Ecology and Evolutionary Biology Commons^™

Mixing Trembling Aspen And White Spruce Increases The Understory Vegetation Cover And Improves Soil Properties But Effects Vary With Broadleaf Density, Mostarin Ara, Bradley D. Pinno, Philip G. Comeau

Aspen Bibliography

Despite the importance of species mixtures to ecosystem-based forest management, density effect of broadleaf trees in the mixture on understory vegetation and soil properties are poorly understood. In this study, we examine the effects of trembling aspen [aspen] (Populus tremuloides Michx.) -white spruce [ spruce] (Picea glauca (Moench) Vos) mixtures that vary in the proportion of aspen on understory vegetation cover, soil nutrient supply rates, and soil properties. Data were collected from an established study located in Alberta, Canada at age 20 and included the following treatments: 1. Natural regeneration of pure aspen; 2. Retaining only …

Geographic Distribution: Smilisca Baudinii (Mexican Treefrog). Usa: Florida: Escambia Co., Louis A. Somma, Justin K. Anto, Jakira A. Davis

Papers in Herpetology

Geographic distribution note for Smilisca baudinii, the Mexican treefrog, from Escambia County, Florida, United States.

Aspen As Firebreaks At The Development Fringe, Kevin Krasnow, Paul C. Rogers

Aspen Bibliography

Quaking aspen (Populus tremuloides) forests are widely known and prized for their numerous values—biodiversity, habitat, forage, recreation, aesthetics, and others—including as a deterrent to wildfire. This reputation for stopping or slowing flames is explored here, alongside measures that may be taken to facilitate thriving aspen communities near human developments. It is clear that science supporting the premise of aspen as an effective firebreak is far from complete. Yet, how can we benefit from what we do know on this topic to increase the probability of preventing structural fire damage, while also encouraging the valued characteristics of aspen ecosystems?

Climate Considerations For Quaking Aspen Conservation, Douglas Shinneman, Susan Mcilroy, Paul C. Rogers

Aspen Bibliography

Human-caused climate change alters ecosystem processes ranging from local to global scales. As a consequence of climate change we should expect increased rates and intensities of disturbance events. Though we are only beginning to understand what those impacts might be to aspen forests and their diverse plant and animal assemblages, recent science suggests there may be unavoidable effects. In the face of anticipated climate-ecosystem challenges, contemporary managers are searching for guidance on preserving aspen resilience. We suggest crafting strategic yet cautious approaches to minimize effects and facilitate broad resilience. For instance, monitoring conditions in and near aspen forests will help …

Agroecology And Soil Stewardship: Values And Techniques Of Smallholder Farmers In Bernalillo County, Stephanie Olivas

Geography ETDs

Agrarian movements around the world use agroecology to build sovereignty and steward dynamic ecosystems. Research has shown that agroecological farmers steward more resilient crops, more resilient soil biomes, and greater biodiversity than conventional agriculture. GIS and remote sensing offer many tools to detect the impacts of these farmers on the environment, but it is less clear how such technologies fit into agroecological goals. This study asks: what values, experiences and knowledge do smallholder producers in Bernalillo County embody in their soil stewardship practices? Also, what experience or knowledge do smallholder producers in Bernalillo County have about remote sensing, and would …

Greening The Edge: Investigating Riparian Buffer Restorations In A Pastoral Setting And Their Effects On Soil Carbon And Microbial Community Composition., Seth Mccullough

Masters Theses, 2020-current

Riparian buffer restoration represents a critical strategy for enhancing ecosystem health and resilience in agricultural landscapes. This study investigates the effects of riparian buffer restoration on soil properties, microbial communities, and carbon dynamics in Rockingham County, VA. Through a comprehensive field study, we assessed the physicochemical properties of soil, microbial biomass, community composition, and soil carbon storage in restored and unrestored riparian buffers. Our findings reveal significant improvements in soil physical properties in restored buffers, including increased soil moisture (p < 0.05) and decreased bulk density (p < 0.01), indicating enhanced soil structure and water retention capacity. While no significant differences were detected in soil pH or cation exchange capacity, restored buffers exhibited higher soil carbon stocks (p < 0.05) and carbon-to-nitrogen ratios, suggesting potential differences in nutrient cycling processes and organic matter decomposition rates. Moreover, restored buffers showed increased microbial biomass (p < 0.01), potentially driven by improved habitat conditions and shifts towards a fungal-dominated microbial community.

