HR: 16:45h
AN: B12F-04 INVITED     [PDF]
TI: Dendrochemistry of base cations in red spruce: the fallacy of the passive recorder
AU: * Smith, K T
EM: ktsmith@fs.fed.us
AF: USDA Forest Service, Northeastern Research Station, P.O. Box 640, Durham, NH 03824 United States
AU: Shortle, W C
AF: USDA Forest Service, Northeastern Research Station, P.O. Box 640, Durham, NH 03824 United States
AB: Chemical analysis of red spruce (Picea rubens Sarg.) was conducted as part of a regional investigation on the response of forest trees and forest soils to acidic deposition. The goal of our dendrochemical research was to test the hypothesis that dendrochemistry provides a marker system for the occurrence and the timing of chemical changes in the tree rooting environment. Stringent comparisons of individual and aggregated radial trends of Ca, Mg, Mn, and K indicated that far from being a passive record of the external environment, dendrochemical patterns of these elements were based upon the factors of: 1) the active exclusion and preferential uptake and translocation of elements, 2) tree maturation from the formation of juvenile to mature wood, 3) wood maturation from sapwood to heartwood, 4) the interaction of tree wounding, infection, and tree response, and finally 5) changes in the external environment. Dendrochemical patterns need to be interpreted with consideration of these internal influences before attributing patterns to the external environment. Sample trends and qualitative models based on these factors will be presented. Preliminary analysis of Picea, Abies, Juniperus, Acer, Nothofagus, and Betula indicated that they may be even more rigorously limited in their utility as recorders of environmental factors that affect base cations.
DE: 0345 Pollution--urban and regional (0305)
DE: 0400 Biogeosciences
SC: Biogeosciences [B]
MN: 2003 Fall Meeting