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Department of Primary Industries and Regional Development, Western Australia

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Full-Text Articles in Physical Sciences and Mathematics

Fisheries Research Report No 91 - A Synopsis Of The Biology And The Exploitation Of The Australasian Pilchard, Sardinops Neopilchardus (Steindachner) Part Ii: History Of Stock Assessment And Exploitation, W. J. Fletcher Mar 1991

Fisheries Research Report No 91 - A Synopsis Of The Biology And The Exploitation Of The Australasian Pilchard, Sardinops Neopilchardus (Steindachner) Part Ii: History Of Stock Assessment And Exploitation, W. J. Fletcher

Fisheries Research Reports

This report summarises the studies which have provided information on the population characteristics and exploitation of the pilchard, Sardinops neopilchardus in Australia and New Zealand. This review was undertaken to determine whether existing data could be used to assess the status of Western Australian or other stocks or, alternatively, what additional information was required.

The mean size of pilchards caught varies among locations but, in general, fish are between 140 and 160 mm LCF, corresponding to ages 2 - 5 years. The length-weight relationship also varies between locations

Attempts to initiate pilchard fisheries have been hampered by the lack of …


The Mallee Road Catchment Project, Rachel Siewert, S Abbott, National Soil Conservation Program (Australia), R A. Nulsen Jan 1991

The Mallee Road Catchment Project, Rachel Siewert, S Abbott, National Soil Conservation Program (Australia), R A. Nulsen

Resource management technical reports

The Mallee Road Sump catchment is a 30,000 ha catchment located immediately south of a major drainage divide in the central southern agricultural region of Western Australia. The catchment has been largely developed for agriculture over the last 25 years and is now showing development of secondary land salinization. Agronomic trials have shown that it is possible to considerably increase plant production in the area and simultaneously reduce recharge to the groundwaters.


The Economic Impact Of Recreational Fishing In Western Australia., R. K. Linchner Jan 1991

The Economic Impact Of Recreational Fishing In Western Australia., R. K. Linchner

Fisheries Management Papers

The Minister for Fisheries commissioned Economic Research Associates to carry out a study of the economic impact of recreational fishing in Western Australia. Two surveys were conducted to determine how much recreational fishers spend during the year on goods and services in order to go fishing. One involved telephone interviews of 401 recreational fishers, who were selected from a stratified random sample of households in five major regions of the state. The other survey employed a self enumeration questionnaire sent to randomly selected licensed recreational fishers, as well as being made available on non-random self-selection basis through fishing clubs and …


Background Papers To Wawa's South-West Irrigation District Strategy Study, G J. Luke, I Af Laing, P R. George, G R. Olney, R L. Taylor, I F. Wilkinson, P T. Arkell Jan 1991

Background Papers To Wawa's South-West Irrigation District Strategy Study, G J. Luke, I Af Laing, P R. George, G R. Olney, R L. Taylor, I F. Wilkinson, P T. Arkell

Resource management technical reports

No abstract provided.


Pasture Condition Guides For The Murchison River Catchment, A Fox, T R. Eckersley Jan 1991

Pasture Condition Guides For The Murchison River Catchment, A Fox, T R. Eckersley

Soil conservation survey collection

Knowledge of the pasture resource and its capabilities is essential to sustainable use of the rangelands. Rangeland managers must be able to recognise firstly the different pasture types, and secondly, the differences between present condition classes for each type. Both factors affect the stock carrying capacity, and appropriate pastoral management of a pasture. This guide has been produced for use by pastoralists to assist them to recognise and assess the condition of the perennial pasture resource of their own properties. The guide describes the condition states found in 10 of the most widespread pastures of the Murchison River catchment (Fig. …


The Effect Of Nitrogen On Pastures And Subsequent Sheep Production., L. Cransberg Jan 1991

The Effect Of Nitrogen On Pastures And Subsequent Sheep Production., L. Cransberg

Experimental Summaries - Plant Research

Trial 89MT1

Location: Mt Barker Research Station

To measure the effect of autumn/winter application on:

1. Pasture growth rates and composition

2. Sheep production using pregnant/lacting ewes.

Trial 89KA6

Management systems for sheep.

