Forest Sciences Commons^™

Site Factors Influence On Herbaceous Understory Diversity In East Texas Pinus Palustris Savannas, Brooke Mccalip, Brian Oswald, Kathryn R. Kidd, Yuhi Weng, Kenneth Farrish Phd

Faculty Publications

Longleaf pine (Pinus palustris) savannas were once dominant across the southeastern U.S., including East Texas and parts of western and central Louisiana. The diverse understory associated with these historical savannas may occasionally be seen today, but not often in longleaf pine ecosystems. This project aimed to define east Texas site characteristics that are necessary to support these ecosystems with a dense and diverse herbaceous understory with little to no midstory cover. Fifty-nine plots across three study sites were established to evaluate the influence of overstory cover, basal area, aspect, elevation, and slope on the number of plant genera present. Forest …

Accuracy Of Unmanned Aerial System (Drone) Height Measurements, Daniel Unger, I-Kuai Hung, David Kulhavy, Yanli Zhang, Kai Busch-Peterson

Faculty Publications

Vertical height estimates of earth surface features using an Unmanned Aerial System (UAS) are important in natural resource management quantitative assessments. An important research question concerns both the accuracy and precision of vertical height estimates acquired with a UAS and to determine if it is necessary to land a UAS between individual height measurements or if GPS derived height versus barometric pressure derived height while using a DJI Phantom 3 would affect height accuracy and precision. To examine this question, height along a telescopic height pole on the campus of Stephen F. Austin State University (SFASU) were estimated at 2, …

Integrating Unmanned Aircraft Systems To Measure Linear And Areal Features Into Undergraduate Forestry Education, Reid Viegut, David Kulhavy, Daniel Unger, I-Kuai Hung, Brian Humphreys

Faculty Publications

The use of Unmanned Aircraft Systems (UAS) in undergraduate forestry education continues to expand and develop. Accuracy of data collection is an important aspect of preparation for "society-ready" foresters to meet the complex sustainable environment managing for ecological, social and economic interests. Hands-on use of a DJI Phantom 4 Pro UAS by undergraduates to measure the length and area of 30 linear features and areal features on Earth's surface were estimated. These measurements were compared (measured within the ArcMap 10.5.2 interface) to hyperspectral Pictometry imagery measured on the web-based interface and the Google Earth Pro interface. Each remotely estimated measurement …

Surface And Subsurface Tillage Effects On Mine Soil Properties And Vegetative Response, H. Z. Angel, Jeremy Stovall, Hans Michael Williams, Kenneth W. Farrish, Brian P. Oswald, J. L. Young

Faculty Publications

Soil compaction is an important concern for surface mine operations that require heavy equipment for land reclamation. Excessive use of rubber-tired equipment, such as scraper pans, may cause mine soil compaction and hinder the success of revegetation efforts. However, information is limited on management strategies for ameliorating the potential compacting effects of scraper pans, particularly during site preparation for loblolly pine (Pinus taeda L.) plantations. Three forms of tillage and one control were replicated five times on surface mined land in the west Gulf Coastal Plain: no tillage (NT), disking (D), single-ripping + disking (R+D), and cross-ripping + disking …

Food Habits Of Sympatric Pitvipers From The West Gulf Coastal Plain, Usa, Christopher M. Schalk, Toni Trees, Joshua B. Pierce, D. Craig Rudolph

Faculty Publications

Widespread species that occupy multiple communities exhibit geographic variation in their natural history due to the ecological context of the local community. An animal’s food habitats are a central component to understanding its natural history and ecological role within its community—information that is critical to understanding resource needs of a species, mechanisms of species coexistence, and energy flow in food webs (Litvaitis 2000; Schalk et al. 2014). This information is also crucial for predicting the response of populations to changes in resource availability and, if necessary, inform mitigation strategies (Holycross and Mackessy 2002)

