Earth Sciences Commons^™

Protogynous Interval In Elephantgrass (Pennisetum Purpureum Schum.), A V. Pereira, R B. Barra, J C. Abreu, V De P. Freitas

IGC Proceedings (1977-2023)

A study was carried out to examine the protogyny duration in elephantgrass inflorescences. Nine accessions were selected, divided into three groups, according to early, intermediate or late flowering. From each cultivar, 10 panicles were sampled for evaluation. The criterion for estimating the duration of protogyny was the time interval (number of days) from the first visual detection of exserted stigmas up to the first visual appearance of open anthers (±5%). Duration of protogyny averaged 7.43±1.37 d, confirming that the species is protoginous. Late flowering accessions exhibited an average of 8.97 d for the duration of protogyny, which was significantly higher …

Evolution In Segregating Genotype Mixtures Of Subterranean Clover, P.G. H. Nichols, P S. Cocks

IGC Proceedings (1977-2023)

A complex segregating mixture of subterranean clover (Trifolium subterraneum L.), was sown in 1978 at Nabawa and Mt Barker, two contrasting sites in Western Australia. Seed harvested from both sites from 1980-1994 was grown out at Shenton Park in 1995, along with seed of the original mixture. Populations diverged markedly for mean days to first flowering (DFF) within three seasons. No further trends in mean DFF occurred in plants derived from the next 14 years, although standard deviation declined significantly in plants from Mt Barker. Between season differences in mean DFF were correlated with estimated growing season length at …

Prediction Of Seed Yield Of Festuca X Lolium Hybrids From The Nursery Mother Plants, C Mousset, L Hazard, M Ghesquiere

IGC Proceedings (1977-2023)

In order to develop commercial Festuca x Lolium hybrids, their seed production has to be improved. Seed yields of Festuca x Lolium progenies were assessed in dense plots. Prediction of those seed yields was based on the morphological observations done on spaced plants in the nursery of both mother plants and their progenies. The best prediction of the progeny seed yields is a linear regression on the stem density and the seed weight per inflorescence assessed on the mother plants.

Use Of Flow Cytometer In Breeding Festuca X Lolium Hybrids, M C. Kerlan, M Ghesquiere

IGC Proceedings (1977-2023)

Ploidy in various generic Lolium - Festuca progenies were assessed by flow cytometry and compared to conventional chromosome counting. In non-segregating triploid and tetraploid progenies, the cytometer estimated so accurately the level of plant ploidy that chromosomes counting would be no use. In segregant progenies, all the tetraploid plants according to the cytometer had effectively 28 chromosomes. Among the triploid and pentaploid plants detected by the cytometer, 40% of the plants were tetraploid. They represented only 29% of the progeny which must be counted. The flow cytometry can be used in routine interspecific breeding programmes. Conventional chromosome counting should be …

Persistency In Lolium X Festuca Hybrid Derivatives And Its Relationships With Flowering Traits, M Ghesquiere, C Mousset

IGC Proceedings (1977-2023)

Using amphiploid and backcrossed derivatives of Italian ryegrass x tall fescue hybrids, the paper emphasizes the interest of introgression vs amphiploidization in breeding for specific traits such as persistency or seed production from tall fescue or ryegrass resp. Persistency in amphiploid and Lolium-introgressed progenies were assessed in nursery together with variation of flowering traits. Persistency was found lower, on average, in introgressed progenies than in hybrid progenies but with enlarged variability within progeny suggesting possible advantageous rearrangements of fescue chromosomes. Although significantly associated, persistency in both populations was only very little affected by the variations in flowering traits such …

Field Evaluation Of Crown Rust In Annual Ryegrass Populations, G M. Prine

IGC Proceedings (1977-2023)

Crown rust (Puccinia coronata [Pers.] Cda.) is the most prevalent disease found on annual ryegrass (Lolium multiflorum L.) of the southeastern USA. Determination of crown rust resistance is difficult because of the erratic nature of infections at most locations. As crown rust is present at Gainesville, FL each year, a rust nursery was designed to evaluate rust resistance and susceptibility of annual ryegrass. Evaluation consists of periodic rust ratings of the seed crop and regrowth of part of each plot after cutting. Nursery results indicate the buildup of rust, including at the date of 90% heading (start of …

Selection Of Interspecific Hybrids Of Brachiaria-A Tropical Forage Grass, C B. Do Valle

IGC Proceedings (1977-2023)

