Insects are important forest disturbance agents, and mapping their effects on tree mortality and surface fuels represents a critical research challenge. Although various remote sensing approaches have been developed to monitor insect impacts, most studies have focused on single insect agents or single locations and have not related observed changes...
Lidar is currently the most accurate method for remote estimation of forest structure, but it has limited spatial and temporal coverage. Conversely, Landsat data are more widely available, but exhibit a weaker relationship with structure under medium to high leaf area conditions. One potentially valuable means of enhancing the relationship...
Improved monitoring of forest biomass and biomass change is needed to quantify natural and anthropogenic effects on the terrestrial carbon cycle. Landsat's temporal and spatial coverage, moderate spatial resolution, and long history of earth observations provide a unique opportunity for characterizing vegetation changes across large areas and long time scales....
Across the western US, the two most prevalent native forest insect pests are mountain pine beetle (MPB; Dendroctonus ponderosae; a bark beetle) and western spruce budworm (WSB; Choristoneura freemani; a defoliator). MPB outbreaks have received more forest management attention than WSB outbreaks, but studies to date have not compared their...
Understanding fine-grain patterns of forest disturbance and regrowth at the landscape scale is critical for effective management, particularly in forests in western Washington, Oregon, and California, U.S., where the policy known as the Northwest Forest Plan (NWFP) was imposed in 1994 over > 8 million ha of forest in an...
Raptors that inhabit sagebrush steppe and grassland ecosystems in the western United States may be threatened by continued loss and modification of their habitat due to energy development, conversion to agriculture, and human encroachment. Actions to protect these species are hampered by a lack of reliable data on such basic...
Studies of anthropogenic impacts on wildlife may produce inconclusive or biased results if they fail to account for natural sources of variation in breeding performance and do not use probabilistic sampling at a scale functional for management. We used stratified random sampling and generalized linear mixed models to test hypotheses...
In 2006–2010, effects of four different cattle stocking rates (0, 14.4, 28.8, and 43.2 animal unit months) were compared, representing 0%, 20%, 32%, and 46% utilization of vegetation by domestic livestock, on vegetation structure (as indexed by visual obstruction), and songbird population and apparent nest density, community composition, and diversity...
Management in fire-prone ecosystems relies widely upon application of prescribed fire and/or fire surrogate (e.g., forest thinning) treatments to maintain biodiversity and ecosystem function. Recently, published literature examining wildlife response to fire and fire management has increased rapidly. However, none of this literature has been synthesized quantitatively, precluding assessment of...
The Northwest Forest Plan (NWFP), which aims to conserve late-successional and old-growth forests (older forests) and associated species, established new policies on federal lands in the Pacific Northwest USA. As part of monitoring for the NWFP, we tested nearest-neighbor imputation for mapping change in older forest, defined by threshold values...
The history of forest change processes is written into forest age and distribution and affects earth systems at many scales. No one data set has been able to capture the full forest disturbance and land use record through time, so in this study, we combined multiple lines of evidence to...
To understand causes and consequences of landscape change, it is often not enough to simply detect change. Rather, the agent causing the change must also be determined. Here, we describe and test a method of change agent attribution built on four tenets: agents operate on patches rather than pixels; temporal...
Although there is acute concern that insect-caused tree mortality increases the likelihood or severity of subsequent wildfire, previous studies have been mixed, with findings typically based on stand-scale simulations or individual events. This study investigates landscape- and regional-scale wildfire likelihood following outbreaks of the two most prevalent native insect pests...
Although there is acute concern that insect‐caused tree mortality increases the likelihood or severity of subsequent wildfire, previous studies have been mixed, with findings typically based on stand‐scale simulations or individual events. This study investigates landscape‐ and regional‐scale wildfire likelihood following outbreaks of the two most prevalent native insect pests...
Although there is acute concern that insect‐caused tree mortality increases the likelihood or severity of subsequent wildfire, previous studies have been mixed, with findings typically based on stand‐scale simulations or individual events. This study investigates landscape‐ and regional‐scale wildfire likelihood following outbreaks of the two most prevalent native insect pests...
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...
Understanding the causes and consequences of rapid environmental change is an essential scientific frontier, particularly given the threat of climate-and land use-induced changes in disturbance regimes. In western North America, recent widespread insect outbreaks and wildfires have sparked acute concerns about potential insect-fire interactions. Although previous research shows that insect...
Grassland and shrubland birds are declining globally due in part to anthropogenic habitat modification. Because population performance of these species is also influenced by non-anthropogenic factors, it is important to incorporate all relevant ecological drivers into demographic models. We used design-based sampling and occupancy models to test relationships of environmental...
Carbon sequestration is increasingly recognized as an ecosystem service, and forest management has a large potential to alter regional carbon fluxes − notably by way of harvest removals and related impacts on net ecosystem production (NEP). In the Pacific Northwest region of the U.S.,
the implementation of the Northwest Forest...
"... One goal of this document is to synthesize the literature on the effects of mechanical thinning on understory plant species. A second goal is to document the effect of prescribed burning on rare, threatened, or endangered species. We review current literature on studies that address effects of prescribed fire...
The ex-vessel supply chain for fisheries has been recognized as an important determinant of value generation. In recent years, as the retail demand for fresh seafood products has increased, many independent fishermen have bypassed thin, monopsonized, or otherwise inferior wholesale markets by engaging in implicit or explicit fixed-output contracts with...
With earth's surface temperature and human population both on the rise a new emphasis has been placed on
monitoring changes to forested ecosystems the world over. In the United States the U.S. Forest Service Forest
Inventory and Analysis (FIA) program monitors the forested land base with field data collected over...
