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2024

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Articles 1201 - 1230 of 3173

Full-Text Articles in Earth Sciences

The Effect Of Slurry And Dirty Water Application To Swards On Grazing Behaviour In Dairy Cows, S Danby, J A. Laws, P D. Penning, B F. Pain, E Owen Jul 2024

The Effect Of Slurry And Dirty Water Application To Swards On Grazing Behaviour In Dairy Cows, S Danby, J A. Laws, P D. Penning, B F. Pain, E Owen

IGC Proceedings (1977-2023)

In preference tests using pairs of turves in boxes (treated and control), dairy cows were more averse to surface spread than shallow injected slurry and more averse to slurry than dirty water. Effects of slurry persisted for up to 6 weeks, with fewer bites and less herbage removed from treated swards compared to control swards. Aversion to slurry may be decreased by injection. Effects of dirty water persisted for only 14 days.

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Applications Of Height-Based Grazing Management In Mixed Swards, A Singh, J E. Johnston, E A. Clark Jul 2024

Applications Of Height-Based Grazing Management In Mixed Swards, A Singh, J E. Johnston, E A. Clark

IGC Proceedings (1977-2023)

Grazing efficiency and livestock performance were compared on swards rotationally grazed down to either 50 or 100 mm for three years. With a fixed entry height of 200-250 mm, standing swards of mixed grasses and white clover (Trifolium repens L.) were stratified into 50 mm vertical layers both pre- and post-grazing. Through four or five cycles of grazing each year for three years, a fixed entry height range stabilized total standing herbage at 3250 to 3690 kg OM ha-1. Organic matter on-offer above 100 mm was 36, 45, and 43% of total standing herbage in the three years, compared …

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Ingestive Behavior Of Fistulated And Intact Sheep Grazing Grass And Legumes Indoors And Outdoors, Y M. Gong, J Hodgson, M G. Lambert Jul 2024

Ingestive Behavior Of Fistulated And Intact Sheep Grazing Grass And Legumes Indoors And Outdoors, Y M. Gong, J Hodgson, M G. Lambert

IGC Proceedings (1977-2023)

Components of short-term ingestive behaviour were recorded for fistulated and intact sheep grazing turves in indoor crates, and for esophageal-fistulated sheep grazing swards in situ in outdoor cages. Perennial ryegrass, orchard grass and white clover at vegetative and reproductive growth stages were offered to the sheep. Bite weight, depth, area and volume did not differ between sheep grazing indoors and outdoors, nor between intact and fistulated sheep. Bite rate of fistulated sheep was slower indoors than outdoors (25.3 versus 32.1 bites/min), and intact sheep had a higher biting rate (36.7 versus 25.3 bites/min) than fistulated sheep. Bite weight was over-estimated …

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Dairy Production From Pasture In Southern China, P.N P. Matthews, J Hodgson, A.C P. Chu, W L. Jiang, C B. Luo Jul 2024

Dairy Production From Pasture In Southern China, P.N P. Matthews, J Hodgson, A.C P. Chu, W L. Jiang, C B. Luo

IGC Proceedings (1977-2023)

This paper covers the development of dairy production systems as part of the UNDP funded Agro-grasslands Systems Development Project in Guizhou Province, China. The basic philosophy for the project was for local adaptation of New Zealand technology for developing dairy production systems based on pastures. The dairy production systems were established and the outputs of the project successfully achieved. Net incomes of smallholder farmers increased from a baseline of RMB $140 to RMB $1740 per annum over a three year period. Based on the experienced gained in setting up these systems local researchers, administrators, extension personnel and smallholders were able …

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Trace Mineral Status Of Beef Cattle Grazing Semiarid Rangelands Of North Mexico, J R. Kawas, G T. Armienta, E Olivares, O Torress, J J. Kawas, F Garza Jul 2024

Trace Mineral Status Of Beef Cattle Grazing Semiarid Rangelands Of North Mexico, J R. Kawas, G T. Armienta, E Olivares, O Torress, J J. Kawas, F Garza

IGC Proceedings (1977-2023)

