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Crop Monitoring Handbook 1979, Department Of Agriculture, Western Australia May 1979

Crop Monitoring Handbook 1979, Department Of Agriculture, Western Australia

Grain and other field crops published reports

Prepared by the Plant Research Division of the Department of Agriculture for farmers who wish to keep detailed records of crop growth with the aim of achieving higher yields in the future.


Interrelationships Between Benthic Macroinvertebrates And Habitat In A Mountain Stream, John M. Payne May 1979

Interrelationships Between Benthic Macroinvertebrates And Habitat In A Mountain Stream, John M. Payne

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study to determine habitat differences of benthic macroinvertebrates was conducted on the upper Strawberry River, Utah. The investigation was part of a large scale project to determine minimum stream flow requirements for trout. The effects of time, habitat, depth and velocity on the distribution of benthic fauna were evaluated.

Samples of benthic invertebrates (146 total) were collected every 2 months at 8 stations on the river from November, 1975 through August, 1976. Representatives of 59 taxa were collected. Eight taxa comprised 90 percent of the mean annual community standing crop in numbers. Biomass was not dominated by any group …


Reproductive Modes Of The Least Chub (Iotichthys Phlegethontis - Cope), Marianne Crawford May 1979

Reproductive Modes Of The Least Chub (Iotichthys Phlegethontis - Cope), Marianne Crawford

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The reproductive biology of the least chub Iotichthys phlegethontis (Cope) was studied from June 1976 to March 1978. Fish from both field and laboratory populations of the Leland Harris Spring Complex, Juab Co., Utah were utilized in the study. Reproduction in 1977 occurred from April to July in the field population and from April through August in the laboratory population.

Reproduction was determined from gross examination and weight measurements of testes and ovaries, breeding coloration in males and diameter measurements of ova.

Males and females matured at about the same size, 28 to 30 mm TL. The number of mature …


Biology, Reproductive Potential And The Impact Of Fishing Pressure On The Bluegill Fishery Of Pelican Lake, Uintah County, Utah, Bob D. Burdick May 1979

Biology, Reproductive Potential And The Impact Of Fishing Pressure On The Bluegill Fishery Of Pelican Lake, Uintah County, Utah, Bob D. Burdick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Certain aspects of the biology of two species of fish, bluegill (Lepomis macrochirus) and largemouth bass (Micropterus salmoides), and the assessment of fishing pressure upon the sport fishery of Pelican Lake, Uintah County, Utah, a 680 ha warmwater lake, were studied between April 1, 1976 and June 30, 1978. The growth rate of bluegills (sexes combined) was fairly rapid; the mean back-calculated total lengths from ages one through nine were 55, 112, 166, 194, 211, 229, 245, 256 and 259 mm. The growth of largemouth bass was 104, 194, 271, 316, 350, 405 and 416 mm …


Development And Validation Test Of A Mule Deer Habitat Rule, Glenn Gephart May 1979

Development And Validation Test Of A Mule Deer Habitat Rule, Glenn Gephart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mathematical description of Rocky Mountain mule deer (Odocoileus hemionus hemionus) habitat was developed and subjected to validation testing using correlation and multiple regression statistical techniques. Data were collected on a central Utah study area, which was divided into mountain and desert regions.

Data on deer utilization and several habitat components from 86 study plots visited in 1976 were used to develop a habitat rule. Data from 46 study plots visited in 1977 were used to test the accuracy of the rule. Deer utilization was determined from pellet group counts on 20 0.001 ha pellet plots at each …


Information Transfer And Regulation In A Model Ecosystem With Environmental Stochasticity, M. Mckee May 1979

Information Transfer And Regulation In A Model Ecosystem With Environmental Stochasticity, M. Mckee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The concept of regulation in ecosystems has been given considerable attention in the ecological literature, but no formal treatment has been offered. This study proposes a rigorous definition of regulation which is derived from the mathematics of information and communication theory. A theoretical, mathematical equivalent of the definition is also offered which implies serious limitations as to the value of most traditional laboratory population studies and deterministic population models in understanding regulation in ecosystems. The empirical validity of this theoretical equivalence is tested through use of a competition model of two diatoms. Other observations concerning the relationship between environmental variability …


Some Effects Of A Grazer, Hyalella Azteca On Ecosystem Level Properties In Aquatic Microcosms, Martin D. Werner May 1979

Some Effects Of A Grazer, Hyalella Azteca On Ecosystem Level Properties In Aquatic Microcosms, Martin D. Werner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study to determine some ecosystem level effects of an aquatic invertebrate grazer, Hyalella azteca, was performed in aquatic ix microcosms. Impact of the grazer was assessed in three general areas: 1) inorganic nutrient levels of the microcosm water column, 2) productivity and respiration of the biotic community, and 3) plant community composition in the microcosms.

