Range of Natural Variability

1
Range of Natural Variability Pete Fulé Norther
n Arizona University

• What is RNV?
• RNV relates to Ecosystem Management
  Ecological Restoration Conservation Biology
  
• Historical forest structure and function in the
  Southwest

2
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

3

• 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.
  91279-1288)
  
• 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. 91253-1265)

4
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

5
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

6
Ecosystem Needs Assessment
Ecological Principles Applied at Appropriate
Spatial
And Temporal Themes
Kaufmann et al. 1994, Gen. Tech. Rep. RM-246
7
Ecoregion ? ? Subregion ? ? Landscape ? ? Waters
hed/Land Unit

• Corridors
• Travel Linkages
• Species Viability
• Fragmentation
• Habitat Relationships
• Insects Pathogens
• Nutrient/Soil Productivity
• Succession Community

• Air Quality
• Water Quality
• Weather
• Hydrology
• Aquatic Systems
• Geomorphic Processes
• Fire/Fuels Regime

8
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.

9
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).

10

• Restoration shares many values with sustainable
  resource management, conservation biology, and
  land reclamation. Two distinguishing
  characteristics are
• 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 (1940s-50s) and Charles Cooper
  (1950s-60s), as well as many other scientists
  and resource managers.

11
Reference Conditions Leopolds base datum
1. Reconstruct past conditions through dendroeco
logical, paleoecological, or other historical
ecology techniques. 2. Measure relatively undis
turbed contemporary sites to compare to
reconstructed data and to explore the effects of
altered modern conditions such as high CO2
levels. 3. Draw inferences from ecological re
lationships observed in disturbed sites. 4
. Restore ecological conditions as a modern mo
del for observing ecosystem function.
12
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.

13
Swetnam et al. 1999, Ecol. App. 91189-1206
14
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.

15
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
  photographs.

Photo G. Pearson 1909, Grandview (Grand Can.)
Courtesy Rocky Mountain Research Station
16
Mt. Trumbull, Arizona 1870 Moore et al. (1999),
Ecol. App. 91266-1277.
17
Mt. Trumbull, Arizona 1995 Moore et al. (1999),
Ecol. App. 91266-1277.

18
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.
19
Detail of a forest plot mapped in 1915 by G.
Pearson and T. Woolsey, Fort Valley Experimental
Forest, AZ
20
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
21
Andrew Sanchez Meador
Taos several Woolsey plots around Taos, but most
have not been found. Amole, Gallegos, Cienaga, Os
ha Canyon, Rio Pueblo, La Junta, and numerous
plots in Angostura. This is a pine plot at Amole
.
22
Andrew Sanchez Meador
Cienaga post-fire ingrowth.
23
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

24
Historical Ecology MethodsDendroecology

• Application of dendrochronology (crossdating tree
  rings) to ecological questions.
  
• Dendrochronology invented in Flagstaff!
• Basics of dendrochronology
• Climate example
• Forest structure example

25
Laboratory of Tree-Ring Research, University of
Arizona
26
Woodhouse Bauer World Data Center A
27
Woodhouse Bauer World Data Center A
28
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

29
Assessing Age Structure for Ecological
Restoration
Mast et al (1999) Ecol. App. 9228-239
30
Mast et al. 1999, Ecol. App. 9228-239
31
Restoring Spatial Structure of the Forest
Covington et al. (1997) Journal of Forestry 9523
-29
32
(No Transcript)
33
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.