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Articles 16891 - 16920 of 17789
Full-Text Articles in Entire DC Network
Threshold Friction Velocities And Rupture Moduli For Crusted Desert Soils For The Input Of Soil Particles Into The Air, Dale A. Gillette, John Adams, Daniel R. Muhs, Rolf Kihl
Threshold Friction Velocities And Rupture Moduli For Crusted Desert Soils For The Input Of Soil Particles Into The Air, Dale A. Gillette, John Adams, Daniel R. Muhs, Rolf Kihl
United States Geological Survey: Staff Publications
Desert soils having clay crusts, mostly from the Mojave Desert, were tested for threshold friction velocity (the friction velocity at which soil erosion begins) with an open-bottomed wind tunnel. The soils were also tested for content of clay, water-soluble material, calcium carbonate, organic material, mineralogy of clay and of salts, soil moisture, modulus of rupture, and crust thickness. If no loose material existed on the soil surface, crusts having modulus of rupture greater than 0.7 bar and crust thickness of 0.7 cm to 0.3 cm were effective in protecting against wind erosion. Disturbed clay crusts having modulus of rupture before …
The Voluntary Water Quality Monitoring Program : 1982 Project Report, Barbara Welch, Judy Potvin, Mary Ellen Dennis
The Voluntary Water Quality Monitoring Program : 1982 Project Report, Barbara Welch, Judy Potvin, Mary Ellen Dennis
Maine Collection
The Voluntary Water Quality Monitoring Program : 1982 Project Report
by Barbara Welch, Judy Potvin & Mary Ellen Dennis
Division of Environmental Evaluation and Lake Studies, Maine Department of Environmental Protection, Augusta, Maine 1982.
Contents: Understanding Maine's Lakes and Ponds / Acknowledgement / Temperature / Dissolved Oxygen / Other Measures of Lake Water Quality / Nutrients / Algae and Chlorophyll a / Transparency / Morphometry / Sampling / Protection / Classification / Answers to Most Frequently Asked Questions / Glossary of Terms / Appendix A : Maximum, Minimum, and Mean Values / Appendix B : Phosphate Content of Common Cleansers …
Effect Of Herbicides On Performance Of Aerobic Dairy Lagoons, John D. Bottom, Joseph L. Taraba
Effect Of Herbicides On Performance Of Aerobic Dairy Lagoons, John D. Bottom, Joseph L. Taraba
Biosystems and Agricultural Engineering Faculty Publications
The herbicides glyphosate, bromacil, and dalapon were assessed for their affect on the oxygen uptake of microorganisms from an aerated dairy lagoon at 20 °C. The maximum recommended addition of herbicide active ingerdient to a lagoon is: glyphosate (isopropyl amino salt)—0.42 mg/L; bromacil—3.70 mg/L; and dalapon (85.8 percent Na salt and 14.2 percent Mg salt)—1.95 mg/L. In addition, microorganism isolates from the aerobic dairy lagoon were incubated under aerobic and anerobic conditions at room temperature to assess the effects of the herbicides. Under aerobic incubation, it was found that neither herbicide type nor herbicide concentration affected isolate growth. Under anaerobic …
1. Phosphorus Sources Trials 2. Miscellaneous Trials, J W. Bowden, R J. Lunt, M J. Baker
1. Phosphorus Sources Trials 2. Miscellaneous Trials, J W. Bowden, R J. Lunt, M J. Baker
Experimental Summaries - Plant Research
Sources of phosphorus trials - 1982 results. Pasture Trials, 76MT10, 77MT1, 77MT2, 76BU1, 77EI. Cropping Trials, 76WH14, 76WH10, 76WH9, 76N4, 76LG6, 80BA6. Trials not assessed in 1982, 77WH2 Pasture phase. Miscellaneous trials. Long term trials, 66M30, 65Al, 65A1, 65C5, 69WH15, 75LG26, 81N044, 78BA7. 1982 Trials, 82N04, 82BA2, 82N02, 82N05, 82WH2, 81N044.
Stratigraphy Of A Pennsylvanian Deltaic Sequence In Russellville, Arkansas, Christopher F. Moyer, Ken Fritsche
Stratigraphy Of A Pennsylvanian Deltaic Sequence In Russellville, Arkansas, Christopher F. Moyer, Ken Fritsche
Journal of the Arkansas Academy of Science
No abstract provided.
