Dissolved organic nitrogen in precipitation: Collection, analysis and atmospheric flux

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:462563

Scudlark, J R; Church, T M ^[1]; Russell, K M ^[2]; Montag, J A; Maben, J R; Keene, W C; Galloway, J N ^[2]

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1. Univ. of Delaware, Lewes, DE (United States). Graduate Coll. of Marine Studies
2. Univ. of Virginia, Charlottesville, VA (United States). Dept. of Environmental Sciences

Recent studies have documented the importance of atmosphere inorganic nitrogen deposition to coastal waters. However, due to the limited number of field measurements and concerns about the reliability of measurement techniques, the aeolian flux of organic N is very uncertain. Coordinated studies have been initiated at Lewes, DE and Charlottesville, VA to evaluate collection and analysis techniques for dissolved organic nitrogen (DON) in precipitation and to provide preliminary estimate of DON wet fluxes. Sampling was conducted both manually and employing an automated wet-only collector (ACM) on a daily basis. A total of 37 events were analyzed from October 1993 through December 1994. Side-by-side comparisons of standard white HDPE buckets and stainless steel and glass collection vessels indicate sampling artifacts associate with plastic buckets. DON in precipitation appears to be highly labile, with significant losses observed in some samples within 12 hours. Analytical methods evaluated include persulfate wet chemical oxidation, UV photo-oxidation and a modified high temperature instrumental (ANTEK 7000) technique. Based on preliminary results, the volume-weighted average concentration of DON in precipitation at the mid-Atlantic coast is 9.1 {micro}moles/1. On an annual basis, DON compromises 23% of the total dissolved nitrogen in precipitation, varying from 0--64% on an event basis. From an ecological perspective, DON wet flux represents a quantitatively important exogenous source of N to coastal waters such as Chesapeake Bay.

• OSTI ID: 462563
• Report Number(s): CONF-961149--
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AIR POLLUTION
AIR POLLUTION MONITORING
CHEMICAL ANALYSIS
ECOLOGICAL CONCENTRATION
ORGANIC NITROGEN COMPOUNDS
PRECIPITATION SCAVENGING