Open Access. Powered by Scholars. Published by Universities.®

Earth Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 1261 - 1279 of 1279

Full-Text Articles in Environmental Indicators and Impact Assessment

Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation Jan 1971

Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation

Publications (WR)

Progressive increases in concentration of dissolved solids in the Colorado River water from Lake Powell to Imperial Dam seem to alter plankton dynamics and biological productivity of the river. Also, changes in biological productivity and micronutrients concentrations occur within the same reservoir. Development of a digital simulation model to predict micronutrients concentrations and biological productivity is necessary for diagnosing changes in plankton population and effluent-carrying capacity of the system. The objectives of the study are: (1) to determine trace metal balance at different locations in Lake Mead, (2) to measure biological productivity and conduct plankton population counts at each sampling …


The 1963-64 Lake Mead Survey, J. M. Lara, J. I. Sanders, Bureau Of Reclamation Aug 1970

The 1963-64 Lake Mead Survey, J. M. Lara, J. I. Sanders, Bureau Of Reclamation

Publications (WR)

The 1963-64 Lake Mead survey was run to compute the reservoir capacity. Results of the geodetic and hydrographic surveys and sediment sampling equipment are described. The geodetic survey showed Hoover Dam subsided an average of 118 mm since 1935. Sonic sounding, photogrammetry, and crosssectional profiling methods were used to run the hydrographic survey. Reservoir area and capacity tables were generated using an electronic computer. The present lake capacity is 29,755,000 acre-ft and the reservoir surface area is 162,700 acres at elevation 1229 ft. 2,720,000 acre-ft of sediments accumulated in the lake since 1935. A unit weight of 60 Ib/cu ft …


How Important Is Sulphur For Pastures?, R N. Glencross, W. J. Cox Jan 1969

How Important Is Sulphur For Pastures?, R N. Glencross, W. J. Cox

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

With the introduction of low sulphur compound and concentrated fertilisers, a new look is required at the sulphur status of West Australian soils, and the sulphur requirement of pasture.

In this article the functions of sulphur, deficiency symptoms and potential problem soils are described.

Current recommendations and plans for future research work are outlined.


Land Use In The Kulin-Kondinin-Hyden District : Notes On A Recent Survey, D J. Carder Jan 1969

Land Use In The Kulin-Kondinin-Hyden District : Notes On A Recent Survey, D J. Carder

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

A RECENT survey by the Department of Agriculture's Soil Conservation Service has highlighted the nature of the problems facing farmers with flooded or salt-affected land near salt lake country in the wheatbelt.


The Ord River Regeneration Project. 2. Dealing With The Problem, K Fitzgerald Jan 1968

The Ord River Regeneration Project. 2. Dealing With The Problem, K Fitzgerald

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

THE PROGRAMME of protective and remedial work being undertaken in the Ord River catchment area had as its major objective the re-establishment of perennial vegetation, as a means of controlling erosion and reducing the silt load of the rivers. It is now in its seventh year of operation.


The Effects Of Geographical And Climatic Setting On The Economic Advantages Of Alternative Flood Control Measures, Clyde R. Dempsey, L. Douglas James Jan 1968

The Effects Of Geographical And Climatic Setting On The Economic Advantages Of Alternative Flood Control Measures, Clyde R. Dempsey, L. Douglas James

KWRRI Research Reports

It has long been realized that tributary urban development and channel improvement greatly affect the flow regime in a given watershed. A previous study used the Stanford Watershed Model to derive relationships expressing how the flood peaks in Sacramento, California, might be expected to vary with changing conditions of urbanization, channelization, and tributary drainage area. In order to observe the effects of climatic setting and geographical location on these relationships, the same type of analysis was applied to a drainage area near Louisville, Kentucky.

If reservoir storage is to be considered in a flood control program, it is necessary to …


The Ord River Catchment Regeneration Project. 1. The Nature, Extent And Causes Of Erosion In The Ord River Catchment Area, K Fitzgerald Jan 1967

The Ord River Catchment Regeneration Project. 1. The Nature, Extent And Causes Of Erosion In The Ord River Catchment Area, K Fitzgerald

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

OF the 17,800 square miles of Ord River catchment area, an estimated 1,450 square miles of country is subject to varying degrees of erosion.

This lies astride the Ord River and its major tributaries, the Elvire, Negri, Stirling, Panton, Turner, Nicholson and RB rivers.

The bulk of the eroded country lies in W.A. but part projects into the Northern Territory.


1964 Drought In Connecticut, The, Byron E. Janes, Joseph J. Brumbach Jun 1965

1964 Drought In Connecticut, The, Byron E. Janes, Joseph J. Brumbach

Storrs Agricultural Experiment Station

No abstract provided.


