Land Use Planning and Urban Sprawl

Land conversion from one use to another is accelerating in the Mid-Atlantic region leading to increases in traffic congestion, land consumption, forest fragmentation, and impervious surfaces. These changes have important implications for hydrological dynamics, associated stream quality and, ultimately, the health of the Chesapeake Bay.

One of the goals of the Mid-Atlantic RESAC is to predict the future direction of urban growth and assist planners (e.g., MD Office Of Planning) to devise strategies to mitigate the undesirable consequences of unplanned growth. High resolution remote sensing is a promising technology for monitoring the growth of urban areas. For example, a decrease of the normalized difference vegetation index (NDVI) in Landsat satellite imagery provides an indicator of urban development with an overall accuracy of 85%, based on ground sampling. The Washington D.C. area has expanded at an average rate of ~22 km2/yr over the 26 yr. study period, with a period of extremely rapid growth occurring during the late 1980s. A simple calculation suggests that each additional person added to the metropolitan region accounts for ~600 m2 of additional landcover conversion. It appears that residential development favors the conversion of agricultural land, rather than forested land.

Ongoing research with Prof. Nancy Bockstael is making use of an economically-based land conversion model which has thus far been applied to 9 counties in the Chesapeake Bay watershed. The model is used in a predictive mode to develop land use scenarios in future periods which should significantly improve the current method based on extrapolations of demographic and land use trends. Policies that affect land use can be evaluated by comparing the model-predicted landscape configuration with and without the relevant policies. This type of land conversion modeling depends critically on current and historical (20 yr.), high-resolution land cover and land use data. We hope to generalize the analysis to determine whether high-resolution land use data collected at regular time intervals by satellites can be used to drive the model.

Conversion of farmland to residential, industrial and urban uses is also changing the character and economies of rural areas. Government agencies and conservation groups concerned with these issues are seeking better information on current land use trends. Population and agricultural census data and forest inventories provide some insight, but fall short in many respects. Land use/ cover data and change detection from remote sensing can provide much of the information needed. Mid-Atlantic RESAC partners (e.g., the Applied Spatial Research Center at JMU) articulates the needs of local and regional governments and help disseminate products to their constituents.

Landcover Mapping   Ecosystem Modeling   Land Manager Information System   Integrated Monitoring    Outreach