Life Sciences Commons^™

Population Genetics Of Cownose Rays, Rhinoptera Spp. In The Western Atlantic, Helen Weber

Master's Theses

Using molecular tools (e.g., the NADH subunit II mitochondrial gene), this study was the first to document the Brazilian cownose ray, Rhinoptera brasiliensis, within the northwestern Atlantic (NWA), and was the first study to examine population structure in R. brasiliensis within the NWA or northern Gulf of Mexico (GMX), revealing novel insights into the population biology of the animal and extending its range by nearly 1,500 km. This study also examined the sympatrically occurring American cownose ray, R. bonasus, and found population structure between the NWA and the GMX and the NWA and the southwestern Atlantic (SWA). High …

A Modern Two-Layer Hypothesis Helps Resolve The ‘Savanna Problem’, Andrew Kulmatiski, Karen H. Beard

Wildland Resources Faculty Publications

For over a century, deep roots have been assumed to allow trees to avoid competition with grasses (i.e., the two-layer hypothesis). Yet, in part because it remains difficult to measure water uptake in the field, there has been a shift in savanna ecology away from the two-layer hypothesis and towards alternative explanations of tree-grass coexistence. Here, we combine hydrologic tracer experiments and soil water flow models to demonstrate how the distribution of active roots affects water uptake across a range of savanna conditions. Grass roots were shallower and provided pre-emptive access to enough soil water to allow nearly continuous grass …

Toward A Standard Formal Semantic Representation Of The Model Card Report, Xiaoqian Jiang, Fang Li, Evan Yu, Cui Tao

Faculty, Staff and Student Publications

BACKGROUND: Model card reports aim to provide informative and transparent description of machine learning models to stakeholders. This report document is of interest to the National Institutes of Health's Bridge2AI initiative to address the FAIR challenges with artificial intelligence-based machine learning models for biomedical research. We present our early undertaking in developing an ontology for capturing the conceptual-level information embedded in model card reports.

RESULTS: Sourcing from existing ontologies and developing the core framework, we generated the Model Card Report Ontology. Our development efforts yielded an OWL2-based artifact that represents and formalizes model card report information. The current release of …

Developing A Customised Note By Note Prototype Recipe Which Can Be 3d Printed, Roisin Burke, Pauline Danaher

Articles

Note by Note (NbN) cooking and 3D food printing individually and in combination allow for the creation of customized foods. A NbN recipe was developed and printed using a Procusini 3.0, 3D food printer. The recipe was adapted from a commercial powdered pastry dough recipe, to create two versions of a prototype food, containing in each case a different plant-based protein, i.e., soya (Glycine max L.) or hemp (Cannabis sativa). The printed foods were identical in shape and had a crisp consistency following cooking. They had different colours and contained different proteins in the amounts of 10.3 % of soya …

Toward A Standard Formal Semantic Representation Of The Model Card Report, Xiaoqian Jiang, Fang Li, Evan Yu, Cui Tao

Faculty, Staff and Student Publications

BACKGROUND: Model card reports aim to provide informative and transparent description of machine learning models to stakeholders. This report document is of interest to the National Institutes of Health's Bridge2AI initiative to address the FAIR challenges with artificial intelligence-based machine learning models for biomedical research. We present our early undertaking in developing an ontology for capturing the conceptual-level information embedded in model card reports.

