Salinity control credits

Cause: Deep-rooted perennial native vegetation has been substantially removed over the last 150 years. The shallow-rooted annual crops and pastures that have been introduced in its place typically have a much lower capacity to capture and transpire water. This has allowed significantly more water to pass through the soil to the water table, mobilising salt from groundwater aquifers and bringing it to the soil surface, where it also seeps into streams and rivers.

Effects: The actual and predicted impacts of salinisation on natural and human systems are severe: damage to aquatic and terrestrial ecosystems and loss of biodiversity; extensive degradation and loss of productive land; reduced yields from irrigated crops and pastures; salt-affected water supplies; and considerable damage to infrastructure such as roads.

Towards a solution: Broad-scale change in the way we manage land and water resources is needed. In order to reduce or eliminate the process of groundwater rise, extensive and strategic replanting of perennial vegetation is fundamental. Depending on the catchment situation, this may in-volve revegetation of over 50% of the landscape.

The relationship between the cause, effects and the proposed solutions to the problem of dryland salinity is complex.

Cause and effect are separated by place and time. Generally, the salinity impacts of land clearing in the uplands of a catchment are felt mainly in lowlands and further downstream. Revegetation to con-trol salinity must therefore often take place in areas geographically removed from the sites of greatest impact. However, when those responsible for producing a decline in ecosystem services are not directly affected by the impacts, there are no established economic forces to encourage investment in ecosystem restoration.

There is also a considerable time lag in the emergence of problems and the operation of solutions. Even with immediate commitment to implement land-use changes, the effects of past practices will continue to influence decision making for decades.

Within the current policy framework, proposed solutions to dryland salinity largely depend on landholders voluntarily changing over from a system based on annual plant species towards a greater use of perennial and deep-rooted plants. Yet for the landholders affected, the costs involved can be prohibitive. Land taken out of production may amount to significant loss of income and the availability of economically viable replacements is uncertain.

In an attempt to surmount these barriers, a pilot scheme of "salinity control credits" has been pioneered by State Forests NSW and Macquarie River Food and Fibre (an industry organisation representing the majority of irrigators in the Macquarie catchment). This scheme effectively places a value on the ecosystem services provided by native vegetation in the upper catchment of the Macquarie River, and encourages investment and cost sharing for the restoration and enhancement of these services.

State Forests have entered into an agreement with various landholders in the upper reaches of the Macquarie to plant and manage native forest on their land. The landholders are paid an annual annuity. The services provided by this vegetation have been characterised as "salinity control credits", defined according to the quantity of water removed by transpiration and, by implication, the reduction in water contributing to groundwater rise in the lower catchment. State Forests has sold the rights to these credits to Macquarie River Food and Fibre, whose members will be adversely affected by the increasing salt load within the catchment, and therefore stand to benefit from revegetation of the upper catchment. Title to the timber resource and the carbon stored therein is retained by State Forests.

The proponents of the Macquarie pilot hope to use this scheme to refine the measurement of transpiration rates – and its correlation with downstream salinity reduction benefits – and promote the development of a broader salinity trade. The NSW Government is currently involved in the preparation of a Salinity Management Strategy, which will set desirable salt-load targets for individual catchments. These targets may provide the framework for future salinity trading on a catchment basis.

The Macquarie scheme is part of a growing trend towards market-based solutions for natural resource problems, which is being led substantially by State Forests NSW. While there are potential benefits to be gained through the development of appropriate cost-sharing mechanisms and the stimulation of investment in the required land-use change, it is imperative that environment groups engage with this trend and closely monitor its application. The Macquarie scheme raises a number of specific concerns.

The design of appropriate responses involves complex considerations of scale and placement of revegetation within a catchment. The identification of key areas for revegetation is a fundamental precursor to an effective trading scheme. The detailed analysis required has not yet been conducted for most catchments.

The salt load targets for a catchment must adequately constrain further development of practices which contribute to salinity; any trading scheme should be designed within these limits. At present the Macquarie scheme is conceptually different to that of carbon credits: investors are purchasing credits to prevent worsening of salinity pollution in the long term and to promote restoration, rather than using credits to offset the continued production of pollution. This distinction should be maintained. Offsetting further development of salt-producing land uses should be discouraged.

In the Macquarie River Pilot, the rights to the vegetation planted as a salinity response include a future right to harvest the timber. In many cases it will be difficult to reconcile this right with the purposes of vegetation establishment (salinity control). Vegetation that attracts a salinity credit should not necessarily also carry a right to future harvest. A salinity trading scheme would be enhanced by binding agreement to maintain the provision of benefits in the long term.

Finally, account must be taken of the environmental impacts of extensive establishment of plantations within the landscape. Plantations can have severe and negative impacts on water and soil quality (and biodiversity), especially if managed on short-term rotation for timber production, and if exotic species and monoculture predominate. Planting as a response to salinity should ideally aim to simultaneously achieve broader environmental benefits. Where possible a variety of local native species should be used. Existing native vegetation should not be cleared to introduce ‘productive’ forests for harvest and carbon or salinity trading.

Anita Sundstrom is the Western Project Officer for the NPA/WWF Western NSW Conservation Project.

NSW Salinity Summit

The NSW Government held its Salinity Summit at Dubbo in March. The Summit brought together over 200 people including indigenous people, farmers, natural and social scientists, environmentalists, urban residents, and State and local government representatives. The Summit was co-chaired by the Right Hon Ian Sinclair and the Hon David Simmons. No less than eight State Government Ministers attended. The Premier, Bob Carr, opened the Summit and undertook, on behalf of the Government, to work with the community to combat salinity in New South Wales.

The summit communiqué records that ‘the Summit recognised the issue of salinity as one of the most difficult and important issues confronting New South Wales and Australia, challenging our productive agricultural enterprises, our valuable infrastructure and our fragile environment, as well as affecting public buildings and homes in suburban Sydney and many country towns.’

The Summit agreed that there was no single solution and that a long-term approach was required. There was agreement that a coordinated strategy involving government, industry and the community needed to be developed urgently and pursued vigorously.

Key recommendations included:

• development by the NSW Government of an integrated Salinity Strategy encompassing solutions aimed at maintaining agricultural productivity, conserving biodiversity and protecting the built environment

• the NSW Government should investigate ways to provide better-coordinated natural resource management

• environmental planning instruments should incorporate salt targets which reflect what people want from their landscapes.

Roger Lembit, NPA President