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Full-Text Articles in Other Ecology and Evolutionary Biology

A Distributed Intelligence Approach To Multidisciplinarity: Encouraging Divergent Thinking In Complex Science Issues In Society., Jarod Kawasaki, Dai Toyofuku Mar 2013

A Distributed Intelligence Approach To Multidisciplinarity: Encouraging Divergent Thinking In Complex Science Issues In Society., Jarod Kawasaki, Dai Toyofuku

The Transdisciplinary STEAM+ Journal

The scientific issues that face society today are increasingly complex, open-ended and tentative (Sadler, 2004). Finding solutions to these issues, not only requires an understanding of the science, but also, concurrently dealing with political, social, and economic dimensions that exist (Hodson, 2003). For example, 40 years after the first congressional hearing on climate change held by Al Gore in 1976, the 2012 Intergovernmental Panel on Climate Change (IPCC) report states that climate change is still getting worse, despite efforts by governments, businesses, social actors such as Non-Government Organizations, and scientists. With the top minds in the world, across all disciplines, …


Range Maps For Nebraska's Threatened And Endangered Species, Nebraska Natural Heritage Program Jan 2013

Range Maps For Nebraska's Threatened And Endangered Species, Nebraska Natural Heritage Program

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This document includes maps and associated information on the ranges of Nebraska’s federal and state-listed species. The information is current as of January 2013. The information is updated as needed. Contact the Nebraska Game and Parks Commission to determine if a more current version is available. The species treated are as follows: American Burying Beetle (Nicrophorus americanus), Salt Creek Tiger Beetle (Cicindela nevadica lincolniana), Swift Fox (Vulpes velox), River Otter (Lutra canadensis), Southern Flying Squirrel (Glaucomys volans), Pallid Sturgeon (Scaphirhyncus albus), Topeka Shiner (Notropis topeka), Sturgeon Chub (Macrhybopsis gelida), Blacknose Shiner (Notropis heterolepis), Lake Sturgeon (Acipenser fulvescens), Northern Redbelly Dace …


Factors Influencing The Establishment And Survival Of Native Hardwood Tree Seedlings Of The Kentucky Inner Bluegrass Blue Ash-Oak Savanna-Woodland, James D. Shaffer Jan 2013

Factors Influencing The Establishment And Survival Of Native Hardwood Tree Seedlings Of The Kentucky Inner Bluegrass Blue Ash-Oak Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Historically, the Kentucky Inner Bluegrass blue ash-oak savanna-woodland was the primary ecosystem of the Inner Bluegrass Region (IBR) of Kentucky. After European settlement, the majority (>99%) of Bluegrass savanna was converted to agricultural and urban land uses. Currently remnant savanna tree species are failing to recruit. Therefore, a long-term restoration ecology project researching competition and disturbance on seedling establishment, survival, and growth has been established at Griffith Woods (the largest remaining savanna in Kentucky) in Harrison Co., KY. Fourteen native hardwood tree species (a total of 6,168 seedlings) have been experimentally planted. Light, soil, surrounding vegetation, and herbivory, factors …


Review Of Conspecific Attraction And Area Sensitivity Of Grassland Birds, David R.W. Bruinsma, Nicola Koper Oct 2012

Review Of Conspecific Attraction And Area Sensitivity Of Grassland Birds, David R.W. Bruinsma, Nicola Koper

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Many species of grassland birds are area sensitive, which may exacerbate the ecological effects of the extensive loss and fragmentation of grasslands that has taken place across the northern Great Plains. However, the reasons for this area sensitivity are unclear, as vegetation structure, matrix composition, and restriction of movements among patches do not seem to provide viable explanations for species native to grasslands. Con specific attraction, whereby species are behaviorally stimulated to select habitat or establish territories near individuals of the same species, may help explain this area sensitivity. We review and discuss theoretical and empirical research on avian conspecific …


Habitat Use And Abundance Patterns Of Sandhill Cranes In The Central Platte River Valley, Nebraska, 2003–2010, Todd Joseph Buckley Nov 2011

