Physical Sciences and Mathematics Commons^™

Trees Working In Western Australia, Dave Berry

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

There is an air of inevirability about farm forestry - no-one disputs that planting trees is a sure route to curbing agriculture's serious land degredation problem. Dave Berry talks with some of the key players developing the industry.

Focus Catchments : A New Approach To Salinity Research : National Dryland Salinity Program, Steve Porritt

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

Dry/and salinity is a major threat to the resource base of many rural industries around Australia. More than 1.8 million hectares of once productive land are affected by salinity, with a further 1.6 million hectares at risk in the next 15 to 25 years in Western Australia alone. Much of the past Commonwealth and State expenditure on salinity programs and activities has been poorly targeted and coordinated. In view of this, a national dry/and salinity program that supports specific State salinity management programs has been established jointly between the Commonwealth and State government agencies.

The Upper Kent River Catchment is …

Finfish Aquaculture In Western Australia, David Berry

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

David Berry surveys fish farming from Broome to Williams, on off shore reefs and in farm dams, for barramundi, silver perch and black bream, trout and tuna.

Salinity Action Plan, Department Of Agriculture And Food, Western Australia

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

In November, the Premier of Western Australia, Richard Court, released his governments strategy to tackle one of the State's most serious environmental problems - salinity. This article provides a summary of the action plan, full details are available in a two volum set 'Salinity - a situation statement for Western Australia' and 'Western australian salinity action plan'.

Copies of the reports are available from Publication Section, Agriculture Western Australia, 3 Baron-Hay Court, South Perth 6151. Phone (09) 368 3729

Something Fishy Is Going On - Aquaculture, David Berry

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

Aquaculture id Australia's fastest growing primary industry. Product from fish farms is currently valued at $399 million, forecast to exceed $5oo million by 2000.

Whilst the figure pales into insignificance alongside world production (about $45 billion) it does represent a huge window of opportunity for prospective investors and for Australian primary producers who are keen to diversify.

David Berry reports on the prospects for yabbie and marron farming in Western Australia.

Ribbons Of Blue, Martin Revell, Thelma Crook

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

Ribbons of Blue is a water quality awareness program that involves schools and community groups in monitering local water bodies.

The concept originated in the Environmental Policy Planning section of the Office of Premier and Cabinet, in 1989. Martin Revell and Thelma cook outline the scope of the program and highlight some major achievements.

No-Tillage Sowing Decreases Water Erosion On Loamy Soils And Increases Earthworm Activity, Kevin Bligh

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

No-tillage sowing places seed and fertiliser in the soil without loosening all of the topsoil. Soil is cultivated only in the sown rows, leaving the inter-row areas largely undisturbed.

No-tillage sowing reduces both wind and water erosion. Soil structure is generally improved, and pasture regeneration is increased because seed is not buried too deeply for re-establishment.

Two long-term trials were establis_hed on loamy soils to determine effects of tillage and cropping on runoff and soil loss.

Results Of Stubble Research In Western Australia, Michael Perry, Ron Jarvis, Mel Mason, David Tennant

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

Few farmers would question the desirability of retaining stubbles, both for control of erosion by wind and water, and to return organic matter to the soil. While the present debate is focused on the short term management of stubbles, longer term effects also need to be considered.

The Department of Agriculture has several long-running trials intended to measure long term effects.

Red Kangaroos Can Set Back Range Regeneration, Andrew Mclaughlin

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

After years of severe drought, stocking rates in Western Australia s arid rangelands have been kept low since the 1970s to allow native pastures to regenerate. As well, extensive re-seeding programs have started and sheep and cattle grazing on these areas has been restricted or eliminated. However, pasture regeneration in the rangelands can only succeed when grazing by all animals - sheep, cattle, kangaroos, goo.ts, camels, brumbies and donkeys - is controlled Many more red kangaroos roam throughout Western Australia's pastoral areas today than 20 years ago. The installation of windmills and troughs to water domestic livestock has allowed kangaroo …

How To Reduce Spending On Land Conservation, Tim Negus

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

Heavy spending on capital works for land conseroation is usually out of the question in the present financial climate, but the recession does not mean that landcare must be abandoned. There are many aspects of landcare that involve little or no extra cost. Soil conseroationist Tim Negus discusses them in this article.

