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2003

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Articles 151 - 180 of 368

Full-Text Articles in Earth Sciences

The Duration-Amplitude Distribution Of Volcanic Tremor, John P. Benoit, Stephen R. Mcnutt, Vilma Barboza Mar 2003

The Duration-Amplitude Distribution Of Volcanic Tremor, John P. Benoit, Stephen R. Mcnutt, Vilma Barboza

School of Geosciences Faculty and Staff Publications

The duration-amplitude distribution of volcanic tremor was examined in eight volcanoes and one geothermal area. An exponential model, implying a scale-bound source process, is found to be a better fit to the data than a power law (scale invariant) model. The exponential model well describes tremor associated with magmatic and phreatic eruptions, shallow and deep source regions, and geothermal sources. We tested the exponential model described by: , where d is the duration of tremor greater than or equal to a particular amplitude DR, dt is the total duration of tremor, and the inverse of λ is …


Wayne E. Sabbe Arkansas Soil Fertility Studies 2002, Nathan A. Slaton Mar 2003

Wayne E. Sabbe Arkansas Soil Fertility Studies 2002, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts also be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies contained within will allow producers to compare their practices with the university’s research efforts. Additionally, soil test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.


Alfalfa Disease Management, Paul Vincelli Feb 2003

Alfalfa Disease Management, Paul Vincelli

Kentucky Alfalfa and Stored Forage Conference

Alfalfa can be a vigorous and productive forage crop for Kentucky farmers. Like all farm crops, however, alfalfa is subject to infectious diseases that can limit forage production. Managing these diseases is an important part of economical alfalfa production.


Weed Management In Alfalfa, Jonathan D. Green Feb 2003

Weed Management In Alfalfa, Jonathan D. Green

Kentucky Alfalfa and Stored Forage Conference

The importance of weed control in forage production should not be overlooked, especially when you consider the high investment associated with alfalfa and other legume forages. Weed management strategies in forage legumes should first focus on cultural practices and then on chemical weed control options. Vigorous, densely growing forage legume stands tend to have fewer weed problems. Thus, cultural and management practices that promote a highly competitive forage stand help prevent many weed problems. These practices include: 1) liming and fertilizing fields based on soil test recommendations; 2) seeding well-adapted, vigorous, and long-lived varieties; 3) buying weed-free seed; 4) cutting …


Producing Quality Alfalfa Hay, Jimmy C. Henning, Garry D. Lacefield Feb 2003

Producing Quality Alfalfa Hay, Jimmy C. Henning, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

Hay is one of the most versatile of stored forages in that (1) it can be kept for long periods of time with little loss of nutrients if protected from weather; (2) a large number of crops can be successfully used for hay production; (3) it can be produced and fed in small or large amounts; (4) it can be harvested, stored and fed by hand or the production and feeding can be completely mechanized; and (5) hay can supply most nutrients needed by many classes of livestock. Hay is, therefore, the most commonly used stored feed on most farms.


Forage Testing & Marketing Program, Allen Johnson Feb 2003

Forage Testing & Marketing Program, Allen Johnson

Kentucky Alfalfa and Stored Forage Conference

Two thousand and three marks the 141th year for the Kentucky Department of Agriculture for testing forages. We continue to strive to offer a quality service to producers at the very least cost possible. After all these years we continue to charge only $10.00 per lot or cutting and have expanded our services to try to meet the needs of our forage and livestock producers. In January 2002, we introduced the testing of haylages and have expanded this to cover most of the haylage crops harvested in Kentucky. In cooperation with The University of Kentucky Extension Service, the department …


Buying And Selling Alfalfa Hay, Garry D. Lacefield, Jimmy C. Henning Feb 2003

Buying And Selling Alfalfa Hay, Garry D. Lacefield, Jimmy C. Henning

Kentucky Alfalfa and Stored Forage Conference

Alfalfa hay is an important agricultural product. Although often fed on the farms where it is produced, much alfalfa hay is also sold as a cash crop. It often constitutes a major source of income for those who sell it, or a major expense for those who buy it. Such transactions involve billions of dollars nationwide each year.


