Past Research 1996-2002

P-IB. Human-caused land cover change during the last half-century
Summary: 
Humans have become the single largest disturbance factor in most landscapes, altering more vegetation and moving more soil than natural biotic and physical processes combined.

The primary human disturbances in the southern Appalachians are forest harvesting for wood products and land conversion to agricultural or urban/suburban land uses. We hypothesize that the frequency, intensity, and extent of these two types of disturbance have changed over the last 50 years, due to both physical/biotic conditions and to policies, politics, and laws established during this time period. Furthermore, impacts of these changes in land-use cascade through both terrestrial and aquatic ecosystems in the southern Appalachians. Land-use change data are crucial for developing and validating socio-economic models of factors causing land-use change, but also provide key sampling frames and data for other projects, including research on carbon, nutrient, and water cycles, terrestrial ecosystem fragmentation and biotic diversity, and aquatic ecosystem response to disturbance.

We have three objectives:
(1) Obtain decadal time series of detailed land-use/land cover data from the 1940s until present, which include classes for forest (young and old), agriculture, old fields, and urban/suburban areas.
(2) Digitize time series and overlay to identify the range of land conversion/land-use characteristic size, location, and configuration, and to estimate conversion frequencies.
(3) Identify land-use trajectories and identify key sampling frames for related studies.

Recent land-use changes were studied in four representative areas and the changes in land-use/land cover (LULC) mapped for 1950, 1970 and 1990 using aerial photos and satellite imagery to create a common data set. A spatially explicit model of land-use change over the 40-year period identified physical and human factors determining land-use patterns, e.g., topography and the primary road network strongly influenced building density and land-cover change. Land-cover changes are more frequent at lower elevations and near roads suggesting that development concentrates in sensitive riparian areas.

Previous Research on Topic (Literature Search)

Metadata:
Regionalization Projects Metadata

GIS Metadata

Data:
GIS Data

Investigators and Collaborators:
Paul Bolstad

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