Engineering Commons^™

Sheep Updates 2007 - Part 4, Dean Thomas, Dominique Blache, Dean Revell, Hayley Norman, Phil Vercoe, Zoey Durmic, Serina Digby, Di Mayberry, Megan Chadwick, Martin Sillence, David Masters, R. Silberstein, F. Byrne, P. G. H. Nichols, J. Young, L. Aitkins, M. G. Wilmot, A. J. Rintoul, T. Lambert, D. R. Mcclements, P. Raper, P. Ward, C. Walton, T. York, David Pethick, David Hopkins, Malcolm Mcphee, D. B. Savage, J. V. Nolan, I. R. Godwin, A. Aoetpah, T. Nguyen, N. Baillie, C. Lawler, Ken Geenty, John Smith, Darryl Smith, Tim Dyall, Grant Uphill, John Young, Michael Paton, John Dorrian

Sheep Updates

This session covers eight papers from different authors:

GRAZING

1. The impact of high dietary salt and its implications for the management of livestock grazing saline land, Dean Thomas, Dominique Blache, Dean Revell, Hayley Norman, Phil Vercoe, Zoey Durmic, Serina Digby, Di Mayberry, Megan Chadwick, Martin Sillence and David Masters, CRC for Plant-based Management of Dryland Salinity, Faculty of Natural & Agricultural Sciences, The University of Western Australia, WA.

2. Sustainable Grazing on Saline Lands - outcomes from the WA1 research project, H.C. Norman^1,2, D.G. Masters^1,2, R. Silberstein^1,2, F. Byrne^2,3, P.G.H. Nichols …

Deep Drains To Manage Groundwater, Neil Cox, Sylvia Tetlow, Neil Coles

Bulletins 4000 -

A channel that is 1.0 m to 3.0 m in depth is considered to be a deep drain. The drain is excavated to a depth that is sufficient to intercept the watertable in order to capture and convey that groundwater from flat, poorly drained land.

The drain can either be ‘open’ to allow the inflow of surface water or ‘leeved’ to exclude surface water. An open deep drain has its spoil banks placed on one side or on alternate sides of the channel (Figure 1) while a leveed deep drain has continuous spoil banks placed on both sides of the …

An Assessment Of The Efficacy Of Deep Drains Constructed In The Wheatbelt Of Western Australia Part 1 A Discussion On Drainage Implmentation In The Wheatbelt : A Case Study Review, Summary, Conclusions And Recommendations, N A. Coles, Richard J. George Dr, A D. Bathgate

Bulletins 4000 -

Australia has undertaken a strategic review of current and historical deep drainage projects. A 'rapid appraisal' methodology was utilised, based principally on existing hydrological investigations and interpretation and anecdotal evidence provided by landholders to clarify the role of drainage in managing water in dry land rural landscapes.

The objectives of this discussion paper are to:

1. Review the current status of groundwater drainage practice

2. Provide an assessment of deep drains in the landscape and

3. Propose recommendations on the development of drainage policy to enable the application of best management practice in groundwater drainage.

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.

Seepage Interceptor Drains And Topsoil Salinity, T R. Negus

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

The Department of Agriculture established 121 trials in its Narrogin advisory district starting in 1972 to measure the effect of bulldozer and grader built seepage interceptor banks and drains on the topsoil salinity of the land downslope of them.

After 14 years of moniterin, there was no evidence that seepage interceptor drains and banks reduced the top soil salinity on 10 of the 11 sites in the Pingelly, Brookton and Wickepin Shires.

Salinity Control In Northern China, G A. Robertson

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

China has vast areas of saline land, perhaps as much as six million hectares. Some of this saline land is a result of marine influence in coastal areas and some is the resultof soil formation in areas with saline geological deposits and inadequate rainfall to leach out the salts at that time.

However, most saline soils in China are as a result of secondary salinisation processess induced by a hydrological imbalance resulting from over-clearing of the land or irrigation. This imbalance has produced rising watertables bringing the salt closer to the soil surface.

In this article, G..A. Robertson, Commissioner …

Effects Of Surface Drainage On Dryland Salinity, P R. George, T. R. Negus

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

Areas which are salt-affected are often also flooded. Although flooding is not the basic cause of salinity, surface drainage may improve conditions for plant growth, and this article describes suitable methods