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Space, Relativity, and Uncertainty in Ecosystem Assessment of Everglades
Restoration Scenarios
Michael M. Fuller, Louis J. Gross,
Scott M. Duke-Sylvester, and Mark Palmer
Background and Need
General Approach to Scenario Comparison
Specific Example: Everglades Restudy Area
Multi-Species Approach
Methodology
Results of Analysis
Summary & Conclusions
Relative Assessment of Management Scenarios
Balancing the needs of multiple stakeholders
Policy decisions based on inputs from:
• Urban Resource Agencies (water districts, air quality depts, etc)• Farmers and Industry (fisheries, timber companies, etc).• Conservation Organizations (Audubon, NRDC, etc.)• Governing Bodies (municipal, county, state, federal - politcal)• Natural Area Managers (National Parks, etc)
Natural systems are complex; Uncertainty is highProblem:
Solution: use models to:
Better understand natural systems.
Test sensitivity of system to different variables.Forecast future state of system.
Models can have complex structure
EXAMPLE: SESI ModelAlligator & Everglades Hydrology
• Many potential sources of error
• Reproduction: nesting, mating
• Many parameters
• Spatially Explicit Species Index
• Several alternative hydrology plans
Evaluate variation in input data or parameter settings
Incorporate uncertainty into analyses using hypothetical data
SA used to rank alternative management plans.
Scenario Analysis
Predict effects of alternative management plans.
Investigate changes in conditions or environmental impacts.
Evaluate variation in input data or parameter settings
Incorporate uncertainty into analyses using hypothetical data
SA used to rank alternative management plans.
Scenario Analysis
PROJECT (forecast) effects of alternative management plans.
Investigate changes in conditions or environmental impacts.
SA assumes that interactions between model components, and error propagation, is similar for different scenarios,
Uncertainty in how models respond toalternative scenarios can expose policydecisions to unexpected system behavior.
How can we reduce uncertainty?
A tool for testing the assumptions about model behavior.
Relative Assessment
Does rank order of management plan change with different Input data or parameter scenarios?
Reduce uncertainty of model behavior
Comparison requires a specific assessment criterion
A metric for ranking alternatives in order of preference
Using relative assessment for Everglades Restoration
• Does rank order of alternatives change?
• Compare alternative hydrology plans under consideration.
• Scenario analysis used to rank alternatives
• Relative assessment to reduce uncertainty.
General Approach
• Vary the input data and parameter settings.
• Multi-species comparison.
Central and South Florida Project Comprehensive Review Study
Three natural areas in southern Florida:
Two management alternatives: F2050 & D13R
Study System
• Everglades National Park• Big Cypress• Restudy area
F2050 = Baseline
4 Species + 2 wading bird guilds
ATLSS Spatially Explicit Index Models
Study System
Assessment Criterion
Species and Geographic Subregions
Subregion Species Affected Subregion Description
R1American alligator
and Snail kiteWater Conservation areas 3A and 3B
R2 Snail kite Water Conservation areas 1, 2A, 2B
R3 American alligator Shark River, NE Shark River, and Taylor Sloughs
R4 Wading Birds Central Rookeries
R5 Wading Birds Southern Rookeries
R6 Cape Sable seaside sparrow Core area
R7 Cape Sable seaside sparrow Western area
R8 Cape Sable seaside sparrow Eastern area
R9 White- tailed deer Everglades National Park
R10 White- tailed deer Big Cypress
Constructing Alligator Nest Parameter Scenarios
x 100
Average SESI ValueRepeat for
each subregion
Spatially ExplicitHabitat Index
(SESI)
Repeat for each hydrology scenario (F2050 & D13R)
HydrologyScenario
GeographicSubregion
SESI Model
Test Values
30 years of Historic Water Levels
Change values ±20 percent
9 nesting parameters
Baseline Values
Average over space & time
Constructing Climate I Data
30 year historic base pattern
Select 5 wettest years
Randomly reorder selected years
Repeat 5 more times
Combine into 30 year sequence
Repeat 27 more times
Calculate a mean SESI value for each 30 year sequence, for eachhydrologic plan, and a global mean for eachplan.
1
2
28
Calculate a differencein global means. -0.0428
D13R F2050
0.13660.13660.1367
0.1366
0.15350.15340.1534
0.1535
123
28
Count
Hydrologic Plan
Long Wading Bird SESI
0.2291 0.2719Grand Mean
All species groups.
Criterion: SESI Value
Difference between F2050 & D13R
Average over space & time
Constructing Climate II Data
Simulate 30 years of water level data.
1) Increase rainfall by 25 percent
2) Decrease rainfall by 25 percent
Baseline Data: 30 year historic pattern.
Experimental Data
Comparison for all species groups.
Criterion: SESI Value
Difference between F2050 & D13R D = F2050 - D13R
Summary of Scenarios and Treatments
Scenario Taxon Treatment
Nesting Parameter
VariationAlligator
Parameters randomly changed in the range of ±20% and
±30% of standard settings.
Climate Change I All 6 TaxaResampling and permutation of historical climate data to
create 3 climate themes: wet, dry, and average climate.
Climate Change II All 6 Taxa Baseline ±25 percent random variation in water levels.
Effect of Random Variation in Model Parameters30 Percent Variation
Difference between Alternative Scenarios (SESI)
20 Percent Variation
R1 R1
R3
10
20
30
40
10
20
30
40
.026 .028 .030 .032 .034 .036 .038
R1 = Water conservation areas 3A and 3B
R3 = Shark river, NE Shark river, and Taylor slough
No rank reversals
D = F2050 - D13R
Climate Change Effects
Difference between F2050 & D13RCriterion: SESI Value
D = 0 (No difference)
Baseline
Increase level
D = F2050 - D13RD13RF2050
Decrease level
For each species:D < 0D > 0
Effect of Simulated Climate on Scenario Ranking
Difference in SESI (D13R - F2050)
White-TailedDeer
AmericanAlligator Snail Kite
Cape Sable Seaside Sparrow
Long-LeggedWading Birds
Short-LeggedWading Birds
Effect of Simulated Climate Shift on Scenario Ranking
Difference in SESI (D13R - F2050)
White-TailedDeer
AmericanAlligator Snail Kite
Cape SableSeaside Sparrow
Long-LeggedWading Birds
Short-LeggedWading Birds
Summary of Effect on Rank Order of Hydrologic Scenarios
Taxon Scenario Type
Percent of scenarios
that rank
F2050 > D13R
Percent of scenarios that reverse
the rank order of F2050 & D13R
relative to base scenario.
Alligator ≤20% Parameter Variation None None
Alligator ≤30% Parameter Variation None None
All Ta xa Climate Change I 54.17% 25.93%
All Ta xa Climate Change II 53.71% 30.55%
Substantial variation in parameters = no reversals in rank order
Substantial variation in rainfall pattern = reversals in rank order
American Alligator
All Species Groups
Recap
• Compare rank order of alternatives.
• Compare alternative hydrology plans.
• Scenario analysis useful for ranking alternatives
• Relative assessment helps reduce uncertainty.
Summary
• Construct hypothetical climate patterns from historic data.
General Approach
• Change in climate patterns caused some rank reversals.• Alligator SESI not affected by parameter variation
Results
• Randomly vary nesting parameters (alligator).