You are here:
A COMPARISON OF ANALYSIS UNITS FOR ASSOCIATING LYME DISEASE WITH FOREST-EDGE HABITAT
JACKSON, L., J. F. LEVINE, AND E. D. HILBORN. A COMPARISON OF ANALYSIS UNITS FOR ASSOCIATING LYME DISEASE WITH FOREST-EDGE HABITAT. Community Ecology. Hungarian (Magyar) Ecological Society, Budapest, Hungary, 7(2):189-197, (2006).
To assess the relationship between land-cover pattern and Lyme disease incidence rate
This study assessed the relationship between land-cover pattern and Lyme disease incidence rate when modeled under three designs for data aggregation. Incidence rates were calculated from passive surveillance data reported in 12 Maryland counties during 1996 2000. A design using road-bounded analysis units that varied in size from 0.002 km2 to 368 km2 (n = 415) was compared with designs that used grid cells of 10 km2 (n = 823) and 36 km2 (n = 230). Major roads were chosen to approximate bounded populations of deer and humans engaged in outdoor activity around the home. While cell boundaries were arbitrary, cell size was driven by attempts to minimize large under-estimations observed in a previous model, and to standardize the presumed zone of exposure. The parameter that explained the most variation in incidence rate across all study designs was percent of herbaceous edge adjacent to forest. Also significant under each design was percent of herbaceous cover. This relationship was quadratic, with incidence rate peaking at 44 to 58 percent of this cover type. Herbaceous cover refers to pasture, row crops, and grass. The strongest model (R2 = 0.87) resulted from the road-bounded design. However, the high explanatory power of forest-herbaceous edge across all methods of data aggregation highlights the importance of this landscape feature to Lyme disease rates. Design strategies may help to minimize Lyme disease in variously-defined landscapes by reducing forest-herbaceous edge while meeting other land-use needs.