Trace mineral concentrations of soil, forage and serum of range cattle of the northeast Mexico state of Nuevo Leon were determined in both wet and dry seasons of 1992. For each season, collections were made at twenty-four ranches within eleven counties of three regions. A total of 220 soil, 680 forage and 220 blood samples were collected and analyzed. No differences (P<0.05) between regions were obtained for Zinc (28.0 to 34.9 ppm) or Copper (4.4 to 5.4 ppm). Molybdenum concentrations were greater in the northern (2.1 ppm) than in the central (1.6 ppm) or southern (1.5 ppm) regions. Considering the critical levels in forages for Zinc (30 ppm) and Copper (10 ppm) reported by the National Research Council (1984), Zinc concentrations may be marginally deficient, whereas Copper concentrations were deficient in all three regions, in both seasons, and in grasses and woody species.

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Forage-Based Seasonal Dairying In South Louisiana, H A. Deramus, L Labbe, K Ingawa, W A. Atkinson, M J. Simon, J D. Roussel Jul 2024

Forage-Based Seasonal Dairying In South Louisiana, H A. Deramus, L Labbe, K Ingawa, W A. Atkinson, M J. Simon, J D. Roussel

IGC Proceedings (1977-2023)

The effects on the net profit and total milk production were compared using two levels of grain supplementation and forage-only feeding in a program of seasonal dairying in South Louisiana using management intensive grazing. Treatments were 8 kg grain, 4 kg grain, and 0 grain supplementation. Annual ryegrass (Lolium multiflorium) and clovers (Trifolium incarnatum, and T. Alexandrinum) were grazed intensively with 51 multiparous Jersey and Holstein cows in mid-lactation in 1993-1995. Milk production, milk fat, milk protein, and blood urea nitrogen were measured. Milk and protein models were all highly significant for all classes. Daily milk …

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Influence Of Sheep And Goats On The Natural Succession, H D. Matthes, S Demise, M Schubert, H Mohring Jul 2024

Influence Of Sheep And Goats On The Natural Succession, H D. Matthes, S Demise, M Schubert, H Mohring

IGC Proceedings (1977-2023)

A study was conducted to examine the effect of extensively-grazed pasture on the botanical composition. The trails were carried out in the year 1992 to 1995. For the study different breeds of sheep with the stocking rate of 30 sheep with their lambs / 2.6 ha were used. For the mixed-grazing a ratio of 20 sheep and 10 goats with their lambs / 2.6 ha were used. It is not possible to control all problem species with the help of sheepgrazing only. In contrast to that, it was concluded that goats grazed off all problem species quite effectively. Botanical composition …

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Influence Of Different Breeds Of Pigs To The Natural Succession, H D. Matthes, A.C D. Micklich, G Dietl, H Mohring, W Jentsch Jul 2024

Influence Of Different Breeds Of Pigs To The Natural Succession, H D. Matthes, A.C D. Micklich, G Dietl, H Mohring, W Jentsch

IGC Proceedings (1977-2023)

The aim of this study was to find out the effect of pigs on the natural succession. We used 4 different breeds of pigs for our investigations. Because of the grazing behaviour and their rooting activity the total number of plants increased up to 30%. But the vegetation quickly returned to conditions prior to rooting, if the rooting activity fails to happen. Rooting activity of pigs on floodplain soil and following grazing in the next spring after rooting permits seeds of different species of plants to germinate and develop in the plant free areas. These plants often have little chance …

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Road Mitigation Structures Designed For Texas Ocelots: Influence Of Structural Characteristics And Environmental Factors On Non-Target Wildlife Usage, Anna Rivera Roy, Kevin W. Ryer, Md. Saydur Rahman, John H. Young Jr., Richard J. Kline Jul 2024

Road Mitigation Structures Designed For Texas Ocelots: Influence Of Structural Characteristics And Environmental Factors On Non-Target Wildlife Usage, Anna Rivera Roy, Kevin W. Ryer, Md. Saydur Rahman, John H. Young Jr., Richard J. Kline

