Tracking farmland conversion and fragmentation using tax parcel data

ABSTRACT:

Analyses of farmland conversion typically rely on data that has been aggregated to a county level. However, the pattern of farmland conversion at the individual parcel level could have important implications for the sustainability of agricultural operations within a limited geographic area. This paper uses data on farm parcels that have withdrawn from Tennessee's differential assessment program to track farmland conversion at the individual tax parcel level for a single east Tennessee county. The pattern and pace of farmland conversion is described over an 18-year period and a metric from the habitat fragmentation literature—edge density—is used to quantify the extent to which this conversion has increased the fragmentation of the county's remaining agricultural lands. Edge density, as used in this paper, provides a relative measure of the extent of the interface between agriculture and other land uses. The results suggest that agricultural lands became more fragmented every year for which data was available, although the extent of this increase varied substantially from one year to the next. More specifically, while conversion to residential use increased fragmentation, conversion to both commercial and industrial uses tended to decrease fragmentation. The data and methodologies employed in this paper, although relatively new to the farmland conversion literature, could prove to be valuable tools in analyzing the conversion of agricultural lands and in designing policies to ameliorate the adverse effects of such conversion.