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2019

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Articles 211 - 240 of 1656

Full-Text Articles in Earth Sciences

Structural And Geochronologic Constraints On The Duration Of The Picuris Orogeny And Demise Of An Orogenic Plateau, Northern Nm, Daniel J. Young Dec 2019

Structural And Geochronologic Constraints On The Duration Of The Picuris Orogeny And Demise Of An Orogenic Plateau, Northern Nm, Daniel J. Young

Earth and Planetary Sciences ETDs

Metasedimentary and igneous basement rocks in northern New Mexico record episodic pulses of tectonism during cratonic growth from 1.8 to 1.38 Ga. Continued challenges involve parsing the deformational features attributable to the Yavapai Orogeny (1.71-1.68 Ga), Mazatzal orogeny (1.66-1.60 Ga), and Picuris orogeny (1.5-1.38 Ga) in this region and understanding how older structures may have been overprinted and reactivated to explain the observed strain. This paper presents regional cross-sections of the 1.7 Ga Vadito, 1.68 to 1.50 Ga Hondo, and 1.5-1.45 Ga Trampas groups of the Picuris Mountains and Rio Mora areas of northern New Mexico combined with new geochronologic …


Integrating Lidar Data And Multi-Temporal Aerial Imagery To Map Wetland Inundation Dynamics Using Google Earth Engine, Qiusheng Wu, Charles B. Lane, Xuecao Li, Kaiguang Zhao, Yuyu Zhou, Nicholas Clinton, Ben Devries, Heather E. Golden, Megan W. Lang Dec 2019

Integrating Lidar Data And Multi-Temporal Aerial Imagery To Map Wetland Inundation Dynamics Using Google Earth Engine, Qiusheng Wu, Charles B. Lane, Xuecao Li, Kaiguang Zhao, Yuyu Zhou, Nicholas Clinton, Ben Devries, Heather E. Golden, Megan W. Lang

United States Environmental Protection Agency: Publications

The Prairie Pothole Region of North America is characterized by millions of depressional wetlands, which provide critical habitats for globally significant populations of migratory waterfowl and other wildlife species. Due to their relatively small size and shallow depth, these wetlands are highly sensitive to climate variability and anthropogenic changes, exhibiting inter- and intra-annual inundation dynamics. Moderate-resolution satellite imagery (e.g., Landsat, Sentinel) alone cannot be used to effectively delineate these small depressional wetlands. By integrating fine spatial resolution Light Detection and Ranging (LiDAR) data and multi-temporal (2009–2017) aerial images, we developed a fully automated approach to delineate wetland inundation extent at …


Resurgence Of An Apex Marine Predator And The Decline In Prey Body Size, Jan Ohlberger, Daniel E. Schindler, Eric J. Ward, Timothy E. Walsworth, Timothy E. Essington Dec 2019

Resurgence Of An Apex Marine Predator And The Decline In Prey Body Size, Jan Ohlberger, Daniel E. Schindler, Eric J. Ward, Timothy E. Walsworth, Timothy E. Essington

Watershed Sciences Faculty Publications

In light of recent recoveries of marine mammal populations worldwide and heightened concern about their impacts on marine food webs and global fisheries, it has become increasingly important to understand the potential impacts of large marine mammal predators on prey populations and their life-history traits. In coastal waters of the northeast Pacific Ocean, marine mammals have increased in abundance over the past 40 to 50 y, including fish-eating killer whales that feed primarily on Chinook salmon. Chinook salmon, a species of high cultural and economic value, have exhibited marked declines in average size and age throughout most of their North …


Landscape Evolution Of The Southern Colorado Plateau Using Low-Temperature Apatite Thermochronology And Detrital Zircon And Sanidine Provenance Studies, Carmen L. Winn Dec 2019

Landscape Evolution Of The Southern Colorado Plateau Using Low-Temperature Apatite Thermochronology And Detrital Zircon And Sanidine Provenance Studies, Carmen L. Winn

Earth and Planetary Sciences ETDs

Chapter 1: Westernmost Grand Canyon

Conflicting hypotheses about the timing of carving of the Grand Canyon involve either a 70 Ma (“old”) or < 6 Ma (“young”) Grand Canyon. This paper evaluates the controversial westernmost segment of the Grand Canyon where the following lines of published evidence firmly favor a “young” Canyon. 1) North-derived Paleocene Hindu Fanglomerate was deposited across the present track of the westernmost Grand Canyon, which therefore was not present at ~55 Ma. 2) The 19 Ma Separation Point basalt is stranded between high relief side canyons feeding the main stem of the Colorado River and was emplaced before these tributaries and the main canyon were incised. 3) Geomorphic constraints indicate that relief generation in tributaries and on plateaus adjacent to the westernmost Grand Canyon took place after 17 Ma. 4) The late Miocene-Pliocene Muddy Creek Formation constraint shows that no river carrying far-traveled materials exited at the mouth of the Grand Canyon until after 6 Ma.