Habitat Use And Abundance Patterns Of Sandhill Cranes In The Central Platte River Valley, Nebraska, 2003–2010, Todd Joseph Buckley

School of Natural Resources: Dissertations, Theses, and Student Research

The Central Platte River Valley (CPRV) in Nebraska is an important spring stopover area for the midcontinent population of sandhill cranes. Alterations to crop rotation and loss habitat in the CPRV pose a risk to the population. Personnel drove designated routes in the CPRV from 2003–2010 to record the presence of cranes in agricultural fields and estimate abundance. I developed and evaluated models to predict habitat use and flock sizes. Alfalfa was predicted to receive the highest use followed by corn, soybeans, winter wheat, grassland, and shrubland. Use of all habitats and flock size increased as field area increased. Flock …


Impact Of Alternative Range Management Systems On Grasslands In The Central Platte River Valley, Nebraska, Luis E. Ramirez Jul 2011

Impact Of Alternative Range Management Systems On Grasslands In The Central Platte River Valley, Nebraska, Luis E. Ramirez

School of Natural Resources: Dissertations, Theses, and Student Research

Land management strategies can directly and indirectly affect plant assemblages and their behavior. Little research has been performed in south central Nebraska to quantify the effect of fire and grazing interactions on species composition, vegetation structure, forage quality, and potential cost associated with land management.

I evaluate the effect of season-long continuous, patch-burning, and rotational grazing approaches on vegetation and ranching costs to determine their value as conservation tools. This study includes data collected between 2007 and 2009 from grasslands in south central Nebraska. I found that land management influence plant assemblages by shifting communities when grazing and/or fire are …


Discontinuities: Predicting Invasions And Extinctions, Aaron Lotz Jul 2011

Discontinuities: Predicting Invasions And Extinctions, Aaron Lotz

School of Natural Resources: Dissertations, Theses, and Student Research

In this dissertation, I explore multiple tenets of the textural discontinuity hypothesis, which states that hierarchical landscape structures with scale-specific pattern entrain attributes of animals inhabiting the landscape. Landscapes form hierarchies that are structured by vegetative, geomorphological and contagious disturbance processes. The spatial and temporal patterns inherent in landscapes reflect numerous processes, interacting on distinct scales, which shape the assembly of animal communities. Analysis of body mass patterns and functional group distributions has been suggested as methods to provide insight about these underlying hierarchical processes. Scientists have posited that species at the edges of body mass aggregations may be exposed …


The Distribution And Life Cycle Of Alliaria Petiolate In Lincoln, Nebraska, Caleb Pharris Jul 2011

The Distribution And Life Cycle Of Alliaria Petiolate In Lincoln, Nebraska, Caleb Pharris

Department of Environmental Studies: Undergraduate Student Theses

Alliaria petiolata (Garlic Mustard) is a biennial alien invasive plant species of the Brassicacea family. It is responsible for displacing native plant species throughout North America and its management has proven to be extremely difficult. Recently several populations of Alliaria petiolata have been discovered in southwestern Lincoln, Nebraska. The spread of Alliaria petiolata is a concern for natural resource managers and the general public. Due to the difficulty of its control, Alliaria petiolata is capable of creating monocultures which diminish the aesthetic value of an ecosystem. While most commonly found in the understory of hardwood forests, it is capable of …


An Assessment Of Stable Hydrogen-Isotope Analysis Methods To Assign Geographic Origin To Migratory Red-Tailed Hawks (Buteo Jamaicensis), Carla Marie Ahlschwede May 2011

An Assessment Of Stable Hydrogen-Isotope Analysis Methods To Assign Geographic Origin To Migratory Red-Tailed Hawks (Buteo Jamaicensis), Carla Marie Ahlschwede

