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Full-Text Articles in Life Sciences

Bison Alter The Northern Yellowstone Ecosystem By Breaking Aspen Saplings, Luke E. Painter, Robert L. Beschta, William J. Ripple Aug 2023

Bison Alter The Northern Yellowstone Ecosystem By Breaking Aspen Saplings, Luke E. Painter, Robert L. Beschta, William J. Ripple

Aspen Bibliography

The American bison (Bison bison) is a species that strongly interacts with its environment, yet the effects of this large herbivore on quaking aspen (Populus tremuloides) have received little study. We documented bison breaking the stems of aspen saplings (young aspen > 2 m tall and ≤ 5 cm in diameter at breast height) and examined the extent of this effect in northern Yellowstone National Park (YNP). Low densities of Rocky Mountain elk (Cervus canadensis) after about 2004 created conditions conducive for new aspen recruitment in YNP's northern ungulate winter range (northern range). We sampled …


Less Fuel For The Next Fire? Short-Interval Fire Delays Forest Recovery And Interacting Drivers Amplify Effects, Kristin H. Braziunas, Nathan G. Kiel, Monica G. Turner Mar 2023

Less Fuel For The Next Fire? Short-Interval Fire Delays Forest Recovery And Interacting Drivers Amplify Effects, Kristin H. Braziunas, Nathan G. Kiel, Monica G. Turner

Aspen Bibliography

As 21st-century climate and disturbance dynamics depart from historic baselines, ecosystem resilience is uncertain. Multiple drivers are changing simultaneously, and interactions among drivers could amplify ecosystem vulnerability to change. Subalpine forests in Greater Yellowstone (Northern Rocky Mountains, USA) were historically resilient to infrequent (100–300 year), severe fire. We sampled paired short-interval (<30-year) and long-interval (>125-year) post-fire plots most recently burned between 1988 and 2018 to address two questions: (1) How do short-interval fire, climate, topography, and distance to unburned live forest edge interact to affect post-fire forest regeneration? (2) How do forest biomass and fuels vary following short-interval versus long-interval severe fires? …


Revisiting Trophic Cascades And Aspen Recovery In Northern Yellowstone, Robert L. Beschta, Luke E. Painter, William J. Ripple Mar 2023

Revisiting Trophic Cascades And Aspen Recovery In Northern Yellowstone, Robert L. Beschta, Luke E. Painter, William J. Ripple

Aspen Bibliography

We revisit the nature and extent of trophic cascades and quaking aspen (Populus tremuloides) recovery in the northern range of Yellowstone National Park (YNP), where studies have reported on Rocky Mountain elk (Cervus canadensis) browsing and young aspen heights following the St. John, 1995-96 reintroduction of gray wolves (Canis lupus). A recent study by Brice et al. (2021) expressed concerns about methodologies employed in earlier aspen studies and that results from those studies exaggerated the extent to which a trophic cascade has benefitted aspen, concerns such as: (a) the selection of aspen stands, (b) …


Assessment Of Carbon Productivity Dynamics In Aspen Stands Under Climate Change Based On Forest Inventories In Central Siberia, Andrey Andreevich Vais, Valentina Valerievna Popova, Alina Andreevna Andronova, Viktor Nikolaevich Nemich, Artem Gennadievich Nepovinnykh, Pavel Vladimirovich Mikhaylov Jan 2023

Assessment Of Carbon Productivity Dynamics In Aspen Stands Under Climate Change Based On Forest Inventories In Central Siberia, Andrey Andreevich Vais, Valentina Valerievna Popova, Alina Andreevna Andronova, Viktor Nikolaevich Nemich, Artem Gennadievich Nepovinnykh, Pavel Vladimirovich Mikhaylov

Aspen Bibliography

The aim of the present research was to study the dynamics of growth and conditions of aspen stands under climate change, according to different periods of forest inventory. The study was conducted in modal aspen forests growing in the subtaiga/forest steppe region of Central Siberia. Aspen forests grow intensively at young age, which allows them to realize maximum carbon sequestration potential. The research was based on forest inventory data from 1972, 1982, 2002, and 2021 (the study was conducted on a limited territory). There was a steady increase in temperatures in the growing season from 1982 to 2002. The amount …


