Forest Sciences Commons^™

The Motion Of Trees In The Wind: A Data Synthesis, Toby D. Jackson, Sarab Sethi, Ebba Dellwik, Nikolas Angelou, Amanda Bunce, Tim Van Emmerik, Marine Duperat, Jean-Claude Ruel, Axel Wellpott, Skip Van Bloem

Publications

Interactions between wind and trees control energy exchanges between the atmosphere and forest canopies. This energy exchange can lead to the widespread damage of trees, and wind is a key disturbance agent in many of the world's forests. However, most research on this topic has focused on conifer plantations, where risk management is economically important, rather than broadleaf forests, which dominate the forest carbon cycle. This study brings together tree motion time-series data to systematically evaluate the factors influencing tree responses to wind loading, including data from both broadleaf and coniferous trees in forests and open environments.

We found that …

Stem-Inhabiting Fungal Communities Differ Between Intact And Snapped Trees After Hurricane Maria In A Puerto Rican Tropical Dry Forest, François Maillard, Erin Andrews, Molly Moran, Peter G. Kennedy, Skip Van Bloem, Jonathan S. Schilling

Publications

Hurricanes impact forests by damaging trees and altering multiple ecosystem functions. As such, predicting which individuals are likely to be most affected has crucial economic importance as well as conservation value. Tree stem-inhabiting fungal communities, notably rot-causing agents, have been mentioned as a potential factor of tree predisposition to hurricane damage, but this assumption remains poorly explored. To examine this relationship, we sampled the stem wood of intact and damaged trees shortly after Hurricane Maria in a Puerto Rican dry tropical forest in 2017. We categorized samples depending on two types: trees with intact stems and trees in which stems …

An Analysis Of Common Forest Management Practices For Carbon Sequestration In South Carolina, Lucas Clay, Marzieh Motallebi, Bo Song

Publications

South Carolina (SC) has a variety of different forest types, and they all have potential to sequester a certain amount of carbon. Private forest landowners control a significant portion of the overall forestland in SC, and their management efforts can maintain or improve forest carbon stocks. Currently, the second largest carbon market in the world is the California Carbon Market, which gives a monetary value to sequestered carbon. One carbon credit is equal to one metric ton of carbon and is currently worth around $15.00. Forest management plans are geared toward increasing carbon sequestration over time. This study aims to …

Seed Rain Along A Gradient Of Degradation In Caribbean Dry Forest: Effects Of Dispersal Limitation On The Trajectory Of Forest Recovery, Brett T. Wolfe, Raúl Macchiavelli, Skip Van Bloem

Publications

Questions

Tropical dry forests that experience severe disturbances (e.g., fires) often remain degraded for long time periods, during which non-native grasses and trees dominate. One barrier to native tree regeneration in degraded areas may be seed dispersal limitation. To better understand how dispersal limitation influences recovery from degradation, we tested whether the mode and rates of seed dispersal differed in degraded sites dominated either by the exotic tree Leucaena leucocephala or open areas dominated by introduced pasture grasses. We also tested whether L. leucocephala stands facilitate the recruitment of native trees by increasing their seed input compared to open grass …

Evaluating Myopic Loss Aversion Of Forestland Owners, Mustapha Alhassan, Marzieh Motallebi

Publications

Attracting forestland owners to participate in carbon markets can be challenging for several reasons including offset price volatility, legislative uncertainties, high costs of offset project development, long contract lengths, and landowners’ risk preferences. In this article, we elicit risk preferences and investigate Myopic Loss Aversion (MLA) of forestland owners using an economic experiment. The economic experiment is a betting game and we find that forestland owners exhibit MLA because they bet higher when returns from their investments are evaluated less frequently. Our results provide valuable information for developing carbon market protocols, especially in setting optimal evaluation periods of forest carbon …

Key Habitat Features Facilitate The Presence Of Barred Owls In Developed Landscapes, Marion A. Clement, Kyle Barrett, Robert F. Baldwin

Publications

As urbanization continues to transform landscapes, it is imperative to find ways to conserve biodiversity within fragmented habitats. Forest interior dwelling birds are particularly vulnerable to development pressures because they require large tracts of forest to support their life cycles. Although Barred Owls (Strix varia) are frequently described as an obligate mature forest species, they have been found in urbanized landscapes. To determine if certain habitat characteristics, such as mature trees, facilitate the presence of Barred Owls in developed regions, we modeled Barred Owl occupancy probability along a development gradient in the Piedmont region of the southeastern United …