The aim of the breeding program at the National Beef Cattle Research Center (CNPGC) of the Brazilian Corporation for Agricultural Research (EMBRAPA), is to produce vigorous apomictic hybrids with wide edaphic adaptation, good production and nutritive value combined with spittlebug (Homoptera:Cercopidea) resistance. Fiftysix superior hybrids were selected based on visual estimates of vigor, leafiness, tolerance to drought and natural spittlebug infestation in the field. These were characterized for mode of reproduction, spittlebug reaction under controlled conditions and for morphological diversity using nine selected traits. Multivariate analysis classified the population into seven groups where the hybrids were clearly intermediate in plant …

Mitochondrial Genome Polymorphism In Lolium Perenne, Y Shimamoto, Y Tominaga, M Sato, T Mikami

IGC Proceedings (1977-2023)

The restriction fragment length polymorphisms (RFLPs) of mitochondrial DNA (mtDNA) of perennial ryegrass (Lolium perenne L.) were investigated to elucidate the genetic relatedness among the 128 cultivars including diploid and tetraploid. Many patterns of RFLPs were observed and allowed assigning of the cultivars into the main eight haplotypes of mitochondrial genome relatedness. The American cultivars were classified into haplotype I and VIII which were remote at the mitochondrial genome from each other, the European ones were distributed to all haplotypes and the tetraploid ones were mostly assigned into the haplotype V. The assessment of mtDNA RFLPs may be a …

Inbreeding Of Some Populations In The Genus Agrostis L., Zorica Tomic, Gordana Surlan Momirovic, Dusica Delic, S Ostojic

IGC Proceedings (1977-2023)

This work presents some properties on produced inbred lines of the 5 best populations of 4 species of Agrostis for breeding purposes. The cultivars of forage grasses should meet a given aim for selection, which is the increasing dry matter and quality. The populations used in this research were the best ones for morphological and productive properties from a previous study. By the process of selfing there have been produced S1 offsprings which appeared to be quite superior in relation to open pollinated offspring from the mother plants. The obtained results were processed by multiple range regression analyses. According to …

The Effect Of Abscisic Acid On The Freezing Tolerance In Lolium Temulentum L., K Tase, H Fujii

IGC Proceedings (1977-2023)

This study was conducted to clarify the effect of abscisic acid (ABA) on the development of freezing tolerance in Lolium temulentum L. We compared the changes of freezing tolerance and endogenous ABA content by the ABA treatment with those by the hardening treatment. Exogenous ABA applications (7.5 x 10-5 M) increased freezing tolerance, but did not completely substitute for the hardening process. This treatment resulted in great increase in endogenous ABA content, as compared with the control or the hardening treatment. Since the relationship between endogenous ABA content and freezing tolerance was not parallel, it is considered that freezing tolerance …

Introduction Of Vegetative And Reproductive Characters Into Trifolium Repens By Interspecific Hybridisation, A H. Marshall, T P.T Michaelson-Yeates, M Meredith, D H. Hides

IGC Proceedings (1977-2023)

Interspecific hybridization between white clover (Trifolium repens L.) and ball clover (T.nigrescens) and Caucasian clover (T.ambiguum) is a means of improving the reproductive growth and persistency of T.repens. F1 hybrids between T.repens and T.nigrescens were produced without ovule culture and confirmed as true hybrids by chromosome counts, isoenzyme analysis and leaf markers. Their growth habit was generally intermediate between the two parents. After backcrossing to T.repens the BC1 and BC2 hybrids had more of the characteristics associated with T.repens though they retained some of the greater reproductive growth of …

Colchicine-Doubling Of Germinating Seedlings Of Interspecific Wildrye Hybrids, T A. Jones, D C. Nielson, H Jaussi

IGC Proceedings (1977-2023)

Colchicine has usually been applied to sterile clones of interspecific grass hybrids to restore fertility. However, when hybrids are partially fertile, colchicine can be applied to germinating seedlings. Four populations of Basin wildrye (Leymus cinereus) X beardless wildrye (L. triticoides) were treated with a 0.2% colchicine solution to double chromosome number from 4x=28 to 8x=56. Doubling percentage was 28, 33, 42, and 44% of all root-tips examined for the four populations. When plants without doubled sectors were discarded, doubling percentage increased to 56, 68, 78, and 78%. Plants with doubled sectors have been placed in crossing blocks …

Plants Reduced Nitrous Oxide Emissions From A Northern Great Plains Saline/Sodic Soil, Sharon A. Clay, Thandiwe Nleya, David E. Clay, Deepak Joshi, Dwarika Bhattarai, Shin-Yi Marzano, Bhanu Prakash Petla

