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Tree Crops For Profit And Land Improvement, John Bartle Jan 1991

Tree Crops For Profit And Land Improvement, John Bartle

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

Western Australian agriculture is deficient in good perennial species. The traditional segregation of agriculture and forestry has diverted attention from commercial wood producing trees as a potential perennial crop. Recently, scientists have made rapid progress in developing tree cropping systems suitable for extensive use in the wetter (more than 600 mm average annual rainfall) areas of the lower south-west. There is potential for a major industry based on fast-growing eucalypts for pulpwood. The foundations for this industry developed from work on agroforestry, forestry sharefarming and salinity control.

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Deep Tillage : Keep An Eye On Costs As Well As Yields, Amir Abadi, Andrew Bathgate Jan 1991

Deep Tillage : Keep An Eye On Costs As Well As Yields, Amir Abadi, Andrew Bathgate

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

Deep tillage overcomes compaction of sandy soils caused by movement of heavy machinery. Many experiments since 1981 have shown cereal yields improve as a result of deep tillage. However, the increased yield does not necessarily mean more profit when costs are taken into account. To determine the profitability of deep tillage farmers must consider its impact on other farm operations. A whole-farm analysis is needed to accurately determine the increase in profit resulting from deep tillage

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The Tammin Alcoa Landcare Education Centre, Department Of Agriculture And Food, Western Australia Jan 1991

The Tammin Alcoa Landcare Education Centre, Department Of Agriculture And Food, Western Australia

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

The town is home of the Tanimin Alcoa Landcare Education Centre. This is an ambitious concept by the Shire of Tammin and the Tammin Action Group to use the whole shire to demonstrate land conservation practices on farms, and to show urban and other communities what Western Australia's farmers are doing to conserve the land and practise sustainable agriculture.

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Glacial Deposits, Vol. 19, 1990-1991, Department Of Geography-Geology Jan 1991

Glacial Deposits, Vol. 19, 1990-1991, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology

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A Geophysical And Geological Study Of The Farmville Triassic Basin, Charles G. James Jr. Jan 1991

A Geophysical And Geological Study Of The Farmville Triassic Basin, Charles G. James Jr.

OES Theses and Dissertations

The Farmville basin is one of many Triassic basins which are found along the eastern coast of North America, and is the largest of the central string of basins in Virginia. Meta-volcanic and metasedimentary rocks of the Chopawamsic Formation, as well as felsic intrusives are the primary lithologies surrounding the basin. A detailed gravity survey was conducted along six roads that trend approximately NW-SE, across the basin. Geologic, gravity, magnetic, and radiometric data were used to develop a kinematic model. Gravity anomalies were isolated using two-dimensional harmonic analysis methods to isolate the local, and regional anomalies. This analysis indicates that …

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Microwave Pasteurization Of Potting Mixes, Rudolph J. Eichenberger Jan 1991

Microwave Pasteurization Of Potting Mixes, Rudolph J. Eichenberger

Journal of the Arkansas Academy of Science

A study was conducted to determine if potting soils could be pasteurized with a typical 1200 watt microwave oven. Microwave radiation times varied from 0 to 6.0 minutes. Preliminary results indicated that "damping-off" diseases could be prevented in tomato seedlings with the use of potting soils pasteurized by microwaves.

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Using Viruses To Examine Soil Treatment Of Septic Tank Effluent, Mark A. Gross, Jenna Hestir, Duane C. Wolf, E. Moye Rutledge Jan 1991

Using Viruses To Examine Soil Treatment Of Septic Tank Effluent, Mark A. Gross, Jenna Hestir, Duane C. Wolf, E. Moye Rutledge

Journal of the Arkansas Academy of Science

Viral contamination of drinking water supplies due to inadequate renovation of septic tank effluent (STE) is a public health concern. The purpose of this paper is to illustrate the use of a bacteriophage to evaluate virus movement in a soil treatment system. Viruses - MS2 bacteriophage - were injected into a wastewater treatment system with soil absorption trenches and drainage tiles, and the drain tile effluent was collected and assayed for the phage. The virus suspension was assayed and a measured amount of STE and virus suspension was pumped into the system allowing for calculation of the influent virus titer. …

