A RECENT GRDC-supported risk assessment for dryland salinity in Queensland shows that, despite popular perceptions, salinity is an emerging issue in the north. While the soil profiles and time frames may vary from the southern and western phenomena, underlying causes are similar, including .the replacement of perennial native vegetation with shallow-rooted annual crops.
This makes it a good time to revisit the national picture on groundwater and salinity and the grains industry's Contributions to developing profitable solutions.
For graingrowers these are urgent issues. About 2.5 million ha of land are affected to greater or lesser degrees by salinity, causing production losses estimated at about $130 million a year - and more are threatened.
Additionally, there are the related off-farm impacts, such as the increasing salt loads carried by major rivers in agricultural regions that also threaten the future of irrigation industries.
A major focus, backed by GRDC research investments, is to develop farming systems that use more 6f the available soil moisture. That often means reintroducing perennials as well as using other strategies like opportunity cropping to use up available soil moisture before it drains and flows through the deeper soil profile to mobilise salts.
The GRDC supports the breeding of annual crops, which can better take up annual rainfall. That includes also pursuing 'blue sky' biotechnology solutions - yielding crops that are more water-use efficient -a boon for opportunity cropping systems.
Getting the agronomy right is equally important - healthy crops use more water, leading to a win-win situation with more yield and profit as well as an environmental benefit.
Once established, salinity is hard and time-consuming to reverse. This means that in some cases versions of salt-land agronomy will be the solution, growing pastures and crop species that are adapted to higher levels of salt. (See also p20 of this issue for some truly lateral thinking possibilities suggested by CSIRO.)
In other cases, farm forestry, or returning or retaining parts of the land as native vegetation, will be a long-term profitable strategy. Profit with a long-term view of a healthy resource base forthis and future generations.
Like so many emerging issues in agriculture, the 'three Ps' are coming into play - concerns with on fartn 'Profit' will need to be tempered by action on behalf of the 'Planet', because 'People' are pressing governments to be more active on their behalf.
North, South, West