Forest Biology Commons^™

Spatial Distribution Of Earthworms In An East Texas Forest Ecosystem, Melissa A. Bozarth, Kenneth W. Farrish, George A. Damoff, James Van Kley, J. Leon Young

Faculty Publications

Earthworms were collected and identified in different ecological habitats of the Stephen F. Austin Experimental Forest (SFAEF) in the Piney Woods Ecoregion (PWE) of Texas. Earthworm spatial distribution data were collected over four distinct ecological habitats with a range of soil conditions and vegetative cover. A total of 128 sampling plots were surveyed in two different, broadly defined locations (mesic slope = 68 plots, dry-mesic upland = 60 plots). Using multivariate classification/ordination (TWINSPAN) and detrended correspondence analysis (DCA) of overstory vegetation data, these two locations were further divided into four distinct habitats: dry-mesic mixed upland, transitional zone, mesic slope and …

Phylogenetic Analyses Of Andean And Amazonian Tree Communities In Ecuador, Samantha J. Worthy

Theses and Dissertations

The forests of Ecuador are known for their high levels of diversity and endemism, classifying the country as a biodiversity hotspot. Both the western Amazon and Andean montane forests are richly populated with tropical tree species that have been little studied in a community phylogenetic context. The implementation of elevational transects and trait based analyses having proven useful in gaining a better understanding of how environmental factors are affecting the tree community structure in these habitats. The goal of this research was to evaluate the magnitude ofDNA barcode diversity among Amazonian and Andean tree species. Specifically, the objectives were to …

Twenty-Five Year Response Of The Herbaceous Layer Of A Temperate Hardwood Forest To Elevated Nitrogen Deposition, Frank S. Gilliam, Nicole Turrill Welch, Anne Hockenberry Phillips, Jake H. Billmyer, William T. Peterjohn, Zachariah K. Fowler, Christopher A. Walter, Mark B. Burnham, Jeffrey D. May, Mary Beth Adams

Biological Sciences Faculty Research

Increasing rates of atmospheric deposition of nitrogen (N) present a novel threat to the biodiversity of terrestrial ecosystems. Many forests are particularly susceptible to excess N given their proximity to sources of anthropogenic N emissions. This study summarizes results of a 25-yr treatment of an entire central Appalachian hardwood forest watershed via aerial applications of N with a focus on effects of added N on the cover, species richness, and composition of the herbaceous layer. Research was carried out on two watersheds of the Fernow Experimental Forest (FEF), West Virginia. The long-term reference watershed at FEF (WS4) was used as …

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. …

Demography And Disease Of The Rare Shrub Buckleya Distichophylla (Santalaceae) In Northeastern Tennessee, William Seth Ratliff

Undergraduate Honors Theses

Piratebush (Buckleya distichophylla (Nutt.) Torr.) is a rare, hemiparasitic shrub with the only extant populations in western North Carolina, northeastern Tennessee, and southwestern Virginia. The preferred natural hosts of piratebush, Carolina and eastern hemlocks, have seen sharp declines over the last decade due to the invasive hemlock woolly adelgid. Virginia pine, another important host of piratebush, is also susceptible to disease, specifically Cronartium appalachianum, a rust fungus for which piratebush is the secondary host. This study described and analyzed current demographic parameters of three Tennessee piratebush populations. Additionally, spatial patterns of disease and demographic characters were analyzed. These …

Radiocarbon Isotopic Classification Of Deep Tropical Forest Soils, Brooke Butler, Karis J. Mcfarlane, Jennifer Pett-Ridge, Katherine A. Heckman

STAR Program Research Presentations

Tropical forest soils have an important role in global carbon (C) stocks. Small changes in the cycling of C could drastically affect atmospheric carbon dioxide (CO2) concentrations and active cycling of carbon in a forest community. Currently, little is understood of how tropical forest soils will respond to the increasing global temperatures. To examine the effects of warming/ drought on losses of older versus younger soil C pools, we implemented radiocarbon (14C) isotopic characterization of various soil plot samples and depths from the Luquillo Experimental Forest, Puerto Rico. 14C was measured using Accelerated Mass Spectrometry (AMS) from catalytically condensed carbon …

Fishing For A Sustainable Future: Aquaponics As A Method Of Food Production, Richard Ramsundar

