Historical
Landscapes and
Legacies
Lisa A. Schulte
Department of Forest Ecology and
Management
University of Wisconsin-Madison
Why study historical landscapes?
(from Delcourt et al. 1983)
Human
Scale
Human
Scale
(from Bissonnette 1997)
Why study historical landscapes?
1) Broad-scale ecosystem processes can be slow and/or
infrequent.
Why study historical landscapes?
1) Ecosystem processes can be slow and/or infrequent.
2) To improve our understanding of ecosystem stability and
resilience – natural variability.
Ecological Stability and Resilience
Ecosystems:
• closed vs. open
• deterministic vs. stochastic
• homogeneous vs. heterogeneous
Natural Variability
• Understanding and maintaining dynamic ecosystems.
• Spatial and temporal variation in ecological conditions, that are
relatively unaffected by people, within a period of time and over
a geographical area (Landres et al. 1999).
• Assumptions:
1) Disturbance is an natural part of any ecosystem,
2) Ecosystems are resilient to disturbance,
3) Maintaining ecosystem types maintains ecosystem
integrity, over broad spatial scales.
Why study historical landscapes?
1) Ecosystem processes can be slow and/or infrequent.
2) To improve our understanding of ecosystem stability and
resilience.
3) To improve our predictions of future ecosystem states.
Complex Systems Theory
•
Ecological systems are complex and often dependent on
initial conditions.
•
Legacies – structures that affect ecosystem functioning long
after disturbance event.
Message from a Mountain
-- Franklin and MacMahon (2000)
Ecosystem
Recovery
Extant Theory Predicted
Actually Occurred
• Slow
• Uniform encroachment
by hardy species
• Ecological Succession
• Rapid
• Via diverse pathways:
largely nucleation
• Largely due to legacies
Biotic Legacies – the types, quantities, or patterns of organisms
and biotic structures that persist from the pre-disturbance
ecosystem.
Biotic Legacies of Mt. St. Helens:
Biotic Legacies – the types, quantities, or patterns of organisms
and biotic structures that persist from the pre-disturbance
ecosystem.
Biotic Legacies of Mt. St. Helens:
• rhizomes, roots, seeds, and spores
below ground
• pocket gophers and deer mice below
ground
• tree saplings and shrubs below snow
• invertebrates and amphibians in ponds
• snags and downed logs
Abiotic Legacies – physical modifications of the environment that
may result from disturbance.
Abiotic Legacies of Mt. St. Helens:
Abiotic Legacies – physical modifications of the environment that
may result from disturbance.
Abiotic Legacies of Mt. St. Helens:
• ash deposition
• mud slides and erosion channels
Why study historical landscapes?
1) Ecosystem processes can be slow and/or infrequent.
2) To improve our understanding of ecosystem stability and
resilience.
3) To improve our predictions of future ecosystem states.
4) To provide background for natural resources management
decisions.
Ecological Restoration
•
Requires defensible baselines.
•
Baselines are used to:
1) assess the need for restorative
treatments, and
2) to evaluate their success.
Why study historical landscapes?
1) Ecosystem processes can be slow and/or infrequent.
2) To improve our understanding of ecosystem stability and
resilience.
3) To improve our predictions of future ecosystem states.
4) To provide background for natural resources management
decisions.
5) General interested in where we have been.
Ways to Study Historical Landscapes
• The Environmental Record
• Lake Sediments, Bogs, Forest Hollows
• Tree Cores
• Packrat middens
• Field evidence
• The Written Record
• Land Surveys, Wills, Tax Rolls
• Aerial Photos, Maps, Landscape Photos
• Laws, Diaries, Artwork
Ways to Study Historical Landscapes
• Lake Sediments, Bogs, Forest Hollows
Palynology – species, not communities, migrate (Davis 1981)
Ways to Study Historical Landscapes
• Tree Cores
Dendrochronology –
Southwestern fire regimes
(Swetnam and Baisan 1996)
• Southwestern Ponderosa
Pine experience high
frequency, low intensity
fires
• High intensity stand
replacing fires rare
• Fire frequency climate
driven
• Fire suppression
coincided with AngloAmerican settlement
Ways to Study Historical Landscapes
• Packrat middens
Packrats middens –
vegetation migration along elevation gradients (Thompson 1990)
Ways to Study Historical Landscapes
• Field evidence
Ways to Study Historical Landscapes
• Land Surveys, Wills,
Tax Rolls
#
Quarter corner
6 miles
1W
Range
1E
Township 48 N
Section corner
#
Meander corner
#
1 mile
4th Principal meridian
Township 1 N
Baseline
Land Surveys – some uses and insights…
• Determining the ecological niche of tree species (Whitney 1982)
• Determine fire regime in even-aged systems (Radeloff et al.