Location: Kojonup

To measure the effects of set stocking and strip (rotation) grazing on:

1. Pasture production, composition and quality.

2. Sheep production (liveweight, condition score, wool growth rate, fibre diameter strength and vegetable matter contamination).


Performance Of Annual Legumes And Their Mixes Under Different Crop:Pasture Rotation., P. Evans Jan 1991

Performance Of Annual Legumes And Their Mixes Under Different Crop:Pasture Rotation., P. Evans

Experimental Summaries - Plant Research

Trial 86KA64, 86KA65 and 86KA66

Performance of annual legumes and their mixtures under different crop:pasture rotations.

Seed reserves, especially in the 1:1 rotation treatment, are on average below 100 kg/ha and in many cases below 50 kg/ha for all three soil types. Because of this the 1991 season will be used to fertilize, control weeds, and apply a grazing management system to favour legume production and seed set. No crop will be sown in 1991.

Sub clover flowering, sequential sowings.

Location: Katanning

To provide seven different temperature and photoperiod regimes, eight cultivars of sub clover ranging in maturity from Nungarin …


Survey Of The Damage Caused To Trees By Goats, Steve Gherardi, Dick Mills, Tim Johnson Jan 1991

Survey Of The Damage Caused To Trees By Goats, Steve Gherardi, Dick Mills, Tim Johnson

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

The damage that goats can cause to trees is one of the major problems associated with their farming in the agricultural areas of Australia. It is also considered one of the main hindrances to the development of the goat industry. The Department of Agriculture s Goat Industry Development Unit surveyed mohair and cashmere producers to determine the prevalence of tree damage and its extent and severity; why producers believed goats damaged trees; and how producers minimised or prevented this damage.


Variable Quality Of Saltbush Seed Influences Establishment, Stephen Vlahos, Donald Nicholas, Clive Malcolm Jan 1991

Variable Quality Of Saltbush Seed Influences Establishment, Stephen Vlahos, Donald Nicholas, Clive Malcolm

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

Farmers are using niche seeders to direct-seed saltbushes (Atriplex spp.) cheaply on large areas of salt affected land. While many factors influence successful establishment of these shrubs, fanners can control the quality of the seed they use. Too often, the lack of knowledge of saltbush seed quality has resulted in extremely poor establishment. The importance of seed quality is well recognized in the establishment of grain crops and pastures, but it is often overlooked when farmers buy or select seed of saltbush. If farmers know the quality of the seed they buy, they can make appropriate adjustments to the sowing …


Seed Phosphorus In Wheat And Lupins, Blakely Paynter, K. Adcock, R. W. Bell, Tim Pope Jan 1991

Seed Phosphorus In Wheat And Lupins, Blakely Paynter, K. Adcock, R. W. Bell, Tim Pope

Experimental Summaries - Plant Research

Trial 90NO119

Seed P in wheat.

Location: Greenhills.

Design: 2 applied P x 3 seed P x 4 replicates, sowing wheat (cv. Aroona) seed from 89N33 at 70 kg/ha on May 15, 1990.

Trial 90NO120

Seed P in wheat.

Location: York

Design: 2 applied from P x 3 seed P x 4 replicates, 89N33 at 70 kg/ha on May 25, 1990.

Trial 90NO117

Seed P in lupins

Location: Greenhills.

Design: 2 applied P x 3 seed P x 4 replicates, sowing lupins (cv. Gungurru) from 85BA35 at 100 kg/ha on May 15, 1990.

Trial 90NO118

Seed P in lupins.

