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Rice Biomass Response To Various Phosphorus Fertilizers In A Phosphorus-Deficient Soil Under Simulated Furrow-Irrigation, Jonathan B. Brye 2024 University of Arkansas, Fayetteville

Rice Biomass Response To Various Phosphorus Fertilizers In A Phosphorus-Deficient Soil Under Simulated Furrow-Irrigation, Jonathan B. Brye

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Wastewater-recovered phosphorus (P), in the form of the mineral struvite (MgNH4PO4⋅6H2O), may provide a sustainable alternative to rapidly decreasing rock phosphate reserves. Struvite can be generated via chemical and/or electrochemical precipitation methods, potentially reducing the amount of P runoff to aquatic ecosystems. The objective of this greenhouse tub study was to evaluate the effects of chemically- and electrochemically precipitated struvite (CPST and ECST, respectively) on above- and belowground plant response in a hybrid rice cultivar (Gemini 214, RiceTec) grown using furrow-irrigation compared to other common fertilizer-P sources [i.e., triple super phosphate (TSP) and diammonium phosphate (DAP)] in a P-deficient silt …


Polygonal Faults In The Austin Chalk: Invariance Of Scale From Mud Cracks To Polygons With Implications Of Structural, Geomorphic And Isotopic Data On Polygonal Fault Geometry And Origin., Kun Shang 2023 Southern Methodist University

Polygonal Faults In The Austin Chalk: Invariance Of Scale From Mud Cracks To Polygons With Implications Of Structural, Geomorphic And Isotopic Data On Polygonal Fault Geometry And Origin., Kun Shang

Earth Sciences Theses and Dissertations

The Cretaceous Austin Chalk contains large numbers of fractures and normal faults whose orientations have been attributed to either regional stresses (e.g., the Balcones fault trend) or, by analogy with the mudrocks, to polygonal faulting resulting from compaction. In this study, we present geomorphic data, field study, and stable isotope data to support that the majority of these faults in North Texas are polygonal. Field-measured fault orientations suggest randomly distributed fault strikes, indicating a polygonal fault structure. Using geomorphologic data (topographic and DEM data) on stream orientations suggests that the polygonal fault patterns are best reflected in the headwater (1st …


Maintaining Grassland Plant Diversity While Controlling Woody Plant Encroachment, James Stubbendieck, Kay L. Kottas, S. J. Tunnell, S. J. Palazzolo 2023 University of Nebraska-Lincoln

Maintaining Grassland Plant Diversity While Controlling Woody Plant Encroachment, James Stubbendieck, Kay L. Kottas, S. J. Tunnell, S. J. Palazzolo

International Grassland Congress Proceedings

The tallgrass prairie region of the United States is a fragmented grassland ecosystem. Much of the 1 to 2% of the remaining prairie is being degraded by invading woody plants, which frequently results in a shift from grassland to woodland. Smooth sumac (Rhus glabra L.), a shrub native to the region, can rapidly increase in density and become dominant in the plant community. Prescribed fire alone is not a constraint to this resprouting species (Stubbendieck et al., 2003). Herbicides are useful tools for managing woody plants in grasslands, but the negative response of desirable plants to herbicides is …


Do Species And Functional Diversity Indices Reflect Changes In Grazing Regimes And Climatic Conditions In Northeastern Spain?, F. de Bello, J. Leps, M. T. Sebastià 2023 Forestry and Technology Centre of Catalonia, Spain

Do Species And Functional Diversity Indices Reflect Changes In Grazing Regimes And Climatic Conditions In Northeastern Spain?, F. De Bello, J. Leps, M. T. Sebastià

International Grassland Congress Proceedings

Understanding the mechanisms that maintain biodiversity in various ecosystems enables the development of management practices that prevent degradation (Canals & Sebastia, 2000). Each diversity index reflects some compositional properties and could be influenced differently by stress and disturbance factors (Magurran, 2004). In this study, we aim to reveal 1) which management practices and environmental factors affect biodiversity in rangelands of northeastern Spain and 2) the relationship between species diversity and functional diversity (SD and FD).


