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A Large And Robust Legless Lizard (Squamata, Anguinae) From The Gray Fossil Site Of Eastern Tennessee, Justice D. Lamer Aug 2026

A Large And Robust Legless Lizard (Squamata, Anguinae) From The Gray Fossil Site Of Eastern Tennessee, Justice D. Lamer

Electronic Theses and Dissertations

The early Pliocene Gray Fossil Site in Tennessee preserved an abundance of microfossils, including numerous anguid lizard specimens. This includes the following elements: dentaries, a pterygoid fragment, a jugal, frontals, parietal fragments, dorsal and caudal vertebrae, and many osteoderms. Because these specimens had not been placed taxonomically beyond the subfamily level, comparative anatomy of similar elements from extant anguids and some quantitative data were used to provide more refined identifications. Using these methods, it was determined that a new, robust type of Ophisaurus is represented at the Gray Fossil Site. Important novel features include relatively robust dentaries, fewer but broader …


Evolution Of Propagator Wakes On The Kolbeinsey Ridge From An Integrated Geophysical Perspective, Ethan Stowell Aug 2026

Evolution Of Propagator Wakes On The Kolbeinsey Ridge From An Integrated Geophysical Perspective, Ethan Stowell

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

Oceanic lithosphere is formed following the extension and rifting of a continent, with new material generated at mid-ocean ridges. While ridges generally spread in the direction of extension, individual spreading centers are offset by perpendicular transform faults that break the ridges into individual segments. Ridge propagation, in which one ridge segment grows at the expense of another’s shortening, has been identified in global investigations as a poorly understood component of axial reorganization. This process leaves propagator wake structures composed of faults and pseudofaults visible as lows in Earth’s gravitational field, and transferred lithosphere with a distorted magnetic signature. This study …


Advancements In Modern Seismic Monitoring: Integrating Novel And Traditional Methods For Earthquake Detection, Characterization, And Structural Imaging, Marc Adrian Garcia Aug 2026

Advancements In Modern Seismic Monitoring: Integrating Novel And Traditional Methods For Earthquake Detection, Characterization, And Structural Imaging, Marc Adrian Garcia

Open Access Theses & Dissertations

Modern seismic monitoring has been transformed by machine-learning methods that detect and locate earthquakes at scales manual analysis cannot reach. This dissertation develops, validates, and applies such workflows across three settings that span the range of modern monitoring problems: a major subduction-zone aftershock sequence, the tectonic questions that sequence can answer, and an urban region without any local monitoring at all. First, I construct a high-resolution catalog for the aftershock sequence of the September 8, 2017, Mw 8.2 Tehuantepec, Mexico earthquake, by integrating deep-learning phase detection with established location and relocation methods. The resulting catalog of 11,374 relocated earthquakes is …


The Role Of Heterogeneity In Earthquake Rupture Dynamics: Insights From Friction Experiments On A 1-Meter Laboratory Fault, Alejandro Aguilar Aug 2026

The Role Of Heterogeneity In Earthquake Rupture Dynamics: Insights From Friction Experiments On A 1-Meter Laboratory Fault, Alejandro Aguilar

All Graduate Theses and Dissertations, Fall 2023 to Present

Tectonic faults are made of many kinds of rocks and minerals, creating natural weak and strong zones along faults where earthquakes occur. These differences can affect how faults move, including whether slip occurs slowly and quietly or suddenly and destructively during an earthquake. However, it is not fully understood how these variations influence when earthquakes start, how fast they spread, and whether they stop or grow into large ruptures. This research studies how different fault materials interact during earthquake slip. Using a large laboratory machine that simulates fault movement under realistic conditions, we recreate earthquake processes and closely measure how …


Greenhouse Gas Flux Response In Biochar- And Compost-Amended Lawn Soils Under Simulated Water Saturation Conditions, Angel Salinas, Chu-Lin Cheng, Engil Pereira, Rafael M. Almeida, James Jihoon Kang Aug 2026

Greenhouse Gas Flux Response In Biochar- And Compost-Amended Lawn Soils Under Simulated Water Saturation Conditions, Angel Salinas, Chu-Lin Cheng, Engil Pereira, Rafael M. Almeida, James Jihoon Kang

