Life Sciences Commons^™

Regeneration Strategies And Forest Resilience To Changing Fire Regimes: Insights From A Goldilocks Model, Tanjona Ramiadantsoa, Zak Ratajczak, Monica G. Turner

Aspen Bibliography

Disturbances are ubiquitous in ecological systems, and species have evolved a range of strategies to resist or rebound following disturbance. Understanding how the presence and complementarity of regeneration traits will affect community responses to disturbance is increasingly urgent as disturbance regimes shift beyond their historical ranges of variability. We define "disturbance niche" as a species' fitness across a range of disturbance sizes and frequencies that can reflect the fundamental or realized niche, that is, whether the species occurs alone or with other species. We developed a model of intermediate complexity (i.e., a Goldilocks model) to infer the disturbance niche. We …

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. …

Hidden Mechanisms Of Climate Impacts In Western Forests: Integrating Theory And Observation For Climate Adaptation, Sara J. Germain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fire, insects, and disease are necessary components of forest ecosystems. Yet, climate change is intensifying these tree stressors and creating new interactions that threaten forest survival. This dissertation combined field observations with statistical predictions of changing disturbances in western forests to identify 1) how conventional models may underestimate future forest loss, and 2) how positive relationships between trees may be exploited by managers to prevent forest loss.

In Chapter II, I tested whether increasingly extreme weather with climate change increases Pacific yew extinction risk. I found that conventional modeling methods underestimated local extinction risk because trees were adapted to a …

Detection Of European Aspen (Populus Tremula L.) Based On An Unmanned Aerial Vehicle Approach In Boreal Forests, Anton Kuzmin, Lauri Korhonen, Sonja Kivinen, Pekka Hurskainen, Pasi Korpelainen, Topi Tanhuanpää, Matti Maltamo, Petteri Vihervaara, Timo Kumpula

Aspen Bibliography

European aspen (Populus tremula L.) is a keystone species for biodiversity of boreal forests. Large-diameter aspens maintain the diversity of hundreds of species, many of which are threatened in Fennoscandia. Due to a low economic value and relatively sparse and scattered occurrence of aspen in boreal forests, there is a lack of information of the spatial and temporal distribution of aspen, which hampers efficient planning and implementation of sustainable forest management practices and conservation efforts. Our objective was to assess identification of European aspen at the individual tree level in a southern boreal forest using high-resolution photogrammetric point cloud …

General Destabilizing Effects Of Eutrophication On Grassland Productivity At Multiple Spatial Scales, Yann Hautier, Pengfei Zhang, Michel Loreau, Kevin R. Wilcox, Eric W. Seabloom, Elizabeth T. Borer, Jarrett E.K. Byrnes, Sally E. Koerner, Kimberly J. Komatsu, Jonathan S. Lefcheck, Andy Hector, Peter B. Adler, Juan Alberti, Carlos A. Arnillas, Jonathan D. Bakker, Lars A. Brudvig, Miguel N. Bugalho, Marc Cadotte, Maria C. Caldeira, Oliver Carroll, Mick Crawley, Scott L. Collins, Pedro Daleo, Laura E. Dee, Nico Eisenhauer, Anu Eskelinen, Philip A. Fay, Benjamin Gilbert, Amandine Hansar, Forest Isbell, Johannes M.H. Knops, Andrew S. Macdougall, Rebecca L. Mcculley, Joslin L. Moore, John W. Morgan, Akira S. Mori, Pablo L. Peri, Edwin T. Pos, Sally A. Power, Jodi N. Price, Peter B. Reich, Anita C. Risch, Christiane Roscher, Mahesh Sankaran, Martin Schütz, Melinda Smith, Carly Stevens, Pedro M. Tognetti, Risto Virtanen, Glenda M. Wardle, Peter A. Wilfahrt, Shaopeng Wang

Wildland Resources Faculty Publications

Eutrophication is a widespread environmental change that usually reduces the stabilizing effect of plant diversity on productivity in local communities. Whether this effect is scale dependent remains to be elucidated. Here, we determine the relationship between plant diversity and temporal stability of productivity for 243 plant communities from 42 grasslands across the globe and quantify the effect of chronic fertilization on these relationships. Unfertilized local communities with more plant species exhibit greater asynchronous dynamics among species in response to natural environmental fluctuations, resulting in greater local stability (alpha stability). Moreover, neighborhood communities that have greater spatial variation in plant species …

