Landcover Maps
Landcover maps can be used to assess and analyze land use change and forest fragmentation in the United States.
What is Forest Fragmentation?
The 2002 Southern Forest Resource Assessment defined forest fragmentation as the breaking up of large, contiguous forested tracts into smaller or less contiguous tracts. This means that forests become islands and peninsulas—patches of woods disconnected from one another by roads, farms, suburbs, cities, and other human activities.
Forest fragmentation has a wide range of effects on ecosystem services, defined simply as the benefits that forests provide to us. In addition to providing wood products, fuel, medicine, and recreation, forests also:
- Clean our water and air
- Provide habitat to a huge diversity of life forms
- Take up carbon dioxide and produce oxygen
- Regulate climate by sequestering carbon
- Maintain the health of soil
- Absorb and detoxify pollutants
- Provide the setting for a wide range of recreational activities
When forests are divided into smaller and smaller parcels, the biological diversity of native animals and plants is diminished, water cycles are altered, nonnative invasive plants and animals are introduced, and air and water quality are affected. Forests weakened by fragmentation become more susceptible to damage from insects and diseases, and coming under stress, often degenerate into a condition of chronic ill health.
(Adapted from the Southern Research Station general technical reports: Human Influences on Forest Ecosystems and the Southern Forest Resource Assessment.)
Sometimes a Great Notion: Visualizing Forest Fragmentation
It may seem pretty obvious that American forests are being split apart by roads, houses, and strip malls, but, until recently, it was difficult to visualize the extent and magnitude of forest fragmentation in the United States. Until, that is, Southern Research Station (SRS) researcher Kurt Riitters and his collaborators started applying a method called “moving windows” to landscape analysis….
(From Forests Under Siege: Fragmentation accelerates in the South, Compass, Fall 2005.)
The following Google Earth maps represent research that Riitters and his partners have focused on forest fragmentation and related wildlife corridors. The landcover maps provide a deeper, visual experience for those interested in how fragmentation is affecting urban and rural areas of the U.S., and perhaps activities in a city or town near you.
Select a topic:
Forest Area Density
Find more information about land use change and forest fragmentation here.
Photos (top to bottom): Derek Jensen, www.wikimedia.org; Rod Kindlund, USDA Forest Service Southern Research Station; Larry Korhnak, www.interfacesouth.org