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Evaporation Reduction Potential In An Undisturbed Soil Irrigated With Surface Drip And Sand Tube Irrigation, Masoud Meshkat, Richard C. Warner, Stephen R. Workman Jan 2000

Evaporation Reduction Potential In An Undisturbed Soil Irrigated With Surface Drip And Sand Tube Irrigation, Masoud Meshkat, Richard C. Warner, Stephen R. Workman

Biosystems and Agricultural Engineering Faculty Publications

The efficiency of drip irrigation is highly dependent on evaporation losses occurring from the constantly saturated soil beneath emitters. Advent of subsurface drip irrigation is in part an approach to curb this inefficiency. An irrigation method, Sand Tube Irrigation (STI), is proposed to increase the efficiency of “Normal” surface applied drip Irrigation (NI method) on permanent tree crops without the need for burying the irrigation tubing. The sand tube consists of removing a soil core beneath the emitter and filling the void with coarse sand. A weighing lysimeter was constructed in the laboratory and instrumented to directly measure temporal evaporation …


Mowing, Dethatching, Coring, And Rolling Kentucky Lawns, A. J. Powell Jr. Jan 2000

Mowing, Dethatching, Coring, And Rolling Kentucky Lawns, A. J. Powell Jr.

Agriculture and Natural Resources Publications

Good lawn care takes more than just mowing and chemical treatments. To develop quality turf, you need correct mowing techniques and may occasionally need to dethatch, core, or roll your lawn.


Improving Turf Through Renovation, A. J. Powell Jr. Jan 2000

Improving Turf Through Renovation, A. J. Powell Jr.

Agriculture and Natural Resources Publications

Turf generally can be improved through proper mowing, fertilizing, watering, and pest control applications. With some turf problems, however, the only solution is re-establishment, using one of two methods:

  • The conventional method, which involves destroying the sod, tilling the soil, and replanting.
  • Renovation, which involves replanting without completely tilling the soil and often without destroying all existing vegetation.

Advantages of conventional tillage over renovation:

  • Control of weeds and undesirable grass may be more complete.
  • Surface depressions or humps can be removed, resulting in a smoother soil surface.
  • Large quantities of organic matter or sand can be mixed into the surface …


Analysis Of Selected Herbicide Metabolites In Surface And Ground Water Of The United States, Elisabeth A. Scribner, E. M. Thurman, Lisa R. Zimmerman Jan 2000

Analysis Of Selected Herbicide Metabolites In Surface And Ground Water Of The United States, Elisabeth A. Scribner, E. M. Thurman, Lisa R. Zimmerman

United States Geological Survey: Staff Publications

One of the primary goals of the US Geological Survey (USGS) Laboratory in Lawrence, Kansas, is to develop analytical methods for the analysis of herbicide metabolites in surface and ground water that are vital to the study of herbicide fate and degradation pathways in the environment. Methods to measure metabolite concentrations from three major classes of herbicides ─ triazine, chloroacetanilide and phenyl-urea ─ have been developed. Methods for triazine metabolite detection cover nine compounds: six compounds are detected by gas chromatography/mass spectrometry; one is detected by high-performance liquid chromatography with diode-array detection; and eight are detected by liquid chromatography/mass spectrometry. …


Groundwater-Level Changes In Nebraska Predevelopment To 1954, University Of Nebraska - Lincoln Jan 2000

Groundwater-Level Changes In Nebraska Predevelopment To 1954, University Of Nebraska - Lincoln

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Buffalo County Test Hole Logs, Vincent H. Dreeszen Jan 2000

Buffalo County Test Hole Logs, Vincent H. Dreeszen

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Devitrification Of Volcanic Glasses In Konya Volcanic Units, Turkey, Zehra Karakaş, Selahatti̇n Kadi̇r Jan 2000

Devitrification Of Volcanic Glasses In Konya Volcanic Units, Turkey, Zehra Karakaş, Selahatti̇n Kadi̇r

