Soil Science Commons^™

Post-Harvest Eucalyptus Residue Removal Reduces Soil Aggregation And Biological Activities In Central-West Brazil, Karla Nascimento Sena, Thaís Soto Boni, Kátia Luciene Maltoni, Ana Maria Rodrigues Cassiolato, Engil Isadora Pujol Pereira

School of Earth, Environmental, & Marine Sciences Faculty Publications

Tree residue removal from Eucalyptus plantations after timber harvest can reduce soil functioning by reducing the organic matter input. To assess the effects of residue management systems (RMS) on soil aggregation, carbon (C) and nitrogen (N) content, and biological activities, a field trial was conducted in a commercial Eucalyptus plantation (loamy sand soil) in Mato Grosso do Sul, Brazil. The study assessed three RMS: cut-to-length (CTL), tree-length (TL), and bare litter (BL), respectively. After 21 months, undisturbed soil samples were collected and physically isolated into three aggregate-size fractions: large macroaggregates (LM), medium macroaggregates (SM), and microaggregates (MI). Results showed that …

Adaptation, Compatibility And Acceptability Of Grass-Legume Pastures In The Andean Region Of Colombia, E. Cárdenas, E. Castro

IGC Proceedings (1977-2023)

In Colombia, the specialised dairy production system is located in the high altitude Andean region. Its main feed resources are pure stands of Pennisetum clandestinum or/and Lolium spp. Nevertheless, the present market conditions require highly competitive and quality forages year round. These forages should be produced with low inputs (irrigation, fertilisers and agrochemicals) and be resistant to pests and diseases. The objective of this research was to evaluate the adaptation, compatibility and acceptability of introduced forage species for sustainable pasture management.

New Cultivars For High Quality, Persistent Legume-Grass Pastures In The Southern Usa, J. H. Bouton

IGC Proceedings (1977-2023)

In the southern USA one cannot depend on perennial legume-grass pasture systems to have persistently high nutritive quality. 'Jesup' tall fescue, a cultivar with better persistence in the region than 'Kentucky 31', was re-infected with a non-ergot alkaloid producing strain of the Neotyphodium coenophialum fungal endophtye (MaxQ^TM) and found to give persistence equal to Jesup with its endemic strain (E+), but without animal toxins (Bouton et al., 2002). 'Durana' white clover (Bouton et al., 2004) was developed from regional ecotypes of Trifolium repens f. hollandicum germplasm and found to improve animal performance in both E+ and …

Seed Productivity Of Festulolium And Lolium X Boucheanum Varieties, Iveta Gutmane, Aleksandr Adamovich

IGC Proceedings (1977-2023)

Hybrid ryegrasses are intermediate lines between perennial ryegrass and Italian ryegrass as regards growth parameters, productivity and resistance. Good quality and digestibility of forage and higher yield are the main advantages of hybrid ryegrass over perennial ryegrass. Climatic conditions in the Baltic States and North Europe are not favourable enough for ryegrass cultivation but Festulolium is a prospective forage crop for this area (Nesheim, 2000, Adamovich, 2003). Ryegrasses, including hybrid ryegrasses, surpass Festulolium in forage quality. However, Festulolium persistance (resistance, winter-hardiness and, thus, high productivity) are noteworthy. Due to yield quality and competitive productivity, Festulolium may rank equally with timothy …

Comparing Yield And Quality Of Milk From Dairy Cows Fed Stockpiled Annual Ryegrass (Lolium Multiflorum L.) And Cereal Rye (Secale Cereale L.), L. E. Meinhardt, R. L. Kallenbach

IGC Proceedings (1977-2023)

Stockpiling annual ryegrass and cereal rye provides a low cost substitute to hay and creates an excellent source of feed during winter (Kallenbach et al., 2003). In addition to lowering feed costs, grazing increases the conjugated linoleic acid (CLA) content of milk compared to feeding hay. Previous research suggested that forage species might differ in their ability to alter milk CLA content during the growing season (Wu et al., 1997). However, research is needed to determine if different forage species used for winter and early spring grazing impacts the CLA content of milk. The objective of this experiment …

A Grazing Method To Solve The Lack Of Pastures In The Dry Season Of Tropical Areas With Long Periods Of Drought, R. O. Martinez, R. Tuero, M. F. Díaz

IGC Proceedings (1977-2023)

Rotational grazing systems used in tropical areas in Latin America do not solve the great difference in pasture availability between the dry and the rainy season. The main studies on rational grazing (Voisin, 1963) were performed in temperate areas where the deficit of feeds in winter may only be solved with external feeds such as forages and silages produced out of the grazing system. The objective of this work was to demonstrate that it is possible to maintain pasture availability throughout the year with the use of a Pennisetum purpureum clone (Cuba CT-115) adapted to grazing (Martínez et al., …

Breeding And Evaluation Of Forage Soyabeans, T. E. Devine

IGC Proceedings (1977-2023)

The principal use of soyabean in the US in the early 1900s was as livestock forage. Soyabeans are less expensive to establish than small seeded perennial legume forages and can provide legume protein after winter killing of perennial legumes. Soyabean can improve production distribution by vigorous growth during the hot summer season when traditional perennial legumes are less productive.