Alfalfa Haylage And Silage, Michael Collins Feb 2003

Alfalfa Haylage And Silage, Michael Collins

Kentucky Alfalfa and Stored Forage Conference

Even with extended grazing systems, typical winter weather conditions in Kentucky necessitate the production of some stored forage for livestock during winter. Hay has traditionally been the way of storing this forage. However, when rain occurs during haymaking operations, the losses can be severe both in yield and in forage quality. Harvest losses are greatest for very dry forage and are low for very wet material like direct cut silage. Silage offers an opportunity to avoid most of the rain damage during harvest because the crop only needs to be left out overnight in most cases to be ready to …


Alfalfa And Mrls: What We Know After One Year Of Testing, Jimmy C. Henning, Wayne Long Feb 2003

Alfalfa And Mrls: What We Know After One Year Of Testing, Jimmy C. Henning, Wayne Long

Kentucky Alfalfa and Stored Forage Conference

The onset of mare reproductive loss syndrome in April 2001 in Kentucky lead to much speculation about its cause. Some of these initial 'suspects' included the ergot alkaloids of tall fescue, potential cyanide content of white clover, wide Calcium/Potassium ratios in pasture, fungal mycotoxins and the presence of certain poisonous plants. Certain consultants also indicated that no one should purchase or feed any Kentucky hay in 2001. However, these statements were not based on any hard information, just one person's opinion. But great damage was done to the confidence in Kentucky grown hay.


Alfalfa, The Queen Of Forage Crops — Reflections After Sixty Years Experience With The Crop, Warren C. Thompson Feb 2003

Alfalfa, The Queen Of Forage Crops — Reflections After Sixty Years Experience With The Crop, Warren C. Thompson

Kentucky Alfalfa and Stored Forage Conference

Yes, it is true I have been involved with alfalfa for 60 years and then some. Fact is I was fortunate enough to pick the World's best forage on which to base much of my career about the same time I fell in love with and married the best lady I ever knew. Betty has stuck with me through these crazy wonderful years. She was largely responsible for matters at home and raising the family. She managed our family and home while I was on the move trying to encourage maybe even coerce farmers in Kentucky and then over the …


Alfalfa For Summer Grazing, Jason Sandefur Feb 2003

Alfalfa For Summer Grazing, Jason Sandefur

Kentucky Alfalfa and Stored Forage Conference

Jason manages the Berle Clay Farm in Paris, Kentucky. The farm has been in the Clay family since the 1770's. The Homestead was built in 1778.

The farming operation consist of approximately 680 acres of orchardgrass-clover, 300 acres of orchardgrass-alfalfa, 210 acres of tall fescue-clover, 100 acres of crops, 13 acres of tobacco and 70 acres in roads, buildings, etc.


Advances In Developing Better Alfalfa Varieties, Jim Moutray Feb 2003

Advances In Developing Better Alfalfa Varieties, Jim Moutray

Kentucky Alfalfa and Stored Forage Conference

Alfalfa breeders continue to actively pursue the development of varieties that will bring more benefits to farmers. Yield and better persistence are our highest priorities. Other traits under selection can make alfalfa easier and cheaper to grow, better and safer for livestock and more attractive to livestock.

The goal of this paper is to update you on the types of alfalfa research going on in the U.S., time tables on when you may expect to see these new developments and how they may help you in your operation.


Alfalfa Hay Quality: Terms And Definitions, Garry D. Lacefield Feb 2003

Alfalfa Hay Quality: Terms And Definitions, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

At the 22nd Kentucky Alfalfa Conference we discussed the relationship among Alfalfa - Yield-Quality-Persistence. In our presentation, we indicated that all three components must be considered for best management of alfalfa stands. Over the past week, I have looked through the past twenty-two years of Alfalfa Conference Proceedings. It's interesting, but not surprising that we have focused far more attention on yield than on quality and/or persistence.

