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Possibilities Of Dry Matter Production From Forage Plants Under Different Climatic Conditions, Th Alberda Jul 2026

Possibilities Of Dry Matter Production From Forage Plants Under Different Climatic Conditions, Th Alberda

IGC Proceedings (1977-2023)

On the basis of the gross photosynthesis of closed green grass swards the net potential dry herbage production of permanent pastures is calculated for the climatic and soil conditions for the so-called broad soil regions and summa­rized per continent. The values thus obtained form the upper level of dry herbage production to be reached on the prevailing permanent pas­ture area. Subsequently the minimum level of dry herb­age production is calculated, based on data on the production of marketed secondary prod­ucts as meat and milk. Since not all these secondary products are marketed and since not all the herbage produced is …


The Gene Pool And Its Use In Breeding Grassland Plants, Anna Novoselova Jul 2026

The Gene Pool And Its Use In Breeding Grassland Plants, Anna Novoselova

IGC Proceedings (1977-2023)

1. The gene pool of grassland plants is of great diversity and localized in certain centres of origin where the carriers of germ plasma are concentrated for the most important bio­logical characters and properties of a great variability of species.

2. New intensive varieties for mowing and grazing have been bred by advanced breeding methods and by taking advantage of the gene pool of the most important plant species throughout the world.

3. Wild-growing species were found to have great prospects for opening up soils of poor productivity by mowing and grazing use. They constitute a great reserve of genetic …


The Environment And Population Differences In Anjan Grass (Cenchrus Ciliaris) In Western India, S C. Pandeya Jul 2026

The Environment And Population Differences In Anjan Grass (Cenchrus Ciliaris) In Western India, S C. Pandeya

IGC Proceedings (1977-2023)

Cenchrus ciliaris (anjan or buffel grass) is a gregarious fodder species with high nutritive value. The species is an inhabitant of drier sandy areas throughout Africa, Canary Island, Madagascar and eastwards to India, where it mostly occurs in western parts of the country, constituting the States of Gujarat, Rajasthan, Hayana and the adjoining portions of Punjab, U ttar Pradesh and Madhya Pradesh ( called here in as Western India). In Western India, Cen­chrus ciliaris (Cc) variously dominates the nat­urally occurring grazing lands exhibiting great morphological variations with respect to habit. and spike characters. The ecoclimate of Western India is arid …


Review Of 50 Years Grassland Farming And Trends Of Development In The Further Intensification Of Forage Production In The German Democratic Republic, Eberhard Wojahn Jul 2026

Review Of 50 Years Grassland Farming And Trends Of Development In The Further Intensification Of Forage Production In The German Democratic Republic, Eberhard Wojahn

IGC Proceedings (1977-2023)

This our XIII International Grassland Congress is being held at the invitation of the Govern­ment of the German Democratic Republic following the decision of the XII International Grassland Congress in Moscow in 1974 that this Congress shall be held as a jubilee event here in Leipzig. It is the Jubilee Congress reminding us of the First International Grass­land Congress which was held 50 years ago, during the last days of May, 1927, in this time-honoured University town and centre of world trade. Because of that jubilee character this XIII International Grassland Congress is of very special importance.


Influence Of Feeding On Health And Productivity Of Ruminants, Alexander Sommer Jul 2026

Influence Of Feeding On Health And Productivity Of Ruminants, Alexander Sommer

IGC Proceedings (1977-2023)

As to the utilization of plant matter not suited for direct consumption by man, ruminants are of outstanding importance. This fact is related with the function of their specific stom­ach system. The paper discusses the microbial protein synthesis from NPN compounds. When 50 per cent of digestible crude protein required by fattening cattle were replaced, daily live weight gains of 997 g were reached; beef quality was not affected. Similarly favourable results were obtained with dairy cows when replacing by NPN compounds 50 to 100 per cent of extracted meals. Further on, the problem of crude-fibre diges­tion in connection with …


Elemental Analysis Of Upper Devonian To Lower Mississippian Organic-Rich Mudstone Cores From Kentucky By Portable X-Ray Fluorescence (Pxrf), Alex M. Washburn Jul 2026

Elemental Analysis Of Upper Devonian To Lower Mississippian Organic-Rich Mudstone Cores From Kentucky By Portable X-Ray Fluorescence (Pxrf), Alex M. Washburn