Glacial Deposits, Vol. 10, 1981-1982, Department Of Geography-Geology
Glacial Deposits, Vol. 10, 1981-1982, Department Of Geography-Geology
Glacial Deposits
Newsletter of the Department of Geography-Geology
Grain Legume Agronomy Programme., G. H. Walton
Grain Legume Agronomy Programme., G. H. Walton
Experimental Summaries - Plant Research
Lupin agronomy, Series l - Growth factor interactions. 82GE18, 82GE19, 82N038, 82N18, 82MA13. Lupin agronomy, Series 2 - Harvest index response to density 82GE20, 82M24. Lupin agronomy, nutrition, 82GE21, 82MA14, 82M017. Erregulla lupin rotation plots, 81M027, 81M029, 81M030. Grain legumes for wheatbelt rotations, 81GE6,81TS3, 81ME3, 81M05, 81MO14. Grain legume species trials, 81E30, 82NA31, 82JE23, 82E26, 82LG28. Low rainfall, medium soils pH 5.5 to 7.0, 82ME41, 82ES35, 82ES36, 82TS25, 82ME39. Sites that failed, 82GE23, 82ME40, 82JE18. Field pea agronomy, 82LG27, 82LG26. Oat/lupin mixtures for grain feed 82Bu9, 82Bu10, 82AL34. Oat/pea mixtures for hay, 82PE21, 82KA37. Fababean nodulation, 82MD16, 82MN25.
The Fayum Primate Forest Revisited, Thomas M. Bown, Mary Kraus, Scott Wing, John Fleagle, Bruce H. Tiffney, Elwyn Simons, Carl F. Vondra
The Fayum Primate Forest Revisited, Thomas M. Bown, Mary Kraus, Scott Wing, John Fleagle, Bruce H. Tiffney, Elwyn Simons, Carl F. Vondra
United States Geological Survey: Staff Publications
In Oligocene times, the Fayum area of northern Egypt was a subtropical to tropical lowland coastal plain with damp soils and seasonal rainfall that supported an abundance and variety of vegetation, including lianes (large vines), tall trees, and possibly mangroves, and a large and varied vertebrate fauna. The Oligocene marine strandline was close by and principal Jebel Qatrani Formation streams were probably brackish several kilometers inland due to tidal incursions. Sediments of the Jebel Qatrani Formation were deposited by several large meandering streams, associated with minor but sometimes extensive flood basin ponds. These rocks provide no evidence for the former …
Analysis Of Petroleum Source Rocks Of The Bakken Formation (Devonian And Mississippian) In North Dakota, Rick L. Webster
Analysis Of Petroleum Source Rocks Of The Bakken Formation (Devonian And Mississippian) In North Dakota, Rick L. Webster
Theses and Dissertations
The Bakken Formation of North Dakota consists of upper and lower, black, organic-rich shales separated by a calcareous siltstone middle member. The formation is a relatively thin unit (maximum thickness of 145 feet) with the lower shale .attaining a maximum thickness of 50 feet and the upper shale a maximum thickness of 23 feet. The shales are hard, siliceous, pyritic, fissile, and noncalcareous. They contain abundant conodonts and tasmanites and have planar laminations accented by pyrite. The upper and lower shales were apparently deposited in an offshore, marine, anoxic environment where anoxic conditions may have been caused by silling of …
Observations On The Biology Of Cave Planarians Of The United States, Jerry H. Carpenter
Observations On The Biology Of Cave Planarians Of The United States, Jerry H. Carpenter
International Journal of Speleology
Observations are made on the biology of several species of cave planarians (mostly of the family Kenkiidae) collected alive from over 50 caves in 14 states. Most of these species were maintained in laboratory cultures at 12°C±3°C. Food eaten was extremely variable. Functions of the anterior adhesive organ included food capture, locomotion, defence against predators, and probably chemoreception, mechanoreception, and as a holdfast in strong currents. Predators probably consist of fishes, crayfishes, and salamanders. Sporozoan and ciliated parasites were found occasionally. Cocoons were found in winter, spring, and summer; they hatched in about 3 months and contained 2 to 17 …
Paramexiweckelia, A New Genus Of Subterranean Amphipod Crustacean (Hadziidae) From Northern Mexico, John R. Holsinger
Paramexiweckelia, A New Genus Of Subterranean Amphipod Crustacean (Hadziidae) From Northern Mexico, John R. Holsinger
International Journal of Speleology
Paramexiweckelia, new genus, is described from a groundwater outlet in Cohauila, Mexico. The type-species, by monotypy, is Mexiweckelia particeps Holsinger. Based on the number of its plesiomorphic (ancestral) characters, this genus is the most primitive member of the family Hadziidae from the North American mainland.