On-Road Emissions Of Ammonia: An Underappreciated Source Of Atmospheric Nitrogen Deposition, Mark E. Fenn, Andrzej Bytnerowicz, Susan L. Schilling, Dena M. Vallano, Erika S. Zavaleta, Stuart B. Weiss, Connor Morozumi, Linda H. Geiser, Kenneth Hanks

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

We provide updated spatial distribution and inventory data for on-road NH₃ emissions for the continental United States (U.S.) On-road NH₃ emissions were determined from on-road CO₂ emissions data and empirical NH₃:CO₂ vehicle emissions ratios. Emissions of NH₃ from on-road sources in urbanized regions are typically 0.1– 1.3 t km⁻² yr⁻¹ while NH₃ emissions in agricultural regions generally range from 0.4–5.5 t km⁻² yr⁻¹, with a few hot spots as high as 5.5–11.2 t km⁻² yr⁻¹. Counties with higher vehicle NH3 emissions than from agriculture …

Ecological-Economic Assessment Of The Effects Of Freshwater Flow In The Florida Everglades On Recreational Fisheries, Christina Estela Brown, Mahadev G. Bhat, Jennifer S. Rehage, Ali Mirchi, Ross Boucek, Victor Engel, Jerald S. Ault, Pallab Mozumder, David Watkins, Michael Sukop

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

This research develops an integrated methodology to determine the economic value to anglers of recreational fishery ecosystem services in Everglades National Park that could result from different water management scenarios. The study first used bio-hydrological models to link managed freshwater inflows to indicators of fishery productivity and ecosystem health, then link those models to anglers' willingness-to-pay for various attributes of the recreational fishing experience and monthly fishing effort. This approach allowed us to estimate the foregone economic benefits of failing to meet monthly freshwater delivery targets. The study found that the managed freshwater delivery to the Park had declined substantially …

Agroforestry Standards For Regenerative Agriculture [Review], Craig R. Elevitch, D. Niki Mazaroli, Diane Ragone

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Agroforestry is increasingly being recognized as a holistic food production system that can have numerous significant environmental, economic, and social benefits. This growing recognition is paralleled in the USA by the budding interest in regenerative agriculture and motivation to certify regenerative practices. Current efforts to develop a regenerative agriculture certification offer an opportunity to consider agroforestry’s role in furthering regenerative goals. To understand this opportunity, we first examine how agroforestry practices can advance regenerative agriculture’s five core environmental concerns: soil fertility and health, water quality, biodiversity, ecosystem health, and carbon sequestration. Next, we review a subset of certification programs, standards, …

Bankfull Width, Kevin W. Custer, Eric B. Borth, Julia I. Chapman, Ryan W. Mcewan

Data Files

No abstract provided.

Overstory, Erin C. Rowekamp, Eric B. Borth, Julia I. Chapman, Ryan W. Mcewan

Data Files

No abstract provided.

Herbaceous Vegetation: April, Julia I. Chapman, Margaret E. Maloney, Erin C. Rowekamp, Mitchell J. Kukla, Sean D. Mahoney, Eric B. Borth, Ryan W. Mcewan

Data Files

April

Macroinvertebrates, Mitchell J. Kukla, Corey Kuminecz, Margaret E. Maloney, Joseph Murphy, Taylor M. Buskey, Jenea I. Adams, Michelle N. Little, Eric B. Borth, Taylor M. Sparbanie, Sean D. Mahoney, Kevin W. Custer, Julia I. Chapman, Ryan W. Mcewan

Data Files

No abstract provided.

Conventional Method Comparison Data (Ves And Hess), Margaret E. Maloney, Eric B. Borth, Julia I. Chapman, Ryan W. Mcewan

Data Files

No abstract provided.

Herbaceous Vegetation: June, Julia I. Chapman, Margaret E. Maloney, Erin C. Rowekamp, Mitchell J. Kukla, Sean D. Mahoney, Eric B. Borth, Ryan W. Mcewan

Data Files

June

Lonicera Maackii Leaf Feeding Tests: Survival, Growth, Loss Of Leaf Mass, Kevin W. Custer, Julia I. Chapman, Ryan W. Mcewan

Data Files

Lymnaea stagnalis, Hyalella Azteca, and Allocapnia spp.

