Genetics and Genomics Commons^™

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 …

Biodiversity Within Aspen Forests, Paul C. Rogers

Aspen Bibliography

Aspen have long been known for supporting lush vegetation and rich wildlife habitat. These features, alongside brilliant green and gold seasonal coloration, accompany a broadly appreciated aesthetic for aspen forests by the public-at-large. However, in earlier times timber producers in many locales considered aspen to have low value and actively eliminated them. More recent research has pointed out that relative moisture held within aspen communities facilitates a wide array of species – collectively, biodiversity – compared to surrounding vegetation types. Aspen groves in the Intermountain West, for example, are known to be second only to riparian forests is supporting the …

Role Of Wildfire And Topography In Shaping Aspen Regeneration After The Hayman Fire, Co, Usa, Arianna A. B. Porter

Aspen Bibliography

Unusually rapid and widespread mortality in Quaking aspen (Populus tremuloides) has been documented throughout the 21st century primarily as a result of warm, dry weather conditions. Although aspen are not drought-adapted, aspen are well adapted to wildfire. Increases in wildfire severity and extent as a result of climate change may provide opportunities for aspen regeneration, especially at mid- and high-elevation sites. Aspen's sensitivity to drought suggests that regeneration following fire might be constrained to cooler and wetter topographic locations on the landscape which reduce drought stress on vegetation. While aspen mortality is demonstrated to occur at low elevation sites, aspen …

Burn Severity And Fire History In The Northwestern Canadian Boreal Forest: Drivers And Ecological Outcomes, Ellen Whitman

Aspen Bibliography

Wildfire is the dominant stand-renewing disturbance in the northwestern Canadian boreal forest. Fires burn extensive areas in Canada, disturbing an average of 1.96 Mha yr−1, primarily in the boreal zone. Fires generally occur every ~30 – > 200 years in this region, due in part to a lack of fuel that allows young stands to resist reburning. Boreal understory plants and trees are adapted to stand-renewing wildfire through mechanisms such as serotiny, seed banking, and resprouting from roots and rhizomes of top-killed individuals. Such adaptations confer resilience to boreal forests, and post-fire vegetation communities generally resemble the pre-fire ones, following a …

The Role Of Disease & Insects In Aspen Ecology, John C. Guyon Ii

Aspen Bibliography

Aspen is a keystone species in montane forests, and enhances a number of key resource values including wildlife habitat, water resources, and fire behavior. Recently, aspen forests have experienced episodes of dieback and decline across western North America (Worrall et al. 2010, Guyon and Hoffman 2011). A large proportion of the dieback and decline has been linked to drought stress or drought-prone locations (Hanna and Kulakowski 2012). However, insects and diseases are commonly found in declining aspen stands, leading to confusion about the role of insects and diseases in aspen ecology. Additionally, aspen has a reputation for being susceptible to …

Surface Fire To Crown Fire: Fire History In The Taos Valley Watersheds, New Mexico, Usa, Lane B. Johnson, Ellis Q. Margolis

Aspen Bibliography

Tree-ring fire scars, tree ages, historical photographs, and historical surveys indicate that, for centuries, fire played different ecological roles across gradients of elevation, forest, and fire regimes in the Taos Valley Watersheds. Historical fire regimes collapsed across the three watersheds by 1899, leaving all sites without fire for at least 119 years. Historical photographs and quaking aspen (Populus tremuloides Michx.) ages indicate that a high-severity fire historically burned at multiple high-elevation subalpine plots in today’s Village of Taos Ski Valley, with large high-severity patches (>640 ha). Low-severity, frequent (9–29-year median interval) surface fires burned on the south aspects …

Using Publicly Available Genbank Data To Teach Plant Phylogeny In High School Classrooms, Madhav P. Nepal, Ethan J. Andersen

iLEARN Teaching Resources

In this teaching module, students will learn about NCBI GenBank, search for DNA/protein sequences from multiple plant species of a gene that encodes Rubisco enzyme, construct and interpret a phylogenetic tree, and discuss traits that allowed plants to adapt their life on land.

