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					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
                       80.0                                                                                        Subdominant Overstory
                                                                                                                   SubdominantOverstory
                                                                                                                   Understory
                                                                                                                    Understory
                       70.0

                       60.0
Relative Density (%)




                       50.0

                       40.0

                       30.0

                       20.0

                       10.0

                        0.0
                                   1            4           24          25            36           37         41           42          44           45
                                Low-elevation outwash Low-elevation outwash       High-elevation severely   High-elevation banded   High-elevation calcareous
                                   (Pellston Plain)   wetlands (Pellston Plain)    burned outwash plain         outwash plain            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
                     350                                                                          Understory

                     300
Density (stems/ha)




                     250

                     200

                     150

                     100

                     50

                       0
                               1     36     37     74     44     45     40      59    60     76       77       96+97
                                                               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.
                   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.

				
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posted:10/19/2012
language:English
pages:15