2005 BES Annual Meeting Presentation and Poster Abstracts
Variations in Calcium and Arthropod Abundance in Residential Yards along an Urban to Rural Gradient
Murawski, L., C. Wong, K. Szlavecz, R.V. Pouyat, P. Marra, S. Lev, and C. Ryan
Abstract: Rapid urbanization at regional and global scales necessitates an understanding of these newly formed urban habitats. Previous studies indicate that regional and local scale deposition contributes a significant amount of calcium to soils in urban areas. Calcium is known to limit the growth of soil isopods and studies have shown that soil isopod abundances are higher in urban than in rural forest patches. While these studies have focused on forested areas along an urban to rural gradient, residential areas have not been investigated though they are the dominant land use in urban areas. This study addresses the following questions: Does calcium vary in residential soils i) regionally across an urban to rural land use gradient and ii) locally within yard patches (front yard, backyard, proximity to road, and home) and iii) do isopod abundances correspond with soil Ca concentrations? The sites used in this study correspond with the Neighborhood Nestwatch network in the Washington D.C and Baltimore Metropolitan areas. Calcium levels were more than two-fold greater in suburban sites than the other land use types. Isopod abundance in urban areas was highest, and pH significantly correlated with calcium levels in the soil. The results suggest that calcium levels and arthropod abundance are being affected by more than local and regional deposition.