Effect Of Utilisation Date On The Yield And Quality Of A Semi-Natural Grass Stand In Winter, Jiří Skládanka

IGC Proceedings (1977-2023)

Prolongation of the grazing period into the winter season reduces the costs of feedstuffs for dry cows. To enable the use of pastures in winter it is necessary to carry out the last cut or grazing cycle in June or July and to postpone the last grazing until the first week of August. (Opitz von Boberfeld, 1997). The time of the last utilisation in summer influences the yield and quality of herbage during the winter season (Bartholomew et al., 1997). This research studied changes in yield and quality of a semi-natural grass stand in autumn and in winter following …

Annual Forage Legume Response To Herbicides Labelled For Lucerne Establishment, Twain J. Butler, R. Bow, J. P. Muir

IGC Proceedings (1977-2023)

Weed competition reduces stand establishment, thus lowering forage production and quality. However, there are no herbicides labelled for annual legume establishment, despite several labelled for the establishment of lucerne (Medicago sativa). Some of these may be useful in the establishment and production of annual forage legumes. Lucerne herbicides have greater potential for use on other legumes, since they have grazing and feeding clearance. The objective of this paper is to summarize annual legume yield response trials to herbicides labelled for lucerne establishment.

Development And Evaluation Of An Automated Tactical Tillage Tool To Control Weeds In Row-Crop Production Systems, Grace Mccormick Friday

Theses and Dissertations

Weed control is an integral part of a successful overall production strategy in row- cropping systems and has the potential to reduce or eliminate yield losses that negatively affect profitability. Timely and correctly selected herbicide applications are the major keys for effective weed control in a majority of instances. However, there are negative factors that contribute to ineffectiveness and weed escape issues that currently lack viable options for management. Sparsely populated late-season weeds that emerge after lay-by herbicide applications and weeds that have become tolerant and resistant to traditional herbicide chemistries are of greatest concern. Historically, these weeds would have …

Hymenachne Amplexicaluis [(Rudge) Nees] Genetic Resources Collection In México, A Suitable Grass For Flood Plains In Tropical Areas, J. F. Enriquez-Quiroz, A. R. Quero-Carrillo, J. Perez-Perez, A. Hernandez-Garay, E. Garcia-Moya

IGC Proceedings (1977-2023)

Hymenachne amplexicaluis [( Rudge ) Nees; 2n= 2x= 24; Azuche, West Indian marsh grass] is a native Central and South America C₃ grass that grows well under intermittent flooding conditions. It produces good seed set and stolons to thrive on new areas assuring its survival, combined with an efficient N metabolism to promote vigorous new growing leaves and tillers (Antel et al., 1998). Azuche is a dual attribute species when introduced to new areas; it has valuable forage attributes but also is a potential weed (Hill, 2000). As Azuche is a native species, one must deal with in …

Critical Analysis Of Tropical Forage Breeding In Brazil, J. A. Usberti Jr., P. B. Alcantara

IGC Proceedings (1977-2023)

Forage grasses account for 90% of the Brazilian forage seed market while the genera Brachiaria, Panicum and others are responsible for 85, 10 and 5% of the traded grass seeds, respectively. Most of the forage grass and legume cultivars available for sowing in Brazil were selected in germplasm banks during the last 20 years, while few of them were derived from artificial crossings, followed by selection for desirable forage traits. The selection of new genetic materials in germplasm banks (exploitation of naturally-occurring genetic variability) is still feasible but the chances of success are decreasing through time. From now on, …

Effects Of Land Use On Soil Microbial Communities In Tropical Montane Forests Of Malaysian Borneo, Yang Kai Tang

Graduate Theses and Dissertations

Land use, such as logging and forest conversion to agriculture, can modify soil physicochemical and biological properties, and affect soil health. To understand how land use change can impact soil properties and canopy structure, we used a land use gradient in Malaysian Borneo consisting of six sites, including old growth forests, mixed forests, and agriculture fields. Specifically, we aimed to answer the following questions: (1) How do soil physicochemical properties vary across land use types? (2) Does bacterial diversity and composition vary across different land use types? (3) Does fungal diversity and composition vary across different land use types? We …