Impact Of Grazing Regimes On Mean Sward Height: Implications For The Management Of Bird Habitats In Agricultural Landscapes, M. Tichit, D. Durant, E. Kernéïs 2023 INRA, France

Impact Of Grazing Regimes On Mean Sward Height: Implications For The Management Of Bird Habitats In Agricultural Landscapes, M. Tichit, D. Durant, E. Kernéïs

International Grassland Congress Proceedings

Grazing in wet grasslands is a key process to manage foraging and nesting habitats for waders. Grazing has positive and negative effects related to the importance of sward conditions for these species and to nest-trampling by cattle. For settlement and nesting, lapwings need a short sward ( ≤ 10cm; see Durant et al., this congress). However, when lapwings settle in early spring, grasslands seldom are grazed yet, due to low soil carrying capacity. We studied the effect of autumn and winter grazing regimes on sward structure in early spring, and the effect of grazing regime in early spring on …


Soil Carbon Sequestration Under Three Years Of No-Till Forage Cropping Systems, D. H. Min, J. D. DeYoung, Richard Leep 2023 Michigan State University

Soil Carbon Sequestration Under Three Years Of No-Till Forage Cropping Systems, D. H. Min, J. D. Deyoung, Richard Leep

International Grassland Congress Proceedings

The effects of reduced tillage on soil organic carbon (SOC) are generally well established (Chan et al., 2002; Cabardella & Elliott, 1992). The effects of different crops are also somewhat understood (Drinkwater et al., 1998). However, many of these studies are done in the laboratory to study the effects of crop residues on SOC. Many forage-based systems have very little crop residue returned to the field. What residue does return is often in the form of manure or compost, which is usually broken down much more rapidly than most crop residues. The objective of this study is to …


Number And Viability Of Seeds Recovered From Faeces Of Ruminant Animals, Alaba O. Jolaosho, Olufemi S. Onifade, O. M. Arigbede, Jimoh A. Olanite, T. O. Akinola 2023 Federal University of Agriculture, Nigeria

Number And Viability Of Seeds Recovered From Faeces Of Ruminant Animals, Alaba O. Jolaosho, Olufemi S. Onifade, O. M. Arigbede, Jimoh A. Olanite, T. O. Akinola

International Grassland Congress Proceedings

Ruminants play a significant role in the dissemination of plant seeds as a result of ingested seeds during grazing on pasture escaping digestion that are voided with the faeces and returned to the seed bank (Russi et al., 1992).


Population Changes Of Invasive Annuals In California Annual And Perennial Grasslands, Richard King 2023 USDA Natural Resources Conservation Service

Population Changes Of Invasive Annuals In California Annual And Perennial Grasslands, Richard King

International Grassland Congress Proceedings

Some non-native annual forbs and grasses can be invasive in California's annual grassland region. Taeniatherum caput-medusae (L.) Nevski and Centaurea solstitialis L. can spread quickly, become nearly monospecific stands, and reduce carrying capacity for livestock and wildlife. Centaurea also can be toxic to horses. Lathyrus hirsutus L. is less invasive, but the seed is toxic to various livestock. Since 1991, the author has raised beef cattle on 16 ha of predominantly annual grassland where these 3 species occur, and a family member has raised cattle on approximately 40 ha of adjacent property. Surface soils in this hilly land are …


The Effect Of Sheep Grazing At Two Stocking Rates On The Seedling Recruitment Of Grassland Forbs, Johannes Isselstein, Markus Kowarschik, S. Bonn, M. Hofmann 2023 University of Göttingen, Germany

The Effect Of Sheep Grazing At Two Stocking Rates On The Seedling Recruitment Of Grassland Forbs, Johannes Isselstein, Markus Kowarschik, S. Bonn, M. Hofmann

International Grassland Congress Proceedings

Limitations for seedling recruitment are major constraints to maintain and enhance plant species diversity in productive grasslands (Bakker & Berendse 1999). Grass sward condition plus species-specific requirements for germination and survival determine the recruitment success. Therefore, a field experiment investigated the establishment of oversown seeds from wildflower forbs in relation to grass sward management.