Pando's Pulse: Vital Signs Signal Need For Course Correction At World-Renowned Aspen Forest, Paul C. Rogers Sep 2022

Pando's Pulse: Vital Signs Signal Need For Course Correction At World-Renowned Aspen Forest, Paul C. Rogers

Aspen Bibliography

Upland aspen (Populus spp.) forests contribute significantly to biodiversity in their circumboreal role as keystone species. As aspen ecosystems flourish or diminish, myriad dependent species follow suit. The 43-hectare Pando aspen (Populus tremuloides Michx.) clone in Utah, USA, is thought to be the largest living organism on earth, but is faltering due to chronic herbivory. Long-term resilience in aspen communities, including Pando, rests on successful recruitment of vegetative suckers that are nutritiously desirable to browsing ungulates. Here, I evaluate aspen reproduction alongside numerous vital indicators of Pando's status in the first trend assessment of this embattled iconic forest. …


Growing Space Management In Boreal Mixedwood Forests: 22 Year Results, Richard Kabzems, George Harper, Che Elkin Jun 2022

Growing Space Management In Boreal Mixedwood Forests: 22 Year Results, Richard Kabzems, George Harper, Che Elkin

Aspen Bibliography

Boreal mixed forests of trembling aspen (Populus tremuloides) and white spruce (Picea glauca) can provide higher outputs of many ecosystem goods and services, combined with resilience for changing environmental conditions. In this study, we examine the growth of white spruce and aspen over a range of stand compositions created by spot and broadcast treatments of broadleaves using manual and chemical means, aspen spacing, and untreated control. Twenty-two growing seasons postharvest, treatment responses created a range of broadleaf densities and spatial arrangements, reflected in significant differences in heights and diameters of the spruce mixedwood component. At this …


Compensatory Phenolic Induction Dynamics In Aspen After Aphid Infestation, Rajarshi Kumar Gaur, Ilka Nacif De Abreu, Benedicte Riber Albrectsen Jun 2022

Compensatory Phenolic Induction Dynamics In Aspen After Aphid Infestation, Rajarshi Kumar Gaur, Ilka Nacif De Abreu, Benedicte Riber Albrectsen

Aspen Bibliography

Condensed tannins (CTs) are polyphenolics and part of the total phenolic (TP) pool that shape resistance in aspen (Populus tremula). CTs are negatively associated with pathogens, but their resistance properties against herbivores are less understood. CTs shape resistance to pathogens and chewing herbivores and could also shape resistance to aphids. Being chemical pools that are highly variable it can further be questioned whether CT-shaped resistance is better described by constitutive levels, by the induced response potential, or by both. Here, aspen genotypes were propagated and selected to represent a range of inherent abilities to produce and store foliar …


Sampling Bias Exaggerates A Textbook Example Of A Trophic Cascade, Elaine M. Brice, Eric J. Larsen, Daniel R. Macnulty Nov 2021

Sampling Bias Exaggerates A Textbook Example Of A Trophic Cascade, Elaine M. Brice, Eric J. Larsen, Daniel R. Macnulty

Aspen Bibliography

Understanding trophic cascades in terrestrial wildlife communities is a major challenge because these systems are difficult to sample properly. We show how a tradition of non-random sampling has confounded this understanding in a textbook system (Yellowstone National Park) where carnivore [Canis lupus (wolf)] recovery is associated with a trophic cascade involving changes in herbivore [Cervus canadensis (elk)] behaviour and density that promote plant regeneration. Long-term data indicate a practice of sampling only the tallest young plants overestimated regeneration of overstory aspen (Populus tremuloides) by a factor of 4–7 compared to random sampling because it favoured plants taller than the preferred …


