LAND-USE CHANGES IN EAST TENNESSEE AND A SIMULATION MODEL WHICH DESCRIBES THESE CHANGES FOR THREE COUNTIES

摘要

The rates of change and amounts of nine land-use categories were determined for five counties in East Tennessee (Rhea, Meigs, Roane, Loudon and Knox). Data were collected from a 1939 TVA field map and aerial photographs from 1953 and mid-1960. Within each square kilometer cell, the fraction of land occupied by each land-use was determined. These land-use types include: open (primarily agriculture), old field (non-forest including power line cuts), pine forests or plantations, cedar-hardwood, mixed and hardwood forests, water, urban and special (a "catch-all" including steam plants, quarries, etc.). All five counties are shifting from open land to forest, water, urban and special land-uses with an average yearly decrease in non-forested land of 5.28 km2 year-1, of which 2.39 km2. year-1 represents an increase in forested land and 2.85 krn2 year-1 is irreversibly lost to water, urban and special uses. Approximately 160 km of land was lost to water in Meigs, Rhea and Roane counties -- the largest change in any land-use category other than open land.nUsing the data averaged for Meigs, Rhea and Roane counties, a simulation model was developed to investigate both land-use changes and how man influences rates of change. The 1939 data were used as initial conditions for the constant coefficient model which predicted the amount of land in each usage for the next two time periods. Time varying coefficients were used to account for effects of dams on the Tennessee River and influence of Bowaters pine pulp and paper mill on the rate of establishment of pine plantations. The simulation indicates that man's influence on the landscape necessitates a more complex model;for example, pine and water were not even closely approximated in 1964 if time varying coefficients were not included.