Measuring Building Height Using Point Cloud Data Derived From Unmanned Aerial System Imagery In An Undergraduate Geospatial Science Course, David L. Kulhavy, I-Kuai Hung, Daniel R. Unger, Reid Viegut, Yanli Zhang

Faculty Publications

The use of Unmanned Aerial Systems (UAS), also known as drones is increasing in geospatial science curricula within the United States. Within the Arthur Temple College of Forestry and Agriculture (ATCOFA) at Stephen F. Austin State University, Texas, seniors in the geospatial science program complete capstone projects to evaluate current geospatial technology to investigate complex ecological, social and environmental issues. Under the umbrella of a student initiated and designed senior project, students designed a study to estimate height of buildings with UAS data incorporating UAS data, LP360 and ArcScene programs, and Pictometry web-based interface. Results from a statistical analysis of …

Use Of Altmetrics To Analyze Scholarworks In Natural Resource Management, David L. Kulhavy, R Philip Reynolds, Daniel R. Unger, Matthew W. Mcbroom, I-Kuai Hung, Yanli Zhang

Faculty Publications

Digital preservation of library materials has increased the need for methods to access the documents and contents maintained in digital archives. The use of altmetrics to quantify the impact of scholarly works, including PlumX, is increasing readership by listing articles in reference services. The outreach from the digital repository ScholarWorks at Stephen F. Austin State University (SFASU) highlights the impact within the natural resources community from Digital Commons, Forest Sciences Commons; and from the Natural Products Chemistry and Pharmacognosy Commons. The use of PlumX altmetrics was examined to evaluate usage, impact, and digital audience downloads for the Arthur Temple College …

Reconstruction Of Piñon–Juniper Woodlands In The Sky Islands Of The Davis Mountains, Texas, Usa, Mohammad Bataineh, Brian P. Oswald, Hans M. Williams, Dan Unger, I-Kuai Hung

Faculty Publications

Piñon (Pinus spp. L.)–juniper (Juniperus spp. L.) woodlands’ historical stand structures were recreated to provide reference conditions and document long‐term changes in the Sky Islands of the Davis Mountains, Texas. Restoration of these isolated woodlands requires insights into the range of variability in current and historical stand structures, as well as an understanding of the spatiotemporal establishment and recruitment patterns of tree species. With drastic changes in forests and woodlands of the Southwestern United States widely reported, the main objective of this study was to reconstruct woodland tree temporal and spatial establishment patterns. A stratified random sampling approach was used …

Initial Establishment Success Of Five Forages In An East Texas Loblolly Pine (Pinus Taeda) Silvopasture, Michael Richard, Ken Farrish, Brian P. Oswald, Hans M. Williams, Michael Maurer

Faculty Publications

The establishment at the end of 1 year of five forages was evaluated in a loblolly pine (Pinus taeda L.) silvopasture system. The five forages were: ‘Pensacola” bahiagrass (Paspalum notatum Fluegge), “Texas Tough” bermudagrass (Cynodon dactylon L. Pers.), “Alamo” switchgrass (Panicum virgatum L.), “San Marcos” Eastern gamagrass (Tripsacum dactyloides L.), and a native mix containing 45% “Texas” little bluestem (Schizachyrium scoparium Michx Nash), 15% sand lovegrass (Eragrostis trichodes Nutt. L. Alph. Wood), 15% “Blackwell” switchgrass (Panicum virgatum L.), 10% “Lometa” indiangrass (Sorgastrum nutans L. Nash), 10% “Haskell” sideoats grama (Bouteloua …

The Influence Of Environmental Variables On The Height Growth Of Loblolly Pine (Pinus Taeda) In The Western Gulf, Osakpamwan Edo-Iyasere

Electronic Theses and Dissertations

Understanding the effects of environmental factors on stand growth is important in optimizing forest management plans. This study investigated the effects of soil and climate factors on the height growth (site index) of loblolly pine (Pinus Taeda L.) using data collected from permanent plots established in intensively-managed plantations across East Texas and Western Louisiana. The Chapman-Richards model was selected as the base model to describe the height-age relationships and important soil and climate variables were incorporated into the models as model parameter coefficient adjustors. Our results showed that the most important factors for predicting site index were nitrogen …

