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Late Season Supplemental Nitrogen On Double-Cropped Soybeans, Curt Judy, Lloyd W. Murdock Jan 1998

Late Season Supplemental Nitrogen On Double-Cropped Soybeans, Curt Judy, Lloyd W. Murdock

Soil Science News and Views

Soybeans produce their own nitrogen for crop growth with the aid of nitrogen fixing bacteria in the soil that infect the soybean root and form nodules which contain the bacteria. This is a symbiotic relationship that benefits both the plant and the bacteria. The bacteria are able to take atmospheric nitrogen and convert it into a form of nitrogen that the plant can use. Much of the nitrogen requirement for soybean production begins at seed development. Soybean physiology studies suggest that the amount of nitrogen supplied for the soybean plant from fixation in the nodules is less than the potential …


Kentucky's Coal Industry: Historical Trends And Future Opportunities, Gerald A. Weisenfluh, James C. Cobb, John C. Ferm, Carol L. Ruthven Jan 1998

Kentucky's Coal Industry: Historical Trends And Future Opportunities, Gerald A. Weisenfluh, James C. Cobb, John C. Ferm, Carol L. Ruthven

Information Circular--KGS

Coal has been produced in Kentucky since the late 18th century. In the early years, all mining was by underground methods, but surface mining became the dominant method during and after World War II. In recent years, surface-mine production in both fields has decreased while underground mining has increased.

In the last half of this century, the traditional steam coal market for locomotives has virtually disappeared, leaving electric power generation and coking coal for the steel industry as the principal markets. More than half of all coal produced in the State has been produced in the last 25 years. Whether …


Solute And Bacterial Transport Through Partially-Saturated Intact Soil Blocks, Edmund Perfect, Mark S. Coyne, Michael C. Sukop, Gerald R. Haszler, Virgil L. Quisenberry, Ligia Bejat Jan 1998

Solute And Bacterial Transport Through Partially-Saturated Intact Soil Blocks, Edmund Perfect, Mark S. Coyne, Michael C. Sukop, Gerald R. Haszler, Virgil L. Quisenberry, Ligia Bejat

KWRRI Research Reports

Steady-state transport of water, chloride and bacteria was measured through intact blocks of Maury and Cecil soils, under partially saturated conditions. Major objectives were to determine if transport occurs uniformly or via preferential flow paths, and if soil physical properties could be used to predict breakthrough. The blocks were instrumented with TDR probes and mounted on a vacuum chamber containing 100 cells that collected eflluent. After each experiment the blocks were sampled for soil physical properties. The fluxes showed no spatial autocorrelation and the eflluent variance was not statistically different between soils. Less than 3% of the influent bacteria appeared …


Spatial And Temporal Variability In Seepage Between A Contaminated Aquifer And Tributaries To The Ohio River, Alan E. Fryar, David L. Brown, David B. Wenner, Todd C. Rasmussen, Eric J. Wallin Jan 1998

Spatial And Temporal Variability In Seepage Between A Contaminated Aquifer And Tributaries To The Ohio River, Alan E. Fryar, David L. Brown, David B. Wenner, Todd C. Rasmussen, Eric J. Wallin

KWRRI Research Reports

Because interactions between ground water and tributaries may influence contaminant loading to rivers, we delineated seepage along Little Bayou and Bayou Creeks in McCracken County, Kentucky, during a two-year period. From the Paducah Gaseous Diffusion Plant, on the divide between the creeks, trichloroethene and technetium-99 plumes extend several km toward the Ohio River. Gaining conditions occur where the creeks are incised into coarse sediments in the river's flood plain. Such conditions were marked by upward hydraulic gradients within the bed; maximum specific discharge (q) > 0.24 m d-1; relatively narrow ranges of stream, piezometer, and bed temperatures; relatively cool …


