Module 4: Vector Analysis

 

    In this module, we learned how to create buffers using a variety of overlay techniques. I created a fixed distance buffer by using the "buffer" tool and choosing the distance wanted; this was then applied to all features. To create buffers of varying distances, the "select by attribute" tool was used to apply a buffer of 150 to lakes and 500 for rivers, and then the "buffer" feature was used to apply the buffer. To create a multi-ring buffer, the "multi-ring buffer" tool was used, adding varying distances to create the rings. Then, I performed a union so that the roads buffer and water buffer would be displayed together. Another option would be to use the intersect feature- this gives the same results as the union feature. After adding the conservation_areas to the map, I used "erase" to exclude those areas from the buffer. 

    To display the various areas, I chose to use graduated colors instead of unique values since the areas are the same type, just different area sizes, and I used 3 classes to divide up the area size. The Field was set to area, as I wanted to map by area size. Method was set to equal interval to properly divide up the different sites by color. I chose yellow, orange, and red because they are easily displayed on the map, and the largest areas were displayed in red since the red stands out the most; the smallest areas were displayed in yellow since that color stands out the least on the map.