Variation In Regional And Landscape Effects On Occupancy Of Temperate Bats In The Southeastern U.S., Benjamin D. Neece, Susan C. Loeb, David S. Jachowski

Publications

Habitat loss, wind energy development, and the disease white-nose syndrome are major threats contributing to declines in bat populations in North America. In the southeastern US in particular, the recent arrival of white-nose syndrome and changes in landscape composition and configuration have driven shifts in bat species populations and distributions. Effective management strategies which address these large-scale, community-level threats require landscape-scale analyses. Our objective was to model the relationship between ecoregional and landscape factors and occupancy by all bat species in South Carolina, USA, during summer. We conducted acoustic surveys from mid-May through July 2015 and 2016 and evaluated temporally …

Accounting For Soil Inorganic Carbon In The Ecosystem Services Framework For United Nations Sustainable Development Goals, Garth Raymond Groshans

All Theses

Soil inorganic carbon (SIC) is currently not included in the list of key soil properties related to ecosystem services (e.g., provisioning, regulating, cultural, and supporting services). Soil inorganic carbon is a dynamic key soil property used in soil classification, taxonomy and fertility, therefore its inclusion in the framework of ecosystem services is important. With soils rapidly changing due to human use and climate change, the soil ecosystem services framework should not include only soil organic carbon (SOC), but SIC as well since it is of global importance to soil fertility and the long-term carbon cycle, especially in semiarid and arid …

Spread Of Common Native And Invasive Grasses And Ruderal Trees Following Anthropogenic Disturbances In A Tropical Dry Forest, Xavier A. Jaime, Skip J. Van Bloem, Frank H. Koch, Stacy A.C. Nelson

Publications

Introduction

A fundamental challenge to the integrity of tropical dry forest ecosystems is the invasion of non-native grass species. These grasses compete for resources and fuel anthropogenic wildfires. In 2012, a bulldozer from the Puerto Rico Electric Power Authority cleared a 570-m trail from a state road into a mature dry forest section of Guánica Forest to control a wildfire. We monitored colonization by a non-native invasive grass (Megathyrsus maximus), a highly invasive tree (Leucaena leucocephala), and a native grass (Uniola virgata), as well as natural regeneration, along the bulldozer trail. We determined whether …

Effects Of Salinity And Wet–Dry Treatments On C And N Dynamics In Coastal-Forested Wetland Soils: Implications Of Sea Level Rise, Xijun Liu, Alexander Ruecker, Bo Song, William H. Conner, Alex T. Chow

Publications

Forested wetlands dominated by baldcypress (Taxodium distichum) and water tupelo (Nyssa aquatica) are commonly found in coastal regions of the southeastern United States. Global climate change and in particular sea level rise will alter the frequency and magnitude of wet/dry periods and salinity levels in these ecosystems. Soil microcosm experiments were set up to identify the effects of water level variations (0.4–3.0 g-water g-soil−1) and salinity changes (0, 1 and 5 ppt of NaCl) on greenhouse gas emissions (CH4, CO2, and N2O) and dissolved organic carbon (DOC) characteristics from forested wetland soils. Our results indicate that, the effect …

Assessing Alternative Silvicultural Prescriptions For Mid-Rotation, Unthinned, Spruce-Fir Stands In Maine, Patrick Hiesl, Mindy S. Crandall, Aaron R. Weiskittel, Anil R. Kizha

Publications

Determining the optimal timing and type of entry in mid-rotation, unthinned stands can be complicated by a variety of economic and biological factors. In this analysis, long-term data from the Commercial Thinning Research Network was used to project spruce-fir (Picea spp.—Abies balsamea (L.) Mill.) stand growth on six different sites across Maine following six alternative thinning treatments (33% and 50% relative density removal paired with low, crown, and dominant thinning methods). Results showed that the low-thinning treatment performed best in terms of maximum net present value, stand age at time of maximum net present value, and average merchantable …

In-Stream Habitat Predicts Salamander Occupancy And Abundance Better Than Landscape-Scale Factors Within Exurban Watersheds In A Global Diversity Hotspot, Nathaniel Weaver, Kyle Barrett

Publications

The southern Appalachian Mountains have experienced rapid human population growth rates since the 1980s. Land used practices are shifting from rural to residential. The majority of development has been low density, and is often near biologically diverse areas such as National Forests and National Parks. The long-term effects of urbanization in the southeastern Appalachian Mountains are not clearly understood and even less is known with respect to stream salamander response to urbanization. In order to determine the temporal influence of exurban housing on southern Appalachian streams we sampled 27 first- and second-order streams in watersheds containing exurban developments ranging in …