Soil Moisture Gradients And Controls On A Southern Appalachian Hillslope From Drought Through Recharge, J. Alan Yeakley, W. T. Swank, L. W. Swift, G. M. Hornberger, H. H. Shugart Jan 1998

Soil Moisture Gradients And Controls On A Southern Appalachian Hillslope From Drought Through Recharge, J. Alan Yeakley, W. T. Swank, L. W. Swift, G. M. Hornberger, H. H. Shugart

Environmental Science and Management Faculty Publications and Presentations

Soil moisture gradients along hillslopes in humid watersheds, although indicated by vegetation gradients and by studies using models, have been difficult to confirm empirically. While soil properties and topographic features are the two general physio-graphic factors controlling soil moisture on hillslopes, studies have shown conflicting results regarding which factor is more important. The relative importance of topographic and soil property controls was examined in an upland forested watershed at the Coweeta Hydrologic Laboratory in the southern Appalachian mountains. Soil moisture was measured along a hillslope transect with a mesic-to-xeric forest vegetation gradient over a period spanning precipitation extremes. The hillslope …


A Methodology For Studying Denitrification By Recently Formed Sulfides, Bethany A. Bolles Jan 1998

A Methodology For Studying Denitrification By Recently Formed Sulfides, Bethany A. Bolles

Theses and Dissertations

Nitrate (N03) contamination due to anthropogenic sources is a serious and widespread health problem. In many groundwater systems, N03-can be reduced to a harmless gas, N2, through the bacterially mediated process of denitrification. During this process, bacteria gain energy by transferring electrons from an "electron donor" to nitrate, the "electron acceptor". It is typically believed that organic carbon is the most important electron donor in the denitrification process; however, increasing amounts of research suggest the importance of inorganic electron donors. The most extensive studies involving the reduction ofN03- by inorganic species have focused on pyrite (FeS2) and Fe(II). Few studies …


Phosphorus In The Landscape: Diffuse Sources To Surface Waters. Land And Water Resources Research And Development Corporation. Occasional Paper 16/98, Richard Davis, Anne Hamblin, E O'Loughlin, Nic Austin, R Banens, P Cornish, P Hairsin, M Mcculloch, Phil Moody, J Olley, B Prove, I Smalls, David Weaver Jan 1998

Phosphorus In The Landscape: Diffuse Sources To Surface Waters. Land And Water Resources Research And Development Corporation. Occasional Paper 16/98, Richard Davis, Anne Hamblin, E O'Loughlin, Nic Austin, R Banens, P Cornish, P Hairsin, M Mcculloch, Phil Moody, J Olley, B Prove, I Smalls, David Weaver

All other publications

The National Eutrophication Management Program (NEMP) and Environment Australia convened a workshop to develop a coherent overview of the sources and transport of diffuse phosphorus in Australian catchments based on the latest knowledge. The Land and Water Resources Research and Development Corporation (LWRRDC) and the Murray–Darling Basin Commission (MDBC) jointly fund NEMP. A select group of scientists attended the workshop and developed a coherent statement about phosphorus sources and transport in Australian catchments. The group did not extend this statement to include recommended management practices. This paper reports the findings from the workshop. State governments have developed algal and nutrient …


Identification Of Past Climate Variability Of The Eastern Pacific Ocean Using Both D13c And D18o Records In Corals From Clipperton Atoll (1994-1906), Lei Ren Jan 1998

Identification Of Past Climate Variability Of The Eastern Pacific Ocean Using Both D13c And D18o Records In Corals From Clipperton Atoll (1994-1906), Lei Ren

Geology Theses and Dissertations

The ENSO (El Nino and the Southern Oscillation) is a fundamental ocean-atmosphere phenomenon that dominates interannual global climate variability. Reconstructing past ENSO events is therefore important for documenting and understanding the past behavior of the global climate system and enabling us to predict future climate change. However, the present understanding of ENSO events has been mainly based on the instrumental record of Pacific climate which provides detailed data only for the past few decades. Recent studies have shown that the stable isotope record in coral skeletons can be used as a valuable indicator of paleoclimatic changes in tropical regions, and …


