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Full-Text Articles in Physical Sciences and Mathematics

Selenium In Nebraska's Groundwater And Streams, R.A. Engberg Dec 1973

Selenium In Nebraska's Groundwater And Streams, R.A. Engberg

Conservation and Survey Division

No abstract provided.


Preliminary Reconnaissance Water Quality Survey Of The Buffalo National River, R. E. Babcock, H. C. Macdonald, E. E. Dale Jr., R. L. Meyer, Joe Nix, D. G. Parker, Eugene Schmitz Oct 1973

Preliminary Reconnaissance Water Quality Survey Of The Buffalo National River, R. E. Babcock, H. C. Macdonald, E. E. Dale Jr., R. L. Meyer, Joe Nix, D. G. Parker, Eugene Schmitz

Technical Reports

In accordance with Contract No. CX 700030105, dated 12 February 1973, the University of Arkansas , Water Resources Resear ch Center is submitting a "Preliminary Reconnaissance Water Quality Survey of the Buffalo National River." The Water Resources Research Center of Arkansas has supplied the necessary personnel and facil ities to perform a preliminary reconnaissance survey of the Buffalo National River of Arkansas with special emphasis placed on the establishment of both permanent and temporary benchmarks for water quality sampling. Preliminary water quality samples have been collected to make those chemical, physical, and biological analyses as defined by Mr . Roland …


1972 Progress Report: Soil As A Factor In Modelling The Phosphorus Cycle In The Desert Ecosystem, J. J. Jurinak, R. A. Griffin May 1973

1972 Progress Report: Soil As A Factor In Modelling The Phosphorus Cycle In The Desert Ecosystem, J. J. Jurinak, R. A. Griffin

Elusive Documents

The research conducted in 1972 emphasized a nutrient assay of soil from the Curlew Valley site, phosphorus inventory of the vegetation and rabbit droppings, and further chemical characterization of soil phosphorus, which also included determination of the kinetics and energetics of the calcium carbonate-phosphate system.


A Measure Of The Amount Of Phosphate Adsorption And The Rate Of Release Of Indigenous Phosphate From A Desert Soil, Robert Lindsey Evans May 1973

A Measure Of The Amount Of Phosphate Adsorption And The Rate Of Release Of Indigenous Phosphate From A Desert Soil, Robert Lindsey Evans

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The capacity of a calcareous desert soil, Thiokol silt loam, to retain natural, as well as added, orthophosphate-P was measured by equilibrium adsorption employing a batch technique and evaluated using the two-slope Langmuir adsorption isotherm. From these data, corrected to account for indigenous soil P, a hypothesis was formulated as to the nature of retention of P by the soil, including the identification of two interfacial reactions involving P, and a value calculated for the adsorption maximum as defined by the Langmuir isotherm equation for P with soil at each of two soil depths and three constant temperatures within the …


An Intensive Edaphological Characterization Of The Soils Of Malambito Experimental Station And Its Implications In Future Agricultural Research, William L. Rubink May 1973

An Intensive Edaphological Characterization Of The Soils Of Malambito Experimental Station And Its Implications In Future Agricultural Research, William L. Rubink

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Malambito Experiment Station, in the Atlántico III project area, Department of Atlántico, Colombia, had almost no quantitative edaphological data on which to base agricultural research. Unexplainably low general yields as well as problem areas of deficient plant growth only confounded the results of field plot experiments. Intensive soil sampling and subsequent measurements of pH, ECe of the saturation extract, and the four major cations disproved the previous suggestions that the crop growth problems were related to saline, sodic, or degraded soil conditions. The Ca/Mg+K+Na ratio, although significant when correlated with plant height, was sufficient explanation for only a small …


Bromegrass Productivity In Relation To Precipitation, Shrub Canopy Cover And Soil Nitrogen Content, Lawrence G. Kline May 1973

Bromegrass Productivity In Relation To Precipitation, Shrub Canopy Cover And Soil Nitrogen Content, Lawrence G. Kline

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In seasons of above normal precipitation, populations of annual weedy species increase in great abundance in semi-arid desert plant communities. These increases in biomass tie up a considerable portion of the available nitrogen of such ecosystems and may depress subsequent annual grass germination.

A big sagebrush-annual bromegrass plant community was irrigated to simulate a spring growth period of abundant precipitation amenable to annual bromegras s productivity. Productivity and nitrogen content parameters were monitored throughout the spring and summer to evaluate the short and potential long term effects of this seasonal increase in "precipitation".

Irrigation increased annual bromegrass productivity almost 50 …


Groundwater Levels In Nebraska, 1972, M.J. Ellis May 1973

Groundwater Levels In Nebraska, 1972, M.J. Ellis

Conservation and Survey Division

No abstract provided.