Although no significant differences were found in overall microbial community composition between restored and unrestored sites, specific shifts in bacterial …

Ancient Wisdom, Modern Prosperity: Harnessing Traditional Ecological Knowledge To Revitalize Australia's Economy, Environment, And Human Wellbeing, Annabelle L. Baulch

Student Theses 2015-Present

This paper explores the traditional knowledge of Australia’s Indigenous people and how it can improve Australia's environment, health, and economic prosperity to shape a more sustainable future. Indigenous Australians managed the land for thousands of years; however, being forced off the land following European colonization resulted in terrible cultural, social, and environmental disruption for Aboriginal Australians and made conservation efforts difficult. Wildfires, imported species, mining, and agriculture is steadily destroying the Australian ecosystem, contributing to climate change, species extinction, and gaps in our cultural and ancestral knowledge. Chapter One overviews Australia's environmental issues; it uses quantitative data to explore the …

Assessing Health Implications Of Monarch Butterfly Populations And Behaviors, Kira Goldman, Kelsey E. Fisher Dr.

Honors Scholar Theses

Pollinator populations have seen massive declines over the past decade due to anthropogenic activity and climate change posing serious threats to the health of humans and ecosystems (Ulyshen & Horn, 2023). As agents responsible for the production of about 35% of micronutrient rich food crops necessary for adequate nutrition to lead healthful lives and prevent nutrition associated diseases, pollinator decline is a public health concern (Aizen et al., 2009). Monarch butterflies (Danaus plexippus) serve as bio indicators for the health of pollinator populations because of their analogous habitat and food resources shared with many other pollinator species, including bees and …

Mapping Quaking Aspen Using Seasonal Sentinel-1 And Sentinel-2 Composite Imagery Across The Southern Rockies, Usa, Maxwell Cook, Teresa Chapman, Sarah Hart, Asha Paudel, Jennifer Balch

Aspen Bibliography

Quaking aspen is an important deciduous tree species across interior western U.S. forests. Existing maps of aspen distribution are based on Landsat imagery and often miss small stands ( < 0.09 ha or 30 m²), which rapidly regrow when managed or following disturbance. In this study, we present methods for deriving a new regional map of aspen forests using one year of Sentinel-1 (S1) and Sentinel-2 (S2) imagery in Google Earth Engine. Using observed annual phenology of aspen across the Southern Rockies and leveraging the frequent temporal resolution of S1 and S2, ecologically relevant seasonal imagery composites were developed. We derived spectral indices and …

Sustainability And Drivers Of Populus Tremuloides Regeneration And Recruitment Near The Southwestern Edge Of Its Range, Connor D. Crouch, Nicholas P. Wilhelmi, Paul C. Rogers, Margaret M. Moore, Kristen M. Waring

Aspen Bibliography

Quaking aspen (Populus tremuloides Michx.) ecosystems are highly valued in the southwestern United States because of the ecological, economic, and aesthetic benefits they provide. Aspen has experienced extensive mortality in recent decades, and there is evidence that many areas in Arizona, United States lack adequate recruitment to replace dying overstory trees. Maintaining sustainable levels of regeneration and recruitment (i.e. juveniles) is critical for promoting aspen ecosystem resilience and adaptive capacity, but questions remain about which factors currently limit juvenile aspen and which strategies are appropriate for managing aspen in an increasingly uncertain future. To fill these critical knowledge gaps, …

Effects Of Fungal Biopesticide Doses On Mortality In Bumble Bees, Colton Burris

Undergraduate Research Symposium

Agricultural practices often include the use of pesticides to produce meaningful crop yields. While the pesticide may be used to target “pest” insects (e.g. thrips, aphids, whiteflies), it can also have negative effects on important pollinating insects such as bees. Neonicotinoid pesticides have been found responsible for widespread decline in bee biodiversity, and were even banned in Europe (Sgolastra et al. 2020) . Beauveria bassiana, sold as Botanigard, on the other hand, is a fungal biopesticide that is marketed to be a safer alternative for bees, and has been found to have other possibly harmful effects to the inner …

Where Have All The Flowers Gone? A Call For Federal Leadership In Deer Management In The United States, Bernd Blossey, Darragh Hare, Donald M. Waller

Aspen Bibliography

Forests in the United States continue to lose biodiversity and many fail to regenerate due to high deer (family Cervidae) abundance. Declines in biodiversity and overall ecosystem health due to high deer populations increases prevalence of wildlife and human diseases associated with increasing tick abundances and decreases forest resilience and the ability to deliver benefits provided by healthy ecosystems. In the eastern and midwestern United States, white-tailed deer (Odocoileus virginianus) are the main stressor, while in the western U.S. elk (Cervus elaphus) and black-tailed and mule deer (Odocoileus hemionus) can become equally problematic. Federal …