RESULTS: Sourcing from existing ontologies and developing the core framework, we generated the Model Card Report Ontology. Our development efforts yielded an OWL2-based artifact that represents and formalizes model card report information. The current release of …

Post-Embryonic Phase Transitions Mediated By Polycomb Repressive Complexes In Plants, Valerie Hinsch, Samuel Adkins, Darren Manuela, Mingli Xu

Faculty Publications

Correct timing of developmental phase transitions is critical for the survival and fitness of plants. Developmental phase transitions in plants are partially promoted by controlling relevant genes into active or repressive status. Polycomb Repressive Complex1 (PRC1) and PRC2, originally identified in Drosophila, are essential in initiating and/or maintaining genes in repressive status to mediate developmental phase transitions. Our review summarizes mechanisms in which the embryo-to-seedling transition, the juvenile-to-adult transition, and vegetative-to-reproductive transition in plants are mediated by PRC1 and PRC2, and suggests that PRC1 could act either before or after PRC2, or that they could function independently of each other. …

Short-Term Effects Of Repeated-Sprint Training On Vertical Jump Ability And Aerobic Fitness In Collegiate Volleyball Players During Pre-Season, Petrus Gantois, Gilmário Ricarte Batista, Leonardo Sousa Fortes, Arnaldo Luís Mortatti, Matheus Dantas, Daniel Gomes Da Silva Machado, Breno Guilherme De Araújo Ticoco Cabral

International Journal of Exercise Science

International Journal of Exercise Science 15(6): 1040-1051, 2022. The aim of this study was to assess the effect of repeated-sprint training (RST) on vertical jump ability and aerobic power in college volleyball players. Nineteen male volleyball players, aged between 18-24 years, were randomized into the RST group (RST; n = 10) and control group (CG; n = 9). The RST included 2-3 sets of 6x30m all-out sprints, twice per week, in addition to the regular training routine. The control group performed only the regular volleyball training sessions (i.e. mainly of technical-tactical drills). All players performed a maximal graded treadmill test, …

Mortality Prediction Analysis Among Covid-19 Inpatients Using Clinical Variables And Deep Learning Chest Radiography Imaging Features., Xuan V Nguyen, Engin Dikici, Sema Candemir, Robyn L Ball, Luciano M Prevedello

Faculty Research 2022

The emergence of the COVID-19 pandemic over a relatively brief interval illustrates the need for rapid data-driven approaches to facilitate clinical decision making. We examined a machine learning process to predict inpatient mortality among COVID-19 patients using clinical and chest radiographic data. Modeling was performed with a de-identified dataset of encounters prior to widespread vaccine availability. Non-imaging predictors included demographics, pre-admission clinical history, and past medical history variables. Imaging features were extracted from chest radiographs by applying a deep convolutional neural network with transfer learning. A multi-layer perceptron combining 64 deep learning features from chest radiographs with 98 patient clinical …

Assessing The Effects Of Elevation On The Peaks Of Otter Salamander (Plethodon Hubrichti) Using Body Condition Index, Norman Reichenbach, Timothy R. Brophy, Hannah Suber, Elisabeth Russell, Hannah Kinsley, Liam Cusack, Cetia Dawson, Savannah Dunn, Olivia De Araujo

Faculty Publications and Presentations

The Peaks of Otter Salamander (Plethodon hubrichti; POS) is a montane species found at elevations above 442 m within a 117 km2 area of the Blue Ridge Mountains in central Virginia. In allopatric areas (areas without the Eastern Red-backed Salamander, P. cinereus, a known competitor), POS body condition was hypothesized to decline both above and below some optimal elevation. Decreased condition at lower elevations would most likely be due to increased temperatures and lower relative humidities, which may adversely affect the ability of salamanders to forage effectively on vegetation due to desiccation risk. Decreased condition at elevations above …

Comparing The Performance Of Cooperative Plans For Equity Accumulation And Retirement, Jeffrey S. Royer

Cornhusker Economics

Equity allocated to members plays a crucial role in financing agricultural cooperatives. Although retained earnings not allocated to members have become an increasingly importantsource of equity in recent years, U.S. Department of Agriculture (USDA) data show thatallocated equity still accounted for 55.5 percent of the $47.5 billion in total equity held in U.S.cooperatives in 2020. [1] Allocated member equity differs from unallocated equity fromretained earnings in that it is owned by individual members and there is an expectation thatit will be redeemed in cash when it is eventually replaced by newer allocations. A recent study has examined the comparative performance …

