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Articles 16831 - 16860 of 17789
Full-Text Articles in Entire DC Network
Grain Legume Agronomy Program, G H. Walton
Grain Legume Agronomy Program, G H. Walton
Experimental Summaries - Plant Research
Lupin Agronomy - varieties x environment - Wongan Hills R.S., Badgingarra R.S., Newdegate R.S., Mt Barker R.S. Lupin Agronomy - morphology x split seed – Mr J. wood, “Karakin”, Lancelin. Lupin Agronomy - Erregulla regeneration and rotation – Lancelin, Moora, Watheroo. Grain legume species comparison – 84ES1, 84LG38, 84MO10, 84ES1. Field pea evaluation – varieties. Aim: To compare the biological and seed yield adaptation to environment between morphological types of field pea. Field pea agronomy – 84KA18, 84LG25, 84ME42, 84MO33, 84MO34, 84N16, 84SG20, 84SG28. Sowing time x seed rate. Pea and wheat response to applied P – 84LG24, 84ME43, 84NO46, …
The Ecology Of Skeleton Weed .(Chondrilla Juncea L.) In Western Australia , Afghan Thistle (Solanum Hoplopetalum) Ecology, J. Dodd
Experimental Summaries - Plant Research
1. The ecology of skeleton weed .(Chondrilla juncea L.) in Western Australia - 84PE18 Seed production and water use in the glasshouse. 1.2 Seed production and water use of field-grown skeleton weed (84BA17, 84BA18). Water use. 1.3 Germination in relation to soil water content. 2. Afghan thistle (Solanum hoplopetalum) ecology. 2.1 Water relations (84N048). 2.2 Growth in Afghan thistle (84N050). 2.3 Afghan thistle reproductive biology (84N049, 84N063, 84PE19).
Effect Of Various Crop And Pasture Species On The Growth Of A Subsequent Wheat Crop, N Delroy, J W. Bowden, I Rowland, M Ralph, R Lunt, M Baker
Effect Of Various Crop And Pasture Species On The Growth Of A Subsequent Wheat Crop, N Delroy, J W. Bowden, I Rowland, M Ralph, R Lunt, M Baker
Experimental Summaries - Plant Research
83WH29: The effect of various crop and pasture species on the growth of a subsequent wheat crop. Aim: To characterise the effect of various crop and pasture species on the growth and yield components of a subsequent wheat crop with special emphasis on the nitrogen nutrition of that crop. To provide validation data for modelling wheat growth and nitrogen uptake. Measurements: Factors to be monitored through time were; Soil moisture profiles; Mineral nitrogen profiles; Root growth profiles; Top growth and nitrogen uptake; Development score; Incidence of disease and pests.
Seasonal notes, trial design, weed diseases and pests. Results: The results …
Tackling The Problem Off The Farm, C M. Croft
Tackling The Problem Off The Farm, C M. Croft
Journal of the Department of Agriculture, Western Australia, Series 4
Methods of redusing phosphorus losses from the catchment soils of the Peel-Harvey esturine system have been discussed in other articles in this Journal.
This article briefly discusses a range of 'off the farm' techniques to improve phosphorus flushing from Peel Inlet or Harvey Estuary to the sea and to treat the phosphorus and the algae. These techniques were among more than 100 management options evaluated by the Peel-Harvey Study Group.
Gradual Phyletic Evolution At The Generic Level In Early Eocene Omomyid Primates, Kenneth D. Rose, Thomas M. Bown
Gradual Phyletic Evolution At The Generic Level In Early Eocene Omomyid Primates, Kenneth D. Rose, Thomas M. Bown
United States Geological Survey: Staff Publications
Analysis of dental morphology in over 600 stratigraphically controlled specimens of tarsier-like primates from early Eocene strata in Bighorn Basin, Wyoming, provides important new data for understanding the tempo and mode of evolution in primates.