Impacts Of Preferential Flow On Tc-99and Np-237 Vadose Transport In Soils At The Savannah River Site, Josh Parris

All Theses

Since the 1950s, the United States has produced approximately 90,000 metric tons of spent nuclear fuel (SNF) (Office of Nuclear Energy, 2022); however, no long-term storage solutions are available. Technecium-99 and neptunium-237, two fission products found in SNF, readily form highly mobile species in oxidizing conditions (Hu, 2008; Bondietti, 1979) and have respective half-lives of 2.13 x 10⁵ and 2.14 x10⁶ years (Hu, 2010). Considering these characteristics, ⁹⁹Tc and ²³⁷Np are two risk-driving isotopes found in SNF storage. The process of macropore-facilitated preferential flow, transport through cracks within a soil matrix, has been recognized to increase …

Net-Zero Target And Emissions From Land Conversions: A Case Study Of Maryland's Climate Solutions Now Act, Philip Hutton

All Theses

Many climate change “solution” plans include net-zero goals, which involve balancing the anthropogenic greenhouse gas emissions (GHG) with their removal. Achieving net-zero goals is particularly problematic for soils because they are often excluded from GHG inventories and reduction plans. For example, Maryland’s Climate Solutions Now Act (Senate Bill 528) put forward a target of net-zero emissions by 2045. To achieve these goals, the state of Maryland (MD) needs to quantify GHG emissions. Soils are currently excluded from MD’s GHG assessments. This study examines the challenges in meeting net-zero goals by using carbon dioxide (CO₂). The current study quantified …

Interactive Effects Of Fungal Community Structure And Soil Moisture On Wyoming Big Sagebrush Performance, Arden Marlene Engel

Boise State University Theses and Dissertations

Large swathes of the North American sagebrush steppe have been converted to grazing and agricultural use. Remaining fragmented areas are threatened by invasive annual grasses and associated perpetuation of increased fire frequency, with efforts to restore sagebrush after fire largely unsuccessful. Lack of success may be due, in part, to poor interactions between sagebrush seed sourced from distant locations and unfamiliar soil fungi.

A greenhouse experiment was designed to evaluate effects of soil fungal community composition on sagebrush reestablishment by answering: (1) How does inoculation with ‘coevolved’ versus ‘foreign’ fungal inoculum impact sagebrush fitness? (2) How does moisture availability modify …

Soil Water Use Efficiency Under Integrated Soil Management Practices In The Drylands Of Kenya, Nathan O. Oduor, Monicah Mucheru-Muna, Jayne Njeri Mugwe, Isaya Sijali, George Nyabuga, Daniel Njiru Mugendi

Graduate School of Media and Communications

Soil moisture scarcity and soil fertility decline in the drylands contribute to declining crop productivity. The possible synergistic effects of integrating soil & water conservation, and soil fertility management practices on soil moisture, and hence water use efficiency (WUE) in the drylands of Tharaka-Nithi County in Kenya was assessed. The experiment was laid in a three by three split plot arrangement, with four replications, for four cropping seasons. Minimum tillagewith mulch, tied ridges, and conventional tillage formed the main plot factors. The sub-plot factors included animal manure plus fertilizer at 120, 60, and 30 N kg ha−1. There was significant …

Differentiating Biotic Vs. Abiotic Co2 In The Formation Of Pedogenic Carbonate In Agriculture And Natural Dryland Soils, Valeria Isabel Molina

Open Access Theses & Dissertations

Drylands, characterized by low and sporadic precipitation, require irrigation for crop growth. However, irrigation practices can lead to salt accumulation in soil due to high evaporation rates and reduced leaching. In addition to loading salts to soil, irrigation promotes the accumulation of secondary calcite. In natural systems, the formation of pedogenic carbonate (secondary calcite, CaCO3) is critical, impacting the soil properties hydrologically and biogeochemically, and modifying the global carbon cycle over geological time, albeit at a lower rate. In agricultural sites, irrigation water supplies HCO3- and Ca2+, accelerating the rates of CaCO3 formation and releasing abiotic CO2. This study investigated …

Characterizing Spatial Variability In Soil Co2 Fluxes In The Chihuahuan Desert Using Geostatistical Techniques, Viridiana Orona

