Ecology and Evolutionary Biology Commons^™

A Review On The Invasion Ecology Of Amur Honeysuckle (Lonicera Maackii, Caprifoliaceae), A Case Study Of Ecological Impacts At Multiple Scales, Rachel E. Mcneish, Ryan W. Mcewan

Biology Faculty Publications

Invasive species are of global importance because of their impacts on ecological communities, habitat structure, native community dynamics, and ecosystem processes and function. Scientists and conservation managers are increasingly focusing on the biological impacts of invasive species and on devising management practices that emphasize the health of ecosystems based on measured biological processes. Amur honeysuckle (Lonicera maackii (Rupr.) Herder) is a highly successful invasive shrub in forests of eastern North America. The scientific literature surrounding this species has grown in the past several decades as researchers have investigated L. maackii impacts across multiple ecological scales. In this review we …

Functional Diversity Of Small And Large Trees Along Secondary Succession In A Tropical Dry Forest, Lucía Sanaphre-Villanueva, Juan Manuel Dupuy, José Luis Andrade, Casandra Reyes-García, Horacio Paz, Paula C. Jackson

Faculty Articles

Functional Diversity is considered an important driver of community assembly in environmental and successional gradients. To understand tree assembly processes in a semideciduous tropical forest, we analyzed the variation of Functional Richness (FRic), Functional Divergence (FDiv), and Functional Evenness (FEve) of small vs. large trees in relation to fallow age after slash-and-burn agriculture and topographical position (flat sites vs. hills). FRic of small trees was lower than null model predicted values across the successional gradient, and decreased unexpectedly in older successional ages. FRic of large trees was higher than null model predictions early in succession and lower in late-successional stands …

Thirty Years Of Compositional Change In An Old-Growth Temperate Forest: The Role Of Topographic Gradients In Oak-Maple Dynamics, Julia I. Chapman, Ryan W. Mcewan

Biology Faculty Publications

Ecological communities are structured in response to spatial and temporal variation of numerous factors, including edaphic conditions, biotic interactions, climatic patterns and disturbance regimes. Widespread anthropogenic factors such as timber harvesting can create long-lasting impacts, obscuring the relationship between community structure and environmental conditions. Minimally impacted systems such as old-growth forests can serve as a useful ecological baseline for predicting long-term compositional shifts. We utilized decadal tree species sampling data (1979–2010) divided into three strata (understory, midstory, overstory) to examine temporal changes in relative abundances and spatial distributions of dominant taxa, as well as overall shifts in community composition, in …

Disease Introduction Is Associated With A Phase Transition In Bighorn Sheep Demographics, Kezia R. Manlove, E. Frances Cassirer, Paul C. Cross, Raina K. Plowright, Peter J. Hudson

Wildland Resources Faculty Publications

Ecological theory suggests that pathogens are capable of regulating or limiting host population dynamics, and this relationship has been empirically established in several settings. However, although studies of childhood diseases were integral to the development of disease ecology, few studies show population limitation by a disease affecting juveniles. Here, we present empirical evidence that disease in lambs constrains population growth in bighorn sheep (Ovis canadensis) based on 45 years of population‐level and 18 years of individual‐level monitoring across 12 populations. While populations generally increased (λ = 1.11) prior to disease introduction, most of these same populations experienced an abrupt change …

Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson

Master's Theses

It is widely accepted that allelopathy is not only significant, but more or less singular, in the inhibition of understory vegetation in California Eucalyptus globulus (blue gum) plantations. However, there is no published documentation of allelopathy by blue gums against California native species. Here, we present evidence that germination and early seedling growth of five California native species are not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels. In the greenhouse, seeds were germinated in field-collected soil from mature blue gum plantations and the adjacent native, coastal scrub communities. In petri plates, seeds …

The Plight Of Aspen: Emerging As A Beneficiary Of Wolf Restoration On Yellowstone’S Northern Range, John Klaptosky

Aspen Bibliography

No abstract provided.