Interpretations of previously-published low-temperature thermochronologic data conflict with these lines of evidence, but are reconciled in this paper via the integration of three methods of analyses on the same sample: apatite (U-Th)/He ages (AHe), 4He/3He thermochronometry (4He/3He), and apatite fission-track ages and lengths (AFT). “HeFTy” software was used to generate time-temperature (t-T) paths that predict all new and published 4He/3He, AH, and AFT data to within assumed …


Resolving Time-Space Histories Of Late Cenozoic Bedrock Incision Along The Upper Colorado River, Usa, Andres Aslan, Karl E. Karlstrom, Eric Kirby, Matthew T. Heizler, Darryl E. Granger, James K. Feathers, Paul R. Hanson, Shannon A. Mahan Dec 2019

Resolving Time-Space Histories Of Late Cenozoic Bedrock Incision Along The Upper Colorado River, Usa, Andres Aslan, Karl E. Karlstrom, Eric Kirby, Matthew T. Heizler, Darryl E. Granger, James K. Feathers, Paul R. Hanson, Shannon A. Mahan

School of Natural Resources: Faculty Publications

The upper Colorado River basin drains the western slope of the Rocky Mountains province of North America and hosts a rich record of fluvial terraces and volcanic deposits that provide an archive of bedrock river incision since the Late Miocene. Here we present new geochronology from fluvial deposits and associated volcanic units using multiple methods (luminescence, cosmogenic-burial, 40Ar/39Ar basalt and detrital sanidine, and U/Pb detrital zircon) to reconstruct a detailed record of bedrock incision in the upper Colorado River over timescales ranging from Miocene to Late Pleistocene. Late Miocene (ca. 11–8 Ma) basalt flows perched 800–1700 m above the Colorado …


Respons Pertumbuhan Tanaman Kelapa Belum Menghasilkan Terhadap Pemberian Air Kelapa Dan Asam Humat, Mira Ariyanti, Santi Rosniawaty, Muhamad Rizky Permana Dec 2019

Respons Pertumbuhan Tanaman Kelapa Belum Menghasilkan Terhadap Pemberian Air Kelapa Dan Asam Humat, Mira Ariyanti, Santi Rosniawaty, Muhamad Rizky Permana

Jurnal Kultivasi

Kelapa kopyor banyak diminati masyarakat karena memiliki sifat yang unik. namun produktivitas kelapa kopyor masih rendah. Peningkatan pertumbuhan kelapa kopyor belum menghasilkan dapat dilakukan dengan aplikasi zat pengatur tumbuh alami (ZPT) seperti air kelapa yang diaplikasikan langsung pada tanaman dan asam humat sebagai bahan organik untuk meningkatkan kualitas tanah agar dapat sesuai bagi pertanaman kelapa kopyor. Penelitian ini bertujuan untuk mengetahui pengaruh kombinasi aplikasi air kelapa dan asam humat terbaik terhadap pertumbuhan tanaman kelapa kopyor belum menghasilkan. Penelitian dilaksanakan di Lahan Taman Buah Mekarsari, Cileungsi, Bogor, Jawa Barat, pada bulan Mei 2018-Oktober 2018. Penelitian ini menggunakan tanah berordo Ultisols. Metode …


Examination Of Maskelynite Through Static Recompression And Dynamic Compression, Justin James Reppart Dec 2019

Examination Of Maskelynite Through Static Recompression And Dynamic Compression, Justin James Reppart