Widespread Mortality Of Trembling Aspen (Populus Tremuloides) Throughout Interior Alaskan Boreal Forests Resulting From A Novel Canker Disease, Roger W. Ruess, Loretta M. Winton, Gerard C. Adams Apr 2021

Widespread Mortality Of Trembling Aspen (Populus Tremuloides) Throughout Interior Alaskan Boreal Forests Resulting From A Novel Canker Disease, Roger W. Ruess, Loretta M. Winton, Gerard C. Adams

Aspen Bibliography

Over the past several decades, growth declines and mortality of trembling aspen throughout western Canada and the United States have been linked to drought, often interacting with outbreaks of insects and fungal pathogens, resulting in a “sudden aspen decline” throughout much of aspen’s range. In 2015, we noticed an aggressive fungal canker causing widespread mortality of aspen throughout interior Alaska and initiated a study to quantify potential drivers for the incidence, virulence, and distribution of the disease. Stand-level infection rates among 88 study sites distributed across 6 Alaska ecoregions ranged from < 1 to 69%, with the proportion of trees with canker that were dead averaging 70% across all sites. The disease is most prevalent north of the Alaska Range within the Tanana Kuskokwim ecoregion. Modeling canker probability as a function of ecoregion, stand structure, landscape position, and climate revealed that smaller-diameter trees in older stands with greater aspen basal area have the highest canker incidence and mortality, while younger trees in younger stands appear virtually immune to the disease. Sites with higher summer vapor pressure deficits had significantly higher levels of canker infection and mortality. We believe the combined effects of this novel fungal canker pathogen, drought, and the persistent aspen leaf miner outbreak are triggering feedbacks between carbon starvation and hydraulic failure that are ultimately driving widespread mortality. Warmer early-season temperatures and prolonged late summer drought are leading to larger and more severe wildfires throughout interior Alaska that are favoring a shift from black spruce to forests dominated by Alaska paper birch and aspen. Widespread aspen mortality fostered by this rapidly spreading pathogen has significant implications for successional dynamics, ecosystem function, and feedbacks to disturbance regimes, particularly on sites too dry for Alaska paper birch.


Birds And Bioenergy Within The Americas: A Cross‐National, Social–Ecological Study Of Ecosystem Service Tradeoffs, Jessie L. Knowlton, Kathleen E. Halvorsen, David J. Flaspohler, Christopher R. Webster, Jesse Abrams, Sara M. Almeida, Stefan L. Arriaga‐Weiss, Brad Barnett, Maíra R. Cardoso, Pablo V. Cerqueira, Diana Córdoba, Marcos Persio Dantas‐Santos, Jennifer L. Dunn, Amarella Eastmond, Gina M. Jarvi, Julian A. Licata, Ena Mata‐Zayas, Rodrigo Medeiros, M. Azahara Mesa‐Jurado, Lízbeth Yamily Moo‐Culebro, Cassandra Moseley, Erik Nielsen, Colin Phifer, Erin Pischke, Chelsea Schelly, Theresa Selfa, Chelsea A. Silva, Tatiana Souza, Sam R. Sweitz Mar 2021

Birds And Bioenergy Within The Americas: A Cross‐National, Social–Ecological Study Of Ecosystem Service Tradeoffs, Jessie L. Knowlton, Kathleen E. Halvorsen, David J. Flaspohler, Christopher R. Webster, Jesse Abrams, Sara M. Almeida, Stefan L. Arriaga‐Weiss, Brad Barnett, Maíra R. Cardoso, Pablo V. Cerqueira, Diana Córdoba, Marcos Persio Dantas‐Santos, Jennifer L. Dunn, Amarella Eastmond, Gina M. Jarvi, Julian A. Licata, Ena Mata‐Zayas, Rodrigo Medeiros, M. Azahara Mesa‐Jurado, Lízbeth Yamily Moo‐Culebro, Cassandra Moseley, Erik Nielsen, Colin Phifer, Erin Pischke, Chelsea Schelly, Theresa Selfa, Chelsea A. Silva, Tatiana Souza, Sam R. Sweitz

