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Articles 53911 - 53940 of 59385
Full-Text Articles in Entire DC Network
The 1987 Nonpoint Source Pollution Amendments And State Progress Under The New Program, John H. Davidson
The 1987 Nonpoint Source Pollution Amendments And State Progress Under The New Program, John H. Davidson
Water Quality Control: Integrating Beneficial Use and Environmental Protection (Summer Conference, June 1-3)
143 pages.
Contains 4 pages of references.
Antidegradation And Nonpoint Source Pollution In The West, H. Michael Anderson
Antidegradation And Nonpoint Source Pollution In The West, H. Michael Anderson
Water Quality Control: Integrating Beneficial Use and Environmental Protection (Summer Conference, June 1-3)
31 pages.
Contains references.
Soil Erosion, Agrichemicals And Water Quality: A Need For A New Conservation Ethic?, Christine Olsenius
Soil Erosion, Agrichemicals And Water Quality: A Need For A New Conservation Ethic?, Christine Olsenius
Water Quality Control: Integrating Beneficial Use and Environmental Protection (Summer Conference, June 1-3)
24 pages.
Contains references.
The San Joaquin–Sacramento Delta, David R. Beringer
The San Joaquin–Sacramento Delta, David R. Beringer
Water Quality Control: Integrating Beneficial Use and Environmental Protection (Summer Conference, June 1-3)
20 pages.
Contains 2 pages of references.
Public Land Livestock Grazing, Water Quality And Riparian Ecosystems: The Evolving Legal And Technical Context, Richard H. Braun
Public Land Livestock Grazing, Water Quality And Riparian Ecosystems: The Evolving Legal And Technical Context, Richard H. Braun
Water Quality Control: Integrating Beneficial Use and Environmental Protection (Summer Conference, June 1-3)
8 pages.
Contains 1 page of references.
Legal Issues: San Francisco Bay, Sacramento-San Joaquin River Delta And Estuary, Stuart L. Somach
Legal Issues: San Francisco Bay, Sacramento-San Joaquin River Delta And Estuary, Stuart L. Somach
Water Quality Control: Integrating Beneficial Use and Environmental Protection (Summer Conference, June 1-3)
48 pages.
Contains footnotes.
Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale
Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale
Arkansas Water Resources Center Technical Reports
In Arkansas, approximately 1 Tg of poultry (Gallus gallus domesticus) manure and litter is produced annually. These waste products are commonly applied to pastures as a soil amendment or fertilizer, but excessive application rates and poor management practices could result in nutrient contamination of ground and surface water. The purpose of this study was to: (1) assess the nutrient concentrations in poultry manure and (2) evaluate the nitrogen loss from land-applied poultry litter and manure due to ammonia volatilization and denitrification. Analyses for total Kjeldahl nitrogen (TKN), inorganic nitrogen (Ni), phosphorus (P), and potassium (K) were compared in 12 wet …
Development Of A Combined Quantity And Quality Model For Optimal Management Of Unsteady Groundwater Flow Fields, R. C. Peralta, J. Solaimanian, C. L. Griffis
Development Of A Combined Quantity And Quality Model For Optimal Management Of Unsteady Groundwater Flow Fields, R. C. Peralta, J. Solaimanian, C. L. Griffis
Arkansas Water Resources Center Technical Reports
Presented are alternative techniques for including conservative solute transport within computer models for optimizing groundwater extraction rates. Unsteady two-dimensional flow and dispersed conservative solute transport are assumed. Comparisons are made of the practicality of including modified forms of implicit and explicit finite difference solute transport equations within optimization models. These equations can be calibrated and subsequently used within a MODCON procedure. The MODCON modelling procedure consists of an integrated series of five optimization or simulation modules. The procedure is applicable for either an entire aquifer system or for a subsystem of a larger system. The first module, A, computes physically …
Qualitative And Quantitative Aquatic Algal Data Compilation To Determine Macrotrends - Iv, Richard L. Meyer
Qualitative And Quantitative Aquatic Algal Data Compilation To Determine Macrotrends - Iv, Richard L. Meyer
Arkansas Water Resources Center Technical Reports