A Contribution To The Knowledge Of The Invertebrate Cave Faunas Of Venezuela: Invertebrate Faunas Of Tropical American Caves, Part 4, Stewart B. Peck
A Contribution To The Knowledge Of The Invertebrate Cave Faunas Of Venezuela: Invertebrate Faunas Of Tropical American Caves, Part 4, Stewart B. Peck
International Journal of Speleology
The invertebrate faunas of four caves in northern Venezuela were studied. Three were dry and one was a wet cave; but guano provided the base of the food chain in all four caves. The faunas in each were strikingly different. Of 24 non-accidental species of arthropods, all were judged to be troglophiles. All were scavengers except for 5 predators, one ectoparasite, and one parasitoid.
Variation Among Populations Of The Troglobitic Amphipod Crustacean Crangonyx Antennatus Packard (Crangonyctidae) Living In Different Habitats Ii. Population Distribution, Gary W. Dickson
International Journal of Speleology
Population densities and factors affecting the distribution of the troglobitic (i.e., obligatory cavernicole) amphipod Crangonyx antennatus were examined in two distinct aquatic habitats. Observations were made seasonally for one year in six Lee Co., Virginia (U.S.A.) caves, three with mud-bottom pools and three with gravel-bottom streams. Pool habitats were found to contain greater C. antennatus densities than stream habitats, while the highest seasonal densities were recorded in August. Availability of food is considered to be the major factor allowing these increased population densities. The population distribution of C. antennatus was not found to be related to current velocity, water depth, …
Nitrification Inhibitors, Wilbur Frye
Nitrification Inhibitors, Wilbur Frye
Soil Science News and Views
Nitrogen often limits the production of nonlegume crops because of inefficiency of N fertilizers. In some cases, more than half the fertilizer N may be lost from the soil. Therefore, it is important to use it as efficiently as possible. One way in which N fertilizer efficiency may be improved is by slowing the nitrification process in the soil.
The Reclamation Of The Victory Mine Site, Vigo County, Indiana, Carla J. Badger
The Reclamation Of The Victory Mine Site, Vigo County, Indiana, Carla J. Badger
All-Inclusive List of Electronic Theses and Dissertations
This study was involved with the physical and socioeconomic aspects related to the reclamation of the Victory Mine located in Vigo County, Indiana. The Victory Mine is an abandoned slope mine which includes 165 acres of gob and slurry. During the past ten years the site has been used as a sanitary landfill utilizing the gob as a covering agent. Pollution of Honey Creek, a tributary to the Wabash River, has been caused by sediment and acid mine drainage from the Victory Mine. Possible reclamation procedures were outlined for the Victory Mine site. Physical aspects included soils, surface and ground …
The Hydrologic Factors That Control Carbonate Hardness In Kalamazoo County Lakes, Southwestern Michigan, Linda Brittain Fenner
The Hydrologic Factors That Control Carbonate Hardness In Kalamazoo County Lakes, Southwestern Michigan, Linda Brittain Fenner
Masters Theses
The range and distribution of carbonate hardness in Kalamazoo County lakes were determined and hydrologic factors thought to control hardness were evaluated. Surface-water samples were collected from thirty- five randomly selected lakes in October, 1980. Carbonate hardness ranged from 16 to 244 mg/1 with 61 percent above 120 mg/1. Ten hydrologic variables were analyzed with respect to lake hardness. Lakes with a surface-water inlet were a ll hard (greater than 180 mg/1) and lakes at least two meters higher than the approximate ground-water table were all relatively soft (less than 100 mg/1). No direct correlations were found between the other …
Growth-Form Analysis And Paleoecology Of The Corals Of The Late Ordovician Through Mid-Silurian Fish Haven And Laketown Formations, Bear River Range, North-Central Utah, Thomas B. Rich
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Morphology of corals of the Late Ordovician through mid-Silurian Fish Haven and Laketown Formations were analyzed to document adaptations to inferred enviromental conditions, i.e., (bathymetry, illumination, sedimentation, currents, and energy), under which their enclosing sediment was deposited. Specimens and data were collected from six sites. Insoluble-residue tests were performed on the corals' matrices.
