Landscape Modeling for Blue Wing Teal in the Sheboygan River Basin: A Weighted Criterion Approach C. Pekar, October 1, 2009 Advisor: Dr. Todd Bacastow.

Landscape Modeling for Blue Wing Teal in the Sheboygan

River Basin: A Weighted Criterion

Approach

C. Pekar, October 1, 2009Advisor: Dr. Todd Bacastow

Overview

• The Problem of Weighting Criteria

•Discussion of Analytic Hierarchy Process

•Discussion of Sheboygan River Basin, Wetland Restoration and Blue Wing Teal

•Review of Related Projects

•Proposed Project Sequence

Traditional GIS- based site selection processes often fail to assign weights to input criteria layers.

Problem

1 0 1

2 1 0

2 0 0

1 0 0

1 2 1

1 2 1

2 0 1

3 3 1

3 2 1

Layer 1

Layer 2

OutputLayer

+

=

Vs.

1 0 1

2 1 0

2 0 0

1 0 0

1 2 1

1 2 1

1 0 .25

1.25 1.75 .75

1.25 1.5 .75

Layer 1(.25)

Layer 2(.75)

OutputLayer

+

=

The Analytic Hierarchy Process creates a framework which ascribes numerical weightings to subjective preferences.

Solution

What does it do?It allows users to break down complex problems into a hierarchy of a goal and subordinate features .

How does it relate to GIS?AHP can be used to determine the weights of different data layers

(criteria) used in a raster-based site-selection analysis.

How are the weights determined?One of the cornerstones of the AHP is the “pairwise comparison” of every

combination of criteria using the “Fundamental Scale of Absolute Numbers”.

This is performed by an expert panel. The results are imported into a matrix and from which the weights are derived.

Traditional depiction of AHP.

Goal

Criteria 2 Criteria 1 Criteria 4 Criteria 3

Alt. 1 Alt. 2 Alt. 3

Fundamental Scale of Absolute Numbers

Intensity of Importance

Definition Explanation

1 Equal Importance Two criteria contribute equally to the objective

3 Moderate Importance Experience and judgment slightly favor one criteria over another

5 Strong Importance Exp. and judgment strongly favor one criteria over another

7 Very Strong Importance

One criteria is strongly favored over another

9 Extreme Importance The evidence favoring one criteria over another is of the highest possible order of affirmation

2, 4, 6, 8 Intermediate Values

Reciprocals of Above

Values for Inverse Comparison

Adapted from Saaty, 2005 and Marinoni, 2004

Example Pairwise Comparison Matrix – Identifying Suitable Sites for Gravel Pits

Adapted from Marinoni, 2006

WPZ Dist Over-burden

Thick-ness

Soil Prod.

WPZ 1 1/4 5 5 1/2

Dist 4 1 7 7 4

Over-burden

1/5 1/7 1 1/4 1/5

Thick-ness

1/5 1/7 4 1 1/7

Soil Prod.

2 1/4 5 7 1

WPZ = Water Protection ZoneDist = Distance to Settlements (m)Overburden = Thickness of Overburden (m)Thickness = Thickness of Desired MaterialSoil Prod. = Agricultural Productivity of Soils

Establishing Criteria Weights – (Doing the Math!)

From Nekhay, Arriaza and Guzman-Alvarez, 2008

n = criteriaw = comparison scores (1-9)

On Consistency

Criteria 2 Criteria 1

Criteria 3

The Consistency Ratio provides a measure to ensure consistency exists amongst the criterion weightings.

Example of Resulting Suitability Map – Evaluation of Iberian Lynx Habitat Restoration Potential for Olive Groves in Southern Spain

From Nekhay and Arriaza, 2009

How does this fit into organizational decision making?

“…the Spatial Decision Support System itself is not a decision maker. Its purpose is to give recommendations to the

decision makers.” (Marinoni and Hoppe, 2006)

Other Concerns – Group Dynamics• Scheduling Conflicts• Groupthink• Dominant Voice• “Comparison Fatigue”

Why Potentially Restorable Wetlands in the Sheboygan

River Basin?

