From a landscape ecology perspective, meadows are often seen as landscapes in
transition. Succession and change in meadows may be investigated by considering the
physical and anthropogenic factors that influence the landscape through time. What is
often unknown is how changes occur and how physical and anthropogenic factors
contribute to...
Landscape heterogeneity is thought to differ among farm management types (i.e. organic and conventional), and this difference is hypothesized to result in variations in pest control by natural enemies. However, it is unclear if these variations in pest control are driven by landscape structure or by farm management practices themselves....
The introduction of non-native species often results in fundamental changes in the structure and function of disturbed environments. In the Pacific Northwest (PNW), the introduced seagrass Zostera japonica is rapidly expanding in distribution, impacting stakeholders and public use of the intertidal. Z. japonica’s expansion has prompted a number of different...
Crested wheatgrass (Agropyron cristatum [L] Gaertm), an introduced bunchgrass, has been seeded on over 5 million hectares of degraded rangeland in western North America because it establishes more readily than native bunchgrasses. Because crested wheatgrass stands are associated with native species displacement and low biological diversity, there is substantial interest...
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A BRIEF INTRODUCTION OF THE ECOLOGY OF THE SAGEBRUSH
STEPPE IN SOUTHEASTERN OREGON
Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have led to previous studies (or lack of studies) in the field also dictate the directions of current research. Culture,...
Identifying mechanisms that determine who lives and dies is the first step in developing successful restoration techniques for rare species and endangered habitats. We studied interactions that affect establishment of native plant forbs of conservation concern at the seedling stage to support the theoretical basis for restoration activities in Pacific...
The links between forests, streamflow, and climate are poorly understood. Despite hundreds of studies over the past 60 years, fundamental questions of forests' effects on the hydrologic cycle remain unanswered. The hydrological cycle involves mutually-dependent biological and physical processes that operate at multiple scales of time and space, and this...
This dissertation examines learning driven adaptations in salmon recovery efforts and water resources management in Oregon. The case study utilizes a framework highlighting the connections between human and natural systems. Semi-structured interviews are used to analyze interactions between rural riparian landowners and watershed council staffs living and working in Oregon’s...
Invasion by non-native plants into natural areas is an important component of global change that threatens biodiversity and ecosystem structure and function. Mountains are currently among the least invaded ecosystems, however, these biodiversity hotspots are increasingly under threat of exotic plant invasion. Evaluation of plant species distribution patterns in mountain...
A trait based approach was used to assess impacts of overstory density and thinning on understory vegetation components related to wildlife habitat. The relationship between overstory basal area and understory vegetation for species grouped by traits, such as production of flowers, fleshy-fruit and palatable leaves, was characterized in thinned and...