Article: 

Theurillat, J.P., Felber, F., Geissler, P., Gobat, J.-M., Fierz, M., 
        Fischlin, A., Kuepfer, P., Schluessel, A., Velluti, C., Zhao, G.-F. & 
        Williams, J., 1998.  Sensitivity of plant and soil ecosystems of the Alps 
        to climate change. In: Cebon, P., Dahinden, U., Davies, H.C., Imboden, 
        D.M. & Jaeger, C.C. (eds.), Views from the Alps: regional perspectives 
        on climate change. MIT Press, Boston, Massachusetts a.o., pp. 289-308.

Abstract:

  • In highly structured vegetation, synusiae of the understory are unlikely to react directly to climate change but rather only indirectly to a change in their microhabitat conditions.
  • Present climatic climax plant communities are likely to persist in climate change as edaphic climaxes.
  • Present edaphic climaxes are likely to persist temporally and spatially in climate change according to their buffering capacities, that is, so far as their limiting factors are not changed.
  • Natural landscape is likely to change at a differential rate, according to its component elements (lagging vs. rapid change).
  • The cultural landscape that will undergo climate change may be very different from today's.
  • The response of species, plant communities and landscape to a temperature increase is not likely to be linear, and there may be an inertia of 1-2 K.
  • A temperature increase of 3-4 K would very likely have a profound effect at every level of complexity, since it equals the temperature amplitude of an entire vegetation belt.
  • Fragmentation, diminution of populations, and selective extinctions of high alpine and arctic stenoicious relict plant populations of bryophytes and vascular plants are likely over the entire Alps if the temperature increases by 3-4 K.
  • Alpine endemics restricted to tops of low mountains (i.ee., those lacking nival belts, mainly in the eastern Alps) are likely to be severely endangered of disappearance/extinction if the temperature increases by 3-4 K.
  • Phenotypic plasticity and genetic adaptation might buffer the effect of climatic change in some cases for vascular plants, and perhaps more frequently for bryophytes.
  • Changes in forest types might occur in 30-55 percent of the forested area for an increase of 1-1.4 K, and in up to 55-89 percent for a 2-2.8 K increase, according to static modeling of Swiss forests (Kienast, Brzeziecki, and Wildi 1995, 1996).
  • Adaptation of forests and tree species to climate change cannot be suitably established without taking into account the typically high genetic diversity of tree populations and the maintainance of that diversity.
  • For an increase of 1-2 K in the mean annual temperature, the present upper subalpine forest limit is not likely to shift upward much more than 100-200 meters, because of its temperature-related inertia, but the kamp[zone might move into the low alpine belt in favorable places.
  • For an increase of 3-4 K in the mean annual temperature, the kamp[zone would be very likely to invade the alpine belt, with an upward shift of the forest limit into the low alpine belt.
  • With an increase of 3-4 K in the mean annual temperature, subalpine elements would be likely to invade the entire alpine vegetation belt, and new plant communities would be likely to replace in part the present communities.
  • For an increase of 1-2 K in the mean annual temperature, human use might slow down the subalpine vegetation's upward shift, in particular that of heaths, shrubs, and trees, through an intensification of pasturing. In contrast, humans could also accelerate the shift through abandoning agricultural activities and afforestion of the upper subalpine belt.
  • The upward shift of the present alpine vegetation into the nival belt, where it exists, might epend more on edaphic factors than on climatic onces because of the upper alpine and nival belts increasing steepness. Therefore, it is likely that present alpine plant communities on gentle slopes would disappear.
  • Carbonate soils would likely be less prone to react to climate change than noncarbonate soils, thus acting nonsynergistically on vegetation change.
  • Processes in soils operate at different rates, and many happen on the timescale of one year or tens of years. The accepted idea that soils evolve on a scale of centuries or millenia must be abandoned in considerations of climate change.
  • Organic matter in soils is the key factor that would be affected, directly or indirectly, qualitatively and quantitatively, by climate change, but its evolution cannot be dissociated from that of soil nitrogen content.
  • Nitrogen content, form, and cycle would be affected, and cannot be dissociated from changes in organic matter, as, for example, an increase in humification.

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