The Influence Of Exurban Landscapes And Local Site Characteristics On Riparian Vegetation, Nathan Weaver, Kyle Barrett, Don L. Hagan

Publications

The southern Appalachian Mountains have experienced large population growth and a change in land use in the past 30 years. The majority of development has been low density, suburban land, known as exurban development. The long-term effects of exurbanization on riparian vegetative communities in the southeastern Appalachian Mountains are not well known. We sought to determine if vegetative community composition and structure change as a function of watershed–level variables such as time since neighborhood development or percent impervious surface within the watershed. We also assessed local–scale measures of disturbance such as canopy cover and basal area. Over two years we …

Forest Composition And Growth In A Freshwater Forested Wetland Community Across A Salinity Gradient In South Carolina, Usa, Xijun Liu, William Conner, Bo Song, Anand D. Jayakaran

Publications

Tidal freshwater forested wetlands (TFFW) of the southeastern United States are experiencing increased saltwater intrusion mainly due to sea-level rise. Inter-annual and intra-annual variability in forest productivity along a salinity gradient was studied on established sites. Aboveground net primary productivity (ANPP) of trees was monitored from 2013 to 2015 on three sites within a baldcypress (Taxodium distichum) swamp forest ecosystem in Strawberry Swamp on Hobcaw Barony, Georgetown County, South Carolina. Paired plots (20 × 25-m) were established along a water salinity gradient (0.8, 2.6, 4.6 PSU). Salinity was continuously monitored, litterfall was measured monthly, and growth of overstory …

Poor Transferability Of A Distribution Model For A Widespread Coastal Marsh Bird In The Southeastern United States, Nicolette S. Roach, Elizabeth A. Hunter, Nathan P. Nibbelink, Kyle Barrett

Publications

Species distribution models have been applied across a wide range of spatial scales to generate information for conservation planning. Understanding how well models transfer through space and time is important to promote effective species–habitat conservation. Here, we assess model transferability in coastal tidal marshes of the southeastern United States using count data of a widespread marsh bird: the Clapper Rail (Rallus crepitans). We developed species–habitat models at a state level in both South Carolina and Georgia, and then assessed how well top models from each state predicted abundance in the other state. Internally (locally) validated models performed well …

Shifts In Biomass And Productivity For A Subtropical Dry Forest In Response To Simulated Elevated Hurricane Disturbances, Jennifer A. Holm, Skip J. Van Bloem, Guy R. Larocque, Herman H. Shugart

Publications

Caribbean tropical forests are subject to hurricane disturbances of great variability. In addition to natural storm incongruity, climate change can alter storm formation, duration, frequency, and intensity. This model-based investigation assessed the impacts of multiple storms of different intensities and occurrence frequencies on the long-term dynamics of subtropical dry forests in Puerto Rico. Using the previously validated individual-based gap model ZELIG-TROP, we developed a new hurricane damage routine and parameterized it with site- and species-specific hurricane effects. A baseline case with the reconstructed historical hurricane regime represented the control condition. Ten treatment cases, reflecting plausible shifts in hurricane regimes, manipulated …

Will Seasonally Dry Tropical Forests Be Sensitive Or Resistant To Future Changes In Rainfall Regimes?, Kara Allen, Juan Manuel Dupuy, Maria G. Gei, Catherine Hulshof, David Medvigy, Camila Pizano, Christina M. Smith, Annette Trierweiler, Skip J. Van Bloem, Bonnie G. Waring, Xiangtao Xu, Jennifer S. Powers

Publications

Seasonally dry tropical forests (SDTF) are located in regions with alternating wet and dry seasons, with dry seasons that last several months or more. By the end of the 21st century, climate models predict substantial changes in rainfall regimes across these regions, but little is known about how individuals, species, and communities in SDTF will cope with the hotter, drier conditions predicted by climate models. In this review, we explore different rainfall scenarios that may result in ecological drought in SDTF through the lens of two alternative hypotheses: 1) these forests will be sensitive to drought because they are already …

Chinese Tallow Invasion In Maritime Forests: Understand Invasion Mechanism And Develop Ecologically-Based Management, Lauren Susan Pile

All Dissertations

Invasion by highly aggressive, non-native, invasive plants is a significant threat to management and conservation priorities as these plants can transform ecosystem functions and processes. In this study, I investigated the non-native, invasive tree, Chinese tallow (Triadica sebifera (L.) Small) in the maritime forests of Parris Island, South Carolina. I studied the role of land-use history and modern forest disturbance in facilitating the invasion of Chinese tallow. I found that stands previously cleared for agriculture and reforested with slash pine (Pinus elliottii Englem.) since the 1970s had significantly more Chinese tallow stems than stands that remained forested since …