Peripheral Artery Disease Affects The Function Of The Legs Of Claudicating Patients In A Diffuse Manner Irrespective Of The Segment Of The Arterial Tree Primarily Involved, Todd Leutzinger, Panagiotis Koutakis, Matthew A. Fuglestad, Hafizur Rahman, Holly Despiegelaere, Mahdi Hassan, Molly Schieber, Jason Johanning, Nikolas Stergiou, G. Matthew Longo, George P. Casale, Sara A. Myers, Iraklis Pipinos

Journal Articles

Different levels of arterial occlusive disease (aortoiliac, femoropopliteal, multi-level disease) can produce claudication symptoms in different leg muscle groups (buttocks, thighs, calves) in patients with peripheral artery disease (PAD). We tested the hypothesis that different locations of occlusive disease uniquely affect the muscles of PAD legs and produce distinctive patterns in the way claudicating patients walk. Ninety-seven PAD patients and 35 healthy controls were recruited. PAD patients were categorized to aortoiliac, femoropopliteal and multi-level disease groups using computerized tomographic angiography. Subjects performed walking trials both pain-free and during claudication pain and joint kinematics, kinetics, and spatiotemporal parameters were calculated to …

Abundance, Site-Fidelity, And Association Patterns Of Coastal Bottlenose Dolphins (Tursiops Truncatus) Off Southeast Florida, Graysen D. Boehning

All HCAS Student Capstones, Theses, and Dissertations

The coastal bottlenose dolphin is well studied throughout its natural range, however, most of the study areas comprised wide, well-protected habitats such as bays and estuaries, and not narrow coastal sandbanks. This study identifies a residential group of coastal bottlenose dolphins utilizing the narrow sandbanks within the Northwestern Atlantic waters off the coast of Palm Beach County, Florida, USA. From 2014-2020, 313 boat surveys were conducted, and 585 individual dolphins were identified using photo-ID. Twenty-four animals were determined to be full-time and 66 animals were determined to be part-time residents. Full-time and part-time residents associated in three social tribes, with …

Bioaccumulation Of As, Cd, Cr, Cu, Pb, Zn In Ambrosia Artemisiifolia L. In The Polluted Area By Enterprise For The Production And Processing Of Batteries, Ryzhenko Nataliia, El Amrani Abdelhak, Michelle Giltrap, Furong Tian, Volodymyr Laptev

Articles

In this paper, the concentration of As, Cd, Cr, Cu, Pb, Zn was investigated in soil and Ambrosia artemisiifolia L. sampling from polluted cite near the enterprises for the production and processing of batteries in the city of Dnipro in Ukraine. The obtained results of the study provided to assess plants regarding bio-monitoring and phytoremediation. Although Ambrosia artemisiifolia L. is a weed that causes serious allergic reactions in humans, this species can also have a high bioaccumulative capacity regarding metals. The metals’ concentration in roots was scientifically higher than in inflorescence part. Zn and Cu had the highest …

A Dual-Function Gene In Zea Mays That Encodes Two Β-Amylase Proteins With Different Cellular Locations And Functions, Kenan Ozcan

Masters Theses, 2020-current

A noncanonical β-amylase7 (BAM7) gene found in some basal angiosperms and some monocots, including corn, appears to encode two functionally distinct proteins. Phylogenetic evidence suggests that BAM7 originated from a fusion event that combined a BZR1-like DNA-binding domain to the 5’ end of BAM2 about 400 million years ago (mya). In Arabidopsis thaliana (At), AtBAM7 is a catalytically-inactive transcription factor found in the nucleus and AtBAM2 is a catalytically-active, tetrameric starch hydrolase found in the chloroplast. These proteins are encoded on different chromosomes. The corn (Zea mays, Zm) genome does not contain a BAM2 gene, however …

