Download Mountain Environments – Geography 006D

Mountain Environments – Geography 006D
Web-Based Lab: The Resources &
Environment of Glacier National Park,
Montana, USA
Fall 2005
Lab Web Site & Objectives
The US Geological Survey is actively involved in environmental
research in Glacier National Park, Montana. Through their Biological
Resources Division, research is being conducted on Bear Ecology, Global
Climate Change, Whitebark & Limber Pine Ecology, Mountain Landscape
Ecology, Repeat Photography, Amphibian Ecology, and the alpine treeline
ectone, among other things. The work is accomplished through the Northern
Rocky Mountain Science Center – Glacier Field Station.
The web site of the Glacier National Park Field Station is
http://www.nrmsc.usgs.gov/research/gfs_research.htm. See the course
outline as well that lists other useful web sites to learn more about Glacier
National Park. By using the URL provided, go to the web site and start by
reading the fact sheet about the current research projects being
conducted. Then begin examining some of the information about up to five of
the research themes that are being studied in this special mountain
environment. Follow some of the links and see what they turn up, keeping in
mind that the area of emphasis is Glacier National Park, but alo Rocky
Mountain National Park, Olympic and North Cascades National Park, and
Sequoia and Kings Canyon National Park. Below are some specific questions
for you to consider, with emphasis on the alpine treeline ecotone and
pattern-process relationships.
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Study Area
Glacier National Park, a UNESCO-designated Biosphere Reserve, is
located in NW Montana, USA, bordering Canada along the Park’s northern
boundary. The Park is ~ 400,000 ha in size, has peaks with elevations of
nearly 3200 m, and sits astride the Continental Divide, which follows the
Livingston Range in the north and the Lewis Range in the east. The Lewis
Overthrust is the dominant structural feature in the Park. It is responsible
for the emplacement of Precambrian Belt Series formations overtop of
relatively incompetent Cretaceous shales and mudstones. Areas above
treeline in the Livingston Range tend to be steeper and geomorphically more
active, with little colluvial cover.
Glacier National Park is a landscape of immense topographic variation
that has been shaped by tectonic actions associated with mountain building,
over-thrusting and deformation of geologic strata, and the glacial scouring
of the landscape through glacial advances and retreats. During the
Pleistocene period (11,000 – 14,000 years ago), glaciation was widespread in
the Park, carving deep glacial U-shaped valleys and a suite of typical alpine
erosional landforms such as horns, cirques, aretes, cols, paternoster lakes,
and hanging valleys.
Since the recession of Pleistocene ice in the Park, the landscape has
been in a state of disequilibrium as slopes continue to adjust to deglacial
conditions. Landslides are common on valley side-slopes and along the leading
edge of the Lewis Over-thrust, and over 1,000 snow-avalanche paths are
incised on the steep valley side-slopes throughout the Park. Swift-flowing
streams and seasonal flooding characterize valley bottoms, except in areas
where beaver have modified the riparian landscape through dam
emplacement, pond creation, and subsequent sedimentation.
Assignment/Questions & Issues
(1)
Having examined some of the research projects under the active
areas of study that are on-going in the Park and associated with
USGS, prepare a brief summary of at least one project. What is
the project major research objective? What are the primary data
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and methods being used? And what are the basic findings of the
research projects thus far? Remember, factors that influence
treeline are most important to us, but think broadly around the
processes.
(2)
Much of what is being done in the Park is assessing environmental
change. The Repeat Photography research is very specifically
looking at how mountain landscapes in the Park have changed over
time through photography taken at roughly the same geographic
position but at multiple points in time. But other projects are also
considering environmental change and how mountain environments
are responding – some through changes in the extents of glaciers,
some through changes in vegetation, and some through changes in
animal populations or variations in their habitat. Consider the issue
of environmental change, and describe how change is specifically
being manifested in Glacier National Park. Assess, from the
reported research findings as well as images provided, what in
general can be said about environmental change in the Park.
(3)
This section should address research methods and scales of
analysis. What kinds of methods are being used to study mountain
environments in the Park, and what scales are being used to focus
their studies? What is meant by scale here is the ecological scale
at which studies are being conducted. Examples of ecological
scales might include studies involving specific trees, patches (a
contiguous unit of vegetation like a stand of pine trees), slopes,
valleys, or mountain ranges. Besides the ecological scale, what time
scales are being examined – this means how often measurements
are being collected for different studies – each day, week, month,
season, year, decade??? What are the advantages and
disadvantages of the scales being used – what do we learn and what
do we give up?
(4)
So consider each of the above areas of questions. Prepare a Lab
Report that addresses each of them. The paper should be 2-3
pages in length (typed, double-spaced).