Beavers are diverse forest landscapers

June 10, 2020

Beavers are ecosystem engineers that cut down trees to build dams, eventually causing floods. Beaver-induced floods make forest landscapes and habitats increasingly diverse, but very little is known about the long-term effects of beavers on European landscapes. Researchers at the University of Eastern Finland and the University of Helsinki examined the history and occurrence of beaver-induced floods and patch dynamics in southern Finland. They used a unique dataset of field observations from 1970 to 2018.

Floods caused by beavers over the course of history form a network of different habitats that remain interconnected even for long periods of time.

"Beavers can help to restore wetland ecosystems and entire boreal forests, and they also help in conserving the biodiversity of these environments," Researcher Sonja Kivinen from the University of Eastern Finland says.

The European beaver was hunted to extinction in the 19th century Finland. Nowadays, the study area is home to the American beaver, which was introduced there in the 1950s. The American beaver builds similar dams as the European one.

"The spread of the beaver in our study area has created a diverse and constantly changing mosaic of beaver ponds and beaver meadows of different ages," Kivinen says.

In 49 years, number of beaver-induced flood sites grew 11-fold

The researchers observed that the number of beaver-induced flood sites grew by more than 11-fold over the study period. In addition to creating new flood sites, beavers also often use old sites to cause new floods. The duration of an individual flood and the frequency of floods can vary greatly between different flood sites, resulting in an abundance of habitat patches with different environmental conditions.

"Thanks to beaver activity, there is a unique richness of wetlands in the forest landscape: flowages dominated by bushes, beaver meadows, and deadwood that can be used by various other species," University Lecturer Petri Nummi from the University of Helsinki says.

Indeed, beaver-induced disturbances are more predictable in diversifying the forest landscape than for example forest fires or storms.
-end-
The study was carried out within the IBC-Carbon project funded by the Strategic Research Council at the Academy of Finland.

Research article:

Kivinen, S., Nummi, P. & Kumpula, T. Beaver-induced spatiotemporal patch dynamics affect landscape-level environmental heterogeneity. Environmental Research Letters, in press. Available online: https://doi.org/10.1088/1748-9326/ab9924

For further information, please contact:

Sonja Kivinen, Department of Geographical and Historical Studies, University of Eastern Finland,

tel. +358405884185, sonja.kivinen(at)uef.fi

Petri Nummi, Department of Forest Sciences, University of Helsinki, tel. +358504486160

Timo Kumpula, Department of Geographical and Historical Studies, University of Eastern Finland, tel. +358503728566

University of Eastern Finland

Related Floods Articles from Brightsurf:

Mystery of glacial lake floods solved
A long-standing mystery in the study of glaciers was recently and serendipitously solved by a team led by University of Hawai'i at Mānoa.

Consequences of glacier shrinkage
Scientists from Heidelberg University have investigated the causes of a glacial lake outburst flood in the Ladakh region of India.

Seismic monitoring may improve early warnings for glacial lake outburst floods
Vibrations in the ground may help to improve advanced warnings about sudden floods that result from glacial melting, according to a study published today in Science Advances.

An international study analyzes five hundred years of floods in Europe
An international research project coordinated by the Vienna University of Technology (TU Wien), with participation from researchers of the University of Barcelona, shows for the first time that flood pattern over the last decades in Europe have changed compared to past centuries.

Beavers are diverse forest landscapers
Beavers are ecosystem engineers that cut down trees to build dams, eventually causing floods.

How catastrophic outburst floods may have carved Greenland's 'grand canyon'
For years, geologists have debated how and when canyons under the Greenland Ice Sheet formed, especially one called 'Greenland's Grand Canyon.' Its shape suggests it was carved by running water and glaciers, but until now its genesis remained unknown, scientists at UMass Amherst and Denmark's Center for Ice and Climate say.

Catastrophic outburst floods carved Greenland's 'Grand Canyon'
Buried a mile beneath Greenland's thick ice sheet is a network of canyons so deep and long that the largest of these has been called Greenland's 'Grand Canyon.' This megacanyon's shape suggests it was carved by running water prior to widespread glaciation, but exactly when and how the island's grandest canyon formed are topics of intense debate.

Natural bayou better when floods threaten Houston
A comparison of flood plains around Houston's two major bayous shows the natural Buffalo Bayou is far better at managing floodwaters than the channelized Brays Bayou.

Texas A&M researchers develop flooding prediction tool
By incorporating the architecture of city drainage systems and readings from flood gauges into a comprehensive statistical framework, researchers at Texas A&M University can now accurately predict the evolution of floods in extreme situations like hurricanes.

New satellite may make flood prediction easier
A satellite on schedule to launch in 2021 could offer a more comprehensive look at flooding in vulnerable, under-studied parts of the world, including much of Africa, South America and Indonesia, a new study has found.

Read More: Floods News and Floods Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.