Preliminary Flammability Assessment Of Sea Buckthorn From The Netherlands Compared To Known Flammable Shrubs Of The Southern And Western Us, Michael Tiller, Brian P. Oswald, Mathijs Schuijn

Faculty Presentations

Sea buckthorn (Hippophae rhamnoides) is a common coastal species in The Netherlands that potentially burns with extreme energy levels. In this region of Europe that is experiencing increases in wildfire events, the need to gain a greater understanding of energy released when this species burns will improve fire behavior predictions. The objective of this study was to conduct an initial investigation into the foliage flammability of sea buckthorn to a common southern United States native shrub known for its flammability, yaupon (Ilex vomitoria), and two common dominant shrub species in California chaparral, chamise (Adenostoma fasciculatum …

Initial Investigation Of Seasonal Flammability Of Three Invasive East Texas Forest Understory Fuels Using Thermogravimetric Analysis, Mike Tiller, Brian P. Oswald, Alyx Frantzen, Warren Conway, Ikuai Hung

Faculty Publications

East Texas forest understory fuels have become increasingly infested with invasive species which have contributed to greater hazardous fuel loads when combined with decades of fire exclusion and passive management. This study focused on estimating seasonal changes in flammability parameters of invasive yaupon (Ilex vomitoria), Chinese privet (Ligustrum sinense), and Chinese tallow (Triadica sebifera) using thermogravimetric analysis. Foliage and stem samples were collected in the dormant (February) and growing (August) seasons. Differential thermogravimetric (DTG) and proximate analyses were used to estimate species specific flammability parameters related to relative spontaneous ignition temperature (RSIT), gas-phase maximum …

Initial Investigation Of Seasonal Flammability Of Three Invasive East Texas Forest Understory Fuels Using Thermogravimetric Analysis, Michael Tiller, Brian P. Oswald, Alyx Frantzen, Warren Conway, I-Kuai Hung

Faculty Presentations

East Texas forest understory fuels have become increasingly infested with invasive species which have contributed to greater hazardous fuel loads when combined with decades of fire exclusion and passive management. This study focused on estimating seasonal changes in flammability parameters of invasive yaupon (Ilex vomitoria), Chinese privet (Ligustrum sinense), and Chinese tallow (Triadica sebifera) using thermogravimetric analysis. Foliage and stem samples were collected in the dormant (February) and growing (August) seasons. Differential thermogravimetric (DTG) and proximate analyses were used to estimate species specific flammability parameters related to relative spontaneous ignition temperature (RSIT), gas-phase maximum …

Simulated Mine Land Reclamation Impact On Biomass Partitioning And Nutrient Contents In Loblolly Pine, Osarumen Egharevba

Electronic Theses and Dissertations

Forest productivity on reclaimed mine land is hindered by soil compaction. Different techniques have been used to alleviate the effect of compaction to various degrees of success. The Forestry Reclamation Approach (FRA) was developed in the Appalachians and has been used to improve forest productivity on reclaimed mines in this region. The FRA provides a step by step method designed to reduce compaction, control erosion, provide land stabilization and accelerate forest succession. This method had not been evaluated in the Gulf Coastal Plain, where the pan scraper reclamation method is commonly used. However, using pan scrapers increases mine soil compaction …

Does Installation Method Affect Snake Entanglement In Erosion Control Blankets?, Nicholas C. Schiwitz, Kasey L. Jobe, Krista J. Ward

Undergraduate Research Conference

Erosion control blankets (ECBs) are installed at construction sites to mitigate against soil loss and promote plant growth. Wildlife, particularly snakes, are prone to becoming entangled in ECBs that contain fixed‐intersection, small‐diameter polypropylene mesh with multiple layers (Ebert et al. 2019 Wildl. Soc. Bull.; Fig. 1).