Quantitative Evidence For The Effects Of Multiple Drivers On Continental-Scale Amphibian Declines, Evan H. Campbell Grant, David A. W. Miller, Benedikt R. Schmidt, Michael J. Adams, Staci M. Amburgey, Thierry Chambert, Sam S. Cruickshank, Robert N. Fisher, David M. Green, Blake R. Hossack, Pieter T. J. Johnson, Maxwell B. Joseph, Tracy A. G. Rittenhouse, Maureen E. Ryan, J. Hardin Waddle, Susan C. Walls, Larissa L. Bailey, Gary M. Fellers, Thomas A. Gorman, Andrew M. Ray, David S. Pilliod, Steven J. Price, Daniel Saenz, Walt Sadinski, Erin Muths

Forestry and Natural Resources Faculty Publications

Since amphibian declines were first proposed as a global phenomenon over a quarter century ago, the conservation community has made little progress in halting or reversing these trends. The early search for a “smoking gun” was replaced with the expectation that declines are caused by multiple drivers. While field observations and experiments have identified factors leading to increased local extinction risk, evidence for effects of these drivers is lacking at large spatial scales. Here, we use observations of 389 time-series of 83 species and complexes from 61 study areas across North America to test the effects of 4 of the …

The Mexican Water Forest: Benefits Of Using Remote Sensing Techniques To Assess Changes In Land Use And Land Cover, Maria F. Lopez Ornelas

Master's Projects and Capstones

In the past 30 years, anthropogenic activities like urbanization, agriculture, road fragmentation and deforestation have resulted in changes in the land use and land cover (LULC) in the Mexican Water Forest. Due to the important ecosystem services, and the natural resources this forest provides, in Mexico, it has become increasingly necessary to use new technologies and tools to support the planning, implementation and integration of forest management and conservation plans, as well as ecological and socioeconomic analysis of this ecosystem. Remote Sensing techniques and Geographic Information Systems (GIS) have been a true technological and methodological revolution in the acquisition, management …

Hands Of The Future, Inc; Junior Nature Club; Living Schoolyards, Zonda K. Bryant

Purdue P-12 Networking Summit & Poster Session

Programs to connect children to nature

A Multiple‐Scale Assessment Of Long‐Term Aspen Persistence And Elevational Range Shifts In The Colorado Front Range, Mario Bretfeld, Scott B. Franklin, Robert K. Peet

Aspen Bibliography

Aspen forests and woodlands are some of the most species‐rich forest communities in the northern hemisphere. Changing climate, altered disturbance regimes, land use, and increased herbivore pressure threaten these forests both in Eurasia and North America. In addition, rapid mortality dubbed “Sudden Aspen Decline” is a concern for aspen's long‐term presence in the western United States, especially Colorado and Utah. Yet it is still unclear whether aspen is persistent or declining at the landscape scale. We assessed aspen persistence at different spatial scales in the Colorado Front Range by resampling 89 plots containing aspen from among 305 vegetation plots sampled …

Determining The Pollination Mechanism Of A Problematic Invasive Species In The Gulf South: Triadica Sebifera, Jennifer Wester Clark

LSU New Orleans Theses and Dissertations

Understanding the ecology of invasive species is vital to curb the homogenizing of ecosystems, yet the pollination mechanisms of the Chinese tallow tree (Triadica sebifera) in its introduced habitat remain ambiguous. This study examines self-pollination, wind pollination, and flower-visiting insects of tallow in a bottomland hardwood forest and Longleaf pine savannah in the U.S. Gulf South. These data suggest that self-pollination and airborne pollination are possible, but likely rare occurrences, although the possibility of apoxisis was not investigated. Seed production in exclusion experiments was significantly less than in open-pollinated flowers, and wind dispersal of tallow pollen dropped to …

Changes In Floristic Composition In The State Forests In Worcester County (Massachusetts) Over 34 Years, Flor A. Monroe

Sustainability and Social Justice

ABSTRACT

CHANGES IN FOREST DIVERSITY OF STATE FOREST IN WORCESTER COUNTY, MASSACHUSETTS, OVER 34 YEARS PERIOD

The forest in Massachusetts has changed since the earliest colonial settlement and today the floristic composition is more homogeneous. This study investigates the potential change in the floristic composition over thirty years in Worcester County State Forests. Shannon, richness and evenness indices for two periods were compared, and Jaccard index was used to analyze similarity in composition between the periods. The possible influence of severe weather events was also analyzed.