Location: …


Adjusting Farm Strategy To Allow For Seasonal Conditions, Andrew Bathgate, Stephen Robinson, Ross Kingwell Jan 1991

Adjusting Farm Strategy To Allow For Seasonal Conditions, Andrew Bathgate, Stephen Robinson, Ross Kingwell

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

Changes in the price of wheat did not alter the selection of best rotations on various soils, or the area of crop, in an economic study done by the Department of Agriculture. When determining what area to crop, it is much more important to consider the type of start to the season, the amount of summer rainfall and whether light land can be sown early. If there is a good start to the season, the size of the increase in the area of crop depends on the capacity of seeding gear and the mix of soil classes on the farm.


Remnant Vegetation On Farms Is A Valuable Resource, Richard Hobbs, Ken Wallace Jan 1991

Remnant Vegetation On Farms Is A Valuable Resource, Richard Hobbs, Ken Wallace

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

Retention of native vegetation on farms is important both from an ecological and an economic point of view. Productivity in the paddocks ultimately will depend on the retention and replacement of trees and shrubs in the landscape. Remnants of native vegetation can play their part by helping to ensure the long-term viability of the agricultural system, as well as greatly enhancing the quality of life for those living on the land.


Reclaiming Sandplain Seeps Planting Trees, Richard George Jan 1991

Reclaiming Sandplain Seeps Planting Trees, Richard George

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

Sandplain seeps affect large areas of agricultural land in Western Australia's eastern and northern wheatbelt and in the Great Southern. These seeps are estimated to account for about 10 per cent of dryland salinity in the agricultural area. Research and field observations show that seeps may be cheaply and quickly reclaimed using various types of drains or small blocks of trees (George 1990). This article discusses results of reclamation methods associated with tree planting on sandplain seeps in the eastern wheatbelt.


Planting Trees To Control Salinity, Nick Schofield, Phil Scott Jan 1991

Planting Trees To Control Salinity, Nick Schofield, Phil Scott

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

Dense tree plantings covering at least 30 per cent of cleared land can lower groundwater levels by two metres or more in 10 years from the time of planting. This sizeable drop can be expected at sites receiving 700 to 800 mm of rain a year. Research by the Water Authority of Western Australia shows the most promising strategy when using trees is to put dense plantings on the discharge zone and on lower to midslopes. This strategy is successful where groundwaters contain less than 30,000 milligrams per litre total soluble salts (TSS).

This article discusses research in the 450 …


Windbreaks Prove Their Worth, Tim Negus Jan 1991

Windbreaks Prove Their Worth, Tim Negus

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

Strong winds in the south-west of Western Australia in April 1991 carted tonnes of top soil from stubbles, over-grazed pastures, and recently prepared cropping land. However, where there were windbreaks, downwind protection into the paddock was up to 10 to 20 times the height of the windbreaks. On May 1, 1991, the author inspected farm land for damage from Narrogin to the Dongolocking area, to Harrismith, up the rabbit-proof fence to West Corrigin and back to Narrogin via Kweda. He found the extent of soil erosion varied, and that some tree species planted in windbreaks gave better protection than others


Trees And Livestock : A Productive Co-Existence, Richard Moore Jan 1991

Trees And Livestock : A Productive Co-Existence, Richard Moore

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

Trees, as part of farming can help to combat land degradation problems and produce a good economic return from timber at the same time. For example, there is now clear evidence that planting trees can help combat salinity by lowering water-table levels. Trees can also substantially improve overall farm productivity by providing shelter for pastures and livestock. The challenge is to find practical and economical methods of integrating trees and farming. A combination of widely-spaced trees and livestock is one promising method. This article describes the benefits of this type of agroforestry to farmers, suitable locations and how to practice …


Drainage Of Sandplain Seeps For Salinity Control And Stock Water Supplies, Richard George, Peter Frantom Jan 1991

Drainage Of Sandplain Seeps For Salinity Control And Stock Water Supplies, Richard George, Peter Frantom

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

Sandplain seeps are derived from a shallow groundwater system which flows from the deep sandplain soils upslope. Seeps result in small areas of salinity and waterlogging, which can be the focus of soil erosion. Sandplain seeps may represent as much as 10 per cent of Western Australia's salt problem in the drier agricultural area. Several drainage experiments conducted between 1986 and 1989 determined the best methods of reclaiming sandplain seeps.