The majority of ECBs on the Texas Department of Transportation’s Approved Product List contain fixed-intersection mesh, which pose a risk to snakes.

Snake entanglements often occur at the edge of an ECB where the snake often passes between the multiple mesh layers (Ebert et al. 2019 Wildl. Soc. Bull.)

Burying the edge of an …

On The Diversity Of Erosion Control Products: Implications For Snake Entanglement, Kasey L. Jobe, Nicholas C. Schiwitz, Krista Ward

Undergraduate Research Conference

After a road construction project, Texas Department of Transportation (TxDOT) mandates that erosion control products (ECPs) are installed to prevent soil loss and promote plant growth. However, their presence on the landscape pose negative consequences to wildlife via entanglement.

TxDOT provides an Approved Products List (APL) of ECPs meeting soil erosion prevention and plant growth standards. In Texas, multiple types of ECPs are produced with a range of materials and attributes to decrease the erosion potential on multiple soil types and slopes. Certain attributes are more likely to lead to snake entanglement (Ebert et al. 2019 Wildl. Soc. Bull.; Fig. …

Mediterranean House Geckos Exploit Novel Resources In A Recipient Lizard Assemblage, John M. Arnett, Connor S. Adams, Carmen G. Montana

Undergraduate Research Conference

A species’ ecological niche represents the environmental conditions needed for an individual to replace itself and is comprised of multiple resource axes (Pianka 2000 Evol. Ecol.).

One mechanism of establishment of non-native species is via exploitation of novel resources in recipient ecosystems through their unique functional traits (Schalk et al. 2018 Biol. Invas.).

Mediterranean House Geckos (Hemidactylus turcicus) are an exotic species introduced in urban areas across Texas, yet little is known about their resource use relative to native lizards.

We hypothesized that H. turcicus would exhibit low overlap in resource use in their habitat, dietary, and isotopic niches compared …

The Effect Of Sodium Chloride On Hybrid Taxodium Selections, Anna Koonce, Edward Bush, David Creech

Faculty Publications

Saltwater intrusion is a major cause of coastal erosion. New hybrid bald cypress species have been shown to exhibit salinity tolerance compared to native bald cypress species. Planting these hybrids, or Nanjing Bot Garden genotype (NBG), trees where their roots can stabilize soil and preserve land may reduce coastal erosion in areas subjected to saltwater intrusion. The purpose of this experiment was to determine whether or not selected bald cypress NBG genotype tree species survive better than native bald cypress trees in areas inundated with saline water. Leaves were harvested, dried and analyzed for their elemental concentration. NBG genotype trees …

Comparing Canopy Metric Estimations Using Three Conifer Species In The Netherlands, Alan Duncan Hibler, Brian P. Oswald, Nienke Brouwer, Ester Willemsen, Hans M. Williams

Faculty Publications

A growing concern associated with fire in The Netherlands is estimating the spread of wildfire, however often the data needed to estimate canopy fires are lacking. The primary parameter required is canopy bulk density (CBD), which requires estimations of canopy gap fraction and leaf area index (LAI). The accuracy of three indirect methods of estimating CBD (a densiometer, hemispherical canopy photographs (HCP), and a LI-COR LAI 2200c plant canopy analyzer) was compared for three common tree species in the Netherlands [Scots pine (Pinus sylvestris L.), black pine (Pinus nigra Arnold) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco)]. No …

An Integrated Method For Coding Trees, Measuring Tree Diameter, And Estimating Tree Positions, Linhao Sun, Luming Fang, Yuhi Weng, Siqing Zheng

Faculty Publications

Accurately measuring tree diameter at breast height (DBH) and estimating tree positions in a sample plot are important in tree mensuration. The main aims of this paper include (1) developing a new, integrated device that can identify trees using the quick response (QR) code technique to record tree identifications, measure DBH, and estimate tree positions concurrently; (2) designing an innovative algorithm to measure DBH using only two angle sensors, which is simple and can reduce the impact of eccentric stems on DBH measures; and (3) designing an algorithm to estimate the position of the tree by combining ultra-wide band (UWB) …

