Point sampling for leaf area index in sagebrush steppe communities
Issue Date
2001-09-01Keywords
angle pinsArtemisia tridentata spp. wyomingensis
leaf angle
artemisia tridentata subsp. vaseyana
artemisia arbuscula
data collection
ground cover
accuracy
steppes
estimation
leaf area index
Idaho
Artemisia tridentata
canopy
artemisia arbuscula
Artemisia tridentata spp. vaseyana
Artemisia tridentata spp. wyomingensis
LAI
low sagebrush
mountain big sagebrush
Wyoming big sagebrush
Metadata
Show full item recordCitation
Clark, P. E., & Seyfried, M. S. (2001). Point sampling for leaf area index in sagebrush steppe communities. Journal of Range Management, 54(5), 589-594.Publisher
Society for Range ManagementJournal
Journal of Range ManagementAdditional Links
https://rangelands.org/Abstract
Although point sampling has been used for more than 30 years to quantify leaf area index (LAI), this field technique has not been rigorously evaluated in sagebrush steppe plant communities. Leaf area index estimates obtained using different sampling pin inclinations or combinations of pin inclinations were evaluated in Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle and Young), low sagebrush (Artemisia arbuscula Nutt.), and mountain big sagebrush (Artemisia tridentata Nutt. ssp. vaseyana [Rydb.] Beetle) communities within the Reynolds Creek Experimental Watershed near Boise, Ida. Leaf area index values determined by clipping and processing green foliage through a leaf area meter were used as evaluation standards. Pins inclined at 13 degrees from the horizontal, used alone or in combination with pins of 52 degrees and/or 90 degrees inclinations, performed poorly for estimating LAI in the Wyoming big sagebrush and low sagebrush communities. Estimating total LAI with either the combination of 52 degrees and 90 degrees angle pins or with 52 degrees or 90 degrees pins alone explained at least 96% of the variability in LAI standard values from the Wyoming big sagebrush and mountain big sagebrush communities. Using 52 degrees angle pins alone produced model fits similar to those obtained when the combination of 52 degrees and 90 degrees angle pins were used to estimate shrub, graminoid, and forb LAI across all 3 communities (P > 0.1). Collecting point data using 52 degrees angle pins often provided better or similar model fits with LAI standards compared to other pin angles but using 90 degrees angle pins offers a better compromise between practicality, efficiency, and accuracy.Type
textArticle
Language
enISSN
0022-409Xae974a485f413a2113503eed53cd6c53
10.2307/4003589
Scopus Count
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