Turkish Journal of Earth Sciences

The study area is composed of volcanic, sedimentary and volcano-sedimentary units, which are exposed south and southwest of the city of Konya. XRD analysis indicates that the volcanic units contain halloysite, kaolinite, smectite, illite and sepiolite type clay minerals and opal-CT, feldspar, quartz, minamiite and jarosite type non-clay minerals. SEM studies show that volcanic glasses, which are the main component of the volcanic units, appeared as curviplanar, vesicular-planar and in highly fractured shapes. Fractures and dissolution voids of the volcanic glasses are generally filled by hexagonal kaolinite, fibrous halloysite and smectite. Mineralogical and micromorphological observations indicate that clay minerals were …


Effect Of Magnesium And Sulfur Fertilization Of Alfalfa, Kenneth L. Wells, James E. Dollarhide Jan 2000

Effect Of Magnesium And Sulfur Fertilization Of Alfalfa, Kenneth L. Wells, James E. Dollarhide

Soil Science News and Views

In response to concerns that high yields of alfalfa need to be fertilized with sulfur (S) because of soil depletion of S and less S entering the soil from atmospheric fallout, studies were conducted during 1998-1999, to test for S response by alfalfa. Additionally, alfalfa was tested for magnesium (Mg) response because previous hay analysis from the study site had shown very low levels of Mg.


Irrigated Field Crop Acres In Kentucky, Lloyd W. Murdock Jan 2000

Irrigated Field Crop Acres In Kentucky, Lloyd W. Murdock

Soil Science News and Views

Irrigation in Kentucky has always been limited. This is due to a limited water supply in many parts of Kentucky and the high amount of rainfall in the state which reduces the chances for a consistent profitable response to field crops.


Soil Testing For Agronomic And Environmental Uses, William O. Thom, Frank J. Sikora Jan 2000

Soil Testing For Agronomic And Environmental Uses, William O. Thom, Frank J. Sikora

Soil Science News and Views

Soil testing is a program that includes taking samples from a field or site, performing a laboratory analysis, and making recommendations for lime and crop nutrients. Good results from this program depend on several supporting factors: (I) obtaining samples representative of the soil in a field area or site; (2) using good techniques in the laboratory that give accurate indications of the nutrient status of the sampled area; and (3) having an extensive data base for making lime and nutrient recommendations from the analytical results.


Drawdown Of Soil Test Phosphorus And Potassium Levels By Alfalfa, Kenneth L. Wells, James E. Dollarhide Jan 2000

Drawdown Of Soil Test Phosphorus And Potassium Levels By Alfalfa, Kenneth L. Wells, James E. Dollarhide

Soil Science News and Views

Alfalfa hay production removes large amounts of phosphorus (P) and potassium (K) from soils. Because of this, there is always interest in the reduction of soil test phosphorus (STP) and soil test potassium (STK) levels by high-yielding alfalfa. Periodic soil sampling for 2 years during an on-farm· fertilizer study on a high yielding alfalfa field provided an insight into this.


Coal Resources Of The Lower Elkhorn Coal Bed In Eastern Kentucky, Ernest E. Thacker, Gerald A. Weisenfluh, William M. Andrews Jr., John K. Hiett Jan 2000

Coal Resources Of The Lower Elkhorn Coal Bed In Eastern Kentucky, Ernest E. Thacker, Gerald A. Weisenfluh, William M. Andrews Jr., John K. Hiett

Map and Chart--KGS

This chart is one of a series that shows the regional characteristics of the Lower Elkhorn coal. The maps were prepared as part of the U.S. Geological Survey's Natural Coal Assessment Program, which compiles regional maps and databases that provide a comprehensive assessment of the most important coal beds in the nation. The Lower Elkhorn coal is one of the leading producers in the state of Kentucky and has, in some areas, a reputation as an excellent metallurgical-grade coal. It is known locally as the Pond Creek, Imboden, Path Fork, Blue Gem, Straight Creek, Bruin or Vires coal bed. This …


Mining Geology Of The Lower Elkhorn Coal, Stephen F. Greb, Gerald A. Weisenfluh Jan 2000

