This research was designed to broaden the understanding of how timber-harvest affects aquatic macroinvertebrates in perennial and intermittent headwater streams. This study compared emergent and benthic macroinvertebrate assemblages from 20 headwater streams in the central Oregon Coast Range that varied by harvest condition and flow duration. Through comparison of the...
Salmonid run sizes are strongly affected by their early marine stage. Fully understanding the life history of salmonids means understanding how they interact with their marine environment and with other fishes. Changes in the biological and physical environment off the Columbia River region affects the distribution and abundance of predatory...
Natural events such as wildfires, floods, and storms can significantly alter the short-term structure and functioning of natural systems. Recreation in wilderness areas is one instance in which individuals are directly exposed to post-disturbance landscapes. Consequently, public land managers may be faced with a different set of challenges stemming from...
Plate boundaries are commonly regions of complex, diffuse deformation with
the motion across the boundary accommodated by numerous structural systems, rather
than being narrow, discrete zones of deformation. One such boundary occurs where
the North American plate makes contact with Juan de Fuca, Gorda, and Pacific plates
along the west...
Warming of the terrestrial biosphere due to the anthropogenic addition of carbon dioxide to the earth’s atmosphere is becoming a major focus of scientific inquiry. Predictions of the extent of this warming are hampered by uncertainty in the ability of the earth’s ecosystems to counteract this effect by sequestering carbon...
Orchard floor management (OFM) practices can improve soil function and alter
the soil biological community. Soil function is dependent on soil forming materials and
on management practices but little is known about how OFM affect orchard soil quality,
fertilizer N uptake, or tree growth and production.
Research plots were located...
The showy biennial to short-lived perennial Oenothera wolfii (Munz) Raven, Dietrich & Stubbe (Wolf’s evening primrose) occurs in only a small number of isolated populations on the southern Oregon and northern California coast. This rare species is currently listed as Threatened in Oregon, and is considered a Species of Concern...
Belowground carbon (C) storage and quality of soil organic matter (SOM) in
forest soils have implications for sustainable forest management and C sequestration,
but how these pools change in response to management is poorly understood. I
investigated whether fertilization and competing vegetation control, applied alone or
in combination early in...