KGS Research Data Set

This dataset contains high-density portable X-ray fluorescence (pXRF) elemental analyses of 1,867 m (6,125 ft) of Upper Devonian to Lower Mississippian organic-rich mudstone cores from Kentucky. Analyses were collected from cores across the Illinois Basin, Cincinnati Arch, and Appalachian Basin to support regional evaluation of elemental variability, chemostratigraphy, and redox-sensitive trace-metal enrichment in Devonian–Mississippian mudstone successions. All measurements were conducted using a Bruker Tracer 5 pXRF analyzer with the factory “Mudrock Air” calibration, using analytical settings optimized for both low-atomic-number elements and transition metals/redox-sensitive trace elements. Reference materials SARM-41 and SGR-1 were analyzed throughout the analytical sequence to monitor instrument …


Synoptic Conditions Favoring Tropical Cyclone-Enhanced Southwest Monsoon High Precipitation Events In The Philippines, Alwin Andriel L. Bathan, Lyndon Mark P. Olaguera, Faye Abigail T. Cruz, Jose Ramon T. Villarin, John A. Manalo, Jun Matsumoto Jul 2026

Synoptic Conditions Favoring Tropical Cyclone-Enhanced Southwest Monsoon High Precipitation Events In The Philippines, Alwin Andriel L. Bathan, Lyndon Mark P. Olaguera, Faye Abigail T. Cruz, Jose Ramon T. Villarin, John A. Manalo, Jun Matsumoto

SOSE Affiliate: Manila Observatory

The interaction of tropical cyclones (TCs) with the southwest monsoon frequently causes heavy precipitation events (HPEs) and widespread flooding across the Philippines. Despite their substantial socio-economic impacts, the synoptic conditions that favor these events remain insufficiently understood, underscoring the need for systematic investigation to help improve forecasting and risk assessment. Lag composite analysis of daily rainfall records and reanalysis data from July to September for the period 1981–2023 shows that HPEs are more likely to occur when: (1) enhanced monsoon westerlies are present over the tropical Indian Ocean for at least nine days before the HPE, (2) a TC passes …


Glacier Elevation Difference Data For The Conterminous U.S., Andrew G. Fountain, Bryce Allen Glenn, Christopher Mcneil, Brian Menounos Jul 2026

Glacier Elevation Difference Data For The Conterminous U.S., Andrew G. Fountain, Bryce Allen Glenn, Christopher Mcneil, Brian Menounos

Geology Faculty Datasets

Historic and recent elevation data for the glaciers in the conterminous US were differenced to estimate glacier mass and volume change.

Historic glacier elevations were obtained from the USGS National Elevation Dataset (https://doi.org/10.15760/geology-data.04), a digitized product from the USGS 1:24,000 paper topographic maps that included the glacier extent (Gesch, 2007). Recent glacier elevations were derived from aerial lidar and from satellite radar. The lidar data were largely obtained from the USGS 3D Elevation Program (Stoker and Miller, 2022; US Geological Survey, 2024), and filtered by acquisition date using only those data collected between mid-summer and early autumn. The …


Crustal Structure Of The Vøring Plateau And Vøring Spur From Joint Refraction And Reflection Travel-Time Tomography, Anika Nawar Mayeesha Jul 2026

Crustal Structure Of The Vøring Plateau And Vøring Spur From Joint Refraction And Reflection Travel-Time Tomography, Anika Nawar Mayeesha

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Crustal architecture of the Vøring Plateau and Vøring Spur in the mid-Norwegian continental margin remains debated because the geophysical data in the area do not uniquely constrain whether the crust is continental, oceanic, or transitional. This study reanalyzes wide-angle ocean-bottom seismometer data from Profile 11-03 across the Vøring passive continental margin using joint travel-time tomography of crustal refractions and Moho reflections. A total of 6,760 first-arrival picks and 542 PmP picks from sixteen instruments were inverted for P-wave velocity and reflector depth. Three starting models were inverted independently to test sensitivity to the initial crustal configuration. The first two used …


Observing System Simulation Experiments To Investigate Impacts Of Deep-Tropospheric Uas Flights On Forecasts, Kenneth Alexander Swan Jul 2026

Observing System Simulation Experiments To Investigate Impacts Of Deep-Tropospheric Uas Flights On Forecasts, Kenneth Alexander Swan

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Uncrewed aircraft systems have emerged as a promising option to address meteorological gaps in observations in the lower troposphere. With recent advancements, UAS may be able to address gaps aloft in areas that lack coverage from radiosondes and commercial aircraft. UAS have shown the potential to significantly benefit NWP forecasts from profiles in the lowest 2 km AGL, but the impact of UAS profiles to the tropopause has yet to be quantified. Additionally, the impacts of hazardous flying conditions that UAS would encounter need to be addressed to guide future UAS capabilities. To address these questions, we designed an observing …


