Sediment deposit ages inferred from radiocarbon dating of stream bank material were used to estimate residence times of valley-floor deposits in headwater valleys of the Oregon Coast Range, USA. Inherited ages of radiocarbon-dated material, i.e., time between carbon fixation in wood and its incorporation in a sediment deposit, can result...
Surface sediment transport is an important geomorphic process which can be significantly altered by management activities in forested ecosystems. Disturbance of the soil surface may result in increased sediment delivery to fish bearing streams and degradation of soil structure. Selective thinning and low impact yarding techniques were utilized in an...
Growing emphasis on ecosystem and landscape-level forest management across North America has spurred an examination of alternative management strategies which focus on emulating dynamic natural disturbance processes, particularly those associated with forest fire regimes. This topic is the cornerstone of research in the Blue River Landscape Study (BRLS) taking place...
Mixed-severity fire occurrence is increasingly recognized in Pseudotsuga forests of the Pacific Northwest, but questions remain about how tree mortality varies, and forest structure is altered, across the disturbance gradient observed in these fires. Therefore, we sampled live and dead biological legacies at 45 one ha plots, with four 0.10...
Reservoir systems in the western US are managed to serve two main competing purposes: to reduce flooding during the winter and spring, and to provide water supply for multiple uses during the summer. Because the storage capacity of a reservoir cannot be used for both flood damage reduction and water...
This study investigates patterns of physical structure organization in stream
networks. In particular, it seeks to describe patterns of wood, boulders, pools and slope
that are evident in stream channels and to determine whether patterns of these elements
are influenced by network-level controls. The four in-stream parameters were
combined to...
About 7,000 years ago two major tephra-falls blanketed the
Pacific Northwest in volcanic ash. These two tephra-falls, identified
as the Llao and climatic tephra-falls, were a part of the eruptive
events that led up to the collapse of Mount Mazama to form Crater Lake
in the southern Oregon Cascades.
The...
Fire is the dominant disturbance process in western U.S. forests, and although effects of fire in upland forests are relatively well-studied, there is little information about fire effects on riparian forests, critical areas of the landscape for both habitat and water quality. This dissertation examines different aspects of fire effects...
An F₁ population resulting from mating pygmy and normal goats (local commercial breeds) was crossed to give an F₂ population. Analysis of wither height and body weight indicated that the F₂ population was intermediate between the parental types (pygmy and normal) with little overlap of phenotypic values for body size...