Ground-Dwelling Macroinvertebrate Biodiversity as a Determinant of Forest Health in Morris Woods
Bryn Mawr College. Department of Biology
Place of Publication
Table of Contents
The edge effect is a phenomenon that occurs when two or more ecosystems overlap to form a ‘border’ environment that is ecologically different from the surrounding biome. The nature and magnitude of the edge effect can be elucidated through direct examination of a myriad of environmental and biotic factors, including macroinvertebrate diversity, soil temperature, and canopy coverage. Extensive pitfall trapping, canopy coverage assays, and soil temperature probing were conducted in interior and edge plots in Morris Woods, a relatively small temperate forest in suburban SE Pennsylvania. No significant differences appeared to manifest within measurements of soil temperature (Tinterior = 15.63 oC; Tedge = 16.23 oC; 2-‐tailed SEM1, p > 0.05) and canopy coverage (Cinterior = 91.64%; Cedge = 88.31%; 2-‐tailed SEM, p > 0.05) between the edge and interior plots, though observable differences in macroinvertebrate abundance (Ninterior = 179; Nedge = 262), species richness (Rinterior = 2.127; Redge = 1.259), and species diversity (Dinterior = 0.5864 ; Dedge = 0.4151) were evident. Results also indicated that the interior plot supports more macroinvertebrate taxa and more environmentally sensitive taxa than the edge plot, indicating that that the interior plot likely exhibits higher niche richness, though the factors of soil temperature and canopy coverage did not appear to account for these differences.