HR: 1340h
AN: B33B-1030    [Abstracts]
TI: Fog and Phosphorous:Mist Connections?
AU: * Weathers, K C
EM: weathers@ecostudies.org
AF: Institute of Ecosystem Studies, Box AB, Millbrook, NY 12545 United States
AU: Caraco, N F
EM: caracon@ecostudies.org
AF: Institute of Ecosystem Studies, Box AB, Millbrook, NY 12545 United States
AU: Ewing, H A
EM: hewing@bates.edu
AF: Bates College, 111 Bardwell St. Environmental Studies Program, Lewiston, ME 04240 United States
AB: Fog (or cloud) is an important vector for delivering water, nutrients and pollutants to many coastal and montane ecosystems worldwide. Previous research has demonstrated that elements and ions whose sources are thought to be atmospheric, such as nitrogen and sulfur, can be deposited in substantial quantities via fog water deposition. However, the ecologically-important nutrient, phosphorous (P), is thought to derive primarily from guano or terrestrial sources; it has not been demonstrated to be deposited in significant quantities via rain water, for example. Here we suggest that phosphorous may be quite prevalent in fog water and that the atmospheric deposition of phosphorous to the forest floor is significant. Phosphate appears to be either immobilized or utilized in the forest floor. We examine the concentrations of phosphorous in fog water from several ecosystems in the Americas and the spatial patterns of P movement in a fog-dominated, redwood forest in Sonoma County, CA. Phosphate concentrations were surprisingly high, ranging from 0.002 to 2.9 mg/L, in fog samples from near-coast and montane ecosystems. Phosphate in fog water appears to be derived from a crustal source as demonstrated by the strong relationship between phosphorous concentrations in fog and K:Na ratios. Fog water phosphorous inputs to the forest floor were observed to decline exponentially and vary significantly from edge to interior in a redwood forest. Phosphate via fog deposition can be detected in shallow soil zones but not at greater depths, and only at the forest edge, during the summer fog season.
DE: 0414 Biogeochemical cycles, processes, and modeling (0412, 0793, 1615, 4805, 4912)
DE: 0439 Ecosystems, structure and dynamics (4815)
DE: 0470 Nutrients and nutrient cycling (4845, 4850)
DE: 0499 New fields (not classifiable under other headings)
SC: Biogeosciences [B]
MN: Fall Meeting 2005