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Groundwater Hydrology Of A Population Of Lindera Melissifolia In Arkansas, J. Dainette Priest, Robert D. Wright Jan 1991

Groundwater Hydrology Of A Population Of Lindera Melissifolia In Arkansas, J. Dainette Priest, Robert D. Wright

Journal of the Arkansas Academy of Science

Groundwater hydrology was monitored from October through August in and around a bottomland forest pond containing Lindera melissifolia, pondberry. The study site exhibited a series of low ancient dunes and depressions, with seasonal ponds in the depressions. Ponds showed no surface inlets or outlets. Shallow wells were made and soil cores removed along a transect from the top of one dune across the pond to a lower dune. Piezometers were installed in the wells and groundwater levels monitored. Soil core samples were analyzed to determine particle size distribution at soil profile positions selected during field analysis. It was shown that …

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Determination Of Morphologic And Volumetric Change, Peyto Glacier, Alberta, 1966-1989, Peter J. Glenday Jan 1991

Determination Of Morphologic And Volumetric Change, Peyto Glacier, Alberta, 1966-1989, Peter J. Glenday

Theses and Dissertations (Comprehensive)

During the summer months of July and August 1989, approximately 23 years after a photogrammetric survey on August 22, 1966, Peyto Glacier, a glacier selected for study during the International Hydrologic Decade (IHD) 1965-74, was re-surveyed using terrestrial geodetic surveying techniques. The volumetric and morphologic change of Peyto Glacier, Alberta from 1966 to 1989 is estimated through a combined application of digital cartometry, digital geodetic survey and Triangulated Irregular Network (TIN) digital terrain modeling and analysis. Changes in glacial volume, areal extent, teriminus position, percentage basin glaciation, slope, and aspect for the 23 year interval are shown. Additionally, a 1:10000 …

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An Introduction To The Soils Of The Narrogin Advisory District, T C. Stoneman, Department Of Agriculture And Food, National Soil Conservation Program (Australia) Jan 1991

An Introduction To The Soils Of The Narrogin Advisory District, T C. Stoneman, Department Of Agriculture And Food, National Soil Conservation Program (Australia)

Bulletins 4000 -

Descriptions, illustrations and notes on eight common soils / compiled by T.C. Stoneman.

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An Introduction To The Soils Of The Katanning Advisory District, T C. Stoneman, National Soil Conservation Program (Australia) Jan 1991

An Introduction To The Soils Of The Katanning Advisory District, T C. Stoneman, National Soil Conservation Program (Australia)

Bulletins 4000 -

With descriptions, illustrations and notes on eight common soils.

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Quaternary Geology Of The Northern Great Plains, William J. Wayne, James S. Aber, Sherry S. Agard, Robert N. Bergantino, John P. Bluemle, Donald A. Coates, Maurice E. Cooley, Richard F. Madole, James E. Martin, Brainerd Mears Jr, Roger B. Morrison, Wayne M. Sutherland Jan 1991

Quaternary Geology Of The Northern Great Plains, William J. Wayne, James S. Aber, Sherry S. Agard, Robert N. Bergantino, John P. Bluemle, Donald A. Coates, Maurice E. Cooley, Richard F. Madole, James E. Martin, Brainerd Mears Jr, Roger B. Morrison, Wayne M. Sutherland

Department of Earth and Atmospheric Sciences: Faculty Publications

The Great Plains physiographic province lies east of the Rocky Mountains and extends from southern Alberta and Saskatchewan nearly to the United States-Mexico border. This chapter covers only the northern part of the unglaciated portion of this huge region, from Oklahoma almost to the United StatesCanada border, a portion that herein will be referred to simply as the Northern Great Plains (Fig. 1). This region is in the rain shadow of the Rocky Mountains. Isoheyets are roughly longitudinal, and mean annual precipitation decreases from about 750 mm at the southeastern margin to less than 380 mm in the western and …

