Measuring Land Preservation Success: Applying Fragstats to Preserved Farmland in Lancaster County, Pennsylvania

Abstract

Edge effects are traditionally discussed in biogeography and ecosystem protection. Yet preserved farmland can also experience challenging pressures at its perimeter, such as increased development pressure and conflicts between farms and nonfarm neighbors. Academic assessments of the most common farmland preservation goal—large, contiguous blocks—have focused on the area and connectivity of preserved parcels and largely overlooked the block or shape component, which relates most strongly to these types of pressures. This study fills that gap, applying the edge-effects concept to preserved farmland for the first time and tracking the shape of preserved farmland patches in Lancaster County, Pennsylvania, a leading agricultural county in the United States. The study uses the spatial pattern analysis program Fragstats to examine preserved farmland patch size, shape, and area in Lancaster County between 2000 and 2023. Results show that although land preservation organizations in Lancaster County had success at increasing the area and contiguity of preserved land, the perimeter of farmland patches increased even more significantly, even when accounting for differences in area. Farmland patches became increasingly irregular over the study period, with meandering shapes that maximize edge. The outcome suggests that tracking edge separately from area and contiguity is important because success in one does not mean success in the others. Information on edge and shape can help land preservation organizations prioritize parcels that reduce the edge effects that make it more expensive to purchase easements and more challenging for farmers to keep farming.