Dr Richard George is the 2000 winner of Australia's most prestigious accolade for innovation in salinity research and development - the National Dryland Salinity Program's WE Wood Award. This precis is an extract from the 2000 WE Wood Memorial Lecture, presented by Dr George in Perth in late 2000.

Salinity reclamation or management - feasibility versus attractiveness

There is no doubt that salinity is a massive force altering the face of Australia's natural, social and cultural resources. The question as to whether salinity reclamation or management is possible is a question of the debate between feasibility of options working versus the attractiveness of those options.

In late 1993, while having a beer in the Hines Hill pub, I asked a mate who was then the only experienced country-based hydrologist in WA, whether he thought salinity would look any better in 20 years. It's now only two years to go and the answer hasn't changed: No! So what has happened and what options do we have?

Projects such as the National Land and Water Resources Audit will soon publish a comprehensive 'regionally-based' review of salinity within Australia, which collates over a decade's data and experience in salinity extent, processes and management. Reports such as this document predict a massive increase in the area of salinity (land and water); describe these trends and impacts in a landscape context; and provide cases studies of the use of tools to describe changes to the landscape's hydrology and the role of management options.

Three levels of generic options are recognised: recharge, discharge and adaptation.

Modelling and measurements undertaken in the 1990s have shown that recharge management in southern Australia is less likely to deliver salinity outcomes than was initially postulated. Research indicates that trees will be required on vast areas to address recharge; that lucerne and its alternatives will also fall short of targets in many regions; and that managing annuals with agronomic systems (whether winter and summer active) while economically attractive, is not feasible and will make only small inroads into recharge control at levels that will impact on land and stream salinity.

While greater impacts will result in wetter and steeper landscapes where reduced recharge rates will be more effective at lowering watertables, even here impacts on streamflow and salt load may not reach attractive farm or regional targets.

As a result, discharge (engineering) options have recently attracted renewed interest, especially when used by farmers as a 'last resort' or by Government to save or protect natural or built infrastructure. In many areas, engineering systems will be unlikely to deliver salinity outcomes (reclamation) as either the landscape conditions are unsuitable (permeability, soil chemistry) or the costs are too great. Discharge options (e.g. open drains) must also await the rise of watertables and do not manage the 'recharge landscape' that will never become saline; their impact is typically confined to saline areas.

Some engineering systems, especially surface water management and some forms of groundwater drainage (leveed, or open drains), have been claimed to be more effective than was initially demonstrated in trials. In WA, the combination of lack of effectiveness of recharge options and significant current impact and potential salinity risk, has led to farmer-based 'operational experimentation', despite available evidence. Positive impacts claimed and demonstrated by farmers in some circumstances have led to a need to re-appraise the impacts of 'discharge based options' and to review the process of 'soil' salinisation.

Tentative evidence to date suggests that drains capitalise on variability in the soils, having a greater impact than was postulated; that drains more effectively manage waterlogging than has been appreciated; and that leaching of accumulated salts is significant and that crops may be able to tolerate annual salt accumulation from groundwaters, but not decades of 'stewing and evaporating' in scalds.

Finally, it appears likely that the downstream impact of well designed drains may not be as dramatic as first thought, when considered against the forces already set up in the landscape. For example, annual loads may be largely unchanged and vegetation may respond favourably to the certainty of the flow. However it is clear that different land managers and agencies do not share a similar view on likely impacts (scale and water quality issues become critical here).

The third system of management (adaptation) emphasises the uses and options for saline land and water. It is an area that is beginning to turn up choices that challenge our fundamental attraction to the goal of 'reclaim salinity at all cost' and in so-doing shrink what some now consider as vast and new 'soil and groundwater resource' developed since 1788. Saline areas are also mosaics of soils and salinity levels, and offer options for re-establishing some aspects of the biodiversity lost from the landscape. Finally, research into saltland options for new plants with high salt tolerance, algaes, saline aquaculture and potential desalination, mineral and energy development, continue to expand our horizons and challenge the view that salinity is unnatural and should be stopped wherever it is found.

Salinity management requires a fundamental rethink. We need to focus on a few critical issues and pursue them without the 'vegemite' approach salinity funding has seen to date.

First it's clear that if we decide to go for a landscape change, we need land uses that change the landscape, and the biophysical data and tools to design and forecast the impact of changes. Information and forecasting tools are critical to any salinity program. While an understanding of land and water processes will not deliver salinity management, a failure to recognise landscape attributes, accommodate them within options and reflect them in designs, will cause unnecessary failures. Landscapes work differently, respond differently and require collection and interpretation of biophysical data at paddock level to help derive and predict the impact of options.

Since 1993 and that beer in the Hines Hill pub, only one option looks at face value, capable of such a change: revegetation with commercial perennial species. While blue gums are not an option across most of Australia, they do indicate how quickly a change can occur when an alternative land use is more profitable that the alternatives. However the reality is that we have more than 100 million hectares of agricultural land, and this will discount the value of such wood-based options in the medium term. The possibility of energy and alternative products is appealing and should be pursued.

Second, we can choose to selectively manage our natural and built assets with a combination of engineering and revegetation. It will be hard to develop the process of selection, and to juggle local and national values; it should work; and while expensive, will be quick and provide experience that will be required in broadscale management.

Third, we should emphasis the conservation of the 70 to 80% of land that is not, or will never be saline - maintaining its productive potential, and using the 'new' perennials, water control systems and soil management options. (Interestingly, while many of these are now considered as recharge and salinity control measures, they are better viewed as a means to stabilise the slopes and valleys not affected.) We should buy time and where possible take some land from salinity.

Finally, we can choose to build new business opportunities from saline land, whether that be from the land, water or salt. In this way we can and should pursue both engineering and the so-called PUR$L options, together, not separately. Together the application and use of saline land and water is of greater benefit. For example, at one scale waterlogging control and establishing perennial shrubs will deliver productivity in spite of a shallow watertable; at the other extreme, leveed drains may allow cropping and the development of groundwater and salt-based industries.

It appears that for much of the flat and lower rainfall areas, reclamation with the current 'recharge based' options, while emotionally attractive, is not feasible in the short to medium term, although delaying onset and severity. Engineering options need to be re-evaluated against the alternatives and the impact of 'doing nothing', and systematic research into alternative business opportunities from saline land and water developed. Due recognition of the differences in treatment options need to be built around a knowledge of landscape processes and based on high resolution biophysical data, with confidence established using practical forecasting tools.

No change takes place, no matter how clever the science, without participation, profit and politics. In many ways these are tougher mountains to climb.