Alfalfa yield (quantity) and quality are both important; however, it is easier for producers to recognize problems associated with quantity than quality because quantity can be easily assessed visually. Thus, forage quantity …


Foreword [2003], Garry D. Lacefield Feb 2003

Foreword [2003], Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

This is the front matter of the proceedings.


Vegetation Establishment For Erosion Control Under Simulated Rainfall, Brent G. Hallock, Misty Scharff, Steve Rein, Kaila Dettman Feb 2003

Vegetation Establishment For Erosion Control Under Simulated Rainfall, Brent G. Hallock, Misty Scharff, Steve Rein, Kaila Dettman

Earth and Soil Sciences

The California Department of Transportation (Caltrans) manages rights of ways that transect 41 m H (101m ac) and span over 3000 m (9000 ft) in elevation from seashore to sup alpine. There are approximately 4,900 native and 1,000 naturalized alien plant species in California. Only a few hundred are reliably useful in erosion and sediment control. Specifying native and naturalized vegetation mixes for use in hydroseeding or plug planting in conjunction with mechanical erosion control methods can have varying result for minimizing accelerated soil erosion. To investigate these factors, Cal Poly, San Luis Obispo, in conjunction with Caltrans and CSU, …


The Design And Construction Of A Rainfall Simulator, Jacqueline Blanquies, Misty Scharff, Brent Hallock Feb 2003

The Design And Construction Of A Rainfall Simulator, Jacqueline Blanquies, Misty Scharff, Brent Hallock

Earth and Soil Sciences

A reliable, accurate and portable rainfall simulator was needed for vegetative and erosion control research at California Polytechnic State University, San Luis Obispo (Cal Poly) for California Department of Transportation (Caltrans) and California State University Sacramento. This simulator was designed to be easily set up and maintained as well as able to create a variety of rainfall regimes. The nozzle performance tests and lateral spacing tests were performed at Cal Poly’s Erosion Research Facility. This simulator was designed and constructed based upon the principles of the Norton Ladder Type Rainfall Simulator. This simulator is the standard for research involving simulated …


Crop Updates - 2003 Lupins, Mark Sweetingham, Bevan J. Buirchell, Geoff Thomas, Amelia Mclarty, Harmohinder Dhammu, Martin Harries, Wayne Parker, Terry Piper, David Nicholson, Jairo Palta, Neil C. Turner, Bob French, Kedar Adhikari, Katia Stefanova, Françoise Berlandier, Glen Riethmuller, Paul Blackwell, Geoff Fosbery, Bill Crabtree, Tracy Gilham, Laurie Wahlsten, Pierre Fievez, Mike Collins, John Holmes, Dirranie Kirby, Ken Adcock, Roger Jones, Rohan Prince, Stuart Johnson, Ramon Hall, Madeleine Ball, Sofia Sipas, David Petterson Feb 2003

Crop Updates - 2003 Lupins, Mark Sweetingham, Bevan J. Buirchell, Geoff Thomas, Amelia Mclarty, Harmohinder Dhammu, Martin Harries, Wayne Parker, Terry Piper, David Nicholson, Jairo Palta, Neil C. Turner, Bob French, Kedar Adhikari, Katia Stefanova, Françoise Berlandier, Glen Riethmuller, Paul Blackwell, Geoff Fosbery, Bill Crabtree, Tracy Gilham, Laurie Wahlsten, Pierre Fievez, Mike Collins, John Holmes, Dirranie Kirby, Ken Adcock, Roger Jones, Rohan Prince, Stuart Johnson, Ramon Hall, Madeleine Ball, Sofia Sipas, David Petterson

Crop Updates

This session covers twenty one papers from different authors

LUPIN ISSUES AND R & D DIRECTIONS

  1. Mark Sweetingham, Department of Agriculture

    ACKNOWLEDGEMENTS

    VARIETIES AND BREEDING

  2. New lupin line for release – WALAN2141, Bevan J, Buirchell, Mark Sweetingham, Geoff Thomas, Amelia McLarty, Harmohinder Dhammu and CVT and Lupin Breeding teams, Department of Agriculture