Department of Environmental Studies: Undergraduate Student Theses

Stable-hydrogen isotopes are becoming an increasingly popular method of studying migratory birds, though sample preparation methods may affect results.  In this study I examined feathers from red-tailed hawks (Buteo jamaicensis) to determine the relationship between measure of δD due to inter-feather variation or drying methods, assessed the accuracy of results by using two birds of known-origin and estimated possible natal origins of migratory red-tailed hawks.  Two feathers per individual were taken from 81 wild hawks caught at Hitchcock Nature Center near Crescent IA and from 2 rescued red-tailed hawks, Raptor Recovery Nebraska near Eagle, NE. 119 of the …


Biomass Energy At Colby College, Rachel E. Baron Jan 2011

Biomass Energy At Colby College, Rachel E. Baron

Honors Theses

In light of growing concern regarding the effects of global climate change, Colby College signed the American College and University Presidents’ Climate Commitment (ACUPCC) in 2008. Through this pledge, Colby has committed to reducing carbon emissions in its Climate Action Plan (IPCC 2007; CCAP 2010). The College seeks to be carbon neutral by 2015 (CCAP 2010). This will be accomplished through a variety of mechanisms, one of which includes the construction of a biomass facility to replace most of the oil currently used for heating (CCAP 2010).

Anthropogenic global climate change has been documented by many scientists, but was widely …


Abundance And Stomach Content Analysis Of Threadfin Shad In Lake Mead, Nevada: Do Invasive Quagga Mussels Affect This Prey Species?, Eric Michael Loomis, Jon C. Sjoberg, Wai Hing Wong, Shawn Gerstenberger Jan 2011

Abundance And Stomach Content Analysis Of Threadfin Shad In Lake Mead, Nevada: Do Invasive Quagga Mussels Affect This Prey Species?, Eric Michael Loomis, Jon C. Sjoberg, Wai Hing Wong, Shawn Gerstenberger

Environmental & Global Health Faculty Research

Lake Mead, Nevada is the largest reservoir by volume in the United States, as well as a popular sport fishing destination. In January 2007, the invasive quagga mussel Dreissena rostriformis bugensis (Andrusov, 1897) was discovered in the reservoir and concerns began to arise about potential alterations to the aquatic environment. The Lake Mead sport fishery is reliant on the sustainability of prey species like the threadfin shad [Dorosoma petenense (Günther, 1867)]. This study examined 20-year trends in historic abundance of the threadfin shad, before, and shortly after, the discovery of quagga mussels in the system. Larval shad trawl data collected …


Fire: Ecology & Prevention, Justin R. Frey Jun 2010

Fire: Ecology & Prevention, Justin R. Frey

Social Sciences

No abstract provided.


Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters Jan 2010

Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters

School of Natural Resources: Dissertations, Theses, and Student Research

Invasive plant species are widely recognized as a major threat to biodiversity and ecosystem stability. Wetland ecosystems tend to be much more susceptible to invasions because of their location on the landscape where water, nutrients, and the impacts of disturbances accumulate. Invasive plants have the ability to alter ecosystem processes and community/population dynamics. The ability of invasive plants to alter these processes can have profound economic consequences. In the United States, control of invasive wetland species alone costs approximately 155 million dollars annually. The state of Nebraska spends 2 million dollars annually controlling invasive plant species in the Platte River …


Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood Oct 2009

Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood

Environmental Science and Management Faculty Publications and Presentations

Nutrient uptake capacity is an important parameter in modeling nutrient uptake by plants. Researchers commonly assume that uptake capacity measured for a species can be used across sites. We tested this assumption by measuring the nutrient uptake capacity of intact roots of Engelmann spruce (Picea engelmanni Parry) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) at Loch Vale Watershed and Fraser Experimental Forest in the Rocky Mountains of central Colorado. Roots still attached to the tree were exposed to one of three concentrations of nutrient solutions for time periods ranging from 1 to 96h, and solutions were analyzed for ammonium, …


Progress In Strategic Research Areas, Scott R. Abella Jan 2009

Progress In Strategic Research Areas, Scott R. Abella

Public Policy and Leadership Faculty Research

Three years ago through conversations with resource managers, assessing the status of knowledge of the scientific literature, and our own interests, we set forth several strategic research areas that we believed would be timely for advancing Mojave Desert conservation and management.


