Preprints of Extended Abstracts Vol. 41 No. 1 ENVIRONMENTAL TRENDS (Cosponsored with ACS Committee on Environmental Improvement Organized by T.L. Wade Symposia Papers Presented Before the Division of Environmental Chemistry American Chemical Society San Diego, CA April 1-5, 2001 TRACE ELEMENTS IN THE AQUATIC ENVIRONMENT OF HAWAII: EFFECTS OF URBANIZATION Eric Heinen De Carlo1, Vincent L. Beltran1, Michael S. Tomlinson1, Khalil J. Spencer2 and Julia E. Hubert1 1Department of Oceanography, SOEST, University of Hawaii, 1000 Pope Road, Honolulu, HI 96822 Fax: 808-956-7112,
[email protected] 2Department of Geology and Geophysics, SOEST, University of Hawaii In small subtropical island watersheds, material inputs to the ocean are dominated by freshwater pulses associated with intense but often abrupt orographic rainstorms. The rugged topography and high rainfall intensity typical of the main Hawaiian Islands results in rapidly changing hydrographic conditions that present an opportunity to study the spatial and temporal evolution of material as it travels through the watershed to the ocean. Because the island of Oahu, and Honolulu in particular, have been extensively urbanized during the second half of the 20th century, transport of suspended particulate matter (SPM) during storms represents an important vehicle for the mobilization of anthropogenic material deposited throughout the watersheds during the past half century. Rainstorms generated by orographic uplift of warm and moist tradewinds often occur at night, when a rapid response and deployment of manual sampling equipment is difficult at best. Additionally, because the response of streams to storms in Oahu watersheds is rapid (e.g., Fig 2), automated sampling is imperative to capture samples from the representative limbs of rapidly changing hydrographs.