Soil Structure Changes Under Wheatbelt Farming Systems, T C. Stoneman Jan 1973

Soil Structure Changes Under Wheatbelt Farming Systems, T C. Stoneman

Journal of the Department of Agriculture, Western Australia, Series 4

A review of 14 years of Department of Agriculture research into the effects of wheatbelt fanning practices on soil structure reaches the general conclusion that cultivation and grazing practices influence soil structure, and that structure can be improved by soil amendments and pasture growth.

Little data has been obtained to relate plant growth to improved soil structure, as measured.


1973 Seasonal Results Phosphorus And Sulphur Group, J W. Bowden Jan 1973

1973 Seasonal Results Phosphorus And Sulphur Group, J W. Bowden

Experimental Summaries - Plant Research

Summary of 1973 Seasonal results phosphorus and sulphur group. Stocking rate x super rate Residual value of superphosphate - 1972 'Decide' Maintenance assessments PXS trials Rates of super on pasture - CSIRO/NSFP Rate/super on wheat - Sources of sulphur - Gyplap - Bunbury - Lake Grace Lime Trials - Lake Jasper - Northcliffe

62MB9, 65N5, 65A1, 65C5, 65A166M30, 66ME3, 66NO7, 66LG1, 66NA3, 67NO5, 67NO5, 67GE2, 67NO11,68AL36, 68B1, 68BR5, 68BR6, 68B1, 68BR7, 68BU2, 68NO5, 69AL2, 69AL3, 69E6, 69WH15, 72M034, 72M042, 72NA35, 72NA39, 72N40, 72N037, 72N040, 72M043, 72N057, 72NO57, 72BA33, 73BA16, 73BY10, 73BY11, 73BY12, 73BY13, 73LG3/3A, 73MA9, 73MA10, 73MA12, 73MA13, 73MA14.


Progress And Data February 1973, D Tennant Jan 1973

Progress And Data February 1973, D Tennant

Experimental Summaries - Plant Research

This report summarizes progress and data available for the following investigations. Lupin Growth Analysis, Rape Growth Analysis, Fallow Re-assessment, 72M29 Wheat Variety - Root Growth Study,


Progress And Data Available For Investigations, D Tennant Jan 1973

Progress And Data Available For Investigations, D Tennant

Experimental Summaries - Plant Research

This report summarises progress and data available for the following investigations. 1. Fallow Re-assessment. 2. Root Penetration and Distribution in Wheat. 3. Moisture use by Lupins, Rape and Wheat. 4. Variety Investigations in respect of Root Growth. 72M29, 72MO41,


Summary Of 1973 Field Experiments With Advisers, M L. Poole Jan 1973

Summary Of 1973 Field Experiments With Advisers, M L. Poole

Experimental Summaries - Plant Research

SECTION I: Effect of times of planting x Benlate seed treatment on incidence of blackleg in Span and Zephyr rapeseed. SECTION II: Rapeseed Variety Trials 1973 including times of planting. This report provides a record of two series of trials carried out in 1973. Trials - 73A4, 73AL10, 73AL11, 73AL12, 73BR9, 73BR12, 73BR13, 73ES7, 73ES8, 73GE3, 73JE4, 73JE5, 73KA3, 73KA7, 73M2, 73MO11, 73MO13, 73MT5, 73MT6, 73NA6, 73NA7. Effect of times of planting x Benlate seed treatment on incidence of blackleg in Span and Zephyr rapeseed, series of 12 trials were set up, mainly in the southern agricultural areas, near previous …


Summary Of 1972 Seasonal Results "Decide" Superphosphate Rates On Pastures, J. W. Bowden Jan 1973

Summary Of 1972 Seasonal Results "Decide" Superphosphate Rates On Pastures, J. W. Bowden

Experimental Summaries - Plant Research

A total of 53 pasture trials were topdressed. Of these, 37 trials were quantitatively assessed at different times during the growing season. Of the 15 wheat trials sown, only four trials gave useful results because of multiple drilling techniques used on most trials. Until the trial results have undergone comprehensive statistical analysis, no conclusions can be drawn. about the levels of response or "optimum" rates of superphosphate application at individual sites. However, because of the very short growing season in 1972 responses were generally poor. It appears that nil superphosphate application would have been optimum for animal production in the …


Lupin Split Seed Pilot Trial - Esperance Downs Research Station., J. W. Gartrell Jan 1973

Lupin Split Seed Pilot Trial - Esperance Downs Research Station., J. W. Gartrell

Experimental Summaries - Plant Research

Lupin Split Seed Pilot Trial. Esperance Research Station 1974. % of seed classed according to size and degree of splitting. Manganese - S Richardson - Dandaragan 73PE2


