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Articles 54781 - 54810 of 59385
Full-Text Articles in Entire DC Network
Interceptor Drains And Waterlogging Control, J W. Cox, T R. Negus
Interceptor Drains And Waterlogging Control, J W. Cox, T R. Negus
Journal of the Department of Agriculture, Western Australia, Series 4
Department of Agriculture trials of seepage interceptor drains from 1972 to 1983 primarily assessed the effects of such drains on salt encroachment. Although these trials showed that the drains had little influence on salt storage within the topsoil, they did reduce waterlogging downslope.
To investigate this drainage effect further, the Department's Narrogin office surveyed 35 drains on 14 properties in the winter of 1981, followed by detailed crop measurements in December that year. Provided the drains were properly designed, surveyed and constructed, and well maintained, they could be expected to increase crop yields during a waterlogging year by about 1 …
Assessment Of Waterlogged Sites, D J. Mcfarlane
Assessment Of Waterlogged Sites, D J. Mcfarlane
Journal of the Department of Agriculture, Western Australia, Series 4
Soil is said to be waterlogged if any part of the plant root zone is saturated with water. In severe cases soil is saturated to the surface and waterlogging is obvious. Waterlogging is distinguished from flooding in which surface runoff brings down water from higher up in a catchment. However, flooding may result in waterlogged sites.
Depositional Environments And Petrology Of The Felix Coal Interval (Eocene), Powder River Basin, Wyoming, Peter D. Warwick
Depositional Environments And Petrology Of The Felix Coal Interval (Eocene), Powder River Basin, Wyoming, Peter D. Warwick
Theses and Dissertations--Earth and Environmental Sciences
A study of a 250 ft. (76.2 m) stratigraphic interval that includes the Eocene-age Felix coal of the Wasatch Formation was undertaken in the Powder River Basin of Wyoming to establish a depositional model based on the interrelations of coal-seam geometry, coal maceral composition, and spatial distribution of adjoining rocks. Regional cross sections and maps of major rock bodies were prepared from 147 measured stratigraphic sections and 56 geophysical logs. Trends in maceral and chemical properties within the Felix coal were identified from petrographic and geochemical analyses of 72 coal channel samples. The combined data sets indicate that the thickest …
The Holocene Carbonate Eolianites Of North Point And The Modern Marine Environments Between North Point And Cut Cay, Brian White, H. Allen Curran
The Holocene Carbonate Eolianites Of North Point And The Modern Marine Environments Between North Point And Cut Cay, Brian White, H. Allen Curran
Geosciences: Faculty Publications
The goals of this part of the field trip are to study the types of strata, sedimentary structures, trace fossils, and dune morphologies of the Holocene eolianites excellently exposed along the coasts of Rice Bay and North Point. We will show how eolian deposition of carbonate grains occurs and how dunes are initiated and evolve. Toward the end of this excursion, a short snorkel dive will be conducted in the shallow, sheltered waters between North Point and Cut Cay to study grass beds, sandy substrates, and hardgrounds and to compare their associated sediments, plants, and animals. The area to be …
Boron Toxicity In Barley., M. M. Riley, J. W. Gartrell, R. F. Brennan, T. N. Kahn
Boron Toxicity In Barley., M. M. Riley, J. W. Gartrell, R. F. Brennan, T. N. Kahn
Experimental Summaries - Plant Research
Field trials. Intraspecific variation in Barley to Boron toxicity, 85Me55, 85SG29, 85SG33. Glasshouse experiments. Sampling techniques for Boron toxicity in Barley, 85GL2. Cartwright rating system, leaf rating system.
Residual Value Of Legumes., J. Hamblin, R. Delane, G. Adam, A Bishop
Residual Value Of Legumes., J. Hamblin, R. Delane, G. Adam, A Bishop
Experimental Summaries - Plant Research
This report examines the residual value of lupins and several other species grown at ECRS in 1984 on the yield of wheat in 1985 (85 C 25). 85 C 46 examined the residual effect of several lupin species and varieties grown under different nutritional treatments in 1984 at two sites differing in rainfall on wheat yields in 1985. 85 C 47 examines the interaction between levels of applied potassium and deep cultivation (ripping) on the yield of wheat at a low K, dry site.
Report on 85 C 27, 85 C 46 and 85 C 47.
