Investigations helping concerns over dry saline land impacts
Over the past 18 months, the Murraylands and Riverland Landscape Board, together with Insight Extension for Agriculture’s (AIR) Chris McDonough and the Department of Primary Industries and Regions SA’s Brian Hughes have been investigating the rising issue of dry saline land throughout the Northern Mallee and Murray Plains regions locally and also areas on the Eyre Peninsula.
Posted 24 August 2021.
This project is supported by the Murraylands and Riverland Landscape Board through funding from the Australian Government’s National Landcare Program and the landscape levies.
Concerns over the growing impacts of dry saline land degradation across the Murray Mallee and the Eyre Peninsula have increased in recent years.
A survey commissioned by the Murraylands and Riverland Landscape Board and AIR Eyre Peninsula was conducted between December 2020 and January 2021 and distributed to farmers through various networks for online completion. One hundred surveys were completed, including 43 from the Murraylands region.
Dry saline land or “magnesia patches” describe areas in paddocks that have become saline in the surface layer and toxic to plant growth. This results in bare, unproductive patches of ground. They are not driven by the underlying effects of groundwater, stream flows or perched water tables. The impacts can be highly detrimental to farming practices across a range of landscapes.
Following the survey, soil testing was carried out at many properties over various sites and landscapes, measuring pH and salinity at multiple depths to gauge the characteristics of the salt within the soil profile.
Two farmer case studies were developed with more detail about the individuals farming systems, agronomics, livestock, grazing and what treatments and or applications the farmer has used on the issue.
This investigation showed that dry saline land affects a wide range of soil conditions and appears in vastly different landscape environments. Patches become highly saline in areas that have moderate to high levels of transient subsoil salinity. They are also highly conducive to capillary rise of moisture and evaporation, leaving the salts behind on the surface. This is exacerbated by environmental and land management conditions such as long hot summers, periods of drought and the loss of surface plant growth and/or vegetative cover.
The next phase of this project will be looking into treatments and management methods to rejuvenate the dry saline patches in much more detail.
If you think you may have dry saline patches on your property, please phone Denham Ewans, Sustainable Agriculture Officer on 0419 093 665.