A data base of the algae of Arkansas ecoregions has been estabblished by the use of a relational data base management system (dBase III plus). The system was chosen to be readily available for a variety of microcomputers using MS- and PC-DOS. The data base contains taxonomic fields from division through variety, synonymy, authors, initial description, date, and definitive descriptive source. The data are cross-referenced by ecoregion, Round's community and subcommunity designations. The data base contains greater than 1,500 taxonomic records in all divisions and classes of freshwater algae. The data are sortable by any of the included parameters. The …
Patterns Of Sulfur Deposition In The Wood Of Pinus Echinatia Mill. From The Cumberland Plateau In Kentucky, Darrell Ray
Patterns Of Sulfur Deposition In The Wood Of Pinus Echinatia Mill. From The Cumberland Plateau In Kentucky, Darrell Ray
Masters Theses & Specialist Projects
Air pollution and acid precipitation have long had an influence on plant and animal life. In this study, the level of sulfur in the stem tissue of Pinus echinata Mill. was measured in trees from various sites along the western edge of the Cumberland Plateau to determine the presence and pattern of sulfur deposition in this species. Overall, a 40.28% increase in sulfur levels was observed from four sites along the plateau with levels increasing from 0.072 mgS/gdwt in the 1962-66 growth increment to 0.101 mg in the 1982-86 increment. According to a computer generated analysis of variance, the differences …
Long-Term Reconstruction And Analysis Of White River Streamflow, M. K. Cleaveland, D. W. Stahle, J. G. Hehr
Long-Term Reconstruction And Analysis Of White River Streamflow, M. K. Cleaveland, D. W. Stahle, J. G. Hehr
Arkansas Water Resources Center Technical Reports
A 281-year reconstruction of White River annual runoff at Clarendon, Arkansas, was developed from a regional average of nine Oklahoma, Missouri, and Arkansas tree-ring chronologies (six post oak, Quercus stellata, and three baldcypress, Taxodium distichum). Inhomogeneity of the gaged series was detected with both double mass analysis (using state average total annual Arkansas precipitation) and regression (using the regional tree-ring average). Simple regression calibrated the homogeneous runoff data with the average ring width data from 1930 to 1980. Comparing the reconstruction with independent data verified the regression model. Variance of the reconstruction increases significantly during the 20th century, a change …
Electrical Resistivity As An Approach To Evaluating Brine Contamination Of Groundwater In The Walker Oil Field, Ottawa County, Michigan, Janet A. Koehler
Electrical Resistivity As An Approach To Evaluating Brine Contamination Of Groundwater In The Walker Oil Field, Ottawa County, Michigan, Janet A. Koehler
Masters Theses
Surface electrical resistivity successfully defined brine contamination within a glacial drift aquifer in western Michigan. The study site is in a residential area of eastern Ottawa County, in the Walker Oil Field. A Schlumberger array with a maximum current electrode separation (AB/2) of 316 meters (1037 feet) was used. It was possible to detect geoelectric layers to about 30 meters (100 feet) below ground level, with the maximum current penetration of about 1/10 (AB/2). On occasion, thick surficial clay precluded detecting deeper geoelectric layers. Through use of the INVERS computer program, fifty vertical electrical soundings were interpreted and correlated with …
Fission-Track Geochronology And Geothermometry Of Late Cretaceous-Early Tertiary Epizonal Plutons, In And Adjacent To The Lombard Thrust Fault, Southwestern Montana, Jean Talanda
Masters Theses
Thrusting occurred in the central portion of the central Montana salient where the timing of movements is somewhat obscured by the multiple deformations from Archean time to the present. The relationship of this thrusting to the associated plutons has not been established in every case. Fission-track geochronology was employed in dating several plutons associated with the Lombard thrust fault, consequently, defining a time range in which movement along the thrust occured.
Seven plutons with known structural relationships to the Lombard thrust have ages which suggest that movement along the fault occurred 73.2 +/- 6.7 Ma. Fission-track length distributions suggest that …
A Field Trip Guide To The Sue Point Fossil Coral Reef San Salvador Island, Bahamas, Brian White
A Field Trip Guide To The Sue Point Fossil Coral Reef San Salvador Island, Bahamas, Brian White
Geosciences: Faculty Publications
See other Smith authored Field Trip Guides of Gerace Research Centre.