Student Theses 2015-Present

This thesis compares and explains the advantages aquaponics farming has over modern industrial intensive farming. Through a comparison natural capital usage, conservation, recycling and cost, the thesis advocates for the expansion of aquaponics usage in urban settings. The thesis also explains the history of intensive farming and aquaponics in America, the science of how aquaponics operates, the economic and environmental costs of modern intensive farming versus aquaponics farming, and the social implications of aquaponics. Lastly, I propose a policy that reallocates farm subsidies by modifying the Farm Bill. Then I propose policies that support creating a new standard of farm …

Animal Habitat Utilization And The Impacts Of Small-Scale Disturbances On Vegetation Within Larch Forests In Northeastern Siberia, Aaron Phillip White

Theses and Dissertations - UTB/UTPA

Boreal forests support a variety of animals distributed across a matrix of habitat patches including forests of different ages and stand densities. These forests occur at high latitudes where cold and moist conditions favor ground layer dominance by mosses and slow decomposition rates, resulting in a thick soil organic layer (SOL) comprised primarily of decomposing mosses and roots. However, limited information is available on how animal use varies across habitat types in northeastern Siberia. Boreal forests of this region are unique because they are comprised of a single deciduous conifer, Cajander larch (Larix cajanderi). These forests also occur on a …

In Situ Nitrogen Mineralization, Nitrification, And Ammonia Volatilization In Maize Field Fertilized With Urea In Huanghuaihai Region Of Northern China, Xuelin Zhang, Qun Wang, Jun Xu, Frank S. Gilliam, Nicolas Tremblay, Chaohai Li

Biological Sciences Faculty Research

Nitrogen (N) fertilization potentially affects soil N mineralization and leaching, and can enhance NH₃ volatilization, thus impacting crop production. A fertilizer experiment with five levels of N addition (0, 79, 147, 215 and 375 kg N ha^-1) was performed in 2009 and 2010 in a maize field in Huanghuaihai region, China, where > 300 kg N ha^-1 has been routinely applied to soil during maize growth period of 120 days. Responses of net N mineralization, inorganic N flux (0–10cm), NH₃ volatilization, and maize yield to N fertilization were measured. During the growth period, net N mineralization …

Understory Diversity And Composition Drives Carabid Assemblages, Tierney Brosius, Michael Reisner

Biology: Faculty Scholarship & Creative Works

Fire suppression has nearly eliminated fire as a disturbance in temperate deciduous forests. Lack of fire is transforming these ecosystems through a positive feedback loop termed mesophication: cool, damp, shady conditions become continually more favorable for a few mesophytic species, while deteriorating for diverse array of heliophytic ones. Disturbances caused by urbanization fragment and degrade remnant forests. In urban settings, human management (or lack thereof) is often a dominate driver of succession. Carabid diversity, understory vegetation, patch size, patch connectivity, and permeable surface area were all examined in multiple forest plots in Rock Island and Moline. The result of this …

Amphibian And Small Mammal Assemblages In A Northern Virginia Forest Before And After Defoliation By Gypsy Moths (Lymantria Dispar), Joseph C. Mitchell

Virginia Journal of Science

The introduced European gypsy moth (Lymantria dispar) caused substantial defoliation and mortality of oak trees along the North Fork of Quantico Creek in Prince William Forest Park, Prince William County, Virginia, U.S.A., in 1989 and the early 1990s. Results of a drift fence/pitfall study conducted in 1988 were compared to those obtained from the same technique in the same areas in 1993 to elucidate whether the amphibian and small mammal assemblages had changed over time. Number of Lithobates sylvaticus increased significantly in 1993, but the numbers of Lithobates clamitans and Plethodon cinereus were significantly higher in 1988. Total …

A Novel Mechanism To Explain Success Of Invasive Herbaceous Species At The Expense Of Natives In Eastern Hardwood Forests, Frank S. Gilliam

Biological Sciences Faculty Research

Among the more intriguing topics in general ecology courses are the symbiotic relationships (the ‘-isms’ as I sometimes present them – mutualism, commensalism, and parasitism). Of these, mutualism is typically the most appealing to students. The scenario that different species can not only co-exist, but can also provide essential resources/services for one another, resonates well with all but the least interested in the course. Ultimately, however, there is also the palpable degree of dismay when they discover that these relationships arise from mutual exploitation, rather than from some benign force of nature. A flip-side of this, in many ways a …

The Impact Of Forest Successional Status On Community Structure Of Neotropical Cerambycid Beetles, Lin Li

