Earth Sciences Commons^™

Leaf Blade Selection By Sheep In Kleingrass (Panicum Coloratum L.) Pastures With Different Deferment Periods, P. Sierra, M. S. Cid, M. A. Brizuela, C. M. Ferri

IGC Proceedings (1977-2023)

The winter use of standing dead biomass produced by warm season grasses during the previous growing season may be an alternative to grazing systems in the semi-arid Pampean Region of Argentina. This study evaluated: 1) the effect of different deferment periods on the leaf blade percentage and quality of ‘kleingrass’ (Panicum coloratum L.), a warm season specie recently introduced to that region, and 2) whether rams grazing the vegetation accumulated during these different periods are able to select leaf blades to maintain the quality of their diets. It was generated three treatments by deferment of the forage produced after …

Microhistological Estimation Of Leaf Blade Percentage In Diets From Monoespecific Pastures, P. Sierra, M. S. Cid, M. A. Brizuela, C. M. Ferri

IGC Proceedings (1977-2023)

Although a decrease in the leaf-stem ratio affects the nutritive value of pastures, herbivores can reinforce selection for leaf blades to maintain the quality of their diets. This study evaluated whether the percentage of fragments with furrows in blades could be used to estimate the relative intake of this part of the leaves by herbivores grazing monoespecific pastures. It was worked with vegetation of kleingrass (Panicum coloratum L.) from paddocks with three deferment periods. Blade samples, and different plant part mixtures hand compounded were in vitro digested. The digestion residues were microhistological analyzed determining the number of fragment with …

Evaluation Of Kentucky Bluegrass (Poa Pratensis L.) For Creating Sustainable Grazing Swards In Hokkaido, T. Saigusa, S. Tejima, Y. Ogawa, S. Takahashi

IGC Proceedings (1977-2023)

Kentucky bluegrass (Poa pratensis L.) is generally considered to be a weed in the meadows of Hokkaido. However, a revaluation of this species should be undertaken in terms of its useful characteristics for labor-saving management on farms in marginal areas. The performance of steers (Holstein-Friesian) and botanical composition of Kentucky bluegrass swards were investigated under the stocking methods of set and rotational grazing and compared with timothy (Phleum pratense L.) swards. Kentucky bluegrass was stable over the grazing season under both methods, although timothy decreased rapidly. The average daily gain of steers raised on Kentucky bluegrass swards was …

Numerical Modeling Of Mineralizing Processes During The Formation Of The Yangzhuang Kiruna-Type Iron Deposit, Middle And Lower Yangtze River Metallogenic Belt, China: Implications For The Genesis And Longevity Of Kiruna-Type Iron Oxide-Apatite Systems, Xunyu Hu, Simon Jowitt, Feng Yuan, Guangxian Liu, Jinhui Luo, Yuhua Chen, Hui Yang, Keyue Ren, Yongguo Yang

Geoscience Faculty Research

The Yangzhuang iron deposit is a Kiruna-type iron oxide-apatite (IOA) deposit within the Ningwu mining district of the Middle and Lower Yangtze River Metallogenic Belt (MLYRMB), China. This study applies a numerical modeling approach to identify the key processes associated with the formation of the deposit that cannot be easily identified using traditional analytical approaches, including the duration of the mineralizing process and the genesis of iron orebodies within intrusions associated with the deposit. This approach highlights the practical value of numerical modeling in quantitatively analyzing mineralizing processes during the formation of mineral deposits and assesses how these methods can …

Iron And Manganese Oxidation By Oxyhalogen Species: Implications For Paleoenvironmental Reconstruction On Mars, Kaushik Mitra

Arts & Sciences Graduate Student Theses and Dissertations

As the nearest planetary neighbor with potential earlier habitable conditions, Mars is replete with minerals that hold clues to its past chemistry and evolution of the aqueous systems. Oxidized iron (Fe) and manganese (Mn) minerals on Mars are geochemical markers of such environments in which they formed and record past pH, redox conditions, and intensity of water-rock interaction. Fe and Mn oxides can therefore be used to reconstruct past Martian environmental conditions from settings where aqueous fluids were active. Various processes that form Fe and Mn oxide minerals on Mars have been previously proposed, including chemical oxidation using molecular oxygen …