Pasture Research Programme For The Medium Rainfall Zone Of W.A. Species Selection And Management Related In Particular To The Ryegrass Toxicity Problem (Fund 492/0035)., C. K. Revell, C. W. Thorn
Pasture Research Programme For The Medium Rainfall Zone Of W.A. Species Selection And Management Related In Particular To The Ryegrass Toxicity Problem (Fund 492/0035)., C. K. Revell, C. W. Thorn
Experimental Summaries - Plant Research
Species evaluation, 85KA69, 85 KA 70, 85 KA 94, 85 KA 68. Small plot evaluation, 85 KA 89, 8S KA 90. Long term medic species evaluation, 82 KA 44, 82 KA 45. Drill run evaluation of M. polymorpha, 84 KA 38, 84 KA 39, 84 KA 40. Species characterization trials, 83 KA 66, 83 KA 67. Serradella evaluation, 85 KA 72, 85 KA 73, 85 KA 74, 85 KA 76
Organic Source Of Nitrogen Trials & Miscellaneous Trials., J. W. Bowden, A. Diggle, R. J. Lunt
Organic Source Of Nitrogen Trials & Miscellaneous Trials., J. W. Bowden, A. Diggle, R. J. Lunt
Experimental Summaries - Plant Research
1. Nitrogen sources Badgingarra 85BA3 Organic Source of Nitrogen 8SBA4 Interaction of Organic and Inorganic Nitrogen sources 85BAS Miscellaneous Organic Nitrogen Sources 85BA39 Times and Levels of Inorganic Nitrogen Application Lancelin 85M02 Organic sources of nitrogen 85M03 Interaction of Organic and Inorganic Nitrogen Sources 85M04 Miscellaneous Organic Nitrogen Sources 85MOS3 Times and Levels of Inorganic Nitrogen Application Meckering 85N01 Organic Sources of Nitrogen 85N03 Miscellaneous Organic Nitrogen Sources 85NOS9 Times and Levels of Inorganic Nitrogen Application 2. Miscellaneous trials 84M6 Rates of Nitrogen on Wheat - CSIRO Megatrial (E. Harvey) 85M4 Nitrogen and Water on Wheat (with M. Mason) 83WH29 …
Weed Seed Ecology., A. H. Cheam
Weed Seed Ecology., A. H. Cheam
Experimental Summaries - Plant Research
Emergence of weed seedlings from different soil depths. 82MT49, Mt Barker Research Station. 83MT4, Mt Barker Research Station. 82NR12, Northam Research Station. 83NR2, Northam Research Station. 82C37, Chapman Research Station. 83C3, Chapman Research Station. Longevity of buried weed seeds. 82MT50, Mt Barker Research Station. 83MT5, Mt Barker Research Station. 82NR13, Northam Research Station. 83NR3, Northam Research Station. 82C38, Chapman Research Station. 83C4, Chapman Research Station. Emergence of weed seedlings in relation to soil type and cultivation. 82PE32, South Perth. Emergence and fate of weed seeds in different depths of cultivated and undisturbed compacted soil. 84C49, Chapman Research Station. 84MT62, Mt …
Low Rainfall Pasture Project., M. A. Ewing
Low Rainfall Pasture Project., M. A. Ewing
Experimental Summaries - Plant Research
Variety experiments, rows 85M53, small plots 85M54, large plots, 85M43, 85N21, 85ME49, 85M44. defoliation comparison, 85M41. Pasture establishment systems, 85N25, 85N26, 85M52, 85M45, 85M46, 85M47, 85ME61, 85M62, 85M63. Cereals following pastures, 84M42, 84M43, 84M56, 84M57, 84LG34. Pasture wheat rotation, 82WH39, 82M47.
Long Term Rotation Trials, Lupins: Wheat Rotation., I. Rowland, W. Hawkins
Long Term Rotation Trials, Lupins: Wheat Rotation., I. Rowland, W. Hawkins
Experimental Summaries - Plant Research
Long term rotation trials 66M29, 67C13, 67N4, 68E5, 65SG5, 73SG16, Lupins : wheat rotation 80TS3, 82TS2, 82M26.
Soil Acidity - High Rainfall Pastures., J. S. Yeates, M. F. Clarke, D. A. Tooke, R. A. Deyl
Soil Acidity - High Rainfall Pastures., J. S. Yeates, M. F. Clarke, D. A. Tooke, R. A. Deyl
Experimental Summaries - Plant Research
Aims of the Project (i) To establish the current pH of the cultivated soils of the high rainfall areas of south-west Western Australia, and the extent to which pH has altered since clearing. (ii) To examine the responsiveness of old land pastures with low current soil pH levels (< 5.5 water) to applied lime. (iii) To relate the responsiveness of subterranean clover-based pastures to measured soil parameters. 80BU14, 81AL10, 81AL12, 81BU18, 81BY18, 81BY25, 81BY26, 82AL4, 82AL5, 82AL55, 82BU7, 82HA35, 82HA36, 82PE1, 82MA20, 83AL7, 83AL9, 83AL10, 83ALll, 83BY29, 84BU9, 84BU10, 84BY37, 84HA21, 84HA37, 84MA21.