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 …

Shallow Drains For Reducing Waterlogging And Salinity On Clay Flats, Don Mcfarlane, Tim Negus, Arjen Ryder

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

Flooding, waterlogging and salinity are problems which commonly occur together on the broad valleys of the wheatbelt. Drainage lines often become poorly defined once they reach the valleys and flood waters spread out, causing inundation and waterlogging. This excess water needs to be controlled because it contributes to salinity

Seepage Interceptor Drains For Reducing Waterlogging And Salinity, Don Mcfarlane, Jim Cox

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

Shallow interceptor drains can reduce waterlogging on sloping sites. Such drains will more than pay for themselves from the increased crop yield. Recent work has shown that these drains also decrease salinity so that they are cost-effective in the long as well as the short term.

Waterlogging : One Reason Why Our Crops And Pastures Are Not Achieving Maximum Yields, Department Of Agriculture And Food, Western Australia

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

Water, either its lack"or excess, is the main factor affecting the yield of crops and pastures in Western Australia.

Level Banks Used To Decrease Waterlogging Can Increase Salinity, Don Mcfarlane, Richard Engel, Arjen Ryder, Maurice Eales

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

Some farmers have used level W1SALTS banks to control surface zvaters above areas affected by ivaterlogging and salinity. Because the amount of waterlogging has been reduced, crop yields have increased downslope of some banks. However, the banks divert fresh surface water into deeper salty groundwater and, in the long term, worsen salinity. This article details an investigation of the effect of level WIS ALTS banks on saline groundwaters and discusses alternative methods of preventing the waterlogging of saline areas.

Coastal Plains : Land Use And The Environment, P R. George

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

Five years ago, this Journal of Agriculture reported on ways to overcome severe algal pollution of the Peel-Harvey estuarine system, 70 km south of Perth.

Several articles in this Journal of Agriculture discuss improved agricultural practices on the Swan Coastal Plain in particular, although the principals will apply to similar eutrophication of the Slbany harbours, Wilson Inlet and the Vassee-Wonnerup Estuary. They also emphasixe the fine balance between man's demand for potable water and land for rural, industrial and urban use.

Increasing Groundwater Salinity In The Northern Wheatbelt, R J. Mcgowan

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

Every farmer in western Australia's northern wheatbelt will know of a groundwater supply, be it bore, well or soak. that has become increasingly saline. The groundwater may have become more saline over a period of 15 years or more, or have been noticed only recently. Inevitably, the bore will lie within an area cleared for agriculture. This increase in groundwater salinity may be associated with soil salinisation. Although researchers have some understanding of the processes causing salinisation of groundwater in the wheatbelt and the extent of the problem, little is known about the rates of salinisation and groundwater rise. A …

Dam Site Selection In The North-Eastern Wheatbelt, J L. Frith

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

Western Australia's wheatbelt farm dams are dug three to eight metres deep and are generally sited in soils which either are inherently impermeable or can be made so during construction.

In the eastern and north-eastern wheatbelt, however, only a small proportion of the soils meets these criteria. Dam site selection in these areas therefore depends on a good knowledge ofwhich soils aresuitable and on our being able to locate them efficiently by using surface indications such as surface soil, natural vegetation or topographic features.

Northern Wheatbelt Water Supply Study, I A F Laing, R. M. Pridham

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

Department of Agriculture surveys have shown that many farms in Western australia's northern wheatbelt have inadequate water supplies. More than 80 per cent of all farms in that area depend soley on groundwater for watering livestock, a much higher percentage than for most other farming areas. Because groundwater salinities have increased in recent years, concern is held for the long-term future of this recource.

In contrast to more southern agricultural areas, farm dams in the northern wheatbelt are relatively uncommon. Only 30 per cent of the existing dams in the northern wheatbelt constitute effective water supplies. More than half of …

Sandplain Hardpan : A Different Dam Construction Material, A F. Mccrea

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

Before 1980, the Department of Agriculture did not believe that suitable farm dam materials could be found in light land soils. However Beacon earthmoving contractor, V> J> Pavlinovich, has demonstrated that where suitable cemented subsoils or 'hardpan' existed, a succcessful dam site could be found.