School of Earth, Environmental, & Marine Sciences Faculty Publications

Understanding greenhouse gas emission dynamics in lawn soils is important for improving climate change mitigation strategies in urban and suburban landscapes. In this greenhouse mesocosm study, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) fluxes were measured from 12 turfgrass soil columns arranged in an unreplicated, completely randomized 4 × 3 factorial design. Four amendment treatments (biochar, compost, bio-com [1:1 volume ratio of biochar and compost], and unamended control) were combined with three water-table conditions (full saturation, half saturation, and unsaturated), with a single column representing each treatment combination. Columns were irrigated at 1 cm day−1 for 24 days, …


Paleolimnology And Diatom Taxonomy From Lake Tanganyika, Sristika Adhikari Aug 2026

Paleolimnology And Diatom Taxonomy From Lake Tanganyika, Sristika Adhikari

All-Inclusive List of Electronic Theses and Dissertations

Lake Tanganyika is one of the world's largest freshwater ecosystems, supporting rich aquatic biodiversity and providing several ecosystem services to surrounding communities. Environmental changes such as rising lake surface temperatures, pollution, and land-use alterations threaten the lake’s sustainability. This research examines spatial and temporal variations in nutrient dynamics and primary productivity of Lake Tanganyika using diatom assemblages from multiple locations. Our findings indicate reduced nutrient levels and longer stratification periods in the lake’s central basin during most of the Common Era, as indicated by a remarkable increase in the relative abundance of long, needle-shaped planktonic Nitzschia species. In the southern …


Reconstruction Of Copepod Populations In Sierra Nevada Lakes Using The Diatom Fragilaria Cyclopum, Rorie Reisner Aug 2026

Reconstruction Of Copepod Populations In Sierra Nevada Lakes Using The Diatom Fragilaria Cyclopum, Rorie Reisner

All-Inclusive List of Electronic Theses and Dissertations

Copepods are one of the most abundant types of zooplankton, and their populations are often a vital part of the food chain, but their past populations cannot be estimated from lake sediments because their exoskeleton usually does not fossilize. Gull Lake is a glacial lake located in the subalpine region of the Sierra Nevada, California, which stands out due to the presence of the diatom Fragilaria cyclopum, which is rarer in diatom assemblages. Fragilaria cyclopum exclusively grows on copepods in lakes. Diatoms have an opaline silica skeleton that often fossilizes in lake sediments, so we can use this relationship with …


Reconstructing Stand-Age Structure In A Wet Miombo Woodland Using Dendrochronology, Zambia, Clara Tiyembekeze Zulu Aug 2026

Reconstructing Stand-Age Structure In A Wet Miombo Woodland Using Dendrochronology, Zambia, Clara Tiyembekeze Zulu

All-Inclusive List of Electronic Theses and Dissertations

Dendrochronological research in tropical Africa has remained limited, leaving critical gaps in stand-age structure and climate-growth relationships in seasonally dry tropical woodlands. This study reconstructed stand-age structure and assessed climate sensitivity in the wet Miombo woodland of African Explosives Limited (AEL) forest, Copperbelt Province, Zambia. Field sampling was conducted during four African Dendrochronology Fieldschools (2021-2024) using a Modified Variable Area Transect (MVAT) design across nine plots. The series intercorrelation was 0.351; the average mean sensitivity was 0.423. The oldest tree was 170 years old, and more than 70% of the sampled species showed potential for dendrochronology. Markhamia obtusifolia was the …


Forest Cover Effects On Canopy Interception Loss, Evapotranspiration, And Soil Infiltration On Stormwater Detention Basins, Alexandria N. C. Perez Aug 2026

Forest Cover Effects On Canopy Interception Loss, Evapotranspiration, And Soil Infiltration On Stormwater Detention Basins, Alexandria N. C. Perez

Electronic Theses and Dissertations

Developing cities and increased impervious surfaces has resulted in more surface runoff and severe flooding. Harris County, Texas has experienced major flooding events, such as Hurricane Harvey in 2017 which was estimated to be a 9,000-year flood event. The Harris County Flood Control District (HCFCD) is dedicated to creating, maintaining, and finding new ways to reduce flooding damage such as the use of detention basins as green infrastructure. These basins are either populated by grass or are planted with various tree species. This study will identify the planted trees’ canopy interception loss, reference evapotranspiration, and enhanced soil infiltration effects within …