Agronomy, Horticulture and Plant Science Faculty Publications

The slowly establishing salt-tolerant perennial grasses reduced nitrous oxide (N2 O- N) emissions from saline/sodic soil compared to barren areas. Other salt-tolerant species may accelerate vegetative establishment and reduce N 2 O-N emissions. In a greenhouse study, barley (Hordeum vulgare L.), Florida broadleaf mustard (Brassica juncea L.), and Kernza intermediate wheatgrass [Thinopyrum intermedium (Host) Barkworth & D. R. Dewey] were grown for 63 days to compare shoot biomass and chemical composition, N 2 O-N emissions, and the soil microbiome between saline/sodic and productive (non-salt impacted) soils. Emissions were measured six times daily from 1 to 22 and 42 to 63 …

Publications And Other Works By R. F. Diffendal, Jr., Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Articles
Chapters in Books
Books
Field Guides
Geologic Maps
Other Maps
Cover Photographs
Other Photographs
Newspaper and Other Articles
Test-Hole Logs
Television Programs
Geonotes
Abstracts
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Manuscripts Accepted (A), Submitted (S), or in Preparation (P)
Geologic Maps in Press
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Updated March 2024

Human-Wildlife Conflict And The Likelihood Of Reporting Losses In Nepal, Gita Bhushal, Bernabas Wolde, Pankaj Lal

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

All development indices are changing due to increased exploitation of nature and growing economies in developing countries. This situation may increase the intensity of conflict between humans and wild species, such as large carnivores. Despite the increasing intensity of human-wildlife conflicts and the existing compensation scheme that compensates for the loss, most losses to human-wildlife conflicts are not reported to authorities. Thus, this study was conducted in the Banke National Park of Nepal to explore possible factors influencing the propensity to report losses. All 197 surveyed participants reported suffering from crop raids by wild animals, and 80 respondents (40.60 %) …

High-Precision U-Pb Geochronology Links Magmatism In The Southwestern Laurentia Large Igneous Province And Midcontinent Rift, M. T. Mohr, M. D. Schmitz, N. L. Swanson-Hysell, K. E. Karlstrom, F. A. Macdonald, M. E. Holland, Y. Zhang, N. S. Anderson

Geosciences Faculty Publications and Presentations

The Southwestern Laurentia large igneous province (SWLLIP) comprises voluminous, widespread ca 1.1 Ga magmatism in the southwestern United States and northern Mexico. The timing and tempo of SWLLIP magmatism and its relationship to other late Mesoproterozoic igneous provinces have been unclear due to difficulties in dating mafic rocks at high precision. New precise U-Pb zircon dates for comagmatic felsic segregations within mafic rocks reveal distinct magmatic episodes at ca. 1098 Ma (represented by massive sills in Death Valley, California, the Grand Canyon, and central Arizona) and ca. 1083 Ma (represented by the Cardenas Basalts in the Grand Canyon and a …

Lower Bound On Preserved Flood Duration In Fluvial Bedform Stratigraphy (Experimental Dataset), Robert C. Mahon, Vamsi Ganti, Madeline M. Kelley, Debsmita Das, Victoria Sanchez, Giancarlo Portocarrero, Mayson Fredricks

Lower Bound on Preserved Flood Duration in Fluvial Bedform Stratigraphy (experimental dataset)

This data is collected to assess the role of hydrograph timescale relative to dune migration on the preservation of cross sets in the stratigraphic record. The data presented here are of dune evolution under steady-state conditions, as well as three hydrographs of the same magnitude but varying timescales.

Methodology:

We collected data from four experiments tracking bedform evolution in a 22-m-long, 0.56-m-wide, 0.9-m-deep flume at the University of New Orleans Dynamics of Sedimentation laboratory. We conducted an equilibrium experiment (discharge value 0.027 m3/s) and three flood experiments, which were characterized by a symmetrical flood wave. In all flood experiments, the …

Method For Calibrating An Arduino-Based Soil Moisture Sensor Using Van Genuchten’S Equation, Victorino A. Bato, John Osbert Alindogan

The Philippine Agricultural Scientist

Instructions on building a do-it-yourself soil moisture sensor using Arduino microcontrollers abound on the Internet. These do-it-yourself soil moisture sensors are favorite projects by both plant and microcontroller enthusiasts because the parts are affordable and the end product is functional. In the absence of proper calibration, these soil moisture sensors cannot generate usable information on the status of plant-available-water in the soil. This research demonstrates the calibration of an Arduino-based soil moisture sensor using the soil moisture characteristic curve of a clay loam soil. Van Genuchten’s model was used to generate an equation and various parameters specific to the soil. …

Stage And Discharge Prediction From Documentary Time-Lapse Imagery, Kenneth W. Chapman, Troy E. Gilmore, Mehrube Mehrubeoglu, Christian D. Chapman, Aaron R. Mittelstet, John E. Stranzl Jr.