Michigan Tech Publications

Although renewable energy holds great promise in mitigating climate change, there are socioeconomic and ecological tradeoffs related to each form of renewable energy. Forest‐related bioenergy is especially controversial, because tree plantations often replace land that could be used to grow food crops and can have negative impacts on biodiversity. In this study, we examined public perceptions and ecosystem service tradeoffs between the provisioning services associated with cover types associated with bioenergy crop (feedstock) production and forest habitat‐related supporting services for birds, which themselves provide cultural and regulating services. We combined a social survey‐based assessment of local values and perceptions with …


76-Year Decline And Recovery Of Aspen Mediated By Contrasting Fire Regimes: Long-Unburned, Infrequent And Frequent Mixed-Severity Wildfire, Cerena J. Brewen, John-Pascal Berrill, Martin W. Ritchie, Kevin Boston, Christa M. Dagley, Bobette Jones, Michelle Coppoletta, Coye L. Burnett Feb 2021

76-Year Decline And Recovery Of Aspen Mediated By Contrasting Fire Regimes: Long-Unburned, Infrequent And Frequent Mixed-Severity Wildfire, Cerena J. Brewen, John-Pascal Berrill, Martin W. Ritchie, Kevin Boston, Christa M. Dagley, Bobette Jones, Michelle Coppoletta, Coye L. Burnett

Aspen Bibliography

Quaking aspen (Populus tremuloides) is a valued, minor component on northeastern California landscapes. It provides a wide range of ecosystem services and has been in decline throughout the region for the last century. This decline may be explained partially by the lack of fire on the landscape due to heavier fire suppression, as aspen benefit from fire that eliminates conifer competition and stimulates reproduction through root suckering. However, there is little known about how aspen stand area changes in response to overlapping fire. Our study area in northeastern California on the Lassen, Modoc and Plumas National Forests has …


Aspen Soils Retain More Dissolved Organic Carbon Than Conifer Soils In A Sorption Experiment, Antra Boča, Astrid R. Jacobson, Helga Van Miegroet Dec 2020

Aspen Soils Retain More Dissolved Organic Carbon Than Conifer Soils In A Sorption Experiment, Antra Boča, Astrid R. Jacobson, Helga Van Miegroet

Aspen Bibliography

The effect tree species have on soil organic carbon (SOC) has been hotly debated but, so far, few clear patterns have emerged. One example of a differing tree species effect on SOC are aspen forests in North America, which have been found to have more stable SOC than adjacent conifer forest stands. An important source for the formation of stable organo-mineral complexes in soil is dissolved organic carbon (DOC). DOC concentrations in mineral soil are often higher under the thick O-horizons of conifer forests than under aspen forests, but this does not correspond to more stable mineral SOC. This suggests …


Aspen Next Generation: Conversations From Southern Colorado And Northern New Mexico, Dan Binkley, Bill Romme Jul 2020

Aspen Next Generation: Conversations From Southern Colorado And Northern New Mexico, Dan Binkley, Bill Romme

Aspen Bibliography

Aspen trees and forests are especially important in the Rocky Mountains. Aspens add beauty to landscapes, foster high diversity and productivity of understory plants, provide for the habitat needs of many species of animals, and moderate fire behavior. There is a perception that aspen trees and stands are not regenerating well in southern Colorado and northern New Mexico; cohorts of trees younger than a few decades are scarce, at least in some areas. The next generation of aspen in the southern Rockies will be influenced by land use decisions, including harvesting, fire policy and management, and browsing by livestock and …


Genomic Insights Into Speciation History And Local Adaptation Of An Alpine Aspen In The Qinghai–Tibet Plateau And Adjacent Highlands, Jia-Lang Li, Lin-Ling Zhong, Jing Wang, Tao Ma, Kang-Shan Mao, Lei Zhang Jul 2020

Genomic Insights Into Speciation History And Local Adaptation Of An Alpine Aspen In The Qinghai–Tibet Plateau And Adjacent Highlands, Jia-Lang Li, Lin-Ling Zhong, Jing Wang, Tao Ma, Kang-Shan Mao, Lei Zhang