Terrapene Ornata (Ornate Box Turtle) Predation On Cliff Swallows, Mary Bomberger Brown, Charles R. Brown Jan 2008

Terrapene Ornata (Ornate Box Turtle) Predation On Cliff Swallows, Mary Bomberger Brown, Charles R. Brown

School of Natural Resources: Faculty Publications

During a 25-year study of Cliff Swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, we observed Terrapene ornata prey, or attempt to prey, on swallows. On one occasion as large numbers of birds flushed and hit the net, the weight of the birds pulled the net down to ground level. One T. ornata, which was seen regularly at the colony, approached one adult Cliff Swallow that was very low in the net and killed it by biting and eating its head. After killing the bird, the turtle walked away carrying the head.


Benthic Mapping For Habitat Classification In The Peconic Estuary: Phase I Groundtruth Studies, Robert M. Cerrato, Nicole P. Maher Oct 2007

Benthic Mapping For Habitat Classification In The Peconic Estuary: Phase I Groundtruth Studies, Robert M. Cerrato, Nicole P. Maher

School of Marine & Atmospheric Sciences Faculty Publications

Benthic habitat maps of the estuary seafloor will increase our knowledge of range and variability in benthic habitats, will assist managers in their efforts to protect and/or restore commercially and recreationally important finfish and shellfish, will link land usage (e.g. developed vs. undeveloped areas) and water quality data to benthic habitat quality, and will make it possible to utilize faunal data as a long-term indicator of the overall “health” of the estuary. We are developing benthic habitat maps by combining high-resolution remote sensing techniques with detailed study of the physical and faunal characteristics at point locations in different seafloor environments. …


Homogenization Of Forest Plant Communities And Weakening Of Species-Environment Relationships Via Agricultural Land Use, Mark Vellend, Kris Verheyen, Kathryn M. Flinn, Hans Jacquemyn, Annette Kolb, Hans Van Calster, George Peterken, Bente Jessen Graae, Jesse Bellemare, Olivier Honnay, Jörg Brunet, Monika Wulf, Fritz Gerhardt, Martin Hermy May 2007

Homogenization Of Forest Plant Communities And Weakening Of Species-Environment Relationships Via Agricultural Land Use, Mark Vellend, Kris Verheyen, Kathryn M. Flinn, Hans Jacquemyn, Annette Kolb, Hans Van Calster, George Peterken, Bente Jessen Graae, Jesse Bellemare, Olivier Honnay, Jörg Brunet, Monika Wulf, Fritz Gerhardt, Martin Hermy

Biological Sciences: Faculty Publications

Disturbance may cause community composition across sites to become more or less homogenous, depending on the importance of different processes involved in community assembly. In north-eastern North America and Europe local (alpha) diversity of forest plants is lower in forests growing on former agricultural fields (recent forests) than in older (ancient) forests, but little is known about the influence of land-use history on the degree of compositional differentiation among sites (beta diversity). Here we analyse data from 1446 sites in ancient and recent forests across 11 different landscapes in north-eastern North America and Europe to demonstrate decreases in beta diversity …


Ecological Correlates Of Buggy Creek Virus Infection In Oeciacus Vicarius, Southwestern Nebraska, 2004, Amy T. Moore, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown Jan 2007

Ecological Correlates Of Buggy Creek Virus Infection In Oeciacus Vicarius, Southwestern Nebraska, 2004, Amy T. Moore, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown

School of Natural Resources: Faculty Publications

Buggy Creek virus (family Togaviridae, genus Alphavirus, BCRV) is an alphavirus within the western equine encephalitis virus complex whose primary vector is the swallow bug, Oeciacus vicarius Horvath (Hemiptera: Cimicidae), an ectoparasite of the colonially nesting cliff swallow, Petrochelidon pyrrhonota, that is also a frequent host for the virus.We investigated ecological correlates of BCRV infection in 100-bug pools at 14 different swallow colony sites in southwestern Nebraska from summer 2004, by using plaque assay on Vero cells to identify cytopathic virus and reverse transcription-polymerase chain reaction to identify noncytopathic viral RNA. We found 26.7% of swallow bug pools …