UNLV Theses, Dissertations, Professional Papers, and Capstones

This is an experimental study that aims to clarify the possible formation mechanisms of maskelynite. Maskelynite is a diaplectic glass, that forms during shock compression of feldspar far below the melting point, and without fusion. Maskelynite also paramorphises precursor feldspar grains. Maskelynite is an important probe of shock-pressures at terrestrial impact sites and in many meteorites. Two mechanisms of formation of maskelynite are examined here: 1) maskelynite is result of a pressure-induced amorphization of feldspar compressed beyond its mechanical stability where the formation of thermodynamically stable phases is kinetically inhibited [1, 2]. 2) Feldspar transforms upon dynamic compression into a …


Moisture Dynamics Of A Near-Surface Desert Soil, Yuan Luo Dec 2019

Moisture Dynamics Of A Near-Surface Desert Soil, Yuan Luo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Desert soils cover about one third of the Earth’s land surface. Despite their large extent, however, our understanding of desert soil hydraulic processes and properties is still rather limited. In particularly with respect to the near-surface (top centimeters) of the soil profile, which play a critical role for infiltration, redistribution and evapotranspiration of rainwater, the limiting resource for life in desert environments, but also hosts most of the biologic activity and controls runoff, erosion as well as the emission of dust (Nannipieri et al.,2003; Bradford et al.,1987). Additionally, deserts are ideal locations for electricity generation with solar energy using large-scale …


Utility Of Bench Scale Sand Tank Experiments At Assessing Permeable Reactive Barrier Design, Brandon Meier Dec 2019

Utility Of Bench Scale Sand Tank Experiments At Assessing Permeable Reactive Barrier Design, Brandon Meier

UNLV Theses, Dissertations, Professional Papers, and Capstones

The objective of this work was to evaluate the utility of bench scale sand tank experiments at assessing permeable reactive barrier (PRB) design. Our criteria for meeting this goal was that differences between PRB designs could be identified solely by measuring concentration in outflow from the sand tank models. For our PRB designs (funnel-and-gate, staggered wells, and parallel bars), numerical simulations clearly showed that PRB design had a quantifiable effect on outflow concentration, provided that the solute reacted with the PRB materials. Conversely, use of a conservative (non-reactive) solute did not allow us to discern between PRB design alternatives. Employing …


Urinary Excretion Of Mimosine Derivatives By Cows With And Without Experience In Consumption Of Leucaena Leucocephala, N. E. Ruz-Ruiz, Eduardo G. Briceño-Poot, A. J. Ayala-Burgos, C. F. Aguilar-Pérez, Francisco J. Solorio-Sánchez, Luis Ramírez-Avilés, Juan C. Ku-Vera Dec 2019

Urinary Excretion Of Mimosine Derivatives By Cows With And Without Experience In Consumption Of Leucaena Leucocephala, N. E. Ruz-Ruiz, Eduardo G. Briceño-Poot, A. J. Ayala-Burgos, C. F. Aguilar-Pérez, Francisco J. Solorio-Sánchez, Luis Ramírez-Avilés, Juan C. Ku-Vera

IGC Proceedings (1977-2023)

Leucaena leucocephala is a leguminous tree widely distributed in the tropical regions of the world. In Mexico, it has been incorporated into silvopastoral systems and is highly regarded, owing to its high content of crude protein. Nonetheless, L. leucocephala contains secondary metab-olites, such as mimosine, a non-protein free amino acid, which may induce toxic effects in unadapted ruminants that consume the forage (Hammond 1995). Although Synergistes jonesii, an anaerobic bacterium, has the ability to degrade 3,4-DHP and 2,3-DHP to non-toxic compounds (Allison et al. 1992), in Mexico its presence has not yet been confirmed. Recent work has suggested …


Urinary Excretion Of Mimosine Metabolites By Hair Sheep Fed Foliage Of Leucaena Leucocephala, L. M. Contreras-Hernández, N. E. Ruz-Ruiz, Eduardo G. Briceño-Poot, Luis Ramírez-Avilés, A. J. Ayala-Burgos, C. F. Pérez-Aguilar, Francisco J. Solorio-Sánchez, Juan C. Ku-Vera Dec 2019

Urinary Excretion Of Mimosine Metabolites By Hair Sheep Fed Foliage Of Leucaena Leucocephala, L. M. Contreras-Hernández, N. E. Ruz-Ruiz, Eduardo G. Briceño-Poot, Luis Ramírez-Avilés, A. J. Ayala-Burgos, C. F. Pérez-Aguilar, Francisco J. Solorio-Sánchez, Juan C. Ku-Vera

