Why ecological studies in mountain regions?

Dr. Christophe RANDIN Leysin, October 2 2015 - LAS

Variation of elevation = changes in climate condition = changes in species composition + diversity of habitats

Photo: C.Randin

Why are mountain ecosystems so important?

Elev

ation

Photo: P. Vittoz and C.Randin

http://www.leysin-commune.ch

Leysin 1350 m Top of Tour d’Aï 2330 mAlmost 1000 m verticalForecasted temperature in Leysin (8-10 am) : 6.4 – 9.2 °CTemperature on the top of Tour d’Aï? 0.9 – 3.7 °C

Temperature shows similar trends with elevation and latitude

(a) (b)

ΔΤ of 10°C : Δlatitude = 1800 km ~ Δelevation = 2500 m

Scandinavia Eastern Swiss Alps

Harbritter et al., 2013

Why are mountain ecosystems so important?

Mountains create their own climate!

Photo: C. Randin

Photos: C.Randin

Why are mountain ecosystems so important?

Mountains are Islands in the Sky

Systems ± connected

High endemism = Species Factories

Cold adapted species

Exposed to climate warming

Why are mountain ecosystems so important?

Mountains are Islands in the Sky

Why are mountain ecosystems so important?

Photo: C.Randin &M. Wilhelm

http://www.leysin-commune.ch

Photo: C.Randin

Photo: C.Randin

The treeline ecotone

Körner, C. & Paulsen, J. (2004) A world-wide study of high altitude treeline temperatures. Journal of Biogeography, 31, 713-732.

Photo: C.Randin

Aeschimann D, Burdet H (1994) Flore de la Suisse et des territoires limitrophes, le nouveau Binz. 2ndedition, Editions du Griffon, Neuchâtel, Switzerland.Theurillat JP (1991) Les étages de végétation dans les Alpes centrales occidentales (Vegetationlevels in the western Central Alps). Saussurea, 22. 103-147.

Gran Sasso, Italy (42° N)Tromsø, Norway (70° N) Chimborazo, Equateur (0°)

> 300 m a.s.l. > 2600 m a.s.l. > 4000 m a.s.l.

Photos: C.Randin

Photo: C.Randin

Stone pine on the Clochers d’Arpette – 2800 m

Predicted treeline shift for the XXIst century

Actuelle: ~2250 m

2050: ~3500 m

2030: ~2700 m

Trees on the top of Mt Blanc?

Photo: C.Randin

Photo: C.Randin

Above the treeline?

Scherrer, D. & Koerner, C. (2010) Infra-red thermometry of alpine landscapes challenges climatic warming projections. Global Change Biology, 16, 2602-2613.Scherrer, D. & Korner, C. (2011) Topographically controlled thermal-habitat differentiation buffers alpine plant diversity against climate warming. Journal of Biogeography, 38, 406-416.

Forts contrastes de versant!3. Le climat de l’étage alpin

Körner, C. (2003) Alpine plant life, 2nd edn. Springer, Berlin.

Photo: C.Randin

Topographic factors

Photos: C.Randin

(Loiseleuria procumbens)

Photos: C.Randin

Körner, C. (2003) Alpine plant life, 2nd edn. Springer, Berlin.

(Salix reticulata)

Photos: C.Randin & M.Wilhelm

Photo: C.RandinRebetez and Reinhard (2007) Theoretical and Applied Climatology

The starting point(It’s Getting Hot In

Here!)

Château-d’Oex – Western Swiss Alps

Northern hemisphere

Temperature anomalies for the 20st century

1.5Switzerland

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0.5

0

-0.5

-1

1900 1920 1940 1960 1980 2000

Thank you for your attention!