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Articles 1531 - 1560 of 1603

Full-Text Articles in Environmental Indicators and Impact Assessment

Bulletin 3992 - Nitrogenous Fertilisers For Cereal Production, M. G. Mason Apr 1979

Bulletin 3992 - Nitrogenous Fertilisers For Cereal Production, M. G. Mason

Bulletins - 3000 - 3999

Because fertiliser prices continue to rise, it is becoming increasingly important to understand what affects the response to fertilisers by crops.

Among the many factors influencing crop response to nitrogen applications, the most important are the season, soil type, paddock history, time of application and source of nitrogen. Before deciding whether to use nitrogen on a cereal crop, which source to use and at what rate, the farmer needs some understanding of how these factors work.


Erosion Risks With High Stocking Rates At Kojonup Trial, Department Of Agriculture, Western Australia Jan 1979

Erosion Risks With High Stocking Rates At Kojonup Trial, Department Of Agriculture, Western Australia

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

A pasture grazing trial at Kojonup dramatically illustrated the effects of Cyclone Alby. Severe erosion was evident on the heavily stocked plots while the more lightly stocked plots showed little damage.


Contour Cultivation : Cheap Erosion Control, T R. Negus, B. Barrett Jan 1979

Contour Cultivation : Cheap Erosion Control, T R. Negus, B. Barrett

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

Although the benefits of contour cultivation are well recognised, it makes cultivation more difficult, particularly if the paddock is split by contour banks and grassed waterways. However, a comparison east of Pingelly indicates that contour cultivation is little more expensive or time-consuming than ordinary cultivation.


Potential Use Of Hydroelectric Facilities For Manipulating The Fertility Of Lake Mead, Larry J. Paulson, John R. Baker, James E. Deacon Jan 1979

Potential Use Of Hydroelectric Facilities For Manipulating The Fertility Of Lake Mead, Larry J. Paulson, John R. Baker, James E. Deacon

Publications (WR)

Analysis of historical nutrient data for Lake Mead indicates that the fertility of the reservoir has decreased which may be the cause for a corresponding decline in the largemouth bass population. However, it appears that fertility can be manipulated by altering the operation of the dam. The depletion of nutrients in the euphotic zone by phytoplankton and subsequent accumulation in the hypolimnion during summer and fall provide a natural nutrient gradient from which water of varying fertility can be drawn for discharge. This combined with alterations in the depth or seasonal pattern of discharge can possibly be used to enhance …


"Toxic Chemicals In The Environment", William E. Cooper Jun 1978

"Toxic Chemicals In The Environment", William E. Cooper

Special Collections: Oregon Public Speakers

Presented and recorded with Arbib, M. A., "Environmental Simulation and Long-Term Planning."


Fisheries Report No 35 - Fish And Exploited Crustaceans Of The Swan-Canning Estuary, R C.J. Lenanton Jan 1978

Fisheries Report No 35 - Fish And Exploited Crustaceans Of The Swan-Canning Estuary, R C.J. Lenanton

Fisheries Research Reports

Fishes of the Swan-Canning estuarine system are typical of those found in other lower west coast estuarine systems of Western Australia. Species representing three families of elasmobranchs, several of which are commercially important, twenty families of teleosts, and two families of crustaceans (Table 1) commonly occur in this estuarine system. The many other species which occur less commonly in the Swan- Canning estuary are mostly members of the additional families listed in Table l.

The information contained in this document was made available for use by the authors of the following two publications : -

Forbes and Fitzkardinge (1977) Swan …


Fisheries Report No 36 - Utilization Of The Bunbury And Geographe Bay Marine Resource By Professional And Amateur Fishermen, Michael H. Walker Jan 1978

Fisheries Report No 36 - Utilization Of The Bunbury And Geographe Bay Marine Resource By Professional And Amateur Fishermen, Michael H. Walker

Fisheries Research Reports

Utilization of the Bunbury and Geographe Bay marine resource by professional and amateur fishermen was investigated by personal interview, distribution and analysis of research log sheets, and examination of commercial statistics for the area, published by the Australian Bureau of Statistics.