Stratigraphic Analysis Of The Buda Limestone With Implications On Hydrocarbon Production Constraints, Madison And Houston County, Texas, Jeffrey C. Bridges Aug 2026

Stratigraphic Analysis Of The Buda Limestone With Implications On Hydrocarbon Production Constraints, Madison And Houston County, Texas, Jeffrey C. Bridges

Electronic Theses and Dissertations

The Fort Trinidad and Alabama Ferry fields located in eastern Madison and southern Houston County, Texas, have produced approximately 100 million barrels of oil equivalent to date, with approximately 65% of this being oil. However, there has been considerable variation in production within this Cretaceous carbonate play of the Fort Trinidad field, despite similar well completions and perforated intervals. The Buda Limestone, a key producing formation in the Cretaceous interval, is described as under-pressurized and often has lost circulation problems during drilling due to sub-pressure vertical fractures. Within the producing interval, the mechanisms for water production versus oil production are …


Technological Behaviour Of Pellets Containing Dried Green Crop, Christian Furll Jul 2026

Technological Behaviour Of Pellets Containing Dried Green Crop, Christian Furll

IGC Proceedings (1977-2023)

Pelleted dried green crop presents essential advantages compared to chaff and meal as processing forms. Normally, the solidity of the pellets does not exceed the values required by animal feeding. Abrasion resulting from turnover processes is at present too high, particularly for the discharge of bins. Belt conveyors, vibrating conveyors, and bucket elevators are suitable to convey pellets. Storage of pellets over long periods has to be done by respecting prescribed climate conditions. Zones with excessive portion of abraded par­ticles in the storing pile are a preferred cause for self-heating. Slit-type dosing units as well as dosing units equipped with …


Results Of Comparative Investigations Into The Chevving And Ruminating Activities Of The Dairy Cow Fed Dried Forage From Grass And Leguminous Crops, B Piatkowski, S Nagel Jul 2026

Results Of Comparative Investigations Into The Chevving And Ruminating Activities Of The Dairy Cow Fed Dried Forage From Grass And Leguminous Crops, B Piatkowski, S Nagel

IGC Proceedings (1977-2023)

The chewing and ruminating activities were studied of dairy cows fed grass, alfalfa, and straw of different physical forms. An electronic­ally controlled measuring device was applied. When feeding 8 kg of grass hay (32 % crude fibre in dry matter), the ruminating time was 5: 24 and 1 :49 hours (20,712 and 6,982 ruminat­ing movements) for chopped and ground + pelleted forages, respectively. It declined from 1 : 49 to 0: 0 l hours (from 6,929 to 70 move­ments) when hot-air dried alfalfa (23 % crude fibre) was fed in chopped and ground + pelleted forms, respectively. The ruminating time …


Feed Efficiency In Dairy Cows Of Roughages Preserved And Treated In Different Ways, M Zausch, E Boldt Jul 2026

Feed Efficiency In Dairy Cows Of Roughages Preserved And Treated In Different Ways, M Zausch, E Boldt

IGC Proceedings (1977-2023)

Trials were conducted with dairy cows to investigate the feed efficiency of grass-clover mixture (wilted silage, silage made of fresh material with addition of foDTiic acid, artifi­cially dried forage, pellets with varying portions of straw). The results obtained allow to draw the following conclusions:

As regards dry matter intake, digestibility, and feed efficiency, grass-dover for wilted silage should be wilted to give a OM content not exceeding 40 %.

Pelleting artificially dried grass-clover mix­ture and its use in mixed rations together with other separately pelleted components should be avoided.