Consequences Of Gulf Of Mexico Estuarine Tropical Cyclone Disturbance Regimes For Fish Assemblage Dynamics Conditionally Depend On Life-History Traits And Niche Characteristics, Stephen Edward Potts

LSU Doctoral Dissertations

Tropical cyclones (TC) are intense, localized disturbances that can potentially cause extensive damage to ecosystems. This dissertation is motivated by a need for interdisciplinary study of TC-ecosystem dynamics with applications to ecology, geography, and analytical methodology. I explore concept linkages between TC dynamics and ecosystems to characterize TC-ecosystem relationships as ecological disturbance regimes. This dissertation tests hypotheses and relationships of TC effects on estuarine fish assemblages in the north-western Gulf of Mexico. I explore concepts in TC-ecosystem relationships to link biotic dynamics with physical disturbance.

In Chapter 2, I compared spatial performance of generalized linear models (GLMs) and generalized additive …

Gut Bacterial Isoamylamine Promotes Age-Related Cognitive Dysfunction By Promoting Microglial Cell Death, Yun Teng, Jingyao Mu, Fangyi Xu, Xiangcheng Zhang, Mukesh K Sriwastva, Xiaohong Li, Kumaran Sundaram, Xin Hu, Lifeng Zhang, Juw Won Park, Jae Yeon Hwang, Eric C Rouchka, Xiang Zhang, Jun Yan, Michael L Merchant, Huang-Ge Zhang

Faculty, Staff and Student Publications

The intestinal microbiome releases a plethora of small molecules. Here, we show that the Ruminococcaceae metabolite isoamylamine (IAA) is enriched in aged mice and elderly people, whereas Ruminococcaceae phages, belonging to the Myoviridae family, are reduced. Young mice orally administered IAA show cognitive decline, whereas Myoviridae phage administration reduces IAA levels. Mechanistically, IAA promotes apoptosis of microglial cells by recruiting the transcriptional regulator p53 to the S100A8 promoter region. Specifically, IAA recognizes and binds the S100A8 promoter region to facilitate the unwinding of its self-complementary hairpin structure, thereby subsequently enabling p53 to access the S100A8 promoter and enhance S100A8 expression. …

Targeting Paleovalley-Related Ferricrete Units In Yilgarn Craton Using High-Resolution Aeromagnetic Data And Spatial Machine Learning, Hassan Talebi, Jelena Markov, Walid Salama, Alex Otto, Vasek Metelka, Ravi Anand, Dave Cole

Research outputs 2022 to 2026

The ferricrete units (Fe oxide cemented colluvial-alluvial sediment) of the Yilgarn Craton in Western Australia formed during the humid tropical and sub-tropical climates of the Cenozoic. Ferricretes are generally developed on long-lived paleodrainage systems and are products of the ferruginisation of detritus provided by the continuous erosion of upslopes. These iron-rich accumulations can become Au-enriched, as is the case in several locations previously discovered in the Yilgarn Craton; many of these host economic secondary gold deposits (e.g., Moolart Well, Mt Gibson, and Bulchina), typically occurring downslope of low saprolite hills and near paleovalleys (i.e., inset-valleys). Inset-valleys are a common paleotopographic …

A Research Agenda To Support The Development And Implementation Of Genomics-Based Clinical Informatics Tools And Resources., Ken Wiley, Laura Findley, Madison Goldrich, Tejinder K Rakhra-Burris, Ana Stevens, Pamela Williams, Carol J Bult, Rex Chisholm, Patricia Deverka, Geoffrey S Ginsburg, Eric D Green, Gail Jarvik, George A Mensah, Erin Ramos, Mary V Relling, Dan M Roden, Robb Rowley, Gil Alterovitz, Samuel Aronson, Lisa Bastarache, James J Cimino, Erin L Crowgey, Guilherme Del Fiol, Robert R Freimuth, Mark A Hoffman, Janina Jeff, Kevin Johnson, Kensaku Kawamoto, Subha Madhavan, Eneida A Mendonca, Lucila Ohno-Machado, Siddharth Pratap, Casey Overby Taylor, Marylyn D Ritchie, Nephi Walton, Chunhua Weng, Teresa Zayas-Cabán, Teri A Manolio, Marc S Williams

