The seventh lab of Introduction to Geographic Information Systems forced us to find and organize our data layers with little supervision. Rather than being handed data, we were required to locate, download and organize data representing county boundaries, major roads, hydrography, cities, elevation, and public lands. We were also to choose one digital orthophoto quarter quad to incorporate into our layouts. Finally, we were to choose two of four environmental data layers to add into the mix. Since each of us were given a single county of Florida to focus on, most of the layers needed to be clipped to the extent of our respective counties. With the amount of data represented, we were forced to carefully organize our layouts so as not to overload the maps with too much information.
I did not run into any overly troublesome difficulties in finding and downloading the required data; I downloaded many more layers than I ended up using as I experimented with different data sources. Initially I planned on using a land cover layer as one of my optional environmental components. Unfortunately, the layer I found was so complex and information-rich that I did not want to tackle the task of wrangling it into a presentable form for this lab. Instead, I went with a shapefile of invasive plant species available from the Florida Natural Areas Inventory website.
After all my layers were downloaded, I tossed several crude maps together with different combinations of layers to see what would work best. The division that seemed most natural grouped the "human" data (cities, roads, public lands) in one map and the environmental data (invasive species and wetlands as well as elevation) into another. I could have plausibly included surface water in both maps, but I thought including it in the environmental map would have been unnecessary given the presence of the wetlands data. I was worried about shoehorning the DOQQ into one of the maps, but using it to expand an especially concentrated section of invasive plants seemed to work well. The only problem was that, when using the 'clip to shape' option of the data frame properties to clip my DEM raster to the Gadsden County outline, the extent indicators for my orthophoto were also clipped. After some searching amongst ArcMap's help files and more experimentation, I found the 'Mask (Environment setting)' tool functioned just as well for my purposes without clipping the extent indicators.
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