School of Earth, Environmental, & Marine Sciences Faculty Publications

Roads negatively impact wildlife through habitat fragmentation, loss of habitat connectivity, and wildlife-vehicle collisions, thus road mitigation structures, such as wildlife crossing structures (WCS), wildlife guards (WG), and fencing are commonly used to address this issue all over the world, including in the United States. In South Texas, such structures were built or modified along a State Highway in an effort to address road mortality for the endangered ocelot (Leopardus pardalis) and non-target wildlife species. The goal of this study was to examine temporal changes in wildlife interactions with WCS and WG during and after their construction and …

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Red Harvester Ant, Pogonomyrmex Barbatus, Nests Impact Soil Compaction But Not Temperature In Peri-Urban Habitats Of The Lower Rio Grande Valley, Geovanni Hernandez, Hannah J. Penn, Richard Cano, Lilly Victoria Elliott-Vidaurri, Robin A. Choudhury Jul 2024

Red Harvester Ant, Pogonomyrmex Barbatus, Nests Impact Soil Compaction But Not Temperature In Peri-Urban Habitats Of The Lower Rio Grande Valley, Geovanni Hernandez, Hannah J. Penn, Richard Cano, Lilly Victoria Elliott-Vidaurri, Robin A. Choudhury

School of Earth, Environmental, & Marine Sciences Faculty Publications

Ants are vital ecosystem engineers that can influence soil properties, subsequent soil processes, and associated biota via underground nest construction. Harvester ants consume seeds and are often found in arid areas. They frequently alter the soil chemistry and bulk density of the soils in and around their nest sites. Many species of harvester ants also intentionally remove vegetation around their nest openings, which creates cones or discs of bare soil that may further alter soil temperatures. However, much of the work to study the impacts of harvester ants on soil properties has occurred in shrubland and grassland settings rather than …

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Revealing The Ongoing Speleogenetic Processes In An Underwater Cave Through The Application Of Natural Radionuclides And Stable Isotopes: Case Study From The Hypogene Buda Thermal Karst, Anita Erőss, Katalin Hegedűs-Csondo, Petra Kovács-Bodor, Dénes Szieberth, Ákos Horváth, György Czuppon, Andrea Mindszenty Dr, Szabolcs Leél-Őssy, Judit Mádl-Szőnyi Jul 2024

Revealing The Ongoing Speleogenetic Processes In An Underwater Cave Through The Application Of Natural Radionuclides And Stable Isotopes: Case Study From The Hypogene Buda Thermal Karst, Anita Erőss, Katalin Hegedűs-Csondo, Petra Kovács-Bodor, Dénes Szieberth, Ákos Horváth, György Czuppon, Andrea Mindszenty Dr, Szabolcs Leél-Őssy, Judit Mádl-Szőnyi

International Journal of Speleology

The underwater Molnár János Cave in the hypogene Buda Thermal Karst system (Budapest, Hungary) provides a unique site to study the effects of flowing groundwater and the interplay of fluids of different origin. The aim of the present study is to characterize the groundwater in different parts of the cave with temporal resolution, hence describe the recent speleogenetic processes within the cave. This study uses natural radioisotopes (uranium, radium, and radon) besides stable isotope ratios of oxygen and hydrogen to identify the different fluid components. The results show that the majority of the cave is situated in the flow path …

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Populations Of The Stygobiotic Amphipod Palearcticarellus Pusillus (Martynov, 1930) Maintain Genetic Connectivity Between The Mountain Springs And The Deep Bottom Habitats Of Lake Teletskoye (Altai Mountains, Russia), Ivan Marin, Liubov Yanygina, Svetlana Ostroukhova, Dmitry Palatov Jul 2024

Populations Of The Stygobiotic Amphipod Palearcticarellus Pusillus (Martynov, 1930) Maintain Genetic Connectivity Between The Mountain Springs And The Deep Bottom Habitats Of Lake Teletskoye (Altai Mountains, Russia), Ivan Marin, Liubov Yanygina, Svetlana Ostroukhova, Dmitry Palatov

International Journal of Speleology

The diversity of underground fauna is often associated with the presence of karst areas, which have extensive underground cavities and connecting channels. Non-karst areas, however, make up a larger portion of the planet’ surface, and our understanding of the distribution and dispersal abilities of underground fauna in these areas currently remains limited. During a recent study of the diversity of stygobiotic crustaceans in the mountain streams of the Kurai Mountain Range (Altai, Russia), a small-sized species of crangonyctid amphipod, Palearcticarellus pusillus (Crustacea, Amphipoda, Crangonyctidae) was found in high-altitude springs. This species has been previously known only from deep-water habitats in …