Conservation and Survey Division: Faculty and Staff Publications

Imagery from fixed, ground-based cameras is rich in qualitative and quantitative information that can improve stream discharge monitoring. For instance, time-lapse imagery may be valuable for filling data gaps when sensors fail and/or during lapses in funding for monitoring programs. In this study, we used a large image archive (>40,000 images from 2012 to 2019) from a fixed, ground-based camera that is part of a documentary watershed imaging project (https://plattebasintimelapse.com/). Scalar image features were extracted from daylight images taken at one-hour intervals. The image features were fused with United States Geological Survey stage and discharge data as response variables …

New Geochemical And Geochronological Insights On Forearc Magmatism Across The Sanak-Baranof Belt, Southern Alaska: A Tale Of Two Belts, Adrian A. Wackett, Diane R. Smith, Cameron Davidson, John I. Garver

Earth and Environmental Geosciences Faculty Research

The Sanak- Baranof belt includes a series of near- trench plutons that intrude the outboard Chugach– Prince William terrane over ~2200 km along the southern Alaskan margin. We present new petrological, geochronological, and geochemical data for comagmatic microgranitoid enclaves and granitoid rocks from the Crawfish Inlet (ca. 53– 47 Ma) and Krestof Island (ca. 52 Ma) plutons on Baranof and Krestof Islands, as well as the Mount Stamy (ca. 51 Ma) and Mount Draper (ca. 54– 53 Ma) plutons and associated mafic rocks that intrude the Boundary block at Nunatak Fiord near Yakutat, Alaska, USA. These data suggest that intrusion …

Pcor Partnership Atlas, Wesley D. Peck, Kari Suedel, Kyle A. Glazewski, Kevin C. Connors, James A. Sorensen, Charles D. Gorecki, Brian P. Kalk, John A. Harju

EERC Maps and Infographics

The Plains CO₂ Reduction (PCOR) Partnership Atlas provides a profile of CO₂ sources and potential storage locations across the PCOR Partnership region. The revised sixth edition of the Atlas provides an up-to-date look at PCOR Partnership initiative activities, including additional regional characterization and updates on commercial projects. Additional background information on carbon capture, utilization, and storage (CCUS) is included to give a better understanding of how CCUS addresses concerns about climate change while allowing future energy needs to be met.

Soil Nitrate Prediction Using Ftir-Atr, Vis-Nir, And Raman Spectroscopy, Sabiha Ferdous

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Fourier transform infrared spectroscopy (FTIR) combined with Attenuated total reflectance (ATR), Visible-Near Infrared spectroscopy (Vis-NIR), and Raman spectroscopy (RS) are non-destructive techniques for rapid determination of nitrogen compounds in soil. Leveraging FTIR-ATR and Vis-NIR spectra using partial least squares regression (PLSR) modeling, the study aims to predict soil nitrate content and explored the feasibility of Raman spectroscopy to detect nitrate (NO₃^-), nitrite (NO₂^-), and ammonium (NH₄⁺) in soil. Soil samples were collected from four different fields, dried, sieved (2mm), and then used for collecting spectra (FTIR-ATR and Vis-NIR). Laboratory analysis was …

An Examination Of Thematic Research, Development, And Trends In Remote Sensing Applied To Conservation Agriculture, Zobaer Ahmed, Aaron Shew, Lawton Nalley, Michael Popp, V. Steven Green, Kristofor Brye

Center for Advanced Spatial Technologies Publications and Presentations

Conservation agriculture seeks to reduce environmental degradation through sustainable management of agricultural land. Since the 1990s, agricultural research has been conducted using remote sensing technologies; however, few previous reviews have been conducted focused on different conservation management practices. Most of the previous literature has focused on the application of remote sensing in agriculture without focusing exclusively on conservation practices, with some only providing a narrative review, others using biophysical remote sensing for quantitative estimates of the bio-geo-chemical-physical properties of soils and crops, and few others focused on single agricultural management practices. This paper used the preferred reporting items for systematic …

Exploitation Of Environmental Dna (Edna) For Ecotoxicological Research: A Critical Review On Edna Metabarcoding In Assessing Marine Pollution, Sakib Tahmid Rishan, Richard Kline, Md Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Highlights

• eDNA describes the genetic material of organisms present in aquatic environments.