Copper And Zinc Nutrition Experimental Results., J. W. Gartrell, R. F. Brennan, M. M. Riley
Copper And Zinc Nutrition Experimental Results., J. W. Gartrell, R. F. Brennan, M. M. Riley
Experimental Summaries - Plant Research
Long term copper trial - Newdegate research station, 66N14. Copper, zinc and sulphur residual with DAP for wheat, 78WH66. Copper and zinc residual with dap 78Mo36. Zinc residual with high analysis n.p. fertiliser for wheat 80no31. Zinc residual with high analysis n.p. fertiliser for wheat 79me22, 79me23. Zinc residual with high analysis n.p. fertiliser for wheat 82mo8. Zinc, copper and sulphur residual with DAP, 781G27. Methods of copper application on new land, 85JE48. Evaluation of copper ore 85LG47. Zinc by nitrogen interaction, 85LG28. Zinc residual with DAP, 85LG29. Copper sulphate, copper chelate and copper oxychloride effectiveness for wheat, 85LG26. Zinc …
Phosphorus Nutrition., M. D. Bolland, M. J. Baker, C. H. Phillips
Phosphorus Nutrition., M. D. Bolland, M. J. Baker, C. H. Phillips
Experimental Summaries - Plant Research
Trials reported on: 85 NA 34, 85 NA 35, 85 NO 63, 85 BA 34, 85 BA 36, 85 BA 37, 76 WH 9, 84 E 31, 84 M 63, 84 NO 69, 77 MT 2, 78 BA 7, 65 A 1, 69 WH 15.
Effect Of Soil Type On Relative Crop Yields, Effect Of Seeding Time On Pea And Lupin Yields, Effect Of Seeding Rate On Field Pea Yields, Studies In Legume Nodulation And Response Of Cereals In The Year Following Legumes., R. French
Experimental Summaries - Plant Research
Trials 85M36, 85M37, 85M38, 85M39. Trials 8SJE17, 85KA62, 85N20, 85ME42, 85ME43, 85ME44, 85WH48. Trials 85KA63, 85M33. Trials 85M32, 85M34, 85M35. Trials 84M50, 84M51, 84M52.
Long Term Minimum Tillage Investigations, Stubble Management Techniques, Deep Ripping And Seeding Machine Comparisons., R. J. Jarvis, L. G. Butcher, L. D.J. Smith
Long Term Minimum Tillage Investigations, Stubble Management Techniques, Deep Ripping And Seeding Machine Comparisons., R. J. Jarvis, L. G. Butcher, L. D.J. Smith
Experimental Summaries - Plant Research
77 A 16, red/brown sandy loam. 77 WH 17, yellow clayey-sand (Wongan loamy sand). 77 M 13, red sandy clay loam (salmon gum, gimlet). 78 M 25, Yellow acid loamy sand (Wodgil). 77 Mt 15 Gravelly loamy sand/sandy loam - forest soil 77 E 18, fine white sand over fine sandy clay. 77 A 43, Brown loamy sand/sandy loam - Jam country.77 WH 88, Grey loamy sand over gravel at 50 cm - Elphin soil series – Mallee. 77 M 56, Red sandy clay loam - Salmon Gum, Gimlet. 82 M 35, Loamy sand/sandy loam – Mallee. 77 E 52, …
Weed Seed Ecology, A H. Cheam
Weed Seed Ecology, A H. Cheam
Experimental Summaries - Plant Research
Emergence of weed seedlings from different soil depths. 82MT49, Mt Barker Research Station. 83MT4, Mt Barker Research Station. 82NR12, Northam Research Station. 83NR2, Northam Research Station. 82C37, Chapman Research Station. 83C3, Chapman Research Station. Longevity of buried weed seeds. 82MT50, Mt Barker Research Station. 83MT5, Mt Barker Research Station. 82NR13, Northam Research Station. 83NR3, Northam Research Station. 82C38, Chapman Research Station. 83C4, Chapman Research Station. Emergence of weed seedlings in relation to soil type and cultivation. 82PE32, South Perth. Emergence and fate of weed seeds in different depths of cultivated and undisturbed compacted soil. 84C49, Chapman Research Station. 84MT62, Mt …
Stubble Retention Effects On Soil Water Storage And Yield., D. Tennant
Stubble Retention Effects On Soil Water Storage And Yield., D. Tennant
Experimental Summaries - Plant Research
Merredin Research Station on red brown earth soil type, 84M1, 84M5. Summer data. Winter data.
