well as by use of fertilization.

Read the paper: Herbivores rescue diversity in warming tundra by modulating trait-dependent species losses and gains.

Article source: Umeå University.

Image credit: Elina Kaarlejärvi

News

The circadian clock sets the pace of plant growth

The recent award of the Nobel Prize in Physiology or Medicine to the three American researchers Hall, Rosbash and Young for their "discoveries of molecular mechanisms controlling the circadian rhythm" has greatly popularized this term -which comes from the Latin words "circa" (around of) and "die" (day)-. Thanks to the discoveries that these scientists did using the fruit fly, today we know that the organisms have an internal clock built of a set of cellular proteins whose amount oscillates in periods of 24 hours. These oscillations, which are autonomously maintained, explain how living organisms adapt their biological rhythm so that it is synchronized with the Earth's revolutions.


Solving Darwin's 'abominable mystery': How flowering plants conquered the world

Scientists have found an explanation for how flowering plants became dominant so rapidly in ecosystems across the world -- a problem that Charles Darwin called an 'abominable mystery'. In a study published in the open access journal PLOS Biology, Kevin Simonin and Adam Roddy, from San Francisco State University and Yale University respectively, found that flowering plants have small cells relative to other major plant groups and that this small cell size is made possible by a greatly reduced genome size.


How climate change alters plant growth

Global warming affects more than just plant biodiversity - it even alters the way plants grow. A team of researchers at Martin Luther University Halle-Wittenberg (MLU) joined forces with the Leibniz Institute for Plant Biochemistry (IPB) to discover which molecular processes are involved in plant growth. In the current edition of the internationally renowned journal Current Biology, the group presents its latest findings on the mechanism controlling growth at high temperatures. In the future this could help breed plants that are adapted to global warming.