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- This guidebook describes Forest Creeks Research Natural Area, a 164-ha (405-ac) area comprising two geographically distinct canyons and associated drainages. The two units have been established as examples of first- to third-order streams originating within a ponderosa pine (Pinus ponderosa) zone. The two riparian areas also represent examples of the mountain alder-redosier dogwood (Alnus incana-Cornus sericea ssp. sericea), and the redosier dogwood-mockorange (Cornus sericea ssp. sericea-Philadelphus lewisii) plant associations.AuthorsReid Schuller, Ron HalvorsonKeywordsSourceGen. Tech. Rep. PNW-GTR-813. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 20 p.Year2010
- Availability of free, high quality Landsat data portends a new era in remote sensing change detection. Using dense (~annual) Landsat time series (LTS), we can now characterize vegetation change over large areas at an annual time step and at the spatial grain of anthropogenic disturbance. Additionally, we expect more accurate detection of subtle disturbances and improved characterization in terms of both timing and intensity. For Landsat change detection in this new era of dense LTS, new detection algorithms are required, and new approaches are needed to calibrate those algorithms and to...AuthorsWarren B. Cohen, Zhiqiang Yang, Robert KennedyKeywordsSourceRemote Sensing of EnvironmentYear2010
- We introduce and test LandTrendr (Landsat-based detection of Trends in Disturbance and Recovery), a new approach to extract spectral trajectories of land surface change from yearly Landsat time-series stacks (LTS). The method brings together two themes in time-series analysis of LTS: capture of short-duration events and smoothing of long-term trends. Our strategy is founded on the recognition that change is not simply a contrast between conditions at two points in time, but rather a continual process operating at both fast and slow rates on landscapes. This concept requires both new...AuthorsRobert Kennedy, Zhiqiang Yang, Warren B. CohenKeywordsSourceRemote Sensing of EnvironmentYear2010
- We examined old bark lesions on Lutz spruce in young stands on the Kenai Peninsula, Alaska, to determine their cause. Distribution of these lesions along lower stems was similar to the distribution of spruce beetle attacks during epidemics. These lesions apparently resulted from unsuccessful attacks by spruce beetles during the late 1980s and early 1990s and appear to be symptomatic of conifer tree resistance reactions to cambial zone injury by Dendroctonus beetles.AuthorsJohn S. Hard, Ken P. ZogasKeywordsSourceNorthwest ScienceYear2010
- Land use change can play a very significant role in climate change mitigation and adaptation, as part of efficient portfolios of many land-related activities. Questions involving forestry’s and agriculture’s potential contributions to climate change mitigation are framed within a national context of increased demands for cropland, forage, and wood products to help feed and house an additional 3 billion people globally by 2050, increased land demand for bioenergy production, and millions of hectares of land needed to house another 125 million U.S. residents by midcentury. Three quite...AuthorsR. J. AligSourceAmerican Journal of Agricultural EconomicsYear2010
- We conducted an online survey (n = 3321) followed by five focus groups with Forest Service employees involved in compliance with the National Environmental Policy Act (NEPA) to explore agency views of how NEPA should be implemented within the agency. We filter these perceptions through the lenses of different functional groups within the agency, each with its own role in agency compliance with NEPA and its own suite of perceived accountabilities. In doing so, we uncover areas of consensus regarding valued practices as well as tensions between employees with different roles in NEPA complianc...AuthorsMarc J. Stern, S. Andrew Predmore, Michael J. Mortimer, David N. SeesholtzKeywordsSourceJournal of Environmental ManagementYear2010
- Fluorescence microscopy is used to compare frequencies of pollen tube penetration in in situ populations of Cypripedium bardolphianumW.W. Smith et Farrer, Cypripedium flavum W.W. Smith, Cypripedium montanum Dougl. ex Lindl., Cypripedium parviflorum Salisbury var. pubescens (Wildenow) O.W. Knight, Cypripedium reginae Walter, and Cypripedium tibeticum Schltr. The average natural (insect-mediated) pollination rates measured over five seasons are wide ranging among the six species (0.08–0.74). However, the pollination rate of hand-manipulated populations (self and/or cross) is significantly...AuthorsRetha Edens-Meier, Nan Vance, Yi-Bo Luo, Peng Li, Eric Westhus, Peter BernhardtKeywordsSourceInternational Journal of Plant Sciences. 171(4): 370-381.Year2010
- Differences in the strength of species-habitat relationships across scales provide insights into the mechanisms that drive these relationships and guidance for designing in situ monitoring programs, conservation efforts and mechanistic studies. The scale of our observation can also impact the strength of perceived relationships between animals and habitat conditions. We examined the relationship between geographic information system (GIS)-based landscape data and Endangered Species Act-listed anadromous Pacific salmon (Oncorhynchus spp.) populations in three subbasins of the Columbia River...AuthorsBlake E. Feist, E. Ashley Steel, David W. Jensen, Damon N.D. SatherKeywordsSourceLandscape Ecology. 25: 727-743Year2010
- We conducted a survey of 3321 Forest Service employees involved in compliance with the National Environmental Policy Act (NEPA) followed by five focus groups to investigate agency views of the purpose of agency NEPA processes and their appropriate measures of success. Results suggest the lack of a unified critical task for Forest Service NEPA processes and that employees’ functions relevant to NEPA influence their views of its meaning. Compared to other agency personnel, members of interdisciplinary teams who carry out most day-to-day NEPA-related tasks placed greater emphasis on minimizing...AuthorsMarc J. Stern, S. Andrew Predmore, Michael J. Mortimer, David N. SeesholtzKeywordsSourceJournal of Environmental Management. 91: 1371-1379Year2010
- Identifying and quantifying relationships among landscape patterns, anthropogenic disturbances, and aquatic ecosystems is a new and rapidly developing approach to riverine ecology. In this review, we begin by describing the policy and management drivers for landscape-scale riverine research and we synthesize the technological advances that have enabled dramatic progress in the field. We then describe the development of landscape-scale riverine research through a series of landmark theoretical and review papers. Focusing on landscape-fish relationships, we consider the degree to which past...AuthorsE. Ashley Steel, Robert M. Hughes, Aimee H. Fullerton, Stefan Schmutz, John A. Young, Michio Fukushima, Susanne Muhar, Michaela Poppe, Blake E. Feist, Clemens TrautweinKeywordsSourceLiving Reviews in Landscape Research. 4:1. 60 pYear2010