Allen Craig, Midcontinent Ecological Science Center, USGS
This report discusses land use and landscape changes in the southwestern United States. Themes that are explored are the importance of climatic variability in driving ecological processes and modulating human land uses, and the use of historical and paleoecological data to detect and explain trends in ecological patterns and processes across southwestern landscapes. Also discussed are the effectiveness of regional network approaches in the development of historical data sets, the use of historical data to discriminate between natural and cultural causes of environmental change, and the use of historical data to define and constrain natural ranges of variability and, in some cases, to set targets or determine templates for restoration and sustainable use of ecosystems. Topics include the paleobotanical record, ground-based and aerial photography, and fire-scar histories. Text is accompanied by maps, graphed data sets, and a list of additional references.