Elemental Analysis of Astrosclereids in Needles of Old-growth Douglas fir Trees
EMSL Project ID
1990
Abstract
Objectives: Douglas fir is an ecologically and economically important tree in forests of the Pacific Northwest. Douglas fir needles contain large (150 5m) lignified cells known as astrosclereids, which are rarely found in needles from saplings but are almost always present in needles of old-growth trees when same-aged needles are compared. Tree age, and not needle age, appears to be an important determinant of their presence. Another factor which may influence the distribution of astrosclereids is soil chemistry. Astrosclereids were more abundant in needles from a site in the Oregon Cascades with lower soil nitrogen concentrations (4.3 megagrams/hectare) and slower mineralization rates (2.2 gNMin/m2/year) than at two other Cascade sites with higher nitrogen concentrations (5.4 gNMin/m2/year) and more rapid mineralization (10.1 megagrams/hectare). The objectives of this research are to explore the distribution of elements in needles with astrosclereids from old-growth trees. Knowledge of needle and astrosclereid composition will be useful in increasing our understanding of tree physiology and the interactions between soil chemistry and Douglas fir. Approach:Needles will be collected from the Wind River Canopy Crane site in Carson, Washington in June, 2000 by M. Apple and B. Bond. In June or July 2000, needles will be examined at EMSL by M. Apple and J. Young with SEM and EDS in order to determine their elemental compositions.Instrument performance needs:Scanning electron microscopeEnergy dispersive X-ray spectroscopy
Project Details
Project type
Exploratory Research
Start Date
2000-07-24
End Date
2000-12-31
Status
Closed
Released Data Link
Team
Principal Investigator
Related Publications
Perrine KA, BL Lamarche, DF Hopkins, SE Budge, LK Opresko, HS Wiley, and MB Sowa. 2007. "High Speed Method for In Situ Multispectral Image Registration." Microscopy Research and Technique 70(4):382-389.