Climate Change, Woodpeckers, And Forests: Current Trends And Future Modeling Needs, Eric S. Walsh, Kerri T. Vierling, Eva Strand, Kristina Bartowitz, Tara W. Hudiburg

Aspen Bibliography

The structure and composition of forest ecosystems are expected to shift with climate‐induced changes in precipitation, temperature, fire, carbon mitigation strategies, and biological disturbance. These factors are likely to have biodiversity implications. However, climate‐driven forest ecosystem models used to predict changes to forest structure and composition are not coupled to models used to predict changes to biodiversity. We proposed integrating woodpecker response (biodiversity indicator) with forest ecosystem models. Woodpeckers are a good indicator species of forest ecosystem dynamics, because they are ecologically constrained by landscape‐scale forest components, such as composition, structure, disturbance regimes, and management activities. In addition, they are …

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 …

Application Of Short Tandem Target Mimic (Sttm) Technique For Functional Analysis Of Micro-Rna396 In Transgenic Poplar Trees, Surattana Boonsai

Dissertations, Master's Theses and Master's Reports

Short Tandem Target Mimic (STTM) is a commonly technique used for functional studies of a number of genes in several plant model systems. However, very little is known about application of STTM technique in tree species. In this study, STTM was applied to knock down microRNA396 (miR396) in transgenic poplar trees for the first time. STTM396 expression resulted in dramatic decrease in miR396 expression levels leading to taller plants with larger leaves and larger leaf cell size. Additionally, an expression analysis of growth regulating factor genes (GRFs) that are members of miR396 target gene family showed up-regulation of GRF07 gene …

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 …

Dependence Of Aspen Stands On A Subsurface Water Subsidy: Implications For Climate Change Impacts, D. M. Love, M. D. Venturas, J. S. Sperry, P. D. Brooks, J. L. Pettit, Y. Wang, W. R. L. Anderegg, X. Tai, D. S. Mackay

Aspen Bibliography

The reliance of 10 Utah (USA) aspen forests on direct infiltration of growing season rain versus an additional subsurface water subsidy was determined from a trait- and process-based model of stomatal control. The model simulated the relationship between water supply to the root zone versus canopy transpiration and assimilation over a growing season. Canopy flux thresholds were identified that distinguished nonstressed, stressed, and dying stands. We found growing season rain and local soil moisture were insufficient for the survival of 5 of 10 stands. Six stands required a substantial subsidy (31–80% of potential seasonal transpiration) to avoid water stress and …

Gene Network Analysis Of Poplar Root Transcriptome In Response To Drought Stress Identifies A Ptajaz3ptarap2.6-Centered Hierarchical Network, Madhumita Dash, Yordan S. Yordanov, Tatyana Georgieva, Hairong Wei, Victor Busov

College of Forest Resources and Environmental Science Publications

Using time-series transcriptomic data from poplar roots undergoing polyethylene glycol (PEG)-induced drought stress, we built a genetic network model of the involved putative molecular responses. We found that the network resembled a hierarchical structure. The highest hierarchical level in this structure is occupied by 9 genes, which we called superhubs because they were primarily connected to 18 hub genes, which are then connected to 2,934 terminal genes. We were only able to regenerate transgenic plants overexpressing two of the superhubs, suggesting that the majority of the superhubs might interfere with the regeneration process and did not allow recovery of transgenic …

Phylogeographic Analyses Of A Widely Distributed Populus Davidiana: Further Evidence For The Existence Of Glacial Refugia Of Cool‐Temperate Deciduous Trees In Northern East Asia, Zhe Hou, Zhaoshan Wang, Zhanyang Ye, Shuhui Du, Shuya Liu, Jianguo Zhang

