Comments on the Western Australian Salinity Action Plan
Submission on the Western Australian Salinity Action Plan
David J Pannell, Agricultural and Resource Economics, University of Western Australia
These comments relate to the original version of the Salinity Action Plan. They focus on the single most important improvement which needs to be made to the plan.
Some fundamental premises:
If these premises are accepted, then we are completely reliant on farmers deciding that they are willing to invest in large-scale revegetation. There are three possible broad strategies by which we might hope to make farmers willing to make this investment.
The fact that we are reliant on farmers’ decisions has very important implications for the Salinity Action Plan. The level of revegetation that comes into existence will be that which results from farmers’ reactions to the farming options, the government policies and institutions in place. In other words, to be willing to revegetate, farmers must be able to perceive for themselves that the benefits of revegetation will outweigh the costs.
It is important to recognise and accept that we will not succeed in achieving high levels of adoption of woody perennials if their adoption is highly unprofitable to farmers. We should not expect acts of great self-sacrifice in the interests of the environment and the public good, except from an exceptional few farmers. We might wish for it, but it would be foolhardy to rely on it. We cannot afford to be so optimistic.
In order for it to be economically worthwhile for farmers to adopt woody perennials on the necessary scale, it is clear from modelling studies that they will have to generate a direct economic return in addition to their impact on the salinity problem.
Strategies 2 and 3 are together very powerful tools for promoting adoption of new farming innovations in situations where the available options are in fact of benefit to the farmers but are relatively unknown to them. However, there are currently large areas of the agricultural region for which there is no woody perennial available which generates a significant direct financial return. In these areas, strategies 2 and 3 will NOT be effective. The only hope for such areas, given the premises I started with, is strategy 1. Only after that has been successful in creating profitable new options can strategies 2 and 3 be successful in promoting adoption.
I believe that this is an absolutely fundamental point which has not been adequately recognised in the existing Salinity Action Plan. The plan includes 28 "actions", but only one of these actions which corresponds to my strategy 1: action number 4.6. There is too much reliance on communication, extension, social pressure, sharing information, etc. (i.e. strategy 3) given the non-availability of suitable options which are readily and voluntarily adoptable by farmers.
The investment in action 4.6 is clearly too small, given its pivotal role if we are to succeed in coping with salinity in this state. If additional funds cannot be secured to increase activity in this area, it would be justified to reallocate funding away from other areas and into this one.
The inadequate funding of action 4.6 means that its current focus is too narrow and conservative. This is exemplified by the narrow focus on oil mallees within the lower rainfall regions, where the salinity risk is greatest. I believe that it is very worthwhile developing an oil mallee industry, but the nature of agriculture is that even if oil mallees are highly successful, they will only be suitable for certain niches within the farming system. We need a wider range of options to cover a wider range of niches. There should be attempts to identify these options by screening and evaluating the widest possible range of species, both native and non-native.
If we are successful in generating options which are sufficiently profitable, then they will "sell themselves", and the extension problem, while still formidable, will be greatly diminished (as with blue gums on the south coast).
More likely is that the options generated will be marginal or slightly unprofitable from a short-to-medium-run profit point of view, and their impact on salinity will be critical in the equation facing farmers considering their adoption. In this situation, we will need to rely on a strong extension program, and social factors will be critical in achieving adoption.
I am not arguing that R&D will lead automatically to a solution. Investing in this type of R&D involves a risk of failure. However it is my belief that if this type of R&D is not conducted, then we will definitely fail to avert the coming economic and ecological disaster, whereas a large investment in development of new tree-based options at least gives us a possibility of success.
There are other issues in the plan which could be improved, but this is the most important by a very large margin.
Why marketing won’t help if you’ve got nothing to sell:
A response to the Salinity action plan
Ted Lefroy, Centre for Legumes in Mediterranean Agriculture, University of Western Australia, Nedlands 6097
Summary
The revegetation targets in the Salinity Action Plan are grossly inadequate, relying on a small proportion of the landscape devoted to woody perennials and an unjustified expectation of large areas of lucerne. On the basis of research into the factors governing water use of native plant communities in southern Australia, it is suggested that a far higher proportion of the agricultural landscape will need to be planted deep rooted (woody) perennials than is acknowledged if the stated aim of dramatically reducing the impact of salinity is to be achieved.