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Infograz: A Data Base For Tropical Grazing Systems, K G. Rickert, J Carter, C K. Mcdonald Jul 2024

Infograz: A Data Base For Tropical Grazing Systems, K G. Rickert, J Carter, C K. Mcdonald

IGC Proceedings (1977-2023)

INFOGRAZ is a prototype of a comprehensive relational database that describes the management of, and stores information from, grazing experiments in northern Australia associated with the wool, beef, and dairy industries. It provides permanent storage and public access for detailed measurements on climate, soil, plants, and animals, which are a valuable resource for future pasture scientists and computer modellers of grazing systems. Thus it will prevent the detailed observations being lost with the passage of time. Verified data from each experiment are stored in tables which can be distributed on CD-ROM, along with procedures to access the data and use …

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The Hydrological Impacts Of Woody Plant Encroachment On Coastal Tallgrass Prairie Of Texas, Zhiwei Guo Jul 2024

The Hydrological Impacts Of Woody Plant Encroachment On Coastal Tallgrass Prairie Of Texas, Zhiwei Guo

LSU Master's Theses

Globally, woody plant encroachment into grassland and savanna ecosystems impacts the hydrological functions of grasslands and associated wetlands. In the coastal tallgrass prairie of Texas, encroachment of woody plants has altered vegetation structure, but the hydrological impacts are poorly understood. In this study, I evaluated and quantified how woody plant encroachment affects hydrological processes on the pimple mounds and inter-mound freshwater marsh, including precipitation partitioning, infiltration in the vadose zone, groundwater recharge, and water volume in the inter-mound marsh. I randomly selected three pimple mounds with woody plants and three pimple mounds with tallgrass w to quantify hydrologic processes. The …

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Effects Of Two Grazing Conditions On The Reproductive Achievement Of Male Alpaca In The Northern Peru Grasslands, C Pinares, E Malpartida, S Cortez Jul 2024

Effects Of Two Grazing Conditions On The Reproductive Achievement Of Male Alpaca In The Northern Peru Grasslands, C Pinares, E Malpartida, S Cortez

IGC Proceedings (1977-2023)

Alpaca have recently been introduced to the northern Peru grasslands (Jalca). Effects of two systems of grazing management, co-grazing (with sheep) under fair grassland condition (CGFC) versus exclusive grazing under good grassland condition (EGGC), upon the reproductive achievement was examined from the 6th to the 16th month of age. Each system involved 20 Huacaya animals, managed by individual herders. Availability of herbage preferred by alpaca (HMA) and animal measurements (herbage intake, liveweight, testicle size, penis release from preputial attachments, plasma testosterone) were monitored monthly. Puberty, judged by the penis release from the preputial attachments, was achieved by 7 …

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Experiences Of Eight Ohio Beef And Sheep Producers With Year Round Grazing, H M. Bartholomew, S L. Boyles, B Carter, E Vollborn, D Miller, R M. Sulc Jul 2024

Experiences Of Eight Ohio Beef And Sheep Producers With Year Round Grazing, H M. Bartholomew, S L. Boyles, B Carter, E Vollborn, D Miller, R M. Sulc

IGC Proceedings (1977-2023)

Livestock producers participated in a demonstration project to extend the grazing season and evaluate dormant forage quality and yield. Differences were not detected in yields among forage species but yield differences existed among sites. Yield estimates did not change over time across all forage species but some sites were only able to participate for two months. Producers utilizing fescue beyond November had reductions in herbage mass. Crude protein, available crude protein, acid detergent fiber, and neutral detergent fiber content differed among forage species and sites. Energy and lignin content were similar for all forage species and sites. Sodium and copper …

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Forage Production Of Irrigated Lecerne- Grass Mixtures Grazed By Sheep, M L. Enrique, D P. Minon Jul 2024

Forage Production Of Irrigated Lecerne- Grass Mixtures Grazed By Sheep, M L. Enrique, D P. Minon

IGC Proceedings (1977-2023)

