Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Topography shapes biodiversity, and not only through temperature


A warming climate is likely to drive species to higher, cooler altitudes. A new study highlights a less obvious, yet crucial way in which their new habitat could differ from the one they leave behind.

Mountains are home to many living species, with biodiversity typically peaking at mid-altitudes. Scientists have long struggled to explain why this is the case, invoking factors such as low temperatures at high elevations or human disturbance further down.

Mutually isolated mountain peaks and valleys (gray/white) and much more connected mid-altitudes (yellow-red gradient).

Image: EPFL

According to new research, mid-altitudes host the largest number of species because the size and the connectedness of similar habitats are greatest there. One implication of their findings, presented in the Proceedings of the National Academy of Sciences, is that moving to higher elevations to adapt to a warming climate could drive species into habitats with a whole different set of spatial properties.

Many factors determine the number species that can co-exist on a patch of land. Large areas with similar properties typically host more species than small ones. And their biodiversity can be increased further if many similar habitats are connected.

In mountainous terrain, other factors come into play, such as temperature, biological productivity, and exposition. By transposing the findings from flat land to mountainous terrain, a team of researchers from across Switzerland has found a new way to explain the observation that biodiversity in mountainous terrain tends to peak at mid-altitudes.

“In mountainous terrain, peaks and valleys are isolated habitats, like islands in the ocean, whereas mid-elevation sites form well-connected patches,” explains Enrico Bertuzzo, a researcher at the Ecohydrology Lab at EPFL and first author of the study. “Given that habitat area and connectivity foster biodiversity, whereas isolation favors the dominance of few species, we hypothesized that topography itself could be playing a key role in regulating how biodiversity varies with elevation.”

Biodiversity is often studied on idealized cone-shaped mountains, where similar habitats are assumed to be found at similar altitudes. In this case, habitats get smaller with increasing altitude, and their species richness is predicted to decrease, leading biodiversity to peak at foot of the cone and steadily decrease with elevation. Instead, Bertuzzo and his coauthors took a more laborious approach.

“Rather than simplifying mountainous terrain to perfect cones or regular hills, our starting point was to consider it in all of its complexity,” explains Florian Altermatt from the Institute of Evolutionary Biology and Environmental Studies at the University of Zurich.

To test their intuition that the very structure a landscape can shape biodiversity patterns, Bertuzzo and his coauthors let loose a large number of virtual species on a mountainous terrain in a computer simulation. Each virtual species was assigned an optimal altitude at which it could thrive, and these altitudes were distributed uniformly across all the elevations considered. When the researchers let the virtual species compete for habitats on landscapes modeled on real-life ones, their simulations confirmed their intuition: topography alone was enough to explain biodiversity patterns observed in nature.

“Other factors, like temperature, productivity, etc., are obviously also important, but they inevitably act on top of the unavoidable effect provided by the landscape structure,“ says Altermatt.

These findings are of particular relevance in a warming world. “Understanding the relation between elevation and biodiversity is crucial to predict how the distribution of species will change in response to climate change,” says Bertuzzo.

“Warmer temperatures will cause species' niches to shift upwards. The same ecological community will therefore move up the mountain, where it will find a different spatial composition, both in terms of available area and connectivity. Our findings underscore the importance of considering these factors to predict future changes.”

This study was carried out by researchers from the Laboratory for Ecohydrology at the EPFL, the Department of Aquatic Ecology at the Swiss Federal Institute of Aquatic Science and Technology (Eawag), the Department of Evolutionary Biology and Environmental Studies at the University of Zürich, and the Department of Civil and Environmental Engineering at Princeton University.

Enrico Bertuzzo, Francesco Carrara, Lorenzo Maric, Florian Altermatt, Ignacio Rodriguez-Iturbe, and Andrea Rinaldoa. Geomorphic controls on elevational gradients of species richness. Proceedings of the National Academy of Sciences. February 1, 2016. doi: 10.1073/pnas.1518922113

Prof. Andrea Rinaldo
Labor für Ökohydrologie
ETH Lausanne
Tel. +41 21 693 80 34
Mobile +41 79 226 70 83

Prof. Florian Altermatt
Institut für Evolutionsbiologie und Umweltwissenschaften
Universität Zürich
Tel. +41 58 765 55 92

Weitere Informationen:

Kurt Bodenmüller | Universität Zürich

Further reports about: Biology EPFL Ecohydrology Environmental mountainous terrain terrain

More articles from Earth Sciences:

nachricht UCI and NASA document accelerated glacier melting in West Antarctica
26.10.2016 | University of California - Irvine

nachricht Ice shelf vibrations cause unusual waves in Antarctic atmosphere
25.10.2016 | American Geophysical Union

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Greater Range and Longer Lifetime

26.10.2016 | Power and Electrical Engineering

VDI presents International Bionic Award of the Schauenburg Foundation

26.10.2016 | Awards Funding

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

More VideoLinks >>>