Strongly bimodal, basalt-rhyolite volcanism of the High Lava Plains Province of Oregon followed the Middle Miocene flood basalts of the Pacific Northwest and extends to recent time. During the 8 m.y. of volcanism recorded in the central High Lava Plains, in western Harney Basin, three distinct mafic magmatic trends originate...
Hydrothermal vents appear to be the tip of the subsurface biosphere in the ocean crust. The primary prducers in this biosphere are prokaryotes that tolerate a wide variety of physical and chemical conditions and are versatile in their use of inorganic compounds to drive metabolism. A synthesis of chemical and...
The radiolytic changes in oxidation state for solutions of initially Np(V) and/or Np(VI) were investigated by gamma-irradiation in conjunction with UV/Vis spectroscopy of the aqueous phase. Samples were irradiated in varying concentrations of nitric acid, and with or without the presence of 30 % TBP in dodecane. At short irradiation...
We investigate the utility of adding a 365 nm ultraviolet (UV) light source to the ExoMars panoramic camera (PanCam) scheduled for launch in 2013. The modification makes it feasible to monitor rover drill cuttings for aromatic organic molecules and provide constraints on polycyclic aromatic hydrocarbons (PAH) as a function of...
Distinct aggregations of fungal hyphae and rhizomorphs, or "mats", formed by some genera of ectomycorrhizal (EcM) fungi are common features of soils in coniferous forests of the Pacific Northwest. We measured in situ respiration rates of Piloderma mats and neighboring non-mat soils in an old-growth Douglas-fir forest in western Oregon...
We analyzed 7 years (2002–2008) of micrometeorological and concurrent biological
observations of carbon and water fluxes at a mature ponderosa pine forest in central
Oregon in a semiarid climate. We sought to evaluate the extent that gross primary
productivity, net ecosystem exchange, ecosystem respiration, net primary productivity, net
ecosystem productivity,...
During Leg 168 of the Ocean Drilling Program, basalts were recovered by drilling and subsurface water was collected with a water sampling tool at Hole 1026B on the east flank of Juan de Fuca Ridge. Microorganisms were found in both types of samples. The microorganisms in the basalt appear to...
Many obligate symbiotic fungi are difficult to maintain in culture, and there is a growing need for alternative approaches to obtaining tissue and subsequent genomic assemblies from such species. In this study, the genome of Elaphomyces granulatus was sequenced from sporocarp tissue. The genome assembly remains on many contigs, but...
The ability to estimate and monitor standing dead trees (snags) has been difficult due to their irregular and sparse distribution, often requiring intensive sampling methods to obtain statistically significant estimates. This study presents a new method for estimating and monitoring snags using neighborhood attribute filtered airborne discrete-return lidar data. The...
Amphorophora agathonica (Hottes) is the primary vector of aphid-transmitted viruses in red raspberry in the Pacific Northwest region of the United States. To better understand the biology of the aphid, we estimated the lower developmental threshold and studied the seasonal activity of A. agathonica in commercial fields in northern Washington...