Mining Geology Of The Lower Elkhorn Coal, Stephen F. Greb, Gerald A. Weisenfluh

Map and Chart--KGS

The Lower Elkhorn (and its equivalents) is one of the leading producers of coal in the Eastern Kentucky Coal Field with 12 to 18 million short tons of annual production between 1974 and 1996, according to the Kentucky Department of Mines and Minerals. Stratigraphically, the coal occurs in the lower part of the Pikeville Formation of the Breathitt Group (Fig. 1), which was previously part of the Breathitt Formation (Chesnut, 1992). The coal occurs from 150 to 300 ft above the base of a thick coarsening-upward sequence containing the Betsie Shale and from 250 to 450 ft beneath the base …


Coal Resources Of The Springfield Coal Bed In Western Kentucky, William M. Andrews Jr., Robert E. Andrews, John K. Hiett Jan 2000

Coal Resources Of The Springfield Coal Bed In Western Kentucky, William M. Andrews Jr., Robert E. Andrews, John K. Hiett

Map and Chart--KGS

Historically, the Springfield (Western Kentucky No. 9) coal bed has been the leading source of production in the Western Kentucky Coal Field. The Springfield coal is known for its lateral continuity in terms of both thickness and coal quality. It is estimated to have the largest original and remaining resource in the Western Kentucky Coal Field (Greb and others, 1992).


Total Coal Thickness Of The Fire Clay And Fire Clay Rider Coals In Eastern Kentucky, Ernest E. Thacker, Gerald A. Weisenfluh, Stephen F. Greb, Jeffery A. Esterle Jan 2000

Total Coal Thickness Of The Fire Clay And Fire Clay Rider Coals In Eastern Kentucky, Ernest E. Thacker, Gerald A. Weisenfluh, Stephen F. Greb, Jeffery A. Esterle

Map and Chart--KGS

This map is one of a series that shows the regional characteristics of the Fire Clay coal zone. The maps were prepared as part of the U.S. Geological Survey's National Coal Assessment Program, which compiles regional maps and databases that provide a comprehensive assessment of the most important coal beds in the nation. Within the zone, the Fire Clay coal is the most economically important bed and is one of the leading producers in the state of Kentucky. It is known for a persistent flint-clay parting that is believed to be of volcanic origin. This map represents the total coal …


Coal Resources Of The Upper Elkhorn No. 3b Coal (Upper Bed) In Eastern Kentucky, Jeffery A. Esterle, Ernest E. Thacker, Gerald A. Weisenfluh, John K. Hiett Jan 2000

Coal Resources Of The Upper Elkhorn No. 3b Coal (Upper Bed) In Eastern Kentucky, Jeffery A. Esterle, Ernest E. Thacker, Gerald A. Weisenfluh, John K. Hiett

Map and Chart--KGS

This chart is one of a series that shows the regional characteristics of the Upper Elkhorn No. 3 coal zone. The maps and charts were prepared as part of the U.S. Geological Survey's National Coal Assessment Program, which compiles regional maps and databases that provide a comprehensive assessment of the most important coal beds in the nation. The Upper Elkhorn No. 3 coal zone has been one of the leading producers in the state of Kentucky and, in some areas, is of very high quality. Bed stratigraphy within the Upper Elkhorn No. 3 zone and thickness of the No. 3A …


Mapped Karst Ground-Water Basins In The Bowling Green 30 X 60 Minute Quadrangle, Joseph A. Ray, James C. Currens Jan 2000

Mapped Karst Ground-Water Basins In The Bowling Green 30 X 60 Minute Quadrangle, Joseph A. Ray, James C. Currens

Map and Chart--KGS

This map shows karst ground-water basins in the Bowling Green quadrangle, determined primarily by ground-water tracer studies. It can be used to quickly identify the ground-water basins and springs to which a site may drain. Major springs and the relative size of their catchment areas can be evaluated for potential as water supplies. The map also serves as a geographic index to literature on karst ground water in the area.


