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Articles 51961 - 51990 of 59402
Full-Text Articles in Entire DC Network
Reconstruction Of Wetland Hydrology Dynamics Using Tree Rings, Allan P. Hascall Iii
Reconstruction Of Wetland Hydrology Dynamics Using Tree Rings, Allan P. Hascall Iii
Dissertations
Increment core samples were collected and examined to test the hypothesis that the history of punctuated or intermediate-term changes in wetland soil-moisture conditions can be reconstructed from the annual growth-ring record of trees. The hypothesis is based on plant physiological principles that indicate a relationship between water surplus stress and impaired physiological activity that could lead to reduced growth.
Sampling sites were selected for their ostensible historic hydrologic variability and the availability of documentation of hydrologic disturbances. A conceptual model was developed by which trees were sampled along a hydrotopographic gradient for comparison of radial stem growth in uplands versus …
Ice Transport In The Queen Elizabeth Islands, Canadian Arctic Using Detrital Fe Oxide Grain Composition, Duan Li
OES Theses and Dissertations
Nine Fe oxide mineral types (45pm-250pm) separated from 54 glacial and glaciomarine sediment samples from the Queen Elizabeth Islands (QEI) of Canada were analyzed for 12 elements by electron microprobe to determine the dispersal patterns of ice rafted debris in this area. Both cluster analysis and discriminant function analysis (DFA) on the chemical compositions were used to match each detrital Fe oxide grain to a source The entire QEI area can be subdivided into eight unique areas based on the elemental composition of the Fe oxide minerals. These subdivisions are similar to the source areas based on the assemblage of …
Biostratigraphic Analysis Of Southern Florida's Plio-Pleistocene Shell Beds, Dalton L. Rasmussen
Biostratigraphic Analysis Of Southern Florida's Plio-Pleistocene Shell Beds, Dalton L. Rasmussen
OES Theses and Dissertations
Four molluscan assemblage zones in southern Florida corresponding to the Pinecrest Sand Member of the Tamiami Formation, and the Caloosahatchee, Bermont and Fort Thompson shell beds were identified following quantitative and qualitative analyses of the fossil molluscan fauna. Twenty-eight bulk sediment samples collected from 16 localities across southern Florida were processed for fossil material, and yielded nearly 60,000 specimens belonging to 311 species. A Q-mode cluster analysis compared sediment samples on the basis of 188 species whose abundances had been converted to binary presence-absence form. The cluster analysis was run four times using the Jaccard and Dice similarity coefficients as …
40Ar/39 Ar Geochronology Of The Lowland Creek Volcanic Field And Its Temporal Relations With Other Eocene Volcanic Areas, Vladimir Olegovich Ispolatov
40Ar/39 Ar Geochronology Of The Lowland Creek Volcanic Field And Its Temporal Relations With Other Eocene Volcanic Areas, Vladimir Olegovich Ispolatov
OES Theses and Dissertations
Exposures of the Eocene Lowland Creek Volcanics (LCV) cover an area of 2000 km2 in southwestern Montana, and consist of basal elastic deposits, felsic tuffs, and felsic and intermediate lavas with an aggregate thickness of about 2 km. New 40Ar/39Ar dates show that volcanic activity lasted for at least 4.2 million years (52.7- 48.5 Ma), or even longer (4.5-4.7 million years: from 53.0-53.2 Ma to 48.5 Ma). During evolution of the volcanic field, early explosive volcanism was gradually replaced by extrusive activity. During the transition period (52.7-51.5 Ma), the two volcanic styles coexisted.
The evolution of …
Elevation As A Control Of Boulder Stream Formation In The Blue Ridge Province Of Virginia, Marc D. Zamkotowicz
Elevation As A Control Of Boulder Stream Formation In The Blue Ridge Province Of Virginia, Marc D. Zamkotowicz
OES Theses and Dissertations
Within four study areas in the Blue Ridge Mountains of Virginia, boulder streams formed by periglacial processes carpet the bottoms of most high-altitude first-order valleys. The geomorphic indicators of periglacial formation in these long, linear accumulations of bouldery colluvium - the presence of vertical clasts, gradational upper contacts with talus deposits, confinement within valleys, and hump-like cross sectional profiles - were present in all areas mapped and in most individual boulder streams. The minimum critical elevation for boulder stream formation increases from north to south across Virginia, from 150 m in elevation in northern Virginia to 1500 m in southwestern …
Middle Shoreface Intervals: Evidence Of Barred Nearshore Systems In He Stratigraphic Record, James V. Gravette
Middle Shoreface Intervals: Evidence Of Barred Nearshore Systems In He Stratigraphic Record, James V. Gravette
OES Theses and Dissertations
An interpretation for middle shoreface (MSF) intervals was developed by comparing MSF intervals from the Upper Cretaceous (Campanian) Blackhawk Formation, east-central Utah, with conceptual models proposed for modern nearshore areas. Specifically, MSF intervals identified within the Sunnyside Member were compared with MSF intervals identified within the Spring Canyon (Kamola and Van Wagoner, 1995) and the Aberdeen (Kamola, unpublished data) members.
