Download aspen - School of Natural Resources and Environment

An Integrated Geoecosystem-Remote Sensing
Approach To Aspen Ecosystem Management
In Northern Lower Michigan
School of Natural Resources & Environment
McIntire-Stennis Program
Burt Barnes, Kathleen Bergen
Graduate Students: Ephraim Zimmerman
Kara Moore, Catherine Yanca
October 28, 2002
Collaborator
Tom Crow
USFS North Central Research Station
Rationale
• Following massive logging and post-logging fires in
northern Lower Michigan in the mid-to-late 19th Century,
the original pine and hemlock-northern hardwood
forests were changed to stands primarily dominated by
bigtooth and trembling aspens.
• Now, 80-100 years later, aspens are declining and are
being replaced by other species in patterns determined
by site conditions and forest history.
• These changes are not well understood, yet have
profound ecological, social, and economic implications.
Goal
• Demonstrate the applicability of the landscape
ecosystem approach coupled with remote
sensing/GIS methods to develop a model of the
spatial and successional status of the aspen
resource for ecosystem management.
Objectives
•Determine the successional pathways for selected
ecosystems at the 4000-ha University of Michigan
biological Station (UMBS), northern Lower Michigan
•Characterize the role of red maple, northern red oak,
and eastern white pine in forming 21st Century forest
communities for selected landforms and ecosystems.
•Model the decline of the aspen resource using an
ecosystem approach at multiple spatial scales coupled
with remote sensing and GIS methods.
Approach
• An ecosystem map of the area and permanent sample
plots were used to determine successional change at
multiple spatial scales.
• The composition, structure, and successional trends
were determined for 7 aspen- dominated ecosystem
types
• The occurrence and successional role of species
replacing aspen (red maple, northern red oak, and
eastern white pine) in diverse ecosystems were
determined
Results
Aspen
• On moraine landforms, aspens are being
replaced by northern-hardwood species.
• In contrast, aspens on outwash plain landforms
are being replaced by white and red pines and
red maple, depending on ecosystem type.
• Different trends of occurrence and succession
for red maple, northern red oak, and white pine
for a diverse set of ecosystem types was
observed and described.
Different Landscape Ecosystems Types,
Different Successional Pathways
Dry
Mesic
Wet-Mesic
Red Maple
• Success of red maple is highly ecosystem-dependent
• Contrary to the prevailing view, red maple will not
become dominant in the long run on dry and dry-mesic
ecosystems at UMBS
although many of its clones
may persist indefinitely.
90.0
Dominant Overstory
Dominant
Overstory
Subdominant
Overstory
Subdominant Overstory
Understory
Understory
80.0
Relative Density (%)
70.0
60.0
50.0
40.0
30.0
20.0
10.0
0.0
1
4
24
25
Low-elevation outwash Low-elevation outwash
(Pellston Plain)
wetlands (Pellston Plain)
36
37
High-elevation severely
burned outwash plain
41
42
High-elevation banded
outwash plain
44
45
High-elevation calcareous
outwash plain
Ecosystem Type
Comparison of red maple relative density in three forest layers for selected
ecosystem types, outwash physiographic system, UMBS, Cheboygan and
Emmet Co., northern Lower Michigan.
Northern Red Oak
• Red oak understory density was considerably lower
than overstory density in most ecosystems types due to:
– limited light under dense northern hardwood canopy in mesic
ecosystems
– severe site conditions, lack of fire, and heavy deer browsing in
dry ecosystem types
• Higher red oak density in outwash-over moraine
ecosystem type
– open, patchy aspen canopy
– sandy-loam bands in C horizon
450
400
Overstory
Understory
Density (stems/ha)
350
300
250
200
150
100
50
0
1
36
37
74
44
45
40
59
60
76
77
Ecosystem Type
Comparison of northern red oak density in three forest layers for selected
ecosystem types, outwash physiographic system, UMBS, Cheboygan and
Emmet Co., northern Lower Michigan.
96+97
Remote Sensing
• In combination with field data, GIS and Landsat data are
being used to identify the patterns of ecosystem change
among the selected landforms and ecosystem types.
• The 14 test stands were mapped
and combined with other UMBS
GIS and Landsat data layers
Spectral-Temporal Remote Sensing
A combination of Landsat spectral and temporal (deciduous leaf-on/leaf-off) analysis
provides information on a) aspen dominated overstory and b) deciduous vs. coniferous
understory and successional pathway over the entire spatial extent of UMBS and region.
Creating an SNRE UMBS GIS
•Many other ArcGIS “layers” were
created as a result of this project - a
few are shown here overlaid on one
Landsat band.
•The entire UMBS GIS will
eventually be hosted on the
ESA Lab website.
Hydrology
Transportation
Landform Level Ecosystems
Conclusions
• Due to accelerating succession, aspen stands will be
replaced by later successional species depending upon
the site-specific ecosystem of their occurrence.
• Successional models based on the landscape
ecosystem framework will prove useful in determining
the spatial occurrence of the aspen resource, rate of
decline, and succession to other species at the regional
landscape scale.