It was found Changes in the floristic composition, but the magnitude of the changes …

Emergence Phenology And Nematode Associates Of The Woodwasp, Sirex Nigricornis F. (Hymenoptera: Siricidae), In Arkansas And Mississippi Forests, Jessica Ann Hartshorn

Graduate Theses and Dissertations

Sirex nigricornis F. (Hymenoptera: Siricidae) is a native woodwasp in eastern North America that inhabits dead and dying pine trees during its univoltine development. Sirex noctilio is native to Eurasia and North Africa and was discovered in the northeastern United States in 2004 after a century of accidental introductions across the Southern Hemisphere. Since then, it has spread to seven states and southern Ontario. There is concern about its potential to negatively affect the multi-billion dollar pine timber industry of the southeastern United States. Effective monitoring tools are necessary to track the spread and establishment of S. noctilio. Deladenus siricidicola …

“One Health” Or Three? Publication Silos Among The One Health Disciplines, Kezia R. Manlove, Josephine G. Walker, Meggan E. Craft, Kathryn P. Huyvaert, Maxwell B. Joseph, Ryan S. Miller, Pauline Nol, Kelly A. Patyk, Daniel O'Brien, Daniel P. Walsh, Paul C. Cross

Wildland Resources Faculty Publications

The One Health initiative is a global effort fostering interdisciplinary collaborations to address challenges in human, animal, and environmental health. While One Health has received considerable press, its benefits remain unclear because its effects have not been quantitatively described. We systematically surveyed the published literature and used social network analysis to measure interdisciplinarity in One Health studies constructing dynamic pathogen transmission models. The number of publications fulfilling our search criteria increased by 14.6% per year, which is faster than growth rates for life sciences as a whole and for most biology subdisciplines. Surveyed publications clustered into three communities: one used …

Ecological Studies Of Wolves On Isle Royale, 2015-2016, Rolf O. Peterson, John A. Vucetich

Ecological Studies of Wolves on Isle Royale

Annual Report 2015-2016

Gibsonville Healthy Forest Restoration Project: Silviculture Report, Dan Roskopf

Aspen Bibliography

The Forest Service proposes to reduce the risk of wildfire, to protect, restore, and enhance forest ecosystem components (i.e., streams, meadows, aspen areas) in the vicinity of Gibsonville, California. A combination of hazard tree removal, forest health, and fuels reduction treatments are proposed on 1,200 acres of Forest Service system lands. These actions are proposed to be implemented on the Feather River Ranger District of the Plumas National Forest.

The Use Versus Availability Of Wood Extraction At The Baga Ii Forest Reserve Border Adjacent To Kizanda Village In The West Usambara Mountains, Tanzania, Rebecca Halter

Independent Study Project (ISP) Collection

Tropical forests, especially in developing countries, continue to face serious threats of deforestation due to human pressures and poor management. These forests are at risk of disappearing and taking their water catchment and ecosystem services with them. Kizanda Villagers’ illegal woodfuel and polewood extraction poses a threat to the future health and existence of the Baga II Forest. This study, conducted from April 5th to April 19th, 2016, aimed to examine the use versus availability of tree species along the forest border. Twenty disturbance transects, each 4 meters wide, were conducted perpendicular to the Baga II forest border. The transects …

Seed Dispersal: A Tale Of Two Species, W. John Hayden

Biology Faculty Publications

Orchids have minute, dustlike seeds. In this respect, Goodyera pubescens (Downy Rattlesnake Plantain), the 2016 VNPS Wildflower of the Year, is a typical orchid. Like all other orchids, Goodyera seeds contain little more than a few embryonic cells enclosed in a thin seed coat. There are two advantages to small seed size in orchids: minute seeds can be produced in prodigious quantities, and they can disperse over great distances by wind.