For widely distributed species at risk, such as Pacific salmon (Oncorhynchus spp.), habitat monitoring is both essential and challenging. Only recently have widespread monitoring programs been implemented for salmon habitat in the Pacific Northwest. Remote sensing data, such as Landsat images, are therefore a useful way to evaluate trends prior...
The objectives of this research project are to understand tannin and anthocyanin changes during berry development in Pinot noir fruit and wines. Specifically, the objectives of this research project are:
· Determine the effect of berry development on the composition of tannins in cv. Pinot noir berries
· Determine the...
Rangelands are significant providers of ecosystem services in agroecosystems world‐wide. Yet few studies have investigated how different intensities of livestock grazing impact one important provider of these ecosystem services—native bees. We conducted the first large‐scale manipulative study on the effect of a gradient of livestock grazing intensities on native bees...
Intrinsic and extrinsic factors affect vital rates and population-level processes, and understanding these factors is paramount to devising successful management plans for wildlife species. For example, birds time migration in response, in part, to local and broadscale climate fluctuations to initiate breeding upon arrival to nesting territories, and prolonged inclement...
Intrinsic and extrinsic factors affect vital rates and population-level processes, and understanding these factors is paramount to devising successful management plans for wildlife species. For example, birds time migration in response, in part, to local and broadscale climate fluctuations to initiate breeding upon arrival to nesting territories, and prolonged inclement...
Critical information for evaluating the effectiveness of management strategies for species of concern include distinguishing seldom occupied (or low-quality) habitat from habitat that is frequently occupied and thus contributes substantially to population trends. Using multi-season models that account for imperfect detection and a long-term (1981-2002) dataset on migratory Arctic Peregrine...
Information on land cover at global and continental scales is critical for addressing a range of ecological, socioeconomic and policy questions. Global land cover maps have evolved rapidly in the last decade, but efforts to evaluate map uncertainties have been limited, especially in remote areas like Northern Eurasia. Northern Eurasia...
Published January 1993. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
When characterizing the processes that shape ecosystems, ecologists increasingly use the unique perspective offered by repeat observations of remotely sensed imagery. However, the concept of change embodied in much of the traditional remote-sensing literature was primarily limited to capturing large or extreme changes occurring in natural systems, omitting many more...
A weakness of next-hop routing is that following a link or router failure there may be no routes between some source-destination pairs, or packets may get stuck in a routing loop as the protocol operates to establish new routes. In this article, we address these weaknesses by describing mechanisms to...
Livestock grazing is a widespread source of habitat modification, and may affect populations of ground-nesting grassland birds by influencing rates of nest failure. Nesting attempts can fail for various reasons, and determining risk of failure from specific causes associated with livestock grazing would enhance development of range management practices in...
Rubus seed has a deep double dormancy that restricts germination due to seed coat structure and chemical composition. Improved germination of diverse Rubus species required for breeding improved blackberry and raspberry cultivars is partly dependent on the seed coat structure. This study evaluated the seed coat structure of three species...
The objectives of this research are to monitor tannin and anthocyanin changes during berry development and over several growing seasons to understand how the vintage effects wine composition. Specifically, the objectives of this research project are :
· Determine the effect of berry development on the composition of phenolics (tannins...
• Premise of study: In the mixed evergreen forests in the western United States, Arbutus menziesii is able to quickly resprout following disturbance and, as such, act as a nurse tree during forest regeneration. The mechanism for this nurse tree effect has frequently been ascribed to mycorrhizal fungi, but no...
Knowledge of nutrient pathways and their resulting ecological interactions can alleviate numerous environmental problems associated with nutrient increases in both natural and managed systems. Although not unique, coastal systems are particularly prone to complex ecological interactions resulting from nutrient inputs from both the land and sea. Nutrient inputs to coastal...
Academic and public libraries have begun to purchase e-book readers and make them available for check-out to their users. The nature of the e-books on these devices necessitates new approaches to workflow for acquisitions and cataloging departments. In addition, the application of cataloging rules and conventions presents a number of...
To test the hypothesis that embryogenesis depends upon α-tocopherol (E) to protect embryo polyunsaturated fatty acids (PUFAs) from lipid peroxidation, new methodologies were applied to measure α-tocopherol and fatty acids in extracts from saponified zebrafish embryos. A solid phase extraction method was developed to separate the analyte classes, using a...
Little is known about the impact of temperature on proanthocyanidin (PA) accumulation in grape skins, despite its
significance in berry composition and wine quality. Field-grown grapes (cv. Merlot) were cooled during the day or
heated at night by +/–8 C, from fruit set to veraison in three seasons, to determine...
Juvenile English sole, Parophrys vetulus utilize Yaquina Bay, Oregon, as a nursery during at least a portion of their first year of life, but the possibility of the existence of additional nursery grounds offshore has not previously been examined. During 1971, young-of the-year first appeared in Yaquina Bay in February,...
Potential for large prairie remnants to provide habitat for grassland-obligate wildlife may be compromised by
nonsustainable range-management practices. In 1979–1980, high nesting densities of 3 species of hawks in the genus
Buteo—Ferruginous Hawk (Buteo regalis), Red-tailed Hawk (B. jamaicensis), and Swainson’s Hawk (B. swainsoni)—were
documented on the Zumwalt Prairie and...
The characterization of temporal and spatial distribution of sunlight is essential for understanding energy transport in natural ecosystems. Fiber-optic distributed temperature sensing (DTS) allows meter resolution measurements of temperature at subminute resolution. The difference in temperature due to absorption and reflection of a pair of helically twisted black and white...