Environmental impact of a hypothetical catastrophic leakage of CO_2 onto the ground surface

摘要

Environmental impact of CO_2 leakage from transport pipelines forms part of the overall EIA associated with development and progress of CCS and transport in the UK. Our work includes assessment of the effect on terrestrial flora from a hypothetical catastrophic leak of CO_2 into the environment.An experiment was designed utilising replicated enclosed cloches to elevate the CO_2 concentration of air above a grass sward. In an overnight gassing period (the most likely scenario for CO_2 pooling, prior to dispersion at dawn), CO_2 levels were raised to 42% (mean). Experiments were carried out in both October and June. The effects on selected plants were monitored, both in the short term (biochemistry of leaves) and long term (% change in species composition up to 12 weeks). Results indicated that an overnight 8hr exposure to high CO_2 concentration did not cause significant stress to plants and no significant change in species composition due to CO_2 was recorded.