The best feed efficiency is reached when dried grass-clover is converted …


The Influence Of Dried And Ensiled Grass On Rumen Fermen­Tation, J Voigt, B Piatkowski Jul 2026

The Influence Of Dried And Ensiled Grass On Rumen Fermen­Tation, J Voigt, B Piatkowski

IGC Proceedings (1977-2023)

Rumen-fistulated cows were used to study the influence of the forage preservation technique on rumen fermentation and holdup time of the feed in the rumen. Cocksfoot (Dactylis glomerata) preserved as wilted silage or dried green crop was fed in the following variants: wilted silage alone; wilted silage + sugar beet + protein supplement; dried green crop alone; dried green crop + sugar beet + protein supplement. As compared with dried green crop, the shares of true protein and sugar in wilted silage were reduced from 9.8 • to 6.4 '.'I􀉧 and from 7.7 to 1.8 %in DM, respectively. In comparison …


Changes In Feeding Value Of Preserved Grass And Legumes By The Action Of High Temperatures, R Prym, F Weissbach Jul 2026

Changes In Feeding Value Of Preserved Grass And Legumes By The Action Of High Temperatures, R Prym, F Weissbach

IGC Proceedings (1977-2023)

High temperatures acting on grass and legumes during preservation and storage, cause nutrient digestibility to deteriorate. Protein digestibility is likely to be most strongly affected. Digest­ibility measurements were performed on sheep to estimate the extent of heat damage suffered by dried green forage and silages. Various laboratory methods were applied for record­ing. such damage. The detennination of the acid-detergent insoluble crude protein portion proved a very suitable approach.


Growth And Nitrogen Retention Of Lambs Fed Alfalfa Dehy­Drated At Different Temperatures, H K. Goering Jul 2026

Growth And Nitrogen Retention Of Lambs Fed Alfalfa Dehy­Drated At Different Temperatures, H K. Goering

IGC Proceedings (1977-2023)

Alfalfa was dried at four temperatures ranging from 60 to 180 °C in two experiments to evaluate the effect on composition, diet di­gestibility, and growth by lambs. In Experi­ment I, the alfalfa was supplemented with 0.6 % salt and pelleted. In Experiment 2, alfalfa was supplemented with 24.4 % starch, 18.5% straw, 6% cane molasses, 0.5% sodium phosphate, and 0.6 % salt so that total nitrogen intake was not in excess of the protein require­ment for growth of the lambs. Cell wall, acid­detergent fiber, lignin, acid-detergent insoluble nitrogen, and pepsin insoluble nitrogen in­creased in the alfalfa dried at 180 °C. …


Non-Mechanical Field Losses In Wilting Grasses As Influenced By Different Factors, G Rucker, O Knabe Jul 2026

Non-Mechanical Field Losses In Wilting Grasses As Influenced By Different Factors, G Rucker, O Knabe

IGC Proceedings (1977-2023)

When wilting grasses, non-mechanical field losses of different extent may occur. The main factors influencing the extent of losses were: water content at cutting time, drying rate, temperature, amount of rain, swath den­sity, and content of water-soluble carbohy­drates in the crop.


The Effect Of Mechanical, Thermal And Chemical Treatment On The Loss Of Water From Cut Leaves Of Grasses, Colin Edward Harris Jul 2026

The Effect Of Mechanical, Thermal And Chemical Treatment On The Loss Of Water From Cut Leaves Of Grasses, Colin Edward Harris

IGC Proceedings (1977-2023)

Laboratory experiments have demonstrated that cut grass -leaves have a high resistance to water loss, probably largely due to the imper­meability of the surface cuticle to water vapour. This resistance can be reduced and drying rate increased by thermal and mechanical treatment, and by exposure to the vapour of boiling petroleum ether. The effectiveness of formic acid and tri-n-butyl phosphate suggests the possibility of using chemicals to increase the drying rate of grass crops cut for hay and dried in the field.


Measures For Increasing The Efficiency Of Hot-Air Drying Of Forage, Siegfried Prufer, Gerd Neubert Jul 2026

Measures For Increasing The Efficiency Of Hot-Air Drying Of Forage, Siegfried Prufer, Gerd Neubert

IGC Proceedings (1977-2023)

In the GDR, the drying of wilted green forage as well as of whole plants of cereals and grain maize considerably improves the effi­ciency of hot-air drying as a whole. The proc­essing of wilted crop and the inclusion of whole-plant drying in the drying pattern cause the throughput to increase by 30 to 50% and fuel consurnption per ton of dried crop to de­crease by up to 50 %, in comparison with drying of fresh green forage containing 15 to 18 % dry matter. Hot-air drying is particularly suitable for feed production along industrial lines. -Being but little dependent on …


Gdr Standard Plant For Producing Feed Pellets On Straw Basis, Gerheard Schmidt Jul 2026

Gdr Standard Plant For Producing Feed Pellets On Straw Basis, Gerheard Schmidt

IGC Proceedings (1977-2023)

Following the international trend, livestock production units are growing in size. Straw, a major feed reserve, must be effectively utilized to meet the growing roughage requirements, especially of ruminants. Therefore, in the GDR a standard feed pelleting plant (type GF A) was developed and put to commercial production. The various machines and equipment em­ployed in the different stages of the GFA pellet­ing technology are explained in detail. The use of that standard feed pelleting plant shows the advantages of processing straw for semi-finished and finished feeds.