A Basis For Designing Policies To Optimize Soil Carbon Sequestration In Southeastern Us Grasslands, Joel R. Brown, D. L. Faulkner 2023 USDA National Resources Conservation Service

A Basis For Designing Policies To Optimize Soil Carbon Sequestration In Southeastern Us Grasslands, Joel R. Brown, D. L. Faulkner

International Grassland Congress Proceedings

Increasing the amount of carbon (C) stored in terrestrial ecosystems is an important part of most national greenhouse gas (GHG) management strategies. Among the policy and program options available to achieve increased C sequestration, improved management of grasslands offers an attractive option to both reduce atmospheric concentrations of C and enhance environmental co-benefits (soil quality, water quality, food and fibre production, and wildlife habitat). In the United States, incentives for applying improved land management practices come primarily via federal government conservation programs administered by the United States Department of Agriculture (USDA). While private sector markets offer opportunities to increase the …


The Nature Of Sequestered Carbon In Different Irish Mineral Soils, C. M. Byrne, D. Fay, J. A. Ferreira, M. H. B. Hayes 2023 University of Limerick, Ireland

The Nature Of Sequestered Carbon In Different Irish Mineral Soils, C. M. Byrne, D. Fay, J. A. Ferreira, M. H. B. Hayes

International Grassland Congress Proceedings

Humic substances (HS) provide the major sinks for carbon (C) in soils. Although HS have a degree of resistance to microbial degradation, they are degraded in time. Humin, the HS component in association with the soil mineral colloids, has greatest resistance to degradation. To understand the extent to which soil can be a sink for C it is important to know the soil mineralogy, and to be aware of aspects of the structures of the humic components. Enhanced biological oxidation occurs in soils in long term cultivation. Its effects can be observed by comparing the amounts and compositions of the …


The Effect Of Dairy Cow Genotype On Modelled Greenhouse Gas Emissions Derived From Pasture Based Milk Production Systems, Dan K. Lovett, L. Shalloo, P. Dillon, Frank O'Mara 2023 University College Dublin, Ireland

The Effect Of Dairy Cow Genotype On Modelled Greenhouse Gas Emissions Derived From Pasture Based Milk Production Systems, Dan K. Lovett, L. Shalloo, P. Dillon, Frank O'Mara

International Grassland Congress Proceedings

A three-year systems comparison study was undertaken to see if progressively increasing the genetic potential for milk production of the dairy cow is desirable within pastoral based systems of spring milk production (Kennedy et al., 2002). The production data was inputted into the Moorepark Dairy System Model (MDSM) (Shalloo et al., 2004) to describe the economic, biological and production efficiency of each system. Output was then used to model whole farm greenhouse gas (GHG) emissions (Lovett et al., in press) from the nine systems studied (three concentrate levels by three genotype levels). Only the genotype effects are …


Methane Of Animal Origin In Cattle Fed High Or Low Tannin Sorghum Silage, T. T. Berchielli, S. G. Oliveira, M. P. Pedreira, O. Primavesi, M. A. Lima, R. Frighetto 2023 Ciências Agrárias e Veterinárias, Brazil

Methane Of Animal Origin In Cattle Fed High Or Low Tannin Sorghum Silage, T. T. Berchielli, S. G. Oliveira, M. P. Pedreira, O. Primavesi, M. A. Lima, R. Frighetto

International Grassland Congress Proceedings

The harmful or beneficial effects associated with the presence of tannin in plants depends on its concentration and form. One of these beneficial effects is the reduction of the production of methane in the rumen (Woodward et al., 2001). This study financed by FAPESP aimed to evaluat the effect of diets containing low or high tannin sorghum silage supplements on dry matter intake (DMI) and methane production in cattle.


Field Measurements Of Ruminal Methane Of Cattle Grazing Tropical Grasses, M. P. Pedreira, O. Primavesi, M. A. Lima, R. Frighetto, T. T. Berchielli 2023 Ciências Agrárias e Veterinárias, Brazil

Field Measurements Of Ruminal Methane Of Cattle Grazing Tropical Grasses, M. P. Pedreira, O. Primavesi, M. A. Lima, R. Frighetto, T. T. Berchielli

International Grassland Congress Proceedings

Ruminal methane production represents energy losses from ingested feed that should be utilised to maintain body weight or to generate products. Quantitatively, daily methane production varies according to amount and quality of ingested dry matter (DM), as well as physiological status of the animal.