Past Management Spurs Differential Plant Communities Within A Giant Single-Clone Aspen Forest, Paul C. Rogers, Jan ŠEbesta

Ecology Center Publications

Sustainable aspen ecosystems hold great promise for global biodiversity conservation. These forests harbor relatively high species diversity, yet are threatened by fire suppression, land development, timber-focused management, extended droughts, and chronic herbivory. “Pando” is a high-profile quaking aspen (Populus tremuloides) forest in Utah, USA which is putatively the ‘largest living organism on earth.’ Pando comprises an estimated 47,000 genetically identical stems, but is threatened by human impacts. Our interest in the present study is whether changes to the giant organism were affecting understorey vegetation and whether discrete zones are displaying divergent community compositions. For instance, recent research has demonstrated strong …

A Global View Of Aspen: Conservation Science For Widespread Keystone Systems, Paul C. Rogers, Bradley D. Pinno, Jan Šebesta, Benedicte R. Albrectsen, Guoqing Li, Natalya Ivanova, Dominik Kulakowski, Antonín Kusbach, Timo Kuuluvainen, Simon M. Landhäusser, Hongyan Liu, Tor Myking, Pertti Pulkkinen, Zhongming Wen

Ecology Center Publications

Across the northern hemisphere, six species of aspen (Populus spp.) play a disproportionately important role in promoting biodiversity, sequestering carbon, limiting forest disturbances, and providing other ecosystem services. In many regions, aspen can maintain canopy dominance for decades to centuries as the sole major broadleaf trees in forested landscapes otherwise dominated by conifers. Aspen ecosystems are valued for many reasons, but here we highlight their potential as key contributors to regional and global biodiversity. We begin with an overview of the aspens’ ecological and economic roles. We then present a systematic literature analysis to assess topics of aspen …

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 …

Weighting Effective Number Of Species Measures By Abundance Weakens Detection Of Diversity Responses, Yong Cao, Charles P. Hawkins

Ecology Center Publications

1. The effective number of species (ENS) has been proposed as a robust measure of species diversity that overcomes several limitations in terms of both diversity indices and species richness (SR). However, it is not yet clear if ENS improves interpretation and comparison of biodiversity monitoring data, and ultimately resource management decisions.

2. We used simulations of five stream macroinvertebrate assemblages and spatially extensive field data of stream fishes and mussels to show (a) how different ENS formulations respond to stress and (b) how diversity–environment relationships change with values of q, which weight ENS measures by species abundances.

3. Values …

Effectiveness Of Snap And A24-Automated Traps And Broadcast Anticoagulant Bait In Suppressing Commensal Rodents In Hawaii, Aaron B. Shiels, Tyler Bogardus, Jobriath Rohrer, Kapua Kawelo

Human–Wildlife Interactions

Commensal rodents (invasive rats, Rattus spp.; house mice, Mus musculus) are well established globally. They threaten human health by disease transfer and impact economies by causing agricultural damage. On island landscapes, they are frequent predators of native species and affect biodiversity. To provide managers with better information regarding methods to suppress commensal rodent populations in remote island forests, in 2016 we evaluated the effectiveness of continuous rat trapping using snap-traps, Goodnature^®A24 self-resetting rat traps, and a 1-time (2-application) hand-broadcast of anticoagulant rodenticide bait pellets (Diphacinone-50) applied at 13.8 kg/ha per application in a 5-ha forest on Oahu, …

Multiple Facets Of Biodiversity Drive The Diversity-Stability Relationship, Dylan Craven, Nico Eisenhauer, William D. Pearse, Yann Hautier, Christiane Roscher, Forest Isbell, Michael Bahn, Carl Beierkuhnlein, Gerhard Bönisch, Nina Buchmann, Chaeho Byun, Jane A. Catford, Bruno E.L. Cerabolini, J. Hans C. Cornelissen, Joseph M. Craine, Enrica De Luca, Anne Ebeling, John N. Griffin, Andy Hector, Jes Hines, Anke Jentsch, Jens Kattge, Jürgen Kreyling, Vojtech Lanta, Nathan Lemoine, Sebastian T. Meyer, Vanessa Minden, Vladimir Onipchenko, H. Wayne Polley, Peter B. Reich, Jasper Van Ruijven, Brandon Schamp, Melinda D. Smith, Nadejda A. Soudzilovskaia, David Tilman, Alexandra Weigelt, Brian Wilsey, Peter Manning

