Disturbance events strongly affect the composition, structure, and function of forest ecosystems; however, existing US land management inventories were not designed to monitor disturbance. To begin addressing this gap, the North American Forest Dynamics (NAFD) project has examined a geographic sample of 50 Landsat satellite image time series to assess...
Burial Lake sediments from the Noatak Basin in the northwest Brooks Range of Arctic Alaska (68.43°N, 159.17°W, 21.5 m water depth) provide the oldest continuous lacustrine record of paleo-environmental change and paleomagnetic secular variation (PSV) in eastern Beringia. A precise radiocarbon chronology, determined through accelerator mass spectrometry (AMS) allows us...
Plant litter decomposition plays an important role in the global carbon cycle, and contributes large amounts of carbon to soils, which store more carbon than any other terrestrial pool of organic matter. Decomposition plays a fundamental role in nutrient cycling and alters soil properties that shape plant community composition and...
The action of pendant, polyethylene oxide (PEO) brush layers as nonfouling coatings for
biomedical materials is well understood. However progress toward clinical application of stable, high density PEO coatings has historically been impeded by the lack of cost effective, noninvasive methods for their preparation. Triblock polymers featuring a hydrophobic, polypropylene...
Compact storage systems demonstrating increased hydrogen storage capacity are the key to advancing the growth of the hydrogen economy throughout the world and reducing the global dependence on fossil fuels for transportation. The use of highly porous adsorbent materials for reversible hydrogen storage is a promising pathway towards achieving storage...
The causes of the global biodiversity crisis are varied and complex. Anthropogenic threats may act in isolation, or interact additively or synergistically with each other or with natural stressors to affect sensitive taxa. The recent emergence of many infectious diseases in wildlife has brought attention to the role of disease...
The trans-Pacific atmospheric transport of particulate matter (PM)-bound polycyclic aromatic hydrocarbons (PAHs) to remote sites in western North America has been well documented and has triggered research questions regarding to atmospheric transformation of PM-bound PAHs and the potential impacts on human health from their inhalation exposure. In this dissertation, field...
Internal force, or sting, balances are used in wind tunnel testing to measure the total force and moment imposed on an aerodynamic structure. A sting balance operates through strain gauges converting strain from externally applied loads to voltage signals. An accurate measuring device is of paramount importance in wind tunnel...
Prior to November 2010, when The Intertwine Alliance launched the Regional Conservation Strategy (RCS) and Biodiversity Guide (RBG) efforts for the Portland-Vancouver metropolitan region, conservation priorities in the metropolitan region were identified at a broad regional scale that generally excluded urban areas (e.g., state conservation strategies and Willamette Synthesis); were...