The Marine Biogeochemistry Of Selenium: A Re-Evaluation, Gregory A. Cutter, Kenneth W. Bruland
The Marine Biogeochemistry Of Selenium: A Re-Evaluation, Gregory A. Cutter, Kenneth W. Bruland
OES Faculty Publications
Vertical and horizontal profiles from the North and South Pacific Oceans demonstrate the existence of three species of dissolved selenium: selenite, selenate, and organic selenide (operationally defined). In surface waters, organic selenide makes up about 80% of the total dissolved selenium, selenite concentrations are uniformly low, and selenate concentrations rise with increased vertical mixing. The organic selenide maximum (thought to consist of seleno-amino acids in peptides) coincides with the maxima of primary productivity, pigments, bioluminescence, and dissolved free amino acids. Deep ocean waters are enriched in selenite and selenate, while organic selenide is nondetectable. In suboxic waters of the tropical …
The Effects On Plant Growth, W M. Porter, J. S. Yeates
The Effects On Plant Growth, W M. Porter, J. S. Yeates
Journal of the Department of Agriculture, Western Australia, Series 4
The level of acidity of a soil reflects its chemical and sometimes its biological condition. Changes in acidity mean changes in the availability to plants of some soil elements, and modifications to the biological processes in the soil.
Some elements become more available to plants in acis soils, and in some soils particular elements can reach toxic levels. Other elements can be effected in the opposite way: deficiencies can develop in acid conditions.
It is important to realise, however, that the chemical nature of all soils varies. Beccause of these variations, acidity can affect each soil differently and thus influence …
Groundwater-Lake Interactions, Wood Lake, Benson County, North Dakota, Lori J. Ferguson
Groundwater-Lake Interactions, Wood Lake, Benson County, North Dakota, Lori J. Ferguson
Theses and Dissertations
Wood Lake is a kettle lake within the McHenry end moraine (late Wisconsinan) in eastern Benson County, North Dakota. It is part of the Devils Lake interior basin, near the drainage divide between the Devils Lake basin and the Big Coulee - Sheyenne River drainage. The moraine deposits, part of the Coleharbor Group, are composed of complexly interfingering lenses of gravel, sand, silt, and clay within the till.
Water levels in piezometers around Wood Lake indicate groundwater flows from the southwest into the west side of the lake and out of the lake along the east shore, toward the northeast. …
Glacial Deposits, Vol. 12, 1983-1984, Department Of Geography-Geology
Glacial Deposits, Vol. 12, 1983-1984, Department Of Geography-Geology
Glacial Deposits
Newsletter of the Department of Geography-Geology
Conodonts Of The Bakken Formation (Devonian And Mississippian), Williston Basin, North Dakota, Michael D. Hayes
Conodonts Of The Bakken Formation (Devonian And Mississippian), Williston Basin, North Dakota, Michael D. Hayes
Theses and Dissertations
The Bakken Formation is a thin (maximum 145 ft., 44 m), predominantly elastic unit in the subsurface of the Williston Basin in the United States and Canada. The formation consists of two, mostly non-calcareous, grayish-black to brownish-black shales separated by light to dark gray, calcareous and dolomitic siltstone and fine-grained sandstone. The carbonaceous, black shales of the Bakken produce a distinctive geophysical marker and are a major source rock for hydrocarbons in the Williston Basin.
Conodonts were selectively sampled from cores of the Bakken in North Dakota in an effort to determine the age and thermal maturity of the formation. …
Nitrogen Flows From Several Species And Varieties Of Legume, John Hamblin Dr
Nitrogen Flows From Several Species And Varieties Of Legume, John Hamblin Dr
Experimental Summaries - Plant Research
Trial 83C24: N flows from several species and varieties of legume.
Trial 83C27: The effect of seeding rate, planting and variety on the residual value of lupins.
Trial 84C25: Small rotation trial for 1985.
Trial 84C34: Nitrogen response on large rotation plots at ECRS.
These trials were carried out in collaboration with: Mr R. Delane, and with assistance from: Mr. T. White, Ms. A. Bishop.
