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Full-Text Articles in Life Sciences

Experimental Evidence For Drought Induced Alternative Stable States Of Soil Moisture, David A. Robinson, Scott B. Jones, Inma Lebron, Sabine Reinsch, Maria T. Dominguez, Andrew R. Smith, Davey L. Jones, Miles R. Marshall, Bridget A. Emmett Jan 2016

Experimental Evidence For Drought Induced Alternative Stable States Of Soil Moisture, David A. Robinson, Scott B. Jones, Inma Lebron, Sabine Reinsch, Maria T. Dominguez, Andrew R. Smith, Davey L. Jones, Miles R. Marshall, Bridget A. Emmett

Plants, Soils, and Climate Faculty Publications

Ecosystems may exhibit alternative stable states (ASS) in response to environmental change. Modelling and observational data broadly support the theory of ASS, however evidence from manipulation experiments supporting this theory is limited. Here, we provide long-term manipulation and observation data supporting the existence of drought induced alternative stable soil moisture states (irreversible soil wetting) in upland Atlantic heath, dominated by Calluna vulgaris (L.) Hull. Manipulated repeated moderate summer drought, and intense natural summer drought both lowered resilience resulting in shifts in soil moisture dynamics. The repeated moderate summer drought decreased winter soil moisture retention by ∼10%. However, intense summer drought, …


Role Of The Strengthened El Nino Teleconnection In The May 2015 Floods Over The Southern Great Plains, S.-Y. Wang, W.-R. Huang, H.-H. Hsu, R. R. Gillies Oct 2015

Role Of The Strengthened El Nino Teleconnection In The May 2015 Floods Over The Southern Great Plains, S.-Y. Wang, W.-R. Huang, H.-H. Hsu, R. R. Gillies

Plants, Soils, and Climate Faculty Publications

The climate anomalies leading to the May 2015 floods in Texas and Oklahoma were analyzed in the context of El Niño teleconnection in a warmer climate. A developing El Niño tends to increase late-spring precipitation in the southern Great Plains, and this effect has intensified since 1980. Anthropogenic global warming contributed to the physical processes that caused the persistent precipitation in May 2015: Warming in the tropical Pacific acted to strengthen the teleconnection toward North America, modification of zonal wave 5 circulation that deepened the stationary trough west of Texas, and enhanced Great Plains low-level southerlies increasing moisture supply from …


Interdisciplinary Modeling For Water-Related Issues Graduate Course, Laurel Saito, Alexander Fernald, Timothy Link Jul 2015

Interdisciplinary Modeling For Water-Related Issues Graduate Course, Laurel Saito, Alexander Fernald, Timothy Link

All ECSTATIC Materials

The science and management of aquatic ecosystems is inherently interdisciplinary, with issues associated with hydrology, atmospheric science, water quality, geochemistry, sociology, economics, environmental science, and ecology. Addressing water resources issues in any one discipline invariably involves effects that concern other disciplines, and attempts to address one issue often have consequences that exacerbate existing issues or concerns, or create new ones (Jørgensen et al. 1992; Lackey et al. 1975; Straskraba 1994) due to the strongly interactive nature of key processes (Christensen et al. 1996). Thus, research and management of aquatic ecosystems must be interdisciplinary to be most effective, but such truly …


Machine Learning For Predicting Soil Classes In Three Semi-Arid Landscapes, Colby W. Brungard, Janis L. Boettinger, Michael C. Duniway, Skye A. Wills, Thomas C. Edwards Jr. Feb 2015

Machine Learning For Predicting Soil Classes In Three Semi-Arid Landscapes, Colby W. Brungard, Janis L. Boettinger, Michael C. Duniway, Skye A. Wills, Thomas C. Edwards Jr.