The Efficiency Of Producing And Feeding Complete-Ration Feed Briquets Containing Forage Chop, G V. Blagoveshcheski, V M. Sokolov Jul 2026

The Efficiency Of Producing And Feeding Complete-Ration Feed Briquets Containing Forage Chop, G V. Blagoveshcheski, V M. Sokolov

IGC Proceedings (1977-2023)

Production of forage chop from a clover­timothy mixture is efficient when harvesting the forage between the shooting of clover (35 to 40 cm stand height) and mid-flowering. For high-temperature drying, each vegetative stage of the plants requires a clearly defined regime. When establishing formulas for com­plete-ration feed briquets containing clover­timoihy chop harvested before clover budding, the protein/carbohydrate ratio must be bal­anced by supplementing the ration with 30 p.c. barley meal and 29 p.c. straw; when the mix­ture was harvested during budding, phos­phorus supplementation (one p.c. monocal­cium phosphate) is necessary, whilst the mix­ture harvested during flowering has to be supplemented with …


The Production Of Dry Feeds From Straw And Green Forage In The Gdr, Fritz Berg Jul 2026

The Production Of Dry Feeds From Straw And Green Forage In The Gdr, Fritz Berg

IGC Proceedings (1977-2023)

In the GDR, at present about 9% of the feed energy requirement of cattle is covered by dry feeds, above all mechanically processed and chemically treated straw as well as dried green forages. This share is expected to rise to 15 % in forthcoming years. On the basis of technological fundamentals devised by animal nutritionists, corresponding production processes are being developed and perfected. They allow to convert the feedstuffs into a physical and chemical form favourable to high intake; in addition, the feeding value of high-fibre feedstuffs is improved. In this way, the feedstuffs are fed in favourable com­bination as …


Evaluation And Determination Off Actors Defining The Length Of Thin-Stalked Green Forage Chop, Peter Szendro Jul 2026

Evaluation And Determination Off Actors Defining The Length Of Thin-Stalked Green Forage Chop, Peter Szendro

IGC Proceedings (1977-2023)

A more exact analysis of the length distribution of chopped material from thin-stalked green forage crops provides more information for the further processing of this material and for comparing the quality of work of the different technologies. Material cut into longer and less homoge­neous chop with heavier destruction of the green plant particles shows properties more suitable for further processing than chop harvested with a self-propelled precision-chop forage harvester. In consideration of the special importance of the questions discussed it seems advisable to continue the experiments and to perform them under production conditions as well; the results thus obtained will …


Organization Of Wilted Silage Production Along Industrial Lines In The Selbelang Inter-Farm Cooperative Crop Produc­Tion Division, Hunter Watzke, Karl Bachmann Jul 2026

Organization Of Wilted Silage Production Along Industrial Lines In The Selbelang Inter-Farm Cooperative Crop Produc­Tion Division, Hunter Watzke, Karl Bachmann

IGC Proceedings (1977-2023)

The production of high-quality wilted silages on the basis of highly efficient machines and facilities for harvesting and preservation in the Selbelang inter-farm cooperative crop pro­duction division (KAP) is determined by the use of industrial methods of production. Ob­servance of optimum spans for harvesting forage to be used for the production of wilted silage, and the full utilization of machinery and facilities at rising levels of labour pro­ductivity and declining cost are achieved by way of complex and shift employment of machines, facilities, and workers. The size of machine complexes and their performance are dependent on the shape, equipment and …


Possibilities Of Ensiling Meadow Grass With Different Water Content, Roman Moraczewski, Helena Jurkiewicz Jul 2026

Possibilities Of Ensiling Meadow Grass With Different Water Content, Roman Moraczewski, Helena Jurkiewicz

IGC Proceedings (1977-2023)

The paper involves results of investigations into the influence of various methods of grass preservation, different cutting times, and dif­Jerent water contents on the nutrient and min­eral levels in the silage. These results show good possibilities of preserving meadow grass by ensiling. Silage fodder has higher contents of crude protein, crude fibre, crude fat, and ash constituents than are found in hay dried under optimum conditions.