Open Access Theses & Dissertations

Spatial variability in soil CO2 efflux across landscapes is an important feature of the â??Critical Zoneâ?? within dryland ecosystems. In dryland critical zones, resources are often distributed in patches or resource islands. Although this is particularly true in natural settings, the significance of spatial variability in CO2 efflux and its patterns also extends to dryland agriculture. In both irrigated and unirrigated systems, human management practices can significantly impact both organic and inorganic carbon cycling processes, highlighting the importance of studying CO2 efflux in these systems. We examined the spatial patterns of soil CO2 efflux and quantified the magnitude and scale …

Temporal Trends In Dryland Soil Carbon Fluxes In Response To Artificial And Natural Pulsed Moisture Events, Briana Alyce Salcido

Open Access Theses & Dissertations

Critical zone processes in drylands play a crucial role in the global carbon cycle, and one of the most important processes is soil CO2 efflux at the interface between soils and the atmosphere, which represents a main pathway for loss of carbon. Predicting the carbon dynamics at this interface is challenging due to the complexity of belowground processes, which include both biotic (soil respiration) and abiotic (calcite precipitation) production of CO2, as well as transport processes that include both diffusive and advective components. In this study, we aimed to investigate the contribution of soil air displacement to soil CO2 efflux …

Daytime Versus Nighttime Sprinkler Irrigation Of Two Urban Crops In A Semi-Arid Climate At High-Elevation, Samikshya Pyakurel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nighttime irrigation scheduling is a longstanding water conservation approach to reduce evaporative losses in Utah's semi-arid, urban landscapes. However, residential demand now exceeds system capacity, and the efficiency of the practice has come under question. Therefore, the objectives of this study include: 1) quantify whether a water savings exists between day and night irrigation with a water balance and energy balance approach, and 2) analyze microclimate and crop quality effects to determine any changes to evaporative demand or plant stress by irrigation timing. In 2019, we established 12 field plots in North Logan, UT (41.77° N, -111.81° W, 1380 m …

Differential Behaviour Of Guineagrass (Panicum Maximum Jacq.) Hybrids, With Different Al+3 Reactions, As To Major Nutrient Translocations To The Leaves, R. S. Paterniani, J. A. Usberti Jr., J. C. Werner

IGC Proceedings (1977-2023)

Most of the Brazilian cultivated pasture fields presents soils with high Al⁺³ levels and liming is economically unfeasible. So, there is an urgent need for grasses with good forage yielding potentials that can withstand Al⁺³ deleterious effects (abnormal root development: short, thick and poorly branched roots, which are unable to effectively translocate water and essential nutrients to the leaves) (Foy, 1984); as a consequence, susceptible genetic materials have their field persistences greatly affected, mainly during drought periods. Researches on Al⁺³ reaction are usually compare supposedly resistant/tolerant genotypes with a resistant control check; doing so, the genotypic effect …

Animal Performance And Productivity Of New Ecotypes Of Brachiaria Brizantha In Brazil, Valéria P. B. Euclides, Manuel C. M. Macedo, Cacilda B. Do Valle, R. Flores, M. P. Oliveira

IGC Proceedings (1977-2023)

Brazil has the competitive advantage of a very dynamic and cost effective animal production system on pastures over other countries. The pursuit for more productive forages that will result in higher quality beef at a lower cost is then justified. Brachiaria is the most important forage genus utilised in Brazil, thus an intense search for new cultivars amongst collected and introduced ecotypes from Africa is underway. Following agronomic evaluation of this material in plots, 8 pre-selected Brachiaria ecotypes were tested under intermittent grazing in paddocks (Euclides et al., 2001). Continuing on the process of cultivar development, two out of …

Development Of A Bahiagrass Paspalum Notatum Flugge With Increased Short-Day Biomass, P. Mislevy, Ann R. Blount, T. R. Sinclair

IGC Proceedings (1977-2023)

Low herbage productivity of subtropical grasses during the short-day winter months of October through to March can place a severe burden on livestock producers in Southeastern U.S. Researchers at the University of Florida (Sinclair et al., 2001) hypothesised that the decrease in forage production might result from physiological dormancy induced by short day length. A study using artificial lights to extend the day length demonstrated that maintaining the day length at 15 hr during the short-day length period increased 'Pensacola' bahiagrass P. notatum Flugge saure Parodi forage yield 122% when compared with normal photoperiod (Mislevy et al., 2001). …

Genetic And Molecular Characterization Of Temperate And Tropical Forage Maize Inbred Lines, B. Alarcón-Zúñiga, E. Valadez-Moctezuma, T. Cervantes-Martinez, T. Cervantes-Santana, M. Mendoza‐Rodriguez

IGC Proceedings (1977-2023)