Geochronology And Geochemistry Of Basaltic Rocks In The Karasu Graben Around Kırıkhan (Hatay), S. Turkey, Osman Parlak, Ali̇can Kop, Ulvi̇ Can Ünlügenç, Cavi̇t Demi̇rkol Jan 1998

Geochronology And Geochemistry Of Basaltic Rocks In The Karasu Graben Around Kırıkhan (Hatay), S. Turkey, Osman Parlak, Ali̇can Kop, Ulvi̇ Can Ünlügenç, Cavi̇t Demi̇rkol

Turkish Journal of Earth Sciences

The study area, which is located in the middle sector of the Amanos mountains, covers the north of Kırıkhan (Hatay) in southern Turkey. Tectonostratigraphic rock units from Paleozoic to Cenozoic are exposed within this terrain, which is tectonically active as a result of continent-continent collision between Afro-Arabia and Eurasia. Young basaltic volcanism, located at the N-end of the Dead Sea transform fault in southern Turkey, crops out along the NE-SW trending structural lineaments within the Karasu valley (Hatay). K.Ar age determinations performed on the volcanic rocks give an age range from 0.4 Ma to 2.2 Ma that indicate Plio-Quaternary time …


Miocene Synvolcanic Alluvial Sedimentation In Lignite-Bearing Soma Basin, Western Turkey, Uğur İnci̇ Jan 1998

Miocene Synvolcanic Alluvial Sedimentation In Lignite-Bearing Soma Basin, Western Turkey, Uğur İnci̇

Turkish Journal of Earth Sciences

Calcalkaline volcanism and volcaniclastic deposition controlled considerable mode of late Miocene sedimentation and basinal development of the lignite-bearing Soma basin in western Turkey. The volcanism-induced Denis Formation, overlying the Soma Formation discordantly, is represented by two rock assemblages: 1) In the depositional axis of the basin, green, fine-grained sandstone dominated alluvial-lacustrine deposits and, 2) In the northern margin of te basin, syn-eruptive volcaniclastic apron deposits which are mainly composed of fine and coarse-grained volcaniclastic/pyroclastic rocks and lavas. The primary volcanic rocks surrounding probably low-relief volcanoes representing near-vent assemblage are composed mainly of andesitic, rhyolitic and basaltic lavas and pyroclastics. These …


Strain Analysis Of The Kapidagi Peninsula Shear Zone In The Ocaklargranitoid, Nw Turkey, Rahmi̇ Aksoy Jan 1998

Strain Analysis Of The Kapidagi Peninsula Shear Zone In The Ocaklargranitoid, Nw Turkey, Rahmi̇ Aksoy

Turkish Journal of Earth Sciences

The Kapidagi Peninsula shear zone is a W-to NW-trending, moderately to steeply dipping, sinistral strike-slip shear zone that runs almost parallel to the northern coast of the peninsula. It is a minimum of 28 km in length and extends from Rikoz Cape in the west to the north of Çakil village in the east. A quantitative strain analysis is presented for the shear zone evolved in the Ocaklar Granitoid by a syn-shear granitod intrusion. Deformed autoliths in the granitoids were used as strain markers. Long, intermediate and short axes of autoliths were measured in 66 subareas across the shear zone. …


Ree Chemistry Of Arid Zone Calcrete Profiles-A Case Study From The Thar Desert, India, D. Ramakrishnan, Krishna Chandra Tiwari Jan 1998

Ree Chemistry Of Arid Zone Calcrete Profiles-A Case Study From The Thar Desert, India, D. Ramakrishnan, Krishna Chandra Tiwari