  3. Lupin variety trial, Martin Harries and Wayne Parker, Department of Agriculture

  4. Herbicide tolerance of new lupins, Harmohinder S. Dhammu, Terry Piper and David Nicholson, Department of Agriculture

    YELLOW AND ALBUS LUPINS

  5. Selection for high lupin yield under terminal drought, Jairo A. Palta1&2, Neil …


Energy‐Constrained Open‐System Magmatic Processes Iv: Geochemical, Thermal And Mass Consequences Of Energy‐Constrained Recharge, Assimilation And Fractional Crystallization (Ec‐Rafc), Wendy A. Bohrson, Frank J. Spera Feb 2003

Energy‐Constrained Open‐System Magmatic Processes Iv: Geochemical, Thermal And Mass Consequences Of Energy‐Constrained Recharge, Assimilation And Fractional Crystallization (Ec‐Rafc), Wendy A. Bohrson, Frank J. Spera

All Faculty Scholarship for the College of the Sciences

A wealth of geochemical and petrological data provide evidence that the processes of fractional crystallization, assimilation, and magma recharge (replenishment) dominate the chemical signatures of many terrestrial igneous rocks. Previous work [Spera and Bohrson, 2001; Bohrson and Spera, 2001] has established the importance of integrating energy, species and mass conservation into simulations of complex magma chamber processes. An extended version of the energy‐constrained formulation, Energy‐Constrained Recharge, Assimilation, Fractional Crystallization (EC‐RAFC), tracks mass and compositional variations of melt, cumulates, and enclaves in a magma body undergoing simultaneous recharge, assimilation, and fractional crystallization [Spera and Bohrson, 2002]. …


High Water Use Plant Options For The Fitzgerald River Catchment : A Case Study, P L. Hill, Nadene Schiller Feb 2003

High Water Use Plant Options For The Fitzgerald River Catchment : A Case Study, P L. Hill, Nadene Schiller

Resource management technical reports

This report summarises the outcomes of a project initiated to examine the potential to integrate high water use plant options into existing farm systems to combat rising watertables and reduce salinity and waterlogging. Planting options investigated include commercial trees, perennials, fodder shrubs, annual crops and native grasses. The research uses a new GIS based methodology for undertaking catchment scale land capability analyses.


Geographic Information System Methodologies To Evaluate Relationships Between Land Use And Groundwater Quality In South Central Kentucky, Rhonda Pfaff Feb 2003

Geographic Information System Methodologies To Evaluate Relationships Between Land Use And Groundwater Quality In South Central Kentucky, Rhonda Pfaff

Masters Theses & Specialist Projects

The development of Geographic Information System (GIS) technology has provided techniques for a holistic approach to the study of karst groundwater contamination. While karst groundwaters supply water to a large percentage of the earth's population, its complex environments often have lacked the scientific examination and conservation measures typical of non-karst regions. In this study, GIS methodologies were explored to examine the relationships between land-use and water quality in karst watersheds. Eight watersheds throughout southern and western Kentucky were examined. The study areas included the Mammoth Cave Karst Aquifer, which is the watershed that drains the Mammoth Cave System, and seven …


Effects Of Holocene Climate Change On Mercury Deposition In Elk Lake, Minnesota: The Importance Of Eolian Transport In The Mercury Cycle, W.F. Cannon, Walter E. Dean, John H. Bullock Jr. Feb 2003

Effects Of Holocene Climate Change On Mercury Deposition In Elk Lake, Minnesota: The Importance Of Eolian Transport In The Mercury Cycle, W.F. Cannon, Walter E. Dean, John H. Bullock Jr.

