The effects of fire severity on post-fire succession and shrub demography were quantified in shrub-steppe grasslands and subalpine forests in the Hells Canyon of the Payette National Forest, Idaho. Following the 1988 Eagle Bar Fire, species frequency, community diversity, fire adaptations, and stand ages were quantified at 12 plots in...
Acid deposition and repeated biomass harvest have decreased
soil calcium (Ca) availability in many temperate forests worldwide, yet
existing methods for assessing available soil Ca do not fully characterize
soil Ca forms. To account for discrepancies in ecosystem Ca budgets, it
has been hypothesized that the highly insoluble biomineral Ca...
The subject of this study was the determination of the changes
in photosynthesis, respiration and transpiration in two ecotypes of
Douglas-fir as caused by decreasing soil moisture content. The photosynthetic
rate was also correlated with the relative turgidities of
needles.
All the above processes were greatly affected by decreasing
soil...
Patterns of nest attendance behavior by breeding birds represent a parent-offspring trade-off in which adults balance self-maintenance with parental care decisions.
Incubation, in particular, is of interest because adults must provide an environment
suitable for embryonic development through nest-building and contact-incubation.
We evaluated how adult incubation constancy and nest visitation...
I examined the avian biogeography of the islands of Lago Gatun, Panama, in an effort to better understand the effects of forest fragmentation in this biodiverse region, and specifically to understand the importance of fragment isolation and the mechanism behind its effects on tropical bird distribution. I combined exhaustive surveys...
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William D. Robinson
I examined the avian biogeography of the islands of Lago Gatun
The essays in this collection do not cluster about a specific theme, nor do they present a single unified interpretative approach to issues in the history of American foreign policy. Above all, William Appleman Williams is a teacher. And good teachers are disappointed with conformity. No one would ever come...
The nature and magnitude of experimental errors due to ⁶⁵Zn
adsorption by inorganic surfaces was examined in a laboratory system
designed to measure ⁶⁵Zn uptake by marine phytoplankton. In the pH
range, 6.3±.1 to 7.5±.1, a precipitate formed in the algal nutrient
medium selected for the system. To this seawater-base...
The pulmonary function scores of 250 male cigarette smokers
were compared with 406 lifetime nonsmokers. A Stead-Wells spirometer
was used to obtain forced vital capacity, forced expiratory
flow, forced mid-expiratory flow, and forced expiratory volume. All
individuals included in the sample were between. the ages of 20 and
49 years....
In an effort to describe the plant communities and
succession of the Oregon coastal grasslands, vegetation
and environmental data were collected from 75 stands at
24 separate locations ranging from Cape Falcon in Tillamook
County to Cape Ferrelo in Curry County. The vegetation
data consisted of cover and frequency values...
This study presents potential Low Impact Development (LID) solutions for the Ash Creek watershed and designs several tools to assist localities in implementing the solutions they may choose. Ash Creek is a tributary of the Willamette River flowing through Dallas, Monmouth, and Independence in Polk County, Oregon. Currently, Ash Creek...
This research has addressed an area of outdoor recreation economics which presents difficulties in estimation of demand and valuation. The focus was on visitors to three Columbia River fish
hatcheries, and the net benefits realized from partaking in the recreational/educational experience which fish hatcheries offer. Three characteristics of the recreation...
This research was initiated to investigate the effects of various
parameters on the immune response of juvenile coho salmon to Aeromonas
salmonicida. The antibody response and development of protective
immunity in juvenile coho salmon were followed after a single
intraperitoneal injection of formalin killed A. salmonicida cells emulsified
in Freund's...
Net photosynthesis was measured for photosynthetic light efficiency and capacity on two-year-old plants from eight different seed sources in three measurement periods. The measurement periods corresponded to the physiological periods 1) prior to bud swelling, 2) after needle elongation, and 3) predormancy. Measurement period differences in both photosynthetic efficiency and...
Commercially collected Douglas-fir seed from a moist coastal
ecotype (LaPush, Washington) and a dry inland ecotype (Kaibab
National Forest, Arizona) were subjected to osmotic stresses ranging
from 0 to -8 atmospheres using Carbowax polyethylene glycol 6000
during imbibition and germination. To determine the effect of osmotic
stress on the initiation...