The grazing amphipod caused inorganic phosphorus and nitrogen (except ammonia) levels to be elevated in the microcosms. The increase was due, at least partially, to excretion of nutrients into the water by the amphipod. The presence of H. azteca did not significantly …


Two Basic Methodological Choices In Wildland Vegetation Inventories: Their Consequences And Implications, Donald Alan Shute May 1979

Two Basic Methodological Choices In Wildland Vegetation Inventories: Their Consequences And Implications, Donald Alan Shute

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In designing inventories of wildland vegetation, two of the many basic methodological choices are: 1) whether data are collected, reduced, and stored in discrete classes or as continuous variables, and 2) whether data are gathered as general purpose variables to bear upon many questions, or as specific purpose variables optimized for only one type of prediction. The effects of these two choices on accuracy of vegetation inventories to predict plant community production were examined by comparing regression models built upon differing sets of independent variables "inventoried" from a common data base. Contrary to expectations, discrete variables of classified community types …


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.


The Prairie Naturalist Vol. 11, No. 1. March, 1979 Mar 1979

The Prairie Naturalist Vol. 11, No. 1. March, 1979

The Prairie Naturalist

ORIN ALVA STEVENS, A PRAIRIE NATURALIST ▪ G. Monson

FIRST RECORD OF LONG-TAILED JAEGER FOR NORTH DAKOTA ▪ T. Gatz and D. Treasure

NEW RECORDS OF THE DWARF SHREW (SOREX NANUS) IN SOUTH DAKOTA ▪ R. J. Cinq-Mars, R. S. Hoffmann and J. K. Jones, Jr.

THE ETHYLENE FROM BURNING LIGNITE AS A PROBABLE CAUSE OF COLUMNARITY IN NORTH DAKOTA JUNIPERS ▪ J. M. Murphy and D. J. Holden

CAMOUFLAGED COYOTE DEN ENTRANCES ▪ D. P. Althoff

CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA - 1978 ▪ R.N. Randall

NOTES

An Upland Nest of the Virginia Rail in North …


Planting Trees-Why Rather Than How, Angelo Cohn Jan 1979

Planting Trees-Why Rather Than How, Angelo Cohn

Journal of the Minnesota Academy of Science

Three evergreen plantings over 25 years in a private woodland are described and evaluated in terms of reforestation, economics and personal satisfaction. Credit is given to government foresters and support from the Minnesota Department of Natural Resources (DN\R) and the federal Forest Incentives Program (FIP). Changes in site preparation methods, selection of species and planting procedures are discussed as outcomes of research and field experience. Cost-benefits are assigned principally to human values reflected in family learning and enhanced appreciation of the ecosystem of rural Minnesota.


Gas Exchange, Carbon Balance And Productivity Of Great Basin Shrub-Dominated Communities, M. M. Caldwell, L. B. Camp, R. S. Holthausen, H. Neuber Jan 1979

Gas Exchange, Carbon Balance And Productivity Of Great Basin Shrub-Dominated Communities, M. M. Caldwell, L. B. Camp, R. S. Holthausen, H. Neuber

Memorandum

No abstract provided.


Pine Valley Validation Site Report, C. D. Jorgensen Jan 1979

Pine Valley Validation Site Report, C. D. Jorgensen

Memorandum

No abstract provided.


Effects Of Grazing On Desert Vegetation, B. E. Norton, D. J. Bermant Jan 1979

Effects Of Grazing On Desert Vegetation, B. E. Norton, D. J. Bermant

Memorandum

No abstract provided.


The Impact Of Seed Consumers In A Desert Ecosystem: An Integrated Approach, W. G. Whitford Jan 1979

The Impact Of Seed Consumers In A Desert Ecosystem: An Integrated Approach, W. G. Whitford

Memorandum

No abstract provided.


Comparison Of Biological Processes In Western Deserts, J. Skujins Jan 1979

Comparison Of Biological Processes In Western Deserts, J. Skujins

Memorandum

No abstract provided.


Plant Growth And Water Transfer Processes Under Desert Conditions, L. Gay, T. Sammis, D. D. Evans Jan 1979

Plant Growth And Water Transfer Processes Under Desert Conditions, L. Gay, T. Sammis, D. D. Evans

Memorandum

No abstract provided.


Cryptobiosis And Its Effect On Metabolism And Production Estimates Of Desert Nematodes, D. W. Freckman Jan 1979

Cryptobiosis And Its Effect On Metabolism And Production Estimates Of Desert Nematodes, D. W. Freckman

Memorandum

No abstract provided.


Nitrogen Transformation In Rock Valley And Adjacent Areas Of The Mohave Desert, R. B. Hunter, A. Wallace, E. M. Romney Jan 1979

Nitrogen Transformation In Rock Valley And Adjacent Areas Of The Mohave Desert, R. B. Hunter, A. Wallace, E. M. Romney

Memorandum

No abstract provided.


Deep Creek Validation Study Report, G. W. Minshall, C. Y. Manuel, R. W. Dunn, R. K. Pace, M. R. Mcsorley, D. A. Andrews Jan 1979

Deep Creek Validation Study Report, G. W. Minshall, C. Y. Manuel, R. W. Dunn, R. K. Pace, M. R. Mcsorley, D. A. Andrews

Memorandum

No abstract provided.


Interactions Of Winter Sheep Grazing And Small Mammal Populations, C. D. Jorgensen Jan 1979

Interactions Of Winter Sheep Grazing And Small Mammal Populations, C. D. Jorgensen

Memorandum

No abstract provided.