Nebraska Information, Oregon Trail, Station Sites, University Of Nebraska - Lincoln Jan 2000

Nebraska Information, Oregon Trail, Station Sites, University Of Nebraska - Lincoln

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Small-Scale Variability Of Groundwater-Lake Interaction At Shingobee Lake, Minnesota, Hans F. Kishel Jan 2000

Small-Scale Variability Of Groundwater-Lake Interaction At Shingobee Lake, Minnesota, Hans F. Kishel

Theses and Dissertations

Groundwater discharge is an important contributor to the water budget of a lake. The variability of hydraulic parameters of lake and groundwater systems causes difficulties in estimating the contribution of groundwater to a lake water budget. This study attempts to show that amount of variability for a small portion of the lake and shore (8 x 15 meter section, starting approximately five meters from shore and extending nine meters into the lake).

Piezometers were installed at a depth of one half and one meter in nests at 70 locations in the rectangular study site. Water levels were collected from the …


Small-Scale Magnetic Flux Ropes In The Solar Wind, M. B. Moldwin, S. Ford, Ronald P. Lepping, James A. Slavin, Adam Szabo Jan 2000

Small-Scale Magnetic Flux Ropes In The Solar Wind, M. B. Moldwin, S. Ford, Ronald P. Lepping, James A. Slavin, Adam Szabo

Aerospace, Physics, and Space Science Faculty Publications

Small-scale magnetic flux ropes have been discovered in the solar wind at 1 AU in observations from the IMP 8 and WIND spacecraft. These small magnetic structures (diameter of 270 R(E), on average) have some similar properties to magnetic clouds (diameters of 0.2 -0.3 AU or about 6000 - 8000 R(E)), which are well known large-scale magnetic flux ropes, but have durations of 10s of minutes as opposed to many hours or days for most magnetic clouds. The presence of these small helical field structures suggests that solar wind flux ropes may have a wide-range of scale sizes, or possibly …


Oxygen Isotopes And Metolachlor Residues In Water Samples From A Portion Of The Canajoharie Creek Watershed, Central New York, John M. Nadeau Jan 2000

Oxygen Isotopes And Metolachlor Residues In Water Samples From A Portion Of The Canajoharie Creek Watershed, Central New York, John M. Nadeau

Geology Theses and Dissertations

Increased ground and surface water contamination has fueled the need for a better understanding of factors affecting hydrogeological settings. Seasonal variability in the recharge of an aquifer can affect the rate and amount of contamination that can occur. Stable isotopes have been previously investigated as tracers to determine flow paths of the water and contaminants. In this study, oxygen isotopes were used to determine the factors that influence seasonal variations in ground and surface water, such as well location, aquifer type, surface water sites, and soil type. Samples were collected from different locations around the Canajoharie Field Site, including wells …


Upper Cretaceous Eclogite-Facies Metamorphic Rocks From The Biga Peninsula, Northwest Turkey, Aral İ. Okay, Muharrem Satir Jan 2000

Upper Cretaceous Eclogite-Facies Metamorphic Rocks From The Biga Peninsula, Northwest Turkey, Aral İ. Okay, Muharrem Satir

Turkish Journal of Earth Sciences

Medium-grade metamorphic rocks crop out over a large area under the Neogene sedimentary and volcanic rocks in the central Biga Peninsula in northwest Turkey. These Çamlıca metamorphics consist dominantly of quartz-micaschists with minor calc-schist, marble, quartzite and metabasite. Some of the metabasites in the Çamlıca metamorphics preserve an early eclogite-facies mineral assemblage of garnet + omphacite + glaucophane + rutile ± paragonite, strongly overprinted by greenschist-facies mineral assemblages. The conditions of the eclogite-facies metamorphism have been determined as 510 ± 50°C temperatures and a minimum pressure of 11 kbar, based on the garnet-clinopyroxene Fe-Mg partitioning and the jadeite content of …


