Physical Sciences and Mathematics Commons^™

Seasonal Dynamics Of Lipid Metabolism And Energy Storage In The Brazilian Free-Tailed Bat, Elizabeth J. Rogers, Amie S. Sommers, Liam P. Mcguire

School of Natural Resources: Faculty Publications

As small, flying, mammalian endotherms, insectivorous bats are adapted to operate at high levels of energy expenditure. In response to seasonally variable challenges, we predicted that bats should balance energy budgets by flexibly adjusting aspects of their physiology or behavior in ways that elevate metabolic capacity. We examined variation in energy storage and pathways for oxidative metabolism in Brazilian free-tailed bats (Tadarida brasiliensis) related to estimated costs associated with reproduction and migration. We collected pectoral muscle and liver from female T. brasiliensis at six time points during the summer and fall and measured changes in the activity of four enzymes …

Fish Community Response To In-Channel Woody Debris In A Channelized River System, Michael W. Archer, Brenda M. Pracheil, Alexandrea E. Otto, Mark A. Pegg

School of Natural Resources: Faculty Publications

Additions of large wood (LW) have become a go-to technique for recovering altered river ecosystems. However, successful applications of this technique are generally limited to unchannelized rivers and headwater streams. Channelization of rivers, that is, engineering river channels to reduce recruitment and retention of in-channel structure, may, by definition, limit success of this restoration technique. Moreover, sufficient time has passed (a century or more) since initial channelization of many large rivers that portions of the fish community associated with LW may have become extirpated. Thus, the maxim that LW leads to a positive fish community response may not hold true. …

Migratory Shorebird Adheres To Bergmann’S Rule By Responding To Environmental Conditions Through The Annual Lifecycle, Daniel Gibson, Angela D. Hornsby, Mary B. Brown, Jonathan B. Cohen, Lauren R. Dinan, James D. Fraser, Meryl J. Friedrich, Cheri L. Gratto-Trevor, Kelsi L. Hunt, Matthew Jeffery, Joel G. Jorgensen, Peter W.C. Paton, Samantha G. Robinson, Jen Rock, Michelle L. Stantial, Chelsea E. Weithman, Daniel H. Catlin

School of Natural Resources: Faculty Publications

The inverse relationship between body size and environmental temperature is a widespread ecogeographic pattern. However, the underlying forces that produce this pattern are unclear in many taxa. Expectations are particularly unclear for migratory species, as individuals may escape environmental extremes and reorient themselves along the environmental gradient. In addition, some aspects of body size are largely fixed while others are environmentally flexible and may vary seasonally. Here, we used a long-term dataset that tracked multiple populations of the migratory piping plover Charadrius melodus across their breeding and non-breeding ranges to investigate ecogeographic patterns of phenotypically flexible (body mass) and fixed …

Discontinuity Analysis Reveals Alternative Community Regimes During Phytoplankton Succession, David G. Angeler, Craig R. Allen, Dirac L. Twidwell Jr., Monika Winder

School of Natural Resources: Faculty Publications

It is well-recognized in plankton ecology that phytoplankton development can lead to distinct peaks (i.e., blooms) during spring and summer. We used a 5-year (2007–2011) phytoplankton data set and utilized discontinuity analysis to assess resilience attributes of spring and summer blooms based on the cross-scale resilience model. Using the size structure (i.e., cross-scale structure as an indicator of resilience) in the sampled plankton data, we assessed whether spring and summer blooms differ substantially between but not within blooms; that is, whether they comprise alternative community regimes. Our exploratory study supported this expectation and more broadly resilience theory, which posits that …

Resistivity Arrays As An Early Warning System For Monitoring Runoff Holding Ponds, Bryan L. Woodbury, Roger A. Eigenberg, Trenton E. Franz

School of Natural Resources: Faculty Publications

Monitoring wells are installed to intercept contaminants inadvertently discharged from inground structures designed to retain salt-affected wastewaters; however, several difficulties with collection and data interpretation limit their effectiveness. Therefore, improved monitoring methods are needed. The objective of this study was to evaluate the effectiveness of resistivity array technology as an early warning system to monitor for unintended basin discharge. Subsurface resistivity arrays were installed at two Nebraska sites: a beef cattle feedyard located at the U.S. Meat Animal Research Center, Clay Center, Nebraska (FyA) and a commercial cattle feeding operation (FyB). Monitoring well data did not identify any unintended discharge …

