10.2190/3A9U-2H0C-4L37-8TBL 3A9U2H0C4L378TBL 6 Speed-Dependent Modeling of Ecosystem Exposures from Vehicles in the Near-Road Environment 185 192 20020509 20020509 20020509 20020509 3A9U2H0C4L378TBL.pdf http://baywood.metapress.com/link.asp?target=contribution&id=3A9U2H0C4L378TBL 2 J. S. Pandey P. Khanna National Environmental Engineering Research Institute, Nagpur, India The article presents a model of automobile exhaust emissions in terms of vehicle speed and plant stomatal resistance. The software, which offers several advantages in environmental decision making, has been developed for computing gas—specific flux contributions and total daily ecosystems—health exposure—risk for a near road environment under strong wind conditions. Concentration differential has been taken as proportional to the emission values from vehicles at different speeds. Flux contributions from different gaseous pollutants, and total daily exposure-risks have been computed as a function of vehicular speed and PAR-dependent curvature-coefficient. The calibration and validation of the model will be cost effective, as the number of parameters included in the model is significantly lower than the number required in the conventional models. E. A. Wright, P. W. Lucas, D. A. Cotton, and T. A. Mansfield, Physiological Responses of Plants to SO₂, NO₂, and O₃: Implications of Drought Resistance, in <i>Direct Effects of Wet and Dry Deposition on Forest Ecosystems</i>, CEC COST 612 Workshop, Loekberg, Sweden, pp. 187-200, October 1986. A. S. Thorn, J. B. Stewart, H. R. Oliver, and J. H. Gash, Comparison of Aerodynamic and Energy Budget Estimates of Fluxes over a Pine Forest, <i>Quarterly Journal of the Meteorological Society 101</i>, pp. 93-105, 1975. N. C. Turner and J. E. Begg, Stomatal Behaviour and Water Status of Maize, Sorghum and Tobacco under Field Conditions. I: At High Soil Water Potential, <i>Plant Physiology, 51</i>, pp. 31-36, 1973. D. J. Schaeffer, E. E. Herricks, and H. W. Kerster, Ecosystem Health: I. Measuring Ecosystem Health, <i>Environmental Management, 12</i>:4, pp. 445-455, 1988. C. Williams and M. Southhall, <i>Inservice Emissions of Cars Manufactured to Meet ECE Regulations, 15.</i> MIRA Report K 3404, Motor Industries Research Association, Nuneaton, United Kingdom, 1976. C. Williams and M. J. Everett, <i>Inservice Emissions of 204 Vehicles Manufactured between 1971-1982</i>, MIRA Report K 32126, Motor Industries Research Association, Nuneaton, United Kingdom, 1983. Watt Committee, <i>Report no. 14—Acid Rain</i>, The Watt Committee on Energy, London, 1984. T. M. Hinckley, R. G. Aslin, R. R. Aubuchen, C. L. Metcalf, and J. E. Roberts, Leaf Conductance and Photosynthesis in Four Species of the Oak—Hickory Forest Type, <i>Forest Science, 24</i>, pp. 73-84, 1978. D. D. Baldocchi and B. A. Hutcinson, On Estimating Canopy Photosynthesis and Stomatal Conductance in a Deciduous Forest with Clumped Foliage, <i>Tree Physiology, 2</i>, pp. 155-168, 1986. P. Elias, Leaf Diffusion Resistance Pattern in an Oak—Hornbeam Forest, <i>Biologia Plantarum, 21</i>, pp. 1-8, 1979. J. S. Pandey, A. Shankar, and P. Khanna, Investigations into Behavioural Modes of a Forest Growth Model, <i>J. Environmental Systems, 19</i>:4, pp. 349-354, 1990. B. M. A. Kroon, H. A. M. Ketelaars, H. J. Fallowfield, and L. R. Mur, Modelling Microalgal Productivity in a High Rate Algal Pond Based on Wavelength Dependent Optical Properties, <i>Journal of Applied Phycology, 1</i>, pp. 247-256, 1989. J. J. Finninan and M. R. Ranpach, Modern Theory of Transfer in Plant Canopies in Relation to Stomatal Characteristics, in <i>Stomatal Function</i>, G. Farquhar and I. Cowan (eds.), Stanford University Press, Stanford, California, 1987.