Mercury Bioaccumulation In Fish In A Region Affected By Historic Gold Mining: The South Yuba River, Deer Creek, And Bear River Watersheds, California, 1999, Jason T. May, Roger L. Hothem, Charles N. Alpers, Matthew A. Law Jan 2000

Mercury Bioaccumulation In Fish In A Region Affected By Historic Gold Mining: The South Yuba River, Deer Creek, And Bear River Watersheds, California, 1999, Jason T. May, Roger L. Hothem, Charles N. Alpers, Matthew A. Law

United States Geological Survey: Publications

Mercury that was used historically for gold recovery in mining areas of the Sierra Nevada continues to enter local and downstream water bodies, including the Sacramento–San Joaquin Delta and the San Francisco Bay of northern California. Methylmercury is of particular concern because it is the most prevalent form of mercury in fish and is a potent neurotoxin that bioaccumulates at successive trophic levels within food webs. In April 1999, the U.S. Geological Survey, in cooperation with several other agencies—the Forest Service (U.S. Department of Agriculture), the Bureau of Land Management, the U.S. Environmental Protection Agency, the California State Water Resources …


Mercury Contamination From Historic Gold Mining In California, Charles N. Alpers, Michael P. Hunerlach Jan 2000

Mercury Contamination From Historic Gold Mining In California, Charles N. Alpers, Michael P. Hunerlach

United States Geological Survey: Publications

Mercury contamination from historic gold mines represents a potential risk to human health and the environment. This fact sheet provides background information on the use of mercury in historic gold mining and processing operations in California, and describes a new USGS project that addresses the potential risks associated with mercury from these sources, with emphasis on historic hydraulic mining areas. Miners used mercury (quicksilver) to recover gold throughout the western United States at both placer (alluvial) and hardrock (lode) mines. The vast majority of mercury lost to the environment in California was from placer-gold mines, which used hydraulic, drift, and …


Metals Transport In The Sacramento River, California, 1996–1997 Volume 2: Interpretation Of Metal Loads, Charles N. Alpers, Ronald C. Antweiler, Howard E. Taylor, Peter D. Dileanis, Joseph L. Domagalski Jan 2000

Metals Transport In The Sacramento River, California, 1996–1997 Volume 2: Interpretation Of Metal Loads, Charles N. Alpers, Ronald C. Antweiler, Howard E. Taylor, Peter D. Dileanis, Joseph L. Domagalski

United States Geological Survey: Publications

Metals transport in the Sacramento River, northern California, from July 1996 to June 1997 was evaluated in terms of metal loads from sam-ples of water and suspended colloids that were collected on up to six occasions at 13 sites in the Sacramento River Basin. Four of the sampling periods (July, September, and November 1996; and May–June 1997) took place during relatively low-flow conditions and two sampling periods (December 1996 and January 1997) took place during high-flow and flooding conditions, respec-tively. This study focused primarily on loads of cadmium, copper, lead, and zinc, with secondary emphasis on loads of aluminum, iron, …


Dating Marine Terraces With Relative-Age And Correlated-Age Methods, Daniel R. Muhs Jan 2000

Dating Marine Terraces With Relative-Age And Correlated-Age Methods, Daniel R. Muhs

United States Geological Survey: Staff Publications

Coastal landforms, and particularly emergent marine terraces, a re amongt he most importantg eomorphicfe aturesi n studieso f Quaternarys eal evel fluctuationsa nd neotectonics. A general model, first articulated by Alexander (1953) and borne out by detailedr ecent studieso n many coastlinesi,s that emergent flights of erosional terraces and coral reefs (Fig. 1) are the resulto f glacioeustaticallyc ontrolledf luctuations of global sea level superimposed on steady uplift. Similiarity of U-series ages of coral from both constructional reefsi n the tropicsa nd erosionalt erracesi n midlatitudesh as provided a rigorous test of this model (Mesolella and others, 1969; Bloom and …


Ecogeochemistry Of The Subsurface Food Web At Ph 0–2.5 In Iron Mountain, California, U.S.A., Eleanora I. Robbins, Teresa M. Rodgers, Charles N. Alpers, D. Kirk Nordstrom Jan 2000