Activity Level-Predation Risk Tradeoff In A Tadpole Guild: Implications For Community Organization Along The Hydroperiod Gradient, Nicholas C. Schiwitz, Christopher M. Schalk, Daniel Saenz

Faculty Publications

Increasing activity levels permit greater food intake for use towards growth and reproduction, consequently increasing predation risk via increased detection. Larval anurans are models to examine activity level-predation risk tradeoffs, as they occupy a variety of lentic habitats that impose constraints on the distribution and abundance of species. Ephemeral ponds have a low abundance and diversity of predators and as a result tadpole species tend to have high foraging rates for rapid development. Permanent ponds generally possess a greater diversity and abundance of predators and tadpoles inhabiting these locations tend to have low activity rates or chemical defenses to minimize …

Modeling Early Responses Of Loblolly Pine Growth To Thinning In The Western Gulf Coastal Plain Region, Yuhi Weng, J. Grogan, Dean W. Coble

Faculty Publications

Growth response to thinning has long been a research topic of interest in forest science. This study presents the first 3–4 years of response of loblolly pine (Pinus taeda L.) growth to thinning at different intensities. Data were collected from the East Texas Pine Research Project’s region-wide loblolly pine thinning study, which covers a wide variety of stand conditions. Four treatments, light, moderate, and heavy thinning, respectively having 370, 555, and 740 residual trees per hectare after thinning, and an unthinned control, were included. Individual tree diameter at breast height (dbh) and total height were recorded annually for the …

Integration Of Citygreen Landscape Ecological Analysis Into A Capstone Environmental Science Course, David L. Kulhavy, Daniel R. Unger, Reid Viegut, I-Kuai Hung, Yanli Zhang

Faculty Publications

CITYgreen Geographic Information Systems software was used to develop a campus wide cover type map for Stephen F. Austin State University in an environmental science landscape ecology course. The finding indicated an equal division of forest cover type compared to impervious surface of buildings and paved surface. Once the classification was completed, students chose an area for reforestation identified in CITYgreen, while raising funds for the purchase of trees for the project. Before completing the project, students reviewed tenets of landscape ecology, civic ecology education, and benefits of urban forestry. At the completion of the project, students reviewed service-learning aspects …

Long-Term Study Of Prescribed Fire Effects On Stand Dynamics And Oak Regeneration Potentials In Degraded Upland Oak-Hickory Stands In Northwestern Arkansas, Mason C. Danheim, Kathryn R. Kidd Dr, Hal O. Liechty Dr, Brian P. Oswald Dr

Electronic Theses and Dissertations

Upland oak-hickory forests in the Ozark Mountains of northwestern Arkansas and south central Missouri were impacted by oak decline during the early 2000s. This decline event was caused by predisposing (e.g., mature, dense stand conditions), inciting (i.e., drought), and contributing (e.g., red oak borer, E. rufulus H., outbreak) factors. Immediately following onset of the decline, substantial crown dieback and tree mortality, particularly for two red oak species (northern red oak, Quercus rubra Michx. and black oak, Q. velutina Lam.), were observed. In addition, densities of advanced oak regeneration were inadequate at this time, resulting in poor regeneration potentials for …

Visitor Characteristics, Attitudes, And Management Preferences Of The Bob Marshall Wilderness Complex, Samuel J. Rhodes

Electronic Theses and Dissertations

The Bob Marshall Wilderness Complex (BMWC) encompasses 3 federal wilderness areas and spans over 1.5 million acres of iconic mountains and valleys in northwestern Montana. Here visitors can find a plethora of recreation opportunity that give access to some of the most rugged country that can be found in the lower 48 states. However, managing wilderness areas comes with the challenge of both preserving the natural resources found within their borders and enabling opportunities for recreational experiences. Wilderness social scientists always have striven to determine the type of visitors coming to wilderness, and see what sorts of experiences they pursue. …