Adaptation Of Soil Judging To Northeast China, He Yun

All Theses

Soil Judging teaches students important skills for field identification of soil types, properties, and interpretations for use. The adaptation of Soil Judging in Northeast China can be beneficial to students as well as government agencies and the private sector. The objective of this study was to adapt Soil Judging to the Northeast region of China by a graduate student from China, who was trained using an undergraduate course in Soil Judging and a regional Soil Judging competition. Unlike the U.S., China has 14 soil orders, with six soil orders somewhat similar to the ones found in the Southeast region of …

Post-Hurricane Fuel Dynamics And Forest Regeneration Of Coastal Pine Stands In Southeast United States, Shanyue Guan

All Theses

Hurricanes have long been powerful and recurring disturbances in many coastal forest ecosystems. Intense hurricanes often produce a large amount of dead fuels within their affected forests, but how post-hurricane fuel complex changes with time, due to decomposition and management such as salvage, and the fire behavior affected by the changed fuel load remains largely unknown. To better understand the fuel and regeneration dynamics, field measurement and modeling were conducted within undamaged stands and hurricane damaged stands, including salvaged and unsalvaged stands in southern pine forests impacted by hurricane Hugo (1989), Opal (1995), Katrina (2005), and Ike (2008). We found …

Ecohydrological Function Of Lower Coastal Plain Bioretention Cells In South Carolina, Jessica Palazzolo

All Theses

Flooding and stormwater control is a critical issue in coastal South Carolina because of shallow water table elevation, topography and rapid urbanization in the region. A best management practice (BMP) using low impact design (LID) principles known as a bioretention cell (BRC) is gaining popularity for stormwater management. Five BRCs in four landscape positions (well-drained uplands, tidal-proximal, poorly-drained-uplands, and floodplain) were instrumented for microclimate, soil moisture, and water table elevation for hydraulic efficiency and for water quality measurements. Three BRCs did not have an overflow outlets, one BRC (floodplain) employed an underdrain system, and one BRC (tidal proximal) had an …

Growth Responses Of Genetically Improved Open Pollenated, Full-Sibling, And Clonal Loblolly Pine To The FlexstandTm Silvicultural System, Patrick Ma

All Theses

ABSTRACT Loblolly pine (Pinus taeda) is often listed as the most commercially important timber species in the southeastern United States and is subject to genetic improvement via breeding programs to increase sawtimber yield, stem quality, and disease resistance. ArborGen has trademarked the FlexStand^TM Silvicultural System (a method of interplanting rows of genetically improved trees with less expensive biomass trees) as a more economical solution to growing Loblolly pine. Two studies were conducted to in order to assess the FlexStand^TM Silvicultural System. The first study assessed seedling mortality and growth of four different genetic combinations were assessed in the …

Use Of Unmanned Aerial Vehicles (Uav) For Urban Tree Inventories, Brian Ritter

All Theses

In contrast to standard aerial imagery, unmanned aerial systems (UAS) utilize recent technological advances to provide an affordable alternative for imagery acquisition. Increased value can be realized through clarity and detail providing higher resolution (2-5 cm) over traditional products. Many natural resource disciplines such as urban forestry will benefit from UAS. Tree inventories for risk assessment, biodiversity, planning, and design can be efficiently achieved with the UAS. Recent advances in photogrammetric processing have proved automated methods for three dimensional rendering of aerial imagery. Point clouds can be generated from images providing additional benefits. Association of spatial locational information within the …

Socioeconomic Indicators Of Family Forest Owner Use Of Federal Income Tax Provisions, John Hatcher

All Dissertations

Family forest owners control a majority of the South's forest land and nearly half of its growing stock. These owners are a diverse group with widely varied objectives for ownership and management. Many family forest owners manage their holdings for timber production objectives and thus, are concerned with issues such as reforestation incentives and tax treatment of timber revenues. Their actual knowledge of the tax aspects of timber management varies, with some owners unaware of the federal income tax provisions that apply to timber. This study uses econometric techniques to establish socioeconomic predictors of family forest owner use of seven …

Water For Electricity In The Upper Savannah Basin: Impacts On Freshwater Mussels, Alan Johnson, Snehal Mhatre

Graduate Research and Discovery Symposium (GRADS)