Biology Faculty Publications

A significant body of evidence has demonstrated that biodiversity stabilizes ecosystem functioning over time in grassland ecosystems. However, the relative importance of different facets of biodiversity underlying the diversity–stability relationship remains unclear. Here we used data from 39 biodiversity experiments and structural equation modeling to investigate the roles of species richness, phylogenetic diversity, and both the diversity and community-weighted mean of functional traits representing the ‘fast–slow’ leaf economics spectrum in driving the diversity–stability relationship. We found that high species richness and phylogenetic diversity stabilize biomass production via enhanced asynchrony. Contrary to our hypothesis, low phylogenetic diversity also enhances ecosystem stability …

Competition And Coexistence In Plant Communities: Intraspecific Competition Is Stronger Than Interspecific Competition, Peter B. Adler, Danielle Smull, Karen H. Beard, Ryan T. Choi, Tucker J. Furniss, Andrew Kulmatiski, Joan M. Meiners, Andrew T. Tredennick, Kari E. Veblen

Ecology Center Publications

Theory predicts that intraspecific competition should be stronger than interspecific competition for any pair of stably coexisting species, yet previous literature reviews found little support for this pattern. We screened over 5400 publications and identified 39 studies that quantified phenomenological intraspecific and interspecific interactions in terrestrial plant communities. Of the 67% of species pairs in which both intra‐ and interspecific effects were negative (competitive), intraspecific competition was, on average, four to five‐fold stronger than interspecific competition. Of the remaining pairs, 93% featured intraspecific competition and interspecific facilitation, a situation that stabilises coexistence. The difference between intra‐ and interspecific effects tended …

Lichen Monitoring Delineates Biodiversity On A Great Barrier Reef Coral Cay, Paul C. Rogers, Roderick W. Rogers, Anne Hedrich, Patrick T. Moss

Wildland Resources Faculty Publications

Coral islands around the world are threatened by changing climates. Rising seas, drought, and increased tropical storms are already impacting island ecosystems. We aim to better understand lichen community ecology of coral island forests. We used an epiphytic lichen community survey to gauge Pisonia (Pisonia grandis R.BR.), which dominates forest conditions on Heron Island, Australia. Nine survey plots were sampled for lichen species presence and abundance, all tree diameters and species, GPS location, distance to forest-beach edge, and dominant forest type. Results found only six unique lichens and two lichen associates. A Multi-Response Permutation Procedures (MRPP) test found statistically distinct …

Herbivory Strains Resilience In Drought-Prone Aspen Landscapes Of The Western United States, Paul C. Rogers

Aspen Bibliography

Aims: Aspen forests around the northern hemisphere provide rich biodiversity compared to surrounding vegetation types. In both North America and Europe, however, aspen are threatened by a variety of human impacts: clear-felling, land development, water diversions, fire suppression, and both wild and domestic ungulate herbivory. We conducted a landscape assessment of quaking aspen (Populus tremuloides) for the purpose of identifying key components of resilience. Specifically, we strove to test novel measures linking plant-animal interactions, compare crucial functional differences in aspen types, and make appropriate restorative recommendations based on the outcome of these assessments. Location: The Book Cliffs region of eastern …

Ecological Effects Of Genotypic Diversity On Community And Ecosystem Function, Megan K. Kanaga

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Genotypic diversity within populations can have important evolutionary consequences, but the ecological effects of intraspecific genetic variation on community and ecosystem function have only been studied in a few systems. I present the results of a three-year study designed to address the ecological impacts of genotypic diversity in quaking aspen (Populus tremuloides Michx.), using aspen genotypes planted across genotypic diversity levels (monoculture and mixture) and watering treatment levels (well-watered and water-limited). First, I demonstrated that significant variation exists among genotypes for a wide range of growth, morphological and physiological traits, and quantified high heritability and coefficient of genetic variation …

Effects Of Range Size On Species–Area Relationships, Andrew P. Allen, Ethan P. White

Biology Faculty Publications

It has been known for some time that the slope of the species–area relationship increases asymptotically at broad spatial scales when richness is plotted against area on logarithmic axes. At continental to global scales, species–area relationships are determined to a large extent by the abundance and size distribution of species ranges. Here we present an analytical model that explicitly quantifies the effects of range size on species–area relationships. The model shows how range size and plot area interact to control the form of species–area relationships at broad spatial scales. It also demonstrates how changes in spatial scale affect biodiversity patterns …

Temporal Hierarchies Of Variation And The Maintenance Of Diversity, Peter Chesson, Nancy Huntly

Nancy Huntly

No abstract provided.