Aspen Bibliography

Despite several phylogeographic studies had provided evidence to support the existence of glacial refugia of cool‐temperate deciduous trees in northeast China, the species used in these studies were limited by the species ranges, which could not exclude the possibility that northern populations were the colonists from southern refugial populations during the last glacial maximum (LGM). Here, we estimated the nucleotide variation in Populus davidiana, a widespread species distributed in Eurasia. Three groups in northeast, central, and southwest China were constructed according to the simulation results from SAMOVA, composition of chloroplast haplotypes and structure results. We revealed that the northeast …

Aspen Recruitment In The Yellowstone Region Linked To Reduced Herbivory After Large Carnivore Restoration, Luke E. Painter, Robert L. Beschta, Eric J. Larsen, William J. Ripple

Aspen Bibliography

Quaking aspen (Populus tremuloides) recruitment during the 1980s–90s was suppressed by Rocky Mountain elk (Cervus canadensis) herbivory on winter ranges in the Yellowstone region, and saplings (young aspen taller than 2 m) were rare. Following the 1995–96 reintroduction of gray wolves (Canis lupus), browsing decreased and sapling recruitment increased in Yellowstone National Park. We compared aspen data from inside the park to data collected in three winter ranges outside the park. For most areas, the percentage of young aspen browsed annually was 80–100% in 1997–98, decreasing to 30–60% in 2011–15. Sapling recruitment was inversely …

Effects Of Stand Structure, Browsing, And Biophysical Conditions On Regeneration Following Mountain Pine Beetle In Mixed Lodgepole Pine And Aspen Forests Of The Southern Rockies, Kristen A. Pelz, Frederick W. Smith

Aspen Bibliography

Aspen (Populus tremuloides) and lodgepole pine (Pinus contorta var. latifolia) co-occur in the southern Rocky Mountains (USA), where mountain pine beetle (MPB, Dendroctonus ponderosae) has caused extensive lodgepole pine mortality since the late 1990s. Both species excel in post-disturbance high-light environments, but lodgepole pine has generally been thought to establish poorly on undisturbed seedbeds, and aspen suckering may be inhibited by intact aspen overstory. We ask whether lodgepole pine and aspen will regenerate in sufficient quantities to revegetate these forests. We visited a random sample of aspen and lodgepole pine stands across the affected landscape …

Fitness Consequences Of Interspecific Nesting Associations Among Cavity-Nesting Birds, James C. Mouton, Thomas E. Martin

Aspen Bibliography

Interspecific aggregations of prey may provide benefits by mitigating predation risk, but they can also create costs if they increase competition for resources or are more easily detectable by predators. Variation in predation risk and resource availability may influence the occurrence and fitness effects of aggregating in nature. Yet tests of such possibilities are lacking. Cavity-nesting birds provide an interesting test case. They compete aggressively for resources and experience low nest predation rates, which might predict dispersion, but across 19 years of study we found that they commonly aggregate by sharing nest trees. Tree sharing was more common when aspen …

Removal Of Invasive Plants From Pando Exclosure 2018, Marc Coles-Ritchie

Aspen Bibliography

On July 10-11, 2018 volunteers and staff from Great Old Broads for Wilderness and Grand Canyon Trust removed invasive plants from the Pando exclosure, a fenced portion of the Pando Clone aspen forest adjacent to Fish Lake, in Central Utah. This area has been fenced to restore a portion of the Pando Clone that has been lacking recruitment for decades, by protecting young aspen from browsing by deer and cattle. We have been removing invasive species for five years from this exclosure.