Plants, Soils, and Climate Faculty Publications

Mapping the spatial distribution of soil taxonomic classes is important for informing soil use and management decisions. Digital soil mapping (DSM) can quantitatively predict the spatial distribution of soil taxonomic classes. Key components of DSM are the method and the set of environmental covariates used to predict soil classes. Machine learning is a general term for a broad set of statistical modeling techniques. Many different machine learning models have been applied in the literature and there are different approaches for selecting covariates for DSM. However, there is little guidance as to which, if any, machine learning model and covariate set …


Response Of Stomatal Density And Bound Gas Exchange In Leaves Of Maize To Soil Water Deficit, Wensai Zhao, Yonglin Sun, Roger Kjelgren, Xiping Liu Jan 2015

Response Of Stomatal Density And Bound Gas Exchange In Leaves Of Maize To Soil Water Deficit, Wensai Zhao, Yonglin Sun, Roger Kjelgren, Xiping Liu

Plants, Soils, and Climate Faculty Publications

Stomatal behavior in response to drought has been the focus of intensive research, but less attention has been paid to stomatal density. In this study, 5-week-old maize seedlings were exposed to different soil water contents. Stomatal density and size as well as leaf gas exchange were investigated after 2-, 4- and 6-weeks of treatment, which corresponded to the jointing, trumpeting, and filling stages of maize development. Results showed that new stomata were generated continually during leaf growth. Reduced soil water content significantly stimulated stomatal generation, resulting in a significant increase in stomatal density but a decrease in stomatal size and …


Registration Of ‘Newell’ Smooth Bromegrass, K P. Vogel, R B. Mitchell, B L. Waldron, M R. Haferkamp, J D. Berdahl, D D. Baltensperger, Galen Erickson, T J. Klopfenstein Dec 2014

Registration Of ‘Newell’ Smooth Bromegrass, K P. Vogel, R B. Mitchell, B L. Waldron, M R. Haferkamp, J D. Berdahl, D D. Baltensperger, Galen Erickson, T J. Klopfenstein

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Warming, Competition, And Bromus Tectorum Population Growth Across An Elevation Gradient, Aldo Compagnoni, Peter B. Adler Sep 2014

Warming, Competition, And Bromus Tectorum Population Growth Across An Elevation Gradient, Aldo Compagnoni, Peter B. Adler

Green Canyon Environmental Research Area, Logan Utah

Cheatgrass (Bromus tectorum) is one of the most problematic invasive plant species in North America and climate change threatens to exacerbate its impacts. We conducted a two‐year field experiment to test the effect of warming, competition, and seed source on cheatgrass performance across an elevation gradient in northern Utah. We hypothesized that warming would increase cheatgrass performance, but that warming effects would be limited by competing vegetation and by local adaptation of cheatgrass seed sources. The warming treatment relied on open top chambers, we removed vegetation to assess the effect of competition from neighboring vegetation, and we reciprocally …


Warming, Soil Moisture, And Loss Of Snow Increase Bromus Tectorum’S Population Growth Rate, Aldo Compagnoni, Peter B. Adler Jan 2014

Warming, Soil Moisture, And Loss Of Snow Increase Bromus Tectorum’S Population Growth Rate, Aldo Compagnoni, Peter B. Adler

Green Canyon Environmental Research Area, Logan Utah

Climate change threatens to exacerbate the impacts of invasive species. In temperate ecosystems, direct effects of warming may be compounded by dramatic reductions in winter snow cover. Cheatgrass (Bromus tectorum) is arguably the most destructive biological invader in basins of the North American Intermountain West, and warming could increase its performance through direct effects on demographic rates or through indirect effects mediated by loss of snow. We conducted a two-year experimental manipulation of temperature and snow pack to test whether 1) warming increases cheatgrass population growth rate and 2) reduced snow cover contributes to cheatgrass’ positive response to …


Climate Change And Plant Demography In The Sagebrush Steppe, Aldo Compagnoni Jul 2013

Climate Change And Plant Demography In The Sagebrush Steppe, Aldo Compagnoni

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Two New Species Of Trigonotylus (Hemiptera: Heteroptera: Miridae: Stenodemini) From Western Canada And Northwestern United States, G G.E. Scudder, Michael D. Schwartz Jan 2012