Aspen Bibliography

Natural selection serves as an important agent to drive and maintain interspecific divergence. Populus rotundifolia Griff. is an alpine aspen species that mainly occurs in the Qinghai–Tibet Plateau (QTP) and adjacent highlands, whereas its sister species, P. davidiana Dode, is distributed across southwest and central to northeast China in much lower altitude regions. In this study, we collected genome resequencing data of 53 P. rotundifolia and 42 P. davidiana individuals across their natural distribution regions. Our population genomic data suggest that the two species are well delimitated in the allopatric regions, but with hybrid zones in their adjacent region in …


Genetic Parameters Of Growth And Adaptive Traits In Aspen (Populus Tremuloides): Implications For Tree Breeding In A Warming World, Chen Ding, Andreas Hamann, Rong-Cai Yang, Jean S. Brouard Mar 2020

Genetic Parameters Of Growth And Adaptive Traits In Aspen (Populus Tremuloides): Implications For Tree Breeding In A Warming World, Chen Ding, Andreas Hamann, Rong-Cai Yang, Jean S. Brouard

Aspen Bibliography

Aspen (Populus tremuloides Michx) is a widespread commercial forest tree of high economic importance in western Canada and has been subject to tree improvement efforts over the past two decades. Such improvement programs rely on accurate estimates of the genetic gain in growth traits and correlated response in adaptive traits that are important for forest health. Here, we estimated genetic parameters in 10 progeny trials containing >30,000 trees with pedigree structures based on a partial factorial mating design that includes 60 half-sibs, 100 full-sib families and 1,400 clonally replicated genotypes. Estimated narrow-sense and broad-sense heritabilities were low for height …


Aspen Growth Response In The Presence Of Inter-Annual Climate Fluctuation And Disturbance In The Lake Tahoe Basin, Keath K. Sakihara Jan 2020

Aspen Growth Response In The Presence Of Inter-Annual Climate Fluctuation And Disturbance In The Lake Tahoe Basin, Keath K. Sakihara

Cal Poly Humboldt theses and projects

In the western US, aspen forests tend to be small and rare, but have great ecological importance. There is much interest and concern over how aspen in the Sierra Nevada Mountains of the western USA will respond to a changing climate and future disturbances. Impacts from climate change create stress on aspen trees that further compound threats to aspen communities. This analysis assessed the radial growth response of aspen under previously recorded climate conditions to better understand how measurable climate variables affect aspen growth. Along with aspen’s growth response to climate, this analysis also assessed the growth response of aspen …


Snowpack Properties Vary In Response To Burn Severity Gradients In Montane Forests, Jordan Maxwell, Samuel B. St. Clair Dec 2019

Snowpack Properties Vary In Response To Burn Severity Gradients In Montane Forests, Jordan Maxwell, Samuel B. St. Clair

Aspen Bibliography

Wildfires are altering ecosystems globally as they change in frequency, size, and severity. As wildfires change vegetation structure, they also alter moisture inputs and energy fluxes which influence snowpack and hydrology. In unburned forests, snow has been shown to accumulate more in small clearings or in stands with low to moderate forest densities. Here we investigate whether peak snowpack varies with burn severity or percent overstory tree mortality post-fire in a mid-latitude, subalpine forest. We found that peak snowpack across the burn severity gradients increased 15% in snow-water equivalence (SWE) and 17% in depth for every 20% increase in overstory …


Everyone In: A Road Map For Science-Based, Collaborative Restoration Of Western Quaking Aspen, Sue Miller Oct 2019

Everyone In: A Road Map For Science-Based, Collaborative Restoration Of Western Quaking Aspen, Sue Miller