Historic Statewide Wetland LossOver 50% of the wetlands in the state have been lost since European settlement.

EPA Area of Concern•Legal designation by USEPA for the most polluted waterways in Great Lakes Region•32 of the 35 are in the U.S.•Our best opportunity for restoring the health of the Great Lakes is to recover the ecological services of these river basins and get them de-listed (clean).

Why the Intent on Improving Blue Wing Teal Breeding

Habitat?

From Wisconsin DNR

Population DeclineWhile other waterfowl populations in Wisconsin have stabilized or are increasing, the Blue Wing Teal population is still trending downwards.

From Wisconsin DNR

Also, the Blue Wing Teal is considered a Focal Species by the Upper Mississippi River and Great Lakes Region Joint Venture.

Conservation StatusThe Blue Wing Teal is listed as a Wisconsin Species of Greatest Conservation Need by the Wisconsin Department of Natural Resources.

Related Projects

Milwaukee River Basin Wetland Assessment Project•Vector-based analysis created Potentially Restorable Wetland layer for the Milwaukee River Basin.•Input layers limited to NRCS soil units, WI Wetland Inventory, and WiscLAND Landcover.

Sheboygan River Basin Conservation Mapping Tool•Raster-based analysis using watersheds and sub-watersheds as the unit level of analysis within the Sheboygan River Basin.•Ranked watersheds and sub-watersheds according to criteria such as Migratory Bird Habitat Model, Natural Landcover, Percent of Sub-watershed that is Wetland, and Percent of Sub-watershed with Potentially Restorable Wetlands.•“With some GIS expertise, there are numerous data combinations and score ‘weighting’ that could be done with the mapping tool to customize the prioritization of sub-watersheds”.

1. Communicate goal to stakeholders.2. Identify 15-20 potential criteria layers.3. Determine up to 10 criteria layers with subgroup of expert panel.4. Determine values for intra-layer alternatives with subgroup of expert

panel.5. Present criteria and values to expert panel for acceptance.6. Make any revisions to criteria or scoring of intra-layer alternatives.7. Reclassify data layers to reflect determined values and import layers

into the GIS.8. Email survey with “pairwise comparisons” to expert panel.9. Average results from survey and execute preliminary analysis to

calculate criteria layer weightings and determine Consistency Ratio.10. Present weightings and Consistency Ratio to expert panel for

acceptance.11. Make any revisions as necessary.12. Finalize analysis and create suitability mapping.13. Identify highest ranking sites for further analysis and field

evaluation.14. Compare Primary Output Map with 1) unweighted version of output

map and 2) baseline PRW layer

Proposed Process

Functional Wetland Restoration Layers•Soils•Slope•WI Wetland Inventory•Landcover•Proximity to Waterbodies•Ditches •Reed Canary Grass

Teal Specific Layers•Migratory Bird Stopover Model (by subwatershed)•Historic Wetland Loss (by subwatershed)•Percent Grassland (by subwatershed)•Percent Wetland (by subwatershed)•Percent Forest (by subwatershed)•Distance from Forested Tracts•Known Breeding Occurrences of Blue Wing Teal

Potential Search Criteria

• October • Finalize Criteria• Prepare Survey• Acquire Remaining Data Layers• Submit Conference Abstract

• November• Present Criteria to Expert Panel• Distribute Survey• Reclassify Raster Data• Collect Survey Data and Determine Weights/Verify Consistency

Index• Present Weightings and Consistency Ratio to Panel for Acceptance

• December• Begin Analysis

• January• Complete Analysis• Complete Draft Report

• February• Finalize Report and Present Findings to Expert Panel

• March• Present Paper at American Water Resources Association Conference

Project Timeline

How Could this Possibly Go Wrong?

Concern Safety Valve

Lack of Consensus on Criteria?

Short-list of Experts Determining Criteria

Scheduling Conflict? Surveys to be Delivered Electronically

Experts Uncomfortable with Resulting Weightings?

Opportunity to Modify Pairwise Rankings

Questions?

From Wisconsin DNR