Investigation Of Root And Foliar Diseases Associated With Decline In Wheat Yields On Sandplain, Jill Wilson
Investigation Of Root And Foliar Diseases Associated With Decline In Wheat Yields On Sandplain, Jill Wilson
Experimental Summaries - Plant Research
A Wheat Industry Research Council Project. In 1984 research was conducted in collaboration with Dr John Hamblin, Dr Allan Brown, Mr Rob Delane and Dr Mark Sweetingham. 1. Field Trial (GE84Cl5): Interactions between disease and agronomic factors, particularly rotation with lupins, and deep tillage. ( i) Yields, (ii) Incidence of root diseases, (iii) Root length and diseased root length, (iv) Leaf disease. 2. Farm Survey (sites from trial 84GE57 of Dr Allan Brown) Incidence of Common Root Rot
Investigations And Research In Nevada By The Water Resources Division, U. S. Geological Survey, 1982-83, Terry Katzer, Otto Moosburner, William D. Nichols
Investigations And Research In Nevada By The Water Resources Division, U. S. Geological Survey, 1982-83, Terry Katzer, Otto Moosburner, William D. Nichols
Publications (WR)
The Water Resources Division, U.S. Geological Survey, is charged with (1) maintaining a hydrologic network in Nevada that provides information on the status of the State's water resources and (2) engaging in technical water-resources investigations that have a high degree of transferability. To meet these broad objections, 26 projects were active in Nevada during fiscal year 1982 in cooperation with 36 Federal, State, and local agencies. Total funds were $3,319,455, of which State and local cooperative funding amounted to $741,500 and Federal funding (comprised of Geological Survey Federal and cooperative programs plus funds from six other Federal agencies) amounted to …
Sediment Oxygen Demand In Streams Receiving Sewage Effluent, John J. Schultz
Sediment Oxygen Demand In Streams Receiving Sewage Effluent, John J. Schultz
Masters Theses
Sediment oxygen demand is an important factor in determining dissolved oxygen concentrations in streams and rivers subjected to sewage effluents and other sources of organic pollution. Resuspension of sediments during bottom-scouring after periods of heavy precipitation exerts an immediate and increased oxygen demand on the water and is expected to decrease sediment oxygen demand at the site.
Sediment samples were collected monthly from April through November, 1983 from three small streams subjected to sources of organic pollution. The samples collected were arbitrarily categorized into wet and dry period samples based on the total precipitation between collection dates. Sediment oxygen demand …
Disposal Of Household Wastewater In Soils Of High Stone Content (1981-1983), E. M. Rutledge, C. R. Mote, D. T. Mitchell, M. S. Hirsch, M. D. Harper, H. D. Scott, C. L. Griffis
Disposal Of Household Wastewater In Soils Of High Stone Content (1981-1983), E. M. Rutledge, C. R. Mote, D. T. Mitchell, M. S. Hirsch, M. D. Harper, H. D. Scott, C. L. Griffis
Arkansas Water Resources Center Technical Reports
Four experimental filter fields were constructed with built-in monitoring equipment in Nixa soils. These soils contain many chert fragments and a fragipan about 60 cm below the soil surface. The fragipan restricts downward movement of water and is the designlimitingfeature. The four filter fields were: 1. A "standard" filter field, 76 cm deep. The bottom of the trench was in the fragipan. 2. A "modified standard" filter field, 30 cm deep. The bottom of the trench was above the fragipan. 3. A "modified pressure" filter field, 40 cm deep. The bottom of the trench was above the fragipan. In addition, …
The Effect Of Polynuclear Aromatic Hydrocarbons On The Fecundity Of Acartia Tonsa (Calanoid Copepoda), Juanita Y. Grabarczyk
The Effect Of Polynuclear Aromatic Hydrocarbons On The Fecundity Of Acartia Tonsa (Calanoid Copepoda), Juanita Y. Grabarczyk
OES Theses and Dissertations
The concentrations of polynuclear aromatic hydrocarbons (PNAHs) were determined for several stations in the Elizabeth River. Thirteen PNAHs of the sixteen EPA priority pollutant PNAHs were present in the particulate fraction. The concentrations ranged from 10.0 ng/1 to 1000 ng/1. Ten of the sixteen EPA priority pollutant PNAH were present in the dissolved phase. Concentrations ranged from 2.0 ng/1 to 100 ng/1.
