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- A key function of forest inventory is to detect changes in the area of forest land over time, yet different definitions of forest land are used in different regions of the world. Changes in the definition of forest intended to improve international consistency can affect the ability to quantify true changes over time. The objective of this study was to evaluate the effects of a definitional change from relative stocking to canopy cover on the area classified as forest land and its relationship to species and forest density in California, Oregon, and Washington. Both western Juniper and...AuthorsDavid L. Azuma, Andrew GraySourceEnvironmental Monitoring and AssessmentYear2014
- Rural residential development in forests of Oregon and Washington continues to be a key driver of land use change. This type of development can have a variety of effects on the goods and services forests provide to the region. We used structure density from photo-interpreted points around forest inventory and analysis plots to examine differences in forest attributes with respect to varying development metrics. Our results demonstrate that forest ownership (public vs. private), structure density, and proximity of development are critical factors in explaining variation in forest attributes....AuthorsDave Azuma, Bianca N.I. Eskelson, Joel ThompsonSourceForest Ecology and ManagementYear2014
- Assessing uncertainties in hydrologic models can improve accuracy in predicting future streamflow. Here, simulated streamflows using the Variable Infiltration Capacity (VIC) model at coarse (1/16°) and fine (1/120°) spatial resolutions were evaluated against observed streamflows from 217 watersheds. In particular, the adequacy of VIC simulations in groundwater- versus runoff-dominated watersheds using a range of flow metrics relevant for water supply and aquatic habitat was examined. These flow metrics were 1) total annual streamflow; 2) total fall, winter, spring, and summer season...AuthorsMohammad Safeeq, Guillaume S. Mauger, Gordon Grant, Ivan Arismendi, Alan F. Hamlet, Se-Yeun LeeSourceJournal of Hydrometeorology. 15(6): 2501-2521.Year2014
- Summer streamflows in the Pacific Northwest are largely derived from melting snow and groundwater discharge. As the climate warms, diminishing snowpack and earlier snowmelt will cause reductions in summer streamflow. Most regional-scale assessments of climate change impacts on streamflow use downscaled temperature and precipitation projections from general circulation models (GCMs) coupled with large-scale hydrologic models. Here we develop and apply an analytical hydrogeologic framework for characterizing summer streamflow sensitivity to a change in the timing and magnitude of recharge in...AuthorsMohammad Safeeq, G.E. Grant, S.L. Lewis, M.G. Kramer, B. StaabSourceHydrology and Earth System SciencesYear2014
- Dwarf mistletoes, obligate, parasitic plants with diminutive aerial shoots, have long-term effects on host tree water relations, hydraulic architecture and photosynthetic gas exchange and can eventually induce tree death. To investigate the long-term (1886–2010) impacts of dwarf mistletoe on the growth and gas exchange characteristics of host western hemlock, we compared the diameter growth and tree-ring cellulose stable carbon (C) and oxygen (O) isotope ratios (δ13Ccell, 18Ocell) of heavily infected and uninfected trees. The relative basal area growth of infected trees was significantly...AuthorsD. E. Marias, F. C. Meinzer, D. R. Woodruff, D. C. Shaw, S. L. Voelker, Steven W. Oak, William Otrosina, William D. Smith, Kamal J.K. GandhiKeywordsSourceTree PhysiologyYear2014
- The recent explosion of online journals has lead some researchers, scientist and academics to reconsider their traditional venues for publishing research. These on-line journals have the potential for quickly disseminating research, but they also present lots of uncertainty, confusion, and pitfalls for researchers. Many academics search out journals with the high impact factors or short review time for publications.AuthorsRobert DealSourceNorthwest ScienceYear2014
- Forest understory vegetation is influenced by broad-scale variation in climate, intermediate scale variation in topography, disturbance and neighborhood interactions. However, little is known about how these multi-scale controls interact to influence observed spatial patterns. We examined relationships between the aggregated cover of understory plant species (%CU) and multi-scale controls using a largescale experiment including treatments of low (LS), moderate (MS) and variable (VS) disturbance severity replicated in second-growth Douglas-fir (Pseudotsuga meziesii)–western hemlock (Tsuga...AuthorsJulia I. Burton, Lisa M. Ganio, Klaus J. PuettmannKeywordsSourceEcosphereYear2014
- There is a general assumption that intraspecific populations originating from relatively arid climates will be better adapted to cope with the expected increase in drought from climate change. For ecologically and economically important species, more comprehensive, genecological studies that utilize large distributions of populations and direct measures of traits associated with drought-resistance are needed to empirically support this assumption because of the implications for the natural or assisted regeneration of species. We conducted a space-for-time substitution, common garden...AuthorsSheel Bansal, Constance A. Harrington, Peter Gould, J. Bradley St.ClairSourceGlobal Change BiologyYear2014
- The volume of publically available geospatial data on the web is rapidly increasing due to advances in server-based technologies and the ease at which data can now be created. However, challenges remain with connecting individuals searching for geospatial data with servers and websites where such data exist. The objective of this paper is to present a publically available Geospatial Search Engine (GSE) that utilizes a web crawler built on top of the Google search engine in order to search the web for geospatial data. The crawler seeding mechanism combines search terms entered by users with...AuthorsChristopher Bone, Alan Ager, Ken Bunzel, Lauren TierneyKeywordsSourceInternational Journal of Digital EarthYear2014
- Ecosystem services, fundamental to livelihoods and well-being, are reshaping environmental management and policy. However, the behavioral dimensions of ecosystem services and the responses of ordinary people to the management of those services, is less well understood. The ecosystem services framework lends itself to understanding the relationship between ecosystems and human behavior. Ecosystem services, according to the psychological theory of motivational functionalism, are motivations—the personal and social processes that initiate, direct and sustain human action. Thus, how people...AuthorsStanley T. Asah, Anne D. Guerry, Dale Blahna, Joshua J. LawlerKeywordsSourceEcosystem Services. 10: 180-186.Year2014