Types Of Areas And The Origin Of Black Flies Fauna In Mongolia (Diptera: Simuliidae), Josef Halgoš Jan 2005

Types Of Areas And The Origin Of Black Flies Fauna In Mongolia (Diptera: Simuliidae), Josef Halgoš

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The survey of Mongolian Black Flies species (Diptera: Simuliidae) is given in the presented work. The classification based on Emelyanov (1974) and Gorodkov (1984) appeared to be as most advantageous one. Black Flies species found on the Mongolian territory up to now were classified according to the character of their distribution among 5 groups: Holoarctic species (7 species), Eurasian (15), Eastern Palaearctic (20), Turanian-Mediterranean (7), Mongolian endemic species (8). Individual groups are divided according to the type of area into smaller subgroups. The zoogeographical analysis has shown big similarity with Black Flies zoogeography in Siberia and Far East (in percentage …


Reproductive Ecology Of Two Common Woody Species, Juniperus Sabina And Artemisia Santolinifolia, In Mountain Steppes Of Southern Mongolia, Katrin Ronnenberg Jan 2005

Reproductive Ecology Of Two Common Woody Species, Juniperus Sabina And Artemisia Santolinifolia, In Mountain Steppes Of Southern Mongolia, Katrin Ronnenberg

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The present study describes the reproductive ecology of the prostrate shrub Juniperus sabina and the dwarf shrub Artemisia santolinifolia in dry mountain steppes of southern Mongolia. Whereas stands of the juniper are located at the drought limit of the genus’ distributional range, the genus Artemisia is typical of central Asian drylands. Both species produce large numbers of reproductive organs. For Juniperus sabina, however, only 2.5% of the morphologically intact seeds were found to be viable. Correspondingly, neither seedlings nor saplings were found in the field, and recruitment by reseeding happens at most rarely under the present climatic conditions.

Instead, …


Quantitative Investigations On Bird Communities In Different Habitats In The Orkhon-Selenge-Valley In Northern Mongolia, Tobias Stenzel, Michael Stubbe, Ravčigijn Samjaa, Sundev Gombobaatar Jan 2005

Quantitative Investigations On Bird Communities In Different Habitats In The Orkhon-Selenge-Valley In Northern Mongolia, Tobias Stenzel, Michael Stubbe, Ravčigijn Samjaa, Sundev Gombobaatar

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

In the breeding seasons 2001 to 2003, the avifauna of a study area of about 80 km2 in the Selenge Aymag was studied.

The area is characterized by loose groves of elms (Ulmus pumila) and pine trees (Pinus sylvestris), and a chain of barchan dunes which separate the Orkhon valley from the up to 70 m higher situated forest steppe. Steppe species (Stipa spp.) dominate in the south; the northern steppe part is characterized by Caragana bushes (Caragana microphylla, locally C. stenophylla). Between Orkhon Gol and the eastern dunes, dry steppe …


Die Parasitierung Der Luzerne-Blattschneiderbiene, Megachile Rotundata (Hymenoptera: Megachilidae), Durch Physocephala Pusilla (Diptera: Conopidae) In Der Mongolei = Parasitization Of The Alfalfa Leaf-Cutter Bee, Megachile Rotundata (Hymenoptera: Megachilidae), By Physocephala Pusilla (Diptera: Conopidae) In Mongolia, Karsten Seidelmann Jan 2005

Die Parasitierung Der Luzerne-Blattschneiderbiene, Megachile Rotundata (Hymenoptera: Megachilidae), Durch Physocephala Pusilla (Diptera: Conopidae) In Der Mongolei = Parasitization Of The Alfalfa Leaf-Cutter Bee, Megachile Rotundata (Hymenoptera: Megachilidae), By Physocephala Pusilla (Diptera: Conopidae) In Mongolia, Karsten Seidelmann