The environmental PNAHs concentrations were used to determine test concentrations. Bioassays were conducted to determine the effects of indigenous concentrations of seven predominant PNAHs (0.01 mg/1 to 2.4 mg/1 concentrations) on the fecundity of Acartia tonsa (calanoid Copepoda). …
Depositional Environments Of Siliceous Laminites In The Laney Member Of The Green River Formation, Sublette County, Wyoming, Michael G. Rasmussen
Depositional Environments Of Siliceous Laminites In The Laney Member Of The Green River Formation, Sublette County, Wyoming, Michael G. Rasmussen
Loma Linda University Electronic Theses, Dissertations & Projects
Siliceous shales of the Laney Member of the Green River Formation are exposed in outcrops around Fontenelle Reservoir in the northwest corner of the Green River Basin, Wyoming. An analysis of these shales is important to an understanding of the origin of laminites in the Green River formation. The shales are rhythmic, varve -like laminites, composed of quartz, authigenic potassium feldspar , dolomite, and zeolite minerals. The association of these minerals suggest that the original sediment contained significant amounts of volcanic ash, and were deposited in a shallow, near-shore, oxygenated saline - alkaline lake environment, as inferred from (1) the …
Atlas Of Wetlands In The Principal Coal Surface Mining Region Of Western Kentucky, William J. Mitsch, Jan R. Taylor, Kimberly B. Benson, Paul L. Hill Jr.
Atlas Of Wetlands In The Principal Coal Surface Mining Region Of Western Kentucky, William J. Mitsch, Jan R. Taylor, Kimberly B. Benson, Paul L. Hill Jr.
KWRRI Research Reports
This atlas contains maps of wetlands and surface mining activity in the Western Kentucky Coal Field, and focuses on a 3960 km2 (1530 mi2) region where approximately 90 percent of surface mining in the Coal field occures. Some present and potential competition exists between surface coal mining and wetland protection. A wetland classification, based on the recent FWS classification, includes six types of palustrine systems and one each of riverine and laucstrine systems. Wetlands and surface mines are located on twenty-seven 7.5 minute USGS quadrangles that define the study region. A total of 460 km2 (177 …
Modeling Surface And Subsurface Stormflow On Steeply-Sloping Forested Watersheds, Patrick G. Sloan, Ian D. Moore, George B. Coltharp, Joseph D. Eigel
Modeling Surface And Subsurface Stormflow On Steeply-Sloping Forested Watersheds, Patrick G. Sloan, Ian D. Moore, George B. Coltharp, Joseph D. Eigel
KWRRI Research Reports
A simple conceptual rainfall-runoff model, based on the variable source area concept, was developed for predicting runoff from small, steep-sloped, forested Appalachian watersheds. Tests of the model showed that the predicted and observed daily discharges were in good agreement. The results demonstrate the ability of the model to simulate the "flashy" hydrologic behavior of these watersheds.
Five subsurface flow models were evaluated by application to existing data measured at Coweeta on a reconstructed homogeneous forest soil. The five models were: Nieber 's 2-D and 1-D finite element models (based on Richards' equation), the kinematic wave equation, and two simple storage …
Agenda: Groundwater: Allocation, Development And Pollution, University Of Colorado Boulder. Natural Resources Law Center
Agenda: Groundwater: Allocation, Development And Pollution, University Of Colorado Boulder. Natural Resources Law Center
Groundwater: Allocation, Development and Pollution (Summer Conference, June 6-9)
Even before the [Natural Resources Law] Center was established [in the fall of 1981], the [University of Colorado] School of Law was organizing annual natural resources law summer short courses. To date four programs have been presented:
- July 1980: "Federal Lands, Laws and Policies-and the Development of Natural Resources"
- June 1981: "Water Resources Allocation: Laws and Emerging Issues"
- June 1982: "New Sources of Water for Energy Development and Growth: lnterbasin Transfers"
- June 1983: "Groundwater: Allocation; Development and Pollution"
(Reprinted from Resource Law Notes, no. 1, Jan. 1984, at 1.)