This article discusses the results of these drainage experiments. It comments on the most suitable method for reclaiming sandplain seeps and developing them for stock water supplies.


Whole-Farm Planning : Success At Wilgi Creek, Kevin Shanhun Jan 1991

Whole-Farm Planning : Success At Wilgi Creek, Kevin Shanhun

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

Ian and Bev Lynch own Wilgi Creek, a 376 ha mixed farming property at West Mount Barker in the 700 mm rainfall zone. In 1983, they started a whole-farm plan to overcome the problems of declining production caused by waterlogging (their biggest problem), salinity and deterioration of the remnant native vegetation. Today, their property is an example of a successful, wholefarm land conservation plan based on agroforestry, timber production, water harvesting and improved pastures.


Unique Co-Operative Landcare Venture In The Avon Catchment, Darrel Brewin, John Collett Jan 1991

Unique Co-Operative Landcare Venture In The Avon Catchment, Darrel Brewin, John Collett

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

The Avon catchment is bustling with landcare activity generated by a unique co-operative venture between farmers, the Department of Agriculture, the National Soil Conservation Program and Alcoa of Australia Ltd. The Avon Catchment Landcare Program was initiated by the Department of Agriculture and Alcoa, in support of the national Decade ofLandcare. The program provides financial, human and technical resources to undertake catchment and farm planning and demonstrations of rehabilitation techniques that tackle soil and water degradation problems. We know that without specially planned landcare programs and substantial changes in land management, land degradation will continue and further losses of agricultural …


Using Trees To Reclaim Land Lost To Saline Seeps, Department Of Agriculture And Food, Western Australia, Arthur Wright Jan 1991

Using Trees To Reclaim Land Lost To Saline Seeps, Department Of Agriculture And Food, Western Australia, Arthur Wright

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

The National Soil Conservation Program (NSCP) has tapped the vigorous community support for landcare initiatives through its demonstration sites for reclaiming sandplain seeps in the Western Australian wheatbelt. The demonstrations, which use tree plantations to reclaim seeps, began in 1989. The sites are being keenly monitored by participating farmers and members of land conservation districts (LCDs).


Land Capability Study For Horticulture In The Swan Valley, J M. Campbell-Clause, Geoff Allan Moore Jan 1991

Land Capability Study For Horticulture In The Swan Valley, J M. Campbell-Clause, Geoff Allan Moore

Land resources series

The Swan Valley is an important agricultural, recreational, tourist and heritage area in which there are a number of competing land uses because of its location close to Perth. The traditional agricultural use, mainly centred around the viticulture industry, has to compete with tourist development, urban encroachment, hobby farms and clay extraction. The major objective of this report was to identify any areas of prime horticultural land which should be retained for that purpose. A land capability study was done using the existing soil series map of the Swan Valley (Pym 1955), which covers most of the Swan Valley Policy …


Development Of Procedures To Determine The Fertilizer Requirements Of Annual Pasture Legumes Grown In Cereal Cropping Systems., Blakely H. Paynter Jan 1991

Development Of Procedures To Determine The Fertilizer Requirements Of Annual Pasture Legumes Grown In Cereal Cropping Systems., Blakely H. Paynter

Experimental Summaries - Plant Research

Trials 88ME67, 88SC17, 90ME1 and 90ME2

Location: Merredin

To determine the phosphate (P) fertilizer requirements of burr medic on marginally acidic, medium textured soils and yellow serradella on acidic, light textured soils.