Factors Influencing Ranchers’ Intentions To Manage For Vegetation Heterogeneity And Promote Cross-Boundary Management In The Northern Great Plains, Maggi S. Sliwinski, Mark E. Burbach, Larkin A. Powell, Walter H. Schacht

School of Natural Resources: Faculty Publications

Most private grasslands in the Great Plains are managed with the goal to optimize beef production, which tends to homogenize rangeland habitats. The subsequent loss of vegetation heterogeneity on private lands is detrimental to ecosystem function. However, conservation planners should understand the factors that lead to variation in management of rangelands. We used a mail survey targeted to ranchers in counties with intact rangeland in North Dakota, South Dakota, and Nebraska in 2016 to examine factors predicted to be related to attitudes about strategies leading to heterogeneity such as innovativeness and low risk aversion, and intended behaviors associated with creation …

Environmental Controls On The Seasonal Variation In Gas Exchange And Water Balance In A Near-Coastal Mediterranean Pinus Halepensis Forest, Mariangela N. Fotelli, Evangelia Korakaki, Spyridon A. Paparrizos, Kalliopi Radoglou, Tala Awada, Andreas Matzarakis

School of Natural Resources: Faculty Publications

Aleppo pine (Pinus halepensis Mill.) is widespread in most countries of the Mediterranean area. In Greece, Aleppo pine forms natural stands of high economic and ecological importance. Understanding the species’ ecophysiological traits is important in our efforts to predict its responses to ongoing climate variability and change. Therefore, the aim of this study was to assess the seasonal dynamic in Aleppo pine gas exchange and water balance on the leaf and canopy levels in response to the intra-annual variability in the abiotic environment. Specifically, we assessed needle gas exchange, water potential and δ13C ratio, as well as tree sap flow …

Seasonal Salinization Decreases Spatial Heterogeneity Of Sulfate Reducing Activity, Valerie A. Schoepfer, Amy J. Burgin, Terry D. Loecke, Ashley M. Helton

School of Natural Resources: Faculty Publications

Evidence of sulfate input and reduction in coastal freshwater wetlands is often visible in the black iron monosulfide (FeS) complexes that form in iron rich reducing sediments. Using a modified Indicator of Reduction in Soils (IRIS) method, digital imaging, and geostatistics, we examine controls on the spatial properties of FeS in a coastal wetland fresh-to-brackish transition zone over a multi-month, drought-induced saltwater incursion event. PVC sheets (10 - 15 cm) were painted with an iron oxide paint and incubated vertically belowground and flush with the surface for 24 h along a salt-influenced to freshwater wetland transect in coastal North Carolina, …

Leveraging Image Analysis For High-Throughput Plant Phenotyping, Sruti Das Choudhury, Ashok Samal, Tala Awada

School of Natural Resources: Faculty Publications

The complex interaction between a genotype and its environment controls the biophysical properties of a plant, manifested in observable traits, i.e., plant’s phenome, which influences resources acquisition, performance, and yield. High-throughput automated image-based plant phenotyping refers to the sensing and quantifying plant traits non-destructively by analyzing images captured at regular intervals and with precision. While phenomic research has drawn significant attention in the last decade, extracting meaningful and reliable numerical phenotypes from plant images especially by considering its individual components, e.g., leaves, stem, fruit, and flower, remains a critical bottleneck to the translation of advances of phenotyping technology into genetic …

Convergence Science In The Anthropocene: Navigating The Known And Unknown, David G. Angeler, Craig R. Allen, Ana Carnaval

School of Natural Resources: Faculty Publications

1. Rapidly changing ecological and social systems currently pose significant societal challenges. Navigating the complexity of social-ecological change requires ap- proaches able to cope with, and potentially solve, both foreseen and unforeseen societal challenges.

2. The emergent field of convergence addresses the intricacies of such challenges, and is thus relevant to a broad range of interdisciplinary issues.

3. This paper suggests a way to conceptualize convergence research. It discusses how it relates to two major societal challenges (adaptation, transformation), and to the generation of policy-relevant science. It also points out limitations to the further development of convergence research.

