1. Site Selection Making Spatial Decisions Using GIS January 26, 2011Site Selection - IAP 2011

2. Why would I use Site Selection Tools? January 26, 2011Site Selection - IAP 2011  Decide on an appropriate location for a new building  Uncover areas of risk for geologic hazards  Pinpoint areas for development  Establish safe zones for habitation

3. Add Layers of Data to GIS January 26, 2011Site Selection - IAP 2011  Census  Infrastructure  Environmental Analyze Layers Together

4. Keep in mind… January 26, 2011Site Selection - IAP 2011 Data issues in vector processing  Complex world, simplified data  Real world becomes vector data (as points, lines and polygons)  You choose which data to use, and how to represent it.

5. Selection of features for use in a GIS January 26, 2011Site Selection - IAP 2011  Only details of interest to the creator are stored in the data.  Metadata: who made the data and why you should use it, or not!

6. Representation of data January 26, 2011Site Selection - IAP 2011  Tied to scale and data type  City as point or polygon?  Vector objects in a GIS have defined boundaries, unlike nature (transition in forests)

7. Overlay operations in a GIS January 26, 2011Site Selection - IAP 2011  Origins in Landscape Planning  Set theory – polygons represent sets, overlay represents intersects, unions and symmetrical difference

8. Some Analysis Tools: January 26, 2011Site Selection - IAP 2011  Clip  Buffer  Union  Symmetrical Difference  Spatial Join  Add XY Data

9. Clip January 26, 2011Site Selection - IAP 2011

10. Buffer January 26, 2011Site Selection - IAP 2011

11. Union January 26, 2011Site Selection - IAP 2011

12. Intersect January 26, 2011Site Selection - IAP 2011

13. January 26, 2011Site Selection - IAP 2011 Symmetrical Difference

14. Spatial Join January 26, 2011Site Selection - IAP 2011 Point in polygon operation – which points are in the Polygon? Polygon ID (id_1) is added to the point layer’s attribute table.

15. Add XY Data January 26, 2011Site Selection - IAP 2011

16. Things to consider: January 26, 2011Site Selection - IAP 2011  Vector data processing is CPU intensive.  Inaccurate data in inaccurate data out

17. Our project: January 26, 2011Site Selection - IAP 2011 Find a building location for a visitor’s center at Great Meadows Wildlife Refuge in Bedford, Carlisle and Concord, MA

18. January 26, 2011Site Selection - IAP 2011

19. January 26, 2011Site Selection - IAP 2011