A comparison of MSF interval data revealed that MSF intervals occur stratigraphically between upper and lower shore face deposits, disrupting the standard vertical succession for nearshore marine deposits (consisting of offshore, lower shore face, upper shore face, and foreshore deposits). …
The Effects Of Organic Matter Rich Topsoil On The Germination Growth And Metal Uptake Of Corn (Zea Mays) Grown In Flue Dust Contaminated Soil, Christopher Allen Impellitteri
The Effects Of Organic Matter Rich Topsoil On The Germination Growth And Metal Uptake Of Corn (Zea Mays) Grown In Flue Dust Contaminated Soil, Christopher Allen Impellitteri
OES Theses and Dissertations
The large biomass of corn (Zea mays) and promising results from a previous experiment (Chlopecka and Adriano, 1995) concerning metal uptake by corn indicate that corn may be a good candidate for phytoremediation of trace metal contaminated soil. Appling soil (acid, thermic, typic paleudult) was treated with increasing levels of a metal rich flue dust based on Zn concentration (0, 150, 300, 600, 1200, and 2400 mg/kg). Four replicates at each Zn treatment level were either limed to pH 6.3-6.5 and covered with a two inch thick layer of organic matter rich topsoil (OM), unlimed and covered with …
Rates, Timing, And Cyclicity Of Holocene Eolian Activity In North-Central United States: Evidence From Varved Lake Sediments, Walter E. Dean
Rates, Timing, And Cyclicity Of Holocene Eolian Activity In North-Central United States: Evidence From Varved Lake Sediments, Walter E. Dean
United States Geological Survey: Staff Publications
Most of the sediment components that accumulated in Elk Lake, northwestern Minnesota, during the Holocene are autochthonous or biogenic, delivered to the sediment-water interface on a seasonal schedule, preserved in distinct annual laminae (varves). The main allochthonous component is detrital clastic material, as measured by bulk-sediment concentrations of aluminum, sodium, potassium, titanium, and quartz, that enters the lake mostly as eolian dust. The eolian clastic influx to Elk Lake was considerably greater during the mid-Holocene (8–4 ka) than it has been for the past 4000 yr, when periods of increased eolian activity correspond to the time of the Little Ice …
Arkansas Soil Fertility Studies 1996, Wayne E. Sabbe
Arkansas Soil Fertility Studies 1996, Wayne E. Sabbe
Arkansas Agricultural Experiment Station Research Series
No abstract provided.
