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Range of Natural Variability PowerPoint Presentation by Pete Slide

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					Range of Natural Variability
                Pete Fulé
       Northern Arizona University

• What is RNV?
• RNV relates to … Ecosystem
  Management … Ecological Restoration …
  Conservation Biology
• Historical forest structure and function
  in the Southwest
           What is RNV?
• “A science of land health needs, first of
  all, a base datum of normality, a picture
  of how healthy land maintains itself as
  an organism.”     Aldo Leopold (1941)

• What is the “base datum”?

• Terms: range of natural variability,
  historical variability, reference
  conditions
“We define natural variability as the ecological
  conditions, and the spatial and temporal
  variation in these conditions, that are
  relatively unaffected by people, within a
  period of time and geographical area …”
           (Landres et al. (1999): Ecol. App. 9:1279-1288)

• “The (dynamic) conditions that would exist if
  the dominant Euro-American culture had
  never arrived, but Native Americans had
  continued to use the landscape.”
           (Stephenson (1999): Ecol. App. 9:1253-1265)
               Why care?
• Modern human impacts may diminish species
  viability.
• Coarse-filter management strategy conserves
  even poorly understood species.
• Fewer external subsidies when manage within
  bounds of system.
• Useful reference point for human-caused
  impacts.
• Analysis at long time frames & large scales.
• Recognizes importance of disturbance.
• Spatial heterogeneity important for resilience.
                       Landres et al. 1999
 RNV and Ecosystem Management
• Conservation of ecosystem structure,
  composition, and function across the full
  range of spatial and temporal scales:

  –   Think long term
  –   Save all the pieces
  –   Save all the processes
  –   Assure sustainability

                       Kaufmann et al. (1994)
                       Gen. Tech. Rep. RM-246
       Ecosystem Needs Assessment

Ecosystem Needs                   Analysis
  & Capabilities                   Area


                       Ecological
                       Principles
                       Applied at
 Fine Filter                            Reference
                      Appropriate
  Analysis                              Conditions
                        Spatial
                     And Temporal
                        Themes



    Coarse Filter                  Existing
      Analysis                    Conditions



               Kaufmann et al. 1994, Gen. Tech. Rep. RM-246
        Ecoregion   Subregion  
     Landscape   Watershed/Land Unit

• Air Quality         • Corridors
• Water Quality       • Travel Linkages
• Weather             • Species Viability
• Hydrology           • Fragmentation
• Aquatic Systems     • Habitat Relationships
• Geomorphic          • Insects & Pathogens
  Processes           • Nutrient/Soil
• Fire/Fuels Regime     Productivity
                      • Succession &
                        Community
  RNV and Ecosystem Management
• EM (and other management approaches) are not
  “science-based” but “science-informed.”
• RNV is fundamental to EM but is not necessarily the
  goal.
• In Ecological Restoration, the RNV can become the
  goal or target of a management action.
• But ER is a subset of EM (“tool in the toolbox”…).
• Ultimately our objective is not to pick some perfect
  management paradigm, but to continually improve
  and adapt management in an evolving relationship
  between ecological and social constraints and
  capabilities.
RNV and Ecological Restoration
• Ecological restoration is the process of
  assisting the recovery and management of
  ecological integrity. Ecological integrity
  includes a critical range of variability in
  biodiversity, ecological processes and
  structures, regional and historical context,
  and sustainable cultural practices” (Society
  for Ecological Restoration 1998).

• “Ecological restoration is the process of
  assisting the recovery of an ecosystem that
  has been degraded, damaged, or destroyed”
  (SER 2002).
Restoration shares many values with sustainable
  resource management, conservation biology, and
  land reclamation. Two distinguishing
  characteristics are:

(1) The use of intact, indigenous ecosystems as the
   point of reference;

(2) A focus usually at the scale of entire ecosystems.

Southwestern forest restoration traces its lineage to
  Aldo Leopold. Key studies were done by Harold
  Weaver (1940’s-50’s) and Charles Cooper (1950’s-
  60’s), as well as many other scientists and resource
  managers.
        Reference Conditions: Leopold’s “base datum”

1. Reconstruct past conditions through dendroecological,
paleoecological, or other historical ecology techniques.

2. Measure relatively undisturbed contemporary sites to
compare to reconstructed data and to explore the effects of
altered modern conditions such as high CO 2 levels.