IGC Proceedings (1977-2023)

Leucaena leucocephala is an adapted legume widely distributed in the tropical regions of Mexico. The high crude protein content of leucaena leaves renders it appropriate for ruminant feeding under commercial conditions. However, the foliage contains the non-protein amino acid mimosine, which, if consumed in high amounts, may induce toxicity in animals which have not previously consumed the legume or without microorganisms capable of degrading mimosine and its derivatives 2,3-DHP (dihydroxypyridine) and 3,4-DHP (Hammond 1995, Palmer et al. 2010, Dalzell et al. 2012). Barros-Rodríguez et al. (2012) found that dry matter intake and weight gain were reduced when …


Animal Production From New Panicum Maximum Genotypes In The Amazon Biome, Brazil, Carlos M. S. De Andrade, Luis H. E. Farinatti, Hemython L. B. Do Nascimento, Andressa De Q. Abreu, Liana Jank, Giselle M. L. De Assis Dec 2019

Animal Production From New Panicum Maximum Genotypes In The Amazon Biome, Brazil, Carlos M. S. De Andrade, Luis H. E. Farinatti, Hemython L. B. Do Nascimento, Andressa De Q. Abreu, Liana Jank, Giselle M. L. De Assis

IGC Proceedings (1977-2023)

The Panicum maximum breeding program coordinated by the Brazilian Agricultural Research Corporation - Embrapa has been evaluating and selecting genotypes under different soil and climatic conditions, with the objective to release new cultivars adapted to the diverse regions of Brazil. For the Amazon biome, small-plot experiments carried out in Acre between 2003 and 2005 allowed the selection of some promising genotypes (Valentim and Andrade 2005; Valentim et al. 2006; Andrade and Valentim 2009), with higher potential for forage growth than cultivars on the market. The objective of this work was to compare 2 new P. maximum genotypes with cv. …


Tropical Grass Growth Functions Modeling By Using Nonlinear Mixed Models, A. Hernández Garay, H. Vaquera Huerta, M. Calzada Marín, E. Ortega Jiménez, J. F. Enríquez Quiroz Dec 2019

Tropical Grass Growth Functions Modeling By Using Nonlinear Mixed Models, A. Hernández Garay, H. Vaquera Huerta, M. Calzada Marín, E. Ortega Jiménez, J. F. Enríquez Quiroz

IGC Proceedings (1977-2023)

Nonlinear Growth curves are used for modeling plant physiological variables. These models are preferable because the polynomial coefficients of the equations have a biological significance. The response variables of the curves occurs commonly with repeated measurements over time and measurements are on different environments. The traditional statistical analysis does not include a repeated measures approach, which can lead to improper estimation of the error terms. It is important to study the growth of tropical grass (Da Silva and Carvalho 2005).


Herbage Accumulation, Nutritive Value And Persistence Of Mulato Ii In Florida, Joao M. B. Vendramini, Lynn E. Sollenberger, Graham C. Lamb, Maria L. Silveira Dec 2019

Herbage Accumulation, Nutritive Value And Persistence Of Mulato Ii In Florida, Joao M. B. Vendramini, Lynn E. Sollenberger, Graham C. Lamb, Maria L. Silveira

IGC Proceedings (1977-2023)

Grasses in the Brachiaria genus are the most widely grown forages in tropical America, occupying over 80 Mha (Boddey et al. 2004). Mulato II is apomictic and a vigorous, semi-erect cultivar resulting from 3 generations of crosses including original crosses between ruzigrass and signal-grass (cv. Basilisk, apomictic tetrapliod). According to Peters et al. (2003), Mulato produced 25% more herbage mass than palisadegrass (Brachiaria brizantha) and koroni-viagrass (Brachiaria humidicola) under similar management practices. Although Mulato II shows promise as a forage in tropical regions, herbage accumulation and persistence in subtropical areas is unknown. This publication …


Agronomic And Nutritional Evaluation Of Intraspecific Crosses In Brachiaria Decumbens, Simony A. Mendonça, Sanzio C. L. Barrios, Ulisses J. De Figueiredo, Geovani F. Alves, Cacilda B. Valle Dec 2019

Agronomic And Nutritional Evaluation Of Intraspecific Crosses In Brachiaria Decumbens, Simony A. Mendonça, Sanzio C. L. Barrios, Ulisses J. De Figueiredo, Geovani F. Alves, Cacilda B. Valle