Comparison Of The Survival And Growth Of West Gulf Coastal Plain Pine In East Texas, Jamie Hooker

Electronic Theses and Dissertations

West Gulf Coastal Plain provenance loblolly (Pinus taeda L.), longleaf (Pinus palustris Mill.), shortleaf (Pinus echinata Mill.), and slash pines (Pinus elliottii Engelm.) were planted in East Texas to compare initial growth and survival. Containerized seedlings were planted in December 2015 on three study sites in Shelby, Houston, and Cherokee counties using a randomized complete block design. Seedlings were measured in January-February 2016 and again January-February 2017, January 2018, and January 2019. Three years after planting, survival was best (76.4%) in Houston County and was lowest in Cherokee County (26.4). Damage by Texas leafcutter ants (Atta …

A Qualitative Case Study Of Student Persistence In A Bachelor Of Science In Forestry Program, Maxwell Holmes

Electronic Theses and Dissertations

Educational leaders in forestry have been challenged to increase and diversify the pipeline of ‘society ready’ foresters. To meet these challenges, leaders must shift their focus to student retention. By understanding the factors that influence student engagement and persistence, these leaders will be better positioned to support students in forestry programs, thus positively impacting retention. This qualitative case study investigated student persistence of second-year forestry students in an undergraduate forestry program. The study was guided by Social Cognitive Theory and Social Capital Theory and explored the malleable psychosocial mechanisms of self-efficacy, sense of belonging, emotion, and well-being proposed by Kahu …

Outdoor Education’S Relationship To Adolescent Behavior And Academic Performance In Two East Texas Middle Schools, Trenton Stiefel

Electronic Theses and Dissertations

Historically, a key part of a child’s development was their exposure to and relationship with the world outdoors – nature. The current movement to promote the inclusion of environmental and outdoor education into curricular and extracurricular activities stems from the mounting evidence that experiences in the outdoors may improve a child’s behavior and mood, as well as improve their academic performance. This mixed-methods study hoped to discover whether or not, on average, children improve their academic performance and/or their individual behavior in school when provided with outdoor education learning experiences. The mindset used in outdoor education research may have to …

Using The Forestry Reclamation Approach For Reclaimed Surface Mineland In The Western Gulf: Effects On Pinus Taeda Seedling Growth And Survival, Cassie Phillips, Jeremy Stovall, Hans Williams, Kenneth Farrish

Electronic Theses and Dissertations

While land reclamation efforts of surface mines have considerably increased soil stability since the implementation of SMCRA (Surface Mining Control and Reclamation Act), research suggests that resulting soil compaction hinders the productivity of forests post-mining. The Forestry Reclamation Approach (FRA) was developed to improve forest health in the Appalachian region through a five-step process that minimizes soil compaction and establishes a productive forest. The FRA has not yet been tested in the western Gulf Coastal Plain (GCP). The higher clay content of some GCP soils and the dearth of coarse fragments (e.g. cobbles, stones and boulders) may affect reclamation practices …

The Transesterification Of Hickory Nuts Into Biodiesel Fuel, Hannah Trauger, Madilynn Dewell, Jahida A. Mendoza

Undergraduate Research Conference

• Biodiesel fuels can be produced from a fat and an alcohol via transesterification

• Hickory nuts have a high fat content (~60 % by weight)

• Can nuts from shagbark hickory (Carya ovata) be used to produce a biodiesel fuel using existing acidcatalyzed transesterification methods?

Extraction And Quantification Of Hydrolyzable Tannins In Acorns From Different Species Of Oak Trees (Quercus Spp.), Sarah Browning, Marshall E. Woodruff

Undergraduate Research Conference

Do white-tailed deer (Odocoileus virginianus) prefer to eat certain types of acorns based on tannin content?

