· Web viewThis will create a new layer within the original name plus the word "selection": This new layer is a temporary selection layer that will vanish if you close your .mxd

FNR 65 Lab 8Music Festival, Part 2 – Spatial Analysis

Introduction

With the data in hand, we can now determine the optimal area to hold a Music Festival. We have been informed that the parcel(s) must be Rural Residential, zoned as " U," intersect with roads, avoid wetlands and rivers, and be within the range of a cell phone tower!

Learning Outcomes

Use basic vector analysis tools (Intersect, Buffer, Clip, Dissolve, Erase, Add Field, Field Properties, Add Field Type, BOOLEAN Operators, Delete Field, Select by Location, Field Calculator)

Perform basic overlay operations (Use Boolean operators to select features, Create a new layer from selected features, Export selected features to a new shapefile)

Create maps that convey results of spatial analysis

Walk Through

Within the Parcels shapefile, there are polygons that have been categorized as Rural Residential. In order to only select these polygons, we must use the Select by Attributes tool within ArcMap.

1. Launch the .mxd created in Lab 7:

2. From Table of Contents, right-click on Parcels and click on "Open Attribute Table:"


3. Within the Attribute Table, select "Table Options:"

4. From the drop-down menu, click on Select by Attributes:

5. This next step will bring up a Select By Attributes window. Click on "Help" near the bottom of the window and take a moment to read through the help documentation. Once you are done, close the Help window.

1. Double-click on "EXLU4" within the box under Method (notice that "EXLU4" appears in the box at the bottom), then click on Get Unique Values.

2. Get Unique Values will populate all unique values within EXLU4 within the middle box.

3. Click on the equal sign ("=").4. Double-click on 'rural residential' (notice again that this will appear in the box at

the bottom).


5. Once you are done (your window should look exactly as depicted below), click on Apply and all fields that match this description should highlight within the Attribute Table:

6. Click on "Show selected records" at the bottom of the window to only view selected records within the Attribute Table:


7. Right-click on Parcels and highlight "Selection" with your mouse from the drop-down menu. A new drop-down menu will appear adjacent to the one already open; click on "Create Layer From Selected Features" within this menu:


This will create a new layer within the original name plus the word "selection":

This new layer is a temporary selection layer that will vanish if you close your .mxd without saving. It is a representation of the data based on the original shapefile, so it must be exported as a shapefile in order to make this selection permanent.

8. Right-click on the "selection" layer and highlight "Data;" this will open a drop-down menu adjacent to the one already open. Click on "Export Data..." from this menu:


9. Export "all features," use the same coordinate system as "this layer's source data," and click on the folder icon to navigate to your 02_Working folder to save this selection as a shapefile:


10. Click OK and add the exported data to the map as a layer.

11. Within the Tools Toolbar above the Table of Contents, click on "Clear Selected Features" on the toolbar:

Skill Drill 1: Select by Attributes

11. Repeat the preceding steps, but for the Zone shapefile and Select by Attributes for all 'U' within "ZONING."

Do not query the ' U' at the top of the list (it has an extra space at the beginning), as this will give you the incorrect result. You should come up with 560 selections:

12. Remove the temporary layers from the Table of Contents so they are not confused with your new shapefile layers.

13. Click on the Geoprocessing tab and click on Intersect from the drop-down menu:


By using the Intersect tool on the Zoning and Parcels selection shapefiles, you are producing a shapefile that contains an Attribute Table that has all instances where a polygon is both 'U' and 'Rural Residential.'

13. Take a moment to read the Help documentation on this tool.14. For "Output Feature Class," navigate to your 02_Working folder by clicking on the folder

icon and saving your output shapefile as "RuralU.shp:"


15. Click on the "Selection" tab and click on Select By Location from the drop-down menu:


16. We want to find parcels that are accessible via a county road. In order to select all features within RuralU that overlap with the Roads_utm shapefile, you must use Select by Location:

17. Check the RuralU box within the Target Layer(s) and click on Roads_utm within the source layer drop-down menu. Leave all other options at default and click OK.

18. Right-click on the RuralU shapefile within the Table of Contents, Create Layer from Selected Features, and Export Data as a new shapefile and name it RuralURoads.shp.

Skill Drill 2: Select by Location

Our Final Parcel cannot intersect with any rivers or waterbodies, so the following steps will produce a selection of all RuralURoads that do not overlap with NHD_Proj.


19. Repeat these steps 15 to step 17, but with RuralURoads as the Target Layer(s) and NHD_Proj as the Source Layer.

1. Open the RuralURoads Attribute Table and click on the Switch Selection icon.

Switch Selection deselects all attributes currently selected and selects the remaining attributes that were not selected from the original query.

2. Create Layer from Selected Features and Export Data as a new shapefile named RuralURoadsNHD.shp. Add new shapefile to the Table Contents.

20. Since Wetlands_Proj extends beyond our area of interest, we will use the Clip tool to remove unnecessary data. Read the Help documentation to become more familiar with this tool.

