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Earth Sciences

University of Montana

2014

Articles 1 - 10 of 10

Full-Text Articles in Physical Sciences and Mathematics

A Regional Look At Hanpp: Human Consumption Is Increasing, Npp Is Not, Steven W. Running Nov 2014

A Regional Look At Hanpp: Human Consumption Is Increasing, Npp Is Not, Steven W. Running

Ecosystem and Conservation Sciences Faculty Publications

Abdi et al (2014 Environ. Res. Lett. 9 094003), have adapted the concept of comparing supply and demand of annual plant production known as human appropriation of net primary production (HANPP) to a region of the Sahel with rapid population growth. They found that HANPP more than doubled over the study period of 2000–2010, from 19% to 41%, suggesting increasing vulnerability of these populations to food insecurity.

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Ecogeomorphic Feedbacks And Flood Loss Of Riparian Tree Seedlings In Meandering Channel Experiments, Li Kui, John C. Stella, Anne Lightbody, Andrew C. Wilcox Oct 2014

Ecogeomorphic Feedbacks And Flood Loss Of Riparian Tree Seedlings In Meandering Channel Experiments, Li Kui, John C. Stella, Anne Lightbody, Andrew C. Wilcox

Geosciences Faculty Publications

During floods, fluvial forces interact with riparian plants to influence evolution of river morphology and floodplain plant community development. Understanding of these interactions, however, is constrained by insufficient precision and control of drivers in field settings, and insufficient realism in laboratory studies. We completed a novel set of flume experiments using woody seedlings planted on a sandbar within an outdoor meandering stream channel. We quantified effects on local sedimentation and seedling loss to scour and burial across realistic ranges of woody plant morphologies (Populus versus Tamarix species), densities (240 plants m-2 versus 24 m-2), and sediment …

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Are Local Filters Blind To Provenance? Ant Seed Predation Suppresses Exotic Plants More Than Natives, Dean Pearson, Nadia S. Icasatti, Jose L. Hierro, Benjamin J. Bird Aug 2014

Are Local Filters Blind To Provenance? Ant Seed Predation Suppresses Exotic Plants More Than Natives, Dean Pearson, Nadia S. Icasatti, Jose L. Hierro, Benjamin J. Bird

Biological Sciences Faculty Publications

The question of whether species’ origins influence invasion outcomes has been a point of substantial debate in invasion ecology. Theoretically, colonization outcomes can be predicted based on how species’ traits interact with community filters, a process presumably blind to species’ origins. Yet, exotic plant introductions commonly result in monospecific plant densities not commonly seen in native assemblages, suggesting that exotic species may respond to community filters differently than natives. Here, we tested whether exotic and native species differed in their responses to a local community filter by examining how ant seed predation affected recruitment of eighteen native and exotic plant …

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Analysing The Spatio-Temporal Impacts Of The 2003 And 2010 Extreme Heatwaves On Plant Productivity In Europe, A. Bastos, C. M. Trigo, R. M. Trigo, Steven W. Running Jul 2014

Analysing The Spatio-Temporal Impacts Of The 2003 And 2010 Extreme Heatwaves On Plant Productivity In Europe, A. Bastos, C. M. Trigo, R. M. Trigo, Steven W. Running

Ecosystem and Conservation Sciences Faculty Publications

In the last decade, Europe has been stricken by two outstanding heatwaves, the 2003 event in western Europe and the 2010 episode over Russia. Both events were characterized by record-breaking temperatures and widespread socioeconomic impacts, including significant increments on human mortality, decreases in crop yields and in hydroelectric production. Previous works have shown that an extreme climatic event does not always imply an extreme response by ecosystems. This work attempts to assess how extreme was the vegetation response to the heatwaves during 2003 and 2010 in Europe, in order to quantify the impacts of the two events on carbon fluxes …

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Rapid Reservoir Erosion, Hyperconcentrated Flow, And Downstream Deposition Triggered By Breaching Of 38 M Tall Condit Dam, White Salmon River, Washington, Andrew C. Wilcox, Jim E. O'Connor, Jon J. Major Jun 2014

Rapid Reservoir Erosion, Hyperconcentrated Flow, And Downstream Deposition Triggered By Breaching Of 38 M Tall Condit Dam, White Salmon River, Washington, Andrew C. Wilcox, Jim E. O'Connor, Jon J. Major

Geosciences Faculty Publications

Condit Dam on the White Salmon River,Washington, a 38m high dam impounding a large volume (1.8 million m3) of fine-grained sediment (60% sand, 35% silt and clay, and 5% gravel), was rapidly breached in October 2011. This unique dam decommissioning produced dramatic upstream and downstream geomorphic responses in the hours and weeks following breaching. Blasting a 5 m wide hole into the base of the dam resulted in rapid reservoir drawdown, abruptly releasing ~1.6 million m3 of reservoir water, exposing reservoir sediment to erosion, and triggering mass failures of the thickly accumulated reservoir sediment. Within 90 min …

