AlpineSubalpInteractns KSamelson by rnrj9uO

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									Winter Ecological Interactions
between Alpine and Subalpine
        Ecosystems




                   Kate Samelson
                   12 March 2006
                        EBIO 4120
                 Winter Ecology – Spring 2006
   Mountain Research Station – University of Colorado, Boulder
      Physical Environment
Subalpine                                Alpine/Tundra
  Environment                              Environment
• Elevation: 10,000 to 11,500 ft         • Elevation: 11,500 ft and above
• Dominated mostly by Englemann’s        • Vegetation includes lichens,
    spruce and subalpine fir                 grasses, sedges, shrubs and
•   Precipitation: 30-35in/yr, mostly        mosses.
    as snow                              •   Precipitation: 6-10in/yr, including
•   Lingering snowpacks keep forest          melted snow
    floor moist for much of the year     •   Winds can be stronger than
•   Deer mice, snowshoe hare,                100mph
    bobcats and Steller’s jays amongst   •   Pikas, marmots, mountain goats,
    other inhabit the subalpine              sheep, elk and beetles all live in
    environment                              the tundra environment
Organic materials and
nutrients are transported
via fluvial means in
aquatic systems.

Fluvial processes are not
present in alpine
environments.

How are alpine and
subalpine ecosystems
connected if not by
fluvial processes, and
how does this change
affect the
communities??
   Alpine and subalpine
ecosystems are connected
through groundwater and
     wind processes.
               Wind
Organic materials and nutrients are
transported downwind from the alpine
to the subalpine.

The greatest intake of organic
materials and nutrients is going to be
along treeline.
      Ecological Differences
Alpine                        Subalpine
 The tundra ecosystem is      The ecosystem is
  losing organic materials      uptaking organic matter
  and nutrients downwind,       and nutrients from
  and therefore the amount      upwind, and therefore
  of organic matter being       the amount organic
  decomposed decreases.         matter being decomposed
  This lowers respiration       is increased. This raises
  rates in the community.       respiration rates.
 Primary productivity to      Primary productivity to
  respiration ratios are >1     respiration ratios are <1
Subsurface Groundwater
          In alpine and subalpine
          ecosystems, subsurface
          runoff from snow can
          account for up to 90% of
          the total flow of the basin.

          The short residence time of
          water in the basin limits
          the ability of biota to
          uptake atmospherically
          deposited nitrogen.
                 Conclusions
Alpine and subalpine ecosystems are connected through wind
processes and subsurface groundwater.

Wind scouring blows nutrient and nitrogen rich snow and
organic materials from the tundra into the subalpine.

Productivity rates in the alpine ecosystem are decreasing,
while productivity rates in the subalpine ecosystem are
increasing.

Groundwater interactions between the alpine and subalpine
communities are often minimal and ecologically less
significant.

Interactions between alpine and subalpine ecosystems is of
great importance to the biota of both communities and
without such, the two ecosystems would be drastically
different.
                      Bibliography
Liptzin, Daniel, Seastedt, Timothy, University of Colorado, Boulder, CO, USA
    Heterogenity in soil nutrients in the forest-alpine tundra ecotone.

								
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