Dissertations and Theses

Due to anthropogenic activities, tropical rain forests face many challenges in sustaining biodiversity and maintaining global climates. This project examines how forest successional status affects community composition of saproxylic cerambycids, which, as early colonists of moribund trees, have an important role in nutrient cycling. In the lowland rain forest of Costa Rica, thirty-nine trees in five plant families (Fabaceae, Lecythidaceae, Malvaceae, Moraceae, and Sapotaceae) were sampled in a mosaic of old growth and secondary forest. They yielded 3545 cerambycid individuals in 49 species. Species richness was almost identical in old growth and secondary forest; but abundance was higher in old-growth. …

Spatial Variation In Carbon And Nitrogen In Cultivated Soils In Henan Province, China: Potential Effect On Crop Yield, Xuelin Zhang, Qun Wang, Frank S. Gilliam, Yilun Wang, Feina Cha, Chaohai Li

Biological Sciences Faculty Research

Improved management of soil carbon (C) and nitrogen (N) storage in agro-ecosystems represents an important strategy for ensuring food security and sustainable agricultural development in China. Accurate estimates of the distribution of soil C and N stores and their relationship to crop yield are crucial to developing appropriate cropland management policies. The current study examined the spatial variation of soil organic C (SOC), total soil N (TSN), and associated variables in the surface layer (0–40 cm) of soils from intensive agricultural systems in 19 counties within Henan Province, China, and compared these patterns with crop yield. Mean soil C and …

Nitrogen Deposition Contributes To Soil Acidification In Tropical Ecosystems, Xiankai Lu, Qinggong Mao, Frank S. Gilliam, Yiqi Luo, Jiangming Mo

Biological Sciences Faculty Research

Elevated anthropogenic nitrogen (N) deposition has greatly altered terrestrial ecosystem functioning, threatening ecosystem health via acidification and eutrophication in temperate and boreal forests across the northern hemisphere. However, response of forest soil acidification to N deposition has been less studied in humid tropics compared to other forest types. This study was designed to explore impacts of long-term N deposition on soil acidification processes in tropical forests. We have established a long-term N deposition experiment in an N-rich lowland tropical forest of Southern China since 2002 with N addition as NH₄NO₃ of 0, 50, 100 and 150 kg …

Tree Height And Diameter Relationships Of White Pine And Tree Fall Patterns Of Red Pine In Northern Minnesota, Jake Mack

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Wire Netting Reduces African Elephant (Loxodonta Africana) Impact To Selected Large Trees In South Africa, Kelly Derham

Masters Theses & Specialist Projects

African elephants (Loxodonta africana) are ecosystem engineers in that they substantially alter the environment through their unique foraging and feeding habits. At high densities, elephants potentially have negative impacts on the environment, specifically to large trees. Because of this, recent increases of elephants in the Associated Private Nature Reserves (APNR) on the Western Boundary of Kruger National Park, South Africa have caused concern regarding the health of several species of tree. My objective was to assess the effectiveness of wrapping protective wire netting around the trunk of the tree in preventing and reducing bark stripping by elephants. 2,668 …

Effect Of Australian Pine (Casuarina Equisetifolia) Canopy Density On The Understory Plant Community On San Salvador, Bahamas, Jeffry Anderson, Anna Baumgartner

Celebrating Scholarship & Creativity Day (2011-2017)

Casuarina equisetifolia, or Australian pine, is an invasive angiosperm species on the island of San Salvador, The Bahamas. It was originally found only in Southeast Asia and Australia. This tree is unique in that its leaves are much reduced and occur in whorls around the photosynthetic branchlets. It has been established that this tree contributes to the increased erosion of sediment on the dunes of San Salvador (Sealey 1998). This study investigated several possible factors contributing to differences in the understory plant community which may contribute to this erosion including leaf litter density, shading, and soil pH. It is …

Stand Density And Age Affect Tree-Level Structural And Functional Characteristics Of Young, Postfire Lodgepole Pine In Yellowstone National Park, Paige E. Copenhaver-Parry, Daniel B. Tinker

Faculty Publications - Department of Biological & Molecular Science

More frequent fire activity associated with climate warming is expected to increase the extent of young forest stands in fire-prone landscapes, yet growth rates and biomass allocation patterns in young forests that regenerated naturally following stand-replacing fire have not been well studied. We assessed the structural and functional characteristics of young, postfire lodgepole pine (Pinus contorta var. latifolia) trees across the Yellowstone subalpine plateaus to understand the influence of postfire stand density and age on tree-level aboveground biomass (AB), component biomass (bole, branch, foliage), partitioning to components, tree-level aboveground net primary productivity (ANPP) and leaf area (LA). Sixty …

