Habitat loss causes a reduction in available resources for wildlife, alters the configuration of remaining habitat, and may isolate wildlife populations. White-breasted nuthatches (Sitta carolinensis) are experiencing long-term population declines in the Willamette Valley of Oregon, where they are historically associated with oak woodlands. As secondary cavity-nesters, white-breasted nuthatches may...
Drought resistance among genotypes of Port-Orford-cedar (Chamaecyparis lawsoniana (A. Murr.) Pan., Cupressaceae) seedlings was evaluated both in the field and in the greenhouse. Field water potentials (Ψ) of 5-year-old seedlings were measured at two high-elevation plantation sites where summer drought occurs. Measurements of Ψ were compared to survival two years...
Contingent valuation has been used to elicit values
for changes in the quantity and quality of nonmarket
amenities. Yet hypothetically trading dollars for
environmental improvements is not a familiar activity for
most survey respondents. A variety of response effects
associated with survey collected data can potentially lead
to biased contingent...
Abstract:
Resource managers and policy face challenges in forecasting the demand for natural resources replenishment (where possible) of natural resources due to changes in human lifestyle, population change and economic development. The year 2020 demonstrated this challenge on several fronts, including the realm of natural resources. Additionally, much competition for...
The eddy-covariance method often underestimates fluxes under stable, low-wind conditions at night when turbulence is not well developed. The most common approach to resolve the problem of nighttime flux underestimation is to identify and remove the deficit periods using friction-velocity (u*) threshold filters (u*[superscript Th]). This study modifies an accepted...
This study presents the theoretical background necessary to model the bearing capacity of shallow and deep foundations in partially saturated soils. The conventional bearing capacity equations for shallow and deep foundations and the 𝛽-method for deep foundation side resistance have been modified to include the effects of matric suction and...
Forest management is typically associated with a high degree of uncertainty, since it relies on predictions of natural growth processes over long periods of time. A number of methods exist for mitigating the risk associated with this uncertainty, but few have the ability to explicitly minimize risk. This study will...
Whole ecosystem carbon dioxide (CO₂) exchange estimated with the eddy covariance (EC) technique has been central to studies on the responses of terrestrial ecosystems to disturbance and intra‐annual and interannual variations in climate, but challenges exist in understanding and reducing the uncertainty in estimates of net ecosystem exchange (NEE) of...
The present study uses normalized profit function and adaptive expectation approaches to analyze U.S. catfish farm supply. Empirical estimations give short-run supply elasticity of 0.25 and 0.26 and long-run supply elasticity of 0.47 and 2.1 in each of the two approaches, respectively. Technological improvement is attributed for only 9.8% out...