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- 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
- 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
- The Valles Caldera National Preserve (VCNP), which consists of a large, 1.2- to 1.6-million-year-old volcanic caldera, forms the heart of the Jemez Mountains in north-central New Mexico (Figure 1). Known as the Valles Caldera, this bowl-shaped hollow is an especially treasured place within this beloved mountainous landscape for many residents of the region. Its valles (valleys), cerros (hills), and slopes of its encircling mountains are largely contained within the 89,900-acre (35,560-hectare) Preserve, which is celebrated by people regionally, nationally and internationally for its scenic...AuthorsKurt F. AnschuetzSourceFinal report - USDA Forest Service Joint Venture Agreement: 07-JV-11221602. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 629 p.Year2014
- Critical assessment of the connection between units of the habitat type system and physiographic, climatic and soil factors in interior western United States land classifications.AuthorsAntonin Kusbach, John D. Shaw, James N. LongKeywordsSourceApplied Vegetation Science. doi: 10.1111/avsc.12121.Year2014
- Due to the recent outbreaks of bark beetles in western U.S.A., research has focused on the effects of tree mortality on forest conditions, such as fuel complexes and stand structure. However, most studies have addressed outbreak populations of bark beetles only and there is a lack of information on the effect of multiple endemic, low level populations of biotic disturbance agents that could influence forest dynamics, fuel heterogeneity, and species composition. Downed woody material, fuel parameters and stand characteristics were assessed in areas of ponderosa pine (Pinus ponderosa)...AuthorsJennifer G. Klutsch, Russell D. Beam, William R. Jacobi, Jose NegronSourceForest Ecology and Management. 315: 63-71.Year2014
- Environmental DNA (eDNA) detection has emerged as a powerful tool for monitoring aquatic organisms, but much remains unknown about the dynamics of aquatic eDNA over a range of environmental conditions. DNA concentrations in streams and rivers will depend not only on the equilibrium between DNA entering the water and DNA leaving the system through degradation, but also on downstream transport. To improve understanding of the dynamics of eDNA concentration in lotic systems, we introduced caged trout into two fishless headwater streams and took eDNA samples at evenly spaced downstream...AuthorsStephen F. Jane, Taylor M. Wilcox, Kevin S. McKelvey, Michael K. Young, Michael K. Schwartz, Winsor H. Lowe, Benjamin H. Letcher, Andrew R. WhiteleySourceMolecular Ecology Resources. 15: 216-227.Year2014
- This study builds a general equilibrium model of ecosystem services, with sectors of the economy competing for use of the environment. The model recognizes that production processes in the real world require a combination of natural and human inputs, and understanding the value of these inputs and their competing uses is necessary when considering policies of resource conservation. We demonstrate the model with a numerical example of the Mississippi-Atchafalaya river basin, in which grain production in the upper basin causes hypoxia that causes damages to the downstream fishing industry....AuthorsTravis WarziniackSourceJournal of the American Water Resources Association. 50(3): 683-695.Year2014
- The Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics and Nitrogen (BEACHON) project seeks to understand the feedbacks and interrelationships between hydrology, biogenic emissions, carbon assimilation, aerosol properties, clouds and associated feedbacks within water-limited ecosystems. The Manitou Experimental Forest Observatory (MEFO) was established in 2008 by the National Center for Atmospheric Research to address many of the BEACHON research objectives, and it now provides a fixed field site with significant infrastructure. MEFO is a mountainous, semi-arid...AuthorsJ. Ortega, A. Turnipseed, A. B. Guenther, T. G. Karl, D. A. Day, D. Gochis, J. A. Huffman, A. J. Prenni, E. J. T. Levin, S. M. Kreidenweis, P. J. DeMott, Y. Tobo, E. G. Patton, A. Hodzic, Y. Y. Cui, P. C. Harley, R. S. Hornbrook, E. C. Apel, R. K. Monson, A. S. D. Eller, J. P. Greenberg, M. C. Barth, P. Campuzano-Jost, B. B. Palm, J. L. Jimenez, A. C. Aiken, M. K. Dubey, C. Geron, J. Offenberg, Michael G. Ryan, Paula J. Fornwalt, S. C. Pryor, F. N. Keutsch, J. P. DiGangi, A. W. H. Chan, A. H. Goldstein, G. M. Wolfe, S. Kim, L. Kaser, R. Schnitzhofer, A. Hansel, C. A. Cantrell, R. L. Mauldin, J. N. SmithKeywordsSourceAtmospheric Chemistry and Physics. 14: 6345-6367.Year2014