Aspen Bibliography

With concern over the health of aspen in the Intermountain West, public and private land managers need better guidance for evaluating aspen condition and selecting and implementing actions that will be effective in restoring aspen health. The Utah Forest Restoration Group collaboratively synthesized a step-by-step approach for aspen restoration that was applicable to western U.S. forests. In a successful case study in shared stewardship, these restoration guidelines were applied to a challenging real-world setting.The Monroe Mountain Aspen Ecosystem Restoration Project, addressed diverse public and private lands needs and interests using an “All Hands, All Lands” strategy. The Monroe Mountain Working …


Historical Population Increases And Related Inciting Factors Of Agrilus Anxius, Agrilus Bilineatus, And Agrilus Granulatus Liragus (Coleoptera: Buprestidae) In The Lake States (Michigan, Minnesota, And Wisconsin), Robert A. Haack, Toby Petrice Sep 2019

Historical Population Increases And Related Inciting Factors Of Agrilus Anxius, Agrilus Bilineatus, And Agrilus Granulatus Liragus (Coleoptera: Buprestidae) In The Lake States (Michigan, Minnesota, And Wisconsin), Robert A. Haack, Toby Petrice

The Great Lakes Entomologist

Three native species of tree-infesting Agrilus have regularly reached outbreak levels in the Lake States (Michigan, Minnesota, and Wisconsin), including A. anxius Gory (bronze birch borer), A. bilineatus (Weber) (twolined chestnut borer), and A. granulatus liragus Barter & Brown (bronze poplar borer). The main host trees for these Agrilus are species of Betula for A. anxius, Castanea and Quercus for A. bilineatus, and Populus for A. granulatus liragus. Based on 197 annual forest health reports for Michigan (1950–2017, 66 years), Minnesota (1950–2017, 64 years), and Wisconsin (1951–2017, 67 years), A. bilineatus was the most often reported Agrilus …


Pleasantview Hills Aspen Stand Diversity Project: Environmental Assessment, Pocatello Field Office Sep 2019

Pleasantview Hills Aspen Stand Diversity Project: Environmental Assessment, Pocatello Field Office

Aspen Bibliography

The Bureau of Land Management (BLM) Pocatello Field Office (PFO) has prepared this Environmental Assessment (EA) to analyze the environmental impacts of implementing treatments on aspen stands in the Pleasantview Hills area. This EA discloses the direct, indirect, and cumulative environmental effects that would result from implementation of this proposal as required by the National Environmental Policy Act (NEPA) of 1969. This EA will determine whether to prepare an Environmental Impact Statement (EIS) or a Finding of No Significant Impact (FONSI) based on environmental impact context and intensity, thereby informing agency decision making. Guidance for EA organization is determined by …


Impacts Of Climate And Insect Herbivory On Productivity And Physiology Of Trembling Aspen (Populus Tremuloides) In Alaskan Boreal Forests, Melissa A. Boyd, Logan T. Berner, Patricia Doak, Scott J. Goetz, Brendan M. Rogers, Diane Wagner, Xanthe J. Walker, Michelle C. Mack Aug 2019

Impacts Of Climate And Insect Herbivory On Productivity And Physiology Of Trembling Aspen (Populus Tremuloides) In Alaskan Boreal Forests, Melissa A. Boyd, Logan T. Berner, Patricia Doak, Scott J. Goetz, Brendan M. Rogers, Diane Wagner, Xanthe J. Walker, Michelle C. Mack

Aspen Bibliography

Climate change is impacting forested ecosystems worldwide, particularly in the Northern Hemisphere where warming has increased at a faster rate than the rest of the globe. As climate warms, trembling aspen (Populus tremuloides) is expected to become more successful in northern boreal forests because of its current presence in drier areas of North America. However, large-scale productivity decline of aspen has recently been documented throughout the United States and Canada as a result of drought and insect outbreaks. We used tree ring measurements (basal area increment (BAI) and stable carbon isotopes (δ 13C)) and remote sensing indices …


Beaver And Aspen: Synergy Among Keystone Species, Stephen N. Bennett, Nicolaas Bouwes, Paul C. Rogers May 2019

Beaver And Aspen: Synergy Among Keystone Species, Stephen N. Bennett, Nicolaas Bouwes, Paul C. Rogers