Individual corallites of radial-lensoidal corals radiate in all directions. Vertical growth, however, was restricted in turbulent conditions. Umbrellic, radial-lensoidal corals feature downward facing corallites, considered to be an adaptation to a well illuminated environment.
On tabular lensoidal corals, constituent corallites faces exclusively upward, an orientation needed under …
Faunal Succession And Depositional Environments Within The Lodgepole Limestone (Early Mississippian) Of Samaria Mountain, Idaho, Gary Keith Hines
Faunal Succession And Depositional Environments Within The Lodgepole Limestone (Early Mississippian) Of Samaria Mountain, Idaho, Gary Keith Hines
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Community succession, the orderly changes a community experiences with time, is considered to be the result of either autogenic or allogenic factors working singularly or in combination. It has been further suggested that, as communities undergo succession, certain biological parameters change in a predictable manner. Examination of members 2 through 4 of the Mississippian (Kinderhook-Osage) Lodgepole Formation of Samaria Mountain, Idaho provides a means to evaluate these concepts.
Within the study section comprised of 125 beds (61.5 m thick), four rock types are recognized. These include: (1) fossiliferous wackestone (78% of beds), which ranges in color from dark-gray (N3) to …
Petrology Of The Middle Cambrian Blacksmith Formation, Southeastern Idaho And Northernmost Utah, David Paul Zelazek
Petrology Of The Middle Cambrian Blacksmith Formation, Southeastern Idaho And Northernmost Utah, David Paul Zelazek
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Blacksmith Formation of Middle Cambrian (Albertan) age was studied in southeastern Idaho and northernmost Utah. Lithology and sedimentary structures were compared with modern environments and ancient rocks to determine environments of deposition, paleo-geography, diagenetic alterations and patterns of dolomitization.
The Blacksmith Formation can be divided into five basic rock types. Rock type A has cryptalgalaminae, mudcracks, and lacks bioturbation. Rock type A is inferred to have been deposited in the upper intertidal to supratidal environment. Rock type B is extremely dolomitized and brecciated. It is inferred that rock type B was deposited in the upper intertidal to supratidal environment. …
Maine's Whitewater Rapids And Their Relevance To The Critical Areas Program, Janet Mcmahon
Maine's Whitewater Rapids And Their Relevance To The Critical Areas Program, Janet Mcmahon
Maine Collection
Maine's Whitewater Rapids and Their Relevance to the Critical Areas Program
by Janet McMahon
Planning Report No. 74, Critical Areas Program, 184 State St., Augusta, Maine,
April, 1981 (additions made in October, 1981). Reprinted July, 1983.
Contents: Introduction / Natural History of Whitewater Rapids / Methods / Criteria / Results / Conclusions / General Evaluation of Whitewater Rapids for Inclusion on the Register of Critical Areas / Bibliography / Action Plan
Palynological Correlation Of The Kentucky No. 12 Coal, Gerald E. Vyhmeister
Palynological Correlation Of The Kentucky No. 12 Coal, Gerald E. Vyhmeister
Loma Linda University Electronic Theses, Dissertations & Projects
In attempting to analyze the depositional environment for the Kentucky No. 12 Coal three columns were sampled from a 1 km area. The columns yielded 76 miospore species belonging to 33 genera, and representing in decreasing order of abundance, arborescent lycopods, tree ferns, calamites, small ferns, gymnospermous trees, seed ferns, herbaceous lycopods, and others from unknown origin.
The pattern of spore distribution in the columns did not appear to be affected by the presence of several partings, a feature which calls into question several mechanisms proposed for the origin of partings and also creates difficulties for an autochthonous origin for …
The Design Of Oxygen Rebreather Equipment For Use In Foul-Air Speleology, Donald A. Mcfarlane
The Design Of Oxygen Rebreather Equipment For Use In Foul-Air Speleology, Donald A. Mcfarlane
WM Keck Science Faculty Papers
The design of a lightweight oxygen rebreather set suitable for short duration explorations in foul-air caves is described, together with a discussion of its performance, limitations, and possible improvement.
