Feeds

Greener Arctic may be down to lemming poo, not climate

Swarming sex-mad rodents fertilise grasses

Intelligent flash storage arrays

Recent satellite observations showing "greening" of some Arctic regions - until now put down to global warming permitting plants to grow more easily in the frozen north - may in fact be explained by large numbers of lemmings defecating on the affected areas, so fertilising green plants.

"Our paper confirms that we really need to be careful attributing the greening of the Arctic to global warming alone. We have shown that lemmings can promote similar greening, through the increase of grasses and sedges, as warming does in Arctic regions where lemmings are present and go through dramatic population cycles," said lead author of the study David Johnson, a biology prof at the University of Texas.

Johnson and his colleagues measured the effect of lemmings on Arctic vegetation by studying special control plots of land near Barrow, Alaska. Some plots had lemmings on and some didn't. According to the scientists:

These results suggest that sustained lemming activity promotes a higher biomass of vascular plant functional types than would be expected without their presence and highlights the importance of considering herbivory when interpreting patterns of greening in the Arctic.

According to a statement announcing publication of the research:

The increase of grass and sedge could be due to changes in nutrient availability in soils from the addition of urine and faeces from the lemmings, or by simply reducing competition for space by keeping bryophyte and lichen abundance low, as well as reducing the amount of standing dead grass and sedge litter.

Lemming populations have historically gone through periods of highs and lows, which researchers believe have played a key role in regulating many properties and processes of tundra ecosystems.

The tiny rodents are best known perhaps for their tendency to migrate suddenly across long distances, sometimes including lengthy swims which may begin with a mass leap off a cliff (erroneously assumed to be mass suicide by some). In fact the lemmings do sometimes attempt swims too long for them and drown en masse, but normally they reach land again.

The migrations are thought to be driven in part by the lemmings' frequent sudden population increases. It now appears that the small sex-mad creatures may be causing green grasses and sedges to spread rapidly across tundra regions by fertilising the ground with their wastes and perhaps also by carrying the grasses' seeds about with them as well.

Arctic greening may actually reduce atmospheric carbon as the new plants suck it in: conversely higher temperatures in the north could cause soils to release more greenhouse gases, though recent research has cast doubt on such ideas. In any case, future forecasts will now have to factor in the Lemming Effect.

Johnson and his colleagues' research is published in the journal Environmental Research Letters. It can be read online here. ®

Intelligent flash storage arrays

More from The Register

next story
Antarctic ice THICKER than first feared – penguin-bot boffins
Robo-sub scans freezing waters, rocks warming models
I'll be back (and forward): Hollywood's time travel tribulations
Quick, call the Time Cops to sort out this paradox!
Your PHONE is slowly KILLING YOU
Doctors find new Digitillnesses - 'text neck' and 'telepressure'
Reuse the Force, Luke: SpaceX's Elon Musk reveals X-WING designs
And a floating carrier for recyclable rockets
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
Bond villains lament as Wicked Lasers withdraw death ray
Want to arm that shark? Better get in there quick
prev story

Whitepapers

10 ways wire data helps conquer IT complexity
IT teams can automatically detect problems across the IT environment, spot data theft, select unique pieces of transaction payloads to send to a data source, and more.
Why CIOs should rethink endpoint data protection in the age of mobility
Assessing trends in data protection, specifically with respect to mobile devices, BYOD, and remote employees.
Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Mitigating web security risk with SSL certificates
Web-based systems are essential tools for running business processes and delivering services to customers.