Hedgerow Systems And Livestock In Philippine Grasslands: Ghg Emissions, D. B. Magcale-Macandog, E. Abucay, R. G. Visco, R. N. Miole, E. L. Abas, G. M. Comajig, A. D. Calub 2023 University of the Philippines Los Baños, Philippines

Hedgerow Systems And Livestock In Philippine Grasslands: Ghg Emissions, D. B. Magcale-Macandog, E. Abucay, R. G. Visco, R. N. Miole, E. L. Abas, G. M. Comajig, A. D. Calub

International Grassland Congress Proceedings

Hedgerow systems are widely adopted in the smallholder farms in the sloping grassland areas of Claveria, Mindanao, Philippines. The system is effective in addressing soil erosion problems and in conserving the topsoil. Gmelina arborea and Eucalyptus deglupta are two fast-growing timber species that are planted in hedgerow systems while maize is planted in the alley areas in between the hedgerows. Livestock holdings are widespread in Claveria, with 74% of the households having livestock. Cattle and carabao are the most common livestock in smallholder farms providing draught power for land preparation and transportation. In hedgerow systems, fodder tree leaves and crop …


The Effect Of Soil Type And Climate On Modelled Greenhouse Gas Emissions Derived From Pasture Based Milk Production Systems, Dan K. Lovett, L. Shalloo, P. Dillon, Frank O'Mara 2023 University College Dublin, Ireland

The Effect Of Soil Type And Climate On Modelled Greenhouse Gas Emissions Derived From Pasture Based Milk Production Systems, Dan K. Lovett, L. Shalloo, P. Dillon, Frank O'Mara

International Grassland Congress Proceedings

The ability of spring calving dairy farmers to exploit herbage production can be limited by soil type and climatic conditions. Previous work, using the Moorepark Dairy System Model (MDSM) (Shalloo et al., 2004) demonstrated differences in terms of biological and production efficiency for two contrasting sites. This study models whole farm greenhouse gas (GHG) emissions (Lovett et al., in press) from two dairy systems, the Moorepark Standard System (MSS, Co. Cork) and the Kilmaley Standard System (KSS,Co. Clare), classified as lower and high rainfall (1025 and 1614 mm yr) and free draining versus poor draining respectively.


Quantification Of Co2 Exchange In Grassland Ecosystems Of The World Using Tower Measurements, Modeling And Remote Sensing, Tagir Gilmanov, M. W. Demment, B. K. Wylie, K. Akshalov, D. D. Baldocchi, L. Belelli, J. A. Bradford, G. G. Burba, R. L. Coulter, W. A. Dugas, W. E. Emmerich, L. B. Flanagan, A. B. Frank, J. Fuher, M. R. Haferkamp, M. B. Jones, D. A. Johnson, T. Laurila, A. Lohila, T. P. Meyers, P. C. Mielnick, J. A. Morgan, M. Nasyrov, C. E. Owensby, M. S. Pekour, K. Pilegaard, A. Raschi, N. Z. Saliendra, M. J. Sanz, P. L. Sims, R. H. Skinner, J. F. Sousanna, A. E. Suyker, L. L. Tieszen, Z. Tuba, R. Valentini, S. B. Verma, E. A. Laca 2023 South Dakota State University

Quantification Of Co2 Exchange In Grassland Ecosystems Of The World Using Tower Measurements, Modeling And Remote Sensing, Tagir Gilmanov, M. W. Demment, B. K. Wylie, K. Akshalov, D. D. Baldocchi, L. Belelli, J. A. Bradford, G. G. Burba, R. L. Coulter, W. A. Dugas, W. E. Emmerich, L. B. Flanagan, A. B. Frank, J. Fuher, M. R. Haferkamp, M. B. Jones, D. A. Johnson, T. Laurila, A. Lohila, T. P. Meyers, P. C. Mielnick, J. A. Morgan, M. Nasyrov, C. E. Owensby, M. S. Pekour, K. Pilegaard, A. Raschi, N. Z. Saliendra, M. J. Sanz, P. L. Sims, R. H. Skinner, J. F. Sousanna, A. E. Suyker, L. L. Tieszen, Z. Tuba, R. Valentini, S. B. Verma, E. A. Laca