Two New Species Of Trigonotylus (Hemiptera: Heteroptera: Miridae: Stenodemini) From Western Canada And Northwestern United States, G G.E. Scudder, Michael D. Schwartz

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Livestock Foraging Behavior In Response To Sequence And Interactions Among Alkaloids, Tannins, And Saponins, Tiffany L. Jensen Jan 2012

Livestock Foraging Behavior In Response To Sequence And Interactions Among Alkaloids, Tannins, And Saponins, Tiffany L. Jensen

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


The Role Of Fine-Scale Habitat Associations In Structuring Spider Assemblages: Determinants Of Spatial Patterns In Community Compostion, Stephanie M. Cobbold Jan 2012

The Role Of Fine-Scale Habitat Associations In Structuring Spider Assemblages: Determinants Of Spatial Patterns In Community Compostion, Stephanie M. Cobbold

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Temperature Increase Effects On Sagebrush Ecosystem Forbs: Exprimental Evidence And Range Manager Perspectives, Hilary Louise Whitcomb Jan 2011

Temperature Increase Effects On Sagebrush Ecosystem Forbs: Exprimental Evidence And Range Manager Perspectives, Hilary Louise Whitcomb

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Effects Of Olfactory And Visual Predators On Nest Success And Nest-Site Selection Of Waterfowl In North Dakota, Jennifer Borgo Dec 2008

Effects Of Olfactory And Visual Predators On Nest Success And Nest-Site Selection Of Waterfowl In North Dakota, Jennifer Borgo

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Terpenes And Carbohydrate Source Influence Rumen Fermentation, Digestibility, Intake, And Preference In Sheep, J. J. Villalba, F. D. Provenza, K. C. Olson Jan 2006

Terpenes And Carbohydrate Source Influence Rumen Fermentation, Digestibility, Intake, And Preference In Sheep, J. J. Villalba, F. D. Provenza, K. C. Olson

Green Canyon Environmental Research Area, Logan Utah

We hypothesized that toxins and nutrients in foods interact to influence foraging behavior by herbivores. Based on this hypothesis we predicted that 1) terpenes in big sagebrush (Artemisia tridentata) influence intake and preference in sheep for diets varying in sources of nonstructural (barley grain) and structural (sugar beet pulp) carbohydrates, and 2) these effects are due to the differential effects of terpenes on fermentation products and apparent digestibility of each class of carbohydrates. Lambs were fed 2 isoenergetic and isonitrogenous diets with varying proportions of the same ingredients (beet pulp- and barley grain-based diet) or offered a choice between the …


Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V2, United States Forest Service Jan 1993

Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V2, United States Forest Service

Environmental Assessments (NV)

No abstract provided.


Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V1, United States Forest Service Jan 1993

Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V1, United States Forest Service

Environmental Assessments (NV)

No abstract provided.


Factors Affecting Anion Movement And Retention In Four Forest Soils, D. W. Johnson, D. W. Cole, H. Van Miegroet, F. W. Horng Jan 1986

Factors Affecting Anion Movement And Retention In Four Forest Soils, D. W. Johnson, D. W. Cole, H. Van Miegroet, F. W. Horng

Watershed Sciences Faculty Publications

Three hypotheses concerning the movement and retention of anions in forest soils were tested in a series of laboratory and field studies on two Tennessee Ultisols with mixed deciduous forest cover and two Washington Inceptisols, one with deciduous (red alder Alnus rubra Bong.) and one with coniferous [Douglas-fir, Pseudotsuga menziesii (Mirb.) Franco] forest cover. The first hypothesis, that sulfate and phosphate retention was related to adsorption to free Fe and Al oxides, which were in turn related to soil parent material and degree of weathering, was not supported by results of laboratory and field studies. The young, relatively unweathered Washington …


Proceedings -- National Wilderness Research Conference: Current Research, United States Department Of Agriculture, Forest Service Jan 1986

Proceedings -- National Wilderness Research Conference: Current Research, United States Department Of Agriculture, Forest Service

Forestry

Includes more than 70 reports of current wilderness research. Papers are organized around nine topics: wilderness resource research, including natural fire, air quality, impacts to soil and vegetation, fish and wildlife, and water; and wilderness user research related to recreational use and user characteristics, attitudes and behavior, benefits, and management concepts and tools.