An Emergent Seafood Nationalism Takes Hold In The United States, Owen Temby Jul 2026

An Emergent Seafood Nationalism Takes Hold In The United States, Owen Temby

School of Earth, Environmental, & Marine Sciences Faculty Publications

This paper introduces the concept of ‘seafood nationalism’ to describe how, since 2024–2025, the United States increasingly uses tariffs, trade remedies, food safety enforcement and origin-based rules to favour American seafood over foreign products. Federal actions include Executive Order 14276, Restoring American Seafood Competitiveness, which directs agencies to address unfair trade practices, unsafe imports and to develop a coordinated seafood trade strategy. Additional measures include a tariff package imposing a 10% duty on nearly all seafood imports and 30% on seafood from China, as well as new anti-dumping and countervailing duty orders on warm-water shrimp. This paper presents Gulf …


Farm Workers And The Structural Basis Of Climate Change Perceptions, Cody Mortell, Anna Erwin, Zhao Ma, Dongkyu Kim, Elizabeth Rodriquez, Marla Perez-Lugo Jul 2026

Farm Workers And The Structural Basis Of Climate Change Perceptions, Cody Mortell, Anna Erwin, Zhao Ma, Dongkyu Kim, Elizabeth Rodriquez, Marla Perez-Lugo

School of Earth, Environmental, & Marine Sciences Faculty Publications

Farm workers are particularly vulnerable to climate change, especially from extreme heat; however, little is known about how they perceive this risk. This study examines climate change perceptions (CCP) among 404 farm workers surveyed in person in the Lower Rio Grande Valley, Texas from April to May 2024. Guided by Pierre Bourdieu’s theory of practice, we conducted a latent class analysis of economic, cultural, social, and symbolic capital indicators to identify distinct class profiles. We then assessed CCP by latent profile, using two primary outcome variables: (1) perceived temperature trends in the region (assessed alongside NOAA data) and (2) perceived …


Book Review: Atlas Of Minerals And Igneous And Metamorphic Rocks In Thin-Section (2025) By Alessandro Da Mommio And Victoria Pease., Kenneth L. Brown Jul 2026

Book Review: Atlas Of Minerals And Igneous And Metamorphic Rocks In Thin-Section (2025) By Alessandro Da Mommio And Victoria Pease., Kenneth L. Brown

Geology and Environmental Geoscience Faculty Publications

"Optical mineralogy and petrography not only equip us with the skills necessary to address society’s growing need for rock and mineral resources but also awaken a deeper curiosity—inviting us into moments of discovery that change the way we understand these resources. From observing the vibrant and mesmerizing interference colors of a dunite thin section to examining the uniaxial interference figure of calcite, many of us can still recall the first time we peered through the oculars of a polarizing microscope. Atlas of Minerals and Igneous and Metamorphic Rocks in Thin-Section is an exceptional reference textbook, which nurtures that curiosity and …


Hydrogeochemical Characterization Of Groundwater In Fractured Crystalline Basement Aquifers In Dodoma, Central Tanzania: Implications On Water Quality For Domestic And Irrigation Applications, George J. Ishabairu, Simon R. Melchioly, Charles H. Kasanzu, Gabriel D. Mulibo Jun 2026

Hydrogeochemical Characterization Of Groundwater In Fractured Crystalline Basement Aquifers In Dodoma, Central Tanzania: Implications On Water Quality For Domestic And Irrigation Applications, George J. Ishabairu, Simon R. Melchioly, Charles H. Kasanzu, Gabriel D. Mulibo

Tanzania Journal of Science

Assessment of groundwater hydrogeochemistry characteristics of aquifers plays a vital role in establishing water quality status and its suitability for human and industrial use. The main objective of this research was to carry out hydrogeochemical characterization of groundwater and assess its impacts on water quality and spatial variability of groundwater geochemistry in Dodoma, Tanzania. The methods used include groundwater sampling, laboratory analysis to determine physico- chemical parameters and data processing to classify the groundwater hydrochemical facies. The results show that the average value for pH is 7.2, for electrical conductivity (EC) is 1108 µS/cm and for total dissolved solids (TDS) …


Hydroclimatic Whiplash Across The Contiguous United States: Characterizing Wet–Dry Transitions In Pdsi And Phdi, James Lam, Thomas Christopher Piechota Jun 2026

Hydroclimatic Whiplash Across The Contiguous United States: Characterizing Wet–Dry Transitions In Pdsi And Phdi, James Lam, Thomas Christopher Piechota