Material And Processing Characteristics Of Grasses And Grass Silages, Manfred Muller, Georg Otto Jul 2026

Material And Processing Characteristics Of Grasses And Grass Silages, Manfred Muller, Georg Otto

IGC Proceedings (1977-2023)

Material and processing characteristics are essential initial values for planning of proce­dures in industrialized crop production. From the technological stages and process sequences from grass mowing to removing the silage, the following key operations can be derived: chop­ping,. compressing, storing, and removing. For adequate planning of procedures it is necessary to determine the quantitative relations between the essential factors: chopper throughput, pro­portion of short chop, crude fibre content, and relative final density. A relation suitable for practical application and providing sufficient accuracy is established for estimating the mean dry matter content of a trailer load. If high­quality silage is to …


Comparison Of Three Techniques Of Forage Conservation, Tereza Kotapska, Tadeusz Olszewski Jul 2026

Comparison Of Three Techniques Of Forage Conservation, Tereza Kotapska, Tadeusz Olszewski

IGC Proceedings (1977-2023)

At the Instytut Mechanizacji i Elektryfikacji Rolnictwa technological trials have been per­formed on green forage conservation under plastic sheeting using round formers from the Italian manufacturers Frigieri, a silage press from the French firm Kuhn, and portable seg­ments of Polish production for the erection clamp silos. The trials covered the operating quality of the equipment and the evaluation of silage quality. During the trials, the performance of the equipment on erecting the silos and specific labour expenditure were established. In addi­tion, an economic rating was made of the ensiling process and of the general suitability of the above methods for …


Losses And Stability Of Silage In Dependence On The Degree Of Air Influence, G Weise, H Rettig, G Suckow Jul 2026

Losses And Stability Of Silage In Dependence On The Degree Of Air Influence, G Weise, H Rettig, G Suckow

IGC Proceedings (1977-2023)

On the basis of model concepts of physical gas exchange, a method has been developed for studying the complex relations existing be­tween the parameters indicating ensilability and the specific local conditions for silage making (degree of anaerobiosis). Conclusions are drawn as to quantitative relations between the depth of the peripheral layers of a silage stock that are endangered by air, the initial density of the silage material, and the sealing of the silage top during the filling and storage periods. Therefrom, certain thresh­olds can be derived for minimum filling height per day as depending on the initial density of the …


Factors Influencing The Formation Of Effluent In Forage Ensiling, G Peters, F Weissbach Jul 2026

Factors Influencing The Formation Of Effluent In Forage Ensiling, G Peters, F Weissbach

IGC Proceedings (1977-2023)

The amount of effluent formed in ensiling forage crops depends, above all, on the dry matter content of the initial material, on the pressure exerted on the feed stock, and on the kind of crop ensiled. Expected values of effluent a­mount were derived from model experiments and calculations. Adequate wilting of suitable forage crops will allow to reduce or prevent effluent formation. The degree of wilting re­quired depends on the height of the feed stock and on the kind of silo used. The limit of 30 % DM in initial material, so far generally accepted for effluent formation, only applies …


Wilted Silage Production For The Supply Of Large Cattle Populations, Wilhelm Schwandt Jul 2026

Wilted Silage Production For The Supply Of Large Cattle Populations, Wilhelm Schwandt

IGC Proceedings (1977-2023)

For supplying large cattle populations with high-quality roughage it is necessary to make available big forage batches of good and large­ly uniform quality. From 4,675 hectares of seed­ed grassland, the ZBE Pflanzenproduktion Ferdinandshof(Ferdinandshofinter-farmestab­lishment for crop production) every year pro­duce in good quality more than 80,000 tons of wilted silage. The material and technical basis of this forage production along industrial lines consists of powerful machine systems that are operated in multi-machine complexes, the oper­ators doing shift work.