IGC Proceedings (1977-2023)

Brachiaria decumbens cv. Basilisk is the single most important forage grass used for pastures in the tropics. This cultivar has exceptional adaptation to acid soils, vigorous growth, ease of establishment, and good forage value throughout the year, but these favourable characteristics are counteracted by its susceptibility to insect pests such as spittlebug. Breeding to produce improved cultivars within this species was impossible until 2009 due to the lack of compatible sexual ecotypes. With the success of somatic chromosome duplication of sexually reproducing diploid plants of B. decumbens (Simioni and Valle 2009), intraspecific crosses with natural apomictic tetraploid accessions were finally …


Reciprocal Recurrent Selection In The Breeding Of Brachiaria Decumbens, Sanzio C. L. Barrios, Cacilda B. Valle, Geovani F. Alves, Rosangela M. Simeão, Liana Jank Dec 2019

Reciprocal Recurrent Selection In The Breeding Of Brachiaria Decumbens, Sanzio C. L. Barrios, Cacilda B. Valle, Geovani F. Alves, Rosangela M. Simeão, Liana Jank

IGC Proceedings (1977-2023)

Pastures of Brachiaria decumbens cv. Basilisk radically changed the scenario of livestock production in central Brazil in the early 1970s and in fact, promoted the development of this vast region. However, despite the reasonable biomass yields and nutritional value when grown on these tropical acid soils, its susceptibility to grassland spittlebugs has limited its use. The breeding of B. decumbens in Brazil has been restricted to interspecific crosses using cv. Basilisk as a pollen donor due to the lack of compatible sexual ecotypes within this species. Recently, the successful chromosome duplication of a sexually reproducing diploid accession produced 3 successful …


ProgardesTm: A Legume For Tropical/Subtropical Semi-Arid Clay Soils, Christopher Gardiner, Nick Kempe, Iain Hannah, Jim Mcdonald Dec 2019

ProgardesTm: A Legume For Tropical/Subtropical Semi-Arid Clay Soils, Christopher Gardiner, Nick Kempe, Iain Hannah, Jim Mcdonald

IGC Proceedings (1977-2023)

The range of available sown pasture legumes for the vast heavy clay soil regions of northern Australia has long been regarded as being deficient (Burt 1993; Jones and Clem 1997; Pengelly and Conway 2000). Indeed immense areas of northern Australia’s semi-arid clay soil regions have no sown pasture legume with proven adaptation and persistence through the long annual dry seasons (Gardiner and Swan 2008). The genus Desmanthus is a Mimosaceae legume containing some 24 species which are native to the Americas and range from being herbaceous to suffruticose in habit (Luckow 1993). Desmanthus is one of the very few legumes …


Potential Of Panicum Maximum As A Source Of Energy, Liana Jank, Edson A. De Lima, Rosangela M. Simeão, Ronimar C. Andrade Dec 2019

Potential Of Panicum Maximum As A Source Of Energy, Liana Jank, Edson A. De Lima, Rosangela M. Simeão, Ronimar C. Andrade

IGC Proceedings (1977-2023)

The use of plant biomass as a source of energy presents many advantages, mainly that it is a renewable, clean source of energy. Many tropical grasses have excellent po-tential as energy crops. The main one in Brazil is Pennisetum purpureum (elephant grass) owing to its very high yields. However, it is vegetatively propagated, thus more difficult to establish than seed propagated species. The use of Panicum maximum (guinea grass) is a possible alternative for use as a source of energy, due to its high yields as well as seed propagation. The objective of this research was to evaluate the potential …


Quality Seed Production Of Range Grasses--A Major Constraint In Revitalising Tropical Pastures, D. R. Malaviya, D. Vijay, Chandan Kumar Gupta, Ajoy K. Roy, P. Kaushal Dec 2019

Quality Seed Production Of Range Grasses--A Major Constraint In Revitalising Tropical Pastures, D. R. Malaviya, D. Vijay, Chandan Kumar Gupta, Ajoy K. Roy, P. Kaushal

IGC Proceedings (1977-2023)