A Soil-Canopy-Atmosphere Model For Use In Satellite Microwave Remote Sensing, Venkataraman Lakshmi, Eric F. Wood, Bhaskar J. Choudhury
A Soil-Canopy-Atmosphere Model For Use In Satellite Microwave Remote Sensing, Venkataraman Lakshmi, Eric F. Wood, Bhaskar J. Choudhury
Faculty Publications
Regional and global scale studies of land-surface-atmosphere interactions require the use of observations for calibration and validation. In situ field observations are not representative of the distributed nature of land surface characteristics, and large-scale field experiments are expensive undertakings. In light of these requirements and shortcomings, satellite observations serve our purposes adequately. The use of satellite data in land surface modeling requires developing a hydrological model with a thin upper layer to be compatible with the nature of the satellite observations and that would evaluate the soil moisture and soil temperature of a thin layer close to the surface. This …
The Geodetic Signature Of The M8.0 Oct. 9, 1995, Jalisco Subduction Earthquake, Timothy I. Melbourne, I. Carmichael, C. Demets, K. Hudnut, O. Sanchez, J. Stock, G. Suarez, F. Webb
The Geodetic Signature Of The M8.0 Oct. 9, 1995, Jalisco Subduction Earthquake, Timothy I. Melbourne, I. Carmichael, C. Demets, K. Hudnut, O. Sanchez, J. Stock, G. Suarez, F. Webb
Faculty Scholarship for the Cascadia Hazards Institute
The October, 1995 Mw 8.0 Jalisco subduction earthquake has provided a thorough geodetic observation of the coseismic subduction process. An 11 station regional GPS network located directly onshore of the rupture demonstrates consistent vertical subsidence verified by tide gauge data and southwest-directed extension, with measured displacements reaching 1 meter. Unusually shallow and non-uniform faulting is required to explain the displacements. We determine that up to 5 meters of slip occurred within the upper 15 km of the thrust fault zone and 2 meters possibly as shallow as 8 km, and that slip was likely distributed in two main patches. The …
Kilauea Volcano Provides Hot Seismic Data For Joint Japanese-U.S. Experiment, Stephen R. Mcnutt, Y. Ida, B. A. Chouet, P. Okubo, J. Oikawa, G. Saccorotti
Kilauea Volcano Provides Hot Seismic Data For Joint Japanese-U.S. Experiment, Stephen R. Mcnutt, Y. Ida, B. A. Chouet, P. Okubo, J. Oikawa, G. Saccorotti
School of Geosciences Faculty and Staff Publications
A team of 25 researchers from the United States, Japan, and Italy joined the staff of the Hawaiian Volcano Observatory (HVO) from January 8 through February 9, 1996, to make the most detailed seismic recordings on Kilauea Volcano ever. One-hundred-sixteen portable seismographs were installed in and near Kilauea Crater in Hawaii Volcanoes National Park as a joint Japanese-U.S. research project to record volcanic earthquakes and tremor. The importance of these events has long been recognized, but their origin remains poorly understood due to inadequate network coverage and limitations of the analog instrumentation used in the past.
On February 1, a …
Salinity And Hydrology Of The Wamballup Swamp Catchment, R Ferdowsian, A T. Ryder
Salinity And Hydrology Of The Wamballup Swamp Catchment, R Ferdowsian, A T. Ryder
Resource management technical reports
No abstract provided.
Investigations On The Effect Of Grazing Intensity On The Transfer Of Radionuclides To Cow's Milk, G. Voight, C. Schotola, N. M.J. Crout, J. Absalom
Investigations On The Effect Of Grazing Intensity On The Transfer Of Radionuclides To Cow's Milk, G. Voight, C. Schotola, N. M.J. Crout, J. Absalom
All U.S. Government Documents (Utah Regional Depository)
No abstract provided.
A Gps Estimate Of Relative Motion Between North And South America, Timothy H. Dixon, Ailin Mao
A Gps Estimate Of Relative Motion Between North And South America, Timothy H. Dixon, Ailin Mao
School of Geosciences Faculty and Staff Publications
GPS velocity data are used to estimate the Euler vector describing rigid body motion of North America relative to South America. Assuming the boundary between the North and South American plates is located near the Fifteen Twenty fracture zone in the equatorial Atlantic, the Euler vector predicts extension across the Royal Trough up to 1 mm/yr, and convergence across the Barracuda Ridge at about 2 mm/yr, in agreement with geological estimates averaged over tens of millions of years. Further west, convergence between North and South America at rates up to 8 mm/yr may contribute to deformation of the Caribbean plate …
Enclaves In The Cadillac Mountain Granite (Coastal Maine): Samples Of Hybrid Magma From The Base Of The Chamber, R. A. Wiebe, Diane R. Smith, M. Sturm, E. M. King, M. S. Seckler
Enclaves In The Cadillac Mountain Granite (Coastal Maine): Samples Of Hybrid Magma From The Base Of The Chamber, R. A. Wiebe, Diane R. Smith, M. Sturm, E. M. King, M. S. Seckler
Earth and Environmental Geosciences Faculty Research
The Cadillac Mountain intrusive complex is dominated by the Cadillac Mountain granite and a 2–3 km thick section of interlayered gabbroic, dioritic and granitic rocks which occurs near the base of the granite. The layered rocks record hundreds of injections of basaltic magma that ponded on the chamber floor and variably interacted with the overlying silicic magma. Magmatic enclaves, ranging in composition from 55 to 78 wt % SiO2, are abundant in granite above the layered mafic rocks. The most mafic enclaves are highly enriched in incompatible elements and depleted in compatible elements. Their compositions can be best …
Bulletin 4333 - Furrow Sowing On Water Repellent Soils, Paul Blackwell, Grant Morrow
Bulletin 4333 - Furrow Sowing On Water Repellent Soils, Paul Blackwell, Grant Morrow
Bulletins 4000 -
This Bulletin discusses the benefits that furrow sowing brings to crop growth and production on water repellent sand, based on research and farm observations in Western Australian. By understanding the benefits and risks of several key processes, producers can better evaluate the potential role of furrow sowing in combating water repellency. This is true whether one is using direct drilling, no-till (narrow points or discs) or zero till (single, double or triple disc openers) methods.