Update On Ridge-Tillage In Kentucky, David C. Ditsch, Monroe Rasnake
Update On Ridge-Tillage In Kentucky, David C. Ditsch, Monroe Rasnake
Soil Science News and Views
Grain crop producers in Kentucky are constantly evaluating various tillage systems that will best fit their particular cropping environment. One such tillage system that has shown some promise primarily in the mid-west is a system referred to as ridge-tillage. Ridge-till is basically a system by which a grain producer plants his crop on an elevated row that is maintained each year during cultivation for week control. The same ridge is re-used year after year thereby developing a controlled traffic pattern. Since the cultivation procedure is also recommended for maintaining the ridge, many ridge-till farmers have reduced their herbicide cost by …
Effect Of Wet Tropospheric Path Delays On Estimation Of Geodetic Baselines In The Gulf Of California Using The Global Positioning System, David M. Tralli, Timothy H. Dixon, Scott A. Stephens
Effect Of Wet Tropospheric Path Delays On Estimation Of Geodetic Baselines In The Gulf Of California Using The Global Positioning System, David M. Tralli, Timothy H. Dixon, Scott A. Stephens
School of Geosciences Faculty and Staff Publications
Geodetic baseline measurements using the Global Positioning System (GPS) were acquired in the Gulf of California between Loreto and Cabo San Lucas in Baja California and Mazatlan on the mainland of Mexico. Tropospheric water vapor content was high during the experiment, typically yielding wet path delays in excess of 20 cm at zenith. Surface meteorological (SM) and water vapor radiometer (WVR) measurements were recorded at each site, providing independent means of calibrating the GPS signal for the wet tropospheric path delay. Residual wet delays at zenith are estimated as constants and also as first-order exponentially correlated stochastic processes. In addition, …
An Investigation Of A Soil Gas Sampling Technique And Its Applicability For Detecting Gaseous Pce And Tca Over An Unconfined Granular Aquifer, Timothy J. Mayotte
An Investigation Of A Soil Gas Sampling Technique And Its Applicability For Detecting Gaseous Pce And Tca Over An Unconfined Granular Aquifer, Timothy J. Mayotte
Masters Theses
A soil gas sampling and analytical technique was investigated to evaluate its ability and versatility for detecting chlorinated hydrocarbons in unconfined aquifers. The technique was used successfully to delineate plumes of perchloroethene (PCE), and 1,1,1-trichloroethane (TCA) contamination present in the vadose zone, and at the water table of an unconfined sand and gravel aquifer. Soil gas samples were obtained by concentrating PCE and TCA vapors diffusing from these sources onto a sorbent material. The samples were analyzed by gas chromatography. The data from the analysis of these samples were used to provide an initial estimate of the source areas, and …
The Occurrence Of Fish Remains In Modern Lake Systems : A Test Of The Stratified-Lake Mode, Douglas R. Britton
The Occurrence Of Fish Remains In Modern Lake Systems : A Test Of The Stratified-Lake Mode, Douglas R. Britton
Loma Linda University Electronic Theses, Dissertations & Projects
Theories regarding the taphonomy of fishes in lacustrine environments have traditionally relied on an anoxic water column to explain the excellent preservation. This concept has never been directly tested in modern lacustrine environments that are thought to be analogous to the lacustrine environments predicted by the Stratified-lake Model. This research tested that model by searching for fish remains in 38 collected bottom samples of six modern lacustrine analogues, including Fayetteville Green Lake, New York. The bottom sediments of a warm, holomictic, shallow, and saline lake (Salton Sea, California) were also examined. Although laminated sediments were found in all of the …
The Concept Of Prime Agricultural Land: A Western Australian Perspective, Vivian T. Read
The Concept Of Prime Agricultural Land: A Western Australian Perspective, Vivian T. Read
Resource management technical reports
In the past, resource planning by Government authorities in Western Australia has been concentrated in urban areas. The rural areas were referred to as non-urban and planning outside of country townsites was confined to special rural zones. These zones were determined by the State authority (Town Planning Department) and were intended to limit the extent of farm fragmentation so as to control servicing costs and possible conflict.
The new State Planning Commission is expected soon to introduce the requirement of rural planning strategies for Local Government Areas where demand for land subdivision is high. The strategies will be based on …
A Guide To The Practical Use Of Aerial Color-Infrared Photography In Agriculture, Donald C. Rundquist, Scott A. Samson
A Guide To The Practical Use Of Aerial Color-Infrared Photography In Agriculture, Donald C. Rundquist, Scott A. Samson
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Estimated Use Of Water In Nebraska, 1985, Eugene K. Steele Jr.