Lonicera Maackii Leaf Leachate Toxicity: Physicochemical Data, Eric B. Borth, Kevin W. Custer, Julia I. Chapman, Ryan W. Mcewan

Data Files

Lymnaea stagnalis and Hyalella azteca

Phosphorus Limitation Of Aboveground Production In Northern Hardwood Forests, Shinjini Goswami, Melany C. Fisk, Matthew A. Vadeboncoeur, Mariann Garrison-Johnston, Ruth D. Yanai, Timothy J. Fahey

All Materials

Forest productivity on glacially derived soils with weatherable phosphorus (P) is expected to be limited by nitrogen (N), according to theories of long-term ecosystem development. However, recent studies and model simulations based on resource optimization theory indicate that productivity can be co-limited by N and P. We conducted a full factorial N × P fertilization experiment in 13 northern hardwood forest stands of three age classes in central New Hampshire, USA, to test the hypothesis that forest productivity is co-limited by N and P. We also asked whether the response of productivity to N and P addition differs among species …

Carbon Fluxes And Interannual Drivers In A Temperate Forest Ecosystem Assessed Through Comparison Of Top-Down And Bottom-Up Approaches, Andrew P. Ouimette, Scott V. Ollinger, Andrew D. Richardson, David Y. Hollinger, Trevor F. Keenan, Lucie C. Lepine, Matthew A. Vadeboncoeur

All Materials

Despite decades of research, gaining a comprehensive understanding of carbon (C) cycling in forests remains a considerable challenge. Uncertainties stem from persistent methodological limitations and the difficulty of resolving top-down estimates of ecosystem C exchange with bottom-up measurements of individual pools and fluxes. To address this, we derived estimates and associated uncertainties of ecosystem C fluxes for a 100-125 year old mixed temperate forest stand at the Bartlett Experimental Forest, New Hampshire, USA, using three different approaches: (1) tower-based eddy covariance, (2) a biometric approach involving C flux measurements of individual ecosystem subcomponents, and (3) an inventory approach involving changes …

Hydrological Niche Segregation Defines Forest Structure And Drought Tolerance Strategies In A Seasonal Amazon Forest, Mauro Brum, Matthew A. Vadeboncoeur, Valeriy Ivanov, Heidi Asbjornsen, Scott Saleska, Luciana F. Alves, Deliane Pinha, Jadson D. Dias, Luiz E O C Aragão, Fernanda Barros, Paulo Bittencourt, Luciano Pereira, Rafael S. Oliveira

All Materials

1. The relationship between rooting depth and above‐ground hydraulic traits can potentially define drought resistance strategies that are important in determining species distribution and coexistence in seasonal tropical forests, and understanding this is important for predicting the effects of future climate change in these ecosystems.
2. We assessed the rooting depth of 12 dominant tree species (representing c. 42% of the forest basal area) in a seasonal Amazon forest using the stable isotope ratios (δ¹⁸O and δ²H) of water collected from tree xylem and soils from a range of depths. We took advantage of a major ENSO‐related …

Resource Selection Of Free-Ranging Horses Influenced By Fire In Northern Canada, Sonja E. R. Leverkus, Samuel D. Fuhlendorf, Marten Geertsema, Brady W. Allred, Mark Gregory, Alexandre R. Bevington, David M. Engle, J. Derek Scasta

Human–Wildlife Interactions

Free-ranging or feral horses (Equus ferus caballus) were important to the livelihood of First Nations and indigenous communities in Canada. The early inhabitants of the boreal region of British Columbia (BC) capitalized on naturally occurring wildfires and anthropogenic burning to provide forage for free-ranging horses and manage habitat for wildlife. This form of pyric herbivory, or grazing driven by fi re via the attraction to the palatable vegetation in recently burned areas, is an evolutionary disturbance process that occurs globally. However, its application to manage forage availability for free-ranging horses has not been studied in northern Canada. Across Canada, there …