21. From the Geoprocessing tab, click on Clip.


22. The Input Features will be the Wetlands_Proj shapefile and the Clip Features will be the CNTYOUTL_Proj shapefile. Output Feature Class is still the 02_Working Folder.

1. Name this shapefile Wetlands_C and click OK.23. From the Geoprocessing tab, click on Dissolve:


Dissolve allows the user to simplify shapefile data. Read the Help documentation to become more familiar with this tool.

24. Dissolve the Wetlands_C shapefile and leave all options except the Input Features and Output Feature Class as default.

We will utilize the Buffer tool to place our Music Festival 3200 meters (approximately 2 miles) from any wetlands within Humboldt County.

25. From the Geoprocessing tab, click on Buffer:


26. Leave all settings at default except Input Features (Wetlands_CD), Output Features Class (02_Working Folder), and the Linear unit (3200 meters):

You might notice that this is taking a horribly long time to process - this is because a buffer is being created around every single feature within the shapefile.

26. We want to remove all the parcels that have wetlands in them. Click on the Search button (or use the Ctrl+F trick) to open a search window:


27. Type in "erase" and hit [Enter], then click on the first option Erase (Analysis):

28. Input RuralURoadsNHD as the Input Features, and Wetland_Buff as the erase features and save your shapefile as "Erase.shp." This tool is fairly straight forward, in that it will erase all of the wetland from RuralURoadsNHD:


Adding XY Data

The Final Parcel must also be within cell phone tower range. Fortunately, we have access to a .csv file that has the latitude and longitude for each cell phone tower within Humboldt County. The next series of steps will instruct you on how to add this data and export it as a shapefile.


29. Download CellTowers_GCS.csv and save it to the 01_Originals folder. 30. Click on File within ArcMap, highlight Add Data, then click on "Add XY Data..." from the

drop-down menu:

31. Click on the folder icon and select CellTower_GCS.csv then choose LONG_DD as the "X Field" and LAT_DD as the "Y Field."

32. Click on "Edit..." and expand "Geographic Coordinate Systems," scroll down and expand "World," and select WGS 1984 and click OK:


33. Right-click on the CellTower_GCS.csv Events layer from within the Table of Contents and export it as a shapefile.

34. Project CellTower_GCS.shp into NAD_1983_UTM_Zone_10N and save as CellTower_UTM.shp. Add this shapefile as a layer to the Table of Contents.

Creating Buffers based on a Unique Field

For the next series of steps, we will be creating Buffers based on a unique field within the Attribute Table:

35. Right-click on CellTower_UTM within the Table of Contents and open the Attribute Table.

36. From the Table Options drop-down menu, click on Add Field:


37. Fill in the Name as Buffer, select Double from the drop-down menu and within Field Properties, input 10 for Precision and 5 for Scale:


38. From the Table Options drop-down menu, click on Select by Attributes...

We will be creating a unique buffer field based on four different values (3200, 4800, 6400, and 8000); the following steps will show you how to use Select by Attributes to select specific cell phone towers and assign a unique value to the newly created field.

Towers ("LOC_NO") Buffer

5, 10, 22, 25-27 3200

3-4, 7-9, 11-12, 15-21, 23-24 4800

1-2 6400

6, 13-14 8000

39. Double-click on "LOC_NO," the equal sign ("="), and then type in 6. Double click on "or," then "LOC_NO" and greater than or equal to (">=") 13 click on "And," then double click on "LOC_NO" and less than or equal to 14, then click on "Apply:"


40. Right-click on the Buffer Field, then select Field Calculator from the drop-down menu:


41. Enter 8000 and click on "OK"

42. Repeat for the other buffer distances.

Skill Drill 3: Select by Attributes - BOOLEAN Operators

42. Repeat these steps until the buffer values from the table above have all been applied to the CellTower_UTM Attribute Table.

43. From the Geoprocessing drop-down menu, click on Buffer and select CellTower_UTM as the Input Features, navigate to your 02_Working Folder to save your shapefile as CellTower_Buff.shp and click on the Field radio button. From the drop-down menu within Field, select Buffer. Read the Help documentation on selecting this field.

44. Leave all other options at default and click on OK:


44. From the Geoprocessing drop-down menu, select Intersect and intersect CellTower_Buff with Erase.shp and save the output as FinalParcel.shp.

45. Open the Attribute Table and clean up the dataset by right-clicking on columns empty of any data and select Delete Field:


46. Save your .mxd!

The Final Parcel (which should have two rows within the Attribute Table), will be utilized for Lab 7. The final selection should appear as follows:


In Lab Turn-In

Export and submit a TIFF of the Final Parcel at the end of lab.

Take Home Turn-In

A report that includes the parcel image and a description of the location as well as anything else outlined in Creating Reports in MS-Word.

Documents

· Web viewThis will create a new layer within the original name plus the word "selection": This new layer is a temporary selection layer that will vanish if you close your .mxd