Evaluation of the uncertainty in the ozone flux effect modelling: from the experiments to the dose-response relationships

The paper is anattempt to assess theuncertainty involved in themodellingprocess ofderiving thefluxeeffects\r\nrelationships from the experimental evidences of a network of coordinated experiments on ozone and\r\nvegetation (the LRTAP Convention’s ICP Vegetation).\r\nTen modelling steps have been described and analysed. Even if some steps were more critical than\r\nothers in introducing uncertainty, the whole modelling process seems to be quite robust.\r\nThe stomatal dose calculation is precise enough when performed on long time periods (e.g. growing\r\nseason). The main sources of inaccuracy for the stomatal dose calculation can be ascribed to the adoption\r\nof different schemes for the calculation of ozone concentration at leaf level (7e10%). The estimation of\r\nthe ozone effects on vegetation, and particularly the derivation of the plant’s response at the theoretical\r\nzero-ozone dose, proves to be the main source of uncertainty of the whole process (up to 17%). In order to\r\nimprove the precision of this step an increased number of ozone treatments and replicates in the\r\nexperiments is recommended, while a harmonization/standardization of the calculation algorithm is\r\nrequired to improve the accuracy of the dose calculation.