Aspen Bibliography

In the West, climate change is likely to increase the frequency, intensity, and duration of drought. Restoration of soils and water storage capacity can help create resilient uplands and riverscapes (i.e., streams and the valley bottoms). Over the past two centuries, common land uses, the removal of beaver and wood, straightening of streams, and damage to riparian areas have created simplified, structurally starved, riverscapes. Degraded streams are very efficient at transporting water, sediment, and nutrients downstream. Aspen forests are also biological hotspots that have been degraded by past land uses such as overbrowsing ungulates, land clearing, fire suppression, and outright …


Predatory Hymenopteran Assemblages In Boreal Alaska: Associations With Forest Composition And Post-Fire Succession, Alexandria Wenninger, Teresa Hollingsworth, Diane Wagner Jan 2019

Predatory Hymenopteran Assemblages In Boreal Alaska: Associations With Forest Composition And Post-Fire Succession, Alexandria Wenninger, Teresa Hollingsworth, Diane Wagner

Aspen Bibliography

Changes to the fire regime in boreal Alaska are shifting the ratio of coniferous to deciduous dominance on the landscape. The increase in aspen and birch may have important effects on predatory hymenopteran assemblages by providing a source of extrafloral nectar and increasing prey availability. Furthermore, fire-induced changes in successional age alter habitat structure and microclimate in ways that may favor ants. This study is the first to characterize the influence of fire-related vegetation changes on boreal predatory hymenopteran assemblages. We compare the abundance, species richness, and composition of predatory hymenopteran assemblages among forests at different stages of succession and …


The New Natural Distribution Area Of Aspen (Populus Tremula L.) Marginal Populations In Pasinler In The Erzurum Province, Turkey, And Its Stand Characteristics, Halil Bariş Özel, Sezgin Ayan, Serdar Erpay, Bojan Simovski Dec 2018

The New Natural Distribution Area Of Aspen (Populus Tremula L.) Marginal Populations In Pasinler In The Erzurum Province, Turkey, And Its Stand Characteristics, Halil Bariş Özel, Sezgin Ayan, Serdar Erpay, Bojan Simovski

Aspen Bibliography

Background and Purpose: Genetic diversity is the basis for adaptation and survival of tree species under changing environmental conditions, representing the key issue of stability and productivity of forest ecosystems. This paper studies the marginal population characteristics and stand dynamics of aspen tree (Populus tremula L.) in natural, pure and mixed forest stands with Scots pine (Pinus sylvestris L.). These populations were observed on founding sites between Timarli Valley and Timan Plateau located in Pasinler in the Erzurum Province in Turkey.
Materials and Methods: Three replicated sample sites were established according to a randomised block design …


Effect Of Foliage And Root Carbon Quantity, Quality, And Fluxes On Soil Organic Carbon Stabilization In Montane Aspen And Conifer Stands In Utah, Antra Boča May 2017

Effect Of Foliage And Root Carbon Quantity, Quality, And Fluxes On Soil Organic Carbon Stabilization In Montane Aspen And Conifer Stands In Utah, Antra Boča

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil organic carbon (SOC) positively affects many soil properties (e.g., fertility and water holding capacity), and the amount of carbon (C) in soil exceeds the amount in the atmosphere by about three times. Forest soils store as much C as is found in trees. Tree species differ in their effect on SOC pools. Quaking aspen forests in the Western US often store more stable SOC in the mineral soil than nearby conifers. During the last decades a decline in aspen cover, often followed by conifer encroachment, has been documented. A shift from aspen to conifer overstories may negatively affect the …


Overstory Tree Mortality In The Ponderosa Pine And Spruce-Fir Ecosystems, Following A Drought In Northern New Mexico, Brian P. Oswald, Sean Dugan, Randy Balice, Daniel Unger Jan 2016

Overstory Tree Mortality In The Ponderosa Pine And Spruce-Fir Ecosystems, Following A Drought In Northern New Mexico, Brian P. Oswald, Sean Dugan, Randy Balice, Daniel Unger