Recovery Of Forest Floor Diversity After Removal Of The Nonnative, Invasive Plant Euonymus Fortunei, Kali Z. Mattingly, Ryan W. Mcewan, Robert D. Paratley, Sarah R. Bray, James R. Lempke, Mary A. Arthur

Biology Faculty Publications

The vine Euonymus fortunei (Turcz.) Hand.-Mazz. is invading forests of the eastern United States; as a result, removal of E. fortunei has become a priority of resource managers. This study examined the effectiveness of five techniques for eliminating E. fortunei, restoring plant species richness, and enhancing recolonization by woody species. In 2003, the following five treatments were applied: burn with a propane torch, light exclusion by plastic tarp, burn and glyphosate application, cut (simulated grazing) and glyphosate application, mow and glyphosate application, plus an untreated control. Each treatment was replicated four times in a randomized block design located in …

Assessing How Disruption Of Methanogenic Communities And Their Syntrophic Relationships In Tidal Freshwater Marshes Via Saltwater Intrusion May Affect Ch4 Emissions, David J. Berrier, Scott C. Neubauer, Rima B. Franklin

Rice Rivers Center Research Symposium

Tidal freshwater wetlands (TFW), which lie at the interface of saltwater and freshwater ecosystems, are predicted to experience moderate salinity increases due to sea level rise. Increases in salinity generally suppress CH4 production, but it is uncertain to what extent elevated salinity will affect CH4 cycling in TFW. It is also unknown whether CH4 production will resume when freshwater conditions return. The ability to produce CH4 is limited to a monophyletic group of the Euryarchaeota phylum called methanogens (MG), who are limited to a small number of substrates (e.g., acetate, H2, and formate) produced from the breakdown of fermentation products. …

Using The Past To Restore The Future: Quantifying Historical Vegetation To Assist In Tidal Freshwater Wetland Restoration, Christopher D. Gatens, Richard Ward, Edward R. Crawford

Rice Rivers Center Research Symposium

Wetlands have been providing humans with critical natural ecosystem services throughout our time on Earth. Nevertheless, these invaluable ecosystems have been habitually altered as a cost of human progression. Two of the most common alterations to wetlands are hydrologic, in the form of damming, and filling. Both occurred along Kimages Creek in Charles City County, VA during the 19th and 20th centuries. In 2010 the Lake Charles dam was partially removed, restoring the creek's tidal communication with the James River and beginning tidal forested freshwater wetland restoration. Upon the recession of the body of water, numerous woody stumps were revealed.

Tower-Based Greenhouse Gas Fluxes In A Restored Tidal Freshwater Wetland: A Shared Resource For Research And Teaching., Ellen J. Stuart-Haëntjens, Scott C. Neubauer, Christopher M. Gough

Rice Rivers Center Research Symposium

The goals of this study are: 1) to use an eddy-covariance system to continuously measure wetland-atmosphere CO2 and CH4 exchange in a restored forested wetland, 2) to quantity C sequestration in plant biomass and soils in restored (Kimages Creek watershed) and old-growth (Harris Creek watershed) forested wetlands, and 3) to establish a shared long-term, shared research and teaching platform centered on eddy-covariance tower measurements. Since the old-growth forest wetland has had longer to accumulate C, the current C stocks are likely much larger than those of the restored wetland; however, the rate of C accumulation (i.e., C sequestration or net …

Bigtooth And Quaking Aspen Propagation From Roots Versus Seed, Joseph M. Vande Hey

Aspen Bibliography

No abstract provided.

High And Dry: Post-Fire Tree Seedlingestablishment In Subalpine Forestsdecreases With Post-Fire Drought Andlarge Stand-Replacing Burn Patches, Brian J. Harvey, Daniel C. Donato, Monica G. Turner

Aspen Bibliography

Aim: Climate warming and increased wildfire activity are hypothesized to catalyse biogeographical shifts, reducing the resilience of fire-prone forests world-wide. Two key mechanisms underpinning hypotheses are: (1) reduced seed availability in large stand-replacing burn patches, and (2) reduced seedling establishment/survival after post-fire drought. We tested for regional evidence consistent with these mechanisms in an extensive fire-prone forest biome by assessing post-fire tree seedling establishment, a key indicator of forest resilience.

Location: Subalpine forests, US Rocky Mountains.