Ecogeochemistry Of The Subsurface Food Web At Ph 0–2.5 In Iron Mountain, California, U.S.A., Eleanora I. Robbins, Teresa M. Rodgers, Charles N. Alpers, D. Kirk Nordstrom

United States Geological Survey: Staff Publications

Pyrite oxidation in the underground mining environment of Iron Mountain, California, has created the most acidic pH values ever reported in aquatic systems. Sulfate values as high as 120 000 mg 1-1 and iron as high as 27600mg 1-1 have been measured in the mine water, which also carries abundant other dissolved metals including Al, Zn, Cu, Cd, Mn, Sb and Pb. Extreme acidity and high metal concentrations apparently do not preclude the presence of an underground acidophilic food web, which has developed with bacterial biomass at the base and heliozoans as top predators. Slimes, oil-like films, flexible …


Nutrients In Groundwaters Of The Conterminous United States, 1992-1995, Bernard Nolan, Jeffrey Stoner Jan 2000

Nutrients In Groundwaters Of The Conterminous United States, 1992-1995, Bernard Nolan, Jeffrey Stoner

United States Geological Survey: Staff Publications

Results of a national water quality assessment indicate that nitrate is detected in 71% of groundwater samples, more than 13 times as often as ammonia, nitrite, organic nitrogen, and orthophosphate, based on a common detection threshold of 0.2 mg/L. Shallow groundwater (typically 5 m deep or less) beneath agricultural land has the highest median nitrate concentration (3.4 mg/L), followed by shallow groundwater beneath urban land (1.6 mg/L) and deeper groundwater in major aquifers (0.48 mg/L). Nitrate exceeds the maximum contaminant level, 10 mg/L as nitrogen, in more than 15% of groundwater samples from 4 of 33 major aquifers commonly used …


Biostratigraphic Data (Mammalia And Palynology) From The Upper Miocene İncesu Formation At Düzyayla (Hafik-Sivas, Central Anatolia), Funda Akgün, Tanju Kaya, Ann Forsten, Zeki̇ Atalay Jan 2000

Biostratigraphic Data (Mammalia And Palynology) From The Upper Miocene İncesu Formation At Düzyayla (Hafik-Sivas, Central Anatolia), Funda Akgün, Tanju Kaya, Ann Forsten, Zeki̇ Atalay

Turkish Journal of Earth Sciences

The Upper Miocene İncesu formation, widely exposed in Düzyayla (Hafik-Sivas), consists of mudstones, conglomerates, lacustrine limestones and lignite. The İncesu formation overlies the gypsiferous Hafik formation of controversial Middle Miocene or Oligocene ages. The mammalian fauna of the lignite horizon includes Hipparion sp., Ceratotherium neumayri (Osborn), Deinotherium giganteum Kaup, Choerolophodon pentelici (Gaudry & Lartet), Adcrocuta cf. eximia (Roth & Wagner), Oioceros wegneri Andree, Helladotherium duvernoyi Gaudry & Lartet and Microstonyx erymanthius (Roth & Wagner), which indicate a Turolian (Late Miocene) age. The palynological assemblage of the lignite is apparently represented by 27 genera and 39 species. Four genera and four …


Mining Geology Of Coals In Western Kentucky, Stephen F. Greb, David A. Williams Jan 2000

Mining Geology Of Coals In Western Kentucky, Stephen F. Greb, David A. Williams

Map and Chart--KGS

Each of the most heavily mined coal seams in the Western Kentucky Coal Field, as indicated by analyses, mine visits, and discussions with mine inspectors and engineers, has its own roof and floor characteristics. Also, because roof rocks above several of the seams are laterally continuous (especially in the Carbondale Formation), roof characteristics related to rock type are often widespread and continuous between mines. This chart discusses the mining geology of three western Kentucky coal beds, highlighted on the stratigraphic column shown in Figure 1.

Additional mining obstacles that can affect all coal beds and roof strata are (1) tectonic …