University of Colorado School of Law professors …
The Geology Of Maine's Coastline : A Handbook For Resource Planners, Developers, And Managers, Maine State Planning Office
The Geology Of Maine's Coastline : A Handbook For Resource Planners, Developers, And Managers, Maine State Planning Office
Maine Collection
The Geology of Maine's Coastline : A Handbook for Resource Planners, Developers, and Managers
Executive Department, Maine State Planning Office, Augusta, Maine, June 1983.
Contents: List of Figures / Introduction: The Geological Connection / Chapter 1: Using the Marine Environments Maps / Chapter 2: Perspectives of the Maine Coast / Chapter 3: The Building Blocks of Maine's Coast / Chapter 4: The Disappearing Shoreline / Where to Go for Help / Some Planning Considerations for Development in Coastal Geologic Environments / Land Use Laws of Special Interest to Individual Coastal Property Owners
Disposal Of Household Wastewater In Soils Of High Stone Content (1977-1980), E. M. Rutledge, C. R. Mote, M. S. Hirsh, H. D. Scott, D. T. Mitchell
Disposal Of Household Wastewater In Soils Of High Stone Content (1977-1980), E. M. Rutledge, C. R. Mote, M. S. Hirsh, H. D. Scott, D. T. Mitchell
Arkansas Water Resources Center Technical Reports
Two experimental septic tank filter fields were constructed with built-in monitoring equipment in Nixa soils. These soils contain many chert fragments and a fragipan about 60 cm deep which restricts downward water movement and is the design-limiting feature. The standard filter field (76 cm deep) was built into the fragipan and the modified standard filter field (30 cm deep) was placed above it. During 30 months' observation, the modified standard performed better than the standard filter field. Maximum rise of effluent in the standard and modified standard came within 11 and 19 cm of the soil surface, respectively. Performance of …
Sedimentation Rate Of Salt Determined By Micrometeorite Analysis, James Matthew Barnett
Sedimentation Rate Of Salt Determined By Micrometeorite Analysis, James Matthew Barnett
Masters Theses
The sedimentation rate of the A-l Evaporite of Michigan was determined by analysis of micrometeorites found as inclusions in the halite deposit. The samples were obtained from the Dow Chemical Company salt well number eight. The residue from the dissolved salt was magnetically separated and later analyzed by Particle Induced X-ray Emission (PIXE), X-ray diffraction , and microprobe techniques. The amount of extraterrestrial material was determined from the quantity of nickel present.
A sedimentation rate of .01 to .4 centimeters per year was calculated for the salt based on a constant influx rate of meteoritic material of 1 x 10 …
The Chemical Composition Of Lakes In The North-Central United States, Eville Gorham, Walter E. Dean, Jon E. Sanger
The Chemical Composition Of Lakes In The North-Central United States, Eville Gorham, Walter E. Dean, Jon E. Sanger
United States Geological Survey: Staff Publications
Lake waters of the north-central U.S.A. are classified into five groups, based on increasing specific conductivity and changes in ionic composition from east to west, from Wisconsin through Minnesota to North and South Dakota. The most dilute group of waters has specific conductivities <29 μnhos x cm-1 at 25°C; the most concentrated group has specific conductances that range from 7,000 to 73,000 μmhos. As conductivity increases all major ions increase, but there is a shift in cation dominance from Ca2+ to Mg2+ to Na+, and in anion dominance from HCO3- to SO42-. This shift …29>
Kentucky's Ipm Program For Alfalfa, Chris M. Christensen
Kentucky's Ipm Program For Alfalfa, Chris M. Christensen
Kentucky Alfalfa and Stored Forage Conference
Integrated Pest Management (IPM) is a concept that encourages the use of a variety of strategies in the management of crop pests. It is very important to have an indepth understanding of the crop production system when implementing an IPM program. An IPM program is dynamic requiring a continual evaluation of the status of the crop, the associated pest complex, the effects of the pests and the biological deterrents to those pests. If a pest population gets "out of hand" and begins to cause economic damage, pest management techniques may need to be applied. These pest management measures may be …