Faculty Research 2022

OBJECTIVE: The Genomic Medicine Working Group of the National Advisory Council for Human Genome Research virtually hosted its 13th genomic medicine meeting titled "Developing a Clinical Genomic Informatics Research Agenda". The meeting's goal was to articulate a research strategy to develop Genomics-based Clinical Informatics Tools and Resources (GCIT) to improve the detection, treatment, and reporting of genetic disorders in clinical settings.

MATERIALS AND METHODS: Experts from government agencies, the private sector, and academia in genomic medicine and clinical informatics were invited to address the meeting's goals. Invitees were also asked to complete a survey to assess important considerations needed to …

Ci Asteroid Regolith As An In Situ Plant Growth Medium For Space Crop Production, Steven J. Russell, Sherry Fieber-Beyer, Kathryn A. Yurkonis

Biology Faculty Publications

Human expansion into the solar system is currently at the forefront of space research. For our astronauts to survive, they will need to be fed a healthy and nutritious diet on a consistent basis. Right now, our current method of feeding astronauts consists of resupplied prepackaged food from Earth, which is unsustainable for long-term missions. Using planetary resources via in situ resource utilization to grow crops is the next step toward sustainability in space. Asteroids are an abundant space resource and should not be overlooked when considering crewed missions. In particular, the primordial CI carbonaceous asteroids are of interest because …

Creating A Shared Musical Interpretation: Changes In Coordination Dynamics While Learning Unfamiliar Music Together, Emily A. Wood, Andrew Chang, Dan Bosnyak, Lucas Klein, Elger Baraku, Dobromir Dotov, Laurel Trainor

Journal Articles

The ability to coordinate with others is fundamental for humans to achieve shared goals. Often, harmonious interpersonal coordination requires learning, such as ensemble musicians rehearing together to synchronize their low-level timing and high-level aesthetic musical expressions. We investigated how the coordination dynamics of a professional string quartet changed as they learned unfamiliar pieces together across eight trials. During all trials, we recorded each musician's body sway motion data, and quantified the group's body sway similarity (cross-correlation) and information flow (Granger causality) on each trial. In line with our hypothesis, group similarity increased, while group information flow decreased significantly across trials. …

Hip Torque Is A Mechanistic Link Between Sprint Acceleration And Maximum Velocity Performance: A Theoretical Perspective, Kenneth P. Clark, Laurence J. Ryan

Kinesiology Faculty Publications

Sprinting performance is critical for a variety of sports and competitive activities. Prior research has demonstrated correlations between the limits of initial acceleration and maximum velocity for athletes of different sprinting abilities. Our perspective is that hip torque is a mechanistic link between these performance limits. A theoretical framework is presented here that provides estimates of sprint acceleration capability based on thigh angular acceleration and hip torque during the swing phase while running at maximum velocity. Performance limits were calculated using basic anthropometric values (body mass and leg length) and maximum velocity kinematic values (contact time, thigh range of motion, …

Developmental Competence Of Oocytes Derived From Seasonally Anovulatory Mares Treated With Estradiol And Sulpiride, Michelle O. Vetter

LSU Master's Theses

Over the course of two years (2021-2022), two experiments were conducted during the nonbreeding seasons to evaluate the in vitro developmental potential of oocytes derived from seasonally anovulatory mares treated with ECP-sulpiride. The objective of experiments 1 and 2 were to compare pooled recovery and maturation rates of oocytes from mares treated with estradiol cypionate (ECP) and sulpiride with oocytes collected from naturally transitional mares (controls). Cleavage rates of oocytes subjected to intracytoplasmic sperm injection (ICSI) were compared only in experiment 2. In experiments 1 and 2, a total of 36 light horse and pony-cross anovulatory mares were used. Treatment …