Total professional production for the years 1966/67 - 1974/75 for Geographe Bay varied between 225517 and 1218049 Kg (mean 497175) with a mean annual value to fishermen of $427708. Production for the Bunbury marine area varied between 157666 and 333810 Kg (mean 226526) with a mean value to fishermen of $311008. For the 1975/76 season the total production was …


Fish Of Lake Mead And Lake Mohave, Robert C. Allan, Dennis L. Roden Jan 1978

Fish Of Lake Mead And Lake Mohave, Robert C. Allan, Dennis L. Roden

Publications (WR)

This publication offers an in-depth study of the fish and other organisms that live in Lakes Mead and Mohave. The history and background of the two lakes is offered, as well as information about diseases, parasites, and unusual fish occurrences. Food sources, predation and competition are also discussed.


The Effects Of Sulphur Dioxide On Selected Hepatics, Steven L. Gatchel Jan 1978

The Effects Of Sulphur Dioxide On Selected Hepatics, Steven L. Gatchel

Masters Theses

Extensive studies have been reported on the air pollutant sulphur dioxide (SO2), and its effects on vascular and nonvascular plants. It has been shown to interrupt normal physiology, metabolism, reproduction, and alter the plant’s morphology.

Of the cryptogams, lichens have been extensively used as biological indicators of air pollution. More recently, bryophytes have been shown to be as sensitive to contaminates as lichens, and may exhibit responses to the pollutant similar to those of vascular and nonvascular plants. The threshold sensitivity of these cryptogams is about 0.5 ppm over a 12 hour period. However no study to date …


Limnological Aspects Of Lake Mead, Nevada-Arizona, John R. Baker, James E. Deacon, Thomas A. Burke, Samuel S. Egdorf, Larry J. Paulson, Richard W. Tew, Bureau Of Reclamation Jun 1977

Limnological Aspects Of Lake Mead, Nevada-Arizona, John R. Baker, James E. Deacon, Thomas A. Burke, Samuel S. Egdorf, Larry J. Paulson, Richard W. Tew, Bureau Of Reclamation

Publications (WR)

Lake Mead is a deep, subtropical, moderately productive, desert impoundment with a negative heterograde oxygen profile occurring during; the summer stratification. investigations of the Boulder Basin of Lake Mead by the University of Nevada were initiated in November 1971. The primary objective of the study was to determine what effects industrial and sewage effluent from the Las Vegas metropolitan area, discharged into Las Vegas Bay, have had on the water quality and limnological conditions of Boulder Basin. Data from the 1975-76 period are presented in detail, with earlier data included in the summaries and discussions. Measurements of water temperature, dissolved …


The Limnetic Zooplankton Community Of Boulder Basin, Lake Mead In Relation To The Metalimnetic Oxygen Minimum, Thomas A. Burke Apr 1977

The Limnetic Zooplankton Community Of Boulder Basin, Lake Mead In Relation To The Metalimnetic Oxygen Minimum, Thomas A. Burke

Publications (WR)

The limnetic zooplankton community of Boulder Basin, Lake Mead, was examined to determine the role of this community in the development of a metalimnetic oxygen minimum which regularly occurs in the lake. Analysis of the community from May 1975 to April 1976 revealed that zooplankton maintain high populations within the metalimnion during summer stratification. The species composition of the community changes noticeably during the summer, but due to advanced stages excysting from resting forms, a complete assemblage of individuals are found throughout the 74 day period studied. Thermal stratification was weak, covering a 30 meter metalimnion. Eddy currents powered by …


Fisheries Report No 20 - Trawl Caught Fish And Crustaceans From Cockburn Sound, J. W. Penn Jan 1977

Fisheries Report No 20 - Trawl Caught Fish And Crustaceans From Cockburn Sound, J. W. Penn

Fisheries Research Reports

Cockburn Sound is one of the few sheltered embayments near the Perth metropolitan area and as such has been subjected to increasing usage by both the general public and industry. Historically the Sound has been a major commercial fishing area from which much of the fresh fish for the metropolitan area has been caught. More recently, as well as providing a significant commercial catch, a major sport fishery has developed in the area.

The first commercial trawling operations in Cockburn Sound were undertaken in the early part of this century when horses were used to tow small nets on the …


A Stream Survey Of Riley Creek, Coles County, Illinois, Using Macroinvertebrates As Indicators Of Organic Pollution, Joseph R. Rowe Jan 1977

A Stream Survey Of Riley Creek, Coles County, Illinois, Using Macroinvertebrates As Indicators Of Organic Pollution, Joseph R. Rowe

Masters Theses

A stream survey of Riley Creek in Coles County Illinois, was undertaken to determine ecological trends and the qualitative status of the aquatic community throughout the course of the stream.

The survey encompassed the entire length of Riley Creek from the area of its status as an intermittant waterway to its confluence with Cassel Creek. Sampling periods included the months of April, May, June, July, October and November.

