What is the method to overcome the salinity?

Answer 1

Preventing and managing salinity

When dealing with salinity it is important to keep in mind that many assets (natural or built) have varying levels of tolerance to increases in salinity. Therefore the value and the context of the asset at risk must be considered.

We use 2 main terms when assessing whether salinity may be a problem:

• salinity hazard-the inherent characteristics of the landscape that predispose it to land and water salinity
• salinity risk-the probability that land or water salinity may develop if certain management practices or land-use changes occur.

Assessing salinity risk

The Salinity Risk Assessment Framework (Grundy et al. 20071) is the preferred method to assess salinity risk in Queensland. It uses multiple lines of evidence to assess whether salinity will occur and what impact it could have on an asset.

The 4 components of the risk assessment are:

• biophysical hazards-the inherent features of a landscape that may contribute to salinity processes
• management influences-the level of risk due to land management practices
• salinity stage-the progression of salinity processes in the landscape and the amount of time before salinity may impact on an asset
• assets-the value of the asset under threat.

Salinity risk assessments have been undertaken in 4 catchments across Queensland:

• Strategic Salinity Risk Assessment in the Condamine Catchment
• Salinity Risk Assessment for the Fitzroy Basin
• Salinity Risk Assessment for the Queensland Murray-Darling Region
• Burdekin Dryland Salinity Project (undertaken by NQ Dry Tropics).

The first 3 documents referred to above are available from the library catalogue.

Methods of prevention

In high-risk areas:

• monitor groundwater levels and the amount of salt in the land and water
• encourage preventative actions to stop salt moving towards the surface
• stop further loss of deep-rooted native vegetation in high-risk areas as well as areas that contribute groundwater to them.

In at-risk areas:

• retain and regenerate native vegetation
• avoid building dams at sites where the water table is high
• locate roads along ridges where disruption to water tables will be minimal
• site houses (and septic systems) away from areas with high water tables
• maintain good pasture cover through conservative stocking rates
• adopt cropping practices that minimise deep drainage.