Only 4% of India’s geographical area of 326.82 M ha is under pastures. Socioeconomic and ecological consequ-ences of land degradation are affecting 85 M ha of rangelands/grasslands. To provide sufficient milk for the ever-growing population, current milk production of 128 M t must increase to 160 M t by 2020. To make this possible, an additional 825 M t of green fodder is required. Increasing the area producing green fodder is difficult because of severe competition from food crops. Revitalising the denuded grasslands is the most plausible means for improving the availability of green fodder. This needs mission mode programs …


Status Of Animal Feed Resources In Rwanda, M. Mutimura, A. B. Lussa, J. Mutabazi, C. B. Myambi, R. A. Cyamweshi, C. Ebong Dec 2019

Status Of Animal Feed Resources In Rwanda, M. Mutimura, A. B. Lussa, J. Mutabazi, C. B. Myambi, R. A. Cyamweshi, C. Ebong

IGC Proceedings (1977-2023)

Animal feed resources remain a major constraint for livestock development in tropical Africa. In Rwanda, grazing lands are shrinking sharply because crop cultivation is progressively encroaching on grazing areas with increasing human pressure (Mutimura and Everson 2011). Therefore, over 60% of households cultivating less than 0.7 ha, and owning livestock, practise zero-grazing, where farmers cut-and-carry forage and crop residues to feed animals that are kept exclusively under sheds (MINAGRI 2009). In general, the main feed for dairy cattle under a zero-grazing system is Napier grass (Pennisetum purpureum). For more than a decade, efforts to improve the feed resource …


Effect Of Cutting Interval On Yield And Quality Of Two Panicum Maximum Cultivars In Thailand, Michael D. Hare, Supaphan Phengphet, Theerachai Songsiri, Naddakorn Sutin, Eduardo Stern Dec 2019

Effect Of Cutting Interval On Yield And Quality Of Two Panicum Maximum Cultivars In Thailand, Michael D. Hare, Supaphan Phengphet, Theerachai Songsiri, Naddakorn Sutin, Eduardo Stern

IGC Proceedings (1977-2023)

Tanzania guinea grass [Panicum maximum cv. Tanzania (cv. Purple in Thailand)] has been grown in Thailand for over 20 years and has proven to be a high quality forage (Phaikaew et al. 2007). Mombasa guinea grass (Panicum maximum cv. Mombasa) was introduced to Thailand in 2007 and commercial seed production commenced in 2008 because of a demand for seed in central and South America (Hare et al. 2013). It is a larger and taller cultivar than Tanzania. A series of studies have been undertaken at Ubon Ratchathani University, Thailand, to study the agronomic differences between these …


Effect Of Cutting Interval On Yield And Quality Of Three Brachiaria Hybrids In Thailand, Michael D. Hare, Supaphan Phengphet, Theerachai Songsiri, Naddakorn Sutin, Eduardo Stern Dec 2019

Effect Of Cutting Interval On Yield And Quality Of Three Brachiaria Hybrids In Thailand, Michael D. Hare, Supaphan Phengphet, Theerachai Songsiri, Naddakorn Sutin, Eduardo Stern

IGC Proceedings (1977-2023)

In field trials in Thailand, Brachiaria hybrid cv. Mulato II produced significantly more green leaf, particularly during the dry season, than other brachiaria grasses (Hare et al. 2009). Cultivar Cayman produced more dry matter (DM) than Mulato II in one out of 3 wet seasons, and line BRO2/1794 produced similar DM yields to Mulato II (Pi-zarro et al. 2013).

The objective of this field study was to determine the effects of varying cutting intervals on growth and forage quality of hybrid brachiaria grasses in Thailand on infertile soils.


Brachiaria Hybrids: Potential, Forage Use And Seed Yield, Esteban A. Pizarro, Michael D. Hare, Mpenzi Mutimura, Changjun Bai Dec 2019

Brachiaria Hybrids: Potential, Forage Use And Seed Yield, Esteban A. Pizarro, Michael D. Hare, Mpenzi Mutimura, Changjun Bai

IGC Proceedings (1977-2023)

A brachiaria breeding program initiated in 1988 at CIAT (Centro Internacional de Agricultura Tropical) combined desirable attributes found in accessions of Brachiaria brizantha and B. decumbens. Three apomictic hybrids have been released (cvs. Mulato, Mulato II and Cayman). Mulato showed agronomic potential but seed yields were low. Trials in Central America demonstrated the superiority of Mulato II, a vigorous grass with very deep and branched roots, giving it excellent drought resistance in the Brazilian Cerrado and Mexico. Mulato II has excellent nutritional value. Following trials in Mexico and Thailand, evaluating 155 new hybrids for 7 years, cv. Cayman was …