Turkish Journal of Earth Sciences

Calcrete is the widely prevalent duricrust associated with the weathering profiles of the Thar desert. The studies on REE behaviour within different weathering horizons of calcrete profiles, have revealed distinct pattern of enrichment and depletion. Fractionation of REE as evidenced through La/Lu, La/Sm, Nd/Dy ratios and removal index, are attributed to pedogenic processes such as breakdown of micas, pyroxenes, amphiboles, feldspars; removal of elements as soluble complexes; selective fixation of elements in neoformed clay minerals like montmorillonite, illite and chlorite. Sesquioxides rich Bir horizon shows enrichment of REE. REE depletion in Palaeo- Bt horizons could be due to their removal …


Stable Isotopes And Sediments From Pickerel Lake, South Dakota, Usa: A 12ky Record Of Environmental Changes, Antje Schwalb, Walter E. Dean Jan 1998

Stable Isotopes And Sediments From Pickerel Lake, South Dakota, Usa: A 12ky Record Of Environmental Changes, Antje Schwalb, Walter E. Dean

United States Geological Survey: Staff Publications

Sedimentological parameters and stable O- and C-isotopic composition of marl and ostracode calcite selected from a 17.7 m long core from the 8 m deep center of Pickerel Lake, northeastern South Dakota, provide one of the longest (ca. 12ky) paleoenvironmental records from the northern Great Plains. The late Glacial to early Holocene climate in the northern Great Plains was characterized by changes from cold and wet to cold and dry, and back to cold and wet conditions. These climatic changes were controlled by fluctuations in the positions of the Laurentide ice sheet and the extent of glacial Lake Agassiz. We …


Evaluation Of The Acoustic Doppler Velocimeter (Adv) For Turbulence Measurements, George Voulgaris, John H. Trowbridge Jan 1998

Evaluation Of The Acoustic Doppler Velocimeter (Adv) For Turbulence Measurements, George Voulgaris, John H. Trowbridge

Faculty Publications

Accuracy of the acoustic Doppler velocimeter (ADV) is evaluated in this paper. Simultaneous measurements of open-channel flow were undertaken in a 17-m flume using an ADV and a laser Doppler velocimeter. Flow velocity records obtained by both instruments are used for estimating the true (‘‘ground truth’’) flow characteristics and the noise variances encountered during the experimental runs. The measured values are compared with estimates of the true flow characteristics and values of variance (^u92&, ^w92&) and covariance (^u9w9&) predicted by semiempirical models for open-channel flow. The analysis showed that the ADV sensor can measure mean velocity and Reynolds stress within …


Alkaline Rocks And Geodynamics, Bernard Bonin Jan 1998

Alkaline Rocks And Geodynamics, Bernard Bonin

Turkish Journal of Earth Sciences

Origin of A-type alkali feldspar granites is currently the subject of a world-wide debate. Contrasting hypotheses have been proposed, which range from an entirely crustal origin to an almost complete mantle derivation. A-type alkali feldspar granites belong to either unimodal granite (rhyolite)-dominated association, or bimodal gabbro (basalt)-granite (rhyolite) suite. It is argued that (i) the ultimate mantle origin of basic to intermediate rocks is beyond doubt, (ii) highly evolved felsic rocks may be produced by other processes besides crustal involvement through anatexis and (iii) large volumes of felsic rocks are a normal and direct consequence of extensive crystal fractionation processes. …


Oil And Gas Map Of The Evansville 30 X 60 Minute Quadrangle, Kentucky, Brandon C. Nuttall Jan 1998

Oil And Gas Map Of The Evansville 30 X 60 Minute Quadrangle, Kentucky, Brandon C. Nuttall

Map and Chart--KGS

No abstract provided.


Mineral And Fuel Resources Map Of Kentucky, Warren H. Anderson, Garland R. Dever Jr. Jan 1998

Mineral And Fuel Resources Map Of Kentucky, Warren H. Anderson, Garland R. Dever Jr.