This material should not be confused with compaction or traffic hardpans ehich are dense layers of soil found near the surface. Traffic hardpans result from compaction of soil materials with the passage of vehicles and farm machinery. Rather, the hardpan referred to here is a natural subsoil layer that has been cemented by silica and …

Underground Water Supplies In The Wheatbelt, T T. Bestow

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

Underground water originates from rainfall. The size of the underground recource in any region is broadly related to the amount of rainfall. However, rainfall intensity and seasonal distribution are just as importent as the quality. A relatively small annual fall which consists of a series of heasvy showers or storms close together, may be a more effective source of recharge to underground water than a larger fall that is more evenly distributed over a longer period.

A large annual rainfall, however, is no guarantee that underground water supplies will be readily available. This is because soils and the underlying rocks …

A Central Midlands Catchment Study : The Prospects For Land Drainage, B J. Hillman, B. J

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

Flooding, waterlogging and salinity problems in Western Australia are complex. Usually broad areas of land are affected, thus it is hard for one farmer alone to combat the effects because the problem so often starts and finishes off his farm.

The Causes Of Saltland : A Case Study At Esperance, P R. George, S. C. Bull

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

A series of bores on the Esperance Downs Research Station has demonstrated that the groundwater levels change after clearing, and the relatiojnnship between groundwater levels and soil salinity has been emphasised. This pattern of hydrological change leading to soil salinity problems applies widely in the wheatbelt.

The Comprehensive Water Supply Scheme, K J. Kelsall

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

The Comprehensive Water Supply Scheme has been a great boon to the agricultural area, and it has received strong support from all political parties. The Scheme has been responsible for increased prosperity of country towns, the decentralisation of industry, and general improvements in the standard of living.

This is a look at the development of the Scheme.

Native Plants : Water Savers In The Garden, K S. Cole

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

The climate of Western Australia may be one of the best in the world for people but it is a difficult one for many of our imported, and common garden plants. as a consequence, some 70 per cent of our summer water usage is for gardens and lawns.

This is not the sort of statistic that we should accept easily or happily.

There is a solution to this problem: a new approach to home gardening is required.

The new garden is based on W. A.'s own colourful native plants, which are adapted to mild winters, hot dey summers and poor …

P.W.D. Supplementary Public Water Supply Schemes, J E. Davis

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

Shallow wells and soaks with very limited yields were the principal water sources for the early settlers.

Hundreds of such wells were constructed by the Public Works Department in remote areas.

In the early 1930s major development of water supplies from rock catchments was begun in the central wheatbelt.

After the war, larger and more effective earth moving equipment became available. The Public Works Department rehabilitated many old excavated dams as well as constructing new ones.

Roaded catchments were also developed during this post-war period. many farmers took advantage of Public Works Department technical advise and hired a P.W.D. grader …

Farm Dams In The Wheatbelt, I A F Laing

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

Of the estimated 76 000 farm dams in the wheatbelt, about 8 per cent either leak or are salt affected. The remaining 70 000 dams are capable of holding water for livestock use and can be regarded as sercicable dams.

A great many of the serviceable dams are unreliable water supplies due to the combined effects of lack of runoff from catchments, shallow depth of storage and small size of storage in relation to expected demand from livestock and evaporation loss.

Economics Of Farm Water Supplies, P P. Eckersley

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

The economics of farm water supplies can be studied in two ways. One is to compare the costs of alternative ways of supplying a specified quantity of water to a farm. Another is to calcu;ate how mucha farmer can afford or will pay for a water supply.

I propose to look at these questions from the point of vieew of an eastern wheatbelt farmer, assuming that he must pay the full costs of any water supply provided for his property.

Some Basics Of Marron Production, Department Of Agriculture, Western Australia

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

marron are native to the South-West of Western Australia, and are keenly sought by inland fisher-men. However, supplies do not equal the apparent demand.

One solution is to cultivate marron in farm dams, or more intensively as a commercial enterprise.

This article suggests a few guidelines for marron production.

Water Supplies On Wheatbelt Farms : A General Picture, I A F Laing

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

In good rainfall years, farm dams provide water fo more than 50 per cent of the total stock in the wheatbelt.

Other sources include ground water supplies and the piped Comprehensive Water Scheme.

The March 1970 census included questions on farm water supplies including how farmers coped in the 1969-70 drought.