Macroinvertebrate collections were made at six locations along the stream approximately equidistant from each other. The organisms were assigned tolerance levels as designated by the Illinois Environmental Protection Agency.

Physical and chemical …


A Review Of The Limnology Of And Water Quality Standards For Lake Mead, Charles R. Goldman Oct 1976

A Review Of The Limnology Of And Water Quality Standards For Lake Mead, Charles R. Goldman

Publications (WR)

1. The waters of Las Vegas Bay, a heavily utilized recreational resource, receive discharges from a variety of municipal and industrial waste sources. The U.S. Environmental Protection Agency has determined, on the basis of numerous studies, that the present water quality violates state and federal standards and constitutes a public nuisance. Consultants have advised the Sewage and Wastewater Advisory Committee that rapid abatement of the alleged pollution conditions can be achieved by an advanced wastewater treatment (AWT) plant.

2. The major problems in Las Vegas Bay are an objectionable water color, excessive turbidity, noxious odors, and oxygen depletion in certain …


Report On Wastewater Disposal To Board Of County Commissioners, Clark County Nevada, Clair N. Sawyer Oct 1976

Report On Wastewater Disposal To Board Of County Commissioners, Clark County Nevada, Clair N. Sawyer

Publications (WR)

This report is concerned with the management of waste-waters and subsurface drainage from the City of Las Vegas and its environs and the BMI complex, all in Clark County, Nevada. The prime objective is to recommend a plan of action which will utilize the natural resources of the area in the least costly manner and still protect Lake Mead for recreational purposes and use as a public water supply, At this writing, conditions in the upper Las Vegas arm of Boulder Basin are quite unsatisfactory for some recreational purposes due to the extensive blooms of algae which develop. Experience at …


Distribution Of Stream Pollution In Lake Water, Richard W. Tew, Samuel S. Egdorf, James E. Deacon May 1976

Distribution Of Stream Pollution In Lake Water, Richard W. Tew, Samuel S. Egdorf, James E. Deacon

Publications (WR)

Wastewater effluent-laden waters from Las Vegas Wash (LVW) form a density current that may be detected in Boulder Basin of Lake Mead at considerable distances from the wash estuary. This led to the suspicion that water from the inflowing stream [40 mgd (1.5 X 105 cu m/day)] might not be rapidly diluted in the enormous volume of the lake [19 mil acre-ft (2.3 X 1010 cu m)], but might persist as a recognizable entity to the vicinity of the intake of a major water source for populous Clark County, Nev.

Because of the detection sensitivity implicit in the …


The Nature And Distribution Of Enteric Bacteria In Las Vegas Bay, Samuel S. Egdorf Apr 1976

The Nature And Distribution Of Enteric Bacteria In Las Vegas Bay, Samuel S. Egdorf

Publications (WR)

The distribution of water and of enteric bacteria of possible fecal origin into Las Vegas Bay from Las Vegas Wash was determined. Determination of distribution patterns was attained by applying the concept of the population component ratio of enteric bacteria. The development and application of new techniques and methods implicit in the application of the "component ratio" concept are discussed. The unreliability of thoroughly referenced techniques and methods generally accepted as standard are treated in detail. Physical factors affecting the distribution and deposition of enteric bacteria (including those of special public health importance) in Las Vegas Bay are also discussed.


Fisheries Report No 23 - The Management Of Nature Reserves In Western Australia, Andrew A. Burbidge, Trevor Evans Jan 1976

Fisheries Report No 23 - The Management Of Nature Reserves In Western Australia, Andrew A. Burbidge, Trevor Evans

Fisheries Research Reports

The number and area of Nature Reserves in Western Australia has grown rapidly in recent times. At 80 June 1975 there were 491 reserves with an area of 5 103 037 hectares. By 31 December 1975, with the inclusion of reserves for the Conservation of Flora in the definition of a Nature Reserve, there were 900 reserves totalling 5 317 965 ha. With the implementation of the Environmental Protection Authority's recommendations based on the Conservation Through Reserves Committee's Report on Systems 4, 8, 9, 10, 11 and 12 the Nature Reserve System will jump to 985 reserves with an area …


Report No 21 - A Resource Survey Of Woody Island, Archipelago Of The Recherche, J. Goodsell, A. Tingay, S. R. Tingay Jan 1976

Report No 21 - A Resource Survey Of Woody Island, Archipelago Of The Recherche, J. Goodsell, A. Tingay, S. R. Tingay

Fisheries Research Reports

A resource survey of Woody Island was undertaken by the three authors from 26 October, 1975 to 8 November, 1975.