Acidification Of Minnesota Soils By Nitrogen Fertilization And Acid Rain, Paul R. Bloom, William M. Schuh, W. W. Nelson
Acidification Of Minnesota Soils By Nitrogen Fertilization And Acid Rain, Paul R. Bloom, William M. Schuh, W. W. Nelson
Journal of the Minnesota Academy of Science
The effect of inputs of acidifying nitrogen fertilizer and acid rain on the pH of a typical Minnesota prairie agricultural soil was estimated. Experimental data from a long term continuous corn experiment at the Southwest Experiment Station near Lamberton were used to calculate the effects of nitrogen fertilizers. Acid rain effects were estimated using soil buffering data obtained in the experiment along with existing estimates of rainfall acidity. In a typical corn-soybean rotation, using 100 kg per ha of nitrogen additions to corn, a 0 .25 unit pH drop is expected in about 38 years. The estimated acidity of the …
Altered Volcanic Ash Partings In The C Coal Bed, Ferron Sandstone Member Of The Mancos Shale, Emery County, Utah, United States Geological Survey
Altered Volcanic Ash Partings In The C Coal Bed, Ferron Sandstone Member Of The Mancos Shale, Emery County, Utah, United States Geological Survey
All U.S. Government Documents (Utah Regional Depository)
When volcanic ash falls onto the surface of a peat-forming swamp and is then covered by peat, it forms a horlzontal parting that can be recognized in the subsequent coal bed. As a consequence of the acid leaching environment in the swamp, the original glassy component and some of the less resistant pyrogenic minerals in the ash alter to clay minerals, usually kaolinite.
Selected Biological Characteristics Of Streams In The Southeastern Uinta Basin, Utah And Colorado, United States Geological Survey
Selected Biological Characteristics Of Streams In The Southeastern Uinta Basin, Utah And Colorado, United States Geological Survey
All U.S. Government Documents (Utah Regional Depository)
Biological sampling was carried out during 1976-78 in five streams in the southeastern Uinta Basin, Utah and Colorado, in order to provide baseline water-quality data for an area of potential oil-shale development. The biological activity in the streams sampled generally is limited by physical factors more so than by chemical constituents and plant nutrients. Characteristics of streamflow, such as high turbidity, fluctuating water levels, and moderate to high salinity, limit production of flora and fauna biomass.
Ua66/8/3 Annual Report, Wku Geography & Geology
Ua66/8/3 Annual Report, Wku Geography & Geology
WKU Administration Documents
Annual report of activities of the WKU department of Geography & Geology.
Experimental Summaries., M W. Perry, R N. Weir
Experimental Summaries., M W. Perry, R N. Weir
Experimental Summaries - Plant Research
Wheat Yield Potential Trials, 81BA4, 81WH7, 81KAS.Wheat-Regenerating Sandplain Lupin Rotation Trials, 79GE38, 79GE42.Nitrogen x Cycocel x Foliar Nutrients x Fungicide-on Wheat,81KA6. Historical Wheat Trials, 81A3, 81C4, 81SG22, 81WH6. Time of Planting on Cereal Yields, 81NA8, 81KA55.
Treating Saltland, Department Of Agriculture, Western Australia
Treating Saltland, Department Of Agriculture, Western Australia
Journal of the Department of Agriculture, Western Australia, Series 4
No abstract provided.
Glacial Deposits, Vol. 9, 1980-1981, Department Of Geography-Geology
Glacial Deposits, Vol. 9, 1980-1981, Department Of Geography-Geology
Glacial Deposits
Newsletter of the Department of Geography-Geology
Grain Legume Agronomy Programme, G Walton
Grain Legume Agronomy Programme, G Walton
Experimental Summaries - Plant Research
Lupin agronomy, series 1 - growth factor interactions. To evaluate the relative influence that various growth factors exert on crop yield. Lupin agronomy, series 2 - harvest index response to density. To establish whether the harvest index of the plants at maximum crop yield density remains constant over a range of environmental conditions and whether differences exist between cultivars. Lupin agronomy - nutrition. To compare the grain yield response to potash rates. Grain legumes for wheatbelt rotations. To compare the soil fertility after one year growth of different legume species. In the 1981 experiments, Derrimut field pea yielded well, outyielding …