Sapling Douglas-fir trees on five sites in the Coastal and
Cascade Mountain ranges of Oregon were measured five times during
the year from the summer of 1977 through the spring of 1978 for
diurnal patterns of xylem water potential, stomatal conductance and
abscisic acid. Vapor pressure deficit and solar radiation...
Foliage of Douglas-fir seedlings [Pseudotsuga menziesii (Mirb.) Franco] from two contrasting environments was sampled during progressive stages of two consecutive cycles of induced drought for leaf resistance, plant water potential , and abscisic acid content (ABA). One group of seedlings was placed in a controlled environment room while another group...
The early life history stages and metamorphosis in Dover
sole (Microstomus pacificus) are described from 201 larvae and
juveniles. Unlike other pleuronectids, with the possible exception
of the deep-sea sole (Embassichthvs bathvbius), initial migration of
the left eye is not associated with metamorphosis or transition from
plankton to benthos. The...
An understanding of the dynamics of individual tree and stand
growth, development, and structural patterns during the immature
formative years of a commercial species is essential to determine
correct thinning practices necessary to attain desired objectives.
This study compared a natural, medium-site Douglas-fir stand
and an adjacent similar stand released...
Rates of apparent net photosynthesis were measured on a sample
of Rocky Mountain Douglas-fir consisting of eleven one-year-old seedlings
from each of the thirteen different seed sources. Secondary
observations of needle length, needle weight, and needle number
were also obtained. A formula derived through step-wise multiple
regression of the secondary...
When trees from 16 populations of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco. var. menziesii) were grown at ten geographically diverse locations for seven years, those from a Vancouver Island source were among the top three for height growth on nine of the ten plantations (Rowe and Ching, 1974). In contrast, growth...
Collaborative decision-making is often promoted as a means to achieve socially acceptable and enduring solutions to natural resource management issues, and one that holds promise for resolving “wicked” problems. However, success rates for implementation of collaborative recommendations are unknown. This paper explores challenges to collaborative salmon fishery management in Prince...
To bring together in systematic and usable form the bulk of the information dealing with Douglas fir logging costs thus far acquired, so as to make it accessible, is the object of this publication.
A new approach to the discovery of high absorbing semiconductors for solar cells was taken by working under a set of design principles and taking a systemic methodology. Three transition metal chalcogenides at varying states of development were evaluated within this framework. Iron pyrite (FeS₂) is well known to demonstrate...
Composition and structure of Oregon ash
(Fraxinus latifolia) woodlands in the William L. Finley
National Wildlife Refuge, Oregon are described. Twenty
stands dominated by Fraxinus latifolia were sampled with
500 m2 circular macroplots in which floristic microplot
data were collected for plant community synthesis. Plant
communities were identified by computer-assisted...
Processes of metamorphosis, settlement, and growth were examined in Pacific sanddab
using field studies and otolith microstructure. This flatfish transforms at large sizes, has a
gradual metamorphosis, and settles to a nursery on the middle continental shelf. Eye migration
takes 3 months and "metamorphosis proper" which begins after completion of...
The present day vegetation pattern of the Willamette Valley is a result of a long past of human alteration of the landscape. Beginning with aboriginal burning of the grasslands to present day land uses, the vegetation of the valley has been affected by anthropogenic activity. Wet prairie is a vanishing...
This study was divided into two parts. Part I was a quantitative description of some aspects of plant-water relations in Douglas-fir seedlings, and part II was tests of several techniques of screening selected families of Douglas-fir seedlings for drought resistance. Part I. During 20 mild summer days in 1976 at...
As part of investigations to evaluate the suitability of sheep grazing in Douglas-fir (Pseudotsuga menziesii) plantations of Oregon's Coast Range, this research was designed to evaluate the effectiveness of sheep grazing in suppressing unwanted vegetation, determine seasonal variations in forage quality, and investigate the impact of sheep grazing on big...
This study was undertaken to ascertain some of the physiological
effects of the herbicide atrazine on Douglas-fir seedlings.
Photosynthetic and respirational rates were measured on seedlings
grown in a controlled environment chamber. Height and dry weight
increases, shoot/root ratios and percent total nitrogen were obtained
from treated and control seedlings...