Estimated Use Of Water In Nebraska, 1985, Eugene K. Steele Jr.
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Rimforest Landslides, San Bernardino Mountains, Southern California, David L. Hanson
Rimforest Landslides, San Bernardino Mountains, Southern California, David L. Hanson
Loma Linda University Electronic Theses, Dissertations & Projects
The highly visible erosional scars near the crest of the San Bernardino Mountains just east of Strawberry Peak near the community of Rimforest are active landslides. From at least the 1920's to 1988 the primary activity has been mass wasting by rockfall in highly fractured quartz monzonite. Tension cracks in the adjacent area indicate that active landsliding may be spreading. Landsliding in this area had its origin most likely with the uplift of the San Bernardino Mountains and has continued with periods of active movement associated with heavy precipitation and seismic activity separated by long periods of dormancy. The geomorphology …
Geochemical Stratigraphy Of The Dooley Rhyolite Breccia And Tertiary Basalts In The Dooley Mountain Quadrangle, Oregon, David Neale Whitson
Geochemical Stratigraphy Of The Dooley Rhyolite Breccia And Tertiary Basalts In The Dooley Mountain Quadrangle, Oregon, David Neale Whitson
Dissertations and Theses
The Dooley Rhyolite Breccia in northeast Oregon was erupted between 12 and 16 million years ago, from central vents and linear feeder dikes within the Dooley Mountain quadrangle. The peraluminous, high-silica rhyolites of the formation were erupted over an irregular highland of eroded pre-Tertiary metamorphic rocks locally overlain by intracanyon, Eocene Clarno-type basalt flow(s). The Dooley Rhyolite Braccia is exposed in a tectonically disrupted, north-south trending graben across the Elkhorn Range. The formation is variable in thickness with maximum thickness exceeding 660 meters in the south and 600 meters in the north half of the quadrangle. Volumetrically the formation is …
A Field Perspective On Groundwater Contamination, John A. Cherry
A Field Perspective On Groundwater Contamination, John A. Cherry
Maine Collection
A Field Perspective on Groundwater Contamination
Geological Society of Maine Distinguished Lecturer John Cherry, University of Waterloo, Ontario, sponsored by the Department of Geosciences, University of Southern Maine, 19th May 1988.
Contents: Lecture 1 : Contaminant Migration Processes Illustrated by Field Experiments / Lecture 2 : Behavior of Dense Non-Aqueous Phase Liquids, Illustrated by Lab Experiments and Conceptual Examples / Lecture 3 : Field Case Histories on Groundwater Contamination / Lecture 4 : Hydrogeological Concepts and Criteria for Waste Disposal / Waterloo Center for Groundwater Research Publications List
The Mechanism Of Intrusion Of The Inyo Dike, Long Valley Caldera, California, Ze'ev Reches, Jonathan H. Fink
The Mechanism Of Intrusion Of The Inyo Dike, Long Valley Caldera, California, Ze'ev Reches, Jonathan H. Fink
Geology Faculty Publications and Presentations
We analyze the intrusion of the 11-km-long lnyo Dike at the margins of Long Valley caldera, eastern California. The dike trends N07°W and is divided into at least three segments which are rotated by as much as 25° with respect to the main trend. The dike seems affected primarily by the regional stress field of right-lateral shear of the western United States and by the local thermal conditions of the crust; the dike seems unaffected by the preexisting caldera margins and Sierra-Nevada frontal fault system. The high heat flow in Long Valley caldera implies that crustal rocks below 3-4.5 km …
Common Characteristics Of Paired Volcanoes In Northern Central America, S. P. Halsort, William I. Rose
Common Characteristics Of Paired Volcanoes In Northern Central America, S. P. Halsort, William I. Rose
Department of Geological and Mining Engineering and Sciences Publications
Four pairs of active volcanoes along the northern Central American volcanic front have erupted basalt-andesite magmas that show consistent intrapair behavioral and compositional differences. These differences are found in records of volcanic activity and complete major and minor element data on over 200 samples. From northwest to southeast along the volcanic front the four volcano pairs are Cerro Quemado-Santa María, Tolimán-Atitlán, Acatenango-Fuego, and Santa Ana-Izalco. The volcano pair relations help explain compositional differences, apart from those reflecting variation in crustal thickness of about 15 km along the volcanic front, providing insight into across-arc variations and closely spaced subvolcanic plumbing systems. …