United States Geological Survey: Staff Publications

Sediments in Elk Lake, Minnesota, consist of 10,400 varve layers that provide a precise chronology for Holocene fluctuations in climate and biota recorded in the strata. Progressively greater concentrations and accumulation rates of mercury since ca. A.D. 1875 reflect deposition of anthropogenic mercury additions to the atmosphere. Within the Holocene record are numerous short intervals in which mercury concentrations and accumulation rates exceed the modern values. The highest mercury concentrations formed ca. 8 ka, coincident with a rapid change from cool, moist conditions to warm, dry conditions. A related change in flora from pine forest to prairie caused destruction of …


Paired Site Sampling For Soil Carbon Estimation – Western Australia, Edward Arnold Griffin, W H. Verboom, D G. Allen Feb 2003

Paired Site Sampling For Soil Carbon Estimation – Western Australia, Edward Arnold Griffin, W H. Verboom, D G. Allen

Natural resources research reports

This report describes a detailed paired site study at nine locations in the drier parts of south–western Australia representative of areas most recently cleared for agriculture. The pairing was of uncleared, short-term cleared and long-term cleared sites. The study provided samples for modelling soil organic carbon fluxes by CSIRO Land and Water. Analysis and interpretation of results from the samples collected and detailed soil morphology descriptions provide comprehensive documentation of the soil carbon and other soil parameters. This provides a basis for better understanding factors influencing soil carbon dynamics in soils in Western Australia, particularly in areas with sandy topsoils. …


Beaumont-Condingup Area : Catchment Appraisal 2002, A Alderman, Natural Heritage Trust (Australia) Feb 2003

Beaumont-Condingup Area : Catchment Appraisal 2002, A Alderman, Natural Heritage Trust (Australia)

Resource management technical reports

Using the Rapid Catchment Appraisal process, this report summarises current information for the Beaumont - Condingup area, east of Esperance. The object of the Rapid Catchment Appraisal is to assess the condition of, and future risks to agricultural and natural resources, and provide information for reducing those risks within geographic catchments and attempts to identify the most suitable options to manage these risks.


Groundwater Study Of The Bullaring Townsite, S Ghauri Feb 2003

Groundwater Study Of The Bullaring Townsite, S Ghauri

Resource management technical reports

A groundwater study was carried out in the townsite of Bullaring, Western Australia. This report describes the town and its catchment, the hydrogeological investigation characterising groundwater flow systems within the townsite, and recommends actions for managing salinity risk.


Understanding Relationships Between The 1998 Yangtze River Flood And Northeast Eurasian Blocking, Arthur N. Samel, Xin-Zhong Liang Jan 2003

Understanding Relationships Between The 1998 Yangtze River Flood And Northeast Eurasian Blocking, Arthur N. Samel, Xin-Zhong Liang

School of Earth, Environment and Society Faculty Publications

Severe summer monsoon flooding occurred along the Yangtze River Valley (YRV) in 1998. The heaviest precipitation fell during June 8-23 and July 20-29 and coincided with midtropospheric blocking over northeast Eurasia. An index based on the difference between Okhotsk High and west Pacific Low intensity is developed in this study to quantify blocking; analysis shows that blocking and equatorward displacement of the upper-tropospheric east Asian jet preceded (accompanied) the June (July) period. This suggests that heavy rainfall during each interval was caused by different atmospheric processes. An examination of joint variations in the index and YRV precipitation during 1958-1998 revealed …


Sediment Transport By Dry Ravel, Emmanuel Gabet Jan 2003

Sediment Transport By Dry Ravel, Emmanuel Gabet

Faculty Publications

Dry ravel is a general term that describes the rolling, bouncing, and sliding of individual particles down a slope and is a dominant hillslope sediment transport process in steep arid and semiarid landscapes. During fires, particles can be mobilized by the collapse of sediment wedges that have accumulated behind vegetation. On a daily basis, particles may be mobilized by bioturbation and by small landslides. Experiments on a dry ravel flume indicate that a basic expression of the momentum equation predicts the distance traveled by particles propelled down a rough surface. This equation is further elaborated to produce a nonlinear slope-dependent …