The forage production and botanical changes of lucerne cultivars in pure stands and in grass mixtures were studied in a split-plot experiment with irrigation and sheep grazing. The non dormant lucerne cultivars (Medicago sativa) CUF 101, Monarca SPINTA, P 30 and common were the main plots, and tall fescue (Festuca arundinacea), canarygrass (Phalaris aquatica), cocksfoot (Dactylis glomerata), tall wheatgrass (Thynopirum ponticum) and prairie grass (Bromus catharticus) were the subplots. The experiment was grazed 3, 6 and 4 times during 3 years. Total yield was similar for all lucerne …

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Oat Grazing: Forage Composition And Supplementation Response, A J. Freddi, M J. Arzadun, A A. Pissani, P Sastre Jul 2024

Oat Grazing: Forage Composition And Supplementation Response, A J. Freddi, M J. Arzadun, A A. Pissani, P Sastre

IGC Proceedings (1977-2023)

Oat forage (Avena sativa), which has low soluble carbohydrates (SC) and high soluble protein (SP) content, can reduce liveweight gain of grazing animals; supplementation with grain and low degradability protein may serve to counteract the effect. A grazing trial was carried out on two soils with different nitrogen (NO3 -) availability, from 16 April 1994 to 6 September 1994. Steers were randomly allocated to 3 treatments: low nitrogen (LN), high nitrogen (HN) and high nitrogen with supplementation (HNS). Forage of LN showed lower SP (p<0.05) during the first month of grazing, and higher SC (p<0.05), than HN during the first two months of the trial. Animal liveweight gain was: 892, 909 and 775 g/an/day for LN, HNS and HN, respectively, with animals in HN of significantly lower liveweight gain (p<0.05). Under the conditions of this trial, animals grazing on oat forage with lower SC and higher SP had lower liveweight gain and responded to supplementation.

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Native And Introduced Forage Systems For Cow-Calf Production, S W. Coleman, W A. Phillips, J D. Volesky Jul 2024

Native And Introduced Forage Systems For Cow-Calf Production, S W. Coleman, W A. Phillips, J D. Volesky

IGC Proceedings (1977-2023)

The objectives of this study was to compare a highly productive introduced warm-season perennial grass to native range for cowcalf production over two years. Three systems, 1) native range with pelleted soybean or cottonseed meal as winter protein supplement (NC); 2) native range with wheat pasture (NW); and 3) Plains Bluestem with wheat pasture (PB) were compared. Protein supplements were given twice weekly and cows grazing wheat pasture were allowed 6 hrs to graze. Cows on NW were heavier with higher condition at breeding in the spring of 1994 than those on NC and cows on PB were heavier and …

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Rotational Stocking And Soil Nutrient Distribution On Hawaiian Grasslands, B W. Mathews, J P. Tritschler, L E. Sollenberger Jul 2024

Rotational Stocking And Soil Nutrient Distribution On Hawaiian Grasslands, B W. Mathews, J P. Tritschler, L E. Sollenberger

IGC Proceedings (1977-2023)

A naturalized kikuyu (Pennisetum clandestinum Hochst. ex Chiov.) grassland was grazed by heifers (Bos taurus) for 2 years to determine the effects of two rotational stocking methods (short vs. long grazing periods) on soil N, P, K, Ca, Mg, and S distribution in paddocks with natural shade. Additionally, kikuyugrass-greenleaf desmodium (Desmodium intortum Urb.) paddocks were used to evaluate soil nutrient distribution in rotationally stocked paddocks (long grazing periods) without shade. In the study with shade, soil N, P, and K distribution did not differ between stocking methods. These nutrients accumulated within 15 m of shade, but did not …

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Relationship Between Height And Sward Quality In Rotational Dairy Systems, M R. Mosquera-Losada, A Gonzalez-Rodriguez Jul 2024

Relationship Between Height And Sward Quality In Rotational Dairy Systems, M R. Mosquera-Losada, A Gonzalez-Rodriguez

IGC Proceedings (1977-2023)