Summary Of Trial Results - 1973, N. R. Mckeown Jan 1973

Summary Of Trial Results - 1973, N. R. Mckeown

Experimental Summaries - Plant Research

Trials in Progress During 1973 observations were made on 11 small plot legume species· trials and 11 grazing trials. In 1974 the small plot trials will remain the same and the grazing trials will be reduced to 8. This report summarizes the results from the grazing trials under the following headings:- Seasonal Conditions. Grazing Experiments. 68M023 - Legume Grazing Management·Trial,. West Moora. 71LG17 - Comparison of Production from Cyprus Medic and Volunteer Pasture. Comparison of Production from Tornafield Medic, Serradella and Subterranean.Clover. 70ME2 - Walgoolan 71WH13 - Wongan Hills 69M017 - Watheroo 69LG24 - Lake Grace. Low Oestrogen Legume Grazing …


1973_Pasture Species Investigations - Wheatbelt, N. R. Mckeown Jan 1973

1973_Pasture Species Investigations - Wheatbelt, N. R. Mckeown

Experimental Summaries - Plant Research

Results from trials comparing the growth and persistence of a number of annual pasture legumes in 1973 are presented in this report. Rainfall conditions during the year are described briefly and a table of annual and growing season rainfall at relevant centres is appended. The experiments are grouped as follows according to average annual rainfall:- Zone A - Average annual rainfall 400 mm. Zone B - Average annual rainfall 345 - 400 mm. Zone C - Average annual rainfall 345 mm. and then further on soil type. 70GE4, 70ME3, 70ME4, 70NA3, 70TS2, 70TS5, 71LG16, 71TS22, 72LG3, 72LG26,


1973 Rates Of Phosphate On Lupin Yield, G Walton Jan 1973

1973 Rates Of Phosphate On Lupin Yield, G Walton

Experimental Summaries - Plant Research

Comments on Results - New Land sites (Graphs 1, 2) - The three sites were very responsive with the point of inflexion about 600 kg/ha super rate (similar to 1972 result). The seed x super rate interaction shows the quicker response to super with higher seeding rates. Low Super Bank (800 kg/ha) (GRAPH 3) - The two sites showed very little response to super applied. On the Eradu sandplain no response to super for either Unicrop or Wheat. On the Watheroo yellow sandplain (73M015) the two lupin cultivers and the wheat gave different responses. High Super Bank (>1 OOOkg/ha) …


1973 Long Term Rotation Trials, Ian Rowland Jan 1973

1973 Long Term Rotation Trials, Ian Rowland

Experimental Summaries - Plant Research

The results shown are the yield of grain harvested from crops grown after various lengths of pasture ley. Experiments - W56H, 66M29, 67BA6, 68E5, 68SG5, 69GE20,


1973 Rates Of Phosphate On Lupin Yield, G Walton Jan 1973

1973 Rates Of Phosphate On Lupin Yield, G Walton

Experimental Summaries - Plant Research

Comments on results New land sites (Graphs 1 & 2) The three sites were very responsive with the point of inflexion about 600 kg/ha super rate (similar to 1972 result). The seed x super rate interaction shows the quicker response to super with .higher seeding rates. Low super bank (800 kg/ha) (GRAPH 3) The two sites showed very little response to super applied. On the Eradu sandplain no response to super for either Unicrop or Wheat. On the Watheroo yellow sandplain ( 73M015) the two lupin cultivers and the wheat gave different responses. High super bank ( >1 OOOkg/ha) (GRAPH …


1973 Time Of Planting And Rate Of Seeding On Lupin Yield, G Walton Jan 1973

1973 Time Of Planting And Rate Of Seeding On Lupin Yield, G Walton

Experimental Summaries - Plant Research

Of the four time of planting trials two definitely showed superiority of earlier seeding (73BA5, 73E6). The two trials in the Southwest (73BR14 and 73MT7) gave highest yields with June sowing compared to May. Three trials (73BR14, 73E6 and 73BA5) appear to have a Variety x Time interaction for plant density, but no definite trend for either Uniharvest or Unicrop although later sowing reduced plant density. Seeding rates in excess of 82 kg/ha gave the highest yields in all trials. The rate of seeding experiments (73BA5 and 73MT7) show that the best crop density for yield (graph) lies between 8 …


1973 Lupin Cultivar Comparison, G Walton Jan 1973

1973 Lupin Cultivar Comparison, G Walton

Experimental Summaries - Plant Research

Comparison of lupin varieties - 73LG6, 73LG7, 73LG78, 73A15, 73BA6, 73C3, 73MT8, 73MT20, 73N3.


Topographic Regions Map Jan 1973

Topographic Regions Map

Conservation and Survey Division

No abstract provided.


Nebraska Groundwater Level (Decline & Rise), 1973 Jan 1973

Nebraska Groundwater Level (Decline & Rise), 1973

Conservation and Survey Division

No abstract provided.