Avian Diversity And Abundance Among Agricultural Land, Forested Land, And Their Ecotone In Guadalupe, Cerro Punta, Chiriquí Province, Republic Of Panamá., Stella Rae Kinard

Independent Study Project (ISP) Collection

As the human population increases, finding the balance between modifying land use for resources and protecting areas to preserve species that are threatened by anthropogenic disturbance is an ever growing problem. Guadalupe is a town in the Western Highlands of Panamá that struggles in this balance as its primary income source is agriculture, but it is located on the border of two protected areas, Parque Nacional La Amistad and Parque Nacional Volcán Barú. By understanding the unique ways in which avifauna utilize distinct vegetative landscapes, recommendations can be made for management styles of farms in Guadalupe to implement practices that …

Eurasian Aspen (Populus Tremula L.): Central Europe's Keystone Species 'Hiding In Plain Sight', Antonín Kusbach, Jan Šebesta, Robert Hruban, Pavel Peška, Paul C. Rogers

Aspen Bibliography

Knowledge of Eurasian aspen’s (Populus tremula L.) ecological and growth characteristics is of high importance to plant and wildlife community ecology, and noncommercial forest ecosystem services. This research assessed these characteristics, identified aspen’s habitat optimum, and examined causality of its current scarce distribution in central Europe. We analyzed a robust database of field measurements (4,656,130 stands) for forest management planning over 78,000 km² of the Czech territory. Our analysis we used GIS techniques, with basic and multivariate statistics such as general linear models, ordination, and classification. Results describe a species of broad ecological amplitude that has heretofore attracted …

Envisioning Transition From Open Landscapes To Forested Landscapes In The Routt National Forest, Colorado, United States, Brice B. Hanberry, Jacob M. Seidel

Aspen Bibliography

Globally, in remaining wildlands, tree densities and forested cover have increased in grasslands and open forests since European settlement. In the southern Rocky Mountains of Colorado, United States, we determined tree composition and tree cover from historical (years 1875 to 1896) surveys and compared them to current (2002 to 2011) tree composition and current (year 2016) forested land cover for 500,000 ha of the Routt National Forest. Additionally, we examined whether changes in precipitation occurred. Regarding composition, pine (primarily lodgepole pine; Pinus contorta) decreased from 65% to 32% of all trees, with increased subalpine fir (Abies lasiocarpa) …

Can The Impact Of Gravel Roads On Organic Layer Thickness Explain The Distribution Of Populus Tremuloides Along Road Networks In The Boreal Forest Of Eastern Canada?, Mathilde Marchais, Dominique Arseneault, Yves Bergeron

Aspen Bibliography

Roads are known to alter environmental conditions and the composition of road edge plant communities, particularly when exogenous materials are used as road surfacing. In this study, we evaluate the impact of gravel roads on the organic layer thickness (OLT) and aspen distribution in a boreal forest landscape of Eastern Canada. The OLT and aspen distribution were compared at different distances from the roads (0 m, 10 m, and >10 m) to determine whether a reduction in the OLT along the roads could explain the distribution of aspen along the road network, and in particular the role of the roads …

Oystershell Scale (Hemiptera: Diaspididae) Population Growth, Spread, And Phenology On Aspen In Arizona, Usa, Connor D. Crouch, Richard W. Hofstetter, Amanda M. Grady, Nylah N.S. Edwards, Kristen M. Waring

Aspen Bibliography

Oystershell scale (OSS; Lepidosaphes ulmi L.) is an invasive insect that threatens sustainability of aspen (Populus tremuloides Michx.) in the southwestern United States. OSS invasions have created challenges for land managers tasked with maintaining healthy aspen ecosystems for the ecological, economic, and aesthetic benefits they provide. Active management is required to suppress OSS populations and mitigate damage to aspen ecosystems, but before management strategies can be implemented, critical knowledge gaps about OSS biology and ecology must be filled. This study sought to fill these gaps by addressing 3 questions: (i) What is the short-term rate of aspen mortality in …

Pile Burning After Conifer Removal From Aspen Stands Affects Tree Mortality, Regeneration, And Understory Recovery, John-Pascal Berrill, Christa M. Dagley, Yoon G. Kim, J. Morgan Varner

Aspen Bibliography

Quaking aspen (Populus tremuloides Michx.) stands throughout the western United States provide valuable ecosystem services but can be lost via succession from aspen to conifer. Forest managers are cutting conifers, but disposal of cut wood can be challenging in remote or sensitive areas. Piling and burning is being tested within aspen stands but ecosystem responses to this treatment are understudied. We assessed aspen tree mortality, tree regeneration, and understory vegetation after forest restoration thinning followed by pile burning in seven aspen-conifer stands around Lake Tahoe, California and Nevada, USA. Pile burning was conducted after cut wood had dried (1.5–7.5 …

Aspen Recovery In Northern Yellowstone: A Comment On Brice Et Al. (2021), Luke E. Painter, Robert L. Beschta, William J. Ripple

Aspen Bibliography

Aspen sapling recruitment increased as browsing by elk decreased, following the 1995–96 reintroduction of wolves in Yellowstone National Park. We address claims by Brice et al. (2021) that previous studies exaggerated recent aspen recovery. We conclude that their results actually supported previous work showing a trophic cascade benefiting aspen.

