GIS 4043 Lab 9: Vector Analysis 2

This week's lab continues the previous module's exploration of vector analysis.  This module introduced three tools that will undoubtedly be essential for future GIS work:  buffer, overlay and Python.  Buffer is a tool used to create zones of a defined distance around a feature.  Buffers become new layers which can be worked, combined and analyzed further.  In the above map I created for this lab, potential camping sites must be within 300 meters of a road as well as within 500 meters of a river or 150 meters of a lake.  Buffers for each of these can be created and added to the map.  To easily find areas that meet all the above criteria and create a new layer for them, an overlay tool can be used.  Using the overlay intersect tool, for example, would create a layer based upon the areas in which the input layers overlap (think of a Venn diagram).  There are six different overlay tools for different functions.  For example, another requirement for the camping area in the above map were that they not fall within conservation areas.  Using the erase overlay tool with the output of the intersection of the road and water buffers, we can create yet another layer that subtracts locations within conservation areas.

The third tool introduced was ArcPy and the use of Python in ArcMap.  This module included a fairly gentle introduction to using the program language, but it made clear how bulk processing is made easier with Python compared with going through the more user-friendly but more time-consuming ArcMap user interface.  I look forward to future courses diving further into using the Python programming language.