The 2018 trip included 10 women and one staffer of Great Old Broads for Wilderness, from the states …

Phytochemical Screening Of Quaking Aspen (Populus Tremuloides) Extracts By Uplc-Qtof-Ms And Evaluation Of Their Antimicrobial Activity, Annabelle St-Pierre, Dorian Blondeau, André Lajeunesse, Julien Bley, Nathalie Bourdeau, Isabel Desgagné-Penix

Aspen Bibliography

The continual emergence of pathogen resistance is a recurring challenge and pushes for the development of antimicrobial compounds. Here, we investigated compounds from quaking aspen trees (Populus tremuloides) as potential antimicrobial agents. Several extractions using different solvents were realized, and corresponding antimicrobial activity was tested against eight microorganisms. Results revealed that polar extraction solvents including water, ethanol and methanol gave the best extraction yields (>15.07%). Minimal inhibition concentration (MIC) and minimal bactericidal/fungicidal concentration (MBC/MFC) demonstrated that water extracts had the best antimicrobial activity by a weak to moderate inhibition of growth of all eight tested microorganisms in addition to …

Rapid Regeneration Offsets Losses From Warming-Induced Tree Mortality In An Aspen-Dominated Broad-Leaved Forest In Northern China, Pengwu Zhao, Chongyang Xu, Mei Zhou, Bo Zhang, Peng Ge, Nan Zeng, Hongyan Liu

Aspen Bibliography

Worldwide tree mortality as induced by climate change presents a challenge to forest managers. To successfully manage vulnerable forests requires the capacity of regeneration to compensate for losses from tree mortality. We observed rapid regeneration and the growth release of young trees after warming-induced mortality in a David aspen-dominated (Populus davidiana) broad-leaved forest in Inner Mongolia, China, as based on individual tree measurements taken in 2012 and 2015 from a 6-ha permanent plot. Warming and drought stress killed large trees 10–15 m tall with a total number of 2881 trees during 2011–2012, and also thinned the upper crowns. …

Large Effect Quantitative Trait Loci For Salicinoid Phenolic Glycosides In Populus: Implications For Gene Discovery, Scott A. Woolbright, Brian J. Rehill, Richard L. Lindroth

Aspen Bibliography

Genomic studies have been used to identify genes underlying many important plant secondary metabolic pathways. However, genes for salicinoid phenolic glycosides (SPGs)—ecologically important compounds with significant commercial, cultural, and medicinal applications—remain largely undescribed. We used a linkage map derived from a full‐sib population of hybrid cottonwoods (Populus spp.) to search for quantitative trait loci (QTL) for the SPGs salicortin and HCH‐salicortin. SSR markers and primer sequences were used to anchor the map to the V3.0 P. trichocarpa genome. We discovered 21 QTL for the two traits, including a major QTL for HCH‐salicortin (R2 = .52) that colocated …

The Impact Of Reconstructed Soils Following Oil Sands Exploitation On Aspen And Its Associated Belowground Microbiome, Franck Stefani, Nathalie Isabel, Marie-Josee Morency

Aspen Bibliography

Oil sands surface mining in the Athabasca region of northern Alberta (Canada) is a significant anthropogenic disturbance that resets boreal forest development and succession to early stages. During surface mining, the vegetation is cleared, the topsoil is salvaged, and the overburden (the layer of sand and clay in between the topsoil and the oil sands) is piled (see Fig. 2 in Audet et al.1 for an explanation of the land-reclamation procedure). After mining is finished, the landforms (composed of overburden and tailings sand) are capped with organic matter-rich soil covers made of either upland-derived forest floor-mineral mix (FFMM) or a …

Hart Prairie Preserve Site Visit To Assess Aspen Health Nature Conservancy, Flagstaff, Az, Amanda Grady

Aspen Bibliography

On June 11, 2018, Amanda Grady, Entomologist, Arizona Zone, Forest Health Protection, performed a site visit to evaluate aspen health on the Nature Conservancy lands at Heart Prairie Preserve (HPP) near Flagstaff. Specifically, the evaluation was to determine whether or not the aspen within exclosures on Fern Mountain have symptoms or signs of Oystershell scale (OSS), an emergent forest pest contributing to aspen decline in northern Arizona.

Effects Of Climate Change On Forest Vegetation In The Northern Rockies Region, Robert E. Keane, Mary Frances Mahalovich

Aspen Bibliography

No abstract provided.