• eDNA metabarcoding characterizes DNA of various marine species from a single sample.

• eDNA has enormous promise for ecotoxicological research in marine environments.

Abstract

The rise in worldwide population has led to a noticeable spike in the production, consumption, and transportation of energy and food, contributing to elevated environmental pollution. Marine pollution is a significant global environmental issue with ongoing challenges, including plastic waste, oil spills, chemical pollutants, and nutrient runoff, threatening marine ecosystems, biodiversity, and human health. Pollution detection and assessment are crucial to understanding the state of …

Wayne E. Sabbe Arkansas Soil Fertility Studies 2023, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil-test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.

Quality Assurance Project Plan - West Plains Pfas, Chad Pritchard

EWU PFAS Research Collection

Assessing the impacts of poly- and perfluoroalkyl substances (PFAS) contamination across multiple aquifers and multiple sources requires a detailed understanding of the hydrogeologic framework to quantifiably determine PFAS sources. The West Plains of eastern Washington is an ideal natural laboratory to study the fate and transport of PFAS because the general geohydrologic framework has been established and collaboration with several related PFAS projects will maximize the use of grant funds. This project will help the population, environment, and commercial entities of the West Plains by building a transport model, delineating PFAS contamination, and using unique PFAS distribution at different locations …

Predictive Understanding Of Lake Water Temperature And Dissolved Oxygen Profiles Across The Red River Basin Through Interpretable Machine Learning, Isabela Suaza Sierra

Open Access Theses & Dissertations

Accurately predicting lake water temperature (LWT) and dissolved oxygen (DO) is crucial for determining threshold values of fish survivability under warmer global conditions, with recreational fishing in reservoirs significantly contributing to regional economies, such as $779 million and $1,891 million annually to the economies of Oklahoma and Texas, respectively. Current mathematical models for temperature and oxygen profiles, which incorporate multi-layer and turbulent mixing equations, are complex and challenging to parameterize, particularly due to uncertainties in acquiring sufficient data for training and validation. Leveraging the flexibility and information extraction power of machine learning (ML) methods, this master thesis aimed to set …

Germplasm Enhancement Of Annual Forage Legumes Suitable For Use In Cold Highland Environments, H K. Firincioglu, N Karagullu, S Unal, A M. Abd-El Moneim

IGC Proceedings (1977-2023)

The Central Highlands (CH) of Turkey are characterized by cold winters and dry summers. Under these extreme air temperatures, forage crops are still underexploited as a part of crop rotations. Half of the total vetch hectarage in Turkey is in the CH, and farmers still use the local cultivars that have good adaptability but low yield potential. Therefore, with the aim of identifying and improving the annual forage legume species for the cold and dry environment of the CH, research work was carried out during the 1993/94 and 1994/ 95 crop seasons. Initial results showed that Hungarian vetch (Vicia …

Use Of The Grazing Animal In Forage Breeding, J H. Bouton, C S. Hoveland, R N. Gates

IGC Proceedings (1977-2023)

The objective of these studies was to determine, in the context of a forage breeding program, the effect of cattle grazing on survival of alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.), and tall fescue (Festuca arundinacea Schreb.). Different cultivars of each species were compared in grazed and ungrazed areas. Results consistently demonstrated that grazing reduced plant stands when compared to ungrazed conditions for each species tested. In alfalfa, however, cultivars developed for grazing tolerance showed much better grazing survival. Infection with the fungal endophyte, Acremonium coenophialum Morgan-Jones & Gams, likewise substantially increased grazing survival in …

Study Of Genotype X Environment Interaction In Alfalfa Forage Yield, S N. Acharya, G C. Kozub, H Najda, A Aasen

IGC Proceedings (1977-2023)

The response of alfalfa (Medicago sativa L.) forage yield to eight Alberta test sites was studied for the 1990 and 1991 production years. Cluster analysis was used to group locations and cultivars. Analyses of variances indicated genotype x environment (location) interaction for the first cut yield, the total yield and the difference between first and second cut yields. The Brooks, Bow Island (irrigation), Bow Island (dryland) and Provost locations always clustered together indicating that three of these four test sites may be eliminated without sacrificing reliability.