Reflecting On Efforts To Design An Inclusive Citizen Science Project In West Baltimore, Amanda E. Sorensen, Rebecca C. Jordan, Shannon L. Ladeau, Dawn Biehler, Sacoby Wilson, John-Henry Pitas, Paul T. Leisnham

School of Natural Resources: Faculty Publications

Citizen science (CS) has been an increasingly utilized means by which scientists leverage members of the public to increase the amount of data collected and analyzed. However, the underrepresentation of individuals from certain socio-cultural groups can have consequences that can manifest in the scientific outcomes of those CS projects such as biases in the data. Additionally, this underrepresentation can potentially affect long-term viability and support of CS as a community of practice. CS programs that promote greater inclusivity would likely provide opportunities for communities to define, investigate, and address pressing issues in collaboration with professional scientists. In this paper we …

Sampling Related Individuals Within Ponds Biases Estimates Of Population Structure In A Pond‐Breeding Amphibian, Kyle A. O'Connell, Kevin P. Mulder, Jose Maldonado, Kathleen L. Currie, Dennis M. Ferraro

School of Natural Resources: Faculty Publications

Effective conservation and management of pond‐breeding amphibians depends on the accurate estimation of population structure, demographic parameters, and the influence of landscape features on breeding‐site connectivity. Population‐level studies of pond‐breeding amphibians typically sample larval life stages because they are easily captured and can be sampled nondestructively. These studies often identify high levels of relatedness between individuals from the same pond, which can be exacerbated by sampling the larval stage. Yet, the effect of these related individuals on population genetic studies using genomic data is not yet fully understood. Here, we assess the effect of within‐pond relatedness on population and landscape …

Photosynthesis, Yield And Raw Material Quality Of Sugarcane Injured By Multiple Pests, José A.S. Rossato Jr, Leonardo L. Madaleno, Márcia J.R. Mutton, Leon Higley, Odair A. Fernandes

School of Natural Resources: Faculty Publications

Understanding sugarcane (Saccharum spp.) response to multiple pest injury, sugarcane borer (Diatraea saccharalis) and spittlebug (Mahanarva fimbriolata), is essential to make better management decisions. Moreover, the consequences of both pests on the sugarcane raw material quality have not yet been studied. A field experiment was performed in São Paulo State, Brazil, where sugarcane plants were exposed to pests individually or in combination. Plots consisted of a 2-m long row of caged sugarcane plants. Photosynthesis was measured once every 3 months (seasonal measurement). Yield and sugar production were assessed. The measured photosynthesis rate was negatively affected by both borer and spittlebug …

Irrigation Impacts On Minimum And Maximum Surface Moist Enthalpy In The Central Great Plains Of The Usa, Tianyi Zhang, Rezaul Mahmood, Xiaomao Lin, Roger A. Pielke Sr.

School of Natural Resources: Faculty Publications

Agricultural activities notably alter weather and climate including near-surface heat content. However, past research primarily focused on dry bulb temperature without considering the role of water vapor (dew point temperature) on surface air heat content. When using dry bulb temperature trends to assess these changes, for example, not including concurrent trends in absolute humidity can lead to errors in the actual rate of warming or cooling. Here we examined minimum and maximum surface moist enthalpy, which can be expressed as “equivalent temperature.” Using hourly climate data in the Central Great Plains (Nebraska and Kansas) from 1990 to 2014, the averages …

Experimental Assessment Of Predation Risk For Juvenile Green Sturgeon, Acipenser Medirostris, By Two Predatory Fishes, S. Baird, A. E. Steel, D. E. Cocherell, Jamilynn B. Poletto, R. Follenfant, N. A. Fangue

School of Natural Resources: Faculty Publications

No abstract provided.

Pesticide Application Practices And Knowledge Among Small-Scale Local Rice Growers And Communities In Rwanda: A Cross-Sectional Study, Benjamin Ndayambaje, Hellen Amuguni, Jeanne Coffin-Schmitt, Nancy Sibo, Martin Ntawubizi, Elizabeth Vanwormer

School of Natural Resources: Faculty Publications

Background: Agriculture contributes a third of Rwanda’s GDP and is the main source of income for rural households, with 80% of the total population involved in crop and/or livestock production. The Government of Rwanda established the Muvumba rice project in 2011 amidst a policy shift towards rice as a national staple crop. However, the indiscriminate use of pesticides by local, low-income rice growers has raised concerns about potential human, animal and ecosystem health impacts as pesticide distribution and application are not strictly regulated. Although pesticide use can directly influence farmer health and ecosystems, little is known about small-scale farmers’ pesticide …

A Pilot Qualitative Case Study Of Agricultural And Natural Resources Scientists’ Twitter Usage For Engaging Public Audiences, Jaime Loizzo, Catherine Jones, Abby Steffen