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Hydroclimatic whiplash, characterized by rapid transitions between wet and dry conditions, poses a growing challenge for water resource management and ecosystem stability. However, the spatial and statistical characteristics of wet–dry transitions across the contiguous United States are not fully understood. This study analyzed Palmer Drought Severity Index (PDSI) and Palmer Hydrological Drought Index (PHDI) records from 344 NOAA climate divisions spanning 1895–2024. Whiplash was defined as a transition between severe drought and severe wetness within 12-month rolling windows. Statistical descriptors including lag-1 autocorrelation, variance, and skewness were evaluated for whiplash and non-whiplash windows to assess differences between them. Whiplash hotspots …


An Overlooked Terrestrial Archive: Freshwater Cements And Hydroclimate Signals In Quaternary Glaciogenic Deposits, Owen F. Mccaffrey, Ian Z. Winkelstern, Tara A. Kneeshaw, Melinda C. Higley Jun 2026

An Overlooked Terrestrial Archive: Freshwater Cements And Hydroclimate Signals In Quaternary Glaciogenic Deposits, Owen F. Mccaffrey, Ian Z. Winkelstern, Tara A. Kneeshaw, Melinda C. Higley

University Faculty Publications and Creative Works

Quaternary glaciogenic deposits, which serve as vital groundwater aquifers, are often partially cemented with carbonate minerals, but the timing of emplacement of these cements and their geochemical conditions of formation remain understudied. Here, we integrated petrography, δ18O, Mg/Ca, and clumped isotope (Δ47) data from two calcitecemented outcrops in western Michigan (USA) to investigate the origin of glacial sediment cements. The two sites have contrasting topographic and textural settings reflecting distinct formation conditions. The elevated Wabasis Lake deposit records sequential phreatic-to-vadose cementation, while the Cherry Valley Sands site, very close to the modern water table, shows a …


R Code And Supporting Data For "Fast And Slow Water Handling Strategies Explain Pinyon Pine Decline And Juniper Expansion", Andrew Kulmatiski, Muhammad Faraz Rehman Jun 2026

R Code And Supporting Data For "Fast And Slow Water Handling Strategies Explain Pinyon Pine Decline And Juniper Expansion", Andrew Kulmatiski, Muhammad Faraz Rehman

Browse all Datasets

This repository contains the datasets, R scripts, HYDRUS-1D model files, weather data, and supporting materials used for the M.S. thesis, "Fast and Slow Water Handling Strategies Explain Pinyon Pine Decline and Juniper Expansion." The study investigated root water uptake and water-use strategies of pinyon pine (Pinus edulis) and Utah juniper (Juniperus osteosperma) using stable isotope tracer experiments, soil water flow modeling, leaf water potential measurements, stomatal conductance measurements, and environmental data collected across an aridity gradient in southern Utah, USA.


Instructions To Authors, Academy Editors Jun 2026

Instructions To Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Journal Acknowledgements And Editorial Board, Academy Editors Jun 2026

Journal Acknowledgements And Editorial Board, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Keynote Address And Meeting Program, Academy Editors Jun 2026

Keynote Address And Meeting Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Business Meeting Report (Secretary's And Treasurer's Report), Academy Editors Jun 2026

Business Meeting Report (Secretary's And Treasurer's Report), Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Sperm Morphology In The Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth Jun 2026

Sperm Morphology In The Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth

Journal of the Arkansas Academy of Science

Studies by Scheltinga et al. (2002) and Scheltinga and Jamieson (2003) provide the most comprehensive analysis and only review of sperm morphology in Narrow-Mouthed Frogs (family Microhylidae). Of the 490+ species known to occur in this anuran family (Vitt and Caldwell 2014), only 3 are distributed in the United States (Powell et al. 2016), and 2 of these occur in Arkansas (Trauth et al. 2004). Surprisingly, sperm studies on only 12 microhylid species have been conducted (Scheltinga and Jamieson 2003), and no sperm studies are available on any North American species.