Aspen And Spruce Densities Affect Tree Size, Future Stand Volume, And Aboveground Carbon Following Precommercial Thinning, Philip G. Comeau, Mike Bokalo

Aspen Bibliography

Data collected over a 30-year period from an experiment replicated across 21 locations in western Canada are used to explore the effects of precommercial thinning of trembling aspen to a range of densities in combination with three initial white spruce densities on tree growth and stand dynamics. Increasing differentiation amongst the 15 treatments was observed with age after thinning for both spruce and aspen responses. Spruce height and diameter declined with increasing aspen density. At age 10 spruce diameter with no aspen was 1.5× that of spruce in unthinned while it was 2.6× that of spruce in unthinned at age …

Tracing The Maternal Line In Glacial-Interglacial Migrations Of Populus Tremuloides: Finding Trees For Future Sustainable Forests By Searching In The Past, Luke R. Tembrock, Frida A. Zink, Guozhe Zhang, Andrea Schuhmann, Cuihua Gu, Zhiqiang Wu

Aspen Bibliography

Maintaining and planting sustainable forests is fundamental in perpetuating the essential functions of these ecosystems. A central aspect of managing forests for future resilience is the consideration of past migration and evolution of trees using genetic and genomic data to ensure that functionally appropriate diversity is conserved and utilized. In our study, we generated and compared genetic and genomic data from the plastome to better understand phylogeography and molecular evolution in the tree species Populus tremuloides (aspen). With these analyses, we found evidence of divergence and migration between northern and southern sites. Additionally, evidence of deep incomplete plastome sorting across …

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

Human wildlife interactions (HWI) pose a complex challenge for wildlife managers. Human encroachment into wildlife habitat and the growing number of outdoor recreationists are increasing the frequency of contact and conflict, especially in regions such as the Front Range of Colorado. Geographic information systems (GIS), which use a combination of remote sensing and environmental survey data, allow for predictive spatial analyses of where human wildlife interactions are likely to occur. I used publicly reported observations of moose to create spatial predictive maps in a species distribution model framework. Slope and elevation were shown to be the strongest predictors of HWI, …

Aspen Forest Condition Assessment And Restoration Guidance, Paul C. Rogers

Aspen Bibliography

This preliminary report is the first installment of an ongoing aspen assessment at Bryce Canyon National Park (BCNP). Over a 1.5-year period beginning in 2021, I assembled available BCNP and conducted a preliminary field survey to gain a better understanding of the quaking aspen (Populus tremuloides) resource within the Park. Findings suggest a long history of vegetation mapping with mixed results in terms of highlighting aspen presence a notable species of overall low coverage as well as aspen importance, at BCNP. In brief, though this species has limited presence, it is of high biodiversity conservation value. According to …

Cyp6g2 Is The Major P450 Epoxidase Responsible For Juvenile Hormone Biosynthesis In Drosophila Melanogaster, Qiangqiang Jia, Liu Yang, Jiamin Wen, Suning Liu, Di Wen, Wei Luo, Weihua Wang, Subba R. Palli, Li Sheng

Entomology Faculty Publications

Background Juvenile hormones (JH) play crucial role in regulating development and reproduction in insects. The most common form of JH is JH III, derived from MF through epoxidation by CYP15 enzymes. However, in the higher dipterans, such as the fruitfly, Drosophila melanogaster, a bis-epoxide form of JHB3, accounted most of the JH detected. Moreover, these higher dipterans have lost the CYP15 gene from their genomes. As a result, the identity of the P450 epoxidase in the JH biosynthesis pathway in higher dipterans remains unknown.