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Climate And Topographic Controls On Simulated Pasture Production In A Semiarid Mediterranean Watershed With Scattered Tree Cover, J. Lozano-Parra, Marco P. Maneta, S. Schnabel Apr 2014

Climate And Topographic Controls On Simulated Pasture Production In A Semiarid Mediterranean Watershed With Scattered Tree Cover, J. Lozano-Parra, Marco P. Maneta, S. Schnabel

Geosciences Faculty Publications

Natural grasses in semiarid rangelands constitute an effective protection against soil erosion and degradation, are a source of natural food for livestock and play a critical role in the hydrologic cycle by contributing to the uptake and transpiration of water. However, natural pastures are threatened by land abandonment and the consequent encroachment of shrubs and trees as well as by changing climatic conditions. In spite of their ecological and economic importance, the spatiotemporal variations of pasture production at the decadal–century scales over whole watersheds are poorly known.We used a physically based, spatially distributed ecohydrologic model applied to a 99.5 ha …

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A Satellite Data Driven Biophysical Modeling Approach For Estimating Northern Peatland And Tundra Co2 And Ch4 Fluxes, J. D. Watts, John S. Kimball, F. J. W. Parmentier, T. Sachs, J. Rinne, D. Zona, W. Oechel, T. Tagesson, M. Jackowicz-Korczynski, M. Aurela Apr 2014

A Satellite Data Driven Biophysical Modeling Approach For Estimating Northern Peatland And Tundra Co2 And Ch4 Fluxes, J. D. Watts, John S. Kimball, F. J. W. Parmentier, T. Sachs, J. Rinne, D. Zona, W. Oechel, T. Tagesson, M. Jackowicz-Korczynski, M. Aurela

Biological Sciences Faculty Publications

The northern terrestrial net ecosystem carbon balance (NECB) is contingent on inputs from vegetation gross primary productivity (GPP) to offset the ecosystem respiration (Reco) of carbon dioxide (CO2) and methane (CH4) emissions, but an effective framework to monitor the regional Arctic NECB is lacking. We modified a terrestrial carbon flux (TCF) model developed for satellite remote sensing applications to evaluate wetland CO2 and CH4 fluxes over pan-Arctic eddy covariance (EC) flux tower sites. The TCF model estimates GPP, CO2 and CH4 emissions using in situ or remote sensing and reanalysis-based climate data as inputs. …

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Changes To Snowpack Energy State From Spring Storm Events, Columbia River Headwaters, Montana, Zachary M. Seligman, Joel T. Harper, Marco P. Maneta Feb 2014

Changes To Snowpack Energy State From Spring Storm Events, Columbia River Headwaters, Montana, Zachary M. Seligman, Joel T. Harper, Marco P. Maneta

Geosciences Faculty Publications

The generation and release of meltwater during the spring snowmelt season can be delayed because of spring storm episodes with snow accumulation and/or sustained subfreezing temperatures. The delayed release of snowmelt often extends beyond the particular storm event because of changes to the internal state of energy in the snowpack that prevents transmission of meltwater. Following a storm, two energy deficits internal to the snowpack must be overcome before surface melt can drain and exit the snowpack: 1) cold content created by heat lost during the episode must be removed and 2) dry pore space must be filled with liquid …

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Comparison Of Instrumentation To Measure Air And Soil-Surface Temperature Variability In Northern Alaska, Katrina Keleher Jan 2014

Comparison Of Instrumentation To Measure Air And Soil-Surface Temperature Variability In Northern Alaska, Katrina Keleher

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The Circumpolar Active Layer Monitoring (CALM) project has been observing permafrost (perennially frozen ground) and its overlaying active layer (which freezes and thaws annually) in northern Alaska’s Kuparuk River watershed and throughout the polar regions since the mid 1990’s to detect long-term responses to climatic change. The soil-surface temperature data is collected by thermistors that were positioned immediately below the surface of the ground at nine locations within a transect of 1-ha plots arranged from north to south across the region. Locations within each plot were individually selected to represent a full range of microsite conditions, with distinctions in vegetation, …

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Depositional Environment Of The St. Mary River Formation In Western Montana, Stacia M. Martineau Jan 2014

Depositional Environment Of The St. Mary River Formation In Western Montana, Stacia M. Martineau

Undergraduate Theses, Professional Papers, and Capstone Artifacts

In May 2013, the Two Medicine Dinosaur Center (TMDC) began excavation on a dinosaur bonebed in the St. Mary River Formation on Carey Butte, Montana. Since excavation started, four additional bonebeds have been discovered in the surrounding area. They display different depositional environments; two are in sandstone and the other three are in siltstone. The purpose of this study is to provide a depositional setting for the area that links all five sites together comprehensively by examining the sedimentology of the area. A stratigraphic analysis of the St. Mary River Formation of Carey Butte revealed four distinct facies associations. Facies …

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