Faculty Publications

Drought-caused tree dieback is an issue around the world as climates change and many areas become dryer and hotter. A drought from 1998-2004 resulted in a significant tree dieback event in many of the wooded areas in portions of the Jemez Mountains and the adjacent Pajarito Plateau in northern New Mexico. The objectives of this study were to evaluate and quantify the differences in tree mortality before and after a recent drought in the ponderosa pine and spruce-fir ecosystems, and to assess the effect of mechanical thinning on ponderosa pine mortality. Significant increases in mortality were observed in the unthinned …


Assessing Site Availability Of Aspen And Northern Hardwoods For Potential Feedstock Development In Michigan: A Case Study, Sara Alian, Ann Maclean May 2015

Assessing Site Availability Of Aspen And Northern Hardwoods For Potential Feedstock Development In Michigan: A Case Study, Sara Alian, Ann Maclean

Michigan Tech Publications

The importance of wood and wood byproducts as biomass feedstocks is of increasing interest as a source of ethanol and electricity. Second generation woody feedstock sources in Michigan, e.g., hybrid poplar and hybrid willow (Populus spp.), and native forests, particularly aspen and northern hardwoods, are a potential source of woody biomass for these uses. This study provides a geographic information system (GIS) framework for assessing the current spatial extent of aspen and northern hardwoods) and their proximity to roads. Additionally, the potential for expanding the area of these feedstock sources based on pre-European settlement vegetation cover is assessed. Utilizing GIS …


Length Accuracy Of Logs From Birch And Aspen Harvested In Thinning Operations, Mariusz Bembenek, Piotr S. Mederski, Zbigniew Karaszewski, Agnieszka Lacka, Witold Grzywinski, Andrzej Wegiel, Dieter F. Giefing, Jorn Erler Jan 2015

Length Accuracy Of Logs From Birch And Aspen Harvested In Thinning Operations, Mariusz Bembenek, Piotr S. Mederski, Zbigniew Karaszewski, Agnieszka Lacka, Witold Grzywinski, Andrzej Wegiel, Dieter F. Giefing, Jorn Erler

Turkish Journal of Agriculture and Forestry

No abstract provided.


Assessing Alternative Methods For Monitoring Populus Tremuloides Following Restoration Treatments, Michael Fowler Jan 2014

Assessing Alternative Methods For Monitoring Populus Tremuloides Following Restoration Treatments, Michael Fowler

Graduate Student Theses, Dissertations, & Professional Papers

A variety of alternative sampling methods, commonly known as “Distance Methods”, were tested to determine if they could be a better choice for monitoring Populus tremuloides (quaking aspen) regeneration following aspen restoration treatments. These methods were evaluated based on their ability to accurately and efficiently estimate three common aspen stand characteristics used to gauge aspen restoration treatment effectiveness: aspen regeneration density, browse pressure, and height class distribution. Distance Method accuracy and efficiency were compared to a standard fixed-radius plot sampling method in four treated aspen stands in western Wyoming. None of the Distance Methods fulfilled all of the requirements, which …


Assessment Of Aspen And Northern Hardwoods Extent In Thirty Three Counties Of Upper/Lower Michigan, Sara Alian Jan 2013

Assessment Of Aspen And Northern Hardwoods Extent In Thirty Three Counties Of Upper/Lower Michigan, Sara Alian

Dissertations, Master's Theses and Master's Reports - Open

The importance of the United States' wood and wood byproducts as biomass feedstocks is increasing as the concern about security and sustainability of global energy production continues to rise. Thus, second generation woody feedstock sources in Michigan, e.g., hybrid poplar and hybrid willow (Populus spp.), are viewed as a potential source of biomass for the proposed biofuel ethanol production plant in Kinross, MI. It is important to gain an understanding of the spatial distribution of current feedstock sources, harvesting accessibility via the transportation infrastructure and land ownerships in order to ensure long-term feedstock extent. This research provides insights …