International Grassland Congress Proceedings

Grasslands cover significant areas in nontropical regions, perform essential biogeochemical functions and represent important natural and agricultural resource. Nevertheless, in contrast to forests and agroecosystems, no flux measurement-based global summary of their CO2 exchange, sequestration potential, and role in mitigation of the greenhouse effect were available.


The Influence Of Local Immigration And Extinction Of Species On Spatial Heterogeneity Of Vegetation In Semi-Natural Grasslands In Japan, Taisuke Yasuda, Masae Shiyomi, T. Egawa, K. Sei, R. Ishikawa, S. Takahashi 2023 Yamanashi Institute of Environmental Sciences, Japan

The Influence Of Local Immigration And Extinction Of Species On Spatial Heterogeneity Of Vegetation In Semi-Natural Grasslands In Japan, Taisuke Yasuda, Masae Shiyomi, T. Egawa, K. Sei, R. Ishikawa, S. Takahashi

International Grassland Congress Proceedings

Spatiotemporal variation in the local immigration and extinction of species in a community may form and change the spatial heterogeneity (SH) of vegetation but few studies have evaluated the influences of these processes on SH. SH often occurs in grassland grazed by cattle and sheep. Understanding the formation and dynamics of SH is important because SH profoundly affects local and regional ecological processes. We propose a new way to quantify the effect of the local immigration and extinction of species on SH, and try to clarify the influence of the processes on SH


Cattle Slurry Amended With Nitrification Inhibitors: Effects On Nitrous Oxide, Dinitrogen And Methane Emissions, J. P. Carneiro, L. Cardenas, D. Hatch, H. Trindade, J. Hawkins, David Scholefield, D. Chadwick 2023 Escola Superior Agrária de Castelo Branco, Portugal

Cattle Slurry Amended With Nitrification Inhibitors: Effects On Nitrous Oxide, Dinitrogen And Methane Emissions, J. P. Carneiro, L. Cardenas, D. Hatch, H. Trindade, J. Hawkins, David Scholefield, D. Chadwick

International Grassland Congress Proceedings

In recent decades, a very intensive dairy farming system has been developed in northern Portugal. Considering the appreciable amounts of slurry generated and the small farm areas for spreading, this activity involves large annual inputs of N with the risk of undesirable consequences for the environment. Emission of greenhouse gases from agricultural sources, such as N2O (originating from nitrification and denitrification) and CH4, therefore need to be reduced. The aim of this laboratory experiment was to evaluate the effectiveness of two nitrification inhibitors (dicyandiamide (DCD) and 3,4-dimethylpyrazole phosphate (DMPP)) in reducing nitrification and subsequent denitrification after …


Methane Production By Cattle Grazed At Two Stocking Rates On A Semi-Natural Grassland, Cesar S. Pinares-Patiño, Y. Rochette, M. Fabre, J.-P. Jouany, C. Martin 2023 AgResearch, New Zealand

Methane Production By Cattle Grazed At Two Stocking Rates On A Semi-Natural Grassland, Cesar S. Pinares-Patiño, Y. Rochette, M. Fabre, J.-P. Jouany, C. Martin

International Grassland Congress Proceedings

Global warming induced by the human-enhanced concentrations of greenhouse gases (GHG) in the atmosphere is a major environmental concern of our day. Enteric methane (CH4) is the most important GHG associated with grazing livestock. The emissions of methane may be influenced by environmental conditions and grazing management. Stocking rate (SR), the number of animals per unit of land area, remains the simplest management tool in pastoral farming. However, little is known about the influence of SR on CH4 emission. The objective of this study was to compare the CH4 emissions from cattle managed under low and …


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