The island has some unusual faunal and floral features not yet recorded for the Archipelago. These are discussed.

Some problems in relation to the island's management are identified.


An Evaluation Of The Fishery Resources Of The Thames River Watershed, Connecticut, Connecticut Department Of Environmental Protection May 1975

An Evaluation Of The Fishery Resources Of The Thames River Watershed, Connecticut, Connecticut Department Of Environmental Protection

Storrs Agricultural Experiment Station

No abstract provided.


Seasonal And Spatial Variation In Primary Productivity In Boulder Basin, Lake Mead, Clark County, Nevada, Isamu Aoki May 1975

Seasonal And Spatial Variation In Primary Productivity In Boulder Basin, Lake Mead, Clark County, Nevada, Isamu Aoki

Publications (WR)

The 14C light and dark bottle technique for measurement of primary production was utilized as a means of assessing the amount of inorganic carbon being converted Into organic form by the photosynthesis of phytoplankton populations In the Boulder Basin of Lake Mead.

Spatial and time series changes of productivity levels observed at eight sampling locations within Boulder Basin Indicate that the Influence of treated municipal arts' industrial effluent flowing into Les Vegas Bay is contributing high levels of available nutrients at Las Vegas Wash Inlet to cause productivity to approximate those levels associated with polluted waters.

Productivity levels at …


Fisheries Report No 16 - Notes On The Wildlife Of A Proposed Nature Reserve Around Lake Grace And Lake Chinokup, Western Australia, N. L. Mckenzie, W. K. Youngson Jan 1975

Fisheries Report No 16 - Notes On The Wildlife Of A Proposed Nature Reserve Around Lake Grace And Lake Chinokup, Western Australia, N. L. Mckenzie, W. K. Youngson

Fisheries Research Reports

During 1972 and 1973 plants and vertebrate animals were collected and recorded from a proposed 22 000 ha nature reserve centred on a chain of salt lakes in south-western Western Australia (33° 10' S - 33° 35' 8 and 118° 19' B - 118° 29' E).

The dominant plant species were collected, the structural formations desert bed and a vegetation map produced. Seven species of native terrestrial mammal and three species of bat were recorded.

Three of the terrestrial species are endemic to southwestern Western Australia, and two of these - Pseudomys occidentalis and Sminthopsis granulipes - are regarded as …


How To Make A Natural Resources Inventory, Community Natural Resources Inventory Project Jan 1975

How To Make A Natural Resources Inventory, Community Natural Resources Inventory Project

Maine Collection

A Handbook How to Make a Natural Resources Inventory for Your Community

Prepared by: James F. Connors, Sterling Dow III & Dean B. Bennett

Community Natural Resources Inventory Project (Title I, Higher Education Act), The University of Maine at Portland - Gorham (Project Sponsor) and The Maine Association of Conservation Commissions (Project Co-Sponsor), 1975.

"This handbook is published as a result of a grant from the U.S. Office of Education, Department of Health, Education and Welfare under the Higher Education Act, Title I. No official endorsement by the U.S. Office of Education should be inferred."

Contents: Preface / Introduction / …


Fisheries Report No 14 - Wilson Inlet - A Seasonally Closed Western Australian South Coast Estuary, R C.J. Lenanton Jun 1974

Fisheries Report No 14 - Wilson Inlet - A Seasonally Closed Western Australian South Coast Estuary, R C.J. Lenanton

Fisheries Research Reports

Considerable conflict has existed for many years between professional fishing, recreational usage and development in the west and south coast estuaries of Western Australia. One of the areas where intense conflict exists is Wilson Inlet.

The Government's task of advising the various interests concerned in these conflicts has been difficult, due to the lack of knowledge of estuarine fauna and environment in relation to usage and development.