3. Draw inferences from
ecological relationships
observed in disturbed
sites.

4. Restore ecological
conditions as a modern
model for observing
ecosystem function.
  Information on RNV: Multiple
       Lines of Evidence

• Information on RNV is often
  fragmentary, limited, incomplete.
• Make use of multiple lines of evidence.
• Always recognize limitations of the
  data.
Swetnam et al. 1999, Ecol. App. 9:1189-1206
    Historical Ecology Methods:
     Written & Oral Histories
• Written documents include historic
  forest inventories, scientific/military
  expeditions, colonial records, land
  surveys, diaries, missionaries.
• Photographs and maps.
• Oral histories may be available or you
  may develop an oral history to capture
  local knowledge.
     Written Histories & Photographs
• Goals and cultural filter
  of the historian.
• Propaganda and
  advertisement.
• Biases in scientific
  studies.
• Biases in forest
  inventories.
• Practical biases
  (selection of trees in
  land survey).
• All these factors also
  apply to maps and           Photo G. Pearson 1909, Grandview (Grand Can.)
  photographs.                Courtesy Rocky Mountain Research Station
Mt. Trumbull, Arizona: 1870
Moore et al. (1999), Ecol. App. 9:1266-1277.
Mt. Trumbull, Arizona: 1995
Moore et al. (1999), Ecol. App. 9:1266-1277.
                                                    Andrew Sanchez Meador




Logging near Cloudcroft from 1903, courtesy of the Rick Miller collection of
historic photos. There are historic Mixed Conifer plots in "Cox Canyon" (south
of Cloudcroft) and Douglas-Fir plots near (what is now) Pine Campground.
Detail of a forest plot mapped in 1915 by G. Pearson
and T. Woolsey, Fort Valley Experimental Forest, AZ
Check mark on Woolsey map represents a ponderosa pine seedling over 12“;
X with a line under it is a cut yellow pine stump.




    Andrew J. Meador
                                                    Andrew Sanchez Meador




Taos: several Woolsey plots around Taos, but most have not been found. Amole,
Gallegos, Cienaga, Osha Canyon, Rio Pueblo, La Junta, and numerous plots in
Angostura. This is a pine plot at Amole.
                         Andrew Sanchez Meador




Cienaga post-fire ingrowth.
   Written and Oral Histories
  Include Traditional Knowledge
• Native American sources
  – Kat Anderson, California tribes
  – Thom Alcoze, Kaibab Paiute & Cherokee
• Anthropological sources
  – Ranching, farming, logging practices
• Relationship between historical sources and
  archeological evidence
• Relationship between historical sources and
  ecological evidence
  – Population and fire in Mexico
  – Apache presence/cambial scars/fire in New Mexico
   Historical Ecology Methods:
         Dendroecology

• Application of dendrochronology
  (crossdating tree rings) to ecological
  questions.
• Dendrochronology invented in Flagstaff!
• Basics of dendrochronology
• Climate example
• Forest structure example
Laboratory of Tree-Ring Research, University of Arizona
Woodhouse & Bauer: World Data Center A
Woodhouse & Bauer: World Data Center A
  Reconstructing Forest Structure
      with Dendrochronology:
     Gus Pearson Natural Area
• Dendrochronology for tree age
• 100% sampling of dead trees
  – Test of reconstruction methods
  – Test of accuracy of restoration silviculture
• Mapping of all tree positions
• Age structure: RNV & target for
  restoration
• Age structure of groups: regeneration
  and fire patterns
      Assessing Age Structure for Ecological Restoration

                                       20




                             # Trees
                                       10
                                        0
                                       GPNA 1992



                                          45

                                          15

                                         85

                                         55

                                         25

                                         95
Mast et al (1999)


                                       15

                                       16

                                       16

                                       17

                                       18

                                       18
Ecol. App. 9:228-239

      6000
      4000
      2000
          0
                         65
                                  05




                                                       65
         45
               85
                    25




                                        45
                                             85
                                                  25


                                                            05
                                                                 45
                                                                      85
                        16




                                                      18
       15
              15
                   16




                                       17
                                            17
                                                 18


                                                           19
                                                                19
                                                                     19
                             17
                      1992 Age Frequency                      1994 Age Frequency                     1876 Age Frequency

            1.2

             1
Frequency




            0.8

            0.6

            0.4

            0.2

             0
                                      120




                                                                                                               480
                                                               240
                                                                     270




                                                                                                         450
                       30
                            60

                                 90




                                                  180




                                                                           300
                                                                                 330


                                                                                             390




                                                                                                                     510
                                                                                                                           540
                                            150


                                                        210




                                                                                       360


                                                                                                   420
                  0




                                                                Tree Age


                        Mast et al. 1999, Ecol. App. 9:228-239
      Restoring Spatial Structure of the Forest
  Changes in forest structure since 1876 at the
Gus Pearson Natural Area ecological restoration site




      1876
                               1992

                                      After Full Restoration
Covington et al. (1997)
Journal of Forestry 95:23-29
                           Restoration Techniques
   • Overstory trees: thinning, species composition,
       spatial pattern, old-growth.
   • Understory herbs and shrubs: natural
       regeneration, seeding, planting.
   • Fuels: accumulated fuels, canopy fuels, dead biomass
       as nutrient sources and habitat.
   • Fire: re-introducing fire, unique initial burn
       conditions, smoke.
   • Monitoring and adapting:                                         evaluating results and
       making changes.

Covington, W.W., P.Z. Fulé, M.M. Moore, S.C. Hart, T.E. Kolb, J.N. Mast, S.S. Sackett, and M.R. Wagner. 1997.
Restoration of ecosystem health in southwestern ponderosa pine forests. Journal of Forestry 95(4):23-29.

				
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