The Effects Of Ultraviolet-B Radiation On Plant Competition In Terrestrial Ecosystems, Warren G. Gold, Martyn M. Caldwell Jan 1983

The Effects Of Ultraviolet-B Radiation On Plant Competition In Terrestrial Ecosystems, Warren G. Gold, Martyn M. Caldwell

Green Canyon Environmental Research Area, Logan Utah

Evidence regarding the interaction of ultraviolet-B radiation and plant competition in terrestrial ecosystems is examined. The competitive interactions of some species pairs were affected even by ambient solar UV-B radiation when compared to control pairs grown without UV-B. Also, the total shoot biomass of these species pairs was depressed under ambient UV-B. Relatively large increases in UV-B radiation altered the competitive interactions of some species pairs grown in pots under field conditions, but did not affect the total shoot biomass production of those pairs. Recent field experiments have examined the competitive interactions of wheat and wild oat under a simulated …


Effects Of Grazing On Desert Vegetation, B. E. Norton, D. J. Bermant Jan 1979

Effects Of Grazing On Desert Vegetation, B. E. Norton, D. J. Bermant

Memorandum

No abstract provided.


The Impact Of Seed Consumers In A Desert Ecosystem: An Integrated Approach, W. G. Whitford Jan 1979

The Impact Of Seed Consumers In A Desert Ecosystem: An Integrated Approach, W. G. Whitford

Memorandum

No abstract provided.


Gas Exchange Of Sonoran Desert Plants, S. R. Szarek, R. M. Woodhouse Jan 1979

Gas Exchange Of Sonoran Desert Plants, S. R. Szarek, R. M. Woodhouse

Memorandum

No abstract provided.


Clustar And Clustid: Programs For Hierarchical Cluster Analysis, K. A. Marshall, H. C. Romesburg Jan 1979

Clustar And Clustid: Programs For Hierarchical Cluster Analysis, K. A. Marshall, H. C. Romesburg

Memorandum

No abstract provided.


Demography Of Termite Colonies As Related To Various Environmental Factors: Nutritional Biochemistry And Physiology Of Termites, W. L. Nutting, J. P. Lafage Jan 1979

Demography Of Termite Colonies As Related To Various Environmental Factors: Nutritional Biochemistry And Physiology Of Termites, W. L. Nutting, J. P. Lafage

Memorandum

No abstract provided.


Tucson Basin Validation Site Report, J. L. Thames Jan 1979

Tucson Basin Validation Site Report, J. L. Thames

Memorandum

No abstract provided.


Rock Valley Validation Site Report, F. B. Turner Jan 1979

Rock Valley Validation Site Report, F. B. Turner

Memorandum

No abstract provided.


Rodent Seed-Foraging Strategies And Competition With Ants In The Sonoran Desert, J. H. Brown, D. W. Davidson Jan 1979

Rodent Seed-Foraging Strategies And Competition With Ants In The Sonoran Desert, J. H. Brown, D. W. Davidson

Memorandum

No abstract provided.


Comparison Of Biological Processes In Western Deserts, J. Skujins Jan 1979

Comparison Of Biological Processes In Western Deserts, J. Skujins

Memorandum

No abstract provided.


Interactions Of Winter Sheep Grazing And Small Mammal Populations, C. D. Jorgensen Jan 1979

Interactions Of Winter Sheep Grazing And Small Mammal Populations, C. D. Jorgensen

Memorandum

No abstract provided.