Farm Systems Research Involving New Pasture Species., C. W. Thorn, C. K. Revell
Farm Systems Research Involving New Pasture Species., C. W. Thorn, C. K. Revell
Experimental Summaries - Plant Research
The effect of grazing on Circle Valley medic production. Effect of rotations on M. polyrnorpha production and persistence and cereal crop yields, 84 KA 35, 85 LG 44, 84 KA 37 Effect of tillage x gypsum x nitrogen on continuous cereal production, 84 KA 28. Effect of gypsum x seeding rate on the seed yield of three pasture legumes. Pasture species tolerance to grass and broadleaf herbicides. Undersowing cereal crops with burr medic.
Grain Legume Agronomy Programme., G. H. Walton
Grain Legume Agronomy Programme., G. H. Walton
Experimental Summaries - Plant Research
Lupin agronomy, 85AL4, 85AL6, 85M05, 85PE13, 81M029, 81M030, 81M027. Grain legume crop comparisons, 85LG23, 85LG24, 85LG25, 85E23, 85GE28, 85C71, 85ME35, 85KA7, 85E2, 85N5, 85N04, 85SG2, 85E34, 85LG38, 85LG40, 85MN2, 85MD25, 85MN1.
Molybdenum Nutrition., M. M. Riley
Molybdenum Nutrition., M. M. Riley
Experimental Summaries - Plant Research
Field trials. Residual value of Molybdenum on an acid soil, 81N040. Residual value of Molybdenum on an acid soil, 81M2. Residual value of Molybdenum of an acid soil, 81LG12. Residual value of Molybdenum on an acid soil, 82N07. Residual values of different Molybdenum sources, 84Me10. Residual values of different Molybdenum sources, 84Ge49 Forms and rates of soil and seed applied Molybdenum, 84Me9. Molybdenum requirements of wheat, triticale and lupins, 84Me8. Residual values of Molybdenum with different nitrogen sources, 85M40. The Molybdenum nutrition of various crop and pasture cultivars, 85Mo42. Molybdenum with pre-emergent herbicides, 85TS21. Glasshouse experiments. Reactions of Molybdenum with …
Agronomy Of Oat Varieties., W. K. Anderson
Agronomy Of Oat Varieties., W. K. Anderson
Experimental Summaries - Plant Research
Nitrogen rates x oat varieties, 85MT47. Seed rates x oat varieties, 85MT48. Time-of-sowing x oat varieties, 85MT49. Applied Phenology in crop variety testing, 85WH5, 85N4.
Atlas Illustrating The Characteristics Of Groundwater In Nebraska, Vince Dreeszen
Atlas Illustrating The Characteristics Of Groundwater In Nebraska, Vince Dreeszen
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Changes In Forest Soils Following Clearcutting Of Pine Forests In The Ouachita Mountains Of Arkansas, Harlan R. Stoin, Bajuri Bin Kadmin, Lyell F. Thompson
Changes In Forest Soils Following Clearcutting Of Pine Forests In The Ouachita Mountains Of Arkansas, Harlan R. Stoin, Bajuri Bin Kadmin, Lyell F. Thompson
Journal of the Arkansas Academy of Science
Soil characteristics of the mineral surface soil (0-6 cm) on three small watersheds in the Ouachita Mountains of Arkansas from which the pine forests have been clearcut, crushed, and burned for site preparation were studied for the first two years following clearcutting and compared to soils from adjacent uncut pine forest watersheds. Following clearcutting and burning, soil pH was generally higher than in uncut forest soils. The greatest pH differences occurred within several months of burning and generally decreased through the end of the second year. Soil organic matter content was lower immediately following clearcutting and burning and increased to …
Mineralogy Of Kentucky Soils, Anastasios D. Karathanasis
Mineralogy Of Kentucky Soils, Anastasios D. Karathanasis
Soil Science News and Views
Very few mineralogical data have been published for soils in Kentucky. As an initial attempt to classify mineralogy of the subsoil, a general mineralogy map of the state was constructed based on currently available information (Fig. 1). The map suggests that quartz, mica, and feldspars are the dominant minerals of the sqnd and silt size fractions and that illite, smectite, kaolinite and hydroxyinterlayered vermiculite or smectite dominate the clay size soil fraction. Soils of the Western Coalfields, Eastern Coalfields, and Eastern Pennyrile regions generally contain more quartz in the sand and silt fraction than soils of the Purchase, Western Pennyrile, …
Microbial Manganese Reduction By Enrichment Cultures From Coastal Marine Sediments, David J. Burdige, Kenneth H. Nealson
Microbial Manganese Reduction By Enrichment Cultures From Coastal Marine Sediments, David J. Burdige, Kenneth H. Nealson
OES Faculty Publications