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Narrow-Winged Seeder Points Reduce Water Erosion And Maintain Crop Yields, Kevin Bligh Jan 1991

Narrow-Winged Seeder Points Reduce Water Erosion And Maintain Crop Yields, Kevin Bligh

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

Sowing crops without loosening the topsoil by tillage reduces water erosion. It can increase infiltration of rainfall into loamy soils, thereby reducing runoff and increasing potential crop yields. Crop yields were maintained after I1 seasons of seeding an Avon Valley loam near Beverley with minimum and no-tillage seeding operations. Infiltration increased significantly from 80 per cent of the 1983 growing-season rainfall under the traditional three tillage operations, to 87per cent under a single tillage operation using a combine seed drill. Infiltration increased further to 96 per cent under a no-tillage system using a triple^lisc drill. At Gnowangerup, 80 per cent …

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1991 Nebraska Water Conference, The Rivers Of Nebraska: Character, Conflicts And Cooperation, Ray Bentall Jan 1991

1991 Nebraska Water Conference, The Rivers Of Nebraska: Character, Conflicts And Cooperation, Ray Bentall

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Ice-Wedge Casts Of Wisconsinan Age In Eastern Nebraska, William J. Wayne Jan 1991

Ice-Wedge Casts Of Wisconsinan Age In Eastern Nebraska, William J. Wayne

Department of Earth and Atmospheric Sciences: Faculty Publications

Sand-filled, wedge-shaped structures beneath a thin layer of aeolian sand penetrate a preIllinoian till and gravel in northeastern Nebraska. Interpreted to be relic thermal contraction crack wedges, they provide the first definite evidence in this State of the former presence of permafrost. The wedges are 5- 7 m apart, 1.8-2.8 m deep and 0.6-0.9 m across at the top, taper downward to a crack and intersect to form polygons. They are filled with medium sand that contains mostly rounded and frosted grains. Vertical fabric is present in each wedge. Ventifacts lie along the top of the till, which is covered …

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Evolution Of The Aeluroid Camivora: Viverrid Affinities Of The Miocene Camivoran Herpestides, Robert M. Hunt Jr. Jan 1991

Evolution Of The Aeluroid Camivora: Viverrid Affinities Of The Miocene Camivoran Herpestides, Robert M. Hunt Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

Although the time of origin of viverrid and hyaenid carnivorans has not been clearly documented in the fossil record, their theater of evolution has long been established by a mid-Cenozoic fossil distribution entirely confined to the Old World. Recent examination of the basicranial morphology of important early aeluroid crania from Europe and Asia significantly alters earlier views of viverrid and hyaenid origins. The early Miocene carnivoran Herpestides antiquus, considered a potential ancestral hyaenid or herpestid in earlier studies, is identified as a true viverrid on the basis of a large sample of skulls of both juveniles and adults from …

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Evolution Of The Aeluroid Camivora: Hyaenid Affinities Of The Miocene Camivoran Tungurictis Spocki From Inner Mongolia, Robert M. Hunt Jr., Nikos Solounias Jan 1991

Evolution Of The Aeluroid Camivora: Hyaenid Affinities Of The Miocene Camivoran Tungurictis Spocki From Inner Mongolia, Robert M. Hunt Jr., Nikos Solounias

Department of Earth and Atmospheric Sciences: Faculty Publications

Among the mammalian fossils discovered in were crania and mandibles of rare carnivorans, 1930 by the Central Asiatic Expedition of the including the first complete skulls of several Asian American Museum of Natural History (New York) mid-Miocene lineages. Most of these fossils came in the Tung Gur Formation of Inner Mongolia from a single locality termed Wolf Camp Quarry that produced, among other striking finds, a small fox-sized cranium referred to a new genus and species Tungurictis spocki Colbert 1939. Today this remains the only known cranium of Tungurictis yet discovered. Preparation and reinterpretation of the auditory region demonstrate that …