Petrology, Geochemistry, And Experimental Studies Of Mafic Enclaves And Amphibole At Shiveluch Volcano, Kamchatka, Andrea Elizabeth Goltz

Arts & Sciences Graduate Student Theses and Dissertations

This thesis connects mineralogical, chemical, and physical observables in quenched mafic inclusions from Shiveluch Volcano in Kamchatka and high pressure and temperature experiments to elucidate the water content of primitive magmas at Shiveluch, the timing of magmatic recharge events relative to eruption, and the petrogenetic history of andesites erupted at Shiveluch. Using the petrology of basaltic andesite mafic inclusions erupted from Shiveluch, in Chapter 2, the water content of primitive magmas at Shiveluch is found to be 8-10 wt%, which is two to three times higher than the global average determined by other methods, and the temperature of primitive magmas …

Potassium Isotope Cosmochemistry, Zhen Tian

Arts & Sciences Graduate Student Theses and Dissertations

In Chapter 1, I review the geochemical and cosmochemical properties of potassium (K). Classified as a moderately volatile element, K serves as a robust proxy for understanding the key processes during nebular/planetary evaporation events. I review different mechanisms of volatile depletion among various planetary materials: mass-dependent variations in “nebular” processes; mass-independent variations among different nucleosynthetic sources; or planetary-scale volatile depletion processes. Furthermore, I provide an optimized K purification procedure via ion-exchange chromatography and a high-precision K isotope analysis technique using Neptune plus Multiple Collector Inductively Coupled Plasma Mass Spectrometer (MC-ICPMS) in both “cold plasma” and “dry plasma” methods. I also …

Structural Stability Of Short Latency Alfalfa-Based Pastures In The Humid Pampa, Argentina, R. O. Refi, B. Martín

IGC Proceedings (1977-2023)

The aim of this study was to search the effects of grazing intensity and nitrogen fertilization on the structural stability of a mixed pasture composed by alfalfa (latency group 9), brome grass, tall fescue and white clover, sown in April 1997. Rotational grazing was carried out with dairy cattle with high intensity (HI: up to 3-4 cm) or moderate intensity (LI: up to 8-10 cm), whenever the alfalfa showed basal regrowth. According to a split-plot design, grazing intensities were subdivided to assign three levels of nitrogen fertilization: N0, without fertilization; N1 with 50 kg N/ha per year; and N2 with …

Late Winter Dietary Overlap Among Greater Rheas And Domestic Herbivores On The Argentinean Flooding Pampa, G. Vacarezza, M. S. Cid, F. Milano

IGC Proceedings (1977-2023)

This study evaluates the dietary overlap among greater rheas (Rhea americana L.) sheep and cattle in the Flooding Pampa, Buenos Aires, Argentina during late winter, when is observed the lowest forage availability. The work was carried out with the following forage classes (FC): warm and cool season grasses and forbs (legumes and no-legumes). Diet botanical composition was estimated by microanalysis of faeces. Principal Component Analysis and Kulcyznsky´s index of similarity were used for data analysis. Rhea populations selected diets with higher forb percentages. On the contrary, vegetation structure and their own morpho-physiology conditioned cattle to diets almost exclusively gramineous. …

Beef Calf Production Using Year-Round Grazing On Tropical Grass Pasture In Summer Combined With Cool Temperate Grass Pasture In Winter, Y. Nakanishi, K. Shindou, S. Watanabe, K. Yamamoto, K. Hagino

IGC Proceedings (1977-2023)

Bahiagrass (Paspalum notatum Fluegge) showed a poor quality with low crude protein in summer but blood biochemical levels of grazing beef cows were similar to drylot feeding cows except of concentration of urea nitrogen. Italian ryegrass (Lolium multiflorum Lam) showed very good quality with high crude protein (about 20 percentage) in winter. And so, suckler cows gained live weight in winter and suckling calves were showed very high growth rate (daily gain was about 1.0 kg). Total live weight gains of grazing cows were higher than those of drylot feeding cows. Postpartum reproductive performances of grazing cows were …