Molecular Genetic Variability, Population Structure And Mating System In Tropical Forages, Melissa Garcia, Bianca B. Z. Vigna, Adna C. B. Sousa, Letícia Jungmann, Fernanda W. Cidade, Guilherme Toledo-Silva, Patricia M. Francisco, Lucimara Chiari, Marcelo A. Carvalho, Claudio T. Karia, Fabio G. Faleiro, Rodolfo Godoy, M. Dall’Agnol, Sueli S. Pagliarini, Francisco H. D. Souza, Tatiana T. Souza-Chies, Liana Jank, Rosangela M. S. Resende, Cacilda B. Valle, Maria I. Zucchi, Anete P. Souza Dec 2019

Molecular Genetic Variability, Population Structure And Mating System In Tropical Forages, Melissa Garcia, Bianca B. Z. Vigna, Adna C. B. Sousa, Letícia Jungmann, Fernanda W. Cidade, Guilherme Toledo-Silva, Patricia M. Francisco, Lucimara Chiari, Marcelo A. Carvalho, Claudio T. Karia, Fabio G. Faleiro, Rodolfo Godoy, M. Dall’Agnol, Sueli S. Pagliarini, Francisco H. D. Souza, Tatiana T. Souza-Chies, Liana Jank, Rosangela M. S. Resende, Cacilda B. Valle, Maria I. Zucchi, Anete P. Souza

IGC Proceedings (1977-2023)

Microsatellite (SSR) markers were developed for the following tropical forage species, using accessions available from the plant genetic resources (PGR) collections held by EMBRAPA (Brazilian Agricultural Research Corporation): Brachiaria brizantha, B. humidicola, Panicum maximum, Paspalum spp., Stylosanthes capitata, S. guianensis, S. macrocephala, Calopogonium mucunoides and Centrosema spp. The markers were used to analyse population structure and genetic diversity, evolution and origin of the genetic variability in the centre of origin, mating systems and genetic resources in EMBRAPA’s germplasm bank. The results shed light on the amount of genetic variation within and between populations, revealed …


Leucaena Toxicity: A New Perspective On The Most Widely Used Forage Tree Legume, Michael J. Halliday, Jagadish Padmanabha, Chris S. Mcsweeney, Graham L. Kerven, H. Max Shelton Dec 2019

Leucaena Toxicity: A New Perspective On The Most Widely Used Forage Tree Legume, Michael J. Halliday, Jagadish Padmanabha, Chris S. Mcsweeney, Graham L. Kerven, H. Max Shelton

IGC Proceedings (1977-2023)

The tree legume Leucaena leucocephala (leucaena) is a high quality ruminant feed, vitally important for livestock production in the tropics despite the presence of mimosine in the leaves. This toxic non-protein amino acid has the potential to limit productivity and adversely affect the health of animals. The discovery and subsequent distribution in Australia of the ruminal bacterium Synergistes jonesii as an oral inoculum was shown in the 1980s to overcome these toxic effects. However, recent surveys of the status of toxicity worldwide; improved understanding of the chemistry and mode of action of the toxins; new techniques for molecular sequencing; and …


Using Archaeological Remote Sensing To Evaluate Land Use And Constructed Space In Chaco Canyon, Jennie Odessa Sturm Dec 2019

Using Archaeological Remote Sensing To Evaluate Land Use And Constructed Space In Chaco Canyon, Jennie Odessa Sturm

Anthropology ETDs

Archaeological remote sensing includes a suite of non-invasive methods that can be used to study elements of the archaeological record that may not be achievable otherwise. Using primarily geophysical remote sensing, and especially ground-penetrating radar (GPR), three studies involving questions of “use” were conducted in Chaco Canyon, New Mexico. The first used GPR to study the built interior features of a single room in Pueblo Bonito to evaluate use and function of that room. Three categories of features were identified in the GPR data and confirmed with subsequent excavation. The second study used GPR to re-evaluate an enigmatic land use …


Basal Travertine Of The Bouse Formation: Geochemistry, Diagenesis And Implications For The Integration Of The Colorado River, Christina Ferguson Dec 2019