Magmatic Subsidence Of The East Pacific Rise (Epr) At 18˚14'S Revealed Through Fault Restoration Of Ridge Crest Bathymetry, S M. Carbotte, William B F Ryan, Wen Jin, Marie-Helene Cormier, Eric Bergmanis, John Sinton, Scott M. White Jan 2003

Magmatic Subsidence Of The East Pacific Rise (Epr) At 18˚14'S Revealed Through Fault Restoration Of Ridge Crest Bathymetry, S M. Carbotte, William B F Ryan, Wen Jin, Marie-Helene Cormier, Eric Bergmanis, John Sinton, Scott M. White

Faculty Publications

The fault restoration technique of De Chabalier and Avouac [1994] is applied to an ultra-highresolution bathymetry data set from the East Pacific Rise (EPR) at 18140S. Fault offsets are calculated and subtracted from the original seafloor bathymetry to examine the morphology of the unfaulted seafloor surface within an area encompassing the ridge axis 400 [1] 1600 m in dimension. The restored topography reveals a gently sloping seafloor 200 m wide, which slopes 5 inward toward the spreading axis. We attribute this inward sloping seafloor to subsidence within the axial trough due to subsurface magmatic deflation. The vertical deformation field extracted …


Semi-Analytical Stochastic Study Of Radionuclide Transport In The Saturated Zone Below Yucca Mountain, Xiaolong Hu, Craig Shirley, Jichun Wu, Hai Huang Jan 2003

Semi-Analytical Stochastic Study Of Radionuclide Transport In The Saturated Zone Below Yucca Mountain, Xiaolong Hu, Craig Shirley, Jichun Wu, Hai Huang

Publications (YM)

The objective of this study is to predict radionuclide solute transport process in the saturated zone below the Yucca Mountain project area. Based on a stochastic perturbation approach, a numerical method of moments has been developed and used to predict the mean, variance and upper bound of the radionuclide mass flux through a control plane 5-km downstream of the footprint of the repository. This study enhances the analysis of the effect of medium’s heterogeneity on solute transport prediction, especially on prediction uncertainty.


Sediment Detachment By Rain Power, Emmanuel Gabet, Thomas Dunne Jan 2003

Sediment Detachment By Rain Power, Emmanuel Gabet, Thomas Dunne

Faculty Publications

In interrill areas, overland flow is often incapable of detaching soil particles so detachment is primarily by raindrop impact. We derive a mathematical expression, rain power (R, W m−2), relating the energy expenditure of raindrops impacting a soil surface to the rate of detachment of soil particles. Rain power incorporates rainfall, hillslope, and vegetation characteristics and is modulated by flow depths. Rainfall simulation experiments on natural hillslopes were performed to measure detachment rates and across-slope flow depth distributions in surface runoff. Our results indicate that flow depths follow a Poisson distribution, and this observation is used to develop a dimensionless …


Sizes And Shapes Of 10-Ma Distal Fall Pyroclasts In The Ogallala Ggroup, Nebraska, William I. Rose, C. M. Riley, S. Dartevelle Jan 2003

Sizes And Shapes Of 10-Ma Distal Fall Pyroclasts In The Ogallala Ggroup, Nebraska, William I. Rose, C. M. Riley, S. Dartevelle

Department of Geological and Mining Engineering and Sciences Publications

Size distributions of distal ashfall particles from correlated 10-Ma layers in Nebraska, measured using laser diffraction methods, are lognormal with mode diameters of ∼90 mm. This ashfall is ∼100% bubble-wall shards of rhyolite glass and apparently represents a distal ashfall from an eruption 1400 km away. Measured terminal velocities of these ash particles are 0.2–18 cm/s, consistent with Stokes Law settling of spherical particles with diameters of 9–50 mm. Surface area of the ash particles, measured with gas adsorption, is 20–30 times the surface area of equivalent Stokes spheres. These results highlight the effects of shape and atmospheric drag in …