The livestock feeding in the Central highland of Mexico is based on harvest, grazing and annual forage conservation, being forage maize the most important silage crop (Alarcón, 1995). Even though forage maize is extensively bred in Europe, USA and Asia since 1900's, this started in Mexico in the 1960's, and little is known about the genetic diversity in both agronomic and nutritive value traits. Our breeding program goals are to analyze combining ability of biomass and quality predictors and to study the genetic relationship of inbred lines between lowland tropical and temperate races from Mesa Central, by genetic and molecular …

Preliminary Performance Of Panicum Maximum Accessions And Hybrids In Brazil, Liana Jank, Rosangela M. S. Resende, S. Calixto, M. M. Gontijo Neto, V. A. Laura, Manuel C. M. Macedo, Cacilda B. Do Valle

IGC Proceedings (1977-2023)

Due to the lack of high quality forages adapted to the distinct ecosystems in Brazil, a national network to evaluate 14 accessions, 4 hybrids and 5 commercial standards of Panicum maximum was established in 2002, in 5 regions of Brazil (states of Mato Grosso do Sul, Acre, Rondônia, Minas Gerais and in the Federal District). Staff of the Embrapa Beef Cattle group co-ordinated the network and pre-selected the accessions and hybrids (Jank, 1995; Jank et al., 2001; Resende et al., 2004). We present their performance as to leaf dry matter yield (LDMY) and leaf percentage (LP) obtained from …

Effect Of Applied Biosolids To Bahiagrass Pastures On Copper Status Of Cattle, M. E. Tiffany, L. R. Mcdowell, G. A. O'Connor, N. S. Wilkinson

IGC Proceedings (1977-2023)

When grazing ruminants consume forages high in Mo but adequate in S, there is a risk of molybdenosis (a Mo-induced Cu deficiency). This occurs when Mo, S, and Cu join to form Cu-thiomolybdate complexes in the rumen that are not readily absorbed (Suttle, 1991). High dietary S reduces Cu absorption, possibly due to unabsorbable Cu sulphide formation, independent from its part in thiomolybdate complexes. The use of municipal sludge (biosolids) as a pasture fertiliser is of interest since some contain high Mo which may induce Cu deficiency. The objective of this study was to evaluate the performance and Cu status …

An In Vitro Investigation Of Forage Factors Which Affect The Production Of Conjugated Linoleic Acid And Trans Vaccenic Acid In The Rumen. Ii. Wilting & Cell Damage, Michael R. F. Lee, J. K. S. Tweed, Nigel D. Scollan, R. J. Dewhurst

IGC Proceedings (1977-2023)

Previous studies have shown that cis 9 trans 11 conjugated linoleic acid (CLA) concentrations are higher for summer milk produced from cows grazing fresh pastures than for winter milk when conserved forages are fed (Jahreis et al., 1997). Furthermore, Offer (2003) showed that a similar depression in milk fat CLA occurred if grass was simply cut and fed after a short wilt. This experiment investigated the effect of wilting on the production of CLA and trans vaccenic acid (TVA) in an in vitro rumen simulation, and whether any differences could be related to changes in plant structure. It was …

Effects Of Grassland Management On Herbage Lipid Composition And Consequences For Fatty Acids In Milk, Anjo Elgersma, P. Maudet, I. Witkowska, A. C. Wever

IGC Proceedings (1977-2023)

Herbage provides bulk feed and is the basis for ruminant nutrition. Herbage lipids, especially C18:3, are a major source of beneficial fatty acids (FA) in milk. These desired FA are unsaturated FA such as CLA (conjugated linoleic acid), especially the isomer rumenic acid, and also vaccenic acid, both trans omega-7 FA (Ellen & Elgersma, 2004). As information on lipids in forages is scarce, effects were studied of N application level and regrowth period on the lipid concentration and FA composition of perennial ryegrass (Lolium perenne L.), the most important forage in temperate climate zones. A linear relation had previously …

Effect Of Feeding L-Carnitine And Sunflower Seeds On Cla Content Of Pasture-Fed Beef, S. L. Scott, W. P. Mccaughey, K. E. Buckley

IGC Proceedings (1977-2023)

Pasture finishing enhances levels of conjugated linoleic acids (CLA) in beef lipids (Shanta et al. 1997). CLA (e.g., C18:2 c9, t11), formed during biohydrogenation of polyunsaturated fatty acids (PUFA) in the rumen, can reduce the incidence of heart disease, cancer and obesity in humans. However, pasture finishing cattle can reduce carcass grade. Feeding pasture-fed cattle a high-grain diet for a short finishing period (~60 d) improves grades but may reduce lipid CLA levels. A feeding regime is required that maintains the positive nutritional attributes of pasture-fed beef and improves the meat grade. The objective of this study was to investigate …