Species' distributions across the landscape are perhaps the least understood yet most conspicuous features of life on earth. Ecologists have long studied species' distributions; yet, many questions remain about why species occur where they do. Such questions persist largely because species' distributions are complex systems with challenging properties like non-linearity,...
Seven case studies of 11 ecosystems were used to examine the effects of nitrogen-fixing alders in Douglas-fir plantations. The
first case study quantified nitrogen (N) fixation and aboveground net primary production in a young Sitka alder [Alnus sinuata (Regel) Rydb.] ecosystem. At 5 yr of age, the N fixation (C₂2H₂...
Interception of precipitation by forest canopies has been found previously to reduce rainfall intensity, but this effect is poorly understood. The goal of this research is to quantify the attenuation of rainfall intensity by forest canopy interception, with the specific objective of estimating the contribution of this attenuation to hillslope...
This dissertation aims to provide a comprehensive portrayal of doula care in the lives of pregnant and parenting adolescent mothers. The purpose of this research was to examine the relationships between psychosocial stress, social support, institutionalized constraints, and their impacts on health and well-being among adolescent mothers in the Northwestern...
Estimates of potential carbon (C) storage can be used to constrain predictions of future carbon sequestration and to understand the degree to which disturbances, both natural aid anthropogenic, affect C storage. An upper bound on C storage in the Pacific Northwest (PNW) of the United States was estimated using field...
This dissertation explores two economic phenomena involving forest-dependent areas: wage distribution and migration pattern of individuals. Are forest-dependent rural areas less desirable for workers from the standpoint of labor market returns? Are different skills (e.g. education, experience) rewarded differently in these areas? If there are interregional wage differences, would that...
Phylogeographic studies of six Pacific Northwest forest-associated
salamanders provide insight into historical and contemporary processes on
population genetic structure. Among Larch Mountain Salamanders (Plethodon
larselli), cytochrome b mitochondrial (mtDNA) sequences (381 bp) and random
amplified polymorphic DNA (RAPDs; 34 loci) supported separate Management
Units for northern and southern populations (12...
Stocks of salmon are declining in the Pacific Northwest. Based on region-wide studies that list and categorize the status of salmon stocks (Nehlsen et al., 1991; Huntington et al., 1994; and Nawa, 1995), I analyze the watersheds where stocks of salmon spawn for several anthropogenic variables, most of which are...