Total Number Of Irrigation Wells Located In Nebraska Counties As Of 1973 Jan 1973

Total Number Of Irrigation Wells Located In Nebraska Counties As Of 1973

Conservation and Survey Division

No abstract provided.


The Soil Conservation Service : Its Basis Of Co-Operation With Landowners, G W. Spencer, J. E. Watson Jan 1973

The Soil Conservation Service : Its Basis Of Co-Operation With Landowners, G W. Spencer, J. E. Watson

Journal of the Department of Agriculture, Western Australia, Series 4

The Soil Conservation Act of 1945 set up within the Department of Agriculture a Soil Conservation Service under the control of a Commissioner of Soil Conservation.

The Service aims to promote types of land use which will conserve the soil and prevent or overcome soil erosion. It also aims to educate landholders and the public generally in the aims and practice of soil conservation.

This article relates mainly to farm land activities, and in particular the co-operation of the Service with individual primary producer landholders for the prevention and control of erosion on their land.


Broad Spectrum Microwave Systems For Remotely Measuring Soil Moisture Content, W. P. Waite, K. R. Cook, B. B. Bryan Jan 1973

Broad Spectrum Microwave Systems For Remotely Measuring Soil Moisture Content, W. P. Waite, K. R. Cook, B. B. Bryan

Technical Reports

A theoretical and experimental study of the microwave reflectivity of soils with varying moisture content was conducted. A system was developed to measure reflectivity over a continuous frequency range of 4 to 26.5 GHz, at incidence angles from 10° to 70°, and with both horizontal and vertical polarization. The measurements were found to be extremely accurate for smooth homogeneous surfaces, however, the effects of surface roughness were found to be more severe than predicted due to the discontinuous nature of naturally occurring rough surfaces. An algorithm was developed which used the frequency dependence of the reflectivity to estimate the effective …


1973 Pasture Species Investigations - High Rainfall Area, D. A. Nicholas Jan 1973

1973 Pasture Species Investigations - High Rainfall Area, D. A. Nicholas

Experimental Summaries - Plant Research

1. Clover cultivar grazing trial - North Bannister 2. Clover cultivar grazing trial - Chowerup 3. Pasture types x stocking rate trial - Denmark Research Station 4. Low oestrogen clover cultivar trial - Mobrup 5. Stocking rate and conservation for steer beef production - Mt. Barker Research Station. 6. Perennial versus annual grass grazing trial – Manjimup Research Station. 68NA1, 701BR15, 72D1, 68BR27, 71MTT46, 72MN5,


1973 Legume Seed Inoculation, D L. Chatel Jan 1973

1973 Legume Seed Inoculation, D L. Chatel

Experimental Summaries - Plant Research

Lupin Experiments - Eleven trials were sown during 1973 with the aim of further examining the response of lupins to inoculation on old clover land, new to lupins, and some on new land. The lime pellet and gum slurry methods were compared. The opportunity was also taken to compare a new rhizobia, WU8, with the current commercial inoculant WU425. 1. Inoculation of Uniharvest lupins - time of sowing, strain of rhizobia and method of inoculation. Sown as second crop on old clover land - WILLIAMS. 2. Inoculation of Uniharvest lupins sown as a first crop on old clover land - …


Time Of Planting And Rate Of Seeding On Lupin Yield, G Walton Jan 1973

Time Of Planting And Rate Of Seeding On Lupin Yield, G Walton

Experimental Summaries - Plant Research

Of the four time of planting trials twodefinitely showed superiority of earlier seeding (73BA5, 73E6). The two trials in the Southwest (73BR14 and 73MT7) gave highest yields with June sowing compared to May. Three trials (73BR14, 73E6 and 73BA5) appear to have a Variety x Time interaction for plant density, but no definite trend for either Uniharvest or Unicrop although later sowing reduced plant density. Seeding rates in excess of 82 kg/ha gave the highest yields in all trials. The rate of seeding experiments (73BA5 and 73MT7) show that the best crop density for yield (graph) lies between 8 and …


The Pierre-Niobrara Unconformity In Western Nebraska, Harold M. Degraw Jan 1973

The Pierre-Niobrara Unconformity In Western Nebraska, Harold M. Degraw

Conservation and Survey Division

The Pierre-Niobrara unconformity, one of several significant unconformities in the Cretaceous System of the Western Interior region, has not generally been recognized. Detailed correlation of electric logs of a large number of wells in western Nebraska provides evidence of its existence. Isopach maps of the beds occupying three identifiable stratigraphic intervals - a redefined Niobrara Formation, an unnamed uppermost Niobrara unit, and an unnamed basal Pierre unit, which includes the Ardmore Bentonite - provide recognizable geologic patterns that permit reconstruction of the stages of development of the unconformity. The upper part of the Niobrara Formation has been truncated in several …