Methodologies that detect biologically active substances have important potential applications for medical diagnostics, drug discovery, and chemical and biological anti-terrorism efforts. The wide spectrum of potential analytes that induce a physiological response dictates that novel techniques be developed to more rapidly screen and characterize agents that are more economical and...
Understanding the drivers of species occurrence is a fundamental goal in basic and applied ecology. Occupancy models have emerged as a popular approach for inferring species occurrence because they account for problems associated with imperfect detection in field surveys. Current models, however, are limited because they assume covariates are independent...
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Understanding the drivers of species occurrence is a fundamental goal in basic and applied ecology. Occupancy models have emerged as a popular approach for inferring species occurrence because they account for problems associated with imperfect detection in field surveys. Current models, however, are limited because they assume covariates are independent...
Full Text:
Methods & Research R-253:226–284.
Pearl, J. 2000. Causality. Cambridge, New York.
Preston, D. L., J. S
Understanding the drivers of species occurrence is a fundamental goal in basic and applied ecology. Occupancy models have emerged as a popular approach for inferring species occurrence because they account for problems associated with imperfect detection in field surveys. Current models, however, are limited because they assume covariates are independent...
Describing the mechanisms that drive variation in species interaction strengths is central to understanding, predicting, and managing community dynamics. Multiple factors have been linked to trophic interaction strength variation, including species densities, species traits, and abiotic factors. Yet most empirical tests of the relative roles of multiple mechanisms that drive...
High-elevation aquatic ecosystems are highly vulnerable to climate change, yet relatively few records are available to characterize shifts in ecosystem structure or their underlying mechanisms. Using a long-term data set on seven alpine lakes (3126 to 3620 m) in Colorado, USA, we show that ice-off dates have shifted 7 days earlier over...
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, Diane M. McKnight2,4, Mark W. Williams2,3, 7
Katherina Hell2, Matthew P. Miller5, Sarah J. Hart3
High-elevation aquatic ecosystems are highly vulnerable to climate change, yet relatively few records are available to characterize shifts in ecosystem structure or their underlying mechanisms. Using a long-term data set on seven alpine lakes (3126 to 3620 m) in Colorado, USA, we show that ice-off dates have shifted 7 days earlier over...
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Citation:
Preston, D. L., N. Caine, D. M. McKnight,
M. W. Williams, K. Hell, M. P. Miller,
S. J. Hart, and
High-elevation aquatic ecosystems are highly vulnerable to climate change, yet relatively few records are available to characterize shifts in ecosystem structure or their underlying mechanisms. Using a long-term data set on seven alpine lakes (3126 to 3620 m) in Colorado, USA, we show that ice-off dates have shifted 7 days earlier over...
Numerous tests were applied to rainbow trout
of eleven months of age to determine whether
ascorbic acid is an essential element of the diet
of these fish. Although previous work had been
done on this question, conflicts in the results,
the large reliance upon abnormal symptoms such as
lordosis and...
Reduction of pocket gopher damage to conifer seedlings is important to successful reforestation in many regions of the Pacific
Northwest. The objective of this study was to determine the factors that influence the local distribution of the northern pocket gopher (Thomomys talpoides Richardson) in a forested region of south-central Oregon....
The role of each habitat fish use is of great importance to the dynamics of populations. During
their early marine residence, Chinook salmon (Oncorhynchus tshawytscha), an anadromous fish
species, mostly inhabit estuaries but also use sandy beach surf zones and the coastal ocean.
However, the role of surf zones in...
Large quantities of smaller diameter materials are available in the overstocked forests of eastern Oregon and Washington, but the costs of removing these materials and the long distances from markets sharply reduce the potential of this resource. Failure to thin these forests will sharply increase the likelihood of catastrophic wildfires....
The inter-relationships among δ¹³C and δ¹⁸O in tree ring cellulose and ring width have the potential to illuminate long-term physiological and environmental information in forest stands that have not been monitored. We examine how within-stand competition and environmental gradients affect ring widths and the stable isotopes of cellulose. We utilize...
The wine grape industry is rapidly growing in Oregon. By the year 2005, we could predict that Oregon will have over 10,000 acres in wine grape production. At a meeting last year, the Grapevine Improvement Committee acknowledged that little was known about the presence of potential pest and beneficial insects...
The behavior of low-frequency baroclinic Rossby wave motion in the vicinity of coastal boundaries is investigated using linearized modulated wave theory in a stratified, constant-depth, equatorial β-plane ocean. A primary objective is to obtain an equation that describes large-scale, low-frequency pressure fluctuations along variable geometry ocean boundaries at all latitudes...
The Northwest Lau Backarc Basin, consisting of the Northwest Lau Spreading Center (NWLSC) and the Rochambeau Rifts (RR), is unique in having elevated ³He/⁴He ratios (up to 28 R[subscript a]) in the erupted lavas, clearly indicating a hot spot or ocean island basalt (OIB)-type signature. This OIB-type helium signature does...