Results In this study, we show that Cyp6g2 serves as the major JH epoxidase responsible for …

Go West: Population Genomics Reveals Unexpected Population Fluctuations And Little Gene Flow In Western Hemisphere Populations Of The Predatory Lady Beetle, Hippodamia Convergens, Arun Sethuraman, Schyler O. Nunziata, Angela Jones, John J. Obrycki, David W. Weisrock

Entomology Faculty Publications

Hippodamia convergens—the convergent lady beetle, has been used extensively in aug- mentative biological control of aphids, thrips, and whiteflies across its native range in North America, and was introduced into South America in the 1950s. Overwintering H. convergens populations from its native western range in the United States are com- mercially collected and released across its current range in the eastern USA, with little knowledge of the effectiveness of its augmentative biological control. Here we use a novel ddRADseq-based SNP/haplotype discovery approach to estimate its range- wide population diversity, differentiation, and recent evolutionary history. Our results indicate (1) significant population …

The Mechanoreceptor Piezo Is Required For Spermatogenesis In Bombyx Mori, Zhongjie Zhang, Xiaojing Liu, Bo Hu, Kai Chen, Ye Yu, Chenxin Sun, Dalin Zhu, Hua Bai, Subba Reddy Palli, Anjiang Tan

Entomology Faculty Publications

Background The animal sperm shows high diversity in morphology, components, and motility. In the lepidopteran model insect, the silkworm Bombyx mori, two types of sperm, including nucleate fertile eupyrene sperm and anucleate unfertile apyrene sperm, are generated. Apyrene sperm assists fertilization by facilitating the migration of eupyrene spermatozoa from the bursa copulatrix to the spermatheca. During spermatogenesis, eupyrene sperm bundles extrude the cytoplasm by peristaltic squeezing, while the nuclei of the apyrene sperm bundles are discarded with the same process, forming matured sperm.

Results In this study, we describe that a mechanoreceptor BmPiezo, the sole Piezo ortholog in B. mori, …

From The Ground Up: A Complex Systems Approach To Climate Change Adaptation In Agriculture, Karen Buchsbaum

Antioch University Dissertations & Theses

Climate change presents an unprecedented challenge to global agriculture and food security. Small farms are especially vulnerable to the local impacts of large-scale drivers of change. Effective adaptation in agriculture requires working across scales, and geographic, political, and disciplinary boundaries to address barriers. I use elements of case study, agent-based modeling and serious games, to design a model of farmer decision-making using the sociocognitive framework of climate change adaptation. I examine how adaptation functions as a process, how complex dynamics influence farmer behavior, and how individual decisions influence collective behavior in response to climate change. This novel approach to adaptation …

Flashtags: Evaluating A Novel Deterrent To Reduce Livestock Depredation, C. Aaron Bott, Stewart W. Breck, Tom W. Murphy, Brad A. Freking, Carlos A. López González, David Prause, Corey Peavey, Albert Sommers, Coke Landers, Julie K. Young

Human–Wildlife Interactions

Social tolerance of carnivores can be improved by preventing conflicts through nonlethal predator deterrents (e.g., livestock protection dogs [Canis lupus familiaris] and human presence) that have been used for centuries. However, many livestock producers feel the existing preventative methods are inadequate for extensive production systems where livestock can be spread widely and have less human supervision. To address this issue, we developed and tested a new nonlethal tool called FlashTags to reduce livestock predation. FlashTags are ear tags worn by livestock that flash a random-light pattern at night when motion-triggered. In the first year, we tested the devices …

Waterbird-Perceived Damage, Control Measures, And Economic Implications For Rice Production In The Brazilian Cerrado, Demetrio Luis Guadagnin, Alexandre Afonso Meyer, João Augusto Rossi Borges, Fernanda Maia Justo

Human–Wildlife Interactions

Waterbirds have the potential to inflict economic damage to crops. However, is rice (Oryza sativa) production in the Brazilian Cerrado significantly affected by waterbirds? This study aimed to assess the extent of waterbird damage on irrigated rice production in Central Brazil. We conducted surveys of waterbird populations in rice agroecosystem habitats throughout the cultivation cycle and analyzed the expenses associated with waterbird-induced yield losses and the control measures employed by farmers. The 2 most prevalent waterbird species observed were Dendrocygna viduatta and D. autumnalis, comprising 68.6% of all recorded waterbirds. These species were more frequently encountered and …

Barn Owls Exert Top-Down Effects On The Abundance And Behavior Of Rodent Pests, Katherine C. Larson

Cal Poly Humboldt theses and projects

Predators can exert top-down effects on their prey by direct consumption, by imposing risk of predation, or a combination of both. However, empirical evidence for these effects is mixed and inconsistent. Barn owls in agriculture present a system with attributes that should, according to theory, lead to strong top-down effects, but research is limited and the distinction between effects on prey abundance and behavior remains unresolved. Understanding the top-down effect of predators on pests is a cornerstone of integrated pest management and important where barn owls may contribute to the control of rodents on farms. Vegetation can mediate the top-down …