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salt ISSUE No The Magazine of Australia’s National Dryland Salinity Program Personal stories of Australians combatting and learning to live with dryland salinity Productive, profitable solutions for dryland salinity magazine Home Home Welcome to SALT magazine initiative by having provided his is the fourth edimuch of the knowledge-base tion of SALT magazine upon which the Plan builds and it is difficult to The National Action Plan is sigcomprehend the changes nificant for a number of reasons that have taken place since First, it will direct the largest sum the first edition These of funds ever allocated by the changes have included major Commonwealth government government announcements specifically towards tackling dryand new programs at both land salinity nation-wide the federal and state levels; Second, it will allocate resources further revelation about the as block-funding against commuextent and nature of the nity-supported plans at a regional impact of dryland salinity Richard Price scale, overcoming past limitations Australia-wide; new industry of project-by-project support for and educational initiatives; small, unconnected activities and now a fresh new update of the format of Most significantly, however, it recognises that this magazine there is no one solution to dryland salinity, and At the time of the first edition of SALT magathat under some circumstances, the most effeczine, still less than two years ago, the majority of tive and profitable means of managing salinity is the messages about dryland salinity were largeto take a positive attitude towards utilising ly negative: War on Salinity! Battle Against the saline land and groundwater resources White Death! Salt Cancer of the Earth! So read SALT magazine is about sharing a positive attimany of the headlines of the time tude toward the problem In some cases, the Yet even then, many success stories were to be stories in SALT magazine are about the triumphs told Many others were taking shape Solutions in overcoming a salinity problem In others, it for dryland salinity exist in many circumis about preventing one, or adapting to one stances, and these solutions have been successThe new format and distribution of SALT magafully tried where it counts - in the field The zine is intended to widen the audience to ensure Grains Research and Development Corporation that more and more people become aware about and Land and Water Australia wanted to capthe triumphs; about the solutions ture these success stories, and developed SALT magazine as the appropriate means of commuOver the next few months, Australia's National nicating these stories Dryland Salinity Program will itself be adapting Since then, one of the most significant events to the changes that are taking place In addition has been the recent announcement of the Prime to changing the format of SALT magazine, the Minister's National Action Plan for Salinity and Program's Communications team will be Water Quality This Plan was endorsed by all improving our national, state and regional comstate governments at the November 2000 meetmunication effort Already we have appointed ing of the Council of Australian Governments new State Communication Co-ordinators in (COAG) The National Dryland Salinity NSW (Lisa Gray) and Queensland (Mark Program is proud to have contributed to this Warnick) T Kim Mitchell of Currie Communications has recently been appointed as the National Communications Coordinator over the remaining life of the current Program (to June 2003) Together with Bruce Munday (SA), Georgina Wilson (WA) and Jo Curkpatrick and Diana Wolfe (Vic), the new members of our team will add great value to the research, development and extension effort of the Program One final change to the management arrangements of the Program has been my appointment as the fulltime National Manager This role amalgamates the previous part-time Program Manager position, which I formerly undertook, with the part-time National Co-ordinator position, formerly undertaken by Nicholas Newland, and before him by Adrian Webb Nicholas has now moved on to take the helm of the South Australian Environmental Protection Agency and on behalf of the Program we wish him well While it is trite to say that change is good; it is more accurate to say that it is inevitable I look forward to the changes before us with a great deal of enthusiasm, and remain committed to ensuring that Australia's National Dryland Salinity Program and its partners remain a positive source of innovative and practical research solutions Australia's National Dryland Salinity Program is a partnership in research, development and extension tackling the salinity risk to Australia's land and water resources For further information about the Program, contact one of our Communication Co-ordinators (see page 23) or visit the NDSP website at www.ndsp.gov.au Richard Price, NDSP National Manager Any recommendations contained in SALT magazine not necessarily represent the policies of the National Dryland Salinity Program partners No person should act on the contents of this publication whether as to matters of fact or opinion or other content, without first obtaining specific independent professional advice which confirms the information contained in this publication Other contributors State Governments of WA, SA, Vic, NSW, Qld and Tasmania Editorial design & production: WDM Design & Advertising, Adelaide S A L T Home M A G A Z I N E Scald site helps spread the word on salinity Case study: Capricorn Coast Landcare Group Location: Hedlow Creek (via Rockhampton) Capricorn Coast Landcare Group, project to reverse the says combating dryland salinity effects of a major salinity involves communicating accurate scald on Yeppoon's information and practical solutions Capricorn Coast, Queensland, is to the broader community being used as an educational tool to She also co-ordinates 15 ecologicalreach landholders, councils, the ly-orientated community groups that community and school children hope to achieve environmental The salt scald, several hectares in size, action on a larger scale by pooling is in the catchment of Hedlow Creek, talents and resources For eight on Old Byfield Road, 25 kilometres months these groups have been from Rockhampton working on a publication for the Capricorn Coast Landcare Group Capricorn Coast region to help those became involved with the problem residents not normally environmenthree years ago where it lies adjacent to tally-minded to become aware of the saline Hedlow Creek trends and solutions in the area Group vice-president, Les Embrey, says Community interaction has included soil in the area has become very sodic a Giant Rats Tail Grass field day for and dispersible making it particularly landholders, a Waterwatch training prone to erosion and causing a number day for locals concerned about water of trees on a nearby property to die Chantelle James, Capricorn Coast Landcare and John quality, an environmental bus trip "A corridor of salt tolerant species of Fletcher, The Caves Catchment Management for councillors and managers from trees, shrubs and grasses have been Committee, keep tabs on a salinity scald in the Livingstone Shire Council and eduplanted near the salt scald to lower the Yeppoon area cating the younger community water table and give some ground through three junior Landcare cover," he says groups astically with the Landcare group and last year "The plants were propagated by Yeppoon State More workshops, field days and information the youngsters won the Shade and Spade Primary School's junior Landcarers group evenings are planned for 2001 This is typical Education Award for Arbour Day." "Pupils from the school have worked enthusiof the mentoring and empowerment work by As the vegetation grows it is expected to lower all Landcare and ICM groups across the water table and link up with nearby trees Queensland to form a wildlife corridor The content of these educational activities will The site has been used for Junior Landcare and be ascertained following analysis of results Council excursions and as improvements take received from a landholder survey conducted place it will be part of a remedial approach to in the area for the Capricorn Coast Landcare educate landholders and the community Group's Envirolink Project A bore-hole was sunk, allowing the group to ■ Conservation efforts on a major monitor the level of the water table and salt salt scald in the Rockhampton • Les Embrey and Chantelle James spoke with content on a monthly basis region has proven a valuable John Sanderson It is hoped that in the future landholders along educational tool Hedlow Creek will receive monetary assistance ■ Numerous educational activities to fence and revegetate riparian zones involving the site are assisting to Revegetation of ridge lines in the catchment CONTACT: improve community could also serve to lessen the movement of understanding of the salinity ■ Chantelle James, Envirolink Co-ordinator salts through the soil profile Future work will problem facing the region Ph: (07) 4939 1002 depend on trends in the figures Chantelle James, Envirolink Co-ordinator for A Key points T h e M a g a z i n e o f A u s t r a l i a ’s N a t i o n a l D r y l a n d S a l i n i t y P ro g r a m salt Home Farming with negligible recharge Case study: Philip & Diane Down Location: Meningie, South Australia Area: 1740 Average Rainfall: 450 mm Enterprise: Dryland dairy milking 450 cows; Holstein Friesian stud O ur attitude to salinity changed one night in 1988 We have hardly any salinity on our property, although it is certainly a very serious issue throughout the Coorong district At the Agricultural Bureau meeting that night, Steve Barnett, from what was then the Department of Mines and Energy, showed us a district map with the areas that were then salt affected He then presented hydrographs showing the rate at which saline ground water was rising and a map of where salinity would be in 20 years time Suddenly we could see that if nothing was done we could lose half the farm Steve pointed out that local recharge is important in our district as it feeds an unconfined aquifer which then puts pressure on a