Floristics of the Abrams Creek Wetlands, a Calcareous Fen Complex in Winchester City and Frederick County, Virginia

摘要

The 24-ha Abrams Creek Wetlands (Winchester City and Frederick County, Virginia) is an array of fen, swamp, and disturbed transitional ecosystems underlain by limestone and dolostone bedrock. Soils of the area are generally characterized by exceptionally high levels of calcium (&10,000 ppm). Floristic data were collected through monthly surveys during the 2012-14 growing seasons and plot sampling in representative locations. We documented 296 vascular plant species during the inventory period; eight species found previously were not relocated. The 304 total species comprised 206 genera in 78 families. Of these, 55 species were graminoids (27 grasses, 21 sedges, 7 rushes). Obligate or facultative wetland species comprised 43% of the list. The 216 native species represented 71% of the total and included 20 listed as rare in Virginia. Plot data revealed that native species represented 72-99% of the total vegetative cover in the communities sampled. Floristic quality of the 12 constituent sites was consistently high, with Floristic Quality Assessment Index (FQAI) scores between 30 and 44; the property as a whole scored an exceptional FQAI of 67. Constricted and fragmented by suburban and rural development, the Abrams Creek Wetlands nonetheless supports distinctive ecological assemblages that are characterized by native wetland calciphiles, many of which are rare statewide.