Synthesis Of Boron-Doped Zinc Oxide Nanosheets By Using Phyllanthus Emblica Leaf Extract: A Sustainable Environmental Applications, Awais Khalid, Pervaiz Ahmad, Saleh Muhammad, Abdulhameed Khan, Mayeen Uddin Khandaker, Md Mottahir Alam, Mohd Asim, Israf Ud Din, Jibran Iqbal, Ibad Ur Rehman, Zohaib Razzaq, Sivakumar Pandian, Rohit Sharma, Talha Bin Emran, M. I. Sayyed, Saad Aldawood, Abdelmoneim Sulieman

All Works

The use of Phyllanthus emblica (gooseberry) leaf extract to synthesize Boron-doped zinc oxide nanosheets (B-doped ZnO-NSs) is deliberated in this article. Scanning electron microscopy (SEM) shows a network of synthesized nanosheets randomly aligned side by side in a B-doped ZnO (15 wt% B) sample. The thickness of B-doped ZnO-NSs is in the range of 20–80 nm. B-doped ZnO-NSs were tested against both gram-positive and gram-negative bacterial strains including Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia, and Escherichia coli. Against gram-negative bacterium (K. pneumonia and E. coli), B-doped ZnO displays enhanced antibacterial activity with 26 and 24 mm of inhibition zone, respectively. …

Compositional And Metabolic Responses Of Autotrophic Microbial Community To Salinity In Lacustrine Environments, Yun Fang, Jun Liu, Jian Yang, Geng Wu, Zhengshuang Hua, Hailiang Dong, Brian P. Hedlund, Brett J. Baker, Hongchen Jiang

Life Sciences Faculty Research

The compositional and physiological responses of autotrophic microbiotas to salinity in lakes remain unclear. In this study, the community composition and carbon fixation pathways of autotrophic microorganisms in lacustrine sediments with a salinity gradient (82.6 g/L to 0.54 g/L) were investigated by using metagenomic analysis. A total of 117 metagenome-assembled genomes (MAGs) with carbon fixation potentially belonging to 20 phyla were obtained. The abundance of these potential autotrophs increased significantly with decreasing salinity, and the variation of sediment autotrophic microbial communities was mainly affected by salinity, pH, and total organic carbon. Notably, along the decreasing salinity gradient, the dominant lineage …

Evolution Of Freshwater Fishes In The Northern Neotropics, Diego Elias

LSU Doctoral Dissertations

The northern Neotropics (NN) represents one of the most geologically-complex regions on the planet, composed of island-like geological blocks that have undergone multiple episodes of isolation and connectivity at various geological times. The riverscapes of the NN harbor a unique assemblage of freshwater fishes. In contrast to the freshwaters systems of South America, which are dominated by ostariophysan lineages, the aquatic systems of the NN are dominated by lineages of two families: Cichlidae (cichlids) and Poeciliidae (livebearers). It has been suggested that the geologically complex nature of the region allowed ancestors of cichlids and livebearers to colonize and radiate within …

Beyond Efficiency: Surface Electromyography Enables Further Insights Into The Surgical Movements Of Urologists, Rahul Soangra, Pengbo Jiang, Daniel Haik, Perry Xu, Andrew Brevik, Akhil Peta, Shlomi Tapiero, Jaime Landman, Emmanuel John, Ralph V. Clayman

Physical Therapy Faculty Articles and Research

Introduction: Surgical skill evaluation while performing minimally invasive surgeries is a highly complex task. It is important to objectively assess an individual's technical skills throughout surgical training to monitor progress and to intervene when skills are not commensurate with the year of training. The miniaturization of wireless wearable platforms integrated with sensor technology has made it possible to noninvasively assess muscle activations and movement variability during performance of minimally invasive surgical tasks. Our objective was to use electromyography (EMG) to deconstruct the motions of a surgeon during robotic suturing (RS) and distinguish quantifiable movements that characterize the skill of an …