The Three Creeks Allotment Consolidation: Changing Western Federal Grazing Paradigms, Taylor Payne

Human–Wildlife Interactions

The federal government owns approximately 47% of all land in the western United States. In the state of Utah, about 64% of the land base is managed by the federal Bureau of Land Management (BLM) and the U.S. Forest Service (USFS). The government has historically issued permits to owners of private lands to allow the owners to graze their livestock on public lands. The permits (allotments) are generally of 10-year duration and allow for an annual season of use. In some cases, continued and repeated historical annual grazing practices may not be ideal for permit holders and their communities nor …

Restoration And Tree Drought Resistance In Coast Redwood-Douglas-Fir Forests At Redwood National Park, California, Laura Lalemand

Cal Poly Humboldt theses and projects

With the growing impacts of climate change worldwide and great uncertainty about forests’ vulnerability to a changing climate in the Pacific Northwest, knowledge of coast redwood forest response is crucial. Many of the studies investigating forest response to drought focus on inland forest types rather than coastal forests. This study examined tree growth and drought response in coastal forests at restoration thinning sites, evaluating responses to local climate, tree-level competition, and site-level factors. Tree cores were extracted from previously harvested stands at three restoration sites in Redwood National Park, California, from both thinned and unthinned stands. Douglas-fir (Pseudotsuga menziesii …

Implications Of Unmanned Aircraft Systems And Sense Of Place: A Case Study In The Mono Basin, Sara Elizabeth Matthews

Cal Poly Humboldt theses and projects

This paper contributes to an understanding of the social implications of using UAS in natural resource areas; specifically, the ways in which these tools impact human constructed sense of place. This paper draws on in-depth interviews and document analysis to (a) develop an understanding of place meanings held among Mono Basin stakeholders and (b) define the ways in which increased UAS presence may interact with these visions of place.

In short, this research shows that sense of place in this rural area is influential in the way that UAS are received by local stakeholders. The changing nature of place meanings …

Assessing Spatio-Temporal Patterns Of Forest Decline Across A Diverse Landscape In The Klamath Mountains Using A 28-Year Landsat Time-Series Analysis, Drew S. Bost

Cal Poly Humboldt theses and projects

Rates of tree mortality in California and the Pacific Northwest have greatly increased in recent years, driven largely by pest and pathogen outbreaks as well as the effects of hotter, warmer droughts. While there have been a multitude of regional-scale assessments of mortality and forest decline, landscape-level studies are necessary to better identify forests that are most vulnerable to decline and to anticipate future changes. This need is particularly notable in the remote and little-studied mountains of northwest California, which are renowned for their diverse, heterogeneous vegetation types. A recent observation of elevated levels of Shasta red fir (Abies …

Productivity And Cost Of A Cut-To-Length Commercial Thinning Operation In A Northern California Redwood Forest, Kigwang Baek

Cal Poly Humboldt theses and projects

Cut-to-length (CTL) harvesting systems have recently been introduced to the redwood forests of California’s north coast. These machines are being used to commercially thin dense redwood (Sequoia sempervirens) stands which tend to form clumps of stems that vigorously sprout from stumps after a harvest. One of the challenges is to avoid damaging residual trees which can decrease productivity, increase costs, and lower the market value of trees. The goal of this study was to evaluate the productivity and costs associated with CTL systems used in a redwood forests and use that data to develop equations for predictions. Time …

Impacts On Soils And Residual Trees From Cut-To-Length Thinning Operations In California's Redwood Forests, Kyungrok Hwang