School of Natural Resources: Faculty Publications

Scientists are frequently asked to broadly share their expertise and research with a variety of audiences, beyond typical academic circles in their home disciplines. That could include developing community engagement programs, school outreach, leveraging online social networks, and other activities. The purpose of this study was to examine U.S. agricultural and natural resources (ANR) scientists’ typical science communication channels, their experiences utilizing Twitter for sharing their knowledge, research, and engaging in online public science discussion. Diffusion of Innovations theory and the model of science in-reach versus outreach guided this study. Researchers used a qualitative case study design. Data collection included …

A Methodology For Flash Drought Identification: Application Of Flash Drought Frequency Across The United Statesjordan, Jordan I. Christian, Jeffrey B. Basara, Jason A. Otkin, Eric D. Hunt, Ryann A. Wakefield, Paul Flanagan, Xiangming Xiao

School of Natural Resources: Faculty Publications

With the increasing use of the term ‘‘flash drought’’ within the scientific community, Otkin et al. provide a general definition that identifies flash droughts based on their unusually rapid rate of intensi- fication. This study presents an objective percentile-based methodology that builds upon that work by identifying flash droughts using standardized evaporative stress ratio (SESR) values and changes in SESR over some period of time. Four criteria are specified to identify flash droughts: two that emphasize the vegetative impacts of flash drought and two that focus on the rapid rate of intensification. The method- ology was applied to the North …

Evaluating The Efficacy Of The Rodenatortm (Propane-Oxygen Device) For Control Of Black-Tailed Prairie Dogs In Montana, Stephen M. Vantassel

School of Natural Resources: Faculty Publications

Black-tailed prairie dogs’ feeding and burrowing behavior is a significant economic nuisance to agricultural producers. We tested the RodenatorTM on two portions of an isolated prairie dog town in Lewis and Clark County, Montana to determine how effective it was in reducing prairie dog numbers. Though other studies have been done using propane-oxygen devices, our study employed updated application techniques and an aggressive hole closing procedure to reduce the likelihood of false failures. In the southern area, we treated 53 burrows for 30 seconds with oxygen set at 40 psi and propane at 45 psi. In the northern area, we …

A Methodology For Flash Drought Identification: Application Of Flash Drought Frequency Across The United States, Jordan I. Christian, Jeffery B. Basara, Jason A. Otkin, Eric D. Hunt, Ryann A. Wakefield, Paul X. Flanagan, Xiangming Xiao

School of Natural Resources: Faculty Publications

With the increasing use of the term ‘‘flash drought’’ within the scientific community, Otkin et al. provide a general definition that identifies flash droughts based on their unusually rapid rate of intensification. This study presents an objective percentile-based methodology that builds upon that work by identifying flash droughts using standardized evaporative stress ratio (SESR) values and changes in SESR over some period of time. Four criteria are specified to identify flash droughts: two that emphasize the vegetative impacts of flash drought and two that focus on the rapid rate of intensification. The methodology was applied to the North American Regional …

An Information Theory-Based Approach To Assessing Spatial Patterns In Complex Systems, Tarsha Eason, Wen Ching-Chuang, Shana Sundstrom, Heriberto Cabezas

School of Natural Resources: Faculty Publications

Given the intensity and frequency of environmental change, the linked and cross-scale nature of social-ecological systems, and the proliferation of big data, methods that can help synthesize complex system behavior over a geographical area are of great value. Fisher information evaluates order in data and has been established as a robust and effective tool for capturing changes in system dynamics, including the detection of regimes and regime shifts. The methods developed to compute Fisher information can accommodate multivariate data of various types and requires no a priori decisions about system drivers, making it a unique and powerful tool. However, the …

Variation In White-Tailed Deer Antler Size: The Effects Of Age, Landscape Composition, And Physiographic Province, Kathleen B. Quebedeaux, Andrew R. Little, Nathan P. Nibbelink, Gino J. D'Angelo, Charlie H. Killmaster, Karl V. Miller

School of Natural Resources: Faculty Publications

Spatial variation in landscape composition can influence phenotypic expression in wildlife species and can improve management efforts to express certain phenotypic traits. We evaluated the influence of age, landscape composition, and physiographic province on white-tailed deer (Odocoileus virginianus) antler characteristics using data from 16,622 male deer (age range: 1.5–3.5+ years old) harvested between 1997–2016 across five physiographic provinces in Georgia. Age and physiographic province influenced antler size index (ASI; P < 0.001). ASI of yearling males was greatest (- x = 53.37; SE = 0.39) in the Upper Coastal Plain and least (- x = 46.23; SE = 0.51) in the Lower Coastal Plain physiographic province. Given the differences in ASI among physiographic provinces, we evaluated how landscape composition within each physiographic province influenced ASI of 7,325 yearling (1.5-year-old) males. Yearling ASI was positively related to increasing coverage of cultivated crops and suburban-urban areas (e.g., parks, small housing developments). Conversely, evergreen and deciduous forested cover consistently had a negative effect on ASI, except in the Ridge and Valley physiographic province where evergreen was positively related to ASI. Wildlife managers and hunters should recognize the effects of age, landscape composition, and physiographic province when setting antler size expectations.

