A topographic map’s depiction of landscape is powerful and widely applicable.
Topographic maps, which show the contours of the landscape, are immensely powerful tools: They can help the outdoor adventurer find his or her way back home, identify areas prone to landslides to a development planner and reveal potential travel routes of hoofed mammals to a wildlife specialist. Not least, such maps can impart valuable lessons in geology and geomorphology to students, helping them appreciate the large-scale processes of landscape building occurring all around them.
Stream drainages are major features of topographic maps.
Considering the routes of drainages within a given watershed is one of the most straightforward and accessible topographic-map activities. Present the students with a map of the watershed encompassing your school or neighborhood. Show them the incisions that tributary streams can make on a landscape as they carve away through the cutting power of moving water, abrasive pebbles strung along in the current and gorge-wall erosion. Extend the thought exercise to the mother river of your drainage: in the United States, for example, you could tie many stream systems to the Mississippi, the Columbia or the Colorado. This would allow you to introduce the concept of a mature, meandering river and show its tight swings and broad floodplains on a topographic map.
Topographic maps of iconic landscapes can be good teaching aids.
Show a picture of a truly iconic landscape, such as the epic gorge of the Grand Canyon on the Colorado Plateau; the granite walls and verdant riparian flats of the Yosemite Valley in the Sierra Nevada; or the marl beds and isolated hammocks of the Everglades in southwestern Florida. Then associate this photographic or artistic evocation with a topographic map of the same area. This can be an effective tool to link the observed landscape — hill, valley, ridge, swamp or cliff — with the symbology of that topography in a set of contour lines.
Even the landscape of a suburb can be rendered in a topographic map.
Have the students create their own topographic map of their neighborhood or a favorite location. Alternatively, they can find a professionally rendered map through an online service or a print repository, such as the topographic maps of the U.S. Geological Survey (see Resources). Have them identify major physiographic landmarks: the high point of their watershed, depressions and stream channels, rugged places and relatively level ones.
Compare topographic maps with other depictions of the same landscape.
Show a topographic map of a given area alongside other cartographic representations of the same locale. This can demonstrate the power and complexity of maps. For example, a topographic map of the Willamette Valley in Oregon could show the cinder cones of the Boring Lava Field in the Portland area, as well as the converging floodplains of the Willamette and Columbia rivers and various isolated highlands such as the Eola and Coburg hills. A map covering the same area but depicting only vegetation types would align only partly with that geomorphic profile; so would a representation of population density in the valley.