CHARACTERIZATION OF POLLEN DEPOSITION IN A FOREST ENVIRONMENT

Measurements of the dry deposition of pollen were made during the months of May and June 1987 in northern Wisconsin, using a smooth surrogate surface. Samples were taken on a raft located on Little Rock Lake and at a nearby field monitoring station. Rain samples were also collected at the field station. The wet SO42- flux was 102.7 mg m-2, compared with a dry SO42- flux of 118 mg m-2 at the field monitoring site and 45 mg m-2 at the lake site. The SO42- content of pollen ranged from 0.2 to 0.8% of the weight of the pollen, and NO3- concentrations were an order of magnitude lower. Between 9 and 22% of the pollen weight was available as total organic carbon (TOC) upon addition to water. The addition of pollen to distilled water produced an acid reaction, due to organic acids and not inorganic acidity. © 1990.