Winter Grazing And Feeding Systems In Western Canada, Duane H. Mccartney, V. Baron, J. Basarab, E. Okine, G. Lastiwka, A. Depalme, D. Young

IGC Proceedings (1977-2023)

Beef cow calf producers in Western Canada are looking for methods of extending the grazing season into the winter in order to lower winter feed costs. Dry beef cows were early or late weaned and grazed during the early months of winter on late seeded barley swaths (Hardlum vulgare L.) and compared to cows fed barley silage and free choice barley straw in a feeding yard. The swath grazed barley was late seeded in June and swathed in the silage stage in mid September. Cows successfully swath grazed for three winters from mid November until mid to late February …

Forage Management For Extending The Grazing Season, David W. Koch, C. M. Lux, J. W. Flake

IGC Proceedings (1977-2023)

Studies were conducted to determine ways to extend grazing season with forages adequate to meet the needs of grazing animals and to reduce the cost of livestock production. Perennial grasses were swathed, windrowed and left in the field until they were winter-grazed with bred heifers. Corn (Zea mays L.) was stockpiled for winter grazing with lambs and ewes. Windrowed grasses increased in acid detergent fiber (ADF) and neutral detergent fiber (NDF) compared with stored hay, but crude protein content, heifer weight gain and body condition change was similar for both forages. An economic value of $218 ha^-1 from …

Replication Data For: Experimental And Numerical Study Of Evaporation From Wavy Surfaces By Coupling Free Flow And Porous Media Flow, Bo Gao, Kathleen Smits

Earth & Environmental Sciences Datasets - Archive

The macroscale roughness of the soil surface has significant influences on the mass/energy interactions between the subsurface and the atmosphere during evaporation. However, most previous works only consider evaporation behavior from flat surfaces. Based on experimental and numerical approaches, the goal of this work is to provide a framework for the understanding of the mechanisms of evaporation from irregular soil surfaces at representative elementary volume scale. A coupling free flow-porous media flow model was developed to describe evaporation under nonisothermal conditions. For simplicity, sinusoidal-type wavy surfaces were considered. To validate this modeling approach, an experiment using an open-ended wind tunnel …

Replication Data For: Evaporation From Undulating Soil Surfaces Under Turbulent Airflow Through Numerical And Experimental Approaches, Bo Gao, Kathleen Smits, John Farnsworth

Earth & Environmental Sciences Datasets - Archive

Evaporation from undulating soil surfaces is rarely studied due to limited modeling theory and inadequate experimental data linking dynamic soil and atmospheric interactions. The goal of this paper is to provide exploratory insights into evaporation behavior from undulating soil surfaces under turbulent conditions through numerical and experimental approaches. A previously developed and verified coupled free flow and porous media flow model was extended by incorporating turbulent airflow through Reynolds-averaged Navier–Stokes equations. The model explicitly describes the relevant physical processes and the key properties in the free flow, porous media, and at the interface, allowing for the analysis of coupled exchange …

Replication Data For: Effect Of Varying Atmospheric Conditions On Methane Boundary-Layer Development In A Free Flow Domain Interfaced With A Porous Media Domain, C. T.K.K. Deepagoda, Kathleen Smits

Earth & Environmental Sciences Datasets - Archive

Mitigation of atmospheric emission of methane from leaky underground infrastructure is important for controlling the global anthropogenic greenhouse gas burden. Overexposure to methane may also cause occupational health problems in indoor/outdoor environments at the local scale. Subsurface soil conditions (e.g. soil heterogeneity) affect methane migration in soils while near-surface atmospheric boundary conditions (e.g. wind and temperature) affect off-site emissions across the soil-atmosphere interface. This study investigated the above-surface methane concentration boundary-layer development under different soil conditions (homogenous and layered) and atmospheric boundary controls (wind and temperature). A series of controlled bench-scale experiments was conducted using an open-loop boundary-layer wind tunnel …