Hydrolyzable tannins consist of gallate groups connected via ester linkages to a carbohydrate (D-glucose)

The Prussian Blue method was used to determine hydrolyzable tannin content

Effectiveness Of Plant Species For Removing Atmospheric Ammonia, Marife B. Anunciado, Sheryll B. Jerez, Hans Williams, Joey Bray, Dean W. Coble, Rena Saito

Faculty Publications

Six plant species of Yaupon, Eastern red cedar, American holly, Arizona cypress, Arborvitae and Roughleaf dogwood were utilized to determine their effectiveness in the removal of atmospheric ammonia. All species were exposed to three ammonia levels (1, 5 and 10 ppm) in an environmental chamber. Foliar ammonia content was quantified using an enzymatic technique. The effects of exposure to ammonia on the physiological responses (e.g. photosynthetic activity, stomatal conductance, and transpiration rate) of plants in ambient condition were also determined using an open design photosynthetic gas exchange system. Foliar ammonia content was significantly different among the six plant species (p<0.0001) with Eastern red cedar exhibiting the highest content. The physiological responses differed significantly depending on the plant species and the ammonia treatment level. The photosynthetic response of plants to the presence of ammonia was mixed. At low exposure level, all species except Arborvitae had decreased photosynthetic activity, reducing by as much as 44.5% for Yaupon. At the highest concentration, however, Yaupon’s photosynthetic activity improved by about 10%. Exposure to ammonia caused increased stomatal conductance and transpiration rate on American holly and Arizona cypress, making them more susceptible to water loss.

Weed Control And Overstory Reduction Improve Survival And Growth Of Under‐Planted Oak And Hickory Seedlings, Luke B. Oliver, Jeremy Stovall, Chris E. Comer, Hans Williams, Matt E. Symmank

Faculty Publications

Weed control and overstory reduction are important silvicultural treatments for improving survival and growth of under‐planted oak and hickory seedlings. Mast‐producing trees in the bottomland forests of the blackland prairie and Post Oak Savannah ecoregions of Texas have declined in abundance. Oaks and hickories have been replaced by more shade‐tolerant species, including green ash (Fraxinus pennsylvanica Marshall) and sugarberry (Celtis laevigata Willd.), which do not produce significant hard mast for priority wildlife species. A split‐plot experiment design was installed on three sites at Richland Creek Wildlife Management Area in Freestone County, Texas, studying the effects of canopy coverage …

Student Led Area Measurement Assessments Using Virtual Globes And Pictometry Web-Based Interface Within An Undergraduate Spatial Science Curriculum, David Kulhavy, I-Kuai Hung, Daniel Unger, Yanli Zhang

Faculty Publications

The use of Virtual Globes and Pictometry continues to expand and develop in undergraduate spatial science education. Spatial science undergraduates measured the area of 30 rectangles on the earth’s surface and compared them to Pictometry hyperspectral imagery measurements within a web-based interface and the Google Earth interface compared to ArcGIS Explorer, Map Developers and ArcMap using the ArcMap 10.5.2 interface. An analysis of variance of the absolute mean area errors (p-value of 0.009271) concluded the accuracy of the five area measurements were statistically different at the 95% confidence interval. A Tukey pair-wise test found that the Pictometry and Google Earth …

Distribution Of Contaminants In The Environment And Wildlife Habitat Use: A Case Study With Lead And Waterfowl On The Upper Texas Coast, Brian Kearns, Stephen Mcdowell, Jena A. Moon, Elizabeth Rigby, Warren C. Conway, David A. Haukos

Faculty Publications

The magnitude and distribution of lead contamination remain unknown in wetland systems. Anthropogenic deposition of lead may be contributing to negative population-level effects in waterfowl and other organisms that depend on dynamic wetland habitats, particularly if they are unable to detect and differentiate levels of environmental contamination by lead. Detection of lead and behavioral response to elevated lead levels by waterfowl is poorly understood, but necessary to characterize the risk of lead-contaminated habitats. We measured the relationship between lead contamination of wetland soils and habitat use by mottled ducks (Anas fulvigula) on the Upper Texas Coast, USA. Mottled …