Climate-Induced Gradients Of Populus Sp. Forest Biomass On The Territory Of Eurasia, Usoltev Vladimir Andreevich, Omid Shobairi, Chasovskikh Viktor Petrovich

Aspen Bibliography

On the basis of the compiled database in a number of 413 sample plots with determinations of forest biomass of the genus Populus sp. on the territory of Eurasia from France to southern China and Japan statistically significant transcontinental decreasing of stem, above ground and total biomass as in the direction from northern temperate to subequatorial zonal belt and in the direction from the Atlantic and Pacific coasts to the continentality pole in Siberia is established. Unlike wood story, understory biomass in these directions has not decreased, and increasing. The root: shoot ratio increases in the range between northern temperate …

Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind

Theses and Dissertations

Species of trees inhabit diverse and heterogeneous environments, and often play important ecological roles in such communities. As a result of their vast ecological breadth, trees have become adapted to various environmental pressures. In this dissertation I examine various environmental factors that drive evolutionary dynamics in threePinusspecies in California and Nevada, USA. In chapter two, I assess the role of management influence of thinning, fire, and their interaction on fine-scale gene flow within fire-suppressed populations of Pinus lambertiana, a historically dominant and ecologically important member of mixed-conifer forests of the Sierra Nevada, California. Here, I find evidence …

Dna Barcoding Of Quercus Falcata, Quercus Palustris, Quercus Rubra, And Their Hybrids Using Rbcl, Matk, And Ycf1, Mckinzie Johnson, Tim Trott

Research in Biology

No abstract provided.

Oystershell Scale Impacts And Mitigation Options On The Kaibab And Coconino Nf’S, Amanda M. Grady

Aspen Bibliography

This report documents a site visit to evaluate aspen stands experiencing oystershell scale damage on the Kaibab and Coconino National Forest’s. The site visit was requested by Kaibab NF, foresters including; Josh Giles, Jessi Outzs, Michael Sedgeman, Woody Rokala and Coconino Silviculturist, Mark Nabel. On November 19, 2016, Amanda Grady accompanied the individuals listed above, to evaluate stand conditions within three aspen exclosures. Two were located on the Williams Ranger District, Kaibab NF in the vicinity of Spring Valley. The third exclosure was located on the Flagstaff RD, Coconino NF and accessed from HWY 89-A via the Pump House Wash …

Species Delimitation And Lineage Separation History Of A Species Complex Of Aspens In China, Honglei Zheng, Liqiang Fan, Richard I. Milne, Lei Zhang, Yaling Wang, Kangshan Mao

Aspen Bibliography

Species delimitation in tree species is notoriously challenging due to shared polymorphisms among species. An integrative survey that considers multiple operational criteria is a possible solution, and we aimed to test it in a species complex of aspens in China. Genetic [four chloroplast DNA (cpDNA) fragments and 14 nuclear microsatellite loci (nSSR)] and morphological variations were collected for 76 populations and 53 populations, respectively, covering the major geographic distribution of the Populus davidiana-rotundifoliacomplex. Bayesian clustering, analysis of molecular variance (AMOVA), Principle Coordinate Analysis (PCoA), ecological niche modeling (ENM), and gene flow (migrants per generation), were employed to …

Restoration Of The Iconic Pando Aspen Clone: Emerging Evidence Of Recovery, Paul C. Rogers, Jody A. Gale

Aspen Bibliography

Quaking aspen (Populus tremuloides Michx.) is being stressed across the America West from a variety of sources including drought, herbivory, fire suppression, development, and past management practices. Rich assemblages of plants and animals that utilize aspen forests, as well as economic values of tourism, grazing, hunting, and water conservation, make aspen ecosystems among the most valuable vegetation types in this region. The 43-ha Pando clone near Fish Lake, Utah, is an iconic example of an aspen community undergoing rapid decline due to overstory mortality and chronic recruitment failure. As part of a larger project to restore Pando, we fenced, …