Replication Data For: Thermal Conductivity Of Binary Sand Mixtures Evaluated Through Full Water Content Range, Benjamin Wallen, Kathleen Smits

Earth & Environmental Sciences Datasets - Archive

A soil's grain-size distribution affects its physical and hydraulic properties; however, little is known about its effect on soil thermal properties. To better understand how grain-size distribution affects soil thermal properties, specifically the effective thermal conductivity, a set of laboratory experiments was performed using binary mixtures of two uniform sands tightly packed with seven different mixing fractions over the full range of saturation. For each binary mixture, the effective thermal conductivity, λ, capillary pressure, hc, and volumetric water content, θ, were measured. Results demonstrated that the λ–θ relationship exhibited distinct characteristics based on the percentage of fine- and coarse-grained sands. …

Replication Data For: Characterization Of Grain-Size Distribution, Thermal Conductivity, And Gas Diffusivity In Variably Saturated Binary Sand Mixtures, C. T.K.K. Deepagoda, Kathleen Smits

Earth & Environmental Sciences Datasets - Archive

Characterization of differently textured porous materials, as well as different volumetric porous media mixtures, in relation to mass and heat transport is vital for many engineering and research applications. Functional relations describing physical (e.g., grain-size distribution, total porosity), thermal, and gas diffusion properties of porous media and mixtures are necessary to optimize the design of porous systems that involve heat and gas transport processes. However, only a limited number of studies provide characterization of soil physical, thermal, and gas diffusion properties and the functional relationships of these properties under varying soil water contents, especially for soil mixtures, complicating optimization efforts. …

Biodiversity And Fire In Shortgrass Steppe, Paulette L. Ford

IGC Proceedings (1977-2023)

Effects of fire at two levels of intensity on beetle diversity in shortgrass steppe were examined. The experimental design was completely randomized, with 3 treatments and 4 replicates per treatment. Treatments were two levels of fire 1) dormant-season fire (relatively hot), and 2) growing-season fire (relatively cool), and unburned plots. The response variables were arthropod species richness and abundance. The intermediate disturbance hypothesis predicts that maximum species richness occurs at intermediate levels of disturbance. Data obtained in this study support that prediction. Species richness was higher on plots of intermediate fire intensity than the more intensely burned plots, and almost …

Mechanization: Planning And Selection Of Equipment, C. A. Rotz

IGC Proceedings (1977-2023)

The planning and selection of equipment for harvest and handling of forage crops can greatly impact the performance and profitability of a farm. The type and size of equipment used affects the harvested yield and nutritive value of the forage crop as well as production costs. Through interactions with other parts of the farm, these effects can impact market value of the forage, animal intake and performance, delays in other farm operations, other production costs, and ultimately farm profit. Standard procedures and relationships have been developed for determining the most appropriate equipment for a given production system. Because of the …

Conserved Forage (Silage And Hay): Progress And Priorities, R. E. Muck, K. J. Shinners

IGC Proceedings (1977-2023)

Forage conservation permits a better supply of quality feed when forage production is low. While haymaking and ensiling have been practiced for generations, research is still needed to 1) understand the processes affecting quality during harvesting and storage and 2) develop practical means to minimize losses and enhance quality.

Several trends in harvesting forages for silage are notable. Kernel processing of maize, once confined to Europe, has become popular in North America. Self-propelled forage harvesters have a larger share of the market due to more contract harvesting and larger farms. Larger harvesters, rakes and mergers help improve productivity and forage …

Mercury Emissions From Iron Mining And Copper Mining In The Upper Peninsula, Michigan, Ahmed Al Rahbi

Honors Theses

The wealth in the Upper Peninsula of Michigan has been intimately linked with mining, particularly the extraction of iron and copper. Iron was deposited in the Upper Peninsula 1.9 billion years ago (Gogebic and Ranges, 2020), and copper deposits are believed to be 1.1 billion years old (Blakemore et al., 2016). In the Upper Peninsula, mercury occurs naturally in taconite (iron ore) as elemental mercury (Hg⁰), and within the copper ores as “Mercury copper amalgam” (CuHg). When elemental mercury is released from the ores, it oxidizes in the atmosphere to form inorganic mercury (Hg²⁺) (Risher, 2003; …

