Changes in Upland Wildlife Habitat on Farmland in Illinois 1920-1987

摘要

An index of upland wildlife habitat was devel- oped to investigate patterns and changes in habitat over time, using four years (1920, 1940, 1964, 1987) and the state of Illinois as an example. The index was composed of two subdivisions that described, at the county level, the quantity of wildlife habitat and a third subdivision that described farming disturbances that impacted he quality of the habi- tat. Data came from the US census of Agriculture.