Methods: We analysed post-fire tree seedling establishment from 184 field plots where stand-replacing forest fires were followed by varying post-fire climate conditions. Generalized linear …

Effects Of Mountaintop Removal Mining On Population Dynamics Of Stream Salamanders, Sara B. Freytag

Theses and Dissertations--Forestry and Natural Resources

Mountaintop removal mining (MTR) is a notorious stressor of stream ecosystems in the Central Appalachians. Valley fills (VF) lead to reduced occupancy, abundance, and species richness of stream salamanders. Multiple factors may be responsible for these reductions, but specifically habitat fragmentation and degradation may reduce colonization rates and increase local extinction rates. From 2013-2015, repeated counts of salamanders were conducted in stream reaches impacted by MTR/VF and compared to counts in reference reaches to answer the question: do stream salamander population dynamics differ between stream reaches impacted by MTR/VF and reference stream reaches? I also investigated dynamics of stream habitat …

Synthesis Of Satellite Microwave Observations For Monitoring Global Land-Atmosphere Co2 Exchange, Lucas Alan Jones

Graduate Student Theses, Dissertations, & Professional Papers

This dissertation describes the estimation, error quantification, and incorporation of land surface information from microwave satellite remote sensing for modeling global ecosystem land-atmosphere net CO₂ exchange. Retrieval algorithms were developed for estimating soil moisture, surface water, surface temperature, and vegetation phenology from microwave imagery timeseries. Soil moisture retrievals were merged with model-based soil moisture estimates and incorporated into a light-use efficiency model for vegetation productivity coupled to a soil decomposition model. Results, including state and uncertainty estimates, were evaluated with a global eddy covariance flux tower network and other independent global model- and remote-sensing based products.

Forest Stand Structure And Primary Production In Relation To Ecosystem Development, Disturbance, And Canopy Composition, Cynthia M. Scheuermann

Theses and Dissertations

Temperate forests are complex ecosystems that sequester carbon (C) in biomass. C storage is related to ecosystem-scale forest structure, changing over succession, disturbance, and with community composition. We quantified ecosystem biological and physical structure in two forest chronosequences varying in disturbance intensity, and three late successional functional types to examine how multiple structural expressions relate to ecosystem C cycling. We quantified C cycling as wood net primary production (NPP), ecosystem structure as Simpson’s Index, and physical structure as leaf quantity (LAI) and arrangement (rugosity), examining how wood NPP-structure relates to light distribution and use-efficiency. Relationships between structural attributes of biodiversity, …

Early Seral Mixed-Conifer Forest Structure And Composition Following A Wildfire Reburn In The Sierra Nevada, Erin Alvey

Cal Poly Humboldt theses and projects

Before the era of modern fire suppression, California’s northern Sierra Nevada mixed-conifer and yellow pine forests were self-regulating; recurring short-interval, low-mixed severity wildfires maintained forest structure and composition, which in turn exerted bottom-up controls on subsequent wildfires. As a result of fire suppression, and coupled with the effects of climate warming and other anthropogenic disturbances, the fundamental structure of mixed-conifer and yellow pine forests has shifted. Wildfires may now be increasing in size, severity, and frequency across western North America. However, little is known about the post-fire impacts of repeat wildfire on a forest after a long era of suppression. …

Restoration Of A Wet Longleaf Pine (Pinus Palustris) Savanna In Southeast Louisiana: Burning Toward Reference Conditions, Alex K. Entrup

LSU New Orleans Theses and Dissertations

This study quantifies the changes in vegetation composition and structure of a fire-excluded Pinus palustris (longleaf pine) wetland savanna restoration site in southeastern in comparison to a proximate contemporary reference site. The restoration site was invaded by hardwood species and off-site pines, and never underwent extensive soil disturbance. The restoration treatments involved logging across portions of the site and the reintroduction of fire across the entire site. All species present in 10m² quadrats were recorded prior to treatment and throughout the 17 year study at reference and treatment sites. The community composition of both logged and unlogged sites converged …

Research Notes Lower Prairie Creek Project Redwood National Park, Susie Van Kirk

Susie Van Kirk Papers

Project Description: to conduct Phase 1 of a narrative history project for the Lower Prairie Creek Watershed, funded by Save the Redwoods League. Phase1 of this project will be to compile reference materials, sources, conduct scoping with NPS staff and other local stakeholders to develop historical research themes that will be needed for a future narrative history of the Lower Prairie Creek Watershed. It will result in a detailed chapter outline to be submitted to NPS.