deeper confined aquifer This is highly saline and is being forced to the surface, so we all need to be doing our bit to arrest this trend When we got out of beef in 1982 we redeveloped the property, incorporating 20 kilometres of 60 metrewide laneways That did not work on our light sandy loams with cows walking long distances to the two dairies, so we decided to rubble 10 m and plant native vegetation in the other 50 m This took advantage of the fact that one side was already fenced and when finished we will have revegetated 100 hectares where previously nothing was growing The annual evaporation at Meningie is about 1000 mm greater than the annual rainfall, so the typical dairy pastures of rye grass and clover are not a prospect at all Our whole property is now under dryland lucerne of which we renovate 10 per cent each year We look after the lucerne by rotating stock through 12 paddocks to give the lucerne at least 21 days to recover, controlling weeds (mainly primrose and silver grass) and by attending to the known soil nutrient deficiencies Established lucerne is apparently just about as good as native vegetation in preventing ground water recharge As the lucerne gradually declines veldt grass takes over, so we always have perennial plants in the paddock, but the veldt is not nearly as deep rooted and so far less effective Lucerne underpins our whole operation, but we don’t like relying on a monoculture for something as important as ground water control, particularly after the devastation caused in the late 70s by the blue-green aphid and the salinity explosion that followed We have a 10-year plan to put a 24 m wide strip of native vegetation down the edge of every paddock we renovate This takes almost a hectare out of each paddock, but running S A L T Home M A G A Z I N E Key points ■ Ground water in the region is rising ■ Vigorous lucerne is very effective at minimising recharge ■ Native vegetation brings multiple benefits ■ The Local Action Plan has mobilised the whole district to recharge control ■ Sustainable farming is about longterm planning east-west it will not only reduce recharge, but also provide a very effective windbreak which is important as we are so close to the Southern Ocean We started our revegetation program in 1989, planting 3000 tubestock by hand We increased this to about 8000 per year using a tree planter, but it was still hard work involving two people At this rate we wondered if we would ever get to the end of our program In 1992 we tried direct seeding and had stunning results, despite pretty sloppy site preparation All of a sudden this huge goal we had set seemed achievable The next year we did everything by the book, except controlling the weather which was a shocker - hot and windy After days of crawling around on hands and knees trying to find a germinating plant we just about gave up, assuming that most of the seed probably blew away But enough eventually germinated to restore our faith that this really was the way to go These days we would not dream of anything other than direct seeding They might not all come up in the year they are sown, but eventually most of them appear You just have to be patient with nature Our seed mixture is based on a Opposite page: Well managed lucerne is the key to our productivity and watertable management Above: Direct seeded windbreaks will protect every paddock Below: Multiple local species help control the watertable and provide a biodiversity buffer to our agricultural system survey we did of nearby native scrub, so everything is local to the district We make sure we have good weed control and ground preparation and with experience we now generally get the timing right Rabbits used to be a problem, but the calicivirus seems to have reduced their numbers dramatically Hares have emerged as a more recent problem along with kangaroos Ironically the revegetation work has provided them with a haven and this is likely to get worse as we establish more of this Lucerne is obviously the key to productivity on this farm and in a good year like 2000 we can make about 600 tonnes of pit silage and 350 tonnes of hay It is also the key to our sustainability But the revegetation is also very high on our agenda When we started the redevelopment there was scarcely a tree standing on the property We have a long way to go, but it is already immensely satisfying to look around now and see where we have been The network of trees and shrubs now support birds we didn’t even know existed, along with all the other elements of biodiversity which make this a more sustainable farm The Coorong District is a landlocked catchment, so recharge reduction is about the only way to make sure the salinity problem does not overtake us One of the goals of the Local Action Plan is to reduce recharge by 50 pc over the 10 years from 1994 As part of the strategy to achieve that we have received Natural Heritage Trust (NHT) incentives to establish and manage lucerne and native vegetation This has certainly helped us maintain the pace of redevelopment and it has also encouraged lots of other landholders to get involved This is one of the largest dryland dairies in SA and we have to keep good quality feed up to the cows every day But we also have to take a long-term view and make sure that our management now ensures that we are still here to farm it in the future • Philip and Diane Down spoke with Bruce Munday, NDSP Communication Coordinator (SA) CONTACT: ■ Bruce Munday, Clear Connections Ph: (08) 8538 7075 Fax: (08) 8538 7075 E-mail: bcmunday@senet.com.au T h e M a g a z i n e o f A u s t r a l i a ’s N a t i o n a l D r y l a n d S a l i n i t y P ro g r a m salt Home Photos: Agriculture Western Australia CORRIGIN A town of windmills looks back for answers Case study: Corrigin Shire Council Location: 230 km east of Perth, WA Area: 3095 sq km Average Rainfall: 350 mm W indmills have long provided an image of security in rural Australia, and a new side to their value has been reinforced at Corrigin, a town of 1300 residents in Western Australia's wheatbelt region Until scheme water was connected for the first time in 1961, Corrigin's essential infrastructure included about 50 windmills and wells supplying water from deep below ground The proliferation of windmills even encouraged the brand name for the local flourmill and motel During the 1950s growing population and pressure on water supplies forced townspeople to deepen bores, and creating concern over diminishing supply But connection to the pipeline from Mundaring Weir in 1961 appeared to solve all the problems Like in so many towns, having unlimited water on tap brought rapid changes to residents' habits Within 10 years only two windmills were still in use, while invisible water tables were rising through the combination of extra water for lawns and gardens and less drawdown By the mid-1990s alarm bells had begun to ring Waterlogging was showing up in the south-west of the town; the hotel had to pump out water from its cellar; and small areas of salt about the size of a dining room table were appearing in the business district in late summer Shire president and local farmer David Abe remembers it well "In the early 1990s council organised for a heap of piezometers to be put down around the town," he says "By early 1996 they were indicating that water tables were only 1.5 to metres from the surface in some places "A few of us recognised the problem and we called a public meeting to work out what could be done A committee was formed that night, but it was hard to know what to do." Agriculture Western Australia in Northam provided some help but it needed a longer-term strategy When the Western Australian Government offered to help 13 towns with problems through the Salinity Action Plan from 1996-97, Corrigin made sure it was one of the first to raise its hand Understanding how to cope with town site salinity has grown substantially since, but many agree it has been a steep learning curve over the last four years Trees, offered as the primary tool, achieved little although some were planted in the first year, David says Airborne geophysics fly-overs also gave little result S A L T Home M A G A Z I N E Left: A water truck loads up with free water at the Corrigin stand pipe - exporting the problem out of the town site area and assisting nearby land owners But appreciating that excess water Recommendations for treatment now include a proposal to dehas to be pumped out and used on water the town site and reinstate a sufficient scale, is now helping the water balance much as it was Corrigin overcome its problems before arrival of the scheme water "Through the Rural Towns in 1961 Program, we have installed more "When Corrigin was the town of piezometers to monitor water levwindmills, each windmill pumped els," David says "We are very forabout 2500 to 5000 litres per day, tunate that the water is good qualremoving about 170,000 litres or ity and five bores are now pump170 cubic metres per day for ing non-stop into a 40,000 gallon drinking, washing and vegetable (182,000 litre) tank Three more and fruit tree irrigation," Mark bores will be connected before Corrigin Shire president and Rural Towns Program says committee member David Abe with one of the production summer is over." "But our analysis shows that once bores reducing water tables in the town The water cannot be sold by the the windmills were removed, the council, but is available for farmlevel of the aquifer below Corrigin ers to use for stock use and spraybegan rising at about 0.3 metres per annum ing, and for irrigating council and school It was only a matter of time before problems ovals Exporting water from the town is the began in the lower parts of the town." ideal option and one which no other town in Although the total cost of operating and mainWestern Australia has yet achieved taining pumping facilities has been estimated "A major cost is road works," David Abe says at $22,000 per year, the potential savings in ■ Excess ground water is being "Where the watertable is high - within 1.5 purchased water to the community are about pumped from beneath a town in metres of the surface - we can't compact the $38,000 per year at current costs the Western Australian