Land-use change is the key to protecting biodiversity in salinising landscapes

Abstract

This paper argues that the loss of biodiversity in salinising landscapes will be reversed only by addressing the source of the problem: farming systems that leak into the water table. Existing farming systems based on annual crops and pastures will need to be replaced by farming systems that have a significant element of perenniality. The literature suggests that 50–80% of the agricultural landscape needs to include perennial plants.

The options are perennial pasture plants or trees, the latter for bioenergy, wood products and fuel. Because of the complexities of introducing new industries, the greatest short-term impact will be achieved by using perennial pastures for existing livestock industries. However, the need to introduce trees and shrubs is such that governments and entrepreneurs should be encouraged to see that new industries are an imperative in rural Australia. To achieve this we need substantial private and public investment, both on and off farms.

Techniques are available to value biodiversity and these should be used to fortify the moral and philosophical arguments commonly used to protect biodiversity. It is suggested that a financial value placed on biodiversity, however inadequate, may, in time, be persuasive to governments. Contingent valuing and other non-market methods should be developed and, most importantly, used to bolster the moral and philosophical arguments if governments and the community are to respond to the perceived crisis in biodiversity management.

The paper warns of possible tradeoffs between water quality and runoff. We have become dependent on high levels of runoff, and reductions are likely to cause problems both in terms of environmental flows and for the irrigation industries. Yet many of our solutions to dryland salinity will reduce runoff. Location will be all important in the development of perennial-based farming systems, avoiding, where possible, the areas of greatest runoff. Therefore, there are no blanket solutions. Policy will need to distinguish areas with high payoffs or low costs of abatement.

Finally, the paper outlines some of the initiatives that are open to government and industry to reverse the trend towards dryland salinity. Emphasis is given to the provision of incentives and the removal of disincentives.