Manganese reduction was catalyzed by enrichment cultures of anaerobic bacteria obtained from coastal marine sediments. In the absence of oxygen, these enrichment cultures reduced manganates when grown on either lactate, succinate, or acetate in both sulfate-free and sulfate-containing artificial seawaters. Sodium azide as well as oxygen completely inhibited microbial manganese reduction by these enrichment cultures, whereas molybdate had no effect on them. The addition of nitrate to the medium slightly decreased the rate of Mn2+ production by these enrichment cultures. These findings are consistent with the hypothesis that the manganese-reducing organisms in these enrichment cultures use manganates as terminal …
Fault Movements And Tectonics Of Eastern Iran: Boundaries Of The Lut Plate, Ali A. Nowroozi, A. Mohajer-Ashjai
Fault Movements And Tectonics Of Eastern Iran: Boundaries Of The Lut Plate, Ali A. Nowroozi, A. Mohajer-Ashjai
OES Faculty Publications
Summary. From 1977 March 21 to 1981 July 28, about 15 earthquakes with Ms ≥6.0 and many earthquakes with Ms≥4.5 have occurred in Iran. The upsurge of seismic activity started following the Khorqu earthquake of 1977 March 21, M,=7.0, south-east of the Fars folded series of Zagros. This shock had a thrust focal mechanism solution indicating the general northward movement of the Arabian plate with respect to the Iranian landmass. It was followed by six major damaging earthquakes in eastern Iran. The earthquakes are associated with extensive faulting which surrounds the Lut plate. (1) The Zarand earthquake …
Metamorphism And Migmatization Of Metasediments In The Precambrian English River Subprovince, Western Ontario, Rodney M. Baumann
Metamorphism And Migmatization Of Metasediments In The Precambrian English River Subprovince, Western Ontario, Rodney M. Baumann
Theses and Dissertations
Metasediments of the Precambrian English River subprovince, a subdivision of the Superior province, are conspicuously migmatized by 'bands of light-colored, igneous-appearing material. The metasediments themselves consist of alternating layers of pelite and wacke lithologies, which represent original mudstones and graywackes respectively. Their deposition is thought to represent subaqueous turbidity flows.
For the metasediments of the study area, a 250 square kilometer portion of the English River subprovince, metamorphic grade increases southward from the English River subprovince's northern border. Two isograds have been mapped: the disappearance of muscovite and the disappearance of stable sillimanite. Geothermometry studies are consistent with the trend …
Middle And Late Wisconsinan (Pleistocene) Insect Assemblages From Illinois, Kristine D. Carter
Middle And Late Wisconsinan (Pleistocene) Insect Assemblages From Illinois, Kristine D. Carter
Theses and Dissertations
Two highly organic sediment sequences from central and western Illinois (the Athens North Quarry and Biggsville sites, respectively) of Middle and Late Wisconsinan age were studied to gain knowledge about the environment and climate of this area during the time immediately prior to the maximum extent of the last glaciation. Paleoenvironmental and paleoclimatic inferences are based principally upon knowledge of the habitat preferences and geographic distributions of extant species of beetles that are represented as fossils. These data are supplemented by information from sedimentological and taphonomic studies and from previously published palynological and plant-macrofossil studies.
The Athens North Quarry site …
Petrology Of The Sentinel Butte Formation (Paleocene), North Dakota, Nels F. Forsman
Petrology Of The Sentinel Butte Formation (Paleocene), North Dakota, Nels F. Forsman
Theses and Dissertations
Sedimentary materials of the Sentinel Butte Formation have been petrographically examined using optical and scanning electron micro scope/microprobe techniques. The formation consists of fine-grained materials which generally are classified mineralogically as volcanic litharenites or feldspathic litharenites. Most rock units in the formation are siltstones and mudstones. Multiple source rock types, including volcanic, metamorphic, and sedimentary, are represented by mineralogic constituents, but volcanic rock fragments are most abundant. Petrographic distinctions between basal and uppermost sandstone units suggest that a change in sediment supply took place near the end of Sentinel Butte time. Authigenic cement development appears concentrated in more porous and …