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Maura OlivosSalt Lake Community College GEOG 2900 – A. DastrupApril 30, 2012

Alta Ski Area Vegetation Communities – A Predictive Analysis Map

Independent Study Update

This project was pursued with the intent to “help guide both the Forest Service and the ski industry in maintaining, restoring and managing sensitive alpine environments and national forests for continued sustainable commerce of our national lands.”1 This consisted of identifying appropriate data for analysis, performing a series of geoprocessing tools, displaying the output in a visually appealing map, and most importantly identifying the relevant use and additional steps to refine the data. Much of the projects steps diverted from the original proposal, but the outcome is believed to be of higher quality than if the originally intended data sources were used for analysis. The remainder of this update details the methodology, results, next steps and project reflection.

Methodology

Data Acquisition: The data used for this analysis was completed with four different resources than originally planned.

1. As mentioned in the February 15, 2012 project proposal, ASA was just starting its GIS program with the process of georeferencing CAD files for GIS use and acquiring appropriate DEMs. From this contracted work Alta was supplied with the slope, aspect and elevation topographic files, vector line and polygon files, as well as a georeferenced aerial image rasters for this analysis.

2. Completed in December 2012, the original 1997 “Vegetation Communities Map” from the Final EIS –Alta Ski Area Master Development Plan was georeferenced. The re-creation of that map’s features was completed to act as a guideline in identifying each plant community type’s defining attributes.

3. The Town of Alta was the third party source for viable vector data, including: structures, contour lines, roads, lifts, and mountain summits.

4. Lastly, polygon shapes were drawn to identify true locations of different plant community types based from ASA’s Vegetation Management Plan study plot point data.

Data Analysis: This analysis of the data was the bulk of this project and took a long series of trial and errors in determining the best geoprocessing tools for the desired and workable output. The following includes the basic steps for each plant community type. For detailed notes please see attached “Geoprocessing Steps and Notes.”

1. Define classification fields for slope, aspect and elevation.2. Prepare vector data, included connecting polylines to convert to polygons3. Identify defining attributes for each vegetation type, includes: vector similarities, slope, aspect and

elevation.4. Perform a binary spatial analysis with geoprocessing tool “Raster Calculator” for slope, aspect and

elevation.5. Select Binary Output “1” to create a new layer and convert “Raster to Polygon.”

1 “A Proposal for GIS Independent Study”, Maura Olivos, February 15, 2012.

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6. “Intersect” or “Erase” new polygon layer with other appropriate polygon attributes to reach final plant community type.

Deliverables & Results

Most of the deliverables of this project were met with the following (detailed from original proposal) and can all be found at this site - http://olivosgisportfolio.yolasite.com. Uncompleted portions are colored in red.

1. A georeferenced version of ASA’s “Vegetation Management Plan” management boundaries in the form a vector file, including appropriate attributes and metadata.

2. A georeferenced version of ASA’s “Vegetation Types” boundaries in the form of a vector file, including appropriate attributes and metadata.

3. An updated version of the “Vegetation Types” map with predictive analysis providing vegetation designations for disturbed ground within ASA to guide restoration efforts in the form of a vector file with appropriate attributes and metadata, and an analysis outline.

4. Map and paper describing the findings and potential applications of this project.

Next Steps

The symbology of the final map for this project was manipulated to show a finished product, but to allow for usable data for greater purposes the actual data files still need refinement. The following includes the next appropriate steps to allow for a sharable dataset.

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1. Share a five-layer map (aerial image, predictive output, elevation, slope and aspect) with other certified Ecologists and Botanist for third party verification of the predictive analysis.

2. Refine Vegetation Type data layers, includes:a. Merging or dissolving overlapping polygons of the same vegetation type. b. Editing attribute tables c. Permanently joining all vegetation types into a single feature class.

3. Edit anomalies within the predictive model and make note4. Determine whether a model can be made and performed.

Once these steps are completed the project will have received appropriate verification for use and diffusion with other ski areas or micro-management of alpine ecosystems throughout the west.

Project Reflection

This project was much more complicated than originally thought, however I believe the visual output is of high quality and follows true to the predictive model with minor editing. In the beginning of this process the steps were elongated due to the unknown viability of the output. Once output was confirmed, then I became more comfortable with compiling data commands in single queries (versus a series of individual feature selection queries). Once other ecologists confirm the data, a lot of time will additionally be needed to edit the features so they output in a usable format with the attribute table. At first, I was very uncomfortable with not being able to completely finish the data editing, but then I received the opportunity to hear from a guest GIS professional “Buck” in my “Maps and Measurements” course. His comment was that the refinement of a map’s data can take up to 10 years, considering the verification, continued field trips, and collaboration, which is how long he and his team had been working on the maps that he shared with us. I feel much better knowing that though geoprocessing analysis can take a relatively short amount of time, verifying the data and editing it so that it is in a usable format can take a significant amount of collaboration and time.

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Geoprocessing Steps and Notes

1. Prepared Dataa. Vector Data for Selection

i. Treesii. Plant Comm 2011

iii. Wetlandsiv. Albion Wetlandsv. Land Cover

vi. AltaPavedRoadsb. Raster Data for Selection: Classified DEMs to appropriate needs

i. Slopeii. Aspect

iii. Elevationc. Conversions

i. Tree_Vegetation polyline to polygons (ArcToolbox > Data Management Tools > Features > Feature to Polygon)

ii. Edited AltaPavedRoads to close polylines then converted to polygons (Alta Paved Areas) – to be used as an erase feature

iii. Did not do the same with dirt roads because layer is not updated and falls under the potential predictive model since they are not permanent.