Variation In White-Tailed Deer Antler Size: The Effects Of Age, Landscape Composition, And Physiographic Province., K. B. Quebedeaux, Andrew R. Little, N. P. Nibbelink, G. J. D'Angelo, C. H. Killmaster, K. V. Miller

School of Natural Resources: Faculty Publications

Spatial variation in landscape composition can influence phenotypic expression in wildlife species and can improve management efforts to express certain phenotypic traits. We evaluated the influence of age, landscape composition, and physiographic province on white-tailed deer (Odocoileus virginianus) antler characteristics using data from 16,622 male deer (age range: 1.5–3.5+ years old) harvested between 1997–2016 across five physiographic provinces in Georgia. Age and physiographic province influenced antler size index (ASI; P < 0.001). ASI of yearling males was greatest (- x = 53.37; SE = 0.39) in the Upper Coastal Plain and least (- x = 46.23; SE = 0.51) in the Lower Coastal Plain physiographic province. Given the differences in ASI among physiographic provinces, we evaluated how landscape composition within each physiographic province influenced ASI of 7,325 yearling (1.5-year-old) males. Yearling ASI was positively related to increasing coverage of cultivated crops and suburban-urban areas (e.g., parks, small housing developments). Conversely, evergreen and deciduous forested cover consistently had a negative effect on ASI, except in the Ridge and Valley physiographic province where evergreen was positively related to ASI. Wildlife managers and hunters should recognize the effects of age, landscape composition, and physiographic province when setting antler size expectations.

Environmental Controls On The Seasonal Variation In Gas Exchange And Water Balance In A Near-Coastal Mediterranean Pinus Halepensis Forest, Mariangela N. Fotelli, Evangelia Korakaki, Spyridon A. Paparrizos, Kalliopi Radoglou, Tala Awada, Andreas Matzarakis

School of Natural Resources: Faculty Publications

No abstract provided.

Tree-Ring Stable Isotopes Show Different Ecophysiological Strategies In Native And Invasive Woody Species Of A Semi-Arid Riparian Ecosystem In The Great Plains Of The United States, Tala Awada, Kristen Skolaut, Giovanna Battipaglia, Matthias Saurer, Diego A. Riveros-Iregui, Adam Schapaugh, Julie Huddle, Xinhua Zhou, Derrell Martin, Paolo Cherubini

School of Natural Resources: Faculty Publications

No abstract provided.

Nu-Spidercam: A Large-Scale, Cable-Driven, Integrated Sensing And Robotic System For Advanced Phenotyping, Remote Sensing, And Agronomic Research, Geng Bai, Yufeng Ge, David Scoby, Bryan Leavitt, Vincent Stoerger, Norbert Kirchgessner, Suat Irkmak, George Graef, James Schnable, Tala Awada

School of Natural Resources: Faculty Publications

No abstract provided.

Leveraging Image Analysis For High-Throughput Plant Phenotyping, Sruti Das Choudhury, Ashok Samal, Tala Awada

School of Natural Resources: Faculty Publications

No abstract provided.

Comment On "Derivation Of A Sigmoid Generalized Complementary Function For Evaporation With Physical Constraints" By S. Han And F. Tian, Jozsef Szilagyi, Richard D. Crago

School of Natural Resources: Faculty Publications

No abstract provided.

National Survey Of Geoscience Teaching Practices 2016: Current Trends In Geoscience Instruction Of Scientific Modeling And Systems Thinking, Diane Lally, Cory T. Forbes, Karen S. Mcneal, Nicholas A. Soltis

School of Natural Resources: Faculty Publications

No abstract provided.

Empirical Methods For Remote Sensing Of Nitrogen In Drylands May Lead To Unreliable Interpretation Of Ecosystem Function, Hamid Dashti, Nancy F. Glenn, Susan Ustin, Jessica J. Mitchell, Yi Qi, Nayani T. Ilangakoon, Alejandro N. Flores, Jose Luis Silvan-Cardenas, Kaiguang Zhao, Lucas P. Spaete, Marie-Anne De Graaff

School of Natural Resources: Faculty Publications

No abstract provided.