Examining Historical And Current Mixed-Severity Fire Regimes In Ponderosa Pine And Mixed-Conifer Forests Of Western North America, Dennis C. Odion, Chad T. Hanson, Andre Arsenault, William L. Baker, Dominick A. Dellasala, Richard L. Hutto, Walt Klenner, Max A. Moritz, Rosemary L. Sherriff, Thomas T. Veblen, Mark A. Williams

Biological Sciences Faculty Publications

There is widespread concern that fire exclusion has led to an unprecedented threat of uncharacteristically severe fires in ponderosa pine (Pinus ponderosa Dougl. ex. Laws) and mixed-conifer forests of western North America. These extensive montane forests are considered to be adapted to a low/moderate-severity fire regime that maintained stands of relatively old trees. However, there is increasing recognition from landscape-scale assessments that, prior to any significant effects of fire exclusion, fires and forest structure were more variable in these forests. Biota in these forests are also dependent on the resources made available by higher-severity fire. A better understanding of …

Invasive Plant Erodes Local Song Diversity In A Migratory Passerine, Yvette K. Ortega, Aubree Benson, Erick Greene

Biological Sciences Faculty Publications

Exotic plant invasions threaten ecosystems globally, but we still know little about the specific consequences for animals. Invasive plants can alter the quality of breeding habitat for songbirds, thereby impacting important demographic traits such as dispersal, philopatry, and age structure. These demographic effects may in turn alter song-learning conditions to affect song structure and diversity. We studied Chipping Sparrows (Spizella passerina) breeding in six savannas that were either dominated by native vegetation or invaded by spotted knapweed (Centaurea stoebe), an exotic forb known to diminish food resources and reproductive success. Here, we report that the prevalence of older birds was …

Avoidance Of Canopy Gaps By A Common Land Snail, Christopher P. Bloch, Michael Stock

Biological Sciences Faculty Publications

Because canopy gaps are characterized by elevated temperature and decreased humidity relative to closed-canopy forest, terrestrial gastropods may be exposed to greater desiccation stress in gaps than in undisturbed forest. We placed individuals of Caracolus caracolla at the edges of canopy gaps in montane forest in Puerto Rico and observed their movements. Individuals preferentially moved out of gaps except in one gap on the first night of the study, and the proportion of individuals recaptured inside gaps decreased over time. Individuals moved, on average, farther into forest than into gaps. Juveniles and adults responded similarly. These results suggest that C. …

Nutrient Limitation In Three Lowland Tropical Forests In Southern China Receiving High Nitrogen Deposition: Insights From Fine Root Responses To Nutrient Additions, Feifei Zhu, Muneoki Yoh, Frank S. Gilliam, Xiankai Lu, Jiangming Mo

Biological Sciences Faculty Research

Elevated nitrogen (N) deposition to tropical forests may accelerate ecosystem phosphorus (P) limitation. This study examined responses of fine root biomass, nutrient concentrations, and acid phosphatase activity (APA) of bulk soil to five years of N and P additions in one old-growth and two younger lowland tropical forests in southern China. The old-growth forest had higher N capital than the two younger forests from long-term N accumulation. From February 2007 to July 2012, four experimental treatments were established at the following levels: Control, N-addition (150 kg N ha^–1 yr^–1), P-addition (150 kg P ha^–1 yr^{–1 …}

Residential Edges As Ecological Traps: Postfledgling Survival Of A Ground-Nesting Passerine In A Forested Urban Park, Amy A. Shipley, Michael T. Murphy, Adam H. Elzinga

Biology Faculty Publications and Presentations

Substantial offspring mortality can occur during the postfledging period of birds, but few postfledging survival studies have been conducted within the context of habitat suitability. We conducted a 2-year radiotelemetry study of Spotted Towhee (Pipilo maculatus) reproductive success and fledgling survival in a 24-ha forested park in a residential area of Lake Oswego, Oregon. In corroboration of previous research on this species, we found (1) that Spotted Towhees nested closer to the edge between the park and residential neighborhoods than expected by chance, and (2) that pairs nesting near edges produced the largest and most offspring. However, fates were reversed …