The Columbia Slough, Scott A. Wells
The Columbia Slough, Scott A. Wells
Civil and Environmental Engineering Faculty Publications and Presentations
This report was written in an attempt to provide the public and Bureau of Environmental Services Staff with a summary of work accomplished on the Columbia Slough system by Portland State University and other consultants working on the Slough over the last 6 years. An attempt was made to create an easy-to-read report with important overviews of the "big picture", glossary of definitions, index, and further details to assist in technology transfer.
What Leading Alfalfa Producers Do To Produce Quality Hay, Jimmy C. Henning, Garry D. Lacefield, Buddy Sims
What Leading Alfalfa Producers Do To Produce Quality Hay, Jimmy C. Henning, Garry D. Lacefield, Buddy Sims
Kentucky Alfalfa and Stored Forage Conference
Alfalfa is the highest quality forage legume crop grown in Kentucky and is the number one cash hay crop. Hay raised by Kentucky farmers has been recognized for its quality at local, state (state fair and Kentucky Alfalfa Conference), and national (American Forage and Grassland Council) hay contests. The testing records of the Kentucky Department of Agriculture also document the high quality alfalfa hay of Kentucky. However, little has been written about the farm practices used to produce high quality alfalfa hay in Kentucky. The current practices of top hay growers may be helpful in defining the options available to …
Grazing Alfalfa In Tennessee: Experiences And Opportunities, Gary Bates
Grazing Alfalfa In Tennessee: Experiences And Opportunities, Gary Bates
Kentucky Alfalfa and Stored Forage Conference
Animal agriculture in the southeastern U.S. is based on forages. This area has the advantage over all other sections of the nation in forage production. From Kentucky to south Florida, with a little planning forage can be grown almost 12 months a year. Forage programs in Tennessee and Kentucky are based primarily around cool-season grasses such as tall fescue and orchardgrass. These grasses grow over a long portion of the year. In fact, producers have to deal with excess forage production during the spring and fall (Fig. 1). The quality and quantity of forage during these times of the year …
Grazing Alfalfa In Lincoln County, Dan Grigson
Grazing Alfalfa In Lincoln County, Dan Grigson
Kentucky Alfalfa and Stored Forage Conference
Alfalfa grazing is becoming an important practice for our county's large livestock enterprise. Both dairy and beef producers use alfalfa grazing in various parts of their feeding operations. Lincoln County farmers have a reputation for being good forage producers and have over the years produced good yields and good quality alfalfa. Most producers realize that good forage leads to better profits for their livestock enterprises. That's very important to us as the livestock business generates over $21 million in cash receipts annually.
Alfalfa Seed Production In The Western U.S., Garry D. Lacefield
Alfalfa Seed Production In The Western U.S., Garry D. Lacefield
Kentucky Alfalfa and Stored Forage Conference
Alfalfa is the primary forage for the dairy industry in the United States and provides a majority of the nutrients and energy needs for other classes of livestock including beef cattle, horses and sheep.
In order to maximize forage yield, quality and persistence, one should start with high quality seed. Seed must be free of noxious weeds, have a purity higher than 99.5 percent, a germination of 90 percent or higher and true to the variety stated.
Over 80% of the alfalfa seed was grown in the Great Plains and Rocky Mountain states prior to 1948. This was mostly uncertified, …
Do's And Don'ts Of Alfalfa Round Baled Silage, Michael Collins
Do's And Don'ts Of Alfalfa Round Baled Silage, Michael Collins
Kentucky Alfalfa and Stored Forage Conference
Round baled silage provides an option for outside storage of round bales that protects them from weathering. With shorter field exposure times, silage can dramatically increase forage quality compared with hay. Harvest problems caused by wet weather and/or poor drying conditions during spring and for the freeze-down harvest during autumn could be alleviated by incorporating silage into the harvest system.