Trials 89ME52, 89ME55 and 86ME61

Location: Merredin

Determine the response of yellow serradella and burr medic to residual phosphate and freshly applied phosphate.

Trials 89ME50, 89ME54, 88ME67, 88SC17, 89ME60

Location: Merredin.

To measure the influence of different levels of pasture productivity (generated by different levels of P supply) and the different pasture legumes on subsequent wheat crops.


Regenerating The Rangelands, Adrian Williams, Ron Shepherd Jan 1991

Regenerating The Rangelands, Adrian Williams, Ron Shepherd

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

Parts of Western Australia's rangelands have been degraded by inappropriately high stocking rates, often associated with large numbers of native or feral animals, poor seasonal plant growth, or the ravages of cyclones, floods or fire. Today, most pastoralists are keen to rehabilitate the degradation of the past, as indicated by the proliferation of Land Conservation Districts (LCDs) throughout the pastoral zones.

There is no 'quick fix' to regenerating the rangelands. It may take many years to achieve the desired result.


Pasture And Fodder Shrub Species For Deep Sandy Soils., Tim Wiley Jan 1991

Pasture And Fodder Shrub Species For Deep Sandy Soils., Tim Wiley

Experimental Summaries - Plant Research

Trial 90MO64

The evaluation of alternative pasture species on deep sandy soils.

Location: Moora.

Soil type: Deep siliceous sand, moisture at depth pH 5.9 - 6.1 in CaC12.

Trial 90MO65

The evaluation of alternative pasture species on deep sandy soils.

Location: West Gillingarra

Soil type: Deep siliceous sand, moisture at depth pH 5.9 - 6.0 in CaC12

Trial 90MO66

The evaluation of alternative pasture species on deep sandy soils.

Location: West Koojan

Soil type: Deep siliceous sand pH 5.8 - 5.9 in CaC12

Trial 89BA40

Tagasaste establishment trial

Location: Badgingarra Research Station.

Soil type: poor quality …


The Greening Of Australia, Martine Scheltema Jan 1991

The Greening Of Australia, Martine Scheltema

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

Many urban Australians have little understanding of the problems of land degradation because it's an extremely slow process that doesn 't directly influence their day-to-day lives. Understandably, they would have trouble relating to sub-soil compaction, waterlogging, increased soil acidity and salinity. They also have trouble comprehending why fencing according to soil type is an important management tool for farmers, or what role contour banks, drainage systems, the addition of gypsum and planting trees have in reversing land degradation. But given that tree loss "has been at the core of almost every aspect of land degradation in Australia ", and that …


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.


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


Wildlife Corridors In The Wheatbelt, Richard Hobbs, Denis Saunders Jan 1991

Wildlife Corridors In The Wheatbelt, Richard Hobbs, Denis Saunders

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

Native vegetation in the Western Australian wheatbelt now persists mostly in small areas that remained uncleared for various reasons. (See 'Remnant vegetation on farms is a valuable resource' on page 43.) On their own, most of these remnant areas are difficult to manage, and too small to retain viable populations of many of the birds and other animals found in the wheatbelt. These patches of vegetation can be linked by wildlife corridors, which may increase the ability of the wildlife to move about and persist in the area


Revegetating Salt-Affected Land With Shrubs, Ed Barrett-Lennard, Fionnuala Frost, Steve Vlahos, Norm Richards Jan 1991

Revegetating Salt-Affected Land With Shrubs, Ed Barrett-Lennard, Fionnuala Frost, Steve Vlahos, Norm Richards

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

The establishment of salt-tolerant shrubs such as saltbush and bluebush on salt-affected land reduces the risk of soil erosion, and can also fit into farm programmes as a profitable enterprise. Salt-tolerant shrubs can be used as forage for sheep in summer and autumn, when the availability of annual pastures is low or annual pastures are just beginning to emerge. This article describes three methods for establishing shrubs on salt-affected land and what affects shrub establishment.


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.