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Nebraska Mineral Operations Review, 1990, Raymond R. Burchett, Duane A. Eversoll Jan 1991

Nebraska Mineral Operations Review, 1990, Raymond R. Burchett, Duane A. Eversoll

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Conservation And Survey Division, 1991. Annual Outflow/Inflow Of Water From Nebraska, 1950-1990, Conservation Survey Divis Jan 1991

Conservation And Survey Division, 1991. Annual Outflow/Inflow Of Water From Nebraska, 1950-1990, Conservation Survey Divis

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Development Of A Land Cover Characteristics Data Base For The Conterminous U.S., Thomas R. Loveland, James W. Merchant, Donald O. Ohlen, Jesslyn F. Brown Jan 1991

Development Of A Land Cover Characteristics Data Base For The Conterminous U.S., Thomas R. Loveland, James W. Merchant, Donald O. Ohlen, Jesslyn F. Brown

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Annual Report Of Nebraska-1991, Eileen K. Peterson, Raymond R. Burchett Jan 1991

Annual Report Of Nebraska-1991, Eileen K. Peterson, Raymond R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Thurston County Test Hole Logs, Raymond R. Burchett, Frank A. Smith Jan 1991

Thurston County Test Hole Logs, Raymond R. Burchett, Frank A. Smith

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Resource News-November/December 1991 Jan 1991

Resource News-November/December 1991

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Cement Operations In Nebraska, R. R. Burchett Jan 1991

Cement Operations In Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Ocher Deposits In Nebraska, R. R. Burchett Jan 1991

Ocher Deposits In Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Peat Deposits In Nebraska, R. R. Burchett Jan 1991

Peat Deposits In Nebraska, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Composite Section Of Outcropping Rocks Along The Missouri River, R. R. Burchett Jan 1991

Composite Section Of Outcropping Rocks Along The Missouri River, R. R. Burchett

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

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Reservoir Sedimentation Studies, D C. Boudurant, R H. Livesey Jan 1991

Reservoir Sedimentation Studies, D C. Boudurant, R H. Livesey

United States Army Corps of Engineers, Omaha District

It must be recognized that, when a reservoir is constructed on a stream, all or most of the sediment transported into the reservoir by the stream will be deposited there. With few exceptions, there is no practical method for reducing or eliminating the sediment inflow; thus it is necessary to anticipate and to provide for resulting problems. The major problem is, of course, the accumulative loss of storage capacity. Other items of importance include the distribution of the sediment with respect to various storage increments, the effect on the chemical or physical quality of the water, ecological effects, and the …

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Early Eocene Biotic And Climatic Change In Interior Western North America, Scott L. Wing, Thomas M. Bown, John D. Obradovich Jan 1991

Early Eocene Biotic And Climatic Change In Interior Western North America, Scott L. Wing, Thomas M. Bown, John D. Obradovich

United States Geological Survey: Staff Publications

Imprecise correlation of the marine and terrestrial fossil records has been a major obstacle to understanding migration and extinction of continental biotas and early Cenozoic climate change

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Additional Fossil Evidence On The Differentiation Of The Earliest Euprimates, Kenneth D. Rose, Thomas M. Bown Jan 1991

Additional Fossil Evidence On The Differentiation Of The Earliest Euprimates, Kenneth D. Rose, Thomas M. Bown

United States Geological Survey: Staff Publications

Several well-preserved jaws of the rare North American omomyid primate Steinius vespertinus, including the first known antemolar dentitions, have been discovered in 1989 and 1990 in the early Eocene Willwood Formation of the Bighorn Basin, Wyoming. They indicate that its dental formula is as primitive as those in early Eocene Donrussellia (Adapidae) and Teilhardina (Omomyidae) - widely considered to be the most primitive known euprimates - and that in various dental characters Steinius is as primitive or more so than Teilhardina. Therefore, despite its occurrence at least 2 million years later than Teilhardina, S. vespertinus is the …

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