Few landscapes are immune to invasion by exotic plant species. The forested landscape in the western Cascade Range of Oregon appears to have some barriers to invasion, but the extensive road network provides a corridor and habitat for a suite of exotic species to enter and become established. This study...
Throughout the 20th century, windthrow has affected forests in the Bull Run watershed, a 26,500 ha basin that is the principal water source for the city of Portland, Oregon. Windthrow from storms in 1973 and 1983 was mapped into a geographic information system (GIS) and compared to a 1931 windthrow...
Streamside buffer strips provide numerous benefits to stream ecosystems. The buffer strips create shade, provide shelter for wildlife, act as barriers to logging debris during and after timber harvest, and serve as a continued source of large woody debris. Quantifying woody inputs resulting from windthrow provides managers with estimates for...
Forest roads alter hillslope hydrologic processes by intercepting, concentrating, and rerouting storm runoff. Current road drainage guidelines are based on minimizing erosion and do not take into account the impact of forest roads on hillslope hydrology. This work monitors ditch flow and rainfall for 10 road segments over the course...
This investigation explored how the magnitude, style, and frequency of
channel adjustments vary spatially and over time within a 5th-order mountain
watershed. Historical data sets, including repeated cross section surveys spanning up
to 20 years at five sites on 2nd to 5th-order channels and streamflow records spanning
up to 50...
This study was conducted to describe variation of riparian vegetation in an Oregon Coast Range system according to geomorphic characteristics and in relation to streamflow. Specific objectives of this study were to: I) examine if the vegetation composition and structure of the riparian forest varied among channel-reach morphologies, 2) examine...
By emulating natural disturbances such as wildfire, managers hope to maintain biodiversity in managed forests. Leaving residual (live) trees in harvested areas is key to this strategy. However, the effectiveness of this approach is unknown. I surveyed songbirds in 176 stands in the Rocky Mountains of southeastern British Columbia, Canada,...
Research on the distribution of juvenile salmonids in streams has been dominated by studies examining small areas over short periods. However, information relevant to freshwater influences on population persistence is likely to derive from longer-term, multi-scale studies. Relationships were examined among juvenile anadromous salmonids, their freshwater habitat, and landscape characteristics...
The general objective of this study was to develop
models and datasets that would significantly advance our
ability to assess the current and future effects of global
change on the biosphere. The focus was in two areas: (1)
preparing environmental datasets at regional to small
watershed scales; and (2) developing...