HR: 0800h
AN: H31F-0730    [Abstracts]
TI: Rehabilitation of Abandoned Quarries to Calcareous Fens: Ecohydrological Insights from Natural Systems
AU: * Duval, T P
EM: duvaltp@mcmaster.ca
AF: School of Geography and Earth Sciences, McMaster University, 1280 Main St W, Hamilton, ON L8S4K1, Canada
AU: Waddington, J M
EM: wadding@mcmaster.ca
AF: School of Geography and Earth Sciences, McMaster University, 1280 Main St W, Hamilton, ON L8S4K1, Canada
AU: Branfireun, B A
EM: brian.branfireun@utoronto.ca
AF: Department of Geography, University of Toronto at Mississauga, 3359 Mississauga Rd N, Mississauga, ON L5L1C6, Canada
AB: Calcareous fens are some of the most species diverse ecosystems in temperate North America and often occur in watersheds where groundwater flows through easily weathered limestone or dolostone bedrock. Many limestone aggregate quarries are abandoned when it is no longer cost-effective to mine below the water table. The remaining disturbed site then represents a possible habitat for the many calciphilic species that comprise a calcareous fen. Thus, there exists an opportunity for industry to implement sound ecohydrological management protocols to provide an overall biodiversity increase at extraction sites. This study explores the ecohydrological controls on calcareous fen species distribution at three natural sites in the headwaters of a southern Ontario watershed. We also present initial work on the feasibility of rehabilitating an adjacent abandoned aggregate quarry to a calcareous fen through transplant experiments. Vegetation communities between the natural sites were significantly different in almost all cases, with individual species responding differently to hydroperiod. These community differences were related to the hydrogeomorphic setting of the natural sites, which controlled the amount and source area of water to the wegetation. At the plot-scale, species richness was negatively correlated with mean water table depth and peat carbonate content, and positively correlated to peat organic matter content. In the quarry transplant experiments, total number of stems and aboveground biomass were significantly greater in a treatment amended with topsoil, and regardless of soil treatment, biomass in plots placed in shallow water (15 cm below ground) was significantly less than plots in deeper water. These results demonstrate the range of hydrological conditions influencing the ecology of calcareous fens, in addition to shedding light on some key constraints on rehabilitation efforts.
DE: 1803 Anthropogenic effects (4802, 4902)
DE: 1813 Eco-hydrology
DE: 1847 Modeling
DE: 1874 Ungaged basins
DE: 1879 Watershed
SC: Hydrology [H]
MN: 2007 Fall Meeting