Sampling ozone exposure of Canadian forests at different scales: some case studies.

摘要: The use of passive samplers in extensive monitoring, such as that used national forest health monitoring plots, indicates these devices are able to determine both spatial and temporal differences ozone exposure the plots. This allows for categorisation plots potential cause-effect analysis certain responses. Forest along a gradient air pollution deposition demonstrates large variation accumulated exposures. efficacy using situ canopy was also demonstrated. sampler data produced weak relationships with values from nearest �continuous� monitor, even though colocated showed strong relationships. apparent effect elevation on demonstrate importance topography tree characteristics plant regional scale. In addition, sampling may identify effects local pollutant gases, NO, which scavenge locally only increase production this secondary downwind, atmospheric reactions redress equilibrium between concentrations precursor those generated ozone. at stand level is resolve vertical profiles within edge important understorey ground flora. Recent case studies indicate great development models regional, landscape,