Treatment-Free Remission After Ceasing Venetoclax-Based Therapy In Patients With Acute Myeloid Leukemia, Chong Chyn Chua, Danielle Hammond, Andrew Kent, Ing Soo Tiong, Marina Y Konopleva, Courtney D Dinardo

Faculty, Staff and Student Publications

The clinical benefit of adding venetoclax (VEN) to hypomethylating agents or low-dose cytarabine in older and/or unfit patients with newly diagnosed acute myeloid leukemia (AML) has been confirmed in phase 3 studies. With the increased uptake of VEN-based therapies for patients with AML, a pertinent question is whether treatment can be safely ceased among patients who have achieved sustained remission. We hypothesized that a proportion of patients opting to cease therapy may benefit from a treatment-free remission (TFR) period without indefinite treatment. We report the retrospective outcomes of 29 patients in remission for a minimum of 12 months on VEN-based …

High-Sensitivity Next-Generation Sequencing Mrd Assessment In All Identifies Patients At Very Low Risk Of Relapse, Nicholas J Short, Hagop Kantarjian, Farhad Ravandi, Marina Konopleva, Nitin Jain, Keyur P Patel, Tapan M Kadia, Sa Wang, Jeffrey L Jorgensen, Joseph D Khoury, Musa Yilmaz, Partow Kebriaei, Koichi Takahashi, Guillermo Garcia-Manero, Naval Daver, Sean M Post, Xuelin Huang, Steven M Kornblau, Sara Pelletier, Wilmer Flores, Jairo Matthews, Rebecca Garris, Elias Jabbour

Faculty, Staff and Student Publications

Measurable residual disease (MRD) is highly prognostic for relapse and overall survival (OS) in acute lymphoblastic leukemia (ALL), although many patients with apparent "MRD negativity" by standard assays still relapse. We evaluated the clinical impact of a highly sensitive next-generation sequencing (NGS) MRD assay in 74 adults with ALL undergoing frontline therapy. Among remission samples that were MRD negative by multiparameter flow cytometry (MFC), 46% were MRD+ by the NGS assay. After 1 cycle of induction chemotherapy, MRD negativity by MFC at a sensitivity of 1 × 10-4 and NGS at a sensitivity of 1 × 10-6 was achieved in …

Recreational Caving Impacts Of Visitors In A High-Altitude Cave In Bolivian Andes: Main Effects On Microhabitat Structure And Faunal Distribution, Lais Furtado Oliveira, Rodrigo L. Ferreira, Jaime Iván Rodríguez Fernández, Marconi Souza Silva

International Journal of Speleology

The cave’s physical environment can be affected by tourism activities but only a few studies evaluated how recreational use may affect the cave fauna, mainly in caves with a low number of visitors per year. To test the hypothesis that recreational use led to changes in habitat structure and invertebrate diversity, distinct scales along a cave were analyzed. Distinct areas with and without human visitation were analyzed and transects (10 x 3 m) and quadrats (1 x 1 m) were used to access the invertebrate communities and environmental traits. Thirty-two invertebrate species were recorded, among which six are troglobitic. The …

Relating Plant Community Structure To Carbon Dynamics In Semiarid Grasslands, Theodore D. Roper

Biology ETDs

Understanding how fine-scale changes in soil characteristics and plant community composition affect ecosystem functioning is key to predicting how biome shifts will affect regional and global carbon cycling. This is crucial in the dryland biomes of the US Southwest, projected to be one of the regions most affected by climate change. We examined fine-scale drivers of ecosystem function within two biomes – a Chihuahuan Desert grassland and Plains/Chihuahuan Desert ecotone – via long-term vegetation data, micrometeorological data, eddy covariance carbon flux measurements, and soil water and texture, finding that the ecotone site had over 30% higher soil water content, over …