Direct Rate Measurements Of Eruption Plumes At Augustine Volcano: A Problem Of Scaling And Uncontrolled Variables, William I. Rose, Grant Heiken, Kenneth Wohletz, Dean Eppler, Sumner Barr, Theresa Miller, Raymond L. Chuan, R. B. Symonds
Direct Rate Measurements Of Eruption Plumes At Augustine Volcano: A Problem Of Scaling And Uncontrolled Variables, William I. Rose, Grant Heiken, Kenneth Wohletz, Dean Eppler, Sumner Barr, Theresa Miller, Raymond L. Chuan, R. B. Symonds
Department of Geological and Mining Engineering and Sciences Publications
The March–April 1986 eruption of Augustine Volcano, Alaska, provided an opportunity to directly measure the flux of gas, aerosol, and ash particles during explosive eruption. Most previous direct measurements of volcanic emission rates are on plumes from fuming volcanoes or on very small eruption clouds. Direct measurements during explosive activity are needed to understand the scale relationships between passive degassing or small eruption plumes and highly explosive events. Conditions on April 3, 1986 were ideal: high winds, clear visibility, moderate activity. Three measurements were made: 1) an airborne correlation spectrometer (Cospec) provided mass flux rates of SO2; 2) …
Geology And Petrogenesis Of Ash-Flow Tuffs And Rhyolitic Lavas Associated With The Gila Cliff Dwellings Basin-Bursum Calder Complex, Southwestern New Mexico, Sheila June Seaman
Geology And Petrogenesis Of Ash-Flow Tuffs And Rhyolitic Lavas Associated With The Gila Cliff Dwellings Basin-Bursum Calder Complex, Southwestern New Mexico, Sheila June Seaman
Earth and Planetary Sciences ETDs
The Mogollon-Datil volcanic field of southwestern New Mexico was the site of extensive mid-Tertiary felsic volcanism. The Bursum caldera-Gila Cliff Dwellings basin is a volcanic complex in which stratigraphic and compositional relationships between eruptive units are controversial. Uncertainties associated with the complex include the relative ages of the two overlapping structures, the caldera of origin of ash-flow tuff which fills the Gila Cliff Dwellings basin, and the reconciliation of stratigraphic and chemical relations between volcanic units. A stratigraphic, structural, paleomagnetic, and petrologic study of six ash-flow tuff and lava units has contributed data to several problems concerning the geologic history …
Effect Of Crop Rotation On Corn And Soybean Yields, James H. Herbek, Lloyd W. Murdock, T. Gray
Effect Of Crop Rotation On Corn And Soybean Yields, James H. Herbek, Lloyd W. Murdock, T. Gray
Soil Science News and Views
Yield of both corn and soybeans has been shown to increase when grown in a rotation as compared to continuous cropping of either of the two crops. These yield improvements are commonly associated with fewer disease, insect and weed problems; better soil tilth; and in the case of corn, a nitrogen contribution from the preceding soybean crop. One or a combination of these factors are believed to have an effect. In the past few decades the yield benefits of rotations were often overlooked as fertilizers and pesticides were used as a substitute for crop rotation. However, research has shown that …
Quaternary Geology And Tectonic Geomorphology Of The Pocatello Valley Area, Idaho-Utah, John D. Garr
Quaternary Geology And Tectonic Geomorphology Of The Pocatello Valley Area, Idaho-Utah, John D. Garr
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Pocatello Valley in southeastern Idaho and northern Utah is a structural and topographic basin bounded on all sides by mountains composed of Paleozoic platform carbonates and elastics. In the late Pleistocene it contained pluvial Lake Utaho, which, prior to 1981, was considered to have been an arm of Lake Bonneville. This study corroborates the finding of Currey (1981) that the two lakes were separate.
The Quaternary deposits examined in this study are divided into two broad groups: those that were deposited prior to the last pluvial lake cycle, and those that were deposited during and after the pluvial lake maximum, …