Map and Chart--KGS

The production of minerals and fuels in Kentucky is a multibillion dollar industry. Historically, coal, oil, natural gas, limestone, sand and gravel, clay, fluorite, barite, lead, iron, phosphate, zinc, and brines have been produced in the State. These resources have greatly influenced the development of Kentucky by providing raw materials for the early settlers who settled the State and for current industrial and economic development. Electrical power for homes, businesses, and factories; materials for constructing houses, buildings, automobiles, and roads; and products we consume in everyday life come from the earth's mineral and fuel resources.


Impact Of Topographic And Data Resolution On Hydrologic And Nonpoint-Source Pollution Modeling In A Karst Terrane, Alex W. Fogle Jan 1998

Impact Of Topographic And Data Resolution On Hydrologic And Nonpoint-Source Pollution Modeling In A Karst Terrane, Alex W. Fogle

Report of Investigations--KGS

To prevent or reduce the contamination of ground water from agricultural sources, Best Management Practices (BMP’s) such as land-use changes, modifications to control surface runoff, various tillage methods, variations in rates and kinds of chemical applications, and handling procedures for chemicals are being employed and analyzed for effectiveness. The effectiveness of a BMP is often estimated before implementation by evaluating the BMP through the use of computer simulation models. The interactions between surface water and ground water that are unique to karst terranes are not incorporated into the frequently used predictive models. The purpose of this study was to document …


A Geochemical Study Of Marine Sediments From The Mac. Robertson Shelf, East Antarctica: Initial Results And Palaeoenvironmental Implications, Peter N. Sedwick, P. T. Harris, L. G. Robertson, G. M. Mcmurtry, M. D. Cremer, P. Robinson Jan 1998

A Geochemical Study Of Marine Sediments From The Mac. Robertson Shelf, East Antarctica: Initial Results And Palaeoenvironmental Implications, Peter N. Sedwick, P. T. Harris, L. G. Robertson, G. M. Mcmurtry, M. D. Cremer, P. Robinson

OES Faculty Publications

Sediments from the Antarctic continental margin may provide detailed palaeoenvironmental records for Antarctic shelf waters during the late Quaternary. Here we present results from a palaeoenvironmental study of two sediment cores recovered from the continental shelf off Mac. Robertson Land, East Antarctica. These gravity cores were collected approximately 90 km apart from locations on the inner and outer shelf. Both cores are apparently undisturbed sequences of diatom ooze mixed with fine, quartz-rich sand. Core stratigraphies have been established from radiocarbon analyses of bulk organic carbon. Down-core geochemical determinations include the lithogenic components Al and Fe, biogenic components opal and organic …


South Central Nebraska Geology Field Trip Conservation And Survey Division-Ianr-Unl & Nebraska Well Drillers Association, Conservation Survey Division Jan 1998

South Central Nebraska Geology Field Trip Conservation And Survey Division-Ianr-Unl & Nebraska Well Drillers Association, Conservation Survey Division

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Estimation Of Suspended Sediment Concentration In Water Using Integrated Surface Reflectance, Mahtab A. Lodhi, Donald C. Rundquist, Luoheng Han, Mark S. Kuzila Jan 1998

Estimation Of Suspended Sediment Concentration In Water Using Integrated Surface Reflectance, Mahtab A. Lodhi, Donald C. Rundquist, Luoheng Han, Mark S. Kuzila

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Nebraska Oil And Gas Production And Value For 1996 And 1997, R. R. Burchett, W. H. Sydow Jan 1998

Nebraska Oil And Gas Production And Value For 1996 And 1997, R. R. Burchett, W. H. Sydow

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Oil And Gas Facts For Nebraska, R. R. Burchett Jan 1998

Oil And Gas Facts For Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Dodge County Test Hole Logs, Frank A. Smith, Raymond R. Burchett Jan 1998

Dodge County Test Hole Logs, Frank A. Smith, Raymond R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Harlan County Test Hole Logs, Raymond R. Burchett Jan 1998