Height is a good guide for management in dairy systems.Intake by dairy cows depends on amount offered and quality of pasture and for this reason a relationship between that offered and pasture quality with height should be studied. The experiment was conducted in NW of Spain with three different stocking rates in dairy systems. A lower quality sward was found in the taller offered pasture as indicated by its higher ADF and lower CP percentages. Total sward ADF (kg x ha-a) was higher in taller offered pasture, which indicated a lower pasture quality, however the total CP was positively related …

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Non-Destructive Methods For The Estimation Of Sward Production, M R. Mosquera-Losada, A Gonzalez-Rodriguez Jul 2024

Non-Destructive Methods For The Estimation Of Sward Production, M R. Mosquera-Losada, A Gonzalez-Rodriguez

IGC Proceedings (1977-2023)

Two non- destructive methods of grass production were compared: grassmeter and sward stick, in order to find an equation for transforming one into the other in dairy rotational systems. Linear, logarithmic and quadratic equations were fitted to the data. Linear equation was preferred by simplicity. General equations which included all the year periods showed no differences between sward stick and grassmeter. A detailed study of the different phenology states showed lower heights with grassmeter than with the sward stick method, which should take into account grazing management height recommendations.

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Chemical And Morphological Characterization Of Airborne Particulate Matter At The Jackpile-Paguate Mine, Pueblo Of Laguna, New Mexico: Implications For Potential Metals Exposure, Andreanna C. Roros Jul 2024

Chemical And Morphological Characterization Of Airborne Particulate Matter At The Jackpile-Paguate Mine, Pueblo Of Laguna, New Mexico: Implications For Potential Metals Exposure, Andreanna C. Roros

Earth and Planetary Sciences ETDs

The inhalation of windblown particulate matter (PM) derived from abandoned uranium mines (AUMs) is a potential environmental health risk to Native American communities that live in proximity to these sites. However, the aeolian transport of metal-bearing PM from AUMs, as a potential exposure pathway, has not been investigated in any detail. In this study, we sampled airborne particulate matter within the Jackpile Mine located on the lands of the Pueblo of Laguna, New Mexico using passive sampling methods to understand the characteristics of dust within the mine site. The objective was to determine the elemental concentrations, mineralogy, and morphology of …

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Proterozoic Tectonic Evolution Of The Lower Granite Gorge, Grand Canyon, Arizona: A Middle Crustal Record Of Multiple Orogenic Pulses, John M. Bailey Jul 2024

Proterozoic Tectonic Evolution Of The Lower Granite Gorge, Grand Canyon, Arizona: A Middle Crustal Record Of Multiple Orogenic Pulses, John M. Bailey

Earth and Planetary Sciences ETDs

The well-exposed basement transect in the Lower Granite Gorge (LGG) of western Grand Canyon provides a middle-crustal record of suturing crustal blocks during the Proterozoic accretionary history of southwestern Laurentia. Orogenic evolution included at least three stages: (1) subduction-related ~1.75-1.72 Ga volcanic arc magmatism, turbidite deposition, and suturing of arc terranes with different crustal thicknesses; (2) intense northwest-southeast crustal shortening at ca. 1.71-1.68 Ga to form the Vishnu Mountains during the Yavapai orogeny; (3) dextral strike-slip shear zones development at ~1.4 Ga during long-term crustal residence and slow cooling above ~250 °C (~10 km) until ~1.3 Ga. Final cooling from …

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Sulfur Sequestration In Anhydrite Through Alteration Of Calcic Wall Rock, Lexi Kenis Jul 2024

Sulfur Sequestration In Anhydrite Through Alteration Of Calcic Wall Rock, Lexi Kenis

Earth and Planetary Sciences ETDs

Heterogeneous gas-solid reactions are suggested as a potential mecha-
nism for sequestering gaseous sulfur through the alteration of calcic wall
rocks. This study explores the concept of a “hierarchy of reactions” pro-
posed by Giggenbach (1987), outlining the interplay between gas components
and redox-related minerals in volcanic wall rocks. Mt. Pinatubo provides a
more felsic composition and more oxidizing conditions compared to previ-
ously studied volcanoes, Kudryavy and Erta Ale (Henley and Fischer, 2021),
and Lascar a more oxidizing case with a similar composition. By employing
thermodynamic models and synthetic melt experiments, evaluations of effi-
ciency of sulfur sequestration across …