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Physocephala pusilla Meigen (Diptera: Conopidae) was found to be a dangerous endoparasitoid of the alfalfa leafcutter bee Megachile rotundata F. (Hymenoptera: Megachilidae) in Mongolia. The conopid fly parasitizes adults and causes their early death. In 1989 and 1990, 16% and 15% respectively of the M. rotundata females were found dead in front of the bee shelter. However, the number of bees (females and males) dying in the field is unknown. These bees cause a contamination of the alfalfa fields due to an increase of the conopid population. Therefore, Ph. pusilla becomes a serious problem for the management of M. rotundata …


Natürliche Und Nutzungsbedingte Land- Und Bodendegradationsprozesse, Untersucht Am Unteren Orchon (Nord-Mongolei) = Naturally And Land Use Caused Land And Soil Degradation Processes, Studied At The Lower Orchon (Northern Mongolia), Christian Opp Jan 2005

Natürliche Und Nutzungsbedingte Land- Und Bodendegradationsprozesse, Untersucht Am Unteren Orchon (Nord-Mongolei) = Naturally And Land Use Caused Land And Soil Degradation Processes, Studied At The Lower Orchon (Northern Mongolia), Christian Opp

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Landscape-ecological investigations were carried-out within the forest steppe of Northern Mongolia. The site conditions of the partly by agriculture used area of Cagaan Tolgoj at the Lower Orchon (Aimag Selenge) were analysed in seven test areas. Results of soil analysis are given. The evaluation of soil cover and partly vegetation cover was carried-out with special regard, to degradation phaenomena. It is based on field analysis, measurements during the soil survey and the detection of soil degradation parameter with the help of laboratory analysis. Among naturally and land use caused factors of soil status and of the changing conditions within forest …


Die Gasteromyceten Der Mongolei Und Ihre Bedeutung Für Die Systematik, Chorologie Und Ökologie) = The Mongolian Gasteromycetes And Their Importance For The Systematics, Chorology, And Ecology, Heinrich Dörfelt Jan 2005

Die Gasteromyceten Der Mongolei Und Ihre Bedeutung Für Die Systematik, Chorologie Und Ökologie) = The Mongolian Gasteromycetes And Their Importance For The Systematics, Chorology, And Ecology, Heinrich Dörfelt

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

More than fifty species of Gasteromycetes were collected in Mongolia from 1970 to 2002. Five new species in the genera Geastrum, Lycoperdon, Gastrosporium, and Colus were described by Pilát (1972), Kreisel (1975), Dörfelt (1981) and Dörfelt & Bumžaa (1986). The importance of Mongolian Gasteromycetes for few taxonomical, chorological or ecological problems is discussed in this paper, especially for the species Battarraea phalloides, Disciseda arida, D. bovista, D. candida, Gastrosporium asiaticum, Geastrum simplex, G. corollinum (G. recolligens), G. deylii, G. floriforme, G. huneckii, G. hungaricum, G. …


Feasibility Of Mapping Benthic Biotopes In The Hudson River, Nicole P. Maher, Robert M. Cerrato Mar 2004

Feasibility Of Mapping Benthic Biotopes In The Hudson River, Nicole P. Maher, Robert M. Cerrato

School of Marine & Atmospheric Sciences Faculty Publications

Successful management of aquatic resources requires comprehensive maps that identify the spatial distribution and extent of potentially vulnerable habitats and their resident biota (e.g., essential fish habitat). We illustrate a technique that describes submerged landscapes not only in terms of geophysical properties, but also in terms of the resident biotic communities. Biological community distribution was highly correlated with the geophysical provinces initially identified by Bell et al. (2000). However, fewer groups of stations (created mainly by combining provinces) explained almost as much of the variation in benthic community structure and was a better description of the major biotopes in this …


Relationships Between Needle Nitrogen Concentration And Photosynthetic Responses Of Douglas-Fir Seedlings To Elevated Co2 And Temperature, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey Jan 2004

