PARENT SESSION
Contributed Oral Session 164: Wetland Chemistry
Friday, August 12, 8:00 AM - 11:30 AM, Meeting Room 520 C, Level 5, Palais des congrès de Montréal
Impact of climate change on groundwater-fed wetlands in eastern England.
Herrera-Pantoja, Marina*,1, Hiscock, Kevin1, Boar, Ros1, 1 University of East Anglia, Norwich, NR4 7TJ, UK
ABSTRACT- Climate change is likely to have significant effects on wetland ecosystems and the considerable biodiversity that they support. Present-day and potential future climatic conditions over the next 90 years have been simulated for wetlands in eastern England using the Penman-Grindley soil water balance model and data from the UK Climate Impacts Programme (2002) at a resolution of 5 km2. Numerical groundwater models have simulated flow regimes and transient simulations have been run for the baseline period 1971-2000 and for the 2020s, 2050s, and 2080s with high climate impact scenarios. Finally, tolerances of wetland vegetation to dryness and wetness have been mapped using a GIS model. Results showed that for the study location, groundwater availability could decrease during the first part of this century, increase gradually for the subsequent 30 years, and rise by approximately 48% before the end of the 21st century. Significant stresses would occur in wetlands fed by semi-confined chalk aquifers since these proved the most sensitive to dry conditions. Several years of continued drought during the baseline years followed by a dry 2020s high impact scenario, dried out the modeled wetlands. Groundwater simulations also indicated that wetlands fed by semi-confined sandstone aquifers are very resilient to drought conditions. Nonetheless, after several years of drought and under the increased rates of evapotranspiration predicted for both the 2050s and 2080s scenarios, wetlands fed by semi-confined sandstone aquifers with low groundwater elevations might also be at risk of ecological disruption.
Key words: groundwater-fed wetlands, climate change, modelling