Multiple Nuclear Configurations And Microtubular Arrangements In Spermatozoa Of The Western Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth Jun 2026

Multiple Nuclear Configurations And Microtubular Arrangements In Spermatozoa Of The Western Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth

Journal of the Arkansas Academy of Science

I examined the ultrastructure of spermatozoa of the Western Siren, Siren nettingi, using transmission electron microscopy. My primary objective in this study was to elucidate, for the first time, the unique morphological complexity of biflagellated sperm in this species. This study also represents my fifth addition in a series of investigations that highlight the novel nature of all aspects of spermatogenesis in this salamander I show the basic sperm transverse and sagittal design which includes a nucleus, 2 axial fibers supporting 2 undulating membranes which have 2 axonemes residing at their terminal ends, several circular mitochondria, and several electron-dense masses. …


Binucleation And Seasonal Cycle Of Sertoli Cells In The Western Lesser Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth Jun 2026

Binucleation And Seasonal Cycle Of Sertoli Cells In The Western Lesser Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth

Journal of the Arkansas Academy of Science

I examined binucleation and the seasonal cycle of Sertoli cells in the Western Siren (Siren nettingi) using light microscopy and transmission electron microscopy. My primary objective in this study was to report, for the first time, the presence of double nuclei in Sertoli cells in a salamander. This study also represents the sixth contribution in a series of investigations that highlight the novel nature of all aspects of spermatogenesis in this unique salamander. My findings add to a growing list of extraordinary morphological and reproductive features that distinguish this salamander from all other vertebrates.


Distal Urogenital Anatomy And Epithelial Morphology In The Male Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth Jun 2026

Distal Urogenital Anatomy And Epithelial Morphology In The Male Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth

Journal of the Arkansas Academy of Science

I investigated the microanatomy of the distal urogenital system in male Eastern Narrow-Mouthed Frogs (Gastrophryne carolinensis) from a small sample (n = 5) collected in central Arkansas in April, May, and July (2021) and May 2022. Specifically, my primary goals were to elucidate the histology of the following: (1) the paired Wolffian (urogenital) ducts caudally from the kidneys to their merging with the urodeum of the cloaca, (2) the structure of seminal vesicles, and (3) the epithelial morphologies among the distal urogenital tract, the posterior alimentary canal, and the cloaca. My histological analysis confirmed the presence of …


Academy Presidents And Institutional Members, Academy Editors Jun 2026

Academy Presidents And Institutional Members, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Table Of Contents, Academy Editors Jun 2026

Table Of Contents, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Journal Of The Arkansas Academy Of Science Volume 79, Academy Editors Jun 2026

Journal Of The Arkansas Academy Of Science Volume 79, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Advances In Regional Fracturing Technology Using Underground Long Directional Boreholes For The Prevention And Control Of Coal-Rock Dynamic Disasters And Its Engineering Practices, Zheng Kaige, Zhang Jian, Sun Siqing, Chen Dongdong, Zhang Qun, Li Bingang, Guo Wei, Liu Le, Jia Bingyi, Wang Zeyang, Dai Nan, Wang Haojie Jun 2026

Advances In Regional Fracturing Technology Using Underground Long Directional Boreholes For The Prevention And Control Of Coal-Rock Dynamic Disasters And Its Engineering Practices, Zheng Kaige, Zhang Jian, Sun Siqing, Chen Dongdong, Zhang Qun, Li Bingang, Guo Wei, Liu Le, Jia Bingyi, Wang Zeyang, Dai Nan, Wang Haojie

Coal Geology & Exploration

Objective Coal-rock dynamic disasters represent a key challenge to the safe and efficient mining of deep coals, rendering it urgent to develop regional, advance, and precise technologies for proactive disaster prevention and control. Advances The regional fracturing technology using underground long directional boreholes for disaster prevention and control in coal mines originated from ground fracturing. To date, a regional fracturing theory oriented to geological origin, mining responses, and disaster-causing mechanisms has been developed. Furthermore, a core equipment system incorporating high-power directional drilling rigs, variable frequency fracturing pump sets with high injection rates of fracturing fluids, infinite stage fracturing, and tools …


Summary And Reflections On Coal And Coalbed Methane Co-Production And Coalbed Methane Extraction In Coal Mining Areas, Zhang Sui’An, Zhang Xiao, Li Xuechen, Hu Huiting Jun 2026

Summary And Reflections On Coal And Coalbed Methane Co-Production And Coalbed Methane Extraction In Coal Mining Areas, Zhang Sui’An, Zhang Xiao, Li Xuechen, Hu Huiting

Coal Geology & Exploration

Background To curb coal mine gas accidents from sources, exploit low-carbon and clean coalbed methane (CBM) resources, and protect the atmospheric environment (achieved by methane emission reduction in coal mining areas), the authors’ team, by working with Shanxi Jincheng Anthracite Mining Group and cooperating closely with relevant research institutes, colleges, and universities, has progressively developed theories with clear concepts and scientific connotations, as well as relevant technical systems and industrial paradigms, for coal and CBM co-production through over two decades of original, integrated, and cross-industry innovations (spanning across fluid and solid mineral industries), along with theoretical exploration, technological research and …