Water Chemistry Survey Of Boulder Basin, Lake Mead, P. R. Tramutt, Bureau Of Reclamation Jun 1965

Water Chemistry Survey Of Boulder Basin, Lake Mead, P. R. Tramutt, Bureau Of Reclamation

Publications (WR)

The survey results indicate that the impoundment of water behind Hoover Dam has not adversely affected the dissolved oxygen (DO) content and that water quality and DO content were uniform regardless of depth. The study made in April-May 1964 will provide water quality data of Lake Mead prior to releases from Lake Powell as a basis for evaluating Lake Powell's effect on water quality and limnology of Lake Mead. The performance of a DO analyzer was tested and found unsatisfactory at depths below 150 ft. Parameters tested by standard chemical analyses of water samples in the Denver Laboratory and by …


Contour Planting For Hillside Orchards. Part 1, N H. Shorter Jan 1965

Contour Planting For Hillside Orchards. Part 1, N H. Shorter

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

FRUIT growers intending to plant an orchard on sloping land, would be well advised to consider the suitability of the block for planting on a contour system.


Beach Erosion Control Study On Duval County, Fla, U.S. Army Engineer District, Jacksonville Corps Of Engineers Nov 1964

Beach Erosion Control Study On Duval County, Fla, U.S. Army Engineer District, Jacksonville Corps Of Engineers

Waterways and wildlife

The purpose of this study was to define the beach erosion and the hurricane-induced flooding problems in Duval County, to determine the most economical methods of alleviating those problems, and to determine the division of costs between the Federal Government and local interests .


A Review Of Agriculture On The Esperance Downs, J L. Shier, T. C. Dunne, E. N. Fitzpatrick Jan 1963

A Review Of Agriculture On The Esperance Downs, J L. Shier, T. C. Dunne, E. N. Fitzpatrick

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

Esperance is approaching a period of rapid development based on the results of research at Esperance Downs Research Station and on farmers' properties in the area.

This article reviews the soils, vegetation, climate, agricultural development and development costs of the area.


Interbasin Movement Of Ground Water At The Nevada Test Site, Isaac J. Winograd Mar 1962

Interbasin Movement Of Ground Water At The Nevada Test Site, Isaac J. Winograd

Publications (WR)

The present paper presents hydraulic evidence for the interbasin circulation of ground water through carbonate rocks of Paleozoic age at the Nevada Test Site. An integral part of this evidence is the discovery that aquifers in alluvium and tuff, formerly thought to be the principal aquifers at the Test Site, are semiperched above a thick tuffaceous aquiclude that separates them from the carbonate rocks.

This paper is based on one of the studies being made by the Geological
/="/">Survey for the Atomic Energy Commission. These studies seek to evaluate
/="/">the risk that may arise if ground water should …


Light Lands In Western Australia. 2. Their Nature, Distribution And Climate, George Henry Burvill Jan 1962

Light Lands In Western Australia. 2. Their Nature, Distribution And Climate, George Henry Burvill

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

LIGHT land development for agriculture is a major feature in the story of agriculture in Western Australia. Sixty years ago there was less than one million acres of arable land.

The total area planted to all crops was less than 250 thousand acres and the wheat harvest was less than one million bushels.


Loss Of Structure In Wheatbelt Soils, T C. Stoneman Jan 1962

Loss Of Structure In Wheatbelt Soils, T C. Stoneman

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

MANY of the heavy soils of the West Australian wheatbelt have been farmed for 30 or 40 years, and farmers now frequently complain that these soils are becoming more difficult to handle, that greater power is needed to break up the soil, and the time that it remains in a workable condition after rains is shorter.


Light Lands In Western Australia. 1. History And Future Prospects, F L. Shier Jan 1962

Light Lands In Western Australia. 1. History And Future Prospects, F L. Shier

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

BECAUSE of the scattered distribution of light lands of the agricultural areas of Western Australia among the better soils, and their large total area, it is not surprising that attempts to develop these unattractive soils for agriculture started many years ago.


Soil Conservation In The Kimberley Area Of Western Australia, K Fitzgerald Jan 1960

Soil Conservation In The Kimberley Area Of Western Australia, K Fitzgerald

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

OFFICERS of the Soil Conservation Branch of the West Australian Department of Agriculture, have not been engaged in soil conservation work in the Kimberleys prior to this year, not because a serious erosion problem did not exist, but rather because with limited trained staff available they were too fully occupied elsewhere.

The recent arrival of a senior Soil Conservation Officer in the area to assist and plan an approach to the problem of soil erosion in the Ord River catchment area is therefore very welcome.


Irrigation In Western Australia : Report On Government-Controlled Areas : 1958-59, H K. Gibsone Jan 1960

Irrigation In Western Australia : Report On Government-Controlled Areas : 1958-59, H K. Gibsone

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

IRRIGATION in the south-western portion of Western Australia is mainly confined to the coastal plain west of the Darling Range where the three main irrigation districts of Harvey, Collie and Waroona have been established by the State Government.

The Government-controlled irrigation areas extend southward from Waroona (70 miles from Perth) to Dardanup (120 miles from Perth) and have an average width of about five miles.


Leaflet No 1003 - The Salt Problem In The Wheat Belt, G. H. Burvill Jan 1950

Leaflet No 1003 - The Salt Problem In The Wheat Belt, G. H. Burvill

Bulletins 1 - 2999

IN the wheat belt of Western Australian bare patches in farm paddocks are often seen. Many are bare, or almost bare, because of too much salt in the soil. The excess of salt prevents the germination of seeds, or kills living plants, because it causes the water supply for germination or growth to be cut off. This salt problem is so serious in places that single farms or groups of farms have been ruined; wheat growing on them has become unprofitable.