Relationships Between Needle Nitrogen Concentration And Photosynthetic Responses Of Douglas-Fir Seedlings To Elevated Co2 And Temperature, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey

Environmental Science and Management Faculty Publications and Presentations

  • Here we examined correlations between needle nitrogen concentration ([N]) and photosynthetic responses of Douglas-fir (Pseudotsuga menziesii) seedlings to growth in elevated temperatures and atmospheric carbon dioxide concentrations ([CO2]).
  • Seedlings were grown in sunlit, climate-controlled chambers at ambient or ambient+3.5° C and ambient or ambient +180 μmol mol-1 CO2 in a full factorial design. Photosynthetic parameters and needle [N] were measured six times over a 21-month period.
  • Needle [N] varied seasonally, and accounted for 30–50% of the variation in photosynthetic parameters. Across measurement periods, elevated temperature increased needle [N] by 26% and light-saturated …


Stomatal Responses Of Douglas-Fir Seedlings To Elevated Carbon Dioxide And Temperature During The Third And Fourth Years Of Exposure, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey Jan 2002

Stomatal Responses Of Douglas-Fir Seedlings To Elevated Carbon Dioxide And Temperature During The Third And Fourth Years Of Exposure, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey

Environmental Science and Management Faculty Publications and Presentations

Two major components of climate change, increasing atmospheric [CO2] and increasing temperature, may substantially alter the effects of water availability to plants through effects on the rate of water loss from leaves. We examined the interactive effects of elevated [CO2] and temperature on seasonal patterns of stomatal conductance (gs), transpiration (E) and instantaneous transpiration efficiency (ITE) in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings. Seedlings were grown in sunlit chambers at either ambient CO2 (AC) or ambient + 180 µmol mol-1 CO2 (EC), and at ambient temperature (AT) or ambient + 3.5° …


Seasonal Patterns Of Photosynthesis In Douglas Fir Seedlings During The Third And Fourth Year Of Exposure To Elevated Co2 And Temperature, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey May 2001

Seasonal Patterns Of Photosynthesis In Douglas Fir Seedlings During The Third And Fourth Year Of Exposure To Elevated Co2 And Temperature, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey

Environmental Science and Management Faculty Publications and Presentations

The interactive effects of elevated atmospheric CO2 and temperature on seasonal patterns of photosynthesis in Douglas fir (Psuedotsuga menziesii (Mirb.) Franco) seedlings were examined. Seedlings were grown in sunlit chambers controlled to track either ambient (~400 p.p.m.) CO2 or ambient +200 p.p.m. CO2, and either ambient temperature or ambient +4 °C. Light-saturated net photosynthetic rates were measured approximately monthly over a 21 month period. Elevated CO2 increased net photosynthetic rates by an average of 21% across temperature treatments during both the 1996 hydrologic year, the third year of exposure, and the 1997 hydrologic year. Elevated …


Internal Temperature Of Douglas-Fir Buds Is Altered At Elevated Temperature, Martha E. Apple, Melissa S. Lucash, David M. Olszyk, David T. Tingey, Donald L. Phillips Feb 1999

Internal Temperature Of Douglas-Fir Buds Is Altered At Elevated Temperature, Martha E. Apple, Melissa S. Lucash, David M. Olszyk, David T. Tingey, Donald L. Phillips

Environmental Science and Management Faculty Publications and Presentations

Pseudotsuga menziesii (Douglas-fir) saplings were grown in sun-lit controlled environment chambers at ambient or elevated (4°C above ambient) temperature. We measured internal temperatures of vegetative buds with thermocouple probes and compared temperatures of normal buds and abnormal buds with loosened, rosetted outer scales in elevated temperature chambers. The abnormal buds had higher and earlier peak daily temperatures than normal buds. Elevated temperature may influence the internal temperature of buds and contribute to the development of abnormal, rosetted buds with loosened outer scales. Abnormal bud development may alter branching patterns and allometry of Douglas-fir trees subjected to climatic change.