The water resources of the Upper Savannah River Basin are subjected to extensive water withdrawals for production of electricity for the region. The use of Savannah River Basin water resources for electricity production and the associated impact on reservoir levels, streamflows, and thermal regimes is in conflict with the requirements of in-stream biota particularly freshwater mussels. The Savannah River Basin contains atleast 26 unionid species, most of which are listed as endangered, threatened, or of special concern at the state level. Populations of these species have experienced significant declines and extirpations in the recent decades. Of these unionid species, brook …

Fire Resistance In A Caribbean Dry Forest: Inferences From The Allometry Of Bark Thickness, Brett T. Wolfe, Gabriel E. Saldaña Diaz, Skip J. Van Bloem

Publications

Trees’ resistance to fire-induced mortality increases with bark thickness, which varies widely among species and generally increases with stem diameter. Because dry forests are more fire-prone than wetter forests, bark may be thicker in these forests. However, where disturbances such as hurricanes suppress stem diameter, trees may not obtain fire-resistant bark thickness. In two hurricane-prone Caribbean dry-forest types in Puerto Rico—deciduous forest and scrub forest—we measured bark thickness on 472 stems of 25 species to test whether tree species obtain bark thicknesses that confer fire resistance, whether bark is thicker in the fire-prone scrub forest than in the deciduous forest, …

An Analysis Of Arthropod Interceptions By Aphis-Ppq And Customs And Border Protection In Puerto Rico, David A. Jenkins, Russell F. Mizell, Skip Van Bloem, Stefanie Whitmire, Leyinska Wiscovitch, Crystal Zaleski, Ricardo Goenaga

Publications

USDA Animal Plant Health Inspection Service Plant Protection and Quarantine (APHIS-PPQ) and Customs and Border Protection (CBP) inspect traffic entering the United States for arthropods posing a threat to national agriculture or ecosystems. We analyzed interceptions made by these agencies in Puerto Rico and the U.S. Virgin Islands between October 2006 and December 2009 for patterns with regard to the frequency of interceptions, origins of interceptions, and the taxa intercepted. 6,952 arthropods were intercepted in freight or luggage entering Puerto Rico and the U.S. Virgin Islands from foreign countries and 9,840 arthropods were intercepted from freight or luggage leaving Puerto …

Comparing Mechanical Mastication, Herbicide Application, And Prescribed Fire Within An Established Longleaf Pine (Pinus Palustris Mill.) Ecosystem, Brett Moule

All Dissertations

Longleaf pine (Pinus palustris Mill.) forests once dominated the landscape throughout the Southeast and much of its success could be attributed to ecological disturbances such as fire. However, the use of fire as a management tool may be at risk due to a growing human population, negative impacts resulting from smoke production, and the imposition of restrictive federal and state laws, policies, and standards. This study was designed to determine whether alternative silviculture treatments such as herbicide or mechanical mastication can be used as surrogates to prescribed fire. We applied three commonly used silviculture treatments (prescribed burning, mechanical mastication, …

Temporal Analysis Of Field, Ssurgo, And Lidar Derived Site Indices In The Southeastern U.S., Steven Ham

All Theses

Sustainable forest management requires accurate information about site index (SI, tree height at a base age). The objectives of this study were to compare site indices from field inventory data (2008-2009), Soil Survey Geographic Database (SSURGO), and Light Detection and Ranging (LiDAR, 2008), and to determine the uncertainty in the site indices from the southern part of the Clemson Experimental Forest. When LiDAR derived analysis were used to compare to SSURGO there were statistical differences for site indices for all of the tree species in this study: loblolly pine (Pinus taeda), scarlet oak (Quercus coccinea), shortleaf pine (Pinus echinata), white …

Forest Fragments As Barriers To Fruit Fly Dispersal: Anastrepha (Diptera: Tephritidae) Populations In Orchards And Adjacent Forest Fragments In Puerto Rico, David A. Jenkins, Paul E. Kendra, Skip Van Bloem, Stefanie Whitmire, Russ Mizell Iii, Ricardo Goenaga

Publications

McPhail-type traps baited with ammonium acetate and putrescine were used to monitor populations of Anastrepha obliqua (Macquart) and Anastrepha suspensa(Loew) in two orchards with hosts of these flies (mango, Mangifera indica L., and carambola, Averrhoa carambola L.), as well as in forest fragments bordering these orchards. Contour maps were constructed to measure population distributions in and around orchards. Our results indicate that Anastrephapopulations are focused around host fruit in both space and time, that traps do not draw fruit flies away from hosts, even when placed within 15 m of the host, and that lures continue to function …