Clustar And Clustid: Programs For Hierarchical Cluster Analysis, K. A. Marshall, H. C. Romesburg Jan 1979

Clustar And Clustid: Programs For Hierarchical Cluster Analysis, K. A. Marshall, H. C. Romesburg

Memorandum

No abstract provided.


Fisheries Report No. 37 - An Inventory Of The Marine Resources Of The Bunbury Marine Area And Geographe Bay, Michael H. Walker Jan 1979

Fisheries Report No. 37 - An Inventory Of The Marine Resources Of The Bunbury Marine Area And Geographe Bay, Michael H. Walker

Fisheries Research Reports

The marine resources of the Geographe Bay/Bunbury marine area were investigated using a variety of fishing gear i.e. set lines, set nets, trawls, ring nets, beach seines, hand lines, trolling lines, traps and light attraction at night. All the ftsh species caught were documented as to breeding state and food habits.

Commercial species encountered as adults during fishing operations were: bronze whaler, whiskery and gummy sharks, Westralian jewfish, Australian herring, skippy, flathead, oriental bonito, blue and sandy sprat, pilchard, mulloway, whiting, yellowtail scad, flounder, and leatherjacket and as juveniles were: skippy, yellowtail scad, tailor, southern sea garfish, pilchard, blue and …


Fisheries Report No 33 - The Western Rock Lobster Fishery 1975 - 1976, G. R. Morgan, E H. Barker Jan 1979

Fisheries Report No 33 - The Western Rock Lobster Fishery 1975 - 1976, G. R. Morgan, E H. Barker

Fisheries Research Reports

iTshe fishery for the western rock lobster Panultrus ecygnus one of the most important single fisheries in Australia and an important export earner for the State. The fishery is governed by a complex set of regulations which have been reviewed by Bowen (1971) and which are designed to limit the total effort to acceptable levels and to enforce a legal minimum size. It is thus important to constantly monitor the state of the fishery both to ensure that the effort is remaining within the accepted limits and that the regulations are adequately performing their function of maintaining reasonably stable catches. …


Fisheries Report No 34 - The Status Of The Salt-Water Crocodile In The Glenelg, Prince Regent And Ord River Systems, Kimberley, Western Australia, A. A. Burbidge, H. Messel Jan 1979

Fisheries Report No 34 - The Status Of The Salt-Water Crocodile In The Glenelg, Prince Regent And Ord River Systems, Kimberley, Western Australia, A. A. Burbidge, H. Messel

Fisheries Research Reports

Counts were made of Salt-water Crocodiles (Crocodylus porosus) in the estuarine portions of the Glenelg, Prince Regent and Ord River systems of the Kimberley Division, Western Australia. During the survey 581 crocodiles were seen, including 143 hatchlings. The number of non-hatchling crocodiles in present the Glenelg system is estimated to be 200 to 259, in the Prince Regent 190 to 246 and in the Ord 235 to 306 (95% confidence limits).

The number of non-hatchling crocodiles present in the six Kimberley river systems now counted is estimated to be between 957 and 1243 (95% confidence limits) and we believe that …


Fisheries Report No 38 - The Shark Bay Prawn Fishery (1970 - 1976), J. W. Penn, R. W. Stalker Jan 1979

Fisheries Report No 38 - The Shark Bay Prawn Fishery (1970 - 1976), J. W. Penn, R. W. Stalker

Fisheries Research Reports

The existence of prawn stocks in Shark Bay, Western Australia, has been known since 1904 when the sailing ketch "Rip" on charter to the Western Australian Government, trawled large quantities of prawns from the area between Bernier Island and the mainland, Gale (1905). Although the Fisheries research vessel "Lancelin" trawled potentially commercial quantities of prawns from Shark Bay in the early 1950's, it was not until 1962 that a regular fishery was begun.

Today the prawn stocks of Shark Bay support Western Australia's largest and most consistent prawn fishery, having an annual production currently exceeding 2 000 tonnes. The catch …


Plant Productivity And Nutrient Interrelationships Of Perennials In The Mohave Desert, A. Wallace, A. T. Vollmer, R. T. Mueller, J. W. Cha Jan 1979

Plant Productivity And Nutrient Interrelationships Of Perennials In The Mohave Desert, A. Wallace, A. T. Vollmer, R. T. Mueller, J. W. Cha

Memorandum

No abstract provided.


Gas Exchange Of Sonoran Desert Plants, S. R. Szarek, R. M. Woodhouse Jan 1979

Gas Exchange Of Sonoran Desert Plants, S. R. Szarek, R. M. Woodhouse

Memorandum

No abstract provided.


Nitrogen Cycling In Great Basin Desert Soils, J. Skujins, B. Klubek Jan 1979

Nitrogen Cycling In Great Basin Desert Soils, J. Skujins, B. Klubek

Memorandum

No abstract provided.


Biology Of Nematodes In Desert Ecosystems, R. Mankau Jan 1979

Biology Of Nematodes In Desert Ecosystems, R. Mankau

Memorandum

No abstract provided.