Basal Travertine Of The Bouse Formation: Geochemistry, Diagenesis And Implications For The Integration Of The Colorado River, Christina Ferguson

Earth and Planetary Sciences ETDs

The Pliocene Bouse Formation is discontinuously exposed in the lower Colorado River region and is a record of the first arrival of the Colorado River to the Gulf of California 5 million years ago. It consists broadly of a lower carbonate member (travertine, marl, and bioclastic units) and an upper siliciclastic member (claystone, mudstone, and Colorado River sands). This paper focuses on the basal travertine (synonymous with “tufa”) unit of the lower carbonate member. Because of its basal position and its chemical encrustation of pre-Bouse topography, the travertine can offer insight into the earliest depositional settings and may be a …


Pengaruh Bahan Organik Berbasis Gulma Paitan Dan Pupuk Npk Terhadap Sifat Kimia Tanah, Pertumbuhan, Dan Hasil Tomat Pada Ultisols, Intan Abas Nur Khairunnisa, Anung Slamet Dwi, Sapto Nugroho Hadi Dec 2019

Pengaruh Bahan Organik Berbasis Gulma Paitan Dan Pupuk Npk Terhadap Sifat Kimia Tanah, Pertumbuhan, Dan Hasil Tomat Pada Ultisols, Intan Abas Nur Khairunnisa, Anung Slamet Dwi, Sapto Nugroho Hadi

Jurnal Kultivasi

Penelitian ini bertujuan untuk mengetahui pengaruh bahan organik gulma paitan dan pupuk NPK terhadap sifat kimia tanah (C organik, N, dan P total), serta pertumbuhan dan hasil tomat pada Ultisols. Penelitian dilaksanakan di screen house Fakultas Pertanian, Universitas Jenderal Soedirman, Purwokerto, pada bulan Juni sampai September 2018. Penelitian ini menggunakan rancangan perlakuan faktorial 3x3. Faktor pertama adalah bahan organik tumbuhan paitan, terdiri atas 3 taraf, yaitu 0, 125, dan 250 g/tanaman. Faktor kedua adalah dosis NPK, terdiri atas 3 taraf, yaitu 0; 3,61; dan 5,42 g/tanaman. Seluruh kombinasi perlakuan dialokasikan ke dalam unit percobaan dengan menggunakan Rancangan Acak Kelompok yang …


A Climatology Of Snowpack In The Southern Rocky Mountains And Snow To Liquid Ratio Forecasting Techniques Using Model Generated Soundings From The Rapid Refresh Model, Carson Jones Dec 2019

A Climatology Of Snowpack In The Southern Rocky Mountains And Snow To Liquid Ratio Forecasting Techniques Using Model Generated Soundings From The Rapid Refresh Model, Carson Jones

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

Mountainous snowpack represents up to 70% of the total water resources for areas in the western United States. Temperature and precipitation control the accumulation and ablation of the snowpack throughout the cold season, both of which are subject to a changing climate. This study will use a network of snow telemetry (SNOTEL) stations to investigate changes in the snowpack season, snow water equivalent (SWE), and temperature in the southern Rocky Mountain region. Additionally, this study will use model generated soundings from the Rapid Refresh (RAP) model to establish relationships between the depth and cloud proportion of ice crystal growth layers, …


Bringing Statistical Learning Machines Together For Hydro-Climatological Predictions - Case Study For Sacramento San Joaquin River Basin, California, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad, Kenneth W. Lamb, Venkat Lakshmi Dec 2019

Bringing Statistical Learning Machines Together For Hydro-Climatological Predictions - Case Study For Sacramento San Joaquin River Basin, California, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad, Kenneth W. Lamb, Venkat Lakshmi

Civil and Environmental Engineering and Construction Faculty Research

Study region: Sacramento San Joaquin River Basin, California Study focus: The study forecasts the streamflow at a regional scale within SSJ river basin with largescale climate variables. The proposed approach eliminates the bias resulting from predefined indices at regional scale. The study was performed for eight unimpaired streamflow stations from 1962–2016. First, the Singular Valued Decomposition (SVD) teleconnections of the streamflow corresponding to 500 mbar geopotential height, sea surface temperature, 500 mbar specific humidity (SHUM500), and 500 mbar U-wind (U500) were obtained. Second, the skillful SVD teleconnections were screened non-parametrically. Finally, the screened teleconnections were used as the streamflow predictors …