Global vegetation models require the photosynthetic parameters, maximum carboxylation capacity (V[subscript cm]), and quantum yield (alpha) to parameterize their plant functional types (PFTs). The purpose of this work is to determine how much the scaling of the parameters from leaf to ecosystem level through a seasonally varying leaf area index...
The regular monitoring of evapotranspiration from satellites has been limited because of discontinuous temporal coverage, resulting in snapshots at a particular point in space and time. We developed a temporal upscaling scheme using satellite-derived instantaneous estimates of evapotranspiration to produce a daily-sum evapotranspiration averaged over an 8-day interval. We tested...
This research was conducted on three study areas on elk winter
ranges in Northeast Oregon. One was on the Starkey Experimental
Forest and Range and the others were in the same vicinity. Plant
appendages, spring and fall defoliation and fall growth of bluebunch
wheatgrass were evaluated in terms of quality...
Research was conducted near the Starkey Experimental Forest and Range in
northeastern Oregon. Effects of defoliating bluebunch wheatgrass (Agropyron
spicatum (Pursh) Scribn. and Smith) to increase the quality of regrowth available on
elk (Cervus elaphus nelsoni) winter range were studied from 1988 through 1990.
Clipping treatments were implemented to condition...
In the face of environmental stressors, change is imperative for species to remain in place. The nature and degree of this change is of great interest, as it sheds light into the ways in which species respond to ecological and habitat change and may continue to respond during periods of...
Pendent Usnea species were collected in western Oregon and examined.
Character states, such as cortex-medulla-axis ratio; fibril length; papilla diameter;
branching patterns; and presence or absence of fibrils, papillae, soredia, isidia; plus
chemistry, were recorded and analyzed by inspection for differences. Historical
names were researched in the literature. A comparison...
Changes in glacier length reflect the integrated response to local fluctuations in temperature and precipitation, but when do such changes indicate forced climate change, and when do they indicate natural variability? In this study, we simulate the past ~1000 years of glacier length variability across the globe using the 3-stage...
It is well established that individual organisms can acclimate and adapt to temperature to optimize their functioning. However, thermal optimization of ecosystems, as an assemblage of organisms, has not been examined at broad spatial and temporal scales. Here, we compiled data from 169 globally distributed sites of eddy covariance and...