Alfalfa Hay: Quality Makes The Difference, Garry D. Lacefield, Jimmy C. Henning
Alfalfa Hay: Quality Makes The Difference, Garry D. Lacefield, Jimmy C. Henning
Kentucky Alfalfa and Stored Forage Conference
Alfalfa "Queen of the Forage Crops" is one of the most important forage legumes grown in the U.S. It can be grown over a wide range of soil and climatic conditions, it has the highest yield potential and the highest feeding values of all adapted perennial forage legumes. Alfalfa is a versatile crop which can be used for pasture, hay, silage, green-chop, soil improvements and · human consumption (sprouts, etc.).
A Solution To Some Spring-Seeded Alfalfa Problems, Paul C. Vincelli
A Solution To Some Spring-Seeded Alfalfa Problems, Paul C. Vincelli
Kentucky Alfalfa and Stored Forage Conference
One of the most important assignments I received when I assumed this position in 1990 was to address the question, "What is the cause of seeding failure when alfalfa is spring-seeded into soils that remain wet after seeding?" Six years of laboratory and field work have finally borne fruit. Based on our research, we can confidently present Kentucky alfalfa producers with three conclusions and a recommendation.
Manure On Alfalfa: Why, When, And How Much?, Monroe Rasnake
Manure On Alfalfa: Why, When, And How Much?, Monroe Rasnake
Kentucky Alfalfa and Stored Forage Conference
Manure is an excellent source of nutrients for growing crops. Its' value has been recognized for thousands of years. Before the development of chemical fertilizers, it served as the primary source of nutrients. It has decreased in importance as a nutrient source in this century and in some cases has become a disposal problem. This has led many farmers to consider using it on legume crops such as alfalfa that don't need to have nitrogen added, but will utilize it and other . nutrients in relatively large amounts. The first question to be considered, then, is why apply manure to …
Controlling Weeds In New Seedings And Established Stands, Jonathan D. Green
Controlling Weeds In New Seedings And Established Stands, 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. Weeds may reduce forage yield by competing for water, sunlight and nutrients. For example, yield obtained from the first cutting of alfalfa can be significantly reduced by a heavy infestation of common chickweed. In addition to yield losses, weeds can also lower forage quality, increase the incidence of disease and insect problems, cause premature stand loss, and create harvesting problems. In some cases weeds are unpalatable to livestock or may be poisonous.
What I'Ve Learned From Three Years Of Intensive Experience With No-Till Alfalfa, Jimmy C. Henning, Garry D. Lacefield, Andy Anderson
What I'Ve Learned From Three Years Of Intensive Experience With No-Till Alfalfa, Jimmy C. Henning, Garry D. Lacefield, Andy Anderson
Kentucky Alfalfa and Stored Forage Conference
Three years ago, a project was begun to better understand the 'hands-on' aspects of no-till establishment of legumes especially alfalfa into fescue sod. Although no-till drills and technology had been around for nearly two decades, farmer feedback on the success of no-till establishment was not uniformly good. The University of Kentucky initiated a program called the 'Establishment Initiative' in partnership with seed companies and Agco-Tye to conduct no-till establishment demonstrations of no-till establishment. These demonstrations focused on getting alfalfa and red clover established into fescue sod which had been suppressed with herbicides. The following are some of the lessons learned.
Foreword [1997], Garry D. Lacefield
Foreword [1997], Garry D. Lacefield
Kentucky Alfalfa and Stored Forage Conference
This is the front matter of the proceedings.
Core-Log-Seismic Integration As A Framework For Determining The Basin-Wide Significance Of Regional Reflectors In The Eastern Equatorial Pacific, Stephen F. Bloomer, Larry A. Mayer
Core-Log-Seismic Integration As A Framework For Determining The Basin-Wide Significance Of Regional Reflectors In The Eastern Equatorial Pacific, Stephen F. Bloomer, Larry A. Mayer
Affiliate Scholarship
ODP Leg 138 in the eastern equatorial Pacific (EEP) provided a unique opportunity to understand the paleoceanographic significance of seismic reflectors in this climatically sensitive region. Carefully offset multiple cores were spliced into a complete stratigraphic section for the upper 250 m at each site and accurate, astronomically tuned time scales were generated from these composites. Well log data provided a means to correct composite depths to true depths as well as density and velocity data for the generation of synthetic seismograms. These synthetic seismograms were used to determine the paleoceanographic significance of regionally traceable reflectors by linking variations in …