Drainage Basin Characteristics Of The Minnesota River, Paul Fasching
Drainage Basin Characteristics Of The Minnesota River, Paul Fasching
Journal of the Minnesota Academy of Science
The geomorphology of the Minnesota River Basin is poorly understood, yet much of modern fluvial ecology requires this information as a prerequisite to physical, chemical, or biological studies. The purpose of this paper is to provide background descriptive geomorphological river basin data for the Minnesota River. Eleven descriptive parameters (river gradient, Form f, Shape 1, Shape 2, circularity ratio, elongation ration, stream order, bifurcation ratio, average area by order, number of lakes per order and number of lower order streams entering higher streams) were determined for the Minnesota River Basin as a whole as well as for ten subbasins. A …
Ua35/11 Student Honors Research Bulletin, Wku Honors Program
Ua35/11 Student Honors Research Bulletin, Wku Honors Program
WKU Administration Documents
The WKU Student Honors Research Bulletin is dedicated to scholarly involvement and student research. These papers are representative of work done by students from throughout the university.
- Albin, Bettye. John Dryden's Criticism: The Neglected Link
- Allen, Christopher. Martial Reflections: Ancient Cultures and Their War-Gods
- Case, Laura. Climatic Preference
- Deller, Kathy. Regression Analysis: The Effects of Advertising, Price, Income and Import Sales on American-Made Auto Sales
- Downing, Elizabeth. Dorothy Leigh Sayers: Detective of Literary Theory in The Mind of the Maker
- Elder, Janice. A Retrospective Study on Discharge Planning and Primiparas at Breckinridge Memorial
- Flora, Joan. Narcissism and the Need for …
Histological Differentiation Among Abiotic Causes Of Conifer Needle Necrosis, United States Department Of Agriculture, Forest Service
Histological Differentiation Among Abiotic Causes Of Conifer Needle Necrosis, United States Department Of Agriculture, Forest Service
Forestry
Symptoms induced by phytotoxic gases within conifer needles can be differentiated histologically from those caused by other abiotic agents including winter drying, drought, and salt. However, it is not possible to differentiate among symptoms caused by hydrogen fluoride, sulfur dioxide, ethyl mercaptan, and hydrogen sulfide. Phytotoxic gases cause hypertrophy and hyperplasia of vascular parenchyma, endodermis collapse, and intense vascular staining. The other abiotic agents induce mesophyll collapse with little or no observable effects on vascular tissues. Histological analyses should be useful in diagnosis of air pollution-induced injury and damage in coniferous forests.
Winter Injury Of Sagebrush And Other Wildland Shrubs In The Western United States, United States Department Of Agriculture, Forest Service
Winter Injury Of Sagebrush And Other Wildland Shrubs In The Western United States, United States Department Of Agriculture, Forest Service
Forestry
The objective of this paper is to briefly review winter injury of plants and shrubs in particular, document the observed winter injury of 1976-77, and correlate the occurrence with weather records.
Estimating The Rate And Amount Of Tree Loss From Mountain Pine Beetle Infestations, United States Department Of Agriculture, Forest Service
Estimating The Rate And Amount Of Tree Loss From Mountain Pine Beetle Infestations, United States Department Of Agriculture, Forest Service
Forestry
Because of recurrent depredations by the mountain pine beetle in lodgepole pine, managers have less than a 50 percent chance of growing lodgepole pine to 16-inch diameters in most stands. This paper describes a Rate of Loss Model that estimates the amount of tree and volume loss per year and the longevity of the infestation, and shows how the model can be incorporated into forest planning. The model assumes optimum conditions for the life of an epidemic. However, actual field conditions can cause beetle populations to deviate from predictions causing a bit of overestimation, which is not considered serious in …