Dry deposition of 214Pb to conifers

The dry deposition of 214Pb was investigated by measuring airborne activity and activity accumulated on Douglas fir branches. This radioisotope is a natural tracer for submicron aerosol. The correlation of the deposition velocity with turbulence intensity is poor. The best estimate of the average deposition velocity for 214Pb is 0.0073 ± 0.0010 m s−1 This value is somewhat lower than the average deposition velocity for sulphate aerosol of 0.011 ms−1 at this site, determined in a concurrent study.