Sediment Budgets For Small Salinized Agricultural Catchments In Southwest Australia And Implications For Phosphorus Transport, Robert J. Wasson, David Weaver

Natural Resources Research Articles

Examples of sediment budgets are needed to document the range of budget types and their controls. Sediment budgets for three small agricultural catchments (7.6 to 15.6 km2) in southwestern Australia are dominated by channel and gully erosion, with sheet and rill erosion playing a subordinate role. Erosion was increased by clearing naturally swampy valley floors and hillslopes for agriculture and grazing, and episodic intense rainstorms. The proportion of sediment from channel and gully erosion in the sediment budget appears to be determined by the depth of alluvial fills. Dryland salinization caused by clearing native vegetation has connected hillslopes to channels …

Comparison Of Quality And Production By Different Silage Making Methods Of Barley Cultivated In The Paddy After Rice Harvest, J. S. Shin, E. B. Yoon, M. S. Park

IGC Proceedings (1977-2023)

The objective of this study was to compare whether the productivity and production cost of whole crop barley was affected by silage making methods at early bloom stage in the rice field. In nutritive value, quality and palatability of silage, baled silage making method was a little higher than that of crushed silage making. On the other hand, in terms of dry matter and total digestible nutrient (TDN) production cost, proper work capacity at about 15 ha or more was desirable when making baled silage. In this case, the estimated dry matter production cost and TDN cost per ha was …

Yield, Feeding Value And Ensiling Characteristics Of Clone-13 (Pennisetum Purpureum), Sujatha Premaratne, G. G. C. Premalal, S. M. S. Setunga, J. M. S. Jayawardana

IGC Proceedings (1977-2023)

A study was carried out to find out the effect of frequency of defoliation on yield and feeding value of clone-13 (Pennisetum purpureum) in Sri Lanka. Three frequency of harvesting, namely 45, 60 and 75 days were used and, fresh yield per plot was measured. Sub samples were taken for dry matter determination and proximate analysis. According to results, frequency of harvesting of 60 days can be recommended for clone-13 under no fertilizer regime. In addition, effect of growth stage on ensiling characteristics of clone-13 was also studied. Clone-13 was harvested at 45, 60, 75 or 90 days …

Aerobic Stability Of Grass Silage Mixed With A Range Of Concentrate Feedstuffs At Feed-Out, P. O’Kiely, M. Clancy, E. M. Doyle

IGC Proceedings (1977-2023)

Mixing supplementary concentrates with silage at feed-out could shorten aerobic stability or increase the rate or extent of aerobic deterioration of silage. This experiment quantified such possible effects by twelve contrasting feedstuffs. Four samples (each 6 kg) of unwilted, precision-chop, well preserved grass silage (216 g dry matter (DM) kg^-1 and pH 4.0) were incubated at 20^oC for 6 days in polystyrene containers alone or with the addition of 400 g (solid ingredients were milled) of wheat grain, barley grain, maize grain, molasses beet pulp, citrus pulp, molasses, soybean meal, maize gluten, sunflower meal, rapeseed meal, dry …

Survival Of Escherichia Coli 0157:H7 Added To Grass At Ensiling And Its Influence On Silage Fermentation, P. O’Kiely, C. Byrne, D. Bolton

IGC Proceedings (1977-2023)

Escherichia coli can cause health problems in humans and livestock. It is frequently found in faeces and soil, both of which can contaminate grass harvested for silage-making. To determine the survival of E. coli 0157:H7 during ensilage, and its influence on ensilage, unwilted precision-chop grass was ensiled in laboratory silos with the following additive treatments: (a) no additive, (b) E. coli 0157:H7 (Ec - non-infectious strain, at log₁₀ 4.5 colony forming units (cfu) g^-1), formic acid (FA), and (d) Ec + FA. Silos were stored at 15^oC. Three silos per treatment were opened on days …