Harlan County Test Hole Logs, Raymond R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Twin Platte Natural Resources District Groundwater Quality Study, D. C. Gosselin, L. Howard, J. Goeke Jan 1998

Twin Platte Natural Resources District Groundwater Quality Study, D. C. Gosselin, L. Howard, J. Goeke

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Heat And Salt Changes On The Continental Shelf West Of The Antarctic Peninsula Between January 1993 And January 1994, John M. Klinck Jan 1998

Heat And Salt Changes On The Continental Shelf West Of The Antarctic Peninsula Between January 1993 And January 1994, John M. Klinck

CCPO Publications

Hydrographic measurements from four cruises between January 1993 and January 1994 over the continental shelf west of the Antarctic Peninsula allow analysis of seasonal changes in heat and salt content of this region. Changes above the permanent pycnocline (about 150 m) follow a seasonal pattern of cooling and increasing in salt from summer to winter and warming and freshening from winter to summer. These near-surface changes expressed as net heating or salting rate, were above 80 W m(-2) and 4 mg salt m(-2) s(-1). The year to year difference was small compared to the seasonal changes. There was no seasonal …


Crevasse Patterns And The Strain-Rate Tensor: A High-Resolution Comparison, Joel T. Harper, Neil Humphrey, W. Tad Pfeffer Jan 1998

Crevasse Patterns And The Strain-Rate Tensor: A High-Resolution Comparison, Joel T. Harper, Neil Humphrey, W. Tad Pfeffer

Geosciences Faculty Publications

Values of the strain-rate tensor represented at a 20 m length scale are found to explain the pattern and orientation of crevasses in a 0.13 km2 reach of Worthington Glacier, Alaska, U.S.A. The flow field of the reach is constructed from surveyed displacements of 110 markers spaced 20-30 m apart. A velocity gradient method is then used to calculate values of the principal strain-rate axes at the nodes of a 20 m x 20 m orthogonal grid. Crevasses in the study reach are of two types, splaying and transverse, and are everywhere normal to the trajectories of greatest (most …


Paleosols As Holocene Proxy Climate Indicators, Mclean County, North Dakota, Deborah L. Beck Jan 1998

Paleosols As Holocene Proxy Climate Indicators, Mclean County, North Dakota, Deborah L. Beck

Theses and Dissertations

An exposure with 15 buried A-horizons near Douglas Creek, Lake Sakakawea, central North Dakota, has provided an excellent opportunity for paleoclimate reconstruction. Analyses included texture, stable carbon, radiocarbon, pollen, and phytoliths. The variations in these properties between individual soil horizons served to reconstruct the former environments of each soil horizon.

The paleosols were developed in a sequence of deposits in a mile-long tributary to the Missouri River. The soils are in a shallow valley fill exposed by wave action along the north shore of Lake Sakakawea. The 1996 exposure was up to 4m high and 51.5m wide. There were up …


Quartzite Fabric Transition In A Cordilleran Metamorphic Core Complex, Allen J. Mcgrew, Martin Casey Jan 1998

Quartzite Fabric Transition In A Cordilleran Metamorphic Core Complex, Allen J. Mcgrew, Martin Casey

Department of Earth, Environment and Sustainability Faculty Publications

Photomicrographs 143A-143F record fabric variations in quartzite with increasing structural depth in a > 1 km thick, amphibolite-facies, normal-sense shear zone in the East Humboldt metamorphic core complex, Nevada (Figure 143.1). This shear zone and the overlying detachment system unroofed an infrastructure of high-grade, migmatitic gneiss during Oligocene to early Miocene extension (Dallmeyer and others, 1986; Wright and Snoke, 1993; McGrew and Snee, 1994). Thermobarometric constraints from near the base of the mylonitic zone record deformation conditions of 550°- 620°C and 300-400 MPa (Hurlow and others, 1991). Sample WBC6 (l43A and 143B) characterizes the mylonitic zone, whereas sample 8706-1 (143C and …