The expectation that lucerne will expand into lower rainfall areas to augment the water use role of woody perennials is not matched by evidence that existing varieties are suited or that specific effort is being put into developing well adapted varieties of lucerne or any other herbaceous perennials.
There are no solutions for managing salinity that are both biophysically and economically viable for the under 600 mm annual rainfall zone, two thirds of the cleared land in the agricultural area.
The emphasis of the plan on extension of the few inadequate existing options rather than the development of options that are both biophysically and economically viable at a scale necessary to have an impact is not justifiable in the light of the above.
Why will a large proportion of the landscape require revegetation?
The nature of the climate and soils of this region dictate that if water is to be biologically managed, it requires plants that are:
It has often been assumed, more on the basis of wishful thinking than plant physiology or ecology, that current rates of recharge can be managed by planting a conveniently small proportion of the landscape to ‘high water use’ vegetation. This would only be possible where there is a sufficient area of land in a particular catchment with shallow, fresh water tables for the transpiration of perennial plants to match total recharge in that catchment. Under the altered hydrologic regime there are of course parts of the landscape where trees have better access to water now than they did prior to clearing. The problem with relying on trees over water tables to do the job is that:
Where there is no access to a water table, studies of native vegetation suggest that the leaf area and hence the water use of a plant community will reach equilibrium with rainfall as that community matures. That is, they will use what falls on them. As the effective capture zone of most trees only extends a few metres beyond its canopy, large proportions of the landscape will need to be occupied by trees or herbaceous deep rooted perennials where shallow water tables are absent or too saline.
Why the emphasis on woody plants?
Candidate species must be capable of extending roots to depths in excess of 10 metres in many soils to access sufficient water to maintain summer growth and need to be tolerant of low fertility and, over much of the landscape, sub soil acidity. It is very difficult to find herbaceous plants that have these characteristics, as evidenced by the paucity of summer active herbaceous perennials in the flora of the region. Lucerne is the nearest contender but is only likely to be suited to several hundred thousand of the 15 million hectares of cleared land in the medium to low rainfall areas due to soil acidity. No other candidate herbaceous perennials exist at present and there is no significant effort underway to systematically identify them.
Tinkering at the margin will not be enough
For these reasons, if salinity is ever to be managed in south western Australia, the revegetation challenge is likely to involve a larger area of deep rooted woody perennial plants than farmers can afford to retire from agricultural production or establish at their own cost and larger than state or federal governments are willing or able to fund. This means a significant change to the nature of the agricultural landscape and hence the nature of agriculture. A revegetation challenge of this scale is only likely to be met if it is commercially driven. In the > 600 mm rainfall zone this is already happening with commercial forestry. In the < 600 mm rainfall zone, this will not happen without an R & D effort to systematically identify and develop commercial species. Even then, it is not certain that the slow growth rates and low biomass production characteristic of trees in medium to low rainfall areas will be sufficient to sustain commercial use. Also uncertain is the compatibility of commercial harvesting and water management, as removal of biomass is likley to compromise water use.
Moral obligation
If this revegetation on this scale is not carried out, salinity will run its course, affecting a projected 30% of the 20 million hectares of cleared land before a new equilibrium is reached between discharge and recharge. In that event, it will not simply be a case of business as usual on the remaining 70% of arable land and a socially acceptable level of salinity. First there are effects at a distance other than salinity such as eutrophication, ground water pollution, soil erosion and soil acidity that are also consequences of a perturbed hydrologic regime, involving far more than hectares of bare salt. Second there is the leveling off and eventual decline in productivity resulting from the loss of productive land that, while absorbed at the farm scale through amalgamation, will bring many local government authorities to their knees as their income base is eroded. Third and most significantly, there is the moral responsibility to either repair the damage done or cease any pretense of commitment to the concepts of sustainability and inter-generational equity contained in the National Strategy for Ecologically Sustainable Development endorsed by state and federal governments.
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