Record Display for the EPA National Library Catalog


Main Title Use of quality control procedures to assess errors in measuring forest canopy condition /
Author Cline, Steven P. ; Burkman, W. G. ; Geron, C. D.
Other Authors
Author Title of a Work
Burkman, William G.
Geron, Chris D.
CORP Author Corvallis Environmental Research Lab., OR. ;NSI Technology Services Corp., Corvallis, OR.
Publisher U.S. Environmental Protection Agency, Environmental Research Laboratory,
Year Published 1989
Report Number EPA/600/D-89/105; ERL-COR-1050D
Stock Number PB90-113770
Additional Subjects Damage assessment ; Pine trees ; Forest trees ; Air pollution ; Maple trees ; Measurement ; Quality control ; Field tests ; Laboratories ; Errors ; Ratings ; Acidification ; Photographs ; Mortality ; Transparence ; Acid precipitation ; Forest Response Program ; Tree canopy
Library Call Number Additional Info Location Last
NTIS  PB90-113770 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 19 pages ; 28 cm
Quality control data collected during the measurement of ponderosa pine canopy cover and sugar maple crown damage was analyzed. Measurement precision (root mean square of differences in replicate measurements) of pine canopy cover was high (+or-2.6-4.0%) was similar for field replicates and laboratory replicates digitized with the same and different f-stops. In contrast, significant systematic errors can be introduced during certain analyses of hemispherical photographs. Measurement precision (frequency of remeasurement within +or- 1 class) of maple crown ratings was high (74-95%), due mainly to crew training prior to data collection. Precision was highest for branch dieback and foliage transparency and when remeasurements were done by the same crew. The following procedures are recommended: implement training prior to data collection, use consistent methods and reference materials to control measurement errors during data collection, and include methods and quality control data for a basis for evaluating data quality for comparability.
"Paper presented at the 'Effetcs of Air Pollution on Western Forests' Symposium (82nd AWMA Annual Meeting in Anaheim, CA, June 29-30, 1989.). Includes bibliographical references. "EPA/600/D-89/105"--Cover. Microfiche.