The objective of this report is to present a preliminary description of the Wilson Inlet environment, to record the history of netting closures in the Inlet, and to discuss the history of the …


Finitely Generated Modules Over Bezout [email protected], Roger Wiegand, Sylvia Wiegand Apr 1974

Finitely Generated Modules Over Bezout [email protected], Roger Wiegand, Sylvia Wiegand

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Let R be a Bezout ring (a commutative ring in which all finitely generated ideals are principal), and let M be a finitely generated R -module. We will study questions of the following sort: (A) If every localization of M can be generated by n elements, can M itself be generated by n elements? (B) If M 0 R m = Rn for some m, n, is Af necessarily free? (C) If every localization of M has an element with zero annihilator, does M itself have such an element? We will answer these and related questions for various familiar classes …


The Use Of Color Infrared Aerial Photography In Determining Salt Marsh Vegetation And Delimiting Man-Made Structures Of Lynnhaven Bay, Virginia, Robert E. Holman Lll Apr 1974

The Use Of Color Infrared Aerial Photography In Determining Salt Marsh Vegetation And Delimiting Man-Made Structures Of Lynnhaven Bay, Virginia, Robert E. Holman Lll

Biological Sciences Theses & Dissertations

Color infrared aerial photography was found to be superior to color aerial photography in an ecological study of Lynnhaven Bay, Virginia. The research was divided into three phases: 1) determination of the feasibility of correlating color infrared aerial photography with wetland species composition and zonation patterns, 2) determination of the accuracy of the aerial interpretation and problems related to the aerial method used, and 3) comparison of developed with undeveloped areas along Lynnhaven Bay's shoreline.

Wetland species composition and zonation patterns of major cones were correlated with aerial infrared photography and resulted in a high degree of accuracy. Problems with …


Studies On The Causes Of Tree Distribution In A Forest Type In The Dismal Swamp National Wildlife Refuge, Thomas A. Janszen Apr 1974

Studies On The Causes Of Tree Distribution In A Forest Type In The Dismal Swamp National Wildlife Refuge, Thomas A. Janszen

Biological Sciences Theses & Dissertations

Vegetational composition and environmental parameters were analyzed in a forest type of the Dismal Swamp. A 0.5 ha forest stand was divided into 200 5 x 5 meter contiguous quadrats and the tree size classes were precisely mapped. Fifty soil samples were analyzed for texture, pH, and major nutrients. A topographic map was constructed with precision to 0.01 ft. Analysis of variance tests showed non-randomness to exist in soil texture and nutrient content while homogeneity tests showed non-randomness in distribution of some woody species. Factor analysis indicated no significant correlations between soil quality, topography, and woody species. Findings indicate that …


An Ecological Study Of The Craney Island Disposal Area In Hampton Roads, Virginia, David Wallace Laist Apr 1974

An Ecological Study Of The Craney Island Disposal Area In Hampton Roads, Virginia, David Wallace Laist

Biological Sciences Theses & Dissertations

A one year ecological study was conducted on the Craney Island Disposal Area in Hampton Roads, Virginia. This study attempted to identify the flora and fauna inhabiting the spoil deposits and trace the development of communities from the time of deposition through the initial stages of succession.

One hundred and ninety-two species were identified including 48 vascular plants, 66 insects, 48 birds, 18 species of algae, 4 crustaceans, and 8 vertebrates. The study area was divided into six zones based on substrate characteristics and species composition. The successional patterns and biotic interactions within each zone were discussed.


Seasonal Changes In Water Quality And Primary Productivity In Doe Valley Lake, Edmond J. Bacon, Stuart E. Neff Mar 1974

Seasonal Changes In Water Quality And Primary Productivity In Doe Valley Lake, Edmond J. Bacon, Stuart E. Neff

KWRRI Research Reports

Primary productivity and water quality were studied in Doe Valley Lake, a 147-hectare impoundment on Doe Run, a spring-fed stream in Meade County, Kentucky, from 13 June 1969 to 31 July 1972. Doe Valley Lake is monomictic during most winter seasons, but it is dimictic during more severe winters because of its morphometry and location on the borderline climatic region for dimictic lakes (37° N latitude). Oxygen depletion in the hypolimnion is severe, and anaerobic conditions usually prevail by late June. A hypolimnetic areal deficit of 0.038 mg/cm2/day was calculated. Supersaturation of oxygen in the epilimnion was common, …


Grain Moisture And The Weather : What Can The Records Tell Us?, M W. Perry, P. A. Fievez Jan 1974

Grain Moisture And The Weather : What Can The Records Tell Us?, M W. Perry, P. A. Fievez

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

The expansion of cereal production in areas along the south coast has exposed harvesting problems associated with high grain moisture.

A grain delivery standard of 12 per cent moisture means that, in the absence of grain drying facilities, harvesting times in the field are restricted to those hours when grain moisture falls below this figure.

Grain moisture, however, remains the major problem and for planning purposes, producers require an estimate of the harvesting time available in a given year. This will depend on all the climatic variables which affect grain moisture. These include rainfall and dew which deposit water directly …