2. Created Control Vegetation sites to determine criteria for each plant community type (slope, elevation, aspect, etc.)

3. Conifer Willowa. Attributes

i. Trees & wetlands (no intermittent wetlands) must be presentii. Slope 0 – 30

iii. Aspect – alliv. Elevation – all

v.vi. Queries:

1. Performed a Binary Spatial Analyst to determine Initial criteria for slope and aspect

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2. Raster Calculator: input - slope_degree <= 30 / output – 1 or 30DegLess (raster)3. Intersect: Geoprocessing > Intersect – Input: Trees and Intermittent Wetlands /

output: WetTrees4. Convert Raster Data to Polygons: input - 30DegLess (raster) / output – 30deg

(polygons)5. Selection by Attribute: 30deg – Gridcode = 1 > make selection into a layer6. Intersect: Geoprocessing > Intersect – Input: WetTrees and 30deg / output:

ConiferWillow4. Alpine Forb: General description

i. Attributes1. No trees & wetlands2. Present in Rock Talus & Alpine Forb 3. Slope: 10-404. Aspects: all but S & SW5. Elevation: 10400 ft or more

ii. Queries1. Rock Talus & Alpine Forb > Selected from Plant_Comm_2011 and made into a

new layer2. Erase Analysis: Input – New Rock Talus-Alpine, Erase – Wetland and Trees3. Elevation: Raster Calculator input >=10400 ft / output 10400ft (Binary 1)4. Raster to Polygon: Input 10400ft / Output 10400ft5. Selected 9800 ft and less to use for Erase feature6. Raster Calculator: (Slope>=10) & (Slope <= 40) 7. Raster Calculator: (Aspect >= 157) & (Aspect <= 247), but worked with output 08. Raster to Polygon: Both Slope and Aspect outputs9. Select appropriate Grid Codes and Intersect Slope and Aspect10. Intersect SlopeAspect with RockTalus-AlpineForb for final AlpineForb layer

5. Short Forb: General Descriptioni. Attributes:

1. No trees & wetlands2. Acceptable parameters: Rock Talus and Short Forb3. Slope: 0-404. Aspects: No W, NW, N

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5. Elevation: max 10400ii. Queries:

1. Raster Calculator: ("slope_degree" <= 40) & ("elevation" < 10400) & ("aspect" >= 22) & ("aspect" <= 247)

2. Convert Raster to Polygon3. Erase from new polygon: trees, wetlands, conifer willow, alpine forb4. A lot of overlap with potential other plant community types, must come back to

later after more has been narrowed down.5.

6. Tall Forb: This plant community type can exist with many other specific community characteristics. Attempt will be made to identify generals then overlapping areas with other plant community will be separated out.

i. Attributes1. No rock/talus, no glacial polish rock2. Acceptable overlap: Intermittent wetlands, trees, wetlands3. Slope: 0-304. Aspect: No S5. Elevation: max 10200 / True tall Forb 9800

ii. Queries:1. Raster Calculation: ("slope_degree" <= 30) & ("elevation" <= 3109) & ("aspect"

<= 157) 2. Raster Calculator: ("slope_degree" <= 30) & ("elevation" <= 3109) & ("aspect" >=

202)3. Raster to Polygon4. Select output 1 and merge to “PossibleTallForb”areas (use for following)

iii. Tall Forb Variety Queries1. Intersect: Tall Forb + Intermittent Wetlands + Trees (erase ConiferWillow) =

ConiferWillowTallForb2. Intersect: Tall Forb + Trees = ConiferTallForb3. Tall Forb Possible and Erase: ConiferWillowTallForb and ConiferTallForb4. Intersect: Tall Forb + Intermittent Wetlands = Tall ForbWillow5. Conifer/Tall Forb > Must Select out the known areas of Aspen for Aspen/Tall

Forb6. Raster Calculator: ("elevation" >= 3109) & ("aspect" >= 202) & ("slope_degree"

>= 25) & ("slope_degree" <= 40)= ShrubTall ForbPotentiala. Convert raster to polygonb. Select gride code = 1 and make selection into layerc. Erase all layers that apply to narrow area occurrence

7. Conifer/Shrubi. Attributes: Are the presence of all trees

ii. Queries1. Trees Erase (ConiferWillow, ConiferWillowTallForb, ConiferTallForb)

8. New Data to add to ASA Geodatabase• Tree_Vegetation2: Vector, polygon – converted polyline of Tree_Vegetation• AltaPavedAreas: Vector, polygon – completed (closed lines) and converted polyline of paved areas

in Alta to a polygon file

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• Forest Management Zones: Vector, polygon – georeferenced 1995 hand-drawn map• Plant Comm_1997: Vector, polygon – georeferenced 1995 hand-drawn plant community type areas• Plant_Comm_2011: Vector, polygon – 2011 minor update of 1995 data• Plant Community Types: Vector polygon – spatial analysis process

o Conifer Willowo Alpine Forbo Short Forbo Tall Forbo Willow-Tall Forbo Conifer-Tall Forbo Conifer Willowo Conifer-Willow-Tall Forbo Conifer – Shrubo Shrub – Tall Frobo Scree, Cliffs, Glacial Bedrock and Krumholz