Long-Term Nitrogen Addition Decreases Carbon Leaching In A Nitrogen-Rich Forest Ecosystem, X. Lu, Frank S. Gilliam, G. Yu, H. Chen, J. Mo

Biological Sciences Faculty Research

Dissolved organic carbon (DOC) plays a critical role in the carbon (C) cycle of forest soils, and has been recently connected with global increases in nitrogen (N) deposition. Most studies on effects of elevated N deposition on DOC have been carried out in N-limited temperate regions, with far fewer data available from N-rich ecosystems, especially in the context of chronically elevated N deposition. Furthermore, mechanisms for excess N-induced changes of DOC dynamics have been suggested to be different between the two kinds of ecosystems, because of the different ecosystem N status. The purpose of this study was to experimentally examine …

Estudios Científicos En El Estado De Hidalgo Y Zonas Aledañas, Volumen Ii, Griselda Pulido-Flores, Scott Monks

Zea E-Books Collection

Los 16 capítulos que conforman este libro son una contribución al conocimiento de la biodiversidad y conservación de los recursos naturales en el estado de Hidalgo, México.

Se aborda el derecho de propiedad intelectual en la biodiversidad, citando algunos ejemplos de México. Así mismo, se presenta un estudio de la biodiversidad y distribución de la herpetofauna en cuatro tipos de vegetación. Desde el punto de vista de la helmintología se presentan dos estudios de los helmintos parásitos de vertebrados silvestres; con nuevos registros de hospederos y localidades de algunas especies de helmintos para Hidalgo. También, se aborda el uso de …

The Effects Of Fire On The Vernal Herbs Of An Eastern Mesic Forest, David Randolph Kem

Masters Theses & Specialist Projects

The effects of fire on vernal herbs of the mesic forests of eastern North America are poorly understood. I studied the influence of prescribed fire on species richness, abundance of rare and common species, and density of exotics in the vernal herbaceous layer. To determine these effects, three sites in central Kentucky were surveyed prior to and following one of three treatments: spring burn, winter burn, or negative control. I conducted low-intensity spring burns in April 2010 and winter burns in February 2011. I used chi square analyses to test for changes in species richness, abundance of rare species, abundance …

Characterization Of Whole Pine Tree Substrates For Adventitious Rooting Of Cuttings And Initial Growth Of Seedlings, Anthony Lynn Witcher

Dissertations

Processed whole pine (Pinus taeda L.) trees have been extensively evaluated to supplement peatmoss and pine bark usage in container substrates for greenhouse and nursery crop production. The suitability of whole pine tree (WPT) substrates for crop propagation has not been investigated. Demonstrating the versatility of WPT substrates is essential to expanding their commercial availability and use.

The objective of this work was to evaluate WPT substrates for stem cutting and seed propagation of ornamental crops, and to identify factors affecting root development. Stem cutting and seedling root development was evaluated in WPT and traditional (peatmoss and pine bark) …

Interactive Effects Of Nitrogen And Phosphorus On Soil Microbial Communities In A Tropical Forest, Lei Liu, Tao Zhang, Frank S. Gilliam, Per Gundersen, Wei Zhang, Hao Chen, Jiangming Mo

Biological Sciences Faculty Research

Elevated nitrogen (N) deposition in humid tropical regions may exacerbate phosphorus (P) deficiency in forests on highly weathered soils. However, it is not clear how P availability affects soil microbes and soil carbon (C), or how P processes interact with N deposition in tropical forests. We examined the effects of N and P additions on soil microbes and soil C pools in a N-saturated old-growth tropical forest in southern China to test the hypotheses that (1) N and P addition will have opposing effects on soil microbial biomass and activity, (2) N and P addition will alter the composition of …

Estimated Losses Of Plant Biodiversity Across The U.S. From Historical N Deposition From 1985—2010., Christopher M. Clark, Philip E. Morefield, Frank S. Gilliam, Linda H. Pardo

Biological Sciences Faculty Research

Although nitrogen (N) deposition is a significant threat to herbaceous plant biodiversity worldwide, it is not a new stressor for many developed regions. Only recently has it become possible to estimate historical impacts nationally for the United States. We used 26 years (1985–2010) of deposition data, with ecosystem-specific functional responses from local field experiments and a national critical loads (CL) database, to generate scenario-based estimates of herbaceous species loss. Here we show that, in scenarios using the low end of the CL range, N deposition exceeded critical loads over 0.38, 6.5, 13.1, 88.6, and 222.1 million ha for the Mediterranean …