Cal Poly Humboldt theses and projects

In northern California, a cut-to-length (CTL) system was used for the first time to harvest young redwood forests (Sequoia sempervirens (Lamb. ex D. Don) Endl.). However, landowners and public agencies are concerned about the potential negative impacts of CTL logging to soils and residual trees since the extent and amount of CTL impacts are unknown in these forests. This study was designed to (1) determine soil physical property using bulk density (BD) and hydraulic conductivity (HC) (2) examine the characteristics of stand damage after CTL harvesting, and (3) compare the scar size differences between tree growing patterns (individuals vs. …

Game Of Tones: Sugars, Organic Acids, And Phenolics In Green And Purple Asparagus (Asparagus Officinalis L.) Cultivars, Ana Slatnar, Maja Mikulic Petkovsek, Franci Stampar, Robert Veberic, Jasmina Horvat, Marijana Jakse, Helena Sircelj

Turkish Journal of Agriculture and Forestry

The content of selected compounds was compared among different spear sections (the tip, the middle, and the base) of green (Ariane F1, Dariana F1, Darsiane F1, Mondeo F1, Primaverde F1, and Viridis F1) and purple (Burgundine F1 and Pacific Purple F1) asparagus cultivars. Sugars, organic acids, anthocyanins, flavonols, flavones, and hydroxycinnamic acids were determined by HPLC. No significant differences in the content of organic acids, sugars, and hydroxycinnamic acids were detected among cultivars. However, purple cultivars contained the highest levels of anthocyanins. The content of flavonols, flavones, hydroxycinnamic acids, and total phenols were not color-dependent. High flavonol content was characteristic …

Drought Stress Responses Of Seedlings Of Two Oak Species (Quercus Cerris And Quercus Robur), Ayşe Deli̇göz, Esra Bayar

Turkish Journal of Agriculture and Forestry

Effects of drought stress on growth, predawn xylem water potential (ψpd), osmotic solutes (soluble sugar and proline), and stomatal conductance were assessed in two oak (Quercus cerris L. and Quercus robur L.) seedlings. Seedlings of both species were subjected to three drought treatments with the following irrigation intervals: well-watered (control: irrigation every 2-3 days), moderate drought stress (irrigation every 15 days), and severe drought stress (irrigation every 30 days). Drought-stressed seedlings of Q. cerris and Q. robur had more negative predawn xylem water potential than their well-watered seedlings. In Q. cerris, root collar diameter and root dry weights were negatively …

Prototype Twin Vacuum Disk Metering Unit For Improved Seed Spacing Uniformity Performance At High Forward Speeds, Adnan Deği̇rmenci̇oğlu, Bülent Çakmak, Arzu Yazgi

Turkish Journal of Agriculture and Forestry

The objective of this study was to design and develop a prototype twin vacuum disk metering unit so that seeding can be achieved at higher forward speeds while reducing the peripheral speed of the vacuum disk for improved seed spacing uniformity performance and increased field work capacity. In order to meet this objective, a new precision seeding unit with twin vacuum disks, each being a mirrored view of the other and geometrically the same, was designed in animated drafting software and then it was manufactured and used for the laboratory experiments. Three crop seeds were used to determine the performance …

Boron And Maturity Effects On Biochemical Parameters And Antioxidantactivity Of Pepper (Capsicum Annuum L.) Cultivars, Eleana Sarafi, Anastasios Siomos, Pavlos Tsouvaltzis, Christos Chatzissavvidis, Ioannis Therios

Turkish Journal of Agriculture and Forestry

Pepper fruit (Capsicum annuumL.) is one of the best sources of carotenoids, carbohydrates, flavonoids, phenols, and antioxidant activity important in the human diet. The levels of bioactive compounds are variable and may be affected by cultivar, maturity stage, and boron concentration in the soil solution. A greenhouse experiment was conducted with the pepper cultivars Solario, Osho, Odysseo, and Arlequin treated with 5 boron concentrations (0.5, 1, 2.5, 5, and 10 mg B L-1) for 70 days. Fruits were sampled at 40 and 70 days and the concentration of carbohydrates, carotenoids, flavonoids, total phenols, and antioxidant activity (FRAP, DPPH) were measured. …