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Impacts Of Morphological Changes On Water Residence Times In River Deltas, Md. Muzahidul Islam Jul 2024

Impacts Of Morphological Changes On Water Residence Times In River Deltas, Md. Muzahidul Islam

LSU Master's Theses

Coastal river deltas possess substantial socioeconomic and ecological importance and are expected to encounter increasing risks because of global climate change. The long-term sustainability of many deltaic systems is at risk due to a mix of natural and human-induced factors. Deltas are characterized by their continuous reconfiguration of channels and floodplains due to allogenic and autogenic processes. Sediment supply and composition, sea level rise, vegetation, river discharge, and human development may affect the morphological evolution of river deltas. The timescales and patterns of hydrological transport within a river delta are important indicators of ecological function. One such metric, the water …

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Formation And Development Of The Center For Grassland Studies At The University Of Nebraska, M A. Massengale Jul 2024

Formation And Development Of The Center For Grassland Studies At The University Of Nebraska, M A. Massengale

IGC Proceedings (1977-2023)

The Center for Grassland Studies was formed at the University of Nebraska in 1994 to implement focused interdisciplinary research, educational, and service programs and activities that emphasize the role of grasslands as a natural resource and conservation measure and that enhance the efficiency, profitability, sustainability, and aesthetic value of grasslands, wetlands, and turf. Although the Center is still in a developmental stage, it appears to be accomplishing those objectives.

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The Transformation Of Greek Grasslands Under The Impact Of Socio-Economic Factors, R Thanopoulos Jul 2024

The Transformation Of Greek Grasslands Under The Impact Of Socio-Economic Factors, R Thanopoulos

IGC Proceedings (1977-2023)

The impact of socio-economic factors on the transformation of Greek grasslands is examined. Factors like urbanisation, migration, collapse of traditional way of life, social pressure for land distribution, intensification of agriculture shaped the evolution of grasslands. Thus, these factors should be taken into consideration for the planning of grasslands management.

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Early Frasnian (Upper Devonian) Genundewa Event In The Bolshaya Nadota River Section Of The Subpolar Urals (Russia), Marina Soboleva, Denis Gruzdev, Dmitry Sobolev, Andrey Zhuravlev Jul 2024

Early Frasnian (Upper Devonian) Genundewa Event In The Bolshaya Nadota River Section Of The Subpolar Urals (Russia), Marina Soboleva, Denis Gruzdev, Dmitry Sobolev, Andrey Zhuravlev

Turkish Journal of Earth Sciences

Evidence of the Frasnian Genundewa Event at the FZ 2 – FZ 3 boundary interval has been detected in the facies of the isolated carbonate platform in Subpolar Urals. The preserved traces of the Genundewa Event represent micritic microlaminated carbonates, which manifests a short-term deepening episode in an extremely shallow water background. From the onset of this deep-water deposition there is a dominance of Polygnathus, Ancyrodella, and Mesotaxis whereas in the underlying shallow water deposits, the genus Polygnathus clearly predominated. No specific features of the Genundewa Event were observed in the C-isotope record. The mean δ13Ccarb value is approximately 2‰ …

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Carbonate And Organic Proxies And The Impacts Of Climate On Lake Systems: Paleoclimate Interpretations From Lake Chalco, Mexico, Aria Holmes Jul 2024

Carbonate And Organic Proxies And The Impacts Of Climate On Lake Systems: Paleoclimate Interpretations From Lake Chalco, Mexico, Aria Holmes

Earth and Planetary Sciences ETDs

This project incorporates several lines of evidence to better understand the climate at Lake Chalco. Chapter 1 utilizes oxygen isotopes from carbonates and show that the Inter Tropical Convergence Zone varies on primarily glacial and millennial timescales; precession is not observed. These data indicate glacials periods were shallower and interglacials were wetter periods at Lake Chalco. Chapter 2 studies carbon, nitrogen, C/N, and TOC proxies and finds that the lake conditions during the glacials and interglacials are primarily a mixed algal-macrophyte-terrestrial organic matter. Deviations show that the lake during the interglacials had more algal organic matter- reflecting influxes of nutrients …

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