Serapan Nitrogen Dan Fosfor Serta Hasil Jagung Yang Dipengaruhi Oleh Aplikasi Pupuk Hayati Dengan Berbagai Teknik Dan Dosis Pada Tanah Inceptisols, Betty Natalie Fitriatin, Muhammad Iqbal Maulana Yusuf, Anne Nurbaity, Nadia Nuraniya Kamaluddin, Meddy Rachmady, Emma Trinurani Sofyan

Jurnal Kultivasi

Upaya meningkatkan unsur hara nitrogen (N) dan fosfor (P) tanah secara berkelanjutan adalah dengan memanfaatkan agen hayati bakteri penambat nitrogen dan bakteri pelarut fosfat. Percobaan pot dilakukan dengan tujuan untuk menentukan teknik aplikasi pupuk hayati dalam meningkatkan kandungan dan serapan hara N dan P serta hasil tanaman jagung pada Inceptisols Jatinangor. Percobaan dilaksanakan di Lahan Percobaan milik Laboratorium Kesuburan Tanah dan Nutrisi Tanaman, Fakultas Pertanian Universitas Padjadjaran. Pupuk hayati yang digunakan merupakan konsorsium bakteri penambat N (Azotobacter chroococcum dan Azospirillum sp.) dan bakteri pelarut P (Pseudomonas malei dan Bacillus subtillis). Percobaan menggunakan Rancangan Acak Kelompok (RAK) dengan sembilan perlakuan dan …

Effects Of Dry Matter Content And Microbial Additive On Tifton 85 (Cynodon Dactylon Ssp.) Wilted Silage Fermentation Parameters, Luiz Gustavo Nussio, F. G. Castro, J. M. Simas, C. M. Haddad, P. Toledo, A. L. Merchan

IGC Proceedings (1977-2023)

The objective of this study was to evaluate the wilting and the addition of a bacterial-enzymatic additive effects on the fermentation parameters of Tifton 85 (Cynodon dactylon spp.) silage. Forage was stored as 326 kg bales wrapped with a plastic film. Treatments consisted of 5 forage dry matter levels (20-30%, 30-40%, 40-50%, 50 -60% e 60 a 70%) without additive and 3 dry matter levels (20-30%, 40-50%, e 60-70%) with additive. Buffered propionic acid solution was sprayed onto 60-70% dry matter bales, prior to wrapping, determining an additional treatment. Core samples were taken at 0, 6, 12 hours …

Dry Matter Losses In Tanzânia Grass (Panicum Maximum, Jacq, Cv. Tanzânia) Silage, M. A. A. Balsalobre, Luiz Gustavo Nussio, P. M. Santos, R. F. Crestana, R. N. S. Aguiar, M. Corsi

IGC Proceedings (1977-2023)

A spring cut of Tanzânia grass (Panicum maximum, Schum, cv. Tanzânia) was harvested (20% DM), in a 60-day regrowth sward. Laboratory silos (20 L) were filled with chopped forage. Nine treatments, in a 3 x 3 factorial arrangement with four replication each. Treatments consisted on the addition of 3 levels of dehydrated and pellet citrus pulp (CP) (0, 5 and 10%- fresh basis) combined with 3 particle sizes (Larger (1), medium (2) and smaller (3)). After 60 days silos were opened, effluent and gas yield was calculated. Reduction in particle size lowered gas losses in silage. Major benefit …

Possibilities To Avoid Growth Of Clostridia And/Or Fungi In Wilted Silage By Use Of Organic And Inorganic Salts, Martin Knický, P. Lingvall

IGC Proceedings (1977-2023)

The hygienic quality of silage will be of great importance in the future as poor quality not only influences the animal production but also the animal health and the food quality. This study examined the impact of mixtures of sodium benzoate (NaB), sodium nitrite (NaN), hexamine (HMTA), sodium propionate (NaP), sodium bisulphite, and propionic acid on low and high wilted clover/grass. The silage (crop wilted to 300 or 600 g DM kg^-1 of fresh weight) consisted of about 50% red clover (Trifolium pratense) and 50% timothy (Phleum pratense) and the study covered 7 additive treatments. …