1999)
• Baseline in documenting land cover change (White and
Mladenoff 1996)
• Baseline for ecological restoration (Parker 1997)
Ways to Study Historical Landscapes
• Aerial Photos, Maps, Landscape Photos
Maps, Aerial Photos – White and Mladenoff (1994)
Presettlement (1860s) – Public Land Surveys
Process: Broad-scale
human disturbance
Post-settlement (1930s) – Wisconsin Land
Economic Inventory
Process: Forest
succession
Current (1989) – Color infrared Aerial photos
Ways to Study Historical Landscapes
• Laws, Diaries, Artwork
“The soils is a red loam,
supporting a heavy forest of oak,
pine, hickory, and maple, and
interspersed with occasional
patches of highland prairie.”
--Henry Rowe Schoolcraft’s
description of the lower Fox River in
Wisconsin.
Artwork -- Mt. Trumbull, AZ
(Moore et al. 1999)
1870 sketch by artist,
H.H. Nichols
Mid-1990s photograph
All Data Sources have Strengths and
Limitations!!!
• Environmental Record
•Pollen of some species over/under represented due to
differences in dispersal or preservation.
•Extreme events can erase a previously recorded event.
• Written Record
•Bias or self-interest of observer.
•Knowledge of the observer.
•Context of the statement.
Multi-data Source
•
Moore, et al. (1999) use historical data to determine
reference conditions in Southwestern Ponderosa Pine
Forests:
Fire regime
Dendrochronology
Vegetation composition
Pollen Data
Vegetation structure
Dendrochronology,
Historical records & photos
Pack rats
All Data Sources have Strengths and
Limitations!!!
P = f (Production, Dispersal, Preservation, Identification)
Some important things we have
learned studying historical landscapes
• Ecosystems are NOT static, deterministic, homogenous, or
closed.
• Species, not communities, migrate latitudinally and elevationally
with climate change.
• Biotic and abiotic legacies from disturbances can have prolonged
effects on ecosystem composition, function, and structure.
• Human land use can have large and persistent affects on
vegetation patterning and stream quality.
• Reconstruct disturbance regimes.
• And much, much more….
Climatologists
Ecologists
Historians
Historical
Ecology
Landscape
Architects
Managers
Geographers
References
Davis, M. B. 1981. Quaternary history and the stability of forest communities. Pages 132 – 153
in West, D. C., H. H. Shugart, and D. B. Botkin, editors. Forest Succession. SpringerVerlag, New York, New York, USA.
Bissonette, J.A. 1997. Wildlife and landscape ecology. Springer, New York, New York, USA.
Delcourt, H. R., P. A. Delcourt, and T. Webb. 1983. Dynamic plant ecology: the spectrum of
vegetation change in space and time. Quaternary Science Review 1:153-175.
Egan, D., and E.A. Howell. 2001. The historical ecology handbook: a restorationist’s guide to
reference ecosystems. Island Press, Washington, D.C., USA.
Franklin, J.F., and J.A. MacMahon. Messages from a mountain. Science 288:1183-1184.
Landres, P. B., P. Morgan, and F. J. Swanson. 1999. Overview of the use of natural variability
concepts in managing ecological systems. Ecological Applications 9:1179-1188.
Moore, M.M., W.W. Covington, and P.Z. Fule. 1999. Reference conditions and ecological
restoration: a southwestern ponerosa pine perspective. Ecological Applications 9;12661277.
References (cont.)
Parker, L. 1997. Restaging an evolutionary drama: thinking big on the Chequamegon and Nicolet
National Forests. Pages 218-219 in Kohm, K.A., and J.F. Franklin, editors. Creating a
forestry for the 21st century: the science of ecosystem management. Island Press,
Washington, DC, USA.
Radeloff, V. C., D. J. Mladenoff, H. S. He, and M. S. Boyce. 1999. Forest landscape change: The
northwest Wisconsin Pine Barrens before European settlement and today. Canadian Journal
of Forest Research 29:1649-1659.
Russell, E.W.B. 1997. People and the land through time: linking ecology and history. Yale
University Press, New Haven, Connecticut, USA.
Thompson, R.S. 1990. Late Quaternary vegetation and climate in the Great Basin Pages 200239 in Betancourt, J.L., T.R. Van Devender, and PS. Martin, editors. Packrat middens: the
last 40,000 years of biotic chance. University of Arizona press, Tucson, Arizona, USA.
White, M.A., and D.J. Mladenoff. 1994. Old-growth forest landscape transitions from preEuropean settlement to present. Landscape Ecology 9:191-205.
Whitney, G. G. 1982. Vegetation-site relationships in the presettlement forests of northeastern
Ohio. Botanical Gazette 143:225-237.