Wheatbelt ground properly and the foundations collapse This is making it comparatively easy for region to manage waterlogging This is one of the council's biggest costs, but Corrigin to make the decision to invest in and reinstate the water balance one we hope to reduce from now onwards." groundwater pumping as its best salinity man■ Five bores now pump ground For the hotel, weekly cellar pumping had agement option and turn a liability into an water non-stop into a 182,000 litre asset become a regular part of life But resurrection tank for the community to utilise of an old bore 40 metres away enabled the • David Abe and Mark Pridham spoke to owners to forget pumping - until the casing Georgina Wilson, NDSP Communication collapsed Connecting a new bore is now a priCo-ordinator (WA) ority, but the effects of other bores have helped unique position of being able to take the Key points reduce pumping to every six weeks, even without the closer one Thirty towns in WA are now participating in the Rural Towns Program administered by Agriculture Western Australia, under which costs are shared equally between local councils and the program Program manager Mark Pridham says Corrigin was one of the lucky towns because of its source of the problem - excess groundwater and turn it into a resource This was possible because of the good quality of the water under the town and its location away from the flat valley floors During 2000 the economic impacts of salinity on town site infrastructure were assessed A range of control options which included pumping groundwater were also evaluated CONTACT: ■ David Abe, Ph: (08) 9063 2263; Mark Pridham, Agriculture Western Australia Ph: (08) 9368 3919 T h e M a g a z i n e o f A u s t r a l i a ’s N a t i o n a l D r y l a n d S a l i n i t y P ro g r a m salt Home Photos: Jo Curkpatrick PAKENHAM GOLF COURSE Reclaiming the greens — naturally T he Pakenham and District Golf Club looks a picture The greens and fairways are well covered with grass, the trees are growing well and the golfers are out in force As Course Superintendent Anthony Wright told Victoria's NDSP Communications Co-ordinator (and enthusiastic golfer) Jo Curkpatrick, the course today looks a lot different than it did 10 years ago When the Pakenham course was established back in 1985, it was built on a floodplain covered in Melaleuca ericafolia A lot of these trees were removed to build the golf course, but without a plan for managing the water, the effects of salinity start- ed to show up very early on We have tackled the problem by improving the soil balance to deal with the high sodium levels in the soil Our approach has been to address the problem, not to apply a 'bandaid' By getting a good balance in the soil we have been able to show a big improvement in the cover on the fairways With better soils and good grass growth we have also been able to utilise effluent water in our irrigation program and that wouldn't have been possible a few years ago The inspiration for our approach has been William Albrecht, an American soil scientist in the 1940s and 50s Albrecht had taken soil samples around the S A L T Home M A G A Z I N E Left: Pakenham Golf Club superintendent Anthony Wright and Kirsten Barker, salinity officer (DNRE) for the Port Phillip region, look over one of the club’s greens Right: The state of the course before (top) and after (below) the club’s extensive restoration work world and determined that there was a common thread for fertile soils in terms of the levels of calcium and magnesium in the soil We started with a soil that had pH of with high levels of sodium and sulfur In earlier days gypsum was being added but that was making the problem worse By meeting Albrecht's balance for calcium and magnesium and by adding calcium and potassium, the pH has improved and we have been able to grow good grass on the fairways and greens Some of trees on the golf course were suffering from the high salt levels, so we went back to planting M.ericafolia and swamp gums (Eucalyptus ovata) and they are doing much better than trees from outside the area We have planted about 4000 trees so far We use mostly organic fertilisers and haven't used insecticides or fertilisers for two years I would like to have the first certified completely organic golf course in Australia, but so far we haven't found a way to control weeds such as paspalum without herbicides Our main fertiliser is chicken litter from an organic poultry shed nearby We spread it annually on the fairways Soil testing is undertaken once a year on the fairways and quarterly on the greens which allows us to keep a pretty close watch on fertility levels and tells us when some intensive treatment is required It's not that hard to and the rewards are there We have saved money on insecticides and fungicides and put the savings back into fertilisers It costs about $1000 per fungicide application and that's a lot of money for a small club like ours Besides, by not using insecticides we are noticing that the native birds have begun to return We still have a drainage problem and the golfers will tell you it gets pretty wet during winter But we can't flush or pump out the excess water because there is no where for it to go A quote to re-shape and drain one fairway is around $75,000 and that is out of our reach You can't beat good drainage, but by tackling the soil chemistry we can make a difference We also match our irrigation with evaporation and tend to err on the side of not enough water Kirsten Barker, our local salinity officer from the Department of Natural Resources and Environment is keeping an eye on water table levels She reports regularly on levels in monitoring bores on the golf course and in the nearby residential area We have noticed a fall in the water table, but with several dry years it is hard to accurately pin down the reasons What we know is that about 2000 hectares of discharge have been mapped in the Western Port catchment and there is sure to be more than what has already been mapped It really hasn't been that difficult or expensive and the proof is in the pudding We have a better golf course for our members and in 1999 the Cardinia Shire recognised our efforts with an Environmental Management Award Key points ■ Dryland salinity is evident on the fairways of an 18-hole community course located south-east of Melbourne ■ Average rainfall 790-820mm ■ Salinity problem is being overcome by improving the soil balance using organic fertilisers; irrigating with effluent water and planting salt tolerant grasses (Santa Ana Couch), improving turf conditions significantly CONTACT: ■ Anthony Wright, Pakenham and District Golf Club Ph: (03) 5941 2929 T h e M a g a z i n e o f A u s t r a l i a ’s N a t i o n a l D r y l a n d S a l i n i t y P ro g r a m salt Home Groundwater pumping is proving its worth A third of our property Case study: Robert and Helen Nixon had the potential to go and family saline and now after Location: Kalannie, WA more than five years of pumpArea: 7000 ing, we have turned the corner and are progressively reclaimAverage Rainfall: 300 mm ing about 200 hectares Enterprise: grain and sheep Here at Kalannie, my father and uncle saw the first signs of salinity in the 1960s after land clearing began in 1925 In the early 1960s they were We must use the appropriate mix of land renosuggesting that pumping with windmills would vation weapons in the war against salt be necessary But it's only in the last five or six Drainage is essential in our valley floors where years that we've really got into pumping seri- there is a huge volume of groundwater that is more saline than sea water ously, although we've tried other treatments 10 Oil mallees and lucerne are used in the valley slopes to extract perched groundwater, but in the valley floors, pumping is the engineering solution used to extract the more saline water In 1994 I was talking to Ramsis Salama from CSIRO about their salinity research, and he recommended I a cost-benefit analysis as a starting point We tried to get funding from many places, but although we were short-listed a few times, we were never successful S A L T Home M A G A Z I N E Left: Colin Walker from Murdoch University downloads meteorological data near proposed evaporation ponds We gained assistance from Colin Walker at Murdoch University and established a self-funded research and development project Farmers like us with salinity problems on land in the lower valley floors are very frustrated that there is no public money for engineering solutions This is usually our prime land - the champagne country How much of my property was affected is hard to tell Salt on valley floors is insidious Only a small percentage of the land is totally lost, but much larger areas lose fertility and capacity for production as the water tables rise For the research project we installed the first extraction and monitoring bores in 1995 and began pumping once approvals had been granted About a third of our time and considerRobert Nixon logging one of the 50 boreholes able investment has occurred over five years Altogether we installed 52 groundwater monitoring bores, three have been bunded (given retaining banks) to water extraction bores and more than 10 km of provide evaporation and crystalliser ponds for water lines salt production We had a long-term plan to acquire land with We planned to harvest salt, but this has been salt lakes for disposal of the water Saline water very limited due to unexpected rain in the last is pumped km to these lakes, some of which two summers We had four inches of rain dur- Key points ■ Pumping is pegging back water tables in WA ■ Cost-benefit analysis has ensured economics of Landcare activity ■ Land reclaimed, increased production and saleable salt ing January making it impossible over this period In February you would normally expect the place to look completely brown, but in fact it is green The three production bores yield 450,000 litres a day all year round The main costs now are electricity and maintenance on the system as we continue pumping People in this area are very conscious of Landcare My neighbours and the LCDC have been very helpful and supportive Richard George and others from Agriculture Western Australia have been a sounding board for ideas, and various groups have visited the project The highlight for us has been the effects near the homestead You can see it in the native on his Kalannie, WA, property vegetation 500 to 800 metres from the first production bore As the salt encroached, the canopy of the trees became stunted with lots of dead wood Now the canopies are rising progressively through the dead wood branches When you start drainage work like this on a problem that has developed over 75 years, changes won't happen overnight First, you have to stop it getting any worse and then begin to peg it back Reversing the effects of half a century is going to take more than a couple of years, but we have certainly made a start • Robert Nixon spoke with Georgina Wilson, NDSP Communication Co-ordinator (WA) CONTACT: ■ Georgina Wilson, Agriculture Western Australia Ph: (08) 9368 3889 Fax: (08) 9474 2018 E-mail: gwilson@agric.wa.gov.au T h e M a g a z i n e o f A u s t r a l i a ’s N a t i o n a l D r y l a n d S a l i n i t y P ro g r a m salt 11 Home Making the most of saline ground Case study: Malcolm Schaefer Location: Kangaroo Island, South Australia Area: 1200 with a further 400 leased Average Rainfall: 550 mm Enterprises: Wool, prime lambs, oats and vetch S Serradela on a non-wetting sandy rise treated with clay 12 alt has always been evident in these parts of Kangaroo Island, which is hardly surprising since we are only a few kilometres from the Southern Ocean Clearing commenced on our property in 1904 and continued up until about 1950, even though some parts of the land were obviously salt affected I remember my father saying that the land almost asked to be cleared because the main vegetation type was tea-tree which was very easy to clear I realised that the salinity problem was getting dramatically worse in 1984 after a very wet year That was when I started a small program of planting salttolerant grasses and trees on affected areas In those days, with not much experience to fall back on, it took several years to thicken up the grasses and most of the trees (which cost $2 each) were eaten by kangaroos Another wet year in 1992 saw the salt spread even further, many more old trees died and I could see that the problem had now become urgent About one third of my land is salt affected, another third is non-wetting sand and the remainder is good cropping land Because I am at the landlocked bottom of a large groundwater system, there is not a great deal I can about lowering the watertable I can probably protect assets like dams with targeted local revegetation, but I also need to protect the land that is not salt-affected and live productively with the land that is A major breakthrough occurred when I attended a local Landcare conference in 1994 and saw the opportunities for direct seeding of native vegetation Not only can large areas be sown quickly, the 'roos don't seem to find this as attractive as the tubestock As my farm is bounded on three sides by native vegetation I have an abundant seed source as well as an abundance of kangaroos Preparation for direct seeding consists of spraying 700 mm wide strips with glyphosate in June and then again about five weeks later to kill the second germination of weeds Seeding is done in August, but germination seems to be staggered over the next 12 months depending on the weather conditions, so it does not really matter much if we have a dry spring and there is not much to show for awhile S A L T Home M A G A Z I N E Dundas tall wheat grass in the middle ground with puccinellia in front and behind In 1995, I visited the Upper South-East region of SA to look at clay spreading to overcome non-wetting sands While I was there I also saw the dramatic impact of fertiliser on salt tolerant pastures Their swards were much more productive than I was used to, and by sowing tall wheat grass and puccinellia separately they were also able to reap their own seed After a number of small trials and having seen the results in the Upper South East, I have now developed a good system for establishing puccinellia and tall wheat grass: • Spray top in spring to remove barley grass • Three weeks after the opening rain, spray with glyphosate at 800 ml/ha • Scarify, then sow pasture seed at 8-10 kg/ha through a combine, just dropping the seed on the surface and covering with combine harrows • Fertilise with 60 kg/ha plain super and spray for red legged earth mite • Lightly roll, mainly to prepare the paddock for seed harvesting • Because our land has such light relief I put in shallow surface drains to minimise waterlogging • In late August I apply urea at 50 kg/ha I am now using the new pasture variety Dundas tall wheat grass which seems to have a much better growth habit, being far less 'clumpy' than the traditional variety Tyrell In March I can reap both the puccinellia and the tall wheat grass so that I am pretty well self sufficient in seed even as I expand my planting The reaped paddocks provide excellent clean grazing for drenched sheep as they have Key points ■ There are real opportunities to use saline land productively ■ Managing saline land productively is relatively 'new territory' ■ There is much to be learned from others who are also dealing with salinity on farms not been grazed since the previous September So far I have established about 60 hectares and I have spraytopped a further 120 to be sown this year, reflecting the confidence I now have in the system This program has been accelerated because we have temporarily destocked the home farm whilst Ovine Johne's Disease is being eradicated Last year I did some trial work spreading clay on non-wetting sands With technical support from PIRSA staff at Kingscote I have trialled several rates of clay ranging from 50 to 200 t/ha and five different pasture species: veldt grass, serradella, biserrula and two varieties of lucerne Each established quite well, with the serradela (a very acid-tolerant legume) producing a great amount of bulk Given that these sands are usually bare, erodable and significant sources of recharge, it will Photos: Bruce Munday be a real step forward if I can get good productive growth there This year I will be sowing 40 of lucerne on non-wetting sands that have been ameliorated with clay The other resource I am really keen to protect is my surface water Even on the relatively elevated land I have dams which have 'gone salty' as a result of surface salt appearing in the drainage lines By fencing off a couple of hundred metres leading into the dam and planting trees and shrubs I have been able to keep this local salt down A dam which registered 13,000 mg/l at the end of summer before planting now has a salinity of 8500 mg/l at the same time of the year Over the years I have learned a lot about managing salt and I am now confident that I am working towards a pretty good system Lots of trial and error, looking at what others are doing, support from PIRSA staff and NHT incentive payments have all helped to get me to a situation where I can manage my saline land productively and protect my good land • Malcolm Schaefer spoke with Bruce Munday, NDSP Communication Co-ordinator (SA) CONTACT: ■ Bruce Munday, Clear Connections Ph: (08) 8538 7075 Fax: (08) 8538 7075 E-mail: bcmunday@senet.com.au T h e M a g a z i n e o f A u s t r a l i a ’s N a t i o n a l D r y l a n d S a l i n i t y P ro g r a m salt 13 Home How much does the crop leak? M ost farmers are aware that annual crops 'leak', contributing water to rising groundwater systems However, this leakage has been difficult to measure without sophisticated equipment This is about to change and grain growers will soon be able to monitor the moisture that drains past the root zone of shallowrooted crops and other crops and pastures Dr Paul Hutchison, CSIRO Land & Water, explains: The breakthrough in soil moisture measurement is a simple drainage meter which we have developed with support from growers and the Federal Government through the GRDC The information gained will be very valuable on two fronts - it will show if a farming system is 'leaky' but also whether a deeper-rooted plant can be sown to take advantage of the moisture at depth More and more farmers are looking to turn moisture at depth into profit by sowing for example, a vigorous perennial pasture such as lucerne and using it for prime lamb production, or growing summer-active crops such as sorghum and millet The drainage meter has two versions - one costing about $600 for research purposes and a cheaper version, about $300, for use by farmers and extension personnel A schematic of the research version is shown in Figure The instrument consists of a long open-topped tube (1) that is filled with silica escape so a water table forms Changes in the powder At the base of the tube there is a caviwater table height are measured with the presty (6) that is separated from the silica by a fine sure transducer and recorded with a data logmesh (5) This cavity is connected to the surger at the soil surface face via a drain tube (3) and vent tube (2) At In the manual version of the the base of the cavity is a drainage meter currently differential pressure sensor under development, the (7) that is connected to the pressure transducer will be surface via a cable (4) replaced by a dipstick to The meter is installed by reduce the cost A hollow, first auguring a five-cenporous ceramic rod also timetre diameter hole (8) to replaces the silica powder a depth equal to the height When a measurement of of the meter (1.4 metres) deep drainage is required plus the distance below the the dipstick is removed from soil surface where the the hollow rod by pulling on measurement is required a cable from the surface The In the case of wheat where height of the water table is roots are generally in the then recorded and the diptop m, the hole is drilled stick replaced Installation of to a depth of about 2.5 m the dipstick model is the The hole is then widened Figure 1: Annual crop same as for the research verto 10 cm from the surface 'leakage' is being sion to a depth of the measuremeasured using new, costBy measuring the water table ment height plus 20 cm effective technology two or three times from The meter is then installed autumn to spring, you know and a heavy clay (8) is whether drainage is occurpacked below the top of ring and whether to change a rotation to say, the meter to prevent entry of water Next a silinclude lucerne Where long fallows may be ica tip (9) is packed followed by a further layer contributing to recharge, this can also be measof heavy clay (10) The final material packed ured and a farmer would know if he has to into the hole is topsoil (11) swing back into cropping as soon as possible As moisture moves past the silica tip, it is Early results are showing that the drainage drawn by capillary action through the silica meter can measure soil moisture as well as a powder into the tube The moisture cannot Lucerne a profitable switch F armers in Western Australia continue to turn to lucerne for its versatility in high water use farming systems Just how versatile and profitable it can be was portrayed at the recent Lucerne 2000 Symposium, held in Katanning in the southeast of the State with support from the Federal Government and graingrowers through the Grains Research and Development Corporation (GRDC) Growers from various parts of the Wheatbelt shared their experiences and painted an impressive picture for the role the deep rooted perennial legume can play as a profitable rotation tool for lowering watertables After a trip to Montana, USA, to study lucerne, Dumbleyung farmer Jeff Patterson is convinced the perennial will take him a step closer to his goal of sustainable, profitable farming "My experience has strengthened my resolve to direct Landcare away from potentially damag- 14 the 1970s to use summer rain ing drainage schemes and and supplement sheep feed, an focus, instead, on high water emerging salinity problem use sustainable farming," he prompted him to turn to lucerne says for broadacre watertable control With a lucerne-based pasture - and it has succeeded doing its work on the Annually sowing 200 hectares, watertable, Jeff hopes to with 800ha of the property curreduce the dependence he has rently planted, he has developed on his cropping enterprise, a fine-tuned lucerne establishwhich currently generates 80 ment and management system per cent of the farm's income that has boosted the efficiency of To that, he plans to devote Bill Fraser, pictured both the cropping and livestock half the property to lucerne at his Quairading enterprises within the next two years, farm during a recent "We've made some changes to using it as a four-year pasture GRDC salinity tour accommodate lucerne, such as phase in an eight-year cropmoving from set stocking to rotaping rotation tional grazing so we can spell it for five to six Jerramungup farmer Geoff Bee already has weeks recovery," Geoff says 'runs on the board' when it comes to success "We've also increased the size of the sheep with lucerne mobs, so we can adequately stock paddocks, After originally planting small hobby blocks in S A L T Home Paul Hutchison (right) demonstrates the drainage meter near Harden, NSW much more complex and expensive mercury tensiometer The drainage meter can be completely buried below the cultivation layer and needs no maintenance, compared with a tensiometer which sticks up in the paddock and needs regular attention We expect that growers will find this a particularly useful and practical tool It is very difficult to improve the water use of farming systems unless you know how it responds to management practices This tool removes the guesswork One landowner group particularly interested in drainage is the Harden-Murrumburrah Landcare Group in southern NSW Last year one of the research versions of drainage meters was installed in a paddock in the area where the group and CSIRO has, for some time, been conducting tillage treatments In this case, measurements were made of drainage under a wheat crop grown on two different treatments - one where stubble has been burnt and the soil cultivated and the other where conservation farming techniques are practiced, including stubble retention During the 2000 growing season about 30 mm of drainage was recorded in the 'burn and cultivate' treatment, and 100 mm in the 'conservation farming' treatment We attribute the three-fold difference to a number of causes including the fact that the surface soil in the burn and cultivate treatment has become sealed and some of the water runs off rather than into the soil This is not the case in the stubble retention treatment where the soil is also better structured facilitating water movement The co-ordinator of the HardenMurrumburrah Landcare Group, Louise Hufton, says: Landowners in this 250 member group are particularly interested in finding M A G A Z I N E out what farming systems contribute more than others to deep drainage About three per cent of the land in the Jugiong Creek Catchment, in which the group operates, is affected by salinity in lesser or greater degrees and the area of salinised land is increasing We want to install a series of meters across the catchment to test as many variables as possible Is there more leakage under wheat than there is under, say, canola, lucerne, perennial pastures or annual pastures? We want to also know the effect of vegetation adjacent to a crop on drainage It's all about finding systems that use available water, reduce salinity and increase production so perhaps there is scope for more lucerne in farming systems, for alley farming, or for crops that use more water in winter • Based on an article by Bruce Munday in the January 2001 edition of 'Focus on Salt' and subsequent interviews with CSIRO Land and Water scientist, Paul Hutchinson, and the co-ordinator of the Harden-Murrumburrah Landcare Group, Louise Hufton, by GRDC communicator, Denys Slee CONTACT: ■ Paul Hutchinson , CSIRO Land and Water Ph: (02) 6960 1558 Louise Hufton, Harden-Murrumburrah Landcare Ph: (02) 6386 8218 for groundwater management and have moved from short rotations to a phased rotation" After some testing early experience establishing lucerne, Central Wheatbelt farmer Bill Fraser, Quairading, has persisted and now intends using it as the base for all his pastures He sees lucerne as a way to solve rising watertable problems, while being able to produce more and higher quality wool, meat, barley and wheat, all at lower costs Bill began to invest in lucerne in 1998, when he set up his seeding bar to establish lucerne with cereals on an intermittent row system one lucerne row, one cereal row and one lucerne, for example "Our thinking was, and still is, that with financial constraints we could not forego a year's production to establish lucerne over the large areas necessary to have an impact on watertables and salt," he says While lucerne has helped increase productivi- ty of many grain, wool and meat enterprises, improving meat production is the clear focus of Kojonup farmer and consultant John Young Having implemented the simulation model MIDAS (Model of Integrated Dryland Agricultural Systems), John believes it is the meat side of the enterprise that will reap him the highest reward from lucerne Results from his analysis indicate grazing lucerne for a prime lamb flock increased profits by $75 for each hectare grown, compared to an increase of only $32/ha for wool production "We now plan to increase the lucerne area to about 20 pc of the farm, and believe with correct management, we can effectively fatten sheep on it," he said Professor of Agriculture at the University of WA, Phil Cocks, said lucerne could play a far more significant role in combating WA's $190 million worth of production lost each year from waterlogging and the additional $40 million from the related salinity problem Opening the Lucerne 2000 Symposium, said he was confident lucerne could control and manage rising water tables, while maintaining agricultural production, over at least two million hectares in WA The proportion of the remaining 10 to 12 million hectares which is suitable to lucerne is as yet unknown, he says Professor Cocks says a well managed lucerne pasture, with its deep roots, used more water than a well managed annual pasture and increased out of season pasture production "Our research shows that lucerne will also accumulate similar soil nitrogen and produce at least similar grain yields and protein in the following crop as annual pastures would do," he says "The challenge now is to reduce losses in the lucerne establishment year, by developing successful cover cropping techniques." • Story and photo by Brendon Cant T h e M a g a z i n e o f A u s t r a l i a ’s N a t i o n a l D r y l a n d S a l i n i t y P ro g r a m salt 15 Home PREVENTION Retaining vegetation to discourage salinity in Queensland L Photo: CSIRO Land & Water Retention of significant tree cover serves as long-term protection against dryland salinity In cleared areas at risk of dryland salinity, alternative crops such as this plantation of Tea Tree (Melaleuca alternifolia) at Mutchilba in Queensland can provide profitable solutions for managing the salinity risk Researchers with the Queensland Department of Natural Resources and Mines continue to develop salinity risk assessments across the State Risk assessments raise awareness about potential problems and indicate areas where changes to current practices are necessary to prevent or limit the development of salinity 16 andholders are being encouraged to retain native vegetation in key parts of the Queensland landscape to lessen the chances of developing long-term salinity problems Queensland Department of Natural Resources and Mines senior soil scientist, Ian Gordon, says preliminary investigations indicate that hundreds of thousands of hectares of farmland in Queensland were potentially at risk of salinity degradation in the next 30 years However, some areas might take 100 years to be salt affected This includes 600,000 recently identified as "at risk" in the Murray Darling Basin within Queensland "It is a bit like the risk of getting skin cancer Prevention is far wiser than merely covering up when the spots appear," Ian says "The retention of significant tree cover serves as long-term protection against dryland salinity Risk maps being compiled by DNR scientists show we need to take action now "Ten years ago DNR extension officers estimated that salinity severely affected 10,000 and about 75,000 was at risk "Today the area at risk has blown out to more than 500,000 in the Queensland section of the Murray Darling Basin alone An additional and more critical concern is the potential impact of salinity on water quality in our river systems." Ian says land was considered at risk of dryland salinity if the removal of vegetation was likely to raise water tables to within two metres of the surface without necessarily converting it to severely salt-affected land Evidence of salinity outbreaks was expected in up to 30 per cent of the area identified as 'at risk' In addition to impacts on land and productivity, the other effects of salinity included salinity levels in rivers and groundwater supplies, S A L T Home M A G A Z I N E Photos: Queensland Department of Natural Resources and Mines Queensland Department of Natural Resources and Mines soil scientist (salinity), Rachael Zischke, Indooroopilly, gathers information at a salt scald which has killed grass and gum trees near St George damage to infrastructure such as buildings, water supplies and roads, and ecosystems dependant on fresh water supplies Ian says DNR scientists based at the Department's Resource Sciences and Knowledge, Indooroopilly, will provide estimates on salinity risk for catchments in southern Queensland as a component of the National Land and Water Audit by mid-June this year On-going work would refine the preliminary estimates of salinity incorporated in the Murray Darling Basin Catchment Salinity Audit report completed in October last year In addition, salinity risk assessments for other parts of the State would be revised in parallel with this work "Risk maps are expressed in terms of the potential for land use changes, notably tree clearing, to turn this risk into an environmental problem," he says "Scientists are investigating to what extent change in land use will turn a high risk catchment into a long-term problem." Ian says as with the skin cancer analogy, science had discovered at least a 30-year delay in catchments responding to tree clearing "Thirty years is a relatively quick response in hydro-geological terms but catchments with even longer responses offer the real opportunity for the introduction of preventative actions," he says "The fact that Queensland has many catchments with heavy clay soils and summer dominant rainfall means the response time may take hundreds of years to show salinity degradation fol- lowing a change in land use." The rise of salinity was symptomatic of current land use practices that had replaced natural systems, he said "The resulting massive hydrological imbalance may take several hundred years to stabilise," he says "Dryland salinity is a result of rising water tables driven by the additional water moving beneath cropping and grazing systems compared to uncleared areas." Ian says deep drainage was a lost opportunity to produce crops and pastures because the additional water had moved below the root zone of agricultural crops Recent studies on the impact of land use change on salinity had been undertaken in the Queensland Murray Darling Basin catchments and programs were being developed to fast track recharge and salinity studies across the state "DNR will begin these studies in areas where vegetation clearing issues are of most immediate concern, which include the brigalow belt, mulga woodlands and desert uplands," he says "This is a broad risk assessment utilising geographic information systems (GIS) technology and will provide information at the catchment level Further assessment will be needed to provide information for property level decisionmaking." Ian says risk assessments raised awareness about potential problems and indicated areas where changes to current practices would be necessary to prevent or limit the development of salinity • Ian Gordon spoke with John Sanderson The rise of salinity in Queensland, such as this salt-affected area in the Boonah district, is symptomatic of current land use practices that have replaced natural systems Key points ■ The area at risk of salinity in the Queensland section of the Murray-Darling basin is now estimated to be more than 500,000 ■ Queensland catchments with heavy clay soils and summer dominant rainfall may take hundreds of years to show salinity degradation following a change in land use ■ Risk assessment studies are being undertaken at catchment level to determine the impact of land clearing on salinity, particularly in the brigalow belt, mulga woodlands and desert uplands CONTACT: ■ Ian Gordon QDNR Ph: (07) 3896 9471 T h e M a g a z i n e o f A u s t r a l i a ’s N a t i o n a l D r y l a n d S a l i n i t y P ro g r a m salt 17 Home C apella is 300 kilometres west of Rockhampton and 800 km northwest of Brisbane Located on the edge of the Central Highlands, soils vary from gently undulating plains formed on tertiary basalt shales or sandstone Grasses vary from Queensland bluegrass, black speargrass, barley grass, some Mitchell and Flinders grasses Thanks to strategic revegetation and adoption of new farming technologies local landholders Murray and Trish Brimblecombe have largely beaten a salinity problem, however it didn't seem that way back in 1985 At first we were a bit startled when one of the cultivations on our 3100 hectare property developed a bare patch where crops refused to grow No other landholders around here had heard of salinity problems of this extent At the start the degraded patch was the size of two four-wheel drive vehicles however over about three years it grew to about two hectares We contacted Ken Dixon, Soil Conservation Officer, and Bill Wilkinson, Senior Project Officer, Department of Natural Resources and Mines, DNR, Emerald, 100 kilometres south of here, and they did some soil tests and identified it as a salinity problem Previously black tea tree had been growing in the area It wasn't long before surface water began seeping out of the ground It looked brackish and had a salty taste DNR oversaw a tree planting operation on mounds of soil, because nothing would grow in the salt laden black soil In 1991, approximately 1000 trees, mostly salt tolerant, were planted in 40 cm high mounds of soil, pushed up at five-metre intervals on the contour The young plants were mulched and watered regularly At the time Queensland was entering a severe drought This allowed rainfall to leach the salts out of the surface soil, permitting native grasses and young trees to re-establish Slowly but surely the water table began to recede Native grasses began to grow back of their own accord and today we have good ground cover and a healthy plot of trees, many of them 18 RE-VEGETATION Targeted trees keep salinity at bay Case study: Murray and Trish Brimblecombe Location: Capella, Qld (300 km west of Rockhampton) Area: 3100 Enterprises: Livestock and cropping above seven metres in height My experience sends the message to all Australian landholders, that no matter what your location, you have to be awake to the signs of salinity, high water tables and subsequent management that is required This experience has made my wife Trish and myself more aware of natural resource management and our property has had several groups visit for workshop and field day purposes Before the salinity experience we were leaning towards stubble mulch farming and starting to zero-till with our cultivations Now all our country is contoured and zero tilled as much as possible We have been mindful of leaving stands of vegetation for rocky outcrops, to shade our livestock and shelter wildlife DNR saw it as a good opportunity to test the effectiveness of planting a variety of trees to lower the watertable On a cautionary note, Ken Dixon says saline seepage areas in the Central Highlands, which may have dried up in recent years, could reappear if prolonged wet conditions occur Seepage areas can be caused by clearing upper catchments or areas of black tea tree, which generally indicate a high watertable DNR has found that occasionally, as in our case at Capella, seepage can occur when geological reasons prevent water from moving downwards and force it to move sideways, through the soil profile, sometimes to the surface A variety of trees were planted to gauge their effectiveness at lowering the water table The trees were healthy and had achieved consistently high growth rates River red gum had an 80 per cent survival rate, compared to coolibah 69 pc, blackbutt 58 pc, Queensland white gum 60 pc, tipuana 38 pc and yapunya S A L T Home 16 pc After seven and a half years the blackbutt reached the greatest average height at 9.1 metres whereas the tipuana averaged out at 3.2 m There was no evidence of salt damage Initially some people believed the trees would eventually kill themselves by concentrating salts in the root zone but this hasn't happened Most tree deaths occurred at the seedling stage soon after planting There have been very few deaths in the last seven years Monitoring of both trees and soil is continuing Chloride levels of the surface soil have dropped by an average of 95 pc in both the mounded and inter-row areas The watertable has dropped allowing rainfall to leach salts lower into the soil profile enabling the return of native grasses such as bluegrass, wiregrass and windmill grass The seepage area has stopped spreading but high chloride levels below 50 cm suggest that if the trees were removed, the salinity outbreak would re-occur • Murray and Trish Brimblecombe spoke with John Sanderson CONTACT: ■ Ken Dixon, QDNR Ph: (07) 4987 9321 Key points ■ A targeted revegetation program and adoption of no-till farming practices are being used to manage a salinity problem near Capella, Qld ■ Chloride levels of the surface soil near the saline area have dropped by an average of 95pc in both the mounded and inter-row areas of revegetation ■ A lowered watertable has enabled the return of native grasses such as bluegrass, wiregrass and windmill grass Education is crucial to beating salt problem Photo: John Sanderson Left: With the assistance of Ken Dixon, Soil Conservationist, Queensland Department of Natural Resources, Emerald (right), Murray Brimblecombe, 'Mt Lowe', Capella, has largely eliminated his salinity problem M A G A Z I N E Queensland Department of Natural Resources and Mines technical officer (Groundwater Hydrology), Ashley Bleakley, Ipswich, inspects salt-encrusted soil in the Lockyer Valley with University of Queensland Gatton students Amy Kingston, Ipswich, (left) and Alison Rodgers, Toowoomba A salt scald, visible in the background, has killed off all of the vegetation L ockyer Catchment Co-ordinator Andrew Davidson says the Lockyer region has been identified as a target catchment under the recently announced National Action Plan for Salinity and Water Quality (NAPSWQ) Only a small percentage of the Lockyer Catchment in south-east Queensland is directly affected by salt, however the potential exists for a greater impact Lockyer Catchment contains large areas of marine sediments harbouring a significant salt load Landcare and Catchment Groups have long recognised the potential problem and worked with the community to raise awareness and coordinate positive actions to manage salinity Revegetation of the upland areas with deeprooted annuals and sustainable management of irrigation water have been priority actions The management of the large areas of existing vegetation in the uplands is also important Support and incentives for landholders to maintain these valuable areas of native vegetation have been the focus of much activity and lobbying by Landcare and catchment groups The Lockyer Watershed Management Association - Lockyer Landcare (LWMA) has also been very successful over the past 20 years in rehabilitating a number of the areas already affected by salt It has produced fact sheets that not only describe management practices and ‘best bet’ species for rehabilitation but also describe the land management practices that lead to salinity The sites are used to show landholders and visitors the damage salt can as well as the positive actions that can be taken to reclaim salty areas The Lockyer Catchment Co-ordinating Committee (LCCC) is now in the process of developing a salinity management plan for the catchment as a lead up to the NAPSWQ The LCCC has long promoted sustainable land use through land use planning handbooks and by closely working with councils to incorporate integrated catchment management into planning schemes This lead role by Landcare and catchment groups in partnership with the community, government and industry is set to continue under the NAPSWQ • Andrew Davidson spoke with John Sanderson CONTACT: ■ Andrew Davidson, Lockyer Catchment Co-ordinator Ph: (07) 5465 4822 T h e M a g a z i n e o f A u s t r a l i a ’s N a t i o n a l D r y l a n d S a l i n i t y P ro g r a m salt 19 Home ALTERNATIVES Future landscapes to fight salinity I Photos: CSIRO Land and Water Agroforestry potential: native forest near Pemberton, WA n the future when you travel through rural Australia, the scenery might look rather different The landscape of tomorrow is likely to be more leafy, shady and biodiverse and what is more, this peaceful countryside might also be our greatest weapon in the fight against the threat of rising salinity Land management techniques to combat salinity, both current and future, are presented in a new publication produced by CSIRO Land and Water to help farmers and land managers in the Murray-Darling Basin The report, A Revolution in Land Use: Emerging Land Use Systems for Managing Dryland Salinity, discusses a range of techniques including phase farming, companion farming, new crops, perennial pastures, tree crops in high and low rainfall areas, agroforestry and saltland farming Dr John Williams, Deputy Chief of CSIRO Land and Water and one of the authors of the publication, says that the goal is to limit water leakage past the root zone to a level something like that of the native vegetation This requires a big change in land use: a new landscape made up of a mosaic of commercial tree crops, mixed perennial-annual cropping systems and areas of native vegetation New rural industries that use perennial plants and trees, many of them Australian natives, can be developed to fight salinity As well as controlling the effects of salinity, these verdant future landscapes will help to protect Australia's biodiversity But before this vision can be realised, much more research is needed to develop suitable plant varieties and cultivate markets for their products Fortunately, farmers don't have to wait to begin the process of land use change "The good news from this report is that we've got a few things we can run with, now," says Dr Williams "And we've got a host of promising options we can test out for the future." "The take-home message is: the techniques we have for fighting salinity are inadequate, but some encouraging land use options are emerging that warrant research, development and large scale testing." • For a copy of this report contact CSIRO Land & Water CONTACT: ■ Richard Stirzaker, CSIRO Land and Water Ph: (02) 6246 5570 ■ Leanne Dempsey, Ph: (02) 6246 5717; The unacceptable alternative: saline area at Tharbogang (near Griffith) NSW 20 e-mail: leanne.dempsey@cbr.clw.csiro.au ■ Marg Bryant, Ph: (08) 9333 6215; e-mail: margaret.bryant@per.clw.csiro.au S A L T Home M A G A Z I N E Future landscapes: take your pick Current options and future prospects for managing dryland salinity: Annual cropping This is the preferred economic option, but it is ineffective in attaining leakage targets except in a small proportion of the Murray-Darling Basin There is little opportunity to reduce the leakage by the magnitude required beneath the root zone However phase farming, companion farming and agroforestry practices that reduce leakage are in harmony with the organic philosophy and are therefore more likely to be adopted High rainfall tree products These products are effective in reducing leakage, and profitable, but their proven potential is currently limited to a small proportion of the Basin Saltland farming: sheep grazing on a saltbush and grass pasture near Deniliquin, NSW Rotations of winter and summer crops that are sensitive to water conditions of soil make a useful contribution in those parts of the Basin with significant Low rainfall tree products summer rainfall Opportunity cropping is a relatively While this is potentially the most effective land-use mature area in research agronomy An applied research option for managing salinity by reducing leakage, it is effort over the next five to 10 years on suitable not commercially viable due to a lack of markets to drive crop/soil/rainfall combinations could yield improved reforestation and/or re-vegetation at the necessary scale systems in terms of salinity control and profitability A very significant, well-focused research effort over the next 30 years will be essential to develop: new markets; tree crops to produce fruits, nuts, oils, pharmaceuticals; Phase farming bush foods; and forestry products including specialty This is effective when the lucerne phase is long enough timbers, charcoal, carbon credits and to dry the subsoil and the cropping bio-mass energy applications phase is terminated before leakage recommences Reductions in Agroforestry leakage of between 50 per cent Agroforestry can be more profitable and 70 pc are associated with than tree crops alone, but its reduced profitability This is a effectiveness depends on the proportion mature area of agronomic research planted to trees, and on the skill of and systems are well advanced and locating trees in the right parts of the available Research over the next landscape Further research is needed to five years should overcome determine which tree/crop/pasture dependence on lucerne and finemixtures can reduce leakage to tune the application of phase acceptable levels and continue to give farming to improve profitability and economic return It will build on and drainage outcomes benefit from work essential to the development of commercial tree crops Companion farming and new agricultural plants Over-sowing annual cereals into perennial forages/pastures holds Perennial pastures promise of significantly reducing Perennial pastures leak less water leakage beneath the root zone beneath the root zone than annuals, but Research is needed over at least 5higher rainfall, winter dominance, acid 10 years on species and agronomic and shallow soils, and grazing pressure practice to provide viable systems all compromise their potential across the southern half of the Basin Research and New agricultural plants development should focus on Some potential exists to select or ameliorating subsoil and on deeper Opportunity cropping: wheat crop breed long season, perennial rooting species growing where rice grew previously and/or deep-rooted cultivars of in the Murrumbidgee Irrigation current crop and fodder plants that Saltland farming Area, near Griffith, NSW may substantially reduce deep Saltland farming allows for soil Opportunity cropping drainage, and to fit these plants into new farming systems This will require a substantial and well-focused research effort over the next five to 25 years Organic farming While the demand for organic produce is growing in the marketplace, organic farming is not necessarily any more effective than annual cropping in controlling leakage stabilisation and provision of stock feed but makes little long-term contribution to managing the watertable, reducing salt loads to rivers and therefore to water quality Identifying species and management practices that make best use of such land is important because of the huge areas that will be affected by salt, but the impact of this research on controlling land and river salinisation will be relatively small T h e M a g a z i n e o f A u s t r a l i a ’s N a t i o n a l D r y l a n d S a l i n i t y P ro g r a m salt 21 Home Airborne geophysics: why and where? A irborne geophysics is being billed by some as a 'magic bullet' for salinity - new technology that may become an important tool for many land managers But what exactly is it and how useful is it likely to be? Jo Curkpatrick fills in the background and notes some words of caution from Western Australian experience In April 2001 the Commonwealth-funded Airborne Geophysics Survey, marketed as the 'Ultra Sound of the Earth', will begin in two selected catchments in Western Australia, later extending to other States This is part of the National Action Plan on Salinity and Water Quality Airborne geophysics for agriculture is a recent spin-off from the mineral exploration industry and features three main components - magnetics, radiometrics and electromagnetics Magnetics measures variations in the earth's magnetic field and can provide a picture of the geology of an area Radiometrics, which measures the products of radioactive decay of naturally occurring minerals in the surface soil, can be used to help delineate soil types Electromagnetics essentially measures the 22 electrical conductivity of layers of soil and weathered rock Of the three, electromagnetics (EM) appears most directly valuable for salinity because of its potential to measure salt store beneath the surface and locate underground streams, known as palaeochannels The technology involves a wire cable connected to the outside of an aircraft (aeroplane or helicopter) which 'pulses' an electric field into the ground below This induces a secondary current in the ground and the strength of this current - and the time it takes to decay - are monitored by a sensor behind the plane Interpretation of these signals enables depth and conductivity of saline areas to be measured Because of the height of the aeroplane and a line spacing of 200 to 400 metres the resolution of mapping is relatively low compared with that from ground based EM systems, such as those carried on motorbikes - a survey unit familiar to many landholders The data require skilful interpretation in conjunction with other information such as soil and landform maps, groundwater monitoring and aerial photographs In February more than 200 people debated the technologies at a national conference in Bendigo, Victoria In one paper, Dr Richard George from Agriculture Western Australia outlined findings of a cost-benefit analysis of airborne geophysics for a catchment in the WA wheatbelt "We undertook an analysis for NDSP in which we compared the values of existing sets of data and that added by geophysics," he said "Encouragingly, after all the costs were taken into account there was a potential net benefit However most of the benefit was driven by information from radiometrics (soils)." Dr George identified, as a general rule, three criteria need to be satisfied before airborne geophysics is cost beneficial: • a likely net positive cash flow from the agricultural activity in the catchment; • a relatively low level of knowledge of the catchment; • good potential for other off-farm benefits, such as maintenance of infrastructure, developing and maintaining groundwater resources, protection of significant biodiversity areas or managing water quality "The use of geophysics needs to be matched carefully to an application It has to be driv- S A L T Home Key points ■ Major catchment surveys to detect salinity using airborne geophysics will begin in April ■ Cost-benefit analysis of the technology suggests geophysics needs to be carefully matched with an application ■ Airborne geophysical data, used in conjunction with other relevant data, can provide unparalleled insights into catchment evolution and hydro-geological processes ■ However, an understanding of these processes is essential for managing dryland salinity in agricultural catchments en by a real need and it requires considerable investment in developing scientific and community capacity "There is little point in a product that just describes the problem more accurately, no matter how appealing It must be able to deliver cost-effective decisions." In another presentation, Russell Speed from Agriculture Western Australia at Geraldton reminded delegates that airborne geophysics was a tool to facilitate the understanding of catchment (hydrology) processes "Airborne geophysical data, used in conjunction with other relevant data, can provide unparalleled insights into catchment evolution and hydro-geological processes An understanding of these processes is essential for managing dryland salinity in agricultural catchments," he said Russell had first-hand experience with two surveys at Carnamah and Chapman Valley Carnamah, flown in 1992, aimed to investigate what contribution airborne geophysics could make to improve catchment management with an emphasis on salinity Prior to the survey little was known about the hydrology apart from the obvious vast expanses of salinity The airborne geophysics provided the basis for developing a very detailed understanding of the catchment hydrology, but gave little insight into how to manage salinity "The limitation is not the airborne geophysics, rather the agronomic or cost-effective engineering solutions to 'fix' existing salinity," Russell commented "Groundwater quality typically ranges from two-thirds of the salinity of seawater to one and half times seawater and the options simply don't exist! "Seven-and-a-half years later we continue to monitor groundwater in the catchment Watertables rise and fall in response to seasonal rainfall, but there don't appear to be any long-term trends This suggests the catchment has reached a post-clearing equilibrium and the salt-affected areas are probably not spreading "So if it is not spreading, there is no need to intervene and little application for geophysical data for salinity management." By contrast, the Chapman Valley (WA) airborne geophysical data in 1997 did in fact contribute to management In this area, there was a good understanding of the processes controlling groundwater accumulation, discharge and salinity With airborne geophysics it was possible to map the bedrock and regolith (weathered and sedimentary material over the bedrock) "The data clearly delineated known wet areas and seeps at a sub-paddock level that could be treated productively with suitable perennial pastures," Russell said "A 20-metre deep palaeo-channel was also identified containing a potable water resource that might be used in the future If it is not to be developed in the near future, it should be protected from contamination from agricultural chemicals 'Management within a catchment depends on understanding the hydrology and appreciating the environmental limitations, not just the geophysics," he added CONTACT: ■ Dr Richard George, Agriculture Western Australia Ph: (08) 9780 6100, E-mail: rgeorge@agric.wa.gov.au Airborne geophysics technology (opposite and left) is increasingly being adopted as a tool for assessing dryland salinity risk across catchments M A G A Z I N E Tell your story in SALT Australia's National Dryland Salinity Program (NDSP) is a partnership in research, development and extension tackling the salinity risk to Australia's land and water resources Every success story in the battle against salinity should be told - your experiences and solutions might help others Do you have a story to tell about your experiences in tackling salinity? If so, SALT magazine wants to help you share it Contact one of the NDSP Communication Co-ordinators listed below: National Kim Mitchell, Currie Communications Ph: (03) 9696 5899 Fax: (03) 9696 6285 E-mail: kim@curriecom.com.au Queensland Mark Warnick, Department of Natural Resources and Mines Ph: (07) 3362 9318 Fax: (07) 3896 9625 E-mail warnickmf@dnr.qld.gov.au New South Wales Lisa Gray, Department of Land and Water Conservation Ph: (02) 9228 6111 Fax: (02) 9228 6464 E-mail: lgray@dlwc.nsw.gov.au Victoria Jo Curkpatrick and Diana Wolfe, Span Communication Ph: (03) 9328 5301 Fax: (03) 9328 5302 E-mail: jocurk@enternet.com.au South Australia Bruce Munday, Clear Connections Ph: (08) 8538 7075 Fax: (08) 8538 7075 E-mail: bcmunday@senet.com.au Western Australia Georgina Wilson, Agriculture Western Australia Ph: (08) 9368 3889 Fax: (08) 9474 2018 E-mail: gwilson@agric.wa.gov.au For further information about Australia's National Dryland Salinity Program, visit our web-site at the following address: www.ndsp.gov.au T h e M a g a z i n e o f A u s t r a l i a ’s N a t i o n a l D r y l a n d S a l i n i t y P ro g r a m salt 23 Home salt The Magazine of Australia’s National Dryland Salinity Program "My experience sends the message that all Australian landholders, no matter what your location, should be awake to the signs of salinity, high water tables and subsequent management that is required" Murray Brimblecombe, livestock and grain farmer, QLD (see story page 18) "Lucerne is obviously a key to productivity on this farm but revegetation is also very high on our agenda the network of trees and shrubs now support birds we didn't even know existed, along with all the other elements of biodiversity which make this a more sustainable farm" Philip and Diane Down, dairy farmers, SA (see story page 4) SALT Magazine brings you success stories from people tackling dryland salinity on their land or in their area Dryland salinity remains a major threat to the long-term sustainability and profitability of Australian agriculture and is increasingly impacting on infrastructure in urban and regional areas However, success in managing salinity is being achieved across Australia, through a variety of means Australia's National Dryland Salinity Program (NDSP) is a partnership in research, development and extension tackling the salinity risk to Australia's land and water resources NDSP regularly publishes SALT Magazine to tell personal stories of success in managing dryland salinity in a straightforward style SUBSCRIBE TO SALT MAGAZINE If you would like to receive a free copy of SALT Magazine, or wish to amend details of your subscription or nominate a friend or neighbour who does not yet receive the publication, please fill in the below subscription coupon and send to: Reply Paid 80986 The Editor, SALT Magazine c/-GPO Box 2182, CANBERRA ACT 2601 or fax to: (02) 6257 3420 For further information about Australia's National Dryland Salinity Program, contact one of our Communication Co-ordinators (see page 23) or visit the NDSP website at www.ndsp.gov.au Subscription: ❑ Please make me a free subscriber to SALT ❑ Please not send me SALT Mr/Mrs/Ms First name Surname Position Company/ property name Address Suburb/ town Phone Email State Fax Postcode