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Displaying 20,201 - 20,210 of 65,202 Publications- 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 a permanent network of sample plots. Although these plots are visited repeatedly through time there are large temporal gaps (e.g. 510 years) between remeasurements such that many forest canopy disturbances go undetected. In this paper we demonstrate how Landsat time series (LTS)...AuthorsTodd A. Schroeder, Sean P. Healey, Gretchen Moisen, Tracey Frescino, Warren B. Cohen, Chengquan Huang, Robert Kennedy, Zhiqiang YangKeywordsSourceRemote Sensing of Environment. 154: 61-73.Year2014
- Inter-comparison and similarity analysis to gauge consensus among multiple simulation models is a critical visualization problem for understanding climate change patterns. Climate models, specifically, Terrestrial Biosphere Models (TBM) represent time and space variable ecosystem processes, for example, simulations of photosynthesis and respiration, using algorithms and driving variables such as climate and land use. While it is widely accepted that interactive visualization can enable scientists to better explore model similarity from different perspectives and different granularity of...AuthorsJ. Poco, A. Dasgupta, Y. Wei, William Hargrove, C. Schwalm, R. Cook, E. Bertini, C. SilvaSourceComputer Graphics ForumYear2014
- Utah's Great Salt Lake (GSL) is a closed-basin remnant of the larger Pleistocene-age Lake Bonneville. The modern instrumental record of the GSL-level (i.e. elevation) change is strongly modulated by Pacific Ocean coupled ocean/atmospheric oscillations at low frequency, and therefore reflects the decadalscale wet/dry cycles that characterize the region. A within-basin network of seven tree-ring chronologies was developed to reconstruct the GSL water year (SeptemberAugust) level, based upon the instrumental record of GSL level from 1876 to 2005. The result was a 576-year reconstruction of...AuthorsR. Justin DeRose, Shih-Yu Wang, Brendan M. Buckley, Matthew F. BekkerKeywordsSourceThe Holocene. 24(7): 805-813.Year2014
- Increasingly, forest management goals include building or maintaining resistance and/or resilience to disturbances in the face of climate change. Although a multitude of descriptive definitions for resistance and resilience exist, to evaluate whether specific management activities (silviculture) are effective, prescriptive characterizations are necessary. We introduce a conceptual framework that explicitly differentiates resistance and resilience, denotes appropriate scales, and establishes the context for evaluation - structure and composition. Generally, resistance is characterized as...AuthorsR. Justin DeRose, James N. LongKeywordsSourceForest Science. 60(6): 1205–1212.Year2014
- The temporal depth and spatial breadth of observations from platforms such as Landsat provide unique perspective on ecosystem dynamics, but the integration of these observations into formal decision support will rely upon improved uncertainty accounting. Monte Carlo (MC) simulations offer a practical, empirical method of accounting for potential map errors in broader ecosystem assessments. However, unless steps are taken across simulations to vary the probability density functions (PDFs) that control simulated map error, the large number of map units to which those PDFs are applied may...AuthorsSean P. Healey, Shawn P. Urbanski, Paul L. Patterson, Chris GarrardKeywordsSourceRemote Sensing of Environment. 150: 207-217.Year2014
- There is a need to identify and develop cost effective harvesting systems for ecosystem restoration projects. In the Western United States, pinyon-juniper woodlands are expanding into sagebrush and rangeland ecosystems. In many areas, this growth negatively impacts water, wildlife habitat, biodiversity, and other resources. In other areas, such as Texas and Oklahoma, expansion of eastern redcedar causes similar concerns for landowners. Treatment of these stems through harvesting has been constrained. It is expensive, and markets are limited. The number of stems per acre, transportation...AuthorsDana Mitchell, John KlepacKeywordsSourceIn: Proceedings of the Global Harvesting TechnologyYear2014
- Management of riparian forests, and how they respond to disturbance, continues to be a focus of interest in the literature. Earlier studies on riparian plant community assembly following harvesting in the boreal forest have focused merely on highly contrasting microhabitats within a landscape, for example, streambank riparian habitat or upland habitat. Sustaining biodiversity and evaluating the success of riparian management requires an understanding of plant community assembly following overstory harvesting across the landscapes, e.g., along the entire riparian-upland gradient, and how...AuthorsRebecca L. MacDonald, Han Y.H. Chen, Brian J. J. Palik, Ellie E. PrepasKeywordsSourceForest Ecology and Management. 312: 138-147.Year2014
- Management of invasive species requires confidence in the detection methods used to assess expanding distributions, as well as an understanding of the dominant modes of spread. Lacking this basic biological information, during early stages of invasion management choices are often driven by available resources and the biology of closely related species. Such has been the case for the management of the phytopathogen, Phytophthora ramorum , causal agent of sudden oak death (SOD) of oaks and tanoaks. To detect P. ramorum , The Oregon SOD eradication program has relied upon the aerial observatio...AuthorsE. Peterson, E. Hansen, J. HulbertKeywordsSourceForest Ecology and Management. 322:48–57Year2014
- We present a 576-year tree-ring-based reconstruction of streamflow for northern Utah's Weber River that exhibits considerable interannual and decadal-scale variability. While the 20th Century instrumental period includes several extreme individual dry years, it was the century with the fewest such years of the entire reconstruction. Extended droughts were more severe in duration, magnitude, and intensity prior to the instrumental record, including the most protracted drought of the record, which spanned 16 years from 1703 to 1718. Extreme wet years and periods are also a regular feature of...AuthorsMatthew F. Bekker, R. Justin DeRose, Brendan M. Buckley, Roger K. Kjelgren, Nathan S. GillKeywordsSourceJournal of the American Water Resources Association (JAWRA). 50(5): 1338-1348.Year2014
- Fuel consumption is an important aspect of the efficiency of timber harvesting. Since loggers are paid based on the weight of wood they produce, it is important to note how many gallons of fuel it takes to produce one ton of wood. An extensive literature review was conducted to evaluate different harvesting systems and the amount of fuel they consumed per unit of wood that they produced. Results showed that varying factors (such as terrain, type of system, and type of cut) led to a variety of differences in fuel consumption. For these reasons a project will be developed to find new...AuthorsJonathan